SyntaxFix

Programs & Examples On #Ace

The ADAPTIVE Communication Environment (ACE), a C++ network programming toolkit. For the ACE database available since MS Access 2007, use an ms-access tag and the ms-jet-ace tag. For the ACE editor, use the [tag:ace-editor] tag.

R : how to simply repeat a command?

It's not clear whether you're asking this because you are new to programming, but if that's the case then you should probably read this article on loops and indeed read some basic materials on programming.

If you already know about control structures and you want the R-specific implementation details then there are dozens of tutorials around, such as this one. The other answer uses replicate and colMeans, which is idiomatic when writing in R and probably blazing fast as well, which is important if you want 10,000 iterations.

However, one more general and (for beginners) straightforward way to approach problems of this sort would be to use a for loop.

> for (ii in 1:5) { + print(ii) + } [1] 1 [1] 2 [1] 3 [1] 4 [1] 5 >

So in your case, if you just wanted to print the mean of your Tandem object 5 times:

for (ii in 1:5) {     Tandem <- sample(OUT, size = 815, replace = TRUE, prob = NULL)     TandemMean <- mean(Tandem)     print(TandemMean) }

As mentioned above, replicate is a more natural way to deal with this specific problem using R. Either way, if you want to store the results - which is surely the case - you'll need to start thinking about data structures like vectors and lists. Once you store something you'll need to be able to access it to use it in future, so a little knowledge is vital.

set.seed(1234) OUT <- runif(100000, 1, 2) tandem <- list() for (ii in 1:10000) {     tandem[[ii]] <- mean(sample(OUT, size = 815, replace = TRUE, prob = NULL)) }  tandem[1] tandem[100] tandem[20:25]

...creates this output:

> set.seed(1234) > OUT <- runif(100000, 1, 2) > tandem <- list() > for (ii in 1:10000) { +     tandem[[ii]] <- mean(sample(OUT, size = 815, replace = TRUE, prob = NULL)) + } >  > tandem[1] [[1]] [1] 1.511923  > tandem[100] [[1]] [1] 1.496777  > tandem[20:25] [[1]] [1] 1.500669  [[2]] [1] 1.487552  [[3]] [1] 1.503409  [[4]] [1] 1.501362  [[5]] [1] 1.499728  [[6]] [1] 1.492798  >

I am receiving warning in Facebook Application using PHP SDK

You need to ensure that any code that modifies the HTTP headers is executed before the headers are sent. This includes statements like session_start(). The headers will be sent automatically when any HTML is output.

Your problem here is that you're sending the HTML ouput at the top of your page before you've executed any PHP at all.

Move the session_start() to the top of your document :

<?php    session_start(); ?> <html> <head> <title>PHP SDK</title> </head> <body> <?php require_once 'src/facebook.php';    // more PHP code here.

Using Lato fonts in my css (@font-face)

Well, you're missing the letter 'd' in url("~/fonts/Lato-Bol.ttf"); - but assuming that's not it, I would open up your page with developer tools in Chrome and make sure there's no errors loading any of the files (you would probably see an issue in the JavaScript console, or you can check the Network tab and see if anything is red).

(I don't see anything obviously wrong with the code you have posted above)

Other things to check: 1) Are you including your CSS file in your html above the lines where you are trying to use the font-family style? 2) What do you see in the CSS panel in the developer tools for that div? Is font-family: lato crossed out?

Embed ruby within URL : Middleman Blog

 
<%= link_to "http://www.facebook.com/sharer.php?u=" + article_url(article, :text => article.title), :class => "btn btn-primary" do %>   <i class="fa fa-facebook">     Facebook Share    </i> <%end%>

I am assuming that current_article_url is http://0.0.0.0:4567/link_to_title

Two constructors

Let's, just as example:

public class Test {     public Test() {         System.out.println("NO ARGS");     }      public Test(String s) {         this();         System.out.println("1 ARG");     }      public static void main(String args[])     {         Test t = new Test("s");     } }

It will print

>>> NO ARGS >>> 1 ARG

The correct way to call the constructor is by:

this();

Crop image to specified size and picture location

You would need to do something like this. I am typing this off the top of my head, so this may not be 100% correct.

CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB(); CGContextRef context = CGBitmapContextCreate(NULL, 640, 360, 8, 4 * width, colorSpace, kCGImageAlphaPremultipliedFirst); CGColorSpaceRelease(colorSpace);  CGContextDrawImage(context, CGRectMake(0,-160,640,360), cgImgFromAVCaptureSession);  CGImageRef image = CGBitmapContextCreateImage(context); UIImage* myCroppedImg = [UIImage imageWithCGImage:image]; CGContextRelease(context);

How to correctly write async method?

You are calling DoDownloadAsync() but you don't wait it. So your program going to the next line. But there is another problem, Async methods should return Task or Task<T>, if you return nothing and you want your method will be run asyncronously you should define your method like this:

private static async Task DoDownloadAsync()     {         WebClient w = new WebClient();          string txt = await w.DownloadStringTaskAsync("http://www.google.com/");         Debug.WriteLine(txt);     }

And in Main method you can't await for DoDownloadAsync, because you can't use await keyword in non-async function, and you can't make Main async. So consider this:

var result = DoDownloadAsync();  Debug.WriteLine("DoDownload done"); result.Wait();

Keep placeholder text in UITextField on input in IOS

Instead of using the placeholder text, you'll want to set the actual text property of the field to MM/YYYY, set the delegate of the text field and listen for this method:

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {     // update the text of the label }

Inside that method, you can figure out what the user has typed as they type, which will allow you to update the label accordingly.

python variable NameError

In addition to the missing quotes around 100Mb in the last else, you also want to quote the constants in your if-statements if tSizeAns == "1":, because raw_input returns a string, which in comparison with an integer will always return false.

However the missing quotes are not the reason for the particular error message, because it would result in an syntax error before execution. Please check your posted code. I cannot reproduce the error message.

Also if ... elif ... else in the way you use it is basically equivalent to a case or switch in other languages and is neither less readable nor much longer. It is fine to use here. One other way that might be a good idea to use if you just want to assign a value based on another value is a dictionary lookup:

tSize = {"1": "100Mb", "2": "200Mb"}[tSizeAns]

This however does only work as long as tSizeAns is guaranteed to be in the range of tSize. Otherwise you would have to either catch the KeyError exception or use a defaultdict:

lookup = {"1": "100Mb", "2": "200Mb"} try:     tSize = lookup[tSizeAns] except KeyError:     tSize = "100Mb"

or

from collections import defaultdict  [...]  lookup = defaultdict(lambda: "100Mb", {"1": "100Mb", "2": "200Mb"}) tSize = lookup[tSizeAns]

In your case I think these methods are not justified for two values. However you could use the dictionary to construct the initial output at the same time.

Why my regexp for hyphenated words doesn't work?

A couple of things:

  1. Your regexes need to be anchored by separators* or you'll match partial words, as is the case now
  2. You're not using the proper syntax for a non-capturing group. It's (?: not (:?

If you address the first problem, you won't need groups at all.

*That is, a blank or beginning/end of string.

Where do I put a single filter that filters methods in two controllers in Rails

Two ways.

i. You can put it in ApplicationController and add the filters in the controller

    class ApplicationController < ActionController::Base       def filter_method       end     end      class FirstController < ApplicationController       before_filter :filter_method     end      class SecondController < ApplicationController       before_filter :filter_method     end

But the problem here is that this method will be added to all the controllers since all of them extend from application controller

ii. Create a parent controller and define it there

 class ParentController < ApplicationController   def filter_method   end  end  class FirstController < ParentController   before_filter :filter_method end  class SecondController < ParentController   before_filter :filter_method end

I have named it as parent controller but you can come up with a name that fits your situation properly.

You can also define the filter method in a module and include it in the controllers where you need the filter

grep's at sign caught as whitespace

After some time with Google I asked on the ask ubuntu chat room.

A user there was king enough to help me find the solution I was looking for and i wanted to share so that any following suers running into this may find it:

grep -P "(^|\s)abc(\s|$)" gives the result I was looking for. -P is an experimental implementation of perl regexps.

grepping for abc and then using filters like grep -v '@abc' (this is far from perfect...) should also work, but my patch does something similar.

Accessing AppDelegate from framework?

If you're creating a framework the whole idea is to make it portable. Tying a framework to the app delegate defeats the purpose of building a framework. What is it you need the app delegate for?

When to create variables (memory management)

So notice variables are on the stack, the values they refer to are on the heap. So having variables is not too bad but yes they do create references to other entities. However in the simple case you describe it's not really any consequence. If it is never read again and within a contained scope, the compiler will probably strip it out before runtime. Even if it didn't the garbage collector will be able to safely remove it after the stack squashes. If you are running into issues where you have too many stack variables, it's usually because you have really deep stacks. The amount of stack space needed per thread is a better place to adjust than to make your code unreadable. The setting to null is also no longer needed

How to create a showdown.js markdown extension

In your last block you have a comma after 'lang', followed immediately with a function. This is not valid json.

EDIT

It appears that the readme was incorrect. I had to to pass an array with the string 'twitter'.

var converter = new Showdown.converter({extensions: ['twitter']}); converter.makeHtml('whatever @meandave2020'); // output "<p>whatever <a href="http://twitter.com/meandave2020">@meandave2020</a></p>"

I submitted a pull request to update this.

Please help me convert this script to a simple image slider

Problems only surface when I am I trying to give the first loaded content an active state

Does this mean that you want to add a class to the first button?

$('.o-links').click(function(e) {   // ... }).first().addClass('O_Nav_Current');

instead of using IDs for the slider's items and resetting html contents you can use classes and indexes:

CSS:

.image-area {     width: 100%;     height: auto;     display: none; }  .image-area:first-of-type {     display: block; }

JavaScript:

var $slides = $('.image-area'),     $btns = $('a.o-links');  $btns.on('click', function (e) {     var i = $btns.removeClass('O_Nav_Current').index(this);     $(this).addClass('O_Nav_Current');      $slides.filter(':visible').fadeOut(1000, function () {         $slides.eq(i).fadeIn(1000);     });      e.preventDefault();  }).first().addClass('O_Nav_Current');

http://jsfiddle.net/RmF57/

Autoresize View When SubViews are Added

Yes, it is because you are using auto layout. Setting the view frame and resizing mask will not work.

You should read Working with Auto Layout Programmatically and Visual Format Language.

You will need to get the current constraints, add the text field, adjust the contraints for the text field, then add the correct constraints on the text field.

Setting default checkbox value in Objective-C?

Documentation on UISwitch says:

[mySwitch setOn:NO];

In Interface Builder, select your switch and in the Attributes inspector you'll find State which can be set to on or off.

Highlight Anchor Links when user manually scrolls?

You can use Jquery's on method and listen for the scroll event.

Generic XSLT Search and Replace template

Here's one way in XSLT 2

<?xml version="1.0" encoding="UTF-8"?> <xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">   <xsl:template match="@*|node()">     <xsl:copy>       <xsl:apply-templates select="@*|node()"/>     </xsl:copy>   </xsl:template>   <xsl:template match="text()">     <xsl:value-of select="translate(.,'&quot;','''')"/>   </xsl:template> </xsl:stylesheet>

Doing it in XSLT1 is a little more problematic as it's hard to get a literal containing a single apostrophe, so you have to resort to a variable:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">   <xsl:template match="@*|node()">     <xsl:copy>       <xsl:apply-templates select="@*|node()"/>     </xsl:copy>   </xsl:template>   <xsl:variable name="apos">'</xsl:variable>   <xsl:template match="text()">     <xsl:value-of select="translate(.,'&quot;',$apos)"/>   </xsl:template> </xsl:stylesheet>

Are all Spring Framework Java Configuration injection examples buggy?

In your test, you are comparing the two TestParent beans, not the single TestedChild bean.

Also, Spring proxies your @Configuration class so that when you call one of the @Bean annotated methods, it caches the result and always returns the same object on future calls.

See here:

Removing "http://" from a string

Try this out:

$url = 'http://techcrunch.com/startups/'; $url = str_replace(array('http://', 'https://'), '', $url);

EDIT:

Or, a simple way to always remove the protocol:

$url = 'https://www.google.com/'; $url = preg_replace('@^.+?\:\/\/@', '', $url);

Cannot retrieve string(s) from preferences (settings)

All your exercise conditionals are separate and the else is only tied to the last if statement. Use else if to bind them all together in the way I believe you intend.

Got a NumberFormatException while trying to parse a text file for objects

The problem might be your split() call. Try just split(" ") without the square brackets.

Uploading into folder in FTP?

The folder is part of the URL you set when you create request: "ftp://www.contoso.com/test.htm". If you use "ftp://www.contoso.com/wibble/test.htm" then the file will be uploaded to a folder named wibble.

You may need to first use a request with Method = WebRequestMethods.Ftp.MakeDirectory to make the wibble folder if it doesn't already exist.

Real time face detection OpenCV, Python

Your line:

img = cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)

will draw a rectangle in the image, but the return value will be None, so img changes to None and cannot be drawn.

Try

cv2.rectangle(img,(x,y),(x+w,y+h),(255,0,0),2)

500 Error on AppHarbor but downloaded build works on my machine

Just a wild guess: (not much to go on) but I have had similar problems when, for example, I was using the IIS rewrite module on my local machine (and it worked fine), but when I uploaded to a host that did not have that add-on module installed, I would get a 500 error with very little to go on - sounds similar. It drove me crazy trying to find it.

So make sure whatever options/addons that you might have and be using locally in IIS are also installed on the host.

Similarly, make sure you understand everything that is being referenced/used in your web.config - that is likely the problem area.

Drag and drop menuitems

jQuery UI draggable and droppable are the two plugins I would use to achieve this effect. As for the insertion marker, I would investigate modifying the div (or container) element that was about to have content dropped into it. It should be possible to modify the border in some way or add a JavaScript/jQuery listener that listens for the hover (element about to be dropped) event and modifies the border or adds an image of the insertion marker in the right place.

php & mysql query not echoing in html with tags?

Change <?php echo $proxy ?> to ' . $proxy . '.

You use <?php when you're outputting HTML by leaving PHP mode with ?>. When you using echo, you have to use concatenation, or wrap your string in double quotes and use interpolation.

Target class controller does not exist - Laravel 8

I got the same error when I installed Laravel version 8.27.0: The error is as follow:

The Error that I got:

But when I saw my app/Providers/RouteServiceProvider.php I have namespaces inside my boot method, then I just uncommented this => "protected $namespace = 'App\Http\Controllers';"

Just Uncomment The protected $namespace = 'App\Http\Controllers';';

Now My Project is working:

Project is working safe and sound

When adding a Javascript library, Chrome complains about a missing source map, why?

While, the fix as per Valeri works, but its only for tfjs.

If you're expecting for body-pix or any other tensor-flow/models, you would be facing the same. It is an open issue too and the team is working on the fix!

https://github.com/dequelabs/axe-core/issues/1977

But, if you don't have problem in degrading the version (if anyone wants to use body-pix) from latest docs, below both links works fine as I've tested the same:

<script src="https://cdn.jsdelivr.net/npm/@tensorflow/[email protected]/dist/tf.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/@tensorflow-models/[email protected]"></script>

error NG6002: Appears in the NgModule.imports of AppModule, but could not be resolved to an NgModule class

I got this error when I made the bonehead mistake of importing MatSnackBar instead of MatSnackBarModule in app.module.ts.

TS1086: An accessor cannot be declared in ambient context

I had this error when i deleted several components while the server was on(after running the ng serve command). Although i deleted the references from the routes component and module, it didnt solve the problem. Then i followed these steps:

  1. Ended the server
  2. Restored those files
  3. Ran the ng serve command (at this point it solved the error)
  4. Ended the server
  5. Deleted the components which previously led to the error
  6. Ran the ng serve command (At this point no error as well).

Replace specific text with a redacted version using Python

You can do it using named-entity recognition (NER). It's fairly simple and there are out-of-the-shelf tools out there to do it, such as spaCy.

NER is an NLP task where a neural network (or other method) is trained to detect certain entities, such as names, places, dates and organizations.

Example:

Sponge Bob went to South beach, he payed a ticket of $200!
I know, Michael is a good person, he goes to McDonalds, but donates to charity at St. Louis street.

Returns:

NER with spacy

Just be aware that this is not 100%!

Here are a little snippet for you to try out:

import spacy

phrases = ['Sponge Bob went to South beach, he payed a ticket of $200!', 'I know, Michael is a good person, he goes to McDonalds, but donates to charity at St. Louis street.']
nlp = spacy.load('en')
for phrase in phrases:
   doc = nlp(phrase)
   replaced = ""
   for token in doc:
      if token in doc.ents:
         replaced+="XXXX "
      else:
         replaced+=token.text+" "

Read more here: https://spacy.io/usage/linguistic-features#named-entities

You could, instead of replacing with XXXX, replace based on the entity type, like:

if ent.label_ == "PERSON":
   replaced += "<PERSON> "

Then:

import re, random

personames = ["Jack", "Mike", "Bob", "Dylan"]

phrase = re.replace("<PERSON>", random.choice(personames), phrase)

Template not provided using create-react-app

I fix this issue on Mac by uninstalling create-react-app from global npm lib, that's basically what said, just try to do, you need also do sudo:

sudo npm uninstall -g create-react-app

Then simply run:

npx create-react-app my-app-name

Now should be all good and get the folder structures as below:

template not provided using create react app

Array and string offset access syntax with curly braces is deprecated

It's really simple to fix the issue, however keep in mind that you should fork and commit your changes for each library you are using in their repositories to help others as well.

Let's say you have something like this in your code:

$str = "test";
echo($str{0});

since PHP 7.4 curly braces method to get individual characters inside a string has been deprecated, so change the above syntax into this:

$str = "test";
echo($str[0]);

Fixing the code in the question will look something like this:

public function getRecordID(string $zoneID, string $type = '', string $name = ''): string
{
    $records = $this->listRecords($zoneID, $type, $name);
    if (isset($records->result[0]->id)) {
        return $records->result[0]->id;
    }
    return false;
}

Visual Studio Code PHP Intelephense Keep Showing Not Necessary Error

1.3.1 fixed it.

Just update your extension and you should be good to go

Unable to allocate array with shape and data type

change the data type to another one which uses less memory works. For me, I change the data type to numpy.uint8:

data['label'] = data['label'].astype(np.uint8)

Element implicitly has an 'any' type because expression of type 'string' can't be used to index

I made some small changes to Alex McKay's function/usage that I think make it a little easier to follow why it works and also adheres to the no-use-before-define rule.

First, define this function to use:

const getKeyValue = function<T extends object, U extends keyof T> (obj: T, key: U) { return obj[key] }

In the way I've written it, the generic for the function lists the object first, then the property on the object second (these can occur in any order, but if you specify U extends key of T before T extends object you break the no-use-before-define rule, and also it just makes sense to have the object first and its' property second. Finally, I've used the more common function syntax instead of the arrow operators (=>).

Anyways, with those modifications you can just use it like this:

interface User {
  name: string;
  age: number;
}

const user: User = {
  name: "John Smith",
  age: 20
};

getKeyValue(user, "name")

Which, again, I find to be a bit more readable.

"UserWarning: Matplotlib is currently using agg, which is a non-GUI backend, so cannot show the figure." when plotting figure with pyplot on Pycharm

The comment by @xicocaio should be highlighted.

tkinter is python version-specific in the sense that sudo apt-get install python3-tk will install tkinter exclusively for your default version of python. Suppose you have different python versions within various virtual environments, you will have to install tkinter for the desired python version used in that virtual environment. For example, sudo apt-get install python3.7-tk. Not doing this will still lead to No module named ' tkinter' errors, even after installing it for the global python version.

Schema validation failed with the following errors: Data path ".builders['app-shell']" should have required property 'class'

This is worked for me

  1. npm uninstall @angular-devkit/build-angular
  2. npm install @angular-devkit/[email protected]

Make a VStack fill the width of the screen in SwiftUI

This is a useful bit of code:

extension View {
    func expandable () -> some View {
        ZStack {
            Color.clear
            self
        }
    }
}

Compare the results with and without the .expandable() modifier:

Text("hello")
    .background(Color.blue)

-

Text("hello")
    .expandable()
    .background(Color.blue)

enter image description here

Why am I getting Unknown error in line 1 of pom.xml?

whenever you facing this type of error simply change the Release version just like In my case it is showing Error in 2.2.7 I changed to 2.2.6

Problem:

<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.7.RELEASE</version>

Solution:

<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.6.RELEASE</version>

How to fix 'Object arrays cannot be loaded when allow_pickle=False' for imdb.load_data() function?

Instead of

from keras.datasets import imdb

use

from tensorflow.keras.datasets import imdb

top_words = 10000
((x_train, y_train), (x_test, y_test)) = imdb.load_data(num_words=top_words, seed=21)

Module 'tensorflow' has no attribute 'contrib'

This issue might be helpful for you, it explains how to achieve TPUStrategy, a popular functionality of tf.contrib in TF<2.0.

So, in TF 1.X you could do the following:

resolver = tf.contrib.cluster_resolver.TPUClusterResolver('grpc://' + os.environ['COLAB_TPU_ADDR'])
tf.contrib.distribute.initialize_tpu_system(resolver)
strategy = tf.contrib.distribute.TPUStrategy(resolver)

And in TF>2.0, where tf.contrib is deprecated, you achieve the same by:

tf.config.experimental_connect_to_host('grpc://' + os.environ['COLAB_TPU_ADDR'])
resolver = tf.distribute.cluster_resolver.TPUClusterResolver('grpc://' + os.environ['COLAB_TPU_ADDR'])
tf.tpu.experimental.initialize_tpu_system(resolver)
strategy = tf.distribute.experimental.TPUStrategy(resolver)

How to fix missing dependency warning when using useEffect React Hook?

Well if you want to look into this differently, you just need to know what are options does the React has that non exhaustive-deps? One of the reason you should not use a closure function inside the effect is on every render, it will be re-created/destroy again.

So there are multiple React methods in hooks that is considered stable and non-exhausted where you do not have to apply to the useEffect dependencies, and in turn will not break the rules engagement of react-hooks/exhaustive-deps. For example the second return variable of useReducer or useState which is a function.

const [,dispatch] = useReducer(reducer, {});

useEffect(() => {
    dispatch(); // non-exhausted, eslint won't nag about this
}, []);

So in turn you can have all your external dependencies together with your current dependencies coexist together within your reducer function.

const [,dispatch] = useReducer((current, update) => {
    const { foobar } = update;
    // logic

    return { ...current, ...update };
}), {});

const [foobar, setFoobar] = useState(false);

useEffect(() => {
    dispatch({ foobar }); // non-exhausted `dispatch` function
}, [foobar]);

React Native Error: ENOSPC: System limit for number of file watchers reached

delete react node_modules

rm -r node_modules

yarn or npm install

yarn start or npm start

if error occurs use this method again

Module not found: Error: Can't resolve 'core-js/es6'

The imports have changed for core-js version 3.0.1 - for example

import 'core-js/es6/array'; and import 'core-js/es7/array';

can now be provided simply by the following

import 'core-js/es/array';

if you would prefer not to bring in the whole of core-js

Updating Anaconda fails: Environment Not Writable Error

On Windows, search for Anaconda PowerShell Prompt. Right click the program and select Run as administrator. In the command prompt, execute the following command:

conda update -n base -c defaults conda

Your Anaconda should now update without admin related errors.

Tensorflow 2.0 - AttributeError: module 'tensorflow' has no attribute 'Session'

TF2 runs Eager Execution by default, thus removing the need for Sessions. If you want to run static graphs, the more proper way is to use tf.function() in TF2. While Session can still be accessed via tf.compat.v1.Session() in TF2, I would discourage using it. It may be helpful to demonstrate this difference by comparing the difference in hello worlds:

TF1.x hello world:

import tensorflow as tf
msg = tf.constant('Hello, TensorFlow!')
sess = tf.Session()
print(sess.run(msg))

TF2.x hello world:

import tensorflow as tf
msg = tf.constant('Hello, TensorFlow!')
tf.print(msg)

For more info, see Effective TensorFlow 2

Typescript: Type 'string | undefined' is not assignable to type 'string'

I know this is kinda late answer but another way besides yannick's answer https://stackoverflow.com/a/57062363/6603342 to use ! is to cast it as string thus telling TypeScript i am sure this is a string thus converting

let name1:string = person.name;//<<<Error here

to

let name1:string = person.name as string;

This will make the error go away but if by any chance this is not a string you will get a run-time error which is one of the reassons we are using TypeScript to ensure that the type matches and avoid such errors at compile time.

Typescript: Type X is missing the following properties from type Y length, pop, push, concat, and 26 more. [2740]

I had the same problem and I solved as follows define an interface like mine

export class Notification {
    id: number;
    heading: string;
    link: string;
}

and in nofificationService write

allNotifications: Notification[]; 
  //NotificationDetail: Notification;  
  private notificationsUrl = 'assets/data/notification.json';  // URL to web api 
  private downloadsUrl = 'assets/data/download.json';  // URL to web api 

  constructor(private httpClient: HttpClient ) { }

  getNotifications(): Observable<Notification[]> {    
       //return this.allNotifications = this.NotificationDetail.slice(0);  
     return this.httpClient.get<Notification[]>

(this.notificationsUrl).pipe(map(res => this.allNotifications = res))
      }

and in component write

 constructor(private notificationService: NotificationService) {
   }

  ngOnInit() {
      /* get Notifications */
      this.notificationService.getNotifications().subscribe(data => this.notifications = data);
}

Gradle: Could not determine java version from '11.0.2'

I ran into the same issue in Ubuntu 18.04.3 LTS. In my case, apt installed gradle version 4.4.1. The already-install java version was 11.0.4

The build message I got was

Could not determine java version from '11.0.4'.

At the time, most of the online docs referenced gradle version 5.6, so I did the following:

sudo add-apt-repository ppa:cwchien/gradle
sudo apt update
sudo apt upgrade gradle

Then I repeated the project initialiation (using "gradle init" with the defaults). After that, "./gradlew build" worked correctly.

I later read a comment regarding a change in format of the output from "java --version" that caused gradle to break, which was fixed in a later version of gradle.

OpenCV TypeError: Expected cv::UMat for argument 'src' - What is this?

 
gray = cv2.cvtColor(cv2.UMat(imgUMat), cv2.COLOR_RGB2GRAY)

UMat is a part of the Transparent API (TAPI) than help to write one code for the CPU and OpenCL implementations.

Git fatal: protocol 'https' is not supported

Just add this git config --global http.sslVerify false , so that it doesn't check the certificate and it should work just fine

Can't perform a React state update on an unmounted component

I had this warning possibly because of calling setState from an effect hook (This is discussed in these 3 issues linked together).

Anyway, upgrading the react version removed the warning.

Pylint "unresolved import" error in Visual Studio Code

Alternative way: use the command interface!

Cmd/Ctrl + Shift + P ? Python: Select Interpreter ? choose the one with the packages you look for:

Enter image description here

TypeScript and React - children type?

You can use ReactChildren and ReactChild:

import React, { ReactChildren, ReactChild } from 'react';
 
interface AuxProps {
  children: ReactChild | ReactChildren;
}

const Aux = ({ children }: AuxProps) => (<div>{children}</div>);

export default Aux;

If you need to pass flat arrays of elements:

interface AuxProps {
  children: ReactChild | ReactChild[] | ReactChildren | ReactChildren[];
}

Pandas Merging 101

A supplemental visual view of pd.concat([df0, df1], kwargs). Notice that, kwarg axis=0 or axis=1 's meaning is not as intuitive as df.mean() or df.apply(func)

on pd.concat([df0, df1])

Why is 2 * (i * i) faster than 2 * i * i in Java?

Interesting observation using Java 11 and switching off loop unrolling with the following VM option:

-XX:LoopUnrollLimit=0

The loop with the 2 * (i * i) expression results in more compact native code1:

L0001: add    eax,r11d
       inc    r8d
       mov    r11d,r8d
       imul   r11d,r8d
       shl    r11d,1h
       cmp    r8d,r10d
       jl     L0001

in comparison with the 2 * i * i version:

L0001: add    eax,r11d
       mov    r11d,r8d
       shl    r11d,1h
       add    r11d,2h
       inc    r8d
       imul   r11d,r8d
       cmp    r8d,r10d
       jl     L0001

Java version:

java version "11" 2018-09-25
Java(TM) SE Runtime Environment 18.9 (build 11+28)
Java HotSpot(TM) 64-Bit Server VM 18.9 (build 11+28, mixed mode)

Benchmark results:

Benchmark          (size)  Mode  Cnt    Score     Error  Units
LoopTest.fast  1000000000  avgt    5  694,868 ±  36,470  ms/op
LoopTest.slow  1000000000  avgt    5  769,840 ± 135,006  ms/op

Benchmark source code:

@BenchmarkMode(Mode.AverageTime)
@OutputTimeUnit(TimeUnit.MILLISECONDS)
@Warmup(iterations = 5, time = 5, timeUnit = TimeUnit.SECONDS)
@Measurement(iterations = 5, time = 5, timeUnit = TimeUnit.SECONDS)
@State(Scope.Thread)
@Fork(1)
public class LoopTest {

    @Param("1000000000") private int size;

    public static void main(String[] args) throws RunnerException {
        Options opt = new OptionsBuilder()
            .include(LoopTest.class.getSimpleName())
            .jvmArgs("-XX:LoopUnrollLimit=0")
            .build();
        new Runner(opt).run();
    }

    @Benchmark
    public int slow() {
        int n = 0;
        for (int i = 0; i < size; i++)
            n += 2 * i * i;
        return n;
    }

    @Benchmark
    public int fast() {
        int n = 0;
        for (int i = 0; i < size; i++)
            n += 2 * (i * i);
        return n;
    }
}

1 - VM options used: -XX:+UnlockDiagnosticVMOptions -XX:+PrintAssembly -XX:LoopUnrollLimit=0

What is the meaning of "Failed building wheel for X" in pip install?

Yesterday, I got the same error: Failed building wheel for hddfancontrol when I ran pip3 install hddfancontrol. The result was Failed to build hddfancontrol. The cause was error: invalid command 'bdist_wheel' and Running setup.py bdist_wheel for hddfancontrol ... error. The error was fixed by running the following:

 pip3 install wheel

(From here.)

Alternatively, the "wheel" can be downloaded directly from here. When downloaded, it can be installed by running the following:

pip3 install "/the/file_path/to/wheel-0.32.3-py2.py3-none-any.whl"

Set the space between Elements in Row Flutter

There are many ways of doing it, I'm listing a few here:

  1. Use SizedBox if you want to set some specific space

    Row(
  children: <Widget>[
    Text("1"),
    SizedBox(width: 50), // give it width
    Text("2"),
  ],
)

    enter image description here

  1. Use Spacer if you want both to be as far apart as possible. 

    Row(
  children: <Widget>[
    Text("1"),
    Spacer(), // use Spacer
    Text("2"),
  ],
)

    enter image description here

  1. Use mainAxisAlignment according to your needs:

    Row(
  mainAxisAlignment: MainAxisAlignment.spaceEvenly, // use whichever suits your need
  children: <Widget>[
    Text("1"),
    Text("2"),
  ],
)

    enter image description here

  1. Use Wrap instead of Row and give some spacing

    Wrap(
  spacing: 100, // set spacing here
  children: <Widget>[
    Text("1"),
    Text("2"),
  ],
)

    enter image description here

  1. Use Wrap instead of Row and give it alignment

    Wrap(
  alignment: WrapAlignment.spaceAround, // set your alignment
  children: <Widget>[
    Text("1"),
    Text("2"),
  ],
)

    enter image description here

Flutter: RenderBox was not laid out

The problem is that you are placing the ListView inside a Column/Row. The text in the exception gives a good explanation of the error.

To avoid the error you need to provide a size to the ListView inside.

I propose you this code that uses an Expanded to inform the horizontal size (maximum available) and the SizedBox (Could be a Container) for the height:

    new Row(
      children: <Widget>[
        Expanded(
          child: SizedBox(
            height: 200.0,
            child: new ListView.builder(
              scrollDirection: Axis.horizontal,
              itemCount: products.length,
              itemBuilder: (BuildContext ctxt, int index) {
                return new Text(products[index]);
              },
            ),
          ),
        ),
        new IconButton(
          icon: Icon(Icons.remove_circle),
          onPressed: () {},
        ),
      ],
      mainAxisAlignment: MainAxisAlignment.spaceBetween,
    )

,

Space between Column's children in Flutter

There are many ways of doing it, I'm listing a few here.

  1. Use Container and give some height:

    Column(
  children: <Widget>[
    Widget1(),
    Container(height: 10), // set height
    Widget2(),
  ],
)

  2. Use Spacer

    Column(
  children: <Widget>[
    Widget1(),
    Spacer(), // use Spacer
    Widget2(),
  ],
)

  3. Use Expanded

    Column(
  children: <Widget>[
    Widget1(),
    Expanded(child: SizedBox()), // use Expanded
    Widget2(),
  ],
)

  4. Use mainAxisAlignment

    Column(
  mainAxisAlignment: MainAxisAlignment.spaceAround, // mainAxisAlignment
  children: <Widget>[
    Widget1(),
    Widget2(),
  ],
)

  5. Use Wrap 

    Wrap(
  direction: Axis.vertical, // make sure to set this
  spacing: 20, // set your spacing
  children: <Widget>[
    Widget1(),
    Widget2(),
  ],
)

How do I install Java on Mac OSX allowing version switching?

With Homebrew and jenv:

Assumption: Mac machine and you already have installed homebrew.

Install cask:

$ brew tap caskroom/cask
$ brew tap caskroom/versions

To install latest java:

$ brew cask install java

To install java 8:

$ brew cask install java8

To install java 9:

$ brew cask install java9

If you want to install/manage multiple version then you can use 'jenv':

Install and configure jenv:

$ brew install jenv
$ echo 'export PATH="$HOME/.jenv/bin:$PATH"' >> ~/.bash_profile
$ echo 'eval "$(jenv init -)"' >> ~/.bash_profile
$ source ~/.bash_profile

Add the installed java to jenv:

$ jenv add /Library/Java/JavaVirtualMachines/jdk1.8.0_202.jdk/Contents/Home
$ jenv add /Library/Java/JavaVirtualMachines/jdk1.11.0_2.jdk/Contents/Home

To see all the installed java:

$ jenv versions

Above command will give the list of installed java:

* system (set by /Users/lyncean/.jenv/version)
1.8
1.8.0.202-ea
oracle64-1.8.0.202-ea

Configure the java version which you want to use:

$ jenv global oracle64-1.6.0.39

Java 11 package javax.xml.bind does not exist

According to the release-notes, Java 11 removed the Java EE modules:

java.xml.bind (JAXB) - REMOVED
  • Java 8 - OK
  • Java 9 - DEPRECATED
  • Java 10 - DEPRECATED
  • Java 11 - REMOVED

See JEP 320 for more info.

You can fix the issue by using alternate versions of the Java EE technologies. Simply add Maven dependencies that contain the classes you need:

<dependency>
  <groupId>javax.xml.bind</groupId>
  <artifactId>jaxb-api</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-core</artifactId>
  <version>2.3.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.0</version>
</dependency>

Jakarta EE 8 update (Mar 2020)

Instead of using old JAXB modules you can fix the issue by using Jakarta XML Binding from Jakarta EE 8:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>2.3.3</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>2.3.3</version>
  <scope>runtime</scope>
</dependency>

Jakarta EE 9 update (Nov 2020)

Use latest release of Eclipse Implementation of JAXB 3.0.0:

<dependency>
  <groupId>jakarta.xml.bind</groupId>
  <artifactId>jakarta.xml.bind-api</artifactId>
  <version>3.0.0</version>
</dependency>
<dependency>
  <groupId>com.sun.xml.bind</groupId>
  <artifactId>jaxb-impl</artifactId>
  <version>3.0.0</version>
  <scope>runtime</scope>
</dependency>

Note: Jakarta EE 9 adopts new API package namespace jakarta.xml.bind.*, so update import statements:

javax.xml.bind -> jakarta.xml.bind

WARNING: API 'variant.getJavaCompile()' is obsolete and has been replaced with 'variant.getJavaCompileProvider()'

This is just a warning and it will probably be fixed before 2019 with plugin updates so don't worry about it. I would recommend you to use compatible versions of your plugins and gradle.

You can check your plugin version and gradle version here for better experience and performance.

https://developer.android.com/studio/releases/gradle-plugin

Try using the stable versions for a smooth and warning/error free code.

Jenkins pipeline how to change to another folder

You can use the dir step, example:

dir("folder") {
    sh "pwd"
}

The folder can be relative or absolute path.

I can't install pyaudio on Windows? How to solve "error: Microsoft Visual C++ 14.0 is required."?

If you have anaconda install than you just need to use command: conda install PyAudio.

In order to execute this command you must set thePYTHONPATH environment variable in anaconda.

DeprecationWarning: Buffer() is deprecated due to security and usability issues when I move my script to another server

The use of the deprecated new Buffer() constructor (i.E. as used by Yarn) can cause deprecation warnings. Therefore one should NOT use the deprecated/unsafe Buffer constructor.

According to the deprecation warning new Buffer() should be replaced with one of:

  • Buffer.alloc()
  • Buffer.allocUnsafe() or
  • Buffer.from()

Another option in order to avoid this issue would be using the safe-buffer package instead.

You can also try (when using yarn..):

yarn global add yarn

as mentioned here: Link

Another suggestion from the comments (thx to gkiely): self-update

Note: self-update is not available. See policies for enforcing versions within a project

In order to update your version of Yarn, run 

curl --compressed -o- -L https://yarnpkg.com/install.sh | bash

Android Material and appcompat Manifest merger failed

Simple Solutions - migrate into AndroidX

in the gradle.properties, just add below two scripts

android.useAndroidX=true
android.enableJetifier=true

What was the reason ?

All packages in AndroidX live in a consistent namespace starting with the string androidx. The Support Library packages have been mapped into the corresponding androidx.* packages. For a full mapping of all the old classes and build artifacts to the new ones, see the Package Refactoring page.

Please see the Package Refactoring page

How to scroll page in flutter

Very easy if you are already using a statelessWidget checkOut my code

class _MyThirdPage extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Understanding Material-Cards'),
      ),
      body: SingleChildScrollView(
          child: Column(
        children: <Widget>[
          _buildStack(),
          _buildCard(),
          SingleCard(),
          _inkwellCard()
        ],
      )),
    );
  }
}

Find the smallest positive integer that does not occur in a given sequence

This my implementation in Swift 4 with 100% Score. It should be a pretty similar code in Java. Let me know what you think.

public func solution(_ A : inout [Int]) -> Int {
  let B = A.filter({ element in
    element > 0
  }).sorted()

  var result = 1
  for element in B {
    if element == result {
      result = result + 1
    } else if element > result {
      break
    }
  }

  return result
}

Codility Test Result

Confirm password validation in Angular 6

This question could be solved with a combination of these two answers: https://stackoverflow.com/a/43493648/6294072 and https://stackoverflow.com/a/47670892/6294072

So first of all, you would need a custom validator for checking the passwords, that could look like this:

checkPasswords(group: FormGroup) { // here we have the 'passwords' group
  const password = group.get('password').value;
  const confirmPassword = group.get('confirmPassword').value;

  return password === confirmPassword ? null : { notSame: true }     
}

and you would create a formgroup for your fields, instead of just two form controls, then mark that custom validator for your form group:

this.myForm = this.fb.group({
  password: ['', [Validators.required]],
  confirmPassword: ['']
}, { validators: this.checkPasswords })

and then as mentioned in other answer, the mat-error only shows if a FormControl is invalid, so you need an error state matcher:

export class MyErrorStateMatcher implements ErrorStateMatcher {
  isErrorState(control: FormControl | null, form: FormGroupDirective | NgForm | null): boolean {
    const invalidCtrl = !!(control?.invalid && control?.parent?.dirty);
    const invalidParent = !!(control?.parent?.invalid && control?.parent?.dirty);

    return invalidCtrl || invalidParent;
  }
}

in the above you can tweak when to show error message. I would only show message when the password field is touched. Also I would like above, remove the required validator from the confirmPassword field, since the form is not valid anyway if passwords do not match.

Then in component, create a new ErrorStateMatcher:

matcher = new MyErrorStateMatcher();

Finally, the template would look like this:

<form [formGroup]="myForm">
  <mat-form-field>
    <input matInput placeholder="New password" formControlName="password" required>
    <mat-error *ngIf="myForm.hasError('required', 'password')">
      Please enter your new password
    </mat-error>
  </mat-form-field>

  <mat-form-field>
    <input matInput placeholder="Confirm password" formControlName="confirmPassword" [errorStateMatcher]="matcher">
    <mat-error *ngIf="myForm.hasError('notSame')">
      Passwords do not match
    </mat-error>  
  </mat-form-field>
</form>

Here's a demo for you with the above code: StackBlitz

Flutter : Vertically center column

Another Solution!

If you want to set widgets in center vertical form, you can use ListView for it. for eg: I used three buttons and add them inside ListView which followed by

shrinkWrap: true -> With this ListView only occupies the space which needed. 

import 'package:flutter/material.dart';

class List extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final button1 =
        new RaisedButton(child: new Text("Button1"), onPressed: () {});
    final button2 =
        new RaisedButton(child: new Text("Button2"), onPressed: () {});
    final button3 =
        new RaisedButton(child: new Text("Button3"), onPressed: () {});
    final body = new Center(
      child: ListView(
        shrinkWrap: true,
        children: <Widget>[button1, button2, button3],
     ),
    );

    return new Scaffold(
        appBar: new AppBar(
          title: Text("Sample"),
        ),
        body: body);
  }
}    
void main() {
  runApp(new MaterialApp(
    home: List(),
  ));
}

Output: enter image description here

git clone: Authentication failed for <URL>

As the other answers suggest, editing/removing credentials in the Manage Windows Credentials work and does the job. However, you need to do this each time when the password changes or credentials do not work for some work. Using ssh key has been extremely useful for me where I don't have to bother about these again once I'm done creating a ssh-key and adding them on the server repository (github/bitbucket/gitlab).

Generating a new ssh-key

  1. Open Git Bash.

  2. Paste the text below, substituting in your repo's email address. $ ssh-keygen -t rsa -b 4096 -C "[email protected]"

  3. When you're prompted to "Enter a file in which to save the key," press Enter. This accepts the default file location.

  4. Then you'll be asked to type a secure passphrase. You can type a passphrase, hit enter and type the passphrase again.

Or, Hit enter twice for empty passphrase.

  1. Copy this on the clipboard:

    clip < ~/.ssh/id_rsa.pub

And then add this key into your repo's profile. For e.g, on github->setting->SSH keys -> paste the key that you coppied ad hit add

Ref: https://help.github.com/en/enterprise/2.15/user/articles/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent#generating-a-new-ssh-key

You're done once and for all!

Xcode couldn't find any provisioning profiles matching

What fixed it for me was plugging my iPhone and allowing it as a simulator destination. Doing so required my to register my iPhone in Apple Dev account and once that was done and I ran my project from Xcode on my iPhone everything fixed itself.

  1. Connect your iPhone to your Mac
  2. Xcode>Window>Devices & Simulators
  3. Add new under Devices and make sure "show are run destination" is ticked
  4. Build project and run it on your iPhone

How to resolve TypeError: can only concatenate str (not "int") to str

Use f-strings to resolve the TypeError

# the following line causes a TypeError
# test = 'Here is a test that can be run' + 15 + 'times'

# same intent with a f-string
i = 15

test = f'Here is a test that can be run {i} times'

print(test)

# output
'Here is a test that can be run 15 times'

i = 15
# t = 'test' + i  # will cause a TypeError

# should be
t = f'test{i}'

print(t)

# output
'test15'
  • The issue may be attempting to evaluate an expression where a variable is the string of a numeric.
  • Convert the string to an int.
  • This scenario is specific to this question
  • When iterating, it's important to be aware of the dtype
i = '15'
# t = 15 + i  # will cause a TypeError

# convert the string to int
t = 15 + int(i)
print(t)

# output
30

Note

  • The preceding part of the answer addresses the TypeError shown in the question title, which is why people seem to be coming to this question.
  • However, this doesn't resolve the issue in relation to the example provided by the OP, which is addressed below.

Original Code Issues

  • TypeError is caused because message type is a str.
  • The code iterates each character and attempts to add char, a str type, to an int
  • That issue can be resolved by converting char to an int
  • As the code is presented, secret_string needs to be initialized with 0 instead of "".
  • The code also results in a ValueError: chr() arg not in range(0x110000) because 7429146 is out of range for chr().
  • Resolved by using a smaller number
  • The output is not a string, as was intended, which leads to the Updated Code in the question.
message = input("Enter a message you want to be revealed: ")

secret_string = 0

for char in message:
    char = int(char)
    value = char + 742146
    secret_string += ord(chr(value))
    
print(f'\nRevealed: {secret_string}')

# Output
Enter a message you want to be revealed:  999

Revealed: 2226465

Updated Code Issues

  • message is now an int type, so for char in message: causes TypeError: 'int' object is not iterable
  • message is converted to int to make sure the input is an int.
  • Set the type with str()
  • Only convert value to Unicode with chr
  • Don't use ord
while True:
    try:
        message = str(int(input("Enter a message you want to be decrypt: ")))
        break
    except ValueError:
        print("Error, it must be an integer")
        
secret_string = ""
for char in message:
    
    value = int(char) + 10000
    
    secret_string += chr(value)

print("Decrypted", secret_string)

# output
Enter a message you want to be decrypt:  999
Decrypted ???

Enter a message you want to be decrypt:  100
Decrypted ???

TypeError: only integer scalar arrays can be converted to a scalar index with 1D numpy indices array

I get this error whenever I use np.concatenate the wrong way:

>>> a = np.eye(2)
>>> np.concatenate(a, a)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<__array_function__ internals>", line 6, in concatenate
TypeError: only integer scalar arrays can be converted to a scalar index

The correct way is to input the two arrays as a tuple:

>>> np.concatenate((a, a))
array([[1., 0.],
       [0., 1.],
       [1., 0.],
       [0., 1.]])

Axios having CORS issue

your server should enable the cross origin requests, not the client. To do this, you can check this nice page with implementations and configurations for multiple platforms

How to add image in Flutter

I think the error is caused by the redundant ,

flutter:
  uses-material-design: true, # <<< redundant , at the end of the line
  assets:
    - images/lake.jpg

I'd also suggest to create an assets folder in the directory that contains the pubspec.yaml file and move images there and use

flutter:
  uses-material-design: true
  assets:
    - assets/images/lake.jpg

The assets directory will get some additional IDE support that you won't have if you put assets somewhere else.

Android design support library for API 28 (P) not working

Note: You should not use the com.android.support and com.google.android.material dependencies in your app at the same time.

Add Material Components for Android in your build.gradle(app) file

dependencies {
    // ...
    implementation 'com.google.android.material:material:1.0.0-beta01'
    // ...
  }

If your app currently depends on the original Design Support Library, you can make use of the Refactor to AndroidX… option provided by Android Studio. Doing so will update your app’s dependencies and code to use the newly packaged androidx and com.google.android.material libraries.

If you don’t want to switch over to the new androidx and com.google.android.material packages yet, you can use Material Components via the com.android.support:design:28.0.0-alpha3 dependency.

Xcode 10 Error: Multiple commands produce

This issue arose for me after adding a second part of the Fabric suite of SDKs to the app.

What actually happened was that the GoogleUtilies Framework was added twice to the Pods project

Two entries for GoogleUtilities.framework

This would have been fine prior to Xcode 10 but Xcode 10 will complain if a file has two actions against it (in this case a copy action).

It's safe to remove the second framework.

Set default option in mat-select

Using Form Model (Reactive Forms)

--- Html code--
<form [formGroup]="patientCategory">
<mat-form-field class="full-width">
    <mat-select placeholder="Category" formControlName="patientCategory">
        <mat-option>--</mat-option>
        <mat-option *ngFor="let category of patientCategories" [value]="category">
            {{category.name}} 
        </mat-option>
    </mat-select>
</mat-form-field>

----ts code ---

ngOnInit() {

        this.patientCategory = this.fb.group({
            patientCategory: [null, Validators.required]
        });

      const toSelect = "Your Default Value";
      this.patientCategory.get('patientCategory').setValue(toSelect);
    }

With out form Model

--- html code --
<mat-form-field>
  <mat-label>Select an option</mat-label>
  <mat-select [(value)]="selected">
    <mat-option>None</mat-option>
    <mat-option value="option1">Option 1</mat-option>
    <mat-option value="option2">Option 2</mat-option>
    <mat-option value="option3">Option 3</mat-option>
  </mat-select>
</mat-form-field>

---- ts code -- selected = 'option1'; Here take care about type of the value assigning

WebDriverException: unknown error: DevToolsActivePort file doesn't exist while trying to initiate Chrome Browser

Old question but a similar issue nearly drove me to insanity so sharing my solution. None of the other suggestions fixed my issue.

When I updated my Docker image Chrome installation from an old version to Chrome 86, I got this error. My setup was not identical but we were instantiating Chrome through a selenium webdriver.

The solution was to pass the options as goog:chromeOptions hash instead of chromeOptions hash. I truly don't know if this was a Selenium, Chrome, Chromedriver, or some other update, but maybe some poor soul will find solace in this answer in the future.

Difference between npx and npm?

Introducing npx: an npm package runner

NPM - Manages packages but doesn't make life easy executing any.
NPX - A tool for executing Node packages.

NPX comes bundled with NPM version 5.2+

NPM by itself does not simply run any package. it doesn't run any package in a matter of fact. If you want to run a package using NPM, you must specify that package in your package.json file.

When executables are installed via NPM packages, NPM links to them:

  1. local installs have "links" created at ./node_modules/.bin/ directory.
  2. global installs have "links" created from the global bin/ directory (e.g. /usr/local/bin) on Linux or at %AppData%/npm on Windows.

Documentation you should read

NPM:

One might install a package locally on a certain project:

npm install some-package

Now let's say you want NodeJS to execute that package from the command line:

$ some-package

The above will fail. Only globally installed packages can be executed by typing their name only.

To fix this, and have it run, you must type the local path:

$ ./node_modules/.bin/some-package

You can technically run a locally installed package by editing your packages.json file and adding that package in the scripts section:

{
  "name": "whatever",
  "version": "1.0.0",
  "scripts": {
    "some-package": "some-package"
  }
}

Then run the script using npm run-script (or npm run):

npm run some-package

NPX:

npx will check whether <command> exists in $PATH, or in the local project binaries, and execute it. So, for the above example, if you wish to execute the locally-installed package some-package all you need to do is type:

npx some-package

Another major advantage of npx is the ability to execute a package which wasn't previously installed:

$ npx create-react-app my-app

The above example will generate a react app boilerplate within the path the command had run in, and ensures that you always use the latest version of a generator or build tool without having to upgrade each time you’re about to use it.

Use-Case Example:

npx command may be helpful in the script section of a package.json file, when it is unwanted to define a dependency which might not be commonly used or any other reason:

"scripts": {
    "start": "npx [email protected]",
    "serve": "npx http-server"
}

Call with: npm run serve

Related questions:

  1. How to use package installed locally in node_modules?
  2. NPM: how to source ./node_modules/.bin folder?
  3. How do you run a js file using npm scripts?

Python Pandas User Warning: Sorting because non-concatenation axis is not aligned

tl;dr:

concat and append currently sort the non-concatenation index (e.g. columns if you're adding rows) if the columns don't match. In pandas 0.23 this started generating a warning; pass the parameter sort=True to silence it. In the future the default will change to not sort, so it's best to specify either sort=True or False now, or better yet ensure that your non-concatenation indices match.

The warning is new in pandas 0.23.0:

In a future version of pandas pandas.concat() and DataFrame.append() will no longer sort the non-concatenation axis when it is not already aligned. The current behavior is the same as the previous (sorting), but now a warning is issued when sort is not specified and the non-concatenation axis is not aligned, link.

More information from linked very old github issue, comment by smcinerney :

When concat'ing DataFrames, the column names get alphanumerically sorted if there are any differences between them. If they're identical across DataFrames, they don't get sorted.

This sort is undocumented and unwanted. Certainly the default behavior should be no-sort.

After some time the parameter sort was implemented in pandas.concat and DataFrame.append:

sort : boolean, default None

Sort non-concatenation axis if it is not already aligned when join is 'outer'. The current default of sorting is deprecated and will change to not-sorting in a future version of pandas.

Explicitly pass sort=True to silence the warning and sort. Explicitly pass sort=False to silence the warning and not sort.

This has no effect when join='inner', which already preserves the order of the non-concatenation axis.

So if both DataFrames have the same columns in the same order, there is no warning and no sorting:

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['a', 'b'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['a', 'b'])

print (pd.concat([df1, df2]))
   a  b
0  1  0
1  2  8
0  4  7
1  5  3

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['b', 'a'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['b', 'a'])

print (pd.concat([df1, df2]))
   b  a
0  0  1
1  8  2
0  7  4
1  3  5

But if the DataFrames have different columns, or the same columns in a different order, pandas returns a warning if no parameter sort is explicitly set (sort=None is the default value):

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8]}, columns=['b', 'a'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3]}, columns=['a', 'b'])

print (pd.concat([df1, df2]))

FutureWarning: Sorting because non-concatenation axis is not aligned.

   a  b
0  1  0
1  2  8
0  4  7
1  5  3

print (pd.concat([df1, df2], sort=True))
   a  b
0  1  0
1  2  8
0  4  7
1  5  3

print (pd.concat([df1, df2], sort=False))
   b  a
0  0  1
1  8  2
0  7  4
1  3  5

If the DataFrames have different columns, but the first columns are aligned - they will be correctly assigned to each other (columns a and b from df1 with a and b from df2 in the example below) because they exist in both. For other columns that exist in one but not both DataFrames, missing values are created.

Lastly, if you pass sort=True, columns are sorted alphanumerically. If sort=False and the second DafaFrame has columns that are not in the first, they are appended to the end with no sorting:

df1 = pd.DataFrame({"a": [1, 2], "b": [0, 8], 'e':[5, 0]}, 
                    columns=['b', 'a','e'])
df2 = pd.DataFrame({"a": [4, 5], "b": [7, 3], 'c':[2, 8], 'd':[7, 0]}, 
                    columns=['c','b','a','d'])

print (pd.concat([df1, df2]))

FutureWarning: Sorting because non-concatenation axis is not aligned.

   a  b    c    d    e
0  1  0  NaN  NaN  5.0
1  2  8  NaN  NaN  0.0
0  4  7  2.0  7.0  NaN
1  5  3  8.0  0.0  NaN

print (pd.concat([df1, df2], sort=True))
   a  b    c    d    e
0  1  0  NaN  NaN  5.0
1  2  8  NaN  NaN  0.0
0  4  7  2.0  7.0  NaN
1  5  3  8.0  0.0  NaN

print (pd.concat([df1, df2], sort=False))

   b  a    e    c    d
0  0  1  5.0  NaN  NaN
1  8  2  0.0  NaN  NaN
0  7  4  NaN  2.0  7.0
1  3  5  NaN  8.0  0.0

In your code:

placement_by_video_summary = placement_by_video_summary.drop(placement_by_video_summary_new.index)
                                                       .append(placement_by_video_summary_new, sort=True)
                                                       .sort_index()

Can not find module “@angular-devkit/build-angular”

I struggled with the same problem just a minute ago. My project was generated using the v 1.6.0 of angular-cli.

npm update -g @angular/cli editing my package.json changing the line "@angular/cli": "1.6.0", to "@angular/cli": "^1.6.0", npm update did the trick.

Connection Java-MySql : Public Key Retrieval is not allowed

Give connection URL as jdbc:mysql://localhost:3306/hb_student_tracker?allowPublicKeyRetrieval=true&useSSL=false&serverTimezone=UTC

Local package.json exists, but node_modules missing

This issue can also raise when you change your system password but not the same updated on your .npmrc file that exist on path C:\Users\user_name, so update your password there too.

please check on it and run npm install first and then npm start.

Could not find module "@angular-devkit/build-angular"

add @angular-devkit/build-angular under your dev dependency and it will work, or you can also execute

npm install --save-dev @angular-devkit/build-angular

Angular 6 Material mat-select change method removed

For me (selectionChange) and the suggested (onSelectionChange) didn't work and I'm not using ReactiveForms. What I ended up doing was using the (valueChange) event like:

<mat-select (valueChange)="someFunction()">

And this worked for me

Angular 5 Button Submit On Enter Key Press

Try to use keyup.enter but make sure to use it inside your input tag

<input
  matInput
  placeholder="enter key word"
  [(ngModel)]="keyword"
  (keyup.enter)="addToKeywords()"
/>

virtualbox Raw-mode is unavailable courtesy of Hyper-V windows 10

You need to disable the windows Hyper-V feature and bcd. Then Virtual Box will run in latest Windows 10 versions (Jan-Mar 2018). Windows 10 Hyper-V is having clash on VirtualBox features.

I have resolved this by following steps-

  1. bcdedit /set hypervisorlaunchtype off
  2. Disable-WindowsOptionalFeature -Online -FeatureName Microsoft-Hyper-V-All
  3. Restart your windows

Detailed discussion on this are available at - https://forums.virtualbox.org/viewtopic.php?f=6&t=87237

Alternatively you can install linux (Ubuntu) in Windows 10 from the latest bash command - https://www.windowscentral.com/how-install-bash-shell-command-line-windows-10

How do I add a user when I'm using Alpine as a base image?

The commands are adduser and addgroup.

Here's a template for Docker you can use in busybox environments (alpine) as well as Debian-based environments (Ubuntu, etc.):

ENV USER=docker
ENV UID=12345
ENV GID=23456

RUN adduser \
    --disabled-password \
    --gecos "" \
    --home "$(pwd)" \
    --ingroup "$USER" \
    --no-create-home \
    --uid "$UID" \
    "$USER"

Note the following:

  • --disabled-password prevents prompt for a password
  • --gecos "" circumvents the prompt for "Full Name" etc. on Debian-based systems
  • --home "$(pwd)" sets the user's home to the WORKDIR. You may not want this.
  • --no-create-home prevents cruft getting copied into the directory from /etc/skel

The usage description for these applications is missing the long flags present in the code for adduser and addgroup.

The following long-form flags should work both in alpine as well as debian-derivatives:

adduser

BusyBox v1.28.4 (2018-05-30 10:45:57 UTC) multi-call binary.

Usage: adduser [OPTIONS] USER [GROUP]

Create new user, or add USER to GROUP

        --home DIR           Home directory
        --gecos GECOS        GECOS field
        --shell SHELL        Login shell
        --ingroup GRP        Group (by name)
        --system             Create a system user
        --disabled-password  Don't assign a password
        --no-create-home     Don't create home directory
        --uid UID            User id

One thing to note is that if --ingroup isn't set then the GID is assigned to match the UID. If the GID corresponding to the provided UID already exists adduser will fail.

addgroup

BusyBox v1.28.4 (2018-05-30 10:45:57 UTC) multi-call binary.

Usage: addgroup [-g GID] [-S] [USER] GROUP

Add a group or add a user to a group

        --gid GID  Group id
        --system   Create a system group

I discovered all of this while trying to write my own alternative to the fixuid project for running containers as the hosts UID/GID.

My entrypoint helper script can be found on GitHub.

The intent is to prepend that script as the first argument to ENTRYPOINT which should cause Docker to infer UID and GID from a relevant bind mount.

An environment variable "TEMPLATE" may be required to determine where the permissions should be inferred from.

(At the time of writing I don't have documentation for my script. It's still on the todo list!!)

phpMyAdmin on MySQL 8.0

I had this problem, did not find any ini file in Windows, but the solution that worked for me was very simple.
1. Open the mysql installer.
2. Reconfigure mysql server, it is the first link.
3. Go to authentication method.
4. Choose 'Legacy authentication'.
5. Give your password(next field).
6. Apply changes.

That's it, hope my solution works fine for you as well!

pip: no module named _internal

I just encountered the same problem and in my case, it turns out this is a conflict between the python installation in my virtualenv and the site-wide python (Ubuntu). What solves it for me is to run pip in this way, to force usage of the correct python installation (in my vortualenv):

python3 -m pip install PACKAGE

instead of 

pip3 install PACKAGE

I realised this when I tried to follow some of the answers here that suggest re-installing pip and the error output I got was pointing to an existing site-wide python library path although I had activated my virtualenv. Worth trying before deleting and re-installing stuff.

Error after upgrading pip: cannot import name 'main'

I used the following code to load a module that might need install, thus avoiding this error (which I also got) - using the latest Python and latest pip with no problem

try
  from colorama import Fore, Back, Style
except:
  !pip install colorama
  from colorama import Fore, Back, Style

Error: Local workspace file ('angular.json') could not be found

If all sorts of updating commando's won't do it. Try deleting package-lock.json. And then run npm install. Did the trick for me after going through tons of update commando's.

Uncaught (in promise): Error: StaticInjectorError(AppModule)[options]

If we need to move from one component to another service then we have to define that service into app.module providers array.

How to make flutter app responsive according to different screen size?

This class will help and then initialize the class with the init method.

import 'package:flutter/widgets.dart';

class SizeConfig {
  static MediaQueryData _mediaQueryData;
  static double screenWidth;
  static double screenHeight;
  static double blockSizeHorizontal;
  static double blockSizeVertical;
  static double _safeAreaHorizontal;
  static double _safeAreaVertical;
  static double safeBlockHorizontal;
  static double safeBlockVertical;

  void init(BuildContext context){
    _mediaQueryData = MediaQuery.of(context);
    screenWidth = _mediaQueryData.size.width;
    screenHeight = _mediaQueryData.size.height;
    blockSizeHorizontal = screenWidth/100;
    blockSizeVertical = screenHeight/100;
    _safeAreaHorizontal = _mediaQueryData.padding.left +
        _mediaQueryData.padding.right;
    _safeAreaVertical = _mediaQueryData.padding.top +
        _mediaQueryData.padding.bottom;
    safeBlockHorizontal = (screenWidth - _safeAreaHorizontal)/100;
    safeBlockVertical = (screenHeight - _safeAreaVertical)/100;
  }
}

then in your widgets dimension do this

Widget build(BuildContext context) {
    SizeConfig().init(context);
    return Container(
    height: SizeConfig.safeBlockVertical * 10, //10 for example
    width: SizeConfig.safeBlockHorizontal * 10, //10 for example
    );}

All the credits to this post author: https://medium.com/flutter-community/flutter-effectively-scale-ui-according-to-different-screen-sizes-2cb7c115ea0a

Default interface methods are only supported starting with Android N

My project use ButterKnife and Retro lambda, setting JavaVersion.VERSION_1_8 will not work. It always blames at ButterKnife static interface function until I found this Migrate from Retrolambda

TL;DR

Just add JavaVersion.VERSION_1_8 and completely REMOVE retrolambda from your project. It will build successfully.

Converting a POSTMAN request to Curl

enter image description here

You can see the button "Code" in the attached screenshot, press it and you can get your code in many different languages including PHP cURL

enter image description here

Error - Android resource linking failed (AAPT2 27.0.3 Daemon #0)

In your layout (xml) files almost every element has a property i.e. "id" which, can be assigned in order to refer to it from the java/kotlin code or from the xml itself.

Now sometimes or in some versions of Android Studio errors in xml files is either not reported or some random error is thrown while compiling, of which, this thread is an example i.e. when assigning an id to an element or when refering to another element in the layout we use the ID but ids are not just written like any other word rather they are prefixed by these characters: @+id/, otherwise the above error is thrown.

Hence the solution below should be considered:-

I resolved it by adding @+id/ before all my IDs.

i.e. @+id/your_item_id

did you register the component correctly? For recursive components, make sure to provide the "name" option

Wasted almost one hour, didn't find a solution, so I wanted to contribute =)

In my case, I was importing WRONGLY the component.. like below:

import { MyComponent } from './components/MyComponent'

But the CORRECT is (without curly braces):

import MyComponent from './components/MyComponent'

How to remove whitespace from a string in typescript?

The trim() method removes whitespace from both sides of a string.

To remove all the spaces from the string use .replace(/\s/g, "")

 this.maintabinfo = this.inner_view_data.replace(/\s/g, "").toLowerCase();

ERROR Source option 1.5 is no longer supported. Use 1.6 or later

I think this means that

  • You are using JDK9 or later
  • Your project uses maven-compiler-plugin with an old version which defaults to Java 5.

You have three options to solve this

  1. Downgrade to JDK7 or JDK8 (meh)

  2. Use maven-compiler-plugin version or later, because

    NOTE: Since 3.8.0 the default value has changed from 1.5 to 1.6 See https://maven.apache.org/plugins/maven-compiler-plugin/compile-mojo.html#target

    <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.8.0</version>
</plugin>

  3. Indicate to the maven-compiler-plugin to use source level 6 and target 6 (or later).

    Best practice recommended by https://maven.apache.org/plugins/maven-compiler-plugin/

    Also note that at present the default source setting is 1.6 and the default target setting is 1.6, independently of the JDK you run Maven with. You are highly encouraged to change these defaults by setting source and target as described in Setting the -source and -target of the Java Compiler.

    <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <configuration>
        <source>1.6</source>
        <target>1.6</target>
    </configuration>
</plugin>

    or use

    <properties>
  <maven.compiler.source>1.6</maven.compiler.source>
  <maven.compiler.target>1.6</maven.compiler.target>
</properties>

VSCode single to double quote automatic replace

Install prettier extension and paste below code in your VSCode settings.json file

 "prettier.useEditorConfig": false,
 "prettier.singleQuote": true

this will ignore your .editorconfig file setting.

js 'types' can only be used in a .ts file - Visual Studio Code using @ts-check

For anyone who lands here and all the other solutions did not work give this a try. I am using typescript + react and my problem was that I was associating the files in vscode as javascriptreact not typescriptreact so check your settings for the following entries. 

   "files.associations": {
    "*.tsx": "typescriptreact",
    "*.ts": "typescriptreact"
  },

Still getting warning : Configuration 'compile' is obsolete and has been replaced with 'implementation'

No need to remove the line. As Jkrevis wrote, update the com.google.gms:google-services to 3.2.0 and it stops the warnings.

Dart SDK is not configured

A quicker way..

Open up android studio..go the file menu....there u will find Invalidate caches/Restart..click it and respond to the pop up as Invalidate and Restart

Your android studio will get restarted.And its all done.

It really helped me.

ReactJS: Maximum update depth exceeded error

In this case , this code 

{<td><span onClick={this.toggle()}>Details</span></td>}

causes toggle function to call immediately and re render it again and again thus making infinite calls.

so passing only the reference to that toggle method will solve the problem.

so , 

{<td><span onClick={this.toggle}>Details</span></td>}

will be the solution code.

If you want to use the () , you should use an arrow function like this

{<td><span onClick={()=> this.toggle()}>Details</span></td>}

In case you want to pass parameters you should choose the last option and you can pass parameters like this 

{<td><span onClick={(arg)=>this.toggle(arg)}>Details</span></td>}

In the last case it doesn't call immediately and don't cause the re render of the function, hence avoiding infinite calls.

Bootstrap 4: responsive sidebar menu to top navbar

Big screen:

navigation side bar in big screen size

Small screen (Mobile)

sidebar in small mobile size screen

if this is what you wanted this is code https://plnkr.co/edit/PCCJb9f7f93HT4OubLmM?p=preview

CSS + HTML + JQUERY :

_x000D_
_x000D_ 
    _x000D_
    @import "https://fonts.googleapis.com/css?family=Poppins:300,400,500,600,700";_x000D_
    body {_x000D_
      font-family: 'Poppins', sans-serif;_x000D_
      background: #fafafa;_x000D_
    }_x000D_
    _x000D_
    p {_x000D_
      font-family: 'Poppins', sans-serif;_x000D_
      font-size: 1.1em;_x000D_
      font-weight: 300;_x000D_
      line-height: 1.7em;_x000D_
      color: #999;_x000D_
    }_x000D_
    _x000D_
    a,_x000D_
    a:hover,_x000D_
    a:focus {_x000D_
      color: inherit;_x000D_
      text-decoration: none;_x000D_
      transition: all 0.3s;_x000D_
    }_x000D_
    _x000D_
    .navbar {_x000D_
      padding: 15px 10px;_x000D_
      background: #fff;_x000D_
      border: none;_x000D_
      border-radius: 0;_x000D_
      margin-bottom: 40px;_x000D_
      box-shadow: 1px 1px 3px rgba(0, 0, 0, 0.1);_x000D_
    }_x000D_
    _x000D_
    .navbar-btn {_x000D_
      box-shadow: none;_x000D_
      outline: none !important;_x000D_
      border: none;_x000D_
    }_x000D_
    _x000D_
    .line {_x000D_
      width: 100%;_x000D_
      height: 1px;_x000D_
      border-bottom: 1px dashed #ddd;_x000D_
      margin: 40px 0;_x000D_
    }_x000D_
    /* ---------------------------------------------------_x000D_
    SIDEBAR STYLE_x000D_
----------------------------------------------------- */_x000D_
    _x000D_
    #sidebar {_x000D_
      width: 250px;_x000D_
      position: fixed;_x000D_
      top: 0;_x000D_
      left: 0;_x000D_
      height: 100vh;_x000D_
      z-index: 999;_x000D_
      background: #7386D5;_x000D_
      color: #fff !important;_x000D_
      transition: all 0.3s;_x000D_
    }_x000D_
    _x000D_
    #sidebar.active {_x000D_
      margin-left: -250px;_x000D_
    }_x000D_
    _x000D_
    #sidebar .sidebar-header {_x000D_
      padding: 20px;_x000D_
      background: #6d7fcc;_x000D_
    }_x000D_
    _x000D_
    #sidebar ul.components {_x000D_
      padding: 20px 0;_x000D_
      border-bottom: 1px solid #47748b;_x000D_
    }_x000D_
    _x000D_
    #sidebar ul p {_x000D_
      color: #fff;_x000D_
      padding: 10px;_x000D_
    }_x000D_
    _x000D_
    #sidebar ul li a {_x000D_
      padding: 10px;_x000D_
      font-size: 1.1em;_x000D_
      display: block;_x000D_
      color:white;_x000D_
    }_x000D_
    _x000D_
    #sidebar ul li a:hover {_x000D_
      color: #7386D5;_x000D_
      background: #fff;_x000D_
    }_x000D_
    _x000D_
    #sidebar ul li.active>a,_x000D_
    a[aria-expanded="true"] {_x000D_
      color: #fff;_x000D_
      background: #6d7fcc;_x000D_
    }_x000D_
    _x000D_
    a[data-toggle="collapse"] {_x000D_
      position: relative;_x000D_
    }_x000D_
    _x000D_
    a[aria-expanded="false"]::before,_x000D_
    a[aria-expanded="true"]::before {_x000D_
      content: '\e259';_x000D_
      display: block;_x000D_
      position: absolute;_x000D_
      right: 20px;_x000D_
      font-family: 'Glyphicons Halflings';_x000D_
      font-size: 0.6em;_x000D_
    }_x000D_
    _x000D_
    a[aria-expanded="true"]::before {_x000D_
      content: '\e260';_x000D_
    }_x000D_
    _x000D_
    ul ul a {_x000D_
      font-size: 0.9em !important;_x000D_
      padding-left: 30px !important;_x000D_
      background: #6d7fcc;_x000D_
    }_x000D_
    _x000D_
    ul.CTAs {_x000D_
      padding: 20px;_x000D_
    }_x000D_
    _x000D_
    ul.CTAs a {_x000D_
      text-align: center;_x000D_
      font-size: 0.9em !important;_x000D_
      display: block;_x000D_
      border-radius: 5px;_x000D_
      margin-bottom: 5px;_x000D_
    }_x000D_
    _x000D_
    a.download {_x000D_
      background: #fff;_x000D_
      color: #7386D5;_x000D_
    }_x000D_
    _x000D_
    a.article,_x000D_
    a.article:hover {_x000D_
      background: #6d7fcc !important;_x000D_
      color: #fff !important;_x000D_
    }_x000D_
    /* ---------------------------------------------------_x000D_
    CONTENT STYLE_x000D_
----------------------------------------------------- */_x000D_
    _x000D_
    #content {_x000D_
      width: calc(100% - 250px);_x000D_
      padding: 40px;_x000D_
      min-height: 100vh;_x000D_
      transition: all 0.3s;_x000D_
      position: absolute;_x000D_
      top: 0;_x000D_
      right: 0;_x000D_
    }_x000D_
    _x000D_
    #content.active {_x000D_
      width: 100%;_x000D_
    }_x000D_
    /* ---------------------------------------------------_x000D_
    MEDIAQUERIES_x000D_
----------------------------------------------------- */_x000D_
    _x000D_
    @media (max-width: 768px) {_x000D_
      #sidebar {_x000D_
        margin-left: -250px;_x000D_
      }_x000D_
      #sidebar.active {_x000D_
        margin-left: 0;_x000D_
      }_x000D_
      #content {_x000D_
        width: 100%;_x000D_
      }_x000D_
      #content.active {_x000D_
        width: calc(100% - 250px);_x000D_
      }_x000D_
      #sidebarCollapse span {_x000D_
        display: none;_x000D_
      }_x000D_
    }
_x000D_ 
<!DOCTYPE html>_x000D_
<html>_x000D_
_x000D_
<head>_x000D_
  <meta charset="utf-8">_x000D_
  <meta name="viewport" content="width=device-width, initial-scale=1.0">_x000D_
  <meta http-equiv="X-UA-Compatible" content="IE=edge">_x000D_
_x000D_
  <title>Collapsible sidebar using Bootstrap 3</title>_x000D_
_x000D_
  <!-- Bootstrap CSS CDN -->_x000D_
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">_x000D_
  <!-- Our Custom CSS -->_x000D_
  <link rel="stylesheet" href="style2.css">_x000D_
  <!-- Scrollbar Custom CSS -->_x000D_
  <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/malihu-custom-scrollbar-plugin/3.1.5/jquery.mCustomScrollbar.min.css">_x000D_
_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
_x000D_
_x000D_
_x000D_
  <div class="wrapper">_x000D_
    <!-- Sidebar Holder -->_x000D_
    <nav id="sidebar">_x000D_
      <div class="sidebar-header">_x000D_
        <h3>Header as you want </h3>_x000D_
        </h3>_x000D_
      </div>_x000D_
_x000D_
      <ul class="list-unstyled components">_x000D_
        <p>Dummy Heading</p>_x000D_
        <li class="active">_x000D_
          <a href="#menu">Animación</a>_x000D_
_x000D_
        </li>_x000D_
        <li>_x000D_
          <a href="#menu">Ilustración</a>_x000D_
_x000D_
_x000D_
        </li>_x000D_
        <li>_x000D_
          <a href="#menu">Interacción</a>_x000D_
        </li>_x000D_
        <li>_x000D_
          <a href="#">Blog</a>_x000D_
        </li>_x000D_
        <li>_x000D_
          <a href="#">Acerca</a>_x000D_
        </li>_x000D_
        <li>_x000D_
          <a href="#">contacto</a>_x000D_
        </li>_x000D_
_x000D_
_x000D_
      </ul>_x000D_
_x000D_
_x000D_
    </nav>_x000D_
_x000D_
    <!-- Page Content Holder -->_x000D_
    <div id="content">_x000D_
_x000D_
      <nav class="navbar navbar-default">_x000D_
        <div class="container-fluid">_x000D_
_x000D_
          <div class="navbar-header">_x000D_
            <button type="button" id="sidebarCollapse" class="btn btn-info navbar-btn">_x000D_
                                <i class="glyphicon glyphicon-align-left"></i>_x000D_
                                <span>Toggle Sidebar</span>_x000D_
                            </button>_x000D_
          </div>_x000D_
_x000D_
          <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">_x000D_
            <ul class="nav navbar-nav navbar-right">_x000D_
              <li><a href="#">Page</a></li>_x000D_
            </ul>_x000D_
          </div>_x000D_
        </div>_x000D_
      </nav>_x000D_
_x000D_
_x000D_
    </div>_x000D_
  </div>_x000D_
_x000D_
_x000D_
_x000D_
_x000D_
_x000D_
  <!-- jQuery CDN -->_x000D_
  <script src="https://code.jquery.com/jquery-1.12.0.min.js"></script>_x000D_
  <!-- Bootstrap Js CDN -->_x000D_
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>_x000D_
  <!-- jQuery Custom Scroller CDN -->_x000D_
  <script src="https://cdnjs.cloudflare.com/ajax/libs/malihu-custom-scrollbar-plugin/3.1.5/jquery.mCustomScrollbar.concat.min.js"></script>_x000D_
_x000D_
  <script type="text/javascript">_x000D_
    $(document).ready(function() {_x000D_
_x000D_
_x000D_
      $('#sidebarCollapse').on('click', function() {_x000D_
        $('#sidebar, #content').toggleClass('active');_x000D_
        $('.collapse.in').toggleClass('in');_x000D_
        $('a[aria-expanded=true]').attr('aria-expanded', 'false');_x000D_
      });_x000D_
    });_x000D_
  </script>_x000D_
</body>_x000D_
_x000D_
</html>
_x000D_
_x000D_
_x000D_

if this is what you want .

Assets file project.assets.json not found. Run a NuGet package restore

You will get required packages from "https://api.nuget.org/v3/index.json". Add this in Package Resources. Also make sure other packages are unchecked for time being. And Click Restore Nuget Package on Solution Explorer enter image description here

React Native: JAVA_HOME is not set and no 'java' command could be found in your PATH

It is located on the Android Studio folder itself, on where you installed it.

enter image description here

Changing directory in Google colab (breaking out of the python interpreter)

use

%cd SwitchFrequencyAnalysis

to change the current working directory for the notebook environment (and not just the subshell that runs your ! command).

you can confirm it worked with the pwd command like this:

!pwd

further information about jupyter / ipython magics: http://ipython.readthedocs.io/en/stable/interactive/magics.html#magic-cd

Issue in installing php7.2-mcrypt

I followed below steps to install mcrypt for PHP7.2 using PECL.

  1. Install PECL

apt-get install php-pecl

  1. Before installing MCRYPT you must install libmcrypt

apt-get install libmcrypt-dev libreadline-dev

  1. Install MCRYPT 1.0.1 using PECL

pecl install mcrypt-1.0.1

  1. After the successful installation

You should add "extension=mcrypt.so" to php.ini

Please comment below if you need any assistance. :-)

IMPORTANT !

According to php.net reference many (all) mcrypt functions have been DEPRECATED as of PHP 7.1.0. Relying on this function is highly discouraged.

Can (a== 1 && a ==2 && a==3) ever evaluate to true?

Actually the answer to the first part of the question is "Yes" in every programming language. For example, this is in the case of C/C++:

#define a   (b++)
int b = 1;
if (a ==1 && a== 2 && a==3) {
    std::cout << "Yes, it's possible!" << std::endl;
} else {
    std::cout << "it's impossible!" << std::endl;
}

document.getElementById replacement in angular4 / typescript?

You can just inject the DOCUMENT token into the constructor and use the same functions on it

import { Inject }  from '@angular/core';
import { DOCUMENT } from '@angular/common'; 

@Component({...})
export class AppCmp {
   constructor(@Inject(DOCUMENT) document) {
      document.getElementById('el');
   }
}

Or if the element you want to get is in that component, you can use template references.

Exclude property from type

For versions of TypeScript at or above 3.5

In TypeScript 3.5, the Omit type was added to the standard library. See examples below for how to use it.

For versions of TypeScript below 3.5

In TypeScript 2.8, the Exclude type was added to the standard library, which allows an omission type to be written simply as:

type Omit<T, K extends keyof T> = Pick<T, Exclude<keyof T, K>>

For versions of TypeScript below 2.8

You cannot use the Exclude type in versions below 2.8, but you can create a replacement for it in order to use the same sort of definition as above. However, this replacement will only work for string types, so it is not as powerful as Exclude.

// Functionally the same as Exclude, but for strings only.
type Diff<T extends string, U extends string> = ({[P in T]: P } & {[P in U]: never } & { [x: string]: never })[T]
type Omit<T, K extends keyof T> = Pick<T, Diff<keyof T, K>>

And an example of that type in use:

interface Test {
    a: string;
    b: number;
    c: boolean;
}

// Omit a single property:
type OmitA = Omit<Test, "a">; // Equivalent to: {b: number, c: boolean}

// Or, to omit multiple properties:
type OmitAB = Omit<Test, "a"|"b">; // Equivalent to: {c: boolean}

json.decoder.JSONDecodeError: Extra data: line 2 column 1 (char 190)

I was parsing JSON from a REST API call and got this error. It turns out the API had become "fussier" (eg about order of parameters etc) and so was returning malformed results. Check that you are getting what you expect :)

'mat-form-field' is not a known element - Angular 5 & Material2

Check the namespace from where we are importing

import { MatDialogModule } from **"@angular/material/dialog";**
import { MatCardModule } from **"@angular/material/card";**
import { MatButtonModule } from **"@angular/material/button";**

java.lang.IllegalStateException: Only fullscreen opaque activities can request orientation

I do not know if this is a bug from Google or an intended behavior but I (at least momentarily) solved it by changing compileSdkVersion and targetSdkVersion back to 26 in Gradle...

Python: Pandas pd.read_excel giving ImportError: Install xlrd >= 0.9.0 for Excel support

Since December 2020 xlrd no longer supports xlsx-Files as explained in the official changelog. You can use openpyxl instead:

pip install openpyxl

And in your python-file:

import pandas as pd
pd.read_excel('path/to/file.xlsx', engine='openpyxl')

phpmyadmin - count(): Parameter must be an array or an object that implements Countable

tested on Debian, should works on Ubuntu:

1.) First download latest phpMyadmin file.

2.) Delete (make a backup) all previous version file located in /usr/share/phpmyadmin directory.

3.) Uncompress to /usr/share/phpmyadmin/ directory all files of latest phpmyadmin.

4.) Modify file libraries/vendor_config.php and change line:

define('CONFIG_DIR', '');

to 

define('CONFIG_DIR', '/etc/phpmyadmin/');

and

define('TEMP_DIR', './tmp/');

to 

define('TEMP_DIR', '/tmp/');

5.) restart apache server and done.

How to access Anaconda command prompt in Windows 10 (64-bit)

How to add anaconda installation directory to your PATH variables

1. open environmental variables window

Do this by either going to my computer and then right clicking the background for the context menu > "properties". On the left side open "advanced system settings" or just search for "env..." in start menu ([Win]+[s] keys).

Then click on environment variables

If you struggle with this step read this explanation.

2. Edit Path in the user environmental variables section and add three new entries:

  • D:\path\to\anaconda3
  • D:\path\to\anaconda3\Scripts
  • D:\path\to\anaconda3\Library\bin

D:\path\to\anaconda3 should be the folder where you have installed anaconda

Click [OK] on all opened windows.

If you did everything correctly, you can test a conda command by opening a new powershell window.

conda --version

This should output something like: conda 4.8.2

How to shift a block of code left/right by one space in VSCode?

 
Current Version 1.38.1

I had a problem with intending. The default Command+] is set to 4 and I wanted it to be 2. Installed "Indent 4-to-2" but it changed the entire file and not the selected text.

I changed the tab spacing in settings and it was simple.

Go to Settings -> Text Editor -> Tab Size

Is ConfigurationManager.AppSettings available in .NET Core 2.0?

You can use Configuration to resolve this.

Ex (Startup.cs):

You can pass by DI to the controllers after this implementation.

public class Startup
{
    public Startup(IHostingEnvironment env)
    {
        var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true);

        Configuration = builder.Build();

    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {

        var microserviceName = Configuration["microserviceName"];

       services.AddSingleton(Configuration);

       ...
    }

Unable to import path from django.urls

For someone having the same problem -

import name 'path' from 'django.urls' 
(C:\Python38\lib\site-packages\django\urls\__init__.py)

You can also try installing django-urls by

pipenv install django-urls

regex match any single character (one character only)

Match any single character

  • Use the dot . character as a wildcard to match any single character.

Example regex: a.c

abc   // match
a c   // match
azc   // match
ac    // no match
abbc  // no match

Match any specific character in a set

  • Use square brackets [] to match any characters in a set.
  • Use \w to match any single alphanumeric character: 0-9, a-z, A-Z, and _ (underscore).
  • Use \d to match any single digit.
  • Use \s to match any single whitespace character.

Example 1 regex: a[bcd]c

abc   // match
acc   // match
adc   // match
ac    // no match
abbc  // no match

Example 2 regex: a[0-7]c

a0c   // match
a3c   // match
a7c   // match
a8c   // no match
ac    // no match
a55c  // no match

Match any character except ...

Use the hat in square brackets [^] to match any single character except for any of the characters that come after the hat ^.

Example regex: a[^abc]c

aac   // no match
abc   // no match
acc   // no match
a c   // match
azc   // match
ac    // no match
azzc  // no match

(Don't confuse the ^ here in [^] with its other usage as the start of line character: ^ = line start, $ = line end.)

Match any character optionally

Use the optional character ? after any character to specify zero or one occurrence of that character. Thus, you would use .? to match any single character optionally.

Example regex: a.?c

abc   // match
a c   // match
azc   // match
ac    // match
abbc  // no match

See also

Could not resolve com.android.support:appcompat-v7:26.1.0 in Android Studio new project

OK It's A Wrong Approach But If You Use it Like This :

compile "com.android.support:appcompat-v7:+"

Android Studio Will Use The Last Version It Has.

In My Case Was 26.0.0alpha-1.

You Can See The Used Version In External Libraries (In The Project View).

I Tried Everything But Couldn't Use Anything Above 26.0.0alpha-1, It Seems My IP Is Blocked By Google. Any Idea? Comment

kubectl apply vs kubectl create?

We love Kubernetes is because once we give them what we want it goes on to figure out how to achieve it without our any involvement.

"create" is like playing GOD by taking things into our own hands. It is good for local debugging when you only want to work with the POD and not care abt Deployment/Replication Controller.

"apply" is playing by the rules. "apply" is like a master tool that helps you create and modify and requires nothing from you to manage the pods.

No authenticationScheme was specified, and there was no DefaultChallengeScheme found with default authentification and custom authorization

When I used policy before I set the default authentication scheme into it as well. I had modified the DefaultPolicy so it was slightly different. However the same should work for add policy as well. 

services.AddAuthorization(options =>
        {
            options.AddPolicy(DefaultAuthorizedPolicy, policy =>
            {
                policy.Requirements.Add(new TokenAuthRequirement());
                policy.AuthenticationSchemes = new List<string>()
                                {
                                    CookieAuthenticationDefaults.AuthenticationScheme
                                }
            });
        });

Do take into consideration that by Default AuthenticationSchemes property uses a read only list. I think it would be better to implement that instead of List as well.

Save and load weights in keras

Here is a YouTube video that explains exactly what you're wanting to do: Save and load a Keras model

There are three different saving methods that Keras makes available. These are described in the video link above (with examples), as well as below.

First, the reason you're receiving the error is because you're calling load_model incorrectly.

To save and load the weights of the model, you would first use 

model.save_weights('my_model_weights.h5')

to save the weights, as you've displayed. To load the weights, you would first need to build your model, and then call load_weights on the model, as in

model.load_weights('my_model_weights.h5')

Another saving technique is model.save(filepath). This save function saves:

  • The architecture of the model, allowing to re-create the model.
  • The weights of the model.
  • The training configuration (loss, optimizer).
  • The state of the optimizer, allowing to resume training exactly where you left off.

To load this saved model, you would use the following:

from keras.models import load_model
new_model = load_model(filepath)'

Lastly, model.to_json(), saves only the architecture of the model. To load the architecture, you would use 

from keras.models import model_from_json
model = model_from_json(json_string)

How to import keras from tf.keras in Tensorflow?

Try from tensorflow.python import keras

with this, you can easily change keras dependent code to tensorflow in one line change.

You can also try from tensorflow.contrib import keras. This works on tensorflow 1.3

Edited: for tensorflow 1.10 and above you can use import tensorflow.keras as keras to get keras in tensorflow.

No provider for HttpClient

I was also facing similar issue by doing below changes, it worked for me

In app.modules.ts 

import {HttpClientModule} from '@angular/common/http'

and in corresponding service class 

import { HttpClient } from '@angular/common/http'

constructor should look like as below 

constructor(private http: HttpClient, private xyz: xyzService) {}

In test file 

import { HttpClientTestingModule } from '@angular/common/http/testing'

  beforeEach(() => TestBed.configureTestingModule({
    imports: [HttpClientTestingModule]
  }));

java.lang.RuntimeException: com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex in Android Studio 3.0

Enable Multidex through build.gradle of your app module

multiDexEnabled true

Same as below - 

android {
    compileSdkVersion 27
    defaultConfig {
        applicationId "com.xx.xxx"
        minSdkVersion 15
        targetSdkVersion 27
        versionCode 1
        versionName "1.0"
        multiDexEnabled true //Add this
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            shrinkResources true
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

Then follow below steps -

  1. From the Build menu -> press the Clean Project button.
  2. When task completed, press the Rebuild Project button from the Build menu.
  3. From menu File -> Invalidate cashes / Restart

compile is now deprecated so it's better to use implementation or api

Failed to run sdkmanager --list with Java 9

Update 2019-10:

As stated in the issue tracker, Google has been working on a new SDK tools release that runs on current JVMs (9+)!

You can download and use the new Android SDK Command-line Tools (1.0.0) inside Android Studio or by manually downloading them from the Google servers:

For the latest versions check the URLs inside the repository.xml.

If you manually unpack the command line tools, take care of placing them in a subfolder inside your $ANDROID_HOME (e.g. $ANDROID_HOME/cmdline-tools/...).

Your CPU supports instructions that this TensorFlow binary was not compiled to use: AVX AVX2

What worked for me tho is this library https://pypi.org/project/silence-tensorflow/

Install this library and do as instructed on the page, it works like a charm!

A component is changing an uncontrolled input of type text to be controlled error in ReactJS

Set Current State first ...this.state

Its because when you are going to assign a new state it may be undefined. so it will be fixed by setting state extracting current state also

this.setState({...this.state, field})

If there is an object in your state, you should set state as follows, suppose you have to set username inside the user object.

this.setState({user:{...this.state.user, ['username']: username}})

How to round a numpy array?

Numpy provides two identical methods to do this. Either use

np.round(data, 2)

or

np.around(data, 2)

as they are equivalent.

See the documentation for more information.

Examples:

>>> import numpy as np
>>> a = np.array([0.015, 0.235, 0.112])
>>> np.round(a, 2)
array([0.02, 0.24, 0.11])
>>> np.around(a, 2)
array([0.02, 0.24, 0.11])
>>> np.round(a, 1)
array([0. , 0.2, 0.1])

How to open local file on Jupyter?

Here's a possibile solution (in Python):

Let's say you have a notebook with a file name, call it Notebook.ipynb. You are currently working in that notebook, and want to access other folders and files around it. Here's it's path:

import os
notebook_path = os.path.abspath("Notebook.ipynb")

In other words, just use the os module, and get the absolute path of your notebook (it's a file, too!). From there, use the os module and your path to navigate.

For example, if your train.csv is in a folder called 'Datasets', and the notebook is sitting right next to that folder, you could get the data like this:

train_csv = os.path.join(os.path.dirname(notebook_path), "Datasets/train.csv")
with open(train_csv) as file:
    #....etc

The takeaway is that the notebook has a file name, and as long as your language supports pathname manipulations (e.g. the os module in Python) you can likely use the notebook filename.

Lastly, the reason your code fails is probably because you're either trying to access local files (like your Mac's 'Downloads' folder) when you're working in an online Notebook (like Kaggle, which hosts your environment for you, online and away from your Mac), or you moved or deleted something in that path. This is what the os module in Python is meant to do; it will find the file's path whether it's on your Mac or in a Kaggle server.

How to convert column with string type to int form in pyspark data frame?

Another way to do it is using the StructField if you have multiple fields that needs to be modified.

Ex:

from pyspark.sql.types import StructField,IntegerType, StructType,StringType
newDF=[StructField('CLICK_FLG',IntegerType(),True),
       StructField('OPEN_FLG',IntegerType(),True),
       StructField('I1_GNDR_CODE',StringType(),True),
       StructField('TRW_INCOME_CD_V4',StringType(),True),
       StructField('ASIAN_CD',IntegerType(),True),
       StructField('I1_INDIV_HHLD_STATUS_CODE',IntegerType(),True)
       ]
finalStruct=StructType(fields=newDF)
df=spark.read.csv('ctor.csv',schema=finalStruct)

Output:

Before

root
 |-- CLICK_FLG: string (nullable = true)
 |-- OPEN_FLG: string (nullable = true)
 |-- I1_GNDR_CODE: string (nullable = true)
 |-- TRW_INCOME_CD_V4: string (nullable = true)
 |-- ASIAN_CD: integer (nullable = true)
 |-- I1_INDIV_HHLD_STATUS_CODE: string (nullable = true)

After:

root
 |-- CLICK_FLG: integer (nullable = true)
 |-- OPEN_FLG: integer (nullable = true)
 |-- I1_GNDR_CODE: string (nullable = true)
 |-- TRW_INCOME_CD_V4: string (nullable = true)
 |-- ASIAN_CD: integer (nullable = true)
 |-- I1_INDIV_HHLD_STATUS_CODE: integer (nullable = true)

This is slightly a long procedure to cast , but the advantage is that all the required fields can be done.

It is to be noted that if only the required fields are assigned the data type, then the resultant dataframe will contain only those fields which are changed.

How to solve npm install throwing fsevents warning on non-MAC OS?

I got the same error. In my case, I was using a mapped drive to edit code off of a second computer, that computer was running linux. Not sure exactly why gulp-watch relies on operating system compatibility prior to install (I would assume it has to do with security purposes). Essentially the error is checking against your operating system and the operating system calling the node module, in my case the two operating systems were not the same so it threw it error. Which from the looks of your error is the same as mine.

The Error

Unsupported platform for [email protected]: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})

How I fixed it?

I logged into the linux computer directly and ran 

npm install --save-dev <module-name>

Then went back into my coding environment and everything was fine after that.

Hope that helps!

Firestore Getting documents id from collection

For angular 8 and Firebase 6 you can use the option id field 

      getAllDocs() {
           const ref = this.db.collection('items');
           return ref.valueChanges({idField: 'customIdName'});
      }

this adds the Id of the document on the object with a specified key (customIdName)

Angular: Cannot Get /

For me it also was problem with path, but I had percentage sign in the root folder.

After I replaced %20 with space, it started to work :)

Styling mat-select in Angular Material

Put your class name on the mat-form-field element. This works for all inputs.

mat-form-field must contain a MatFormFieldControl

Problem 1: MatInputModule Not imported

import MatInputModule and MatFormFieldModule inside module i.e. app.module.ts

import { MatInputModule } from '@angular/material/input';
import { MatFormFieldModule } from "@angular/material/form-field";

Problem 2: Spellings Mistake

Be sure to add matInput and it is case-sensitive.

<input matInput type="text" />

Problem 3: Still compiler giving ERROR

if angular compiler still giving error after fixing above given problems then you must try with restarting the app.

ng serve

The difference between "require(x)" and "import x"

Let me give an example for Including express module with require & import

-require

var express = require('express');

-import

import * as  express from 'express';

So after using any of the above statement we will have a variable called as 'express' with us. Now we can define 'app' variable as,

var app = express();

So we use 'require' with 'CommonJS' and 'import' with 'ES6'.

For more info on 'require' & 'import', read through below links.

require - Requiring modules in Node.js: Everything you need to know

import - An Update on ES6 Modules in Node.js

Is it safe to clean docker/overlay2/

DON'T DO THIS IN PRODUCTION

The answer given by @ravi-luthra technically works but it has some issues!

In my case, I was just trying to recover disk space. The lib/docker/overlay folder was taking 30GB of space and I only run a few containers regularly. Looks like docker has some issue with data leakage and some of the temporary data are not cleared when the container stops.

So I went ahead and deleted all the contents of lib/docker/overlay folder. After that, My docker instance became un-useable. When I tried to run or build any container, It gave me this error:

failed to create rwlayer: symlink ../04578d9f8e428b693174c6eb9a80111c907724cc22129761ce14a4c8cb4f1d7c/diff /var/lib/docker/overlay2/l/C3F33OLORAASNIYB3ZDATH2HJ7: no such file or directory

Then with some trial and error, I solved this issue by running

(WARNING: This will delete all your data inside docker volumes)

docker system prune --volumes -a

So It is not recommended to do such dirty clean ups unless you completely understand how the system works.

How to sign in kubernetes dashboard?

TL;DR

To get the token in a single oneliner:

kubectl -n kube-system describe secret $(kubectl -n kube-system get secret | awk '/^deployment-controller-token-/{print $1}') | awk '$1=="token:"{print $2}'

This assumes that your ~/.kube/config is present and valid. And also that kubectl config get-contexts indicates that you are using the correct context (cluster and namespace) for the dashboard you are logging into.

Explanation

I derived this answer from what I learned from @silverfox's answer. That is a very informative write up. Unfortunately it falls short of telling you how to actually put the information into practice. Maybe I've been doing DevOps too long, but I think in shell. It's much more difficult for me to learn or teach in English.

Here is that oneliner with line breaks and indents for readability:

kubectl -n kube-system describe secret $(
  kubectl -n kube-system get secret | \
  awk '/^deployment-controller-token-/{print $1}'
) | \
awk '$1=="token:"{print $2}'

There are 4 distinct commands and they get called in this order:

  • Line 2 - This is the first command from @silverfox's Token section.
  • Line 3 - Print only the first field of the line beginning with deployment-controller-token- (which is the pod name)
  • Line 1 - This is the second command from @silverfox's Token section.
  • Line 5 - Print only the second field of the line whose first field is "token:"

Tensorflow import error: No module named 'tensorflow'

Since none of the above solve my issue, I will post my solution

WARNING: if you just installed TensorFlow using conda, you have to restart your command prompt!

Solution: restart terminal ENTIRELY and restart conda environment

Select all occurrences of selected word in VSCode

Ctrl + F2 works for me in Windows 10.

Ctrl + Shift + L starts performance logging

React - clearing an input value after form submit

this.mainInput doesn't actually point to anything. Since you are using a controlled component (i.e. the value of the input is obtained from state) you can set this.state.city to null:

onHandleSubmit(e) {
  e.preventDefault();
  const city = this.state.city;
  this.props.onSearchTermChange(city);
  this.setState({ city: '' });
}

LabelEncoder: TypeError: '>' not supported between instances of 'float' and 'str'

As string data types have variable length, it is by default stored as object type. I faced this problem after treating missing values too. Converting all those columns to type 'category' before label encoding worked in my case.

df[cat]=df[cat].astype('category')

And then check df.dtypes and perform label encoding.

intellij idea - Error: java: invalid source release 1.9

When using maven project.

check pom.xml file

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>9</java.version>
</properties>

if you have jdk 8 installed in your machine, change java.version property from 9 to 8

Unable to merge dex

I had the same problem when I update from com.google.android.gms:play-services:11.2.2 to com.google.android.gms:play-services:11.4.0. This solved it for me:

  1. clean
  2. rebuild

ImportError: Couldn't import Django

I faced the same issue, and in my case it was because I had multiple python versions on my machine, in addition to the Anaconda ones. In my case django didn't worked well with my anaconda python. I knew that when I run import django on each python terminal for all versions I have.

As a summary here are the steps I made to get this solved:

  1. Run the CMD as Admin

  2. Create a project folder.

  3. Create a new ENV for this new project INSIDE THE PROJECT Folder...

    pip install virtualenv >> virtualenv new_env`

  4. Activate it: 

    .\new_env\Scripts\activate`

  5. After the env activation ? Install Django: 

    python -m pip install Django

The python version you used here in step 5 will determine which python will to work with this installed Django.

Detect if the device is iPhone X

SWIFT 4+ Answer

iPhone X, XR, XS, XSMAX, 11 Pro, 11 Pro Max:

Note: Need real device for test

Reference

 let deviceType = UIDevice.current.modelName
        switch deviceType {
        case "iPhone10,3", "iPhone10,6":
            print("iPhoneX")
        case "iPhone11,2":
            print("iPhone XS")
        case "iPhone11,4":
            print("iPhone XS Max")
        case "iPhone11,6":
            print("iPhone XS Max China")
        case "iPhone11,8":
            print("iPhone XR")
        case "iPhone12,3":
            print("iPhone 11 Pro")
        case "iPhone12,5":
            print("iPhone 11 Pro Max")
        default:
            break
}

extension UIDevice {
    var modelName: String {
        var systemInfo = utsname()
        uname(&systemInfo)
        let machineMirror = Mirror(reflecting: systemInfo.machine)
        let identifier = machineMirror.children.reduce("") { identifier, element in
            guard let value = element.value as? Int8, value != 0 else { return identifier }
            return identifier + String(UnicodeScalar(UInt8(value)))
        }
        return identifier
    }
}

How to use log4net in Asp.net core 2.0

Following on Irfan's answer, I have the following XML configuration on OSX with .NET Core 2.1.300 which correctly logs and appends to a ./log folder and also to the console. Note the log4net.config must exist in the solution root (whereas in my case, my app root is a subfolder).

<?xml version="1.0" encoding="utf-8" ?>
<log4net>
  <appender name="ConsoleAppender" type="log4net.Appender.ConsoleAppender" >
      <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date %-5level %logger - %message%newline" />
      </layout>
  </appender>
  <appender name="RollingLogFileAppender" type="log4net.Appender.RollingFileAppender">
    <lockingModel type="log4net.Appender.FileAppender+MinimalLock"/>
    <file value="logs/" />
    <datePattern value="yyyy-MM-dd.'txt'"/>
    <staticLogFileName value="false"/>
    <appendToFile value="true"/>
    <rollingStyle value="Date"/>
    <maxSizeRollBackups value="100"/>
    <maximumFileSize value="15MB"/>
    <layout type="log4net.Layout.PatternLayout">
      <conversionPattern value="%date [%thread] %-5level App  %newline %message %newline %newline"/>
    </layout>
  </appender>
    <root>
      <level value="ALL"/>
      <appender-ref ref="RollingLogFileAppender"/>
      <appender-ref ref="ConsoleAppender"/>
    </root>
</log4net>

Another note, the traditional way of setting the XML up within app.config did not work:

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <configSections>
    <section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler, log4net" />
  </configSections>
  <log4net> ...

For some reason, the log4net node was not found when accessing the XMLDocument via log4netConfig["log4net"].

Vuex - Computed property "name" was assigned to but it has no setter

It should be like this.

In your Component

computed: {
        ...mapGetters({
                nameFromStore: 'name'
            }),
        name: {
           get(){
             return this.nameFromStore
           },
           set(newName){
             return newName
           } 
        }
    }

In your store

export const store = new Vuex.Store({
         state:{
             name : "Stackoverflow"
         },
         getters: {
                 name: (state) => {
                     return state.name;
                 }
         }
}

No converter found capable of converting from type to type

Return ABDeadlineType from repository:

public interface ABDeadlineTypeRepository extends JpaRepository<ABDeadlineType, Long> {
    List<ABDeadlineType> findAllSummarizedBy();
}

and then convert to DeadlineType. Manually or use mapstruct.

Or call constructor from @Query annotation:

public interface DeadlineTypeRepository extends JpaRepository<ABDeadlineType, Long> {

    @Query("select new package.DeadlineType(a.id, a.code) from ABDeadlineType a ")
    List<DeadlineType> findAllSummarizedBy();
}

Or use @Projection:

@Projection(name = "deadline", types = { ABDeadlineType.class })
public interface DeadlineType {

    @Value("#{target.id}")
    String getId();

    @Value("#{target.code}")
    String getText();

}

Update: Spring can work without @Projection annotation:

public interface DeadlineType {
    String getId();    
    String getText();
}

npm WARN ... requires a peer of ... but none is installed. You must install peer dependencies yourself

Had the same issue installing angular material CDK:

npm install --save @angular/material @angular/cdk @angular/animations

Adding -dev like below worked for me:

npm install --save-dev @angular/material @angular/cdk @angular/animations

Property 'json' does not exist on type 'Object'

For future visitors: In the new HttpClient (Angular 4.3+), the response object is JSON by default, so you don't need to do response.json().data anymore. Just use response directly.

Example (modified from the official documentation):

import { HttpClient } from '@angular/common/http';

@Component(...)
export class YourComponent implements OnInit {

  // Inject HttpClient into your component or service.
  constructor(private http: HttpClient) {}

  ngOnInit(): void {
    this.http.get('https://api.github.com/users')
        .subscribe(response => console.log(response));
  }
}

Don't forget to import it and include the module under imports in your project's app.module.ts:

...
import { HttpClientModule } from '@angular/common/http';

@NgModule({
  imports: [
    BrowserModule,
    // Include it under 'imports' in your application module after BrowserModule.
    HttpClientModule,
    ...
  ],
  ...

How to create Toast in Flutter?

to show toast message you can use flutterToast plugin to use this plugin you have to

  1. Add this dependency to your pubspec.yaml file :- fluttertoast: ^3.1.0
  2. to get the package you have to run this command :- $ flutter packages get
  3. import the package :- import 'package:fluttertoast/fluttertoast.dart';

use it like this

Fluttertoast.showToast(
        msg: "your message",
        toastLength: Toast.LENGTH_SHORT,
        gravity: ToastGravity.BOTTOM // also possible "TOP" and "CENTER"
        backgroundColor: "#e74c3c",
        textColor: '#ffffff');

For more info check this

npm ERR! code UNABLE_TO_GET_ISSUER_CERT_LOCALLY

Trust me, this will work for you: 

    npm config set registry http://registry.npmjs.org/

JSON parse error: Can not construct instance of java.time.LocalDate: no String-argument constructor/factory method to deserialize from String value

Spring Boot 2.2.2 / Gradle:

Gradle (build.gradle):

implementation("com.fasterxml.jackson.datatype:jackson-datatype-jsr310")

Entity (User.class):

LocalDate dateOfBirth;

Code:

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JavaTimeModule());
User user = mapper.readValue(json, User.class);

Node.js: Python not found exception due to node-sass and node-gyp

I found the same issue with Node 12.19.0 and yarn 1.22.5 on Windows 10. I fixed the problem by installing latest stable python 64-bit with adding the path to Environment Variables during python installation. After python installation, I restarted my machine for env vars.

Get ConnectionString from appsettings.json instead of being hardcoded in .NET Core 2.0 App

STEP 1: Include the following in OnConfiguring()

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        IConfigurationRoot configuration = new ConfigurationBuilder()
            .SetBasePath(AppDomain.CurrentDomain.BaseDirectory)
            .AddJsonFile("appsettings.json")
            .Build();
        optionsBuilder.UseSqlServer(configuration.GetConnectionString("DefaultConnection"));
    }

STEP 2: Create appsettings.json: 

  {
    "ConnectionStrings": {       
      "DefaultConnection": "Server=YOURSERVERNAME; Database=YOURDATABASENAME; Trusted_Connection=True; MultipleActiveResultSets=true"        
    } 
  }

STEP 3: Hard copy appsettings.json to the correct directory 

  Hard copy appsettings.json.config to the directory specified in the AppDomain.CurrentDomain.BaseDirectory directory. 
  Use your debugger to find out which directory that is.

Assumption: you have already included package Microsoft.Extensions.Configuration.Json (get it from Nuget) in your project.

Update some specific field of an entity in android Room

I think you don't need to update only some specific field. Just update whole data.

@Update query

It is a given query basically. No need to make some new query.

@Dao
interface MemoDao {

    @Insert
    suspend fun insert(memo: Memo)

    @Delete
    suspend fun delete(memo: Memo)

    @Update
    suspend fun update(memo: Memo)
}

Memo.class

@Entity
data class Memo (
    @PrimaryKey(autoGenerate = true) val id: Int,
    @ColumnInfo(name = "title") val title: String?,
    @ColumnInfo(name = "content") val content: String?,
    @ColumnInfo(name = "photo") val photo: List<ByteArray>?
)

Only thing you need to know is 'id'. For instance, if you want to update only 'title', you can reuse 'content' and 'photo' from already inserted data. In real code, use like this

val memo = Memo(id, title, content, byteArrayList)
memoViewModel.update(memo)

Django - Reverse for '' not found. '' is not a valid view function or pattern name

If you dont define name in the path field, usually the error will come. e.g.: path('crud/',ABC.as_view(),name="crud")

How to add a ListView to a Column in Flutter?

Here is a very simple method. There are a different ways to do it, like you can get it by Expanded, Sizedbox or Container and it should be used according to needs.

  1. Use Expanded : A widget that expands a child of a Row, Column, or Flex so that the child fills the available space.

    Expanded(
    child: ListView(scrollDirection: Axis.horizontal,
        children: <Widget>[
          OutlineButton(onPressed: null,
              child: Text("Facebook")),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("Google")),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("Twitter"))
        ]),
  ),

Using an Expanded widget makes a child of a Row, Column, or Flex expand to fill the available space along the main axis (e.g., horizontally for a Row or vertically for a Column).

  1. Use SizedBox : A box with a specified size.

    SizedBox(
    height: 100,
    child: ListView(scrollDirection: Axis.horizontal,
        children: <Widget>[
          OutlineButton(
              color: Colors.white,
              onPressed: null,
              child: Text("Amazon")
          ),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("Instagram")),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("SoundCloud"))
        ]),
 ),

If given a child, this widget forces its child to have a specific width and/or height (assuming values are permitted by this widget's parent).

  1. Use Container : A convenience widget that combines common painting, positioning, and sizing widgets.

     Container(
    height: 80.0,
    child: ListView(scrollDirection: Axis.horizontal,
        children: <Widget>[
          OutlineButton(onPressed: null,
              child: Text("Shopify")),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("Yahoo")),
          Padding(padding: EdgeInsets.all(5.00)),
          OutlineButton(onPressed: null,
              child: Text("LinkedIn"))
        ]),
  ),

The output to all three would be something like this

enter image description here

bootstrap 4 responsive utilities visible / hidden xs sm lg not working

Screen Size Class

-

  1. Hidden on all .d-none

  2. Hidden only on xs .d-none .d-sm-block

  3. Hidden only on sm .d-sm-none .d-md-block

  4. Hidden only on md .d-md-none .d-lg-block

  5. Hidden only on lg .d-lg-none .d-xl-block

  6. Hidden only on xl .d-xl-none

  7. Visible on all .d-block

  8. Visible only on xs .d-block .d-sm-none

  9. Visible only on sm .d-none .d-sm-block .d-md-none

  10. Visible only on md .d-none .d-md-block .d-lg-none

  11. Visible only on lg .d-none .d-lg-block .d-xl-none

  12. Visible only on xl .d-none .d-xl-block

Refer this link http://getbootstrap.com/docs/4.0/utilities/display/#hiding-elements

4.5 link: https://getbootstrap.com/docs/4.5/utilities/display/#hiding-elements

bootstrap.min.js:6 Uncaught Error: Bootstrap dropdown require Popper.js

You need to install popperjs along with bootstrap to get rid of this error.Note that if you are using "bootstrap": "^4.4.1", and @popperjs/core v2.x combinations,bootstrap may not support popperjs version. So downgrade your version.

Option 1: npm install popper.js@^1.12.9 --save

and Add following script between jquery and bootstrap scripts.

"node_modules/popper.js/dist/umd/popper.min.js",

Option 2: Add following script tag to index.html

<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js" integrity="sha384-b/U6ypiBEHpOf/4+1nzFpr53nxSS+GLCkfwBdFNTxtclqqenISfwAzpKaMNFNmj4" crossorigin="anonymous"></script

How to prevent page from reloading after form submit - JQuery

The <button> element, when placed in a form, will submit the form automatically unless otherwise specified. You can use the following 2 strategies:

  1. Use <button type="button"> to override default submission behavior
  2. Use event.preventDefault() in the onSubmit event to prevent form submission

Solution 1:

  • Advantage: simple change to markup
  • Disadvantage: subverts default form behavior, especially when JS is disabled. What if the user wants to hit "enter" to submit?

Insert extra type attribute to your button markup:

<button id="button" type="button" value="send" class="btn btn-primary">Submit</button>

Solution 2:

  • Advantage: form will work even when JS is disabled, and respects standard form UI/UX such that at least one button is used for submission

Prevent default form submission when button is clicked. Note that this is not the ideal solution because you should be in fact listening to the submit event, not the button click event:

$(document).ready(function () {
  // Listen to click event on the submit button
  $('#button').click(function (e) {

    e.preventDefault();

    var name = $("#name").val();
    var email = $("#email").val();

    $.post("process.php", {
      name: name,
      email: email
    }).complete(function() {
        console.log("Success");
      });
  });
});

Better variant:

In this improvement, we listen to the submit event emitted from the <form> element:

$(document).ready(function () {
  // Listen to submit event on the <form> itself!
  $('#main').submit(function (e) {

    e.preventDefault();

    var name = $("#name").val();
    var email = $("#email").val();

    $.post("process.php", {
      name: name,
      email: email
    }).complete(function() {
        console.log("Success");
      });
  });
});

Even better variant: use .serialize() to serialize your form, but remember to add name attributes to your input:

The name attribute is required for .serialize() to work, as per jQuery's documentation:

For a form element's value to be included in the serialized string, the element must have a name attribute.

<input type="text" id="name" name="name" class="form-control mb-2 mr-sm-2 mb-sm-0" id="inlineFormInput" placeholder="Jane Doe">
<input type="text" id="email" name="email" class="form-control" id="inlineFormInputGroup" placeholder="[email protected]">

And then in your JS:

$(document).ready(function () {
  // Listen to submit event on the <form> itself!
  $('#main').submit(function (e) {

    // Prevent form submission which refreshes page
    e.preventDefault();

    // Serialize data
    var formData = $(this).serialize();

    // Make AJAX request
    $.post("process.php", formData).complete(function() {
      console.log("Success");
    });
  });
});

Where to find htdocs in XAMPP Mac

for each easy and useful access you can add terminal command via editing your bash profile, here how:

open terminal -> type cd hit enter. then type nano .bash_profile then add this line alias htdocs="cd ~/.bitnami/stackman/machines/xampp/volumes/root/htdocs" Now hit ctrl + o then hit enter, then hit ctrl + x Now to refresh the terminal commands type the following command

source .bash_profile

Now you can use htdocs command each time you want to navigate htdocs folder.

Min and max value of input in angular4 application

Simply do this in angular2+ by adding (onkeypress)

<input type="number" 
    maxlength="3" 
    min="0" 
    max="100" 
    required 
    mdInput 
    placeholder="Charge" 
    [(ngModel)]="rateInput"
    (onkeypress)="return (event.charCode == 8 || event.charCode == 0) ? null : event.charCode >= 48 && event.charCode <= 57"
    name="rateInput">

Tested on Angular 7

Angular 4 HttpClient Query Parameters

With Angular 7, I got it working by using the following without using HttpParams. 

import { HttpClient } from '@angular/common/http';

export class ApiClass {

  constructor(private httpClient: HttpClient) {
    // use it like this in other services / components etc.
    this.getDataFromServer().
      then(res => {
        console.log('res: ', res);
      });
  }

  getDataFromServer() {
    const params = {
      param1: value1,
      param2: value2
    }
    const url = 'https://api.example.com/list'

    // { params: params } is the same as { params } 
    // look for es6 object literal to read more
    return this.httpClient.get(url, { params }).toPromise();
  }
}

Count the Number of Tables in a SQL Server Database

 
USE MyDatabase
SELECT Count(*)
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_TYPE = 'BASE TABLE';

to get table counts 

SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = 'dbName';

this also works

USE databasename;
SHOW TABLES;
SELECT FOUND_ROWS();

Update .NET web service to use TLS 1.2

PowerBI Embedded requires TLS 1.2.

The answer above by Etienne Faucher is your solution. quick link to above answer... quick link to above answer... ( https://stackoverflow.com/a/45442874 )

PowerBI Requires TLS 1.2 June 2020 - This Is your Answer - Consider Forcing your IIS runtime to get up to 4.6 to force the default TLS 1.2 behavior you are looking for from the framework. The above answer gives you a config change only solution.

Symptoms: Forced Closed Rejected TCP/IP Connection to Microsoft PowerBI Embedded that just shows up all of a sudden across your systems.

These PowerBI Calls just stop working with a Hard TCP/IP Close error like a firewall would block a connection. Usually the auth steps work - it is when you hit the service for specific workspace and report id's that it fails.

This is the 2020 note from Microsoft PowerBI about TLS 1.2 required

PowerBIClient

methods that show this problem

GetReportsInGroupAsync GetReportsInGroupAsAdminAsync GetReportsAsync GetReportsAsAdminAsync Microsoft.PowerBI.Api HttpClientHandler Force TLS 1.1 TLS 1.2

Search Error Terms to help people find this: System.Net.Http.HttpRequestException: An error occurred while sending the request System.Net.WebException: The underlying connection was closed: An unexpected error occurred on a send. System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host.

ProgressDialog is deprecated.What is the alternate one to use?

Yes, ProgressDialog is deprecated but Dialog isn't.

You can inflate your own XML file ( containing a progress bar and a loading text) into your dialog object and then display or hide it using the show() and dismiss() functions. Here is an example (Kotlin):

ProgressDialog class:

class ProgressDialog {
companion object {
    fun progressDialog(context: Context): Dialog{
        val dialog = Dialog(context)
        val inflate = LayoutInflater.from(context).inflate(R.layout.progress_dialog, null)
        dialog.setContentView(inflate)
        dialog.setCancelable(false)
        dialog.window!!.setBackgroundDrawable(
                ColorDrawable(Color.TRANSPARENT))
        return dialog
    }
  }
}

XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
android:background="#fff"
android:padding="13dp"
android:layout_height="wrap_content">
<ProgressBar
    android:id="@+id/progressBar"
    style="?android:attr/progressBarStyle"
    android:layout_width="100dp"
    android:layout_margin="7dp"
    android:layout_height="100dp"/>
<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerVertical="true"
    android:layout_margin="7dp"
    android:layout_toEndOf="@+id/progressBar"
    android:text="Loading..." />
</RelativeLayout>

In your code: Just do var dialog = ProgressDialog.progressDialog(context)

To show: dialog.show()

To hide: dialog.dismiss()

Fixed digits after decimal with f-strings

Adding to Rob's answer, you can use format specifiers with f strings (more here).

  • You can control the number of decimals:
pi = 3.141592653589793238462643383279

print(f'The first 6 decimals of pi are {pi:.6f}.')

The first 6 decimals of pi are 3.141593.
  • You can convert to percentage:
grade = 29/45

print(f'My grade rounded to 3 decimals is {grade:.3%}.')

My grade rounded to 3 decimals is 64.444%.
  • You can do other things like print constant length:
from random import randint
for i in range(5):
    print(f'My money is {randint(0, 150):>3}$')

My money is 126$
My money is   7$
My money is 136$
My money is  15$
My money is  88$
  • Or even print with a comma thousand separator:
print(f'I am worth {10000000000:,}$')

I am worth 10,000,000,000$

Reset input value in angular 2

If you want to clear the input by using the HTML ONLY, then you can do something like this:

<input type="text"
       (keyup)="0"
       #searchCollectorInput
       class="search-metrics"
       placeholder="Find">

Notice the importance of (keyup)=0 and the reference to the input of course.

Then reset it like this:

<span *ngIf="searchCollectorInput.value.length > 0"
      (click)="searchCollectorInput.value = ''"
      class="fa fa-close" ></span>

Get current url in Angular

With pure JavaScript:

console.log(window.location.href)

Using Angular:

this.router.url

import { Component } from '@angular/core';
import { Router } from '@angular/router';

@Component({
    template: 'The href is: {{href}}'
    /*
    Other component settings
    */
})
export class Component {
    public href: string = "";

    constructor(private router: Router) {}

    ngOnInit() {
        this.href = this.router.url;
        console.log(this.router.url);
    }
}

The plunkr is here: https://plnkr.co/edit/0x3pCOKwFjAGRxC4hZMy?p=preview

No String-argument constructor/factory method to deserialize from String value ('')

I found a different way to handle this error. (the variables is according to the original question) 

   JsonNode parsedNodes = mapper.readValue(jsonMessage , JsonNode.class);
        Response response = xmlMapper.enable(ACCEPT_EMPTY_STRING_AS_NULL_OBJECT,ACCEPT_SINGLE_VALUE_AS_ARRAY )
                .disable(FAIL_ON_UNKNOWN_PROPERTIES, FAIL_ON_IGNORED_PROPERTIES)
                .convertValue(parsedNodes, Response.class);

Specifying onClick event type with Typescript and React.Konva

Taken from the ReactKonvaCore.d.ts file:

onClick?(evt: Konva.KonvaEventObject<MouseEvent>): void;

So, I'd say your event type is Konva.KonvaEventObject<MouseEvent>

Uncaught Error: Unexpected module 'FormsModule' declared by the module 'AppModule'. Please add a @Pipe/@Directive/@Component annotation

FormsModule should be added at imports array not declarations array.

  • imports array is for importing modules such as BrowserModule, FormsModule, HttpModule
  • declarations array is for your Components, Pipes, Directives

refer below change:

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    FormsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})

If condition inside of map() React

You are using both ternary operator and if condition, use any one.

By ternary operator:

.map(id => {
    return this.props.schema.collectionName.length < 0 ?
        <Expandable>
            <ObjectDisplay
                key={id}
                parentDocumentId={id}
                schema={schema[this.props.schema.collectionName]}
                value={this.props.collection.documents[id]}
            />
        </Expandable>
    :
        <h1>hejsan</h1>
}

By if condition:

.map(id => {
    if(this.props.schema.collectionName.length < 0)
        return <Expandable>
                  <ObjectDisplay
                      key={id}
                      parentDocumentId={id}
                      schema={schema[this.props.schema.collectionName]}
                      value={this.props.collection.documents[id]}
                  />
              </Expandable>
    return <h1>hejsan</h1>
}

iOS 11, 12, and 13 installed certificates not trusted automatically (self signed)

If you are not seeing the certificate under General->About->Certificate Trust Settings, then you probably do not have the ROOT CA installed. Very important -- needs to be a ROOT CA, not an intermediary CA.

I just answered a question here explaining how to obtain the ROOT CA and get things to show up: How to install self-signed certificates in iOS 11

Pip error: Microsoft Visual C++ 14.0 is required

If you already have Visual Studio Build Tools installed but you're still getting that error, then you may need to "Modify" your installation to include the Visual C++ build tools.

To do that:

  1. Open up the Visual Studio Installer (you can search for it in the Start Menu if needed).

  2. Find Visual Studio Build Tools and click "Modify":

enter image description here

  1. Add a checkmark to Visual C++ build tools and then click "Modify" in the bottom right to install them:

enter image description here

After the C++ tools finish installing, run the pip command again and it should work.

Python TypeError must be str not int

you need to cast int to str before concatenating. for that use str(temperature). Or you can print the same output using , if you don't want to convert like this.

print("the furnace is now",temperature , "degrees!")

Visual Studio Code - Target of URI doesn't exist 'package:flutter/material.dart'

Add dependencies. for example:- import 'package:audioplayers/audio_cache.dart'; in the above package if we only use this package then it shows error but if we add dependencies in pubspec.yaml such as 

dependencies:
    flutter:
      sdk: flutter
    cupertino_icons: ^0.1.2
    audioplayers: ^0.14.1

enter image description here

then click on packages get.

as you see this, I can also insert dependencies so if you insert dependencies along with your package then you are good to go.

(change) vs (ngModelChange) in angular

In Angular 7, the (ngModelChange)="eventHandler()" will fire before the value bound to [(ngModel)]="value" is changed while the (change)="eventHandler()" will fire after the value bound to [(ngModel)]="value" is changed.

How to add empty spaces into MD markdown readme on GitHub?

Instead of using HTML entities like &nbsp; and &emsp; (as others have suggested), you can use the Unicode em space (8195 in UTF-8) directly. Try copy-pasting the following into your README.md. The spaces at the start of the lines are em spaces.

The action of every agent <br />
  into the world <br />
starts <br />
  from their physical selves. <br />

Jest spyOn function called

You're almost there. Although I agree with @Alex Young answer about using props for that, you simply need a reference to the instance before trying to spy on the method.

describe('my sweet test', () => {
 it('clicks it', () => {
    const app = shallow(<App />)
    const instance = app.instance()
    const spy = jest.spyOn(instance, 'myClickFunc')

    instance.forceUpdate();    

    const p = app.find('.App-intro')
    p.simulate('click')
    expect(spy).toHaveBeenCalled()
 })
})

Docs: http://airbnb.io/enzyme/docs/api/ShallowWrapper/instance.html

Kubernetes Pod fails with CrashLoopBackOff

The issue caused by the docker container which exits as soon as the "start" process finishes. i added a command that runs forever and it worked. This issue mentioned here

TypeError: Object of type 'bytes' is not JSON serializable

You are creating those bytes objects yourself:

item['title'] = [t.encode('utf-8') for t in title]
item['link'] = [l.encode('utf-8') for l in link]
item['desc'] = [d.encode('utf-8') for d in desc]
items.append(item)

Each of those t.encode(), l.encode() and d.encode() calls creates a bytes string. Do not do this, leave it to the JSON format to serialise these.

Next, you are making several other errors; you are encoding too much where there is no need to. Leave it to the json module and the standard file object returned by the open() call to handle encoding.

You also don't need to convert your items list to a dictionary; it'll already be an object that can be JSON encoded directly:

class W3SchoolPipeline(object):    
    def __init__(self):
        self.file = open('w3school_data_utf8.json', 'w', encoding='utf-8')

    def process_item(self, item, spider):
        line = json.dumps(item) + '\n'
        self.file.write(line)
        return item

I'm guessing you followed a tutorial that assumed Python 2, you are using Python 3 instead. I strongly suggest you find a different tutorial; not only is it written for an outdated version of Python, if it is advocating line.decode('unicode_escape') it is teaching some extremely bad habits that'll lead to hard-to-track bugs. I can recommend you look at Think Python, 2nd edition for a good, free, book on learning Python 3.

Vue component event after render

updated() should be what you're looking for:

Called after a data change causes the virtual DOM to be re-rendered and patched.

The component’s DOM will have been updated when this hook is called, so you can perform DOM-dependent operations here.

How to run shell script file using nodejs?

Also, you can use shelljs plugin. It's easy and it's cross-platform.

Install command:

npm install [-g] shelljs

What is shellJS

ShellJS is a portable (Windows/Linux/OS X) implementation of Unix shell commands on top of the Node.js API. You can use it to eliminate your shell script's dependency on Unix while still keeping its familiar and powerful commands. You can also install it globally so you can run it from outside Node projects - say goodbye to those gnarly Bash scripts!

An example of how it works:

var shell = require('shelljs');

if (!shell.which('git')) {
  shell.echo('Sorry, this script requires git');
  shell.exit(1);
}

// Copy files to release dir
shell.rm('-rf', 'out/Release');
shell.cp('-R', 'stuff/', 'out/Release');

// Replace macros in each .js file
shell.cd('lib');
shell.ls('*.js').forEach(function (file) {
  shell.sed('-i', 'BUILD_VERSION', 'v0.1.2', file);
  shell.sed('-i', /^.*REMOVE_THIS_LINE.*$/, '', file);
  shell.sed('-i', /.*REPLACE_LINE_WITH_MACRO.*\n/, shell.cat('macro.js'), file);
});
shell.cd('..');

// Run external tool synchronously
if (shell.exec('git commit -am "Auto-commit"').code !== 0) {
  shell.echo('Error: Git commit failed');
  shell.exit(1);
}

Also, you can use from the command line:

$ shx mkdir -p foo
$ shx touch foo/bar.txt
$ shx rm -rf foo

AngularJS. How to call controller function from outside of controller component

Call Angular Scope function from outside the controller.

// Simply Use "Body" tag, Don't try/confuse using id/class.

var scope = angular.element('body').scope();             
scope.$apply(function () {scope.YourAngularJSFunction()});

node.js shell command execution

There's a variable conflict in your run_cmd function:

  var me = this;
  child.stdout.on('data', function(me, data) {
    // me is overriden by function argument
    cb(me, data);
  });

Simply change it to this:

  var me = this;
  child.stdout.on('data', function(data) {
    // One argument only!
    cb(me, data);
  });

In order to see errors always add this:

  child.stderr.on('data', function(data) {
      console.log( data );
  });

EDIT You're code fails because you are trying to run dir which is not provided as a separate standalone program. It is a command in cmd process. If you want to play with filesystem use native require( 'fs' ).

Alternatively ( which I do not recommend ) you can create a batch file which you can then run. Note that OS by default fires batch files via cmd.

Error: could not find function ... in R

Another problem, in the presence of a NAMESPACE, is that you are trying to run an unexported function from package foo.

For example (contrived, I know, but):

> mod <- prcomp(USArrests, scale = TRUE)
> plot.prcomp(mod)
Error: could not find function "plot.prcomp"

Firstly, you shouldn't be calling S3 methods directly, but lets assume plot.prcomp was actually some useful internal function in package foo. To call such function if you know what you are doing requires the use of :::. You also need to know the namespace in which the function is found. Using getAnywhere() we find that the function is in package stats:

> getAnywhere(plot.prcomp)
A single object matching ‘plot.prcomp’ was found
It was found in the following places
  registered S3 method for plot from namespace stats
  namespace:stats
with value

function (x, main = deparse(substitute(x)), ...) 
screeplot.default(x, main = main, ...)
<environment: namespace:stats>

So we can now call it directly using:

> stats:::plot.prcomp(mod)

I've used plot.prcomp just as an example to illustrate the purpose. In normal use you shouldn't be calling S3 methods like this. But as I said, if the function you want to call exists (it might be a hidden utility function for example), but is in a namespace, R will report that it can't find the function unless you tell it which namespace to look in.

Compare this to the following: stats::plot.prcomp The above fails because while stats uses plot.prcomp, it is not exported from stats as the error rightly tells us:

Error: 'plot.prcomp' is not an exported object from 'namespace:stats'

This is documented as follows:

pkg::name returns the value of the exported variable name in namespace pkg, whereas pkg:::name returns the value of the internal variable name.

print arraylist element?

Do you want to print the entire list or you want to iterate through each element of the list? Either way to print anything meaningful your Dog class need to override the toString() method (as mentioned in other answers) from the Object class to return a valid result. 

public class Print {
    public static void main(final String[] args) {
        List<Dog> list = new ArrayList<Dog>();
        Dog e = new Dog("Tommy");
        list.add(e);
        list.add(new Dog("tiger"));
        System.out.println(list);
        for(Dog d:list) {
            System.out.println(d);
            // prints [Tommy, tiger]
        }
    }

    private static class Dog {
        private final String name;
        public Dog(final String name) {
            this.name = name;
        }

        @Override
        public String toString() {
            return name;
        }
    }
}

The output of this code is:

[Tommy, tiger]  
Tommy  
tiger

Use Ant for running program with command line arguments

Extending Richard Cook's answer.

Here's the ant task to run any program (including, but not limited to Java programs):

<target name="run">
   <exec executable="name-of-executable">
      <arg value="${arg0}"/>
      <arg value="${arg1}"/>
   </exec>
</target>

Here's the task to run a Java program from a .jar file:

<target name="run-java">
   <java jar="path for jar">
      <arg value="${arg0}"/>
      <arg value="${arg1}"/>
   </java>
</target>

You can invoke either from the command line like this:

ant -Darg0=Hello -Darg1=World run

Make sure to use the -Darg syntax; if you ran this:

ant run arg0 arg1

then ant would try to run targets arg0 and arg1.

Graphical HTTP client for windows

https://play.google.com/store/apps/details?id=com.snmba.restclient

works from Android Tablets & Phones. Flexible enough to try various combinations.

Static nested class in Java, why?

static nested class is just like any other outer class, as it doesn't have access to outer class members.

Just for packaging convenience we can club static nested classes into one outer class for readability purpose. Other than this there is no other use case of static nested class.

Example for such kind of usage, you can find in Android R.java (resources) file. Res folder of android contains layouts (containing screen designs), drawable folder (containing images used for project), values folder (which contains string constants), etc..

Sine all the folders are part of Res folder, android tool generates a R.java (resources) file which internally contains lot of static nested classes for each of their inner folders.

Here is the look and feel of R.java file generated in android: Here they are using only for packaging convenience. 

/* AUTO-GENERATED FILE.  DO NOT MODIFY.
 *
 * This class was automatically generated by the
 * aapt tool from the resource data it found.  It
 * should not be modified by hand.
 */

package com.techpalle.b17_testthird;

public final class R {
    public static final class drawable {
        public static final int ic_launcher=0x7f020000;
    }
    public static final class layout {
        public static final int activity_main=0x7f030000;
    }
    public static final class menu {
        public static final int main=0x7f070000;
    }
    public static final class string {
        public static final int action_settings=0x7f050001;
        public static final int app_name=0x7f050000;
        public static final int hello_world=0x7f050002;
    }
}

ActiveMQ or RabbitMQ or ZeroMQ or

I wrote about my initial experience regarding AMQP, Qpid and ZeroMQ here: http://ron.shoutboot.com/2010/09/25/is-ampq-for-you/

My subjective opinion is that AMQP is fine if you really need the persistent messaging facilities and is not too concerned that the broker may be a bottleneck. Also, C++ client is currently missing for AMQP (Qpid didn't win my support; not sure about the ActiveMQ client however), but maybe work in progress. ZeroMQ may be the way otherwise.

Is it possible to use the SELECT INTO clause with UNION [ALL]?

 
SELECT * INTO tmpFerdeen FROM 
(SELECT top(100)*  
FROM Customers 
UNION All 
SELECT top(100)*  
FROM CustomerEurope 
UNION All 
SELECT top(100)*  
FROM CustomerAsia 
UNION All 
SELECT top(100)*  
FROM CustomerAmericas) AS Blablabal

This "Blablabal" is necessary

JQuery Number Formatting

http://jquerypriceformat.com/#examples

https://github.com/flaviosilveira/Jquery-Price-Format

html input runing for live chance.

<input type="text" name="v7"  class="priceformat"/>
<input type="text" name="v8"  class="priceformat"/>


$('.priceformat').each(function( index ) {
    $(this).priceFormat({ prefix: '',  thousandsSeparator: '' });
});

//5000.00

//5.000,00

//5,000.00

Changing ImageView source

get ID of ImageView as

ImageView imgFp = (ImageView) findViewById(R.id.imgFp);

then Use 

imgFp.setImageResource(R.drawable.fpscan);

to set source image programatically instead from XML.

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

How can I get zoom functionality for images?

You could also try out http://code.google.com/p/android-multitouch-controller/

The library is really great, although initially a little hard to grasp.

How to fix 'android.os.NetworkOnMainThreadException'?

Do the network actions on another thread

For Example:

new Thread(new Runnable(){
    @Override
    public void run() {
        // Do network action in this function
    }
}).start();

And add this to AndroidManifest.xml 

<uses-permission android:name="android.permission.INTERNET"/>

insert/delete/update trigger in SQL server

I use that for all status (update, insert and delete)

CREATE TRIGGER trg_Insert_Test
ON [dbo].[MyTable]
AFTER UPDATE, INSERT, DELETE 
AS
BEGIN
SET NOCOUNT ON;

DECLARE @Activity  NVARCHAR (50)

-- update
IF EXISTS (SELECT * FROM inserted) AND EXISTS (SELECT * FROM deleted)
BEGIN
    SET @Activity = 'UPDATE'
END

-- insert
IF EXISTS (SELECT * FROM inserted) AND NOT EXISTS(SELECT * FROM deleted)
BEGIN
    SET @Activity = 'INSERT'
END

-- delete
IF EXISTS (SELECT * FROM deleted) AND NOT EXISTS(SELECT * FROM inserted)
BEGIN
    SET @Activity = 'DELETE'
END



-- delete temp table
IF OBJECT_ID('tempdb..#tmpTbl') IS NOT NULL DROP TABLE #tmpTbl

-- get last 1 row
SELECT * INTO #tmpTbl FROM (SELECT TOP 1 * FROM (SELECT * FROM inserted
                                                 UNION 
                                                 SELECT * FROM deleted
                                                 ) AS A ORDER BY A.Date DESC
                            ) AS T


-- try catch
BEGIN TRY 

    INSERT INTO MyTable  (
           [Code]
          ,[Name]
           .....
          ,[Activity])
    SELECT [Code]
          ,[Name]
          ,@Activity 
    FROM #tmpTbl

END TRY BEGIN CATCH END CATCH


-- delete temp table
IF OBJECT_ID('tempdb..#tmpTbl') IS NOT NULL DROP TABLE #tmpTbl

SET NOCOUNT OFF;
END

How to create and write to a txt file using VBA

 
Dim SaveVar As Object

Sub Main()

    Console.WriteLine("Enter Text")

    Console.WriteLine("")

    SaveVar = Console.ReadLine

    My.Computer.FileSystem.WriteAllText("N:\A-Level Computing\2017!\PPE\SaveFile\SaveData.txt", "Text: " & SaveVar & ", ", True)

    Console.WriteLine("")

    Console.WriteLine("File Saved")

    Console.WriteLine("")

    Console.WriteLine(My.Computer.FileSystem.ReadAllText("N:\A-Level Computing\2017!\PPE\SaveFile\SaveData.txt"))
    Console.ReadLine()

End Sub()

How to convert an int to string in C?

Converting anything to a string should either 1) allocate the resultant string or 2) pass in a char * destination and size. Sample code below:

Both work for all int including INT_MIN. They provide a consistent output unlike snprintf() which depends on the current locale.

Method 1: Returns NULL on out-of-memory.

#define INT_DECIMAL_STRING_SIZE(int_type) ((CHAR_BIT*sizeof(int_type)-1)*10/33+3)

char *int_to_string_alloc(int x) {
  int i = x;
  char buf[INT_DECIMAL_STRING_SIZE(int)];
  char *p = &buf[sizeof buf - 1];
  *p = '\0';
  if (i >= 0) {
    i = -i;
  }
  do {
    p--;
    *p = (char) ('0' - i % 10);
    i /= 10;
  } while (i);
  if (x < 0) {
    p--;
    *p = '-';
  }
  size_t len = (size_t) (&buf[sizeof buf] - p);
  char *s = malloc(len);
  if (s) {
    memcpy(s, p, len);
  }
  return s;
}

Method 2: It returns NULL if the buffer was too small.

static char *int_to_string_helper(char *dest, size_t n, int x) {
  if (n == 0) {
    return NULL;
  }
  if (x <= -10) {
    dest = int_to_string_helper(dest, n - 1, x / 10);
    if (dest == NULL) return NULL;
  }
  *dest = (char) ('0' - x % 10);
  return dest + 1;
}

char *int_to_string(char *dest, size_t n, int x) {
  char *p = dest;
  if (n == 0) {
    return NULL;
  }
  n--;
  if (x < 0) {
    if (n == 0) return NULL;
    n--;
    *p++ = '-';
  } else {
    x = -x;
  }
  p = int_to_string_helper(p, n, x);
  if (p == NULL) return NULL;
  *p = 0;
  return dest;
}

[Edit] as request by @Alter Mann

(CHAR_BIT*sizeof(int_type)-1)*10/33+3 is at least the maximum number of char needed to encode the some signed integer type as a string consisting of an optional negative sign, digits, and a null character..

The number of non-sign bits in a signed integer is no more than CHAR_BIT*sizeof(int_type)-1. A base-10 representation of a n-bit binary number takes up to n*log10(2) + 1 digits. 10/33 is slightly more than log10(2). +1 for the sign char and +1 for the null character. Other fractions could be used like 28/93.

Method 3: If one wants to live on the edge and buffer overflow is not a concern, a simple C99 or later solution follows which handles all int.

#include <limits.h>
#include <stdio.h>

static char *itoa_simple_helper(char *dest, int i) {
  if (i <= -10) {
    dest = itoa_simple_helper(dest, i/10);
  }
  *dest++ = '0' - i%10;
  return dest;
}

char *itoa_simple(char *dest, int i) {
  char *s = dest;
  if (i < 0) {
    *s++ = '-';
  } else {
    i = -i;
  }
  *itoa_simple_helper(s, i) = '\0';
  return dest;
}

int main() {
  char s[100];
  puts(itoa_simple(s, 0));
  puts(itoa_simple(s, 1));
  puts(itoa_simple(s, -1));
  puts(itoa_simple(s, 12345));
  puts(itoa_simple(s, INT_MAX-1));
  puts(itoa_simple(s, INT_MAX));
  puts(itoa_simple(s, INT_MIN+1));
  puts(itoa_simple(s, INT_MIN));
}

Sample output

0
1
-1
12345
2147483646
2147483647
-2147483647
-2147483648

Using C# regular expressions to remove HTML tags

Use this method to remove tags:

public string From_To(string text, string from, string to)
{
    if (text == null)
        return null;
    string pattern = @"" + from + ".*?" + to;
    Regex rx = new Regex(pattern, RegexOptions.Compiled | RegexOptions.IgnoreCase);
    MatchCollection matches = rx.Matches(text);
    return matches.Count <= 0 ? text : matches.Cast<Match>().Where(match => !string.IsNullOrEmpty(match.Value)).Aggregate(text, (current, match) => current.Replace(match.Value, ""));
}

enable/disable zoom in Android WebView

hey there for anyone who might be looking for solution like this.. i had issue with scaling inside WebView so best way to do is in your java.class where you set all for webView put this two line of code: (webViewSearch is name of my webView -->webViewSearch = (WebView) findViewById(R.id.id_webview_search);)

// force WebView to show content not zoomed---------------------------------------------------------
    webViewSearch.getSettings().setLoadWithOverviewMode(true);
    webViewSearch.getSettings().setUseWideViewPort(true);

hibernate could not get next sequence value

Hibernate's PostgreSQL dialect isn't very bright. It doesn't know about your per-SERIAL sequences, and is assuming there's a global database-wide sequence called "hibernate_sequence" that it can use.

(UPDATE: It appears that newer Hibernate versions may use the default per-table sequences when GenerationType.IDENTITY is specified. Test your version and use this instead of the below if it works for you.)

You need to change your mappings to explicitly specify each sequence. It's annoying, repetitive, and pointless.

@Entity
@Table(name = "JUDGEMENTS")
public class Judgement implements Serializable, Cloneable {

    private static final long serialVersionUID = -7049957706738879274L;

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator="judgements_id_seq")
    @SequenceGenerator(name="judgements_id_seq", sequenceName="judgements_id_seq", allocationSize=1)
    @Column(name = "JUD_ID")
    private Long _judId;
...

The allocationSize=1 is quite important. If you omit it, Hibernate will blindly assume that the sequence is defined with INCREMENT 50 so when it gets a value from a sequence it can use that value and the 49 values below it as unique generated keys. If your database sequences increment by 1 - the default - then this will result in unique violations as Hibernate tries to re-use existing keys.

Note that getting one key at a time will result in an additional round trip per insert. As far as I can tell Hibernate isn't capable of using INSERT ... RETURNING to efficiently return generated keys, nor can it apparently use the JDBC generated keys interface. If you tell it to use a sequence, it'll call nextval to get the value then insert that explicitly, resulting in two round trips. To reduce the cost of that, you can set a greater increment on key sequences with lots of inserts , remembering to set it on the mapping and the underlying database sequence. That'll cause Hibernate to call nextval less frequently and cache blocks of keys to hand out as it goes.

I'm sure you can see from the above that I don't agree with the Hibernate design choices made here, at least from the perspective of using it with PostgreSQL. They should be using getGeneratedKeys or using INSERT ... RETURNING with DEFAULT for the key, letting the database take care of this without Hibernate having to trouble its self over the names of the sequences or explicit access to them.

BTW, if you're using Hibernate with Pg you'll possibly also want an oplock trigger for Pg to allow Hibernate's optimistic locking to interact safely with normal database locking. Without it or something like it your Hibernate updates will tend to clobber changes made via other regular SQL clients. Ask me how I know.

How to make a hyperlink in telegram without using bots?

On Telegram Desktop for macOS, the shortcuts differ. You can right-click a highlighted text, then hover over Transformations to see the available options:

macOS Telegram Desktop Formatting Shortcuts

How to set a variable to current date and date-1 in linux?

You can try:

#!/bin/bash
d=$(date +%Y-%m-%d)
echo "$d"

EDIT: Changed y to Y for 4 digit date as per QuantumFool's comment.

Default value for field in Django model

You can set the default like this:

b = models.CharField(max_length=7,default="foobar")

and then you can hide the field with your model's Admin class like this:

class SomeModelAdmin(admin.ModelAdmin):
    exclude = ("b")

ORA-12514 TNS:listener does not currently know of service requested in connect descriptor

tnslsnr is up but database is down.

For oracle novice it is not obvious that database may be down while connections are accepted.

I had to start up database manually like that

su - oracle
export ORACLE_SID=XE
sqlplus sys as sysdba

And then in sql console

startup

In my case i failed to startup but got another error message and found the source of a problem - i had to change host name and then database auto startup was functional again.

jQuery: click function exclude children.

My solution:

jQuery('.foo').on('click',function(event){
    if ( !jQuery(event.target).is('.foo *') ) {
        // code goes here
    } 
});

Is this the proper way to do boolean test in SQL?

In SQL Server you would generally use. I don't know about other database engines.

select * from users where active = 0

I am getting an "Invalid Host header" message when connecting to webpack-dev-server remotely

I found out, that I need to set the public property of devServer, to my request's host value. Being that it will be displayed at that external address.

So I needed this in my webpack.config.js

devServer: {
  compress: true,
  public: 'store-client-nestroia1.c9users.io' // That solved it
}

Another solution is using it on the CLI:

webpack-dev-server --public $C9_HOSTNAME <-- var for Cloud9 external IP

Convert a list of objects to an array of one of the object's properties

I am fairly sure that Linq can do this.... but MyList does not have a select method on it (which is what I would have used).

Yes, LINQ can do this. It's simply:

MyList.Select(x => x.Name).ToArray();

Most likely the issue is that you either don't have a reference to System.Core, or you are missing an using directive for System.Linq.

Injecting $scope into an angular service function()

Got into the same predicament. I ended up with the following. So here I am not injecting the scope object into the factory, but setting the $scope in the controller itself using the concept of promise returned by $http service.

(function () {
    getDataFactory = function ($http)
    {
        return {
            callWebApi: function (reqData)
            {
                var dataTemp = {
                    Page: 1, Take: 10,
                    PropName: 'Id', SortOrder: 'Asc'
                };

                return $http({
                    method: 'GET',
                    url: '/api/PatientCategoryApi/PatCat',
                    params: dataTemp, // Parameters to pass to external service
                    headers: { 'Content-Type': 'application/Json' }
                })                
            }
        }
    }
    patientCategoryController = function ($scope, getDataFactory) {
        alert('Hare');
        var promise = getDataFactory.callWebApi('someDataToPass');
        promise.then(
            function successCallback(response) {
                alert(JSON.stringify(response.data));
                // Set this response data to scope to use it in UI
                $scope.gridOptions.data = response.data.Collection;
            }, function errorCallback(response) {
                alert('Some problem while fetching data!!');
            });
    }
    patientCategoryController.$inject = ['$scope', 'getDataFactory'];
    getDataFactory.$inject = ['$http'];
    angular.module('demoApp', []);
    angular.module('demoApp').controller('patientCategoryController', patientCategoryController);
    angular.module('demoApp').factory('getDataFactory', getDataFactory);    
}());

Can iterators be reset in Python?

For DictReader:

f = open(filename, "rb")
d = csv.DictReader(f, delimiter=",")

f.seek(0)
d.__init__(f, delimiter=",")

For DictWriter:

f = open(filename, "rb+")
d = csv.DictWriter(f, fieldnames=fields, delimiter=",")

f.seek(0)
f.truncate(0)
d.__init__(f, fieldnames=fields, delimiter=",")
d.writeheader()
f.flush()

Disable JavaScript error in WebBrowser control

None of the above solutions were suitable for my scenario, handling .Navigated and .FileDownload events seemed like a good fit but accessing the WebBrowser.Document property threw an UnauthorizedAccessException which is caused by cross frame scripting security (our web content contains frames - all on the same domain/address but frames have their own security holes that are being blocked).

The solution that worked was to override IOleCommandTarget and to catch the script error commands at that level. Here's the WebBrowser sub-class to achieve this:

/// <summary>
/// Subclassed WebBrowser that suppresses error pop-ups.
/// 
/// Notes.
/// ScriptErrorsSuppressed property is not used because this actually suppresses *all* pop-ups.
/// 
/// More info at:
/// http://stackoverflow.com/questions/2476360/disable-javascript-error-in-webbrowser-control
/// </summary>
public class WebBrowserEx : WebBrowser
{
    #region Constructor

    /// <summary>
    /// Default constructor.
    /// Initialise browser control and attach customer event handlers.
    /// </summary>
    public WebBrowserEx()
    {
        this.ScriptErrorsSuppressed = false;
    }

    #endregion

    #region Overrides

    /// <summary>
    /// Override to allow custom script error handling.
    /// </summary>
    /// <returns></returns>
    protected override WebBrowserSiteBase CreateWebBrowserSiteBase()
    {
        return new WebBrowserSiteEx(this);
    }

    #endregion

    #region Inner Class [WebBrowserSiteEx]

    /// <summary>
    /// Sub-class to allow custom script error handling.
    /// </summary>
    protected class WebBrowserSiteEx : WebBrowserSite, NativeMethods.IOleCommandTarget
    {
        /// <summary>
        /// Default constructor.
        /// </summary>
        public WebBrowserSiteEx(WebBrowserEx webBrowser) : base (webBrowser)
        {   
        }

        /// <summary>Queries the object for the status of one or more commands generated by user interface events.</summary>
        /// <param name="pguidCmdGroup">The GUID of the command group.</param>
        /// <param name="cCmds">The number of commands in <paramref name="prgCmds" />.</param>
        /// <param name="prgCmds">An array of OLECMD structures that indicate the commands for which the caller needs status information. This method fills the <paramref name="cmdf" /> member of each structure with values taken from the OLECMDF enumeration.</param>
        /// <param name="pCmdText">An OLECMDTEXT structure in which to return name and/or status information of a single command. This parameter can be null to indicate that the caller does not need this information.</param>
        /// <returns>This method returns S_OK on success. Other possible return values include the following.
        /// E_FAIL The operation failed.
        /// E_UNEXPECTED An unexpected error has occurred.
        /// E_POINTER The <paramref name="prgCmds" /> argument is null.
        /// OLECMDERR_E_UNKNOWNGROUP The <paramref name="pguidCmdGroup" /> parameter is not null but does not specify a recognized command group.</returns>
        public int QueryStatus(ref Guid pguidCmdGroup, int cCmds, NativeMethods.OLECMD prgCmds, IntPtr pCmdText)
        {
            if((int)NativeMethods.OLECMDID.OLECMDID_SHOWSCRIPTERROR == prgCmds.cmdID)
            {   // Do nothing (suppress script errors)
                return NativeMethods.S_OK;
            }

            // Indicate that command is unknown. The command will then be handled by another IOleCommandTarget.
            return NativeMethods.OLECMDERR_E_UNKNOWNGROUP;
        }

        /// <summary>Executes the specified command.</summary>
        /// <param name="pguidCmdGroup">The GUID of the command group.</param>
        /// <param name="nCmdID">The command ID.</param>
        /// <param name="nCmdexecopt">Specifies how the object should execute the command. Possible values are taken from the <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMDEXECOPT" /> and <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMDID_WINDOWSTATE_FLAG" /> enumerations.</param>
        /// <param name="pvaIn">The input arguments of the command.</param>
        /// <param name="pvaOut">The output arguments of the command.</param>
        /// <returns>This method returns S_OK on success. Other possible return values include 
        /// OLECMDERR_E_UNKNOWNGROUP The <paramref name="pguidCmdGroup" /> parameter is not null but does not specify a recognized command group.
        /// OLECMDERR_E_NOTSUPPORTED The <paramref name="nCmdID" /> parameter is not a valid command in the group identified by <paramref name="pguidCmdGroup" />.
        /// OLECMDERR_E_DISABLED The command identified by <paramref name="nCmdID" /> is currently disabled and cannot be executed.
        /// OLECMDERR_E_NOHELP The caller has asked for help on the command identified by <paramref name="nCmdID" />, but no help is available.
        /// OLECMDERR_E_CANCELED The user canceled the execution of the command.</returns>
        public int Exec(ref Guid pguidCmdGroup, int nCmdID, int nCmdexecopt, object[] pvaIn, int pvaOut)
        {
            if((int)NativeMethods.OLECMDID.OLECMDID_SHOWSCRIPTERROR == nCmdID)
            {   // Do nothing (suppress script errors)
                return NativeMethods.S_OK;
            }

            // Indicate that command is unknown. The command will then be handled by another IOleCommandTarget.
            return NativeMethods.OLECMDERR_E_UNKNOWNGROUP;
        }
    }

    #endregion
}

~

/// <summary>
/// Native (unmanaged) methods, required for custom command handling for the WebBrowser control.
/// </summary>
public static class NativeMethods
{
    /// From docobj.h
    public const int OLECMDERR_E_UNKNOWNGROUP = -2147221244;

    /// <summary>
    /// From Microsoft.VisualStudio.OLE.Interop (Visual Studio 2010 SDK).
    /// </summary>
    public enum OLECMDID
    {
        /// <summary />
        OLECMDID_OPEN = 1,
        /// <summary />
        OLECMDID_NEW,
        /// <summary />
        OLECMDID_SAVE,
        /// <summary />
        OLECMDID_SAVEAS,
        /// <summary />
        OLECMDID_SAVECOPYAS,
        /// <summary />
        OLECMDID_PRINT,
        /// <summary />
        OLECMDID_PRINTPREVIEW,
        /// <summary />
        OLECMDID_PAGESETUP,
        /// <summary />
        OLECMDID_SPELL,
        /// <summary />
        OLECMDID_PROPERTIES,
        /// <summary />
        OLECMDID_CUT,
        /// <summary />
        OLECMDID_COPY,
        /// <summary />
        OLECMDID_PASTE,
        /// <summary />
        OLECMDID_PASTESPECIAL,
        /// <summary />
        OLECMDID_UNDO,
        /// <summary />
        OLECMDID_REDO,
        /// <summary />
        OLECMDID_SELECTALL,
        /// <summary />
        OLECMDID_CLEARSELECTION,
        /// <summary />
        OLECMDID_ZOOM,
        /// <summary />
        OLECMDID_GETZOOMRANGE,
        /// <summary />
        OLECMDID_UPDATECOMMANDS,
        /// <summary />
        OLECMDID_REFRESH,
        /// <summary />
        OLECMDID_STOP,
        /// <summary />
        OLECMDID_HIDETOOLBARS,
        /// <summary />
        OLECMDID_SETPROGRESSMAX,
        /// <summary />
        OLECMDID_SETPROGRESSPOS,
        /// <summary />
        OLECMDID_SETPROGRESSTEXT,
        /// <summary />
        OLECMDID_SETTITLE,
        /// <summary />
        OLECMDID_SETDOWNLOADSTATE,
        /// <summary />
        OLECMDID_STOPDOWNLOAD,
        /// <summary />
        OLECMDID_ONTOOLBARACTIVATED,
        /// <summary />
        OLECMDID_FIND,
        /// <summary />
        OLECMDID_DELETE,
        /// <summary />
        OLECMDID_HTTPEQUIV,
        /// <summary />
        OLECMDID_HTTPEQUIV_DONE,
        /// <summary />
        OLECMDID_ENABLE_INTERACTION,
        /// <summary />
        OLECMDID_ONUNLOAD,
        /// <summary />
        OLECMDID_PROPERTYBAG2,
        /// <summary />
        OLECMDID_PREREFRESH,
        /// <summary />
        OLECMDID_SHOWSCRIPTERROR,
        /// <summary />
        OLECMDID_SHOWMESSAGE,
        /// <summary />
        OLECMDID_SHOWFIND,
        /// <summary />
        OLECMDID_SHOWPAGESETUP,
        /// <summary />
        OLECMDID_SHOWPRINT,
        /// <summary />
        OLECMDID_CLOSE,
        /// <summary />
        OLECMDID_ALLOWUILESSSAVEAS,
        /// <summary />
        OLECMDID_DONTDOWNLOADCSS,
        /// <summary />
        OLECMDID_UPDATEPAGESTATUS,
        /// <summary />
        OLECMDID_PRINT2,
        /// <summary />
        OLECMDID_PRINTPREVIEW2,
        /// <summary />
        OLECMDID_SETPRINTTEMPLATE,
        /// <summary />
        OLECMDID_GETPRINTTEMPLATE
    }

    /// <summary>
    /// From Microsoft.VisualStudio.Shell (Visual Studio 2010 SDK).
    /// </summary>
    public const int S_OK = 0;

    /// <summary>
    /// OLE command structure.
    /// </summary>
    [StructLayout(LayoutKind.Sequential)]
    public class OLECMD
    {
        /// <summary>
        /// Command ID.
        /// </summary>
        [MarshalAs(UnmanagedType.U4)]
        public int cmdID;
        /// <summary>
        /// Flags associated with cmdID.
        /// </summary>
        [MarshalAs(UnmanagedType.U4)]
        public int cmdf;
    }

    /// <summary>
    /// Enables the dispatching of commands between objects and containers.
    /// </summary>
    [ComVisible(true), Guid("B722BCCB-4E68-101B-A2BC-00AA00404770"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    [ComImport]
    public interface IOleCommandTarget
    {
        /// <summary>Queries the object for the status of one or more commands generated by user interface events.</summary>
        /// <param name="pguidCmdGroup">The GUID of the command group.</param>
        /// <param name="cCmds">The number of commands in <paramref name="prgCmds" />.</param>
        /// <param name="prgCmds">An array of <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMD" /> structures that indicate the commands for which the caller needs status information.</param>
        /// <param name="pCmdText">An <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMDTEXT" /> structure in which to return name and/or status information of a single command. This parameter can be null to indicate that the caller does not need this information.</param>
        /// <returns>This method returns S_OK on success. Other possible return values include the following.
        /// E_FAIL The operation failed.
        /// E_UNEXPECTED An unexpected error has occurred.
        /// E_POINTER The <paramref name="prgCmds" /> argument is null.
        /// OLECMDERR_E_UNKNOWNGROUPThe <paramref name="pguidCmdGroup" /> parameter is not null but does not specify a recognized command group.</returns>
        [PreserveSig]
        [return: MarshalAs(UnmanagedType.I4)]
        int QueryStatus(ref Guid pguidCmdGroup, int cCmds, [In] [Out] NativeMethods.OLECMD prgCmds, [In] [Out] IntPtr pCmdText);

        /// <summary>Executes the specified command.</summary>
        /// <param name="pguidCmdGroup">The GUID of the command group.</param>
        /// <param name="nCmdID">The command ID.</param>
        /// <param name="nCmdexecopt">Specifies how the object should execute the command. Possible values are taken from the <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMDEXECOPT" /> and <see cref="T:Microsoft.VisualStudio.OLE.Interop.OLECMDID_WINDOWSTATE_FLAG" /> enumerations.</param>
        /// <param name="pvaIn">The input arguments of the command.</param>
        /// <param name="pvaOut">The output arguments of the command.</param>
        /// <returns>This method returns S_OK on success. Other possible return values include 
        /// OLECMDERR_E_UNKNOWNGROUP The <paramref name="pguidCmdGroup" /> parameter is not null but does not specify a recognized command group.
        /// OLECMDERR_E_NOTSUPPORTED The <paramref name="nCmdID" /> parameter is not a valid command in the group identified by <paramref name="pguidCmdGroup" />.
        /// OLECMDERR_E_DISABLED The command identified by <paramref name="nCmdID" /> is currently disabled and cannot be executed.
        /// OLECMDERR_E_NOHELP The caller has asked for help on the command identified by <paramref name="nCmdID" />, but no help is available.
        /// OLECMDERR_E_CANCELED The user canceled the execution of the command.</returns>
        [PreserveSig]
        [return: MarshalAs(UnmanagedType.I4)]
        int Exec(ref Guid pguidCmdGroup, int nCmdID, int nCmdexecopt, [MarshalAs(UnmanagedType.LPArray)] [In] object[] pvaIn, int pvaOut);
    }
}

A general tree implementation?

A tree in Python is quite simple. Make a class that has data and a list of children. Each child is an instance of the same class. This is a general n-nary tree.

class Node(object):
    def __init__(self, data):
        self.data = data
        self.children = []

    def add_child(self, obj):
        self.children.append(obj)

Then interact:

>>> n = Node(5)
>>> p = Node(6)
>>> q = Node(7)
>>> n.add_child(p)
>>> n.add_child(q)
>>> n.children
[<__main__.Node object at 0x02877FF0>, <__main__.Node object at 0x02877F90>]
>>> for c in n.children:
...   print c.data
... 
6
7
>>>

This is a very basic skeleton, not abstracted or anything. The actual code will depend on your specific needs - I'm just trying to show that this is very simple in Python.

Not class selector in jQuery

You need the :not() selector:

$('div[class^="first-"]:not(.first-bar)')

or, alternatively, the .not() method:

$('div[class^="first-"]').not('.first-bar');

How to call a REST web service API from JavaScript?

I think add if (this.readyState == 4 && this.status == 200) to wait is better:

var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
       // Typical action to be performed when the document is ready:
        var response = xhttp.responseText;
        console.log("ok"+response);
    }
};
xhttp.open("GET", "your url", true);

xhttp.send();

Write output to a text file in PowerShell

Use the Out-File cmdlet

 Compare-Object ... | Out-File C:\filename.txt

Optionally, add -Encoding utf8 to Out-File as the default encoding is not really ideal for many uses.

change values in array when doing foreach

Let's try to keep it simple and discuss how it is actually working. It has to do with variable types and function parameters.

Here is your code we are talking about:

var arr = ["one","two","three"];

arr.forEach(function(part) {
  part = "four";
  return "four";
})

alert(arr);

First off, here is where you should be reading about Array.prototype.forEach():

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/forEach

Second, let's talk briefly about value types in JavaScript.

Primitives (undefined, null, String, Boolean, Number) store an actual value.

ex: var x = 5;

Reference Types (custom objects) store the memory location of the object.

ex: var xObj = { x : 5 };

And third, how function parameters work.

In functions, parameters are always passed by value.

Because arr is an array of Strings, it's an array of primitive objects, which means they are stored by value.

So for your code above, this means that each time the forEach() iterates, part is equal to the same value as arr[index], but not the same object.

part = "four"; will change the part variable, but will leave arr alone.

The following code will change the values you desire:

var arr = ["one","two","three"];

arr.forEach(function(part, index) {
  arr[index] = "four";
});

alert(arr);

Now if array arr was an array of reference types, the following code will work because reference types store a memory location of an object instead of the actual object.

var arr = [{ num : "one" }, { num : "two"}, { num : "three"}];

arr.forEach(function(part, index) {
  // part and arr[index] point to the same object
  // so changing the object that part points to changes the object that arr[index] points to

  part.num = "four";
});

alert(arr[0].num);
alert(arr[1].num);
alert(arr[2].num);

The following illustrates that you can change part to point to a new object while leaving the objects stored in arr alone:

var arr = [{ num : "one" }, { num : "two"}, { num : "three"}];

arr.forEach(function(part, index) {
  // the following will not change the object that arr[index] points to because part now points at a new object
  part = 5;
});

alert(arr[0].num);
alert(arr[1].num);
alert(arr[2].num);

How to append binary data to a buffer in node.js

Updated Answer for Node.js ~>0.8

Node is able to concatenate buffers on its own now.

var newBuffer = Buffer.concat([buffer1, buffer2]);

Old Answer for Node.js ~0.6

I use a module to add a .concat function, among others:

https://github.com/coolaj86/node-bufferjs

I know it isn't a "pure" solution, but it works very well for my purposes.

dotnet ef not found in .NET Core 3

I had the same problem. I resolved, uninstalling all de the versions in my pc and then reinstall dotnet.

Best Way to do Columns in HTML/CSS

If you want to do multiple (3+) columns here is a great snippet that works perfectly and validates as valid HTML5:

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title>Multiple Colums</title>

        <!-- Styles -->
        <style>
            .flex-center {
                width: 100%;
                align-items: center;/*These two properties center vetically*/
                height: 100vh;/*These two properties center vetically*/
                display: flex;/*This is the attribute that separates into columns*/
                justify-content: center;
                text-align: center;
                position: relative;
            }
            .spaceOut {
                margin-left: 25px;
                margin-right: 25px;
            }
        </style>

    </head>
    <body>
        <section class="flex-center">
            <h4>Tableless Columns Example</h4><br />
            <div class="spaceOut">
                Column 1<br />
            </div>
            <div class="spaceOut">
                Column 2<br />
            </div>
            <div class="spaceOut">
                Column 3<br />
            </div>      
            <div class="spaceOut">
                Column 4<br />
            </div>
            <div class="spaceOut">
                Column 5<br />
            </div>
        </section>
    </body>
</html>

Get average color of image via Javascript

As pointed out in other answers, often what you really want the dominant color as opposed to the average color which tends to be brown. I wrote a script that gets the most common color and posted it on this gist

Parsing jQuery AJAX response

you must parse JSON string to become object

var dataObject = jQuery.parseJSON(data);

so you can call it like:

success: function (data) {
    var dataObject = jQuery.parseJSON(data);
    if (dataObject.success == 1) {
       var insertedGoalId = dataObject.inserted.goal_id;
       ...
       ...
    }
}

Math.random() versus Random.nextInt(int)

According to this example Random.nextInt(n) has less predictable output then Math.random() * n. According to [sorted array faster than an unsorted array][1] I think we can say Random.nextInt(n) is hard to predict.

usingRandomClass : time:328 milesecond.

usingMathsRandom : time:187 milesecond.

package javaFuction;
import java.util.Random;
public class RandomFuction 
{
    static int array[] = new int[9999];
    static long sum = 0;
    public static void usingMathsRandom() {
        for (int i = 0; i < 9999; i++) {
         array[i] = (int) (Math.random() * 256);
       }

        for (int i = 0; i < 9999; i++) {
            for (int j = 0; j < 9999; j++) {
                if (array[j] >= 128) {
                    sum += array[j];
                }
            }
        }
    }

    public static void usingRandomClass() {
        Random random = new Random();
        for (int i = 0; i < 9999; i++) {
            array[i] = random.nextInt(256);
        }

        for (int i = 0; i < 9999; i++) {
            for (int j = 0; j < 9999; j++) {
                if (array[j] >= 128) {
                    sum += array[j];
                }
            }

        }

    }

    public static void main(String[] args) {
        long start = System.currentTimeMillis();
        usingRandomClass();
        long end = System.currentTimeMillis();
        System.out.println("usingRandomClass " + (end - start));
        start = System.currentTimeMillis();
        usingMathsRandom();
        end = System.currentTimeMillis();
        System.out.println("usingMathsRandom " + (end - start));

    }

}

How to break out of nested loops?

A different approach is to refactor the code from two for loops into a for loop and one manual loop. That way the break in the manual loop applies to the outer loop. I used this once in a Gauss-Jordan Elimination which required three nested loops to process.

for (int i = 0; i < 1000; i++)
{
    int j = 0;

MANUAL_LOOP:;

    if (j < 1000)
    {
       if (condition)
       {
           break;
       }

       j++;
       goto MANUAL_LOOP;
    }
}

Disable browser's back button

Try this code. Worked for me. It basically changes the hash as soon as the page loads which changes recent history page by adding "1" on URL. So when you hit back button, it redirects to same page everytime.

 <script type="text/javascript">
    var storedHash = window.location.hash;
    function changeHashOnLoad() { window.location.hash = "1";}
    window.onhashchange = function () {
        window.location.hash = storedHash;
    }
</script>

<body onload="changeHashOnLoad(); ">

</bod>

INSTALL_FAILED_DUPLICATE_PERMISSION... C2D_MESSAGE

I had the same problem with a custom signature permission on Android-21 and solved it by making sure I was doing a complete uninstall.

This is an edge case that occurs when:

  1. An application defines a custom permission using signature level security
  2. You attempt to update the installed app with a version signed with a different key
  3. The test device is running Android 21 or newer with support for multiple users

Command line example

Here is a command-line transcript that demonstrates the issue and how to solve it. At this point a debug version is installed and I am trying to install a production version signed with the release key:

# This fails because the debug version defines the custom permission signed with a different key:

[root@localhost svn-android-apps]# . androidbuildscripts/my-adb-install Example release
920 KB/s (2211982 bytes in 2.347s)
        pkg: /data/local/tmp/Example-release.apk
Failure [INSTALL_FAILED_DUPLICATE_PERMISSION perm=com.example.android.example.PERMISSION_EXAMPLE_PLUGIN pkg=com.example.android.example]

# I use uninstall -k because apparently that is similar to uninstalling as a user
# by dragging the app out of the app tray:

[root@localhost svn-android-apps]# /android-sdk-linux/platform-tools/adb uninstall -k com.example.android.example
The -k option uninstalls the application while retaining the data/cache.
At the moment, there is no way to remove the remaining data.
You will have to reinstall the application with the same signature, and fully uninstall it.
If you truly wish to continue, execute 'adb shell pm uninstall -k com.example.android.example'

# Let's go ahead and do that:

[root@localhost svn-android-apps]# /android-sdk-linux/platform-tools/adb shell pm uninstall -k com.example.android.example
Success

# This fails again because the custom permission apparently is part of the data/cache
# that was not uninstalled:

[root@localhost svn-android-apps]# . androidbuildscripts/my-adb-install Example release
912 KB/s (2211982 bytes in 2.367s)
        pkg: /data/local/tmp/Example-release.apk
Failure [INSTALL_FAILED_DUPLICATE_PERMISSION perm=com.example.android.example.PERMISSION_EXAMPLE_PLUGIN pkg=com.example.android.example]

# In spite of the warning above, simply doing a full uninstall at this point turned out to 
# work (for me):

[root@localhost svn-android-apps]# /android-sdk-linux/platform-tools/adb uninstall com.example.android.example
Success

# Release version now successfully installs:

[root@localhost svn-android-apps]# . androidbuildscripts/my-adb-install Example release
898 KB/s (2211982 bytes in 2.405s)
        pkg: /data/local/tmp/Example-release.apk
Success

[root@localhost svn-android-apps]#

Eclipse example

Going in the opposite direction (trying to install a debug build from Eclipse when a release build is already installed), I get the following dialog:

Eclipse reinstall dialog

If you just answer yes at this point the install will succeed.

Device example

As pointed out in another answer, you can also go to an app info page in the device settings, click the overflow menu, and select "Uninstall for all users" to prevent this error.

Adding backslashes without escaping [Python]

The extra backslash is not actually added; it's just added by the repr() function to indicate that it's a literal backslash. The Python interpreter uses the repr() function (which calls __repr__() on the object) when the result of an expression needs to be printed:

>>> '\\'
'\\'
>>> print '\\'
\
>>> print '\\'.__repr__()
'\\'

PHP unable to load php_curl.dll extension

Insert to file httpd.conf

LoadFile "D:/DevKit/PHP7.1/libeay32.dll"
LoadFile "D:/DevKit/PHP7.1/libssh2.dll"
LoadFile "D:/DevKit/PHP7.1/ssleay32.dll"

Import SQL dump into PostgreSQL database

I believe that you want to run in psql:

\i C:/database/db-backup.sql

How to specify an element after which to wrap in css flexbox?

The only thing that appears to work is to set flex-wrap: wrap; on the container and them somehow make the child you want to break out after to fill the full width, so width: 100%; should work.

If, however, you can't stretch the element to 100% (for example, if it's an <img>), you can apply a margin to it, like width: 50px; margin-right: calc(100% - 50px).

ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired

Your table is already locked by some query. For example, you may have executed "select for update" and have not yet committed/rollbacked and fired another select query. Do a commit/rollback before executing your query.

How to get cumulative sum

Once the table is created - 

select 
    A.id, A.SomeNumt, SUM(B.SomeNumt) as sum
    from @t A, @t B where A.id >= B.id
    group by A.id, A.SomeNumt

order by A.id

Error: Cannot find module 'webpack'

Seems to be a common Windows problem. This fixed it for me:

Nodejs cannot find installed module on Windows?

"Add an environment variable called NODE_PATH and set it to %USERPROFILE%\Application Data\npm\node_modules (Windows XP), %AppData%\npm\node_modules (Windows 7), or wherever npm ends up installing the modules on your Windows flavor. To be done with it once and for all, add this as a System variable in the Advanced tab of the System Properties dialog (run control.exe sysdm.cpl,System,3)."

Note that you can't actually use another environment variable within the value of NODE_PATH. That is, don't just copy and paste that string above, but set it to an actual resolved path like C:\Users\MYNAME\AppData\Roaming\npm\node_modules

Why is vertical-align: middle not working on my span or div?

Here you have an example of two ways of doing a vertical alignment. I use them and they work pretty well. One is using absolute positioning and the other using flexbox.

Vertical Align Example

Using flexbox, you can align an element by itself inside another element with display: flex; using align-self. If you need to align it also horizontally, you can use align-items and justify-content in the container.

If you don't want to use flexbox, you can use the position property. If you make the container relative and the content absolute, the content will be able to move freely inside the container. So if you use top: 0; and left: 0; in the content, it will be positioned at the top left corner of the container.

Absolute positioning

Then, to align it, you just need to change the top and left references to 50%. This will position the content at the container center from the top left corner of the content.

Align in the middle of the container

So you need to correct this translating the content half its size to the left and top.

Absolute centered

PHPExcel Make first row bold

Try this

$objPHPExcel->getActiveSheet()->getStyle('A1:D1')->getFont()->setBold(true);

Error In PHP5 ..Unable to load dynamic library

Somehow the gmp.so file seems to have been deleted from my system. This is what fixed it for me:

sudo apt-get install --reinstall php5-gmp

How to get last key in an array?

A solution would be to use a combination of end and key (quoting) :

  • end() advances array 's internal pointer to the last element, and returns its value.
  • key() returns the index element of the current array position.

So, a portion of code such as this one should do the trick :

$array = array(
    'first' => 123,
    'second' => 456,
    'last' => 789, 
);

end($array);         // move the internal pointer to the end of the array
$key = key($array);  // fetches the key of the element pointed to by the internal pointer

var_dump($key);

Will output :

string 'last' (length=4)

i.e. the key of the last element of my array.

After this has been done the array's internal pointer will be at the end of the array. As pointed out in the comments, you may want to run reset() on the array to bring the pointer back to the beginning of the array.

visual c++: #include files from other projects in the same solution

#include has nothing to do with projects - it just tells the preprocessor "put the contents of the header file here". If you give it a path that points to the correct location (can be a relative path, like ../your_file.h) it will be included correctly.

You will, however, have to learn about libraries (static/dynamic libraries) in order to make such projects link properly - but that's another question.

Difference between text and varchar (character varying)

Somewhat OT: If you're using Rails, the standard formatting of webpages may be different. For data entry forms text boxes are scrollable, but character varying (Rails string) boxes are one-line. Show views are as long as needed.

How do I make an html link look like a button?

If you want nice button with rounded corners, then use this class:

_x000D_
_x000D_ 
.link_button {_x000D_
    -webkit-border-radius: 4px;_x000D_
    -moz-border-radius: 4px;_x000D_
    border-radius: 4px;_x000D_
    border: solid 1px #20538D;_x000D_
    text-shadow: 0 -1px 0 rgba(0, 0, 0, 0.4);_x000D_
    -webkit-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4), 0 1px 1px rgba(0, 0, 0, 0.2);_x000D_
    -moz-box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4), 0 1px 1px rgba(0, 0, 0, 0.2);_x000D_
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.4), 0 1px 1px rgba(0, 0, 0, 0.2);_x000D_
    background: #4479BA;_x000D_
    color: #FFF;_x000D_
    padding: 8px 12px;_x000D_
    text-decoration: none;_x000D_
}
_x000D_ 
<a href="#" class="link_button">Example</a>
_x000D_
_x000D_
_x000D_

Python - converting a string of numbers into a list of int

 
number_string = '0, 0, 0, 11, 0, 0, 0, 0, 0, 19, 0, 9, 0, 0, 0, 0, 0, 0, 11'

number_string = number_string.split(',')

number_string = [int(i) for i in number_string]

Fancybox doesn't work with jQuery v1.9.0 [ f.browser is undefined / Cannot read property 'msie' ]

Hi this is due to new version of the jQuery => 1.9.0

you can check the update : http://blog.jquery.com/2013/01/15/jquery-1-9-final-jquery-2-0-beta-migrate-final-released/

jQuery.Browser is deprecated. you can keep latest version by adding a migration script : http://code.jquery.com/jquery-migrate-1.0.0.js

replace :

<script src="http://code.jquery.com/jquery-latest.js"></script>

by :

<script src="http://code.jquery.com/jquery-latest.js"></script>
<script src="http://code.jquery.com/jquery-migrate-1.0.0.js"></script>

in your page and its working.

Get current date in DD-Mon-YYY format in JavaScript/Jquery

the DD-MM-YYYY is just one of the formats. The format of the jquery plugin, is based on this list: http://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html

Tested following code in chrome console:

test = new Date()
test.format('d-M-Y')
"15-Dec-2014"

Create comma separated strings C#?

You could override your object's ToString() method:

public override string ToString ()
{
    return string.Format ("{0},{1},{2}", this.number, this.id, this.whatever);
}

Check if inputs are empty using jQuery

Doing it on blur is too limited. It assumes there was focus on the form field, so I prefer to do it on submit, and map through the input. After years of dealing with fancy blur, focus, etc. tricks, keeping things simpler will yield more usability where it counts.

$('#signupform').submit(function() {
    var errors = 0;
    $("#signupform :input").map(function(){
         if( !$(this).val() ) {
              $(this).parents('td').addClass('warning');
              errors++;
        } else if ($(this).val()) {
              $(this).parents('td').removeClass('warning');
        }   
    });
    if(errors > 0){
        $('#errorwarn').text("All fields are required");
        return false;
    }
    // do the ajax..    
});

How To Save Canvas As An Image With canvas.toDataURL()?

You can try this; create a dummy HTML anchor, and download the image from there like...

// Convert canvas to image
document.getElementById('btn-download').addEventListener("click", function(e) {
    var canvas = document.querySelector('#my-canvas');

    var dataURL = canvas.toDataURL("image/jpeg", 1.0);

    downloadImage(dataURL, 'my-canvas.jpeg');
});

// Save | Download image
function downloadImage(data, filename = 'untitled.jpeg') {
    var a = document.createElement('a');
    a.href = data;
    a.download = filename;
    document.body.appendChild(a);
    a.click();
}

Change a Git remote HEAD to point to something besides master

Since you mention GitHub, to do it on their site simply go into your project, then...

admin > Default Branch > (choose something)

Done.

Converting a JToken (or string) to a given Type

 
var i2 = JsonConvert.DeserializeObject(obj["id"].ToString(), type);

throws a parsing exception due to missing quotes around the first argument (I think). I got it to work by adding the quotes:

var i2 = JsonConvert.DeserializeObject("\"" + obj["id"].ToString() + "\"", type);

How can I find out if an .EXE has Command-Line Options?

Invoke it from the shell, with an argument like /? or --help. Those are the usual help switches.

How to label each equation in align environment?

\tag also works in align*. Example:

\begin{align*}
  a(x)^{2} &= bx\tag{1}\\ 
  a(x)^{2} &= b\tag{2}\\ 
  ax &= b\tag{3}\\ 
  a(x)^{2}+bx &= c\tag{4}\\ 
  a(x)^{2}+c &= bx\tag{5}\\ 
  a(x)^{2} &= bx+c\tag{6}\\ \\ 
  Where\quad a, b, c \, \in N
\end{align*}

Output:

PDF output for \tag example

Apache Proxy: No protocol handler was valid

I am posting an answer here, since I had the same error message for a different reason.

This error message can happen, for example, if you are using apache httpd to proxy requests from a source on protocol A to target on protocol B.

Here is the example of my situation:

AH01144: No protocol handler was valid for the URL /sockjs-node/info (scheme 'ws').

In the case above, what was happening was simply the following. I had enabled mod proxy to proxy websocket requests to nodejs based on path /sockjs-node.

The problem is that node does not use the path /sockjs-node for websocket requests exclusively. It also uses this path for hosting REST entrypoints that deliver information about websockets.

In this manner, when the application would try to open http://localhost:7001/sockjs-node/info, apache httpd would be trying to route the rest call from HTTP protocol to to a Webscoket endpoint call. Node did not accept this.

This lead to the exception above.

So be mindful that even if you enable the right modules, if you try to do the wrong forwarding, this will end with apache httpd informing you that the protocol you tried to use on the target server is not valid.

Loop and get key/value pair for JSON array using jQuery

The best and perfect solution for this issue:

I tried the jQuery with the Ajax success responses, but it doesn't work so I invented my own and finally it works!

Click here to see the full solution

var rs = '{"test" : "Got it perfect!","message" : "Got it!"}';
eval("var toObject = "+ rs + ";");
alert(toObject.message);

Using pg_dump to only get insert statements from one table within database

If you want to DUMP your inserts into an .sql file:

  1. cd to the location which you want to .sql file to be located
  2. pg_dump --column-inserts --data-only --table=<table> <database> > my_dump.sql

Note the > my_dump.sql command. This will put everything into a sql file named my_dump

Python: call a function from string name

You can use a dictionary too.

def install():
    print "In install"

methods = {'install': install}

method_name = 'install' # set by the command line options
if method_name in methods:
    methods[method_name]() # + argument list of course
else:
    raise Exception("Method %s not implemented" % method_name)

Differences between SP initiated SSO and IDP initiated SSO

SP Initiated SSO

Bill the user: "Hey Jimmy, show me that report"

Jimmy the SP: "Hey, I'm not sure who you are yet. We have a process here so you go get yourself verified with Bob the IdP first. I trust him."

Bob the IdP: "I see Jimmy sent you here. Please give me your credentials."

Bill the user: "Hi I'm Bill. Here are my credentials."

Bob the IdP: "Hi Bill. Looks like you check out."

Bob the IdP: "Hey Jimmy. This guy Bill checks out and here's some additional information about him. You do whatever you want from here."

Jimmy the SP: "Ok cool. Looks like Bill is also in our list of known guests. I'll let Bill in."

IdP Initiated SSO

Bill the user: "Hey Bob. I want to go to Jimmy's place. Security is tight over there."

Bob the IdP: "Hey Jimmy. I trust Bill. He checks out and here's some additional information about him. You do whatever you want from here."

Jimmy the SP: "Ok cool. Looks like Bill is also in our list of known guests. I'll let Bill in."

I go into more detail here, but still keeping things simple: https://jorgecolonconsulting.com/saml-sso-in-simple-terms/.

From Arraylist to Array

 
ArrayList<String> a = new ArrayList<String>();
a.add( "test" );
@SuppressWarnings( "unused")
Object[] array = a.toArray();

It depends on what you want to achieve if you need to manipulate the array later it would cost more effort than keeping the string in the ArrayList. You have also random access with an ArrayList by list.get( index );

How can I play sound in Java?

There is an alternative to importing the sound files which works in both applets and applications: convert the audio files into .java files and simply use them in your code.

I have developed a tool which makes this process a lot easier. It simplifies the Java Sound API quite a bit.

http://stephengware.com/projects/soundtoclass/

How to access full source of old commit in BitBucket?

Search it for a long time, and finally, I found how to do it:)

Please check this image which illustrates steps. enter image description here

React Native version mismatch

I've never seen this error before, but whenever I can't get Xcode and React-Native to play well together, I do a couple of things. Check what version of Xcode I'm working with. If it needs to be updated, I update it. Then clearing watchman and the cache are the second place I go. I don't use the reset cache command. It always says that I need to verify the cache, so I skip that (you can do it though, I just get confused). I use rm -rf $TMPDIR/react-* to get rid of any cached builds. If that doesn't work, I try to build the app in Xcode, then work my way from there, to build it with react-native run-ios. With this error message, it seems you might start by trying to build it with Xcode. Hope that helps...let me know your progress with it. Good luck! (Also, you could update to RN 0.51 as another attempt to get your versions synced.)

How can I write these variables into one line of code in C#?

If you want to use something similar to the JavaScript, you just need to convert to strings first:

Console.WriteLine(mon.ToString() + "." + da.ToString() + "." + yer.ToString());

But a (much) better way would be to use the format option:

Console.WriteLine("{0}.{1}.{2}", mon, da, yer);

How to read a single character from the user?

This might be a use case for a context manager. Leaving aside allowances for Windows OS, here's my suggestion:

#!/usr/bin/env python3
# file: 'readchar.py'
"""
Implementation of a way to get a single character of input
without waiting for the user to hit <Enter>.
(OS is Linux, Ubuntu 14.04)
"""

import tty, sys, termios

class ReadChar():
    def __enter__(self):
        self.fd = sys.stdin.fileno()
        self.old_settings = termios.tcgetattr(self.fd)
        tty.setraw(sys.stdin.fileno())
        return sys.stdin.read(1)
    def __exit__(self, type, value, traceback):
        termios.tcsetattr(self.fd, termios.TCSADRAIN, self.old_settings)

def test():
    while True:
        with ReadChar() as rc:
            char = rc
        if ord(char) <= 32:
            print("You entered character with ordinal {}."\
                        .format(ord(char)))
        else:
            print("You entered character '{}'."\
                        .format(char))
        if char in "^C^D":
            sys.exit()

if __name__ == "__main__":
    test()

AngularJS : automatically detect change in model

And if you need to style your form elements according to it's state (modified/not modified) dynamically or to test whether some values has actually changed, you can use the following module, developed by myself: https://github.com/betsol/angular-input-modified

It adds additional properties and methods to the form and it's child elements. With it, you can test whether some element contains new data or even test if entire form has new unsaved data.

You can setup the following watch: $scope.$watch('myForm.modified', handler) and your handler will be called if some form elements actually contains new data or if it reversed to initial state.

Also, you can use modified property of individual form elements to actually reduce amount of data sent to a server via AJAX call. There is no need to send unchanged data.

As a bonus, you can revert your form to initial state via call to form's reset() method.

You can find the module's demo here: http://plnkr.co/edit/g2MDXv81OOBuGo6ORvdt?p=preview

Cheers!

How to use radio on change event?

Simple ES6 (javascript only) solution.

_x000D_
_x000D_ 
document.forms.demo.bedStatus.forEach(radio => {_x000D_
  radio.addEventListener('change', () => {_x000D_
    alert(`${document.forms.demo.bedStatus.value} Thai Gayo`);_x000D_
  })_x000D_
});
_x000D_ 
<form name="demo">_x000D_
  <input type="radio" name="bedStatus" value="Allot" checked>Allot_x000D_
  <input type="radio" name="bedStatus" value="Transfer">Transfer_x000D_
</form>
_x000D_
_x000D_
_x000D_

Where are the Properties.Settings.Default stored?

For anyone wondering where the settings for apps from the Microsoft Store are, they are either in WindowsApps, which is very locked down, but you can get there by opening your app and then opening the file path with Task-Manager.

But it's more likely that they are saved in C:\Users\[USERNAME]\AppData\Local\Packages\[NUMBERS][COMPANY].[APPLICATION]_[RANDOMDATA]\LocalCache\Local\[COMPANY]\[APPLICATION].exe_Url_[RANDOMDATA]\[VERSION]\user.config.

How to check if spark dataframe is empty?

If you do df.count > 0. It takes the counts of all partitions across all executors and add them up at Driver. This take a while when you are dealing with millions of rows.

The best way to do this is to perform df.take(1) and check if its null. This will return java.util.NoSuchElementException so better to put a try around df.take(1).

The dataframe return an error when take(1) is done instead of an empty row. I have highlighted the specific code lines where it throws the error.

enter image description here

What does the "+" (plus sign) CSS selector mean?

+ selector is called Adjacent Sibling Selector.

For example, the selector p + p, selects the p elements immediately following the p elements

It can be thought of as a looking outside selector which checks for the immediately following element.

Here is a sample snippet to make things more clear:

_x000D_
_x000D_ 
body {_x000D_
  font-family: Tahoma;_x000D_
  font-size: 12px;_x000D_
}_x000D_
p + p {_x000D_
  margin-left: 10px;_x000D_
}
_x000D_ 
<div>_x000D_
  <p>Header paragraph</p>_x000D_
  <p>This is a paragraph</p>_x000D_
  <p>This is another paragraph</p>_x000D_
  <p>This is yet another paragraph</p>_x000D_
  <hr>_x000D_
  <p>Footer paragraph</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Since we are one the same topic, it is worth mentioning another selector, ~ selector, which is General Sibling Selector

For example, p ~ p selects all the p which follows the p doesn't matter where it is, but both p should be having the same parent.

Here is how it looks like with the same markup:

_x000D_
_x000D_ 
body {_x000D_
  font-family: Tahoma;_x000D_
  font-size: 12px;_x000D_
}_x000D_
p ~ p {_x000D_
  margin-left: 10px;_x000D_
}
_x000D_ 
<div>_x000D_
  <p>Header paragraph</p>_x000D_
  <p>This is a paragraph</p>_x000D_
  <p>This is another paragraph</p>_x000D_
  <p>This is yet another paragraph</p>_x000D_
  <hr>_x000D_
  <p>Footer paragraph</p>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Notice that the last p is also matched in this sample.

Which is better, return value or out parameter?

I think one of the few scenarios where it would be useful would be when working with unmanaged memory, and you want to make it obvious that the "returned" value should be disposed of manually, rather than expecting it to be disposed of on its own.

How to check if memcache or memcached is installed for PHP?

The best approach in this case is to use extension_loaded() or function_exists() they are equally as fast.

You can see evidence here:

https://github.com/dragoonis/ppi-framework/blob/master/Cache/Memcached.php#L140

Bear in mind that some PHP extensions such as APC have php.ini settings that can disable them even though the extension may be loaded. Here is an example of how to check against that also:

https://github.com/dragoonis/ppi-framework/blob/master/Cache/Apc.php#L79

Hope this helps.

How to assign an exec result to a sql variable?

I always use the return value to pass back error status. If you need to pass back one value I'd use an output parameter.

sample stored procedure, with an OUTPUT parameter:

CREATE PROCEDURE YourStoredProcedure 
(
    @Param1    int
   ,@Param2    varchar(5)
   ,@Param3    datetime OUTPUT
)
AS
IF ISNULL(@Param1,0)>5
BEGIN
    SET @Param3=GETDATE()
END
ELSE
BEGIN
    SET @Param3='1/1/2010'
END
RETURN 0
GO

call to the stored procedure, with an OUTPUT parameter:

DECLARE @OutputParameter  datetime
       ,@ReturnValue      int

EXEC @ReturnValue=YourStoredProcedure 1,null, @OutputParameter OUTPUT
PRINT @ReturnValue
PRINT CONVERT(char(23),@OutputParameter ,121)

OUTPUT:

0
2010-01-01 00:00:00.000

How to update (append to) an href in jquery?

jQuery 1.4 has a new feature for doing this, and it rules. I've forgotten what it's called, but you use it like this:

$("a.directions-link").attr("href", function(i, href) {
  return href + '?q=testing';
});

That loops over all the elements too, so no need for $.each

How To Get Selected Value From UIPickerView

You can access the selected row for a given component using the following method:

- (NSInteger)selectedRowInComponent:(NSInteger)component

Otherwise, implementing the delegate function is the only other option.

Can I have an IF block in DOS batch file?

Maybe a bit late, but hope it hellps:

@echo off 

if %ERRORLEVEL% == 0 (
msg * 1st line WORKS FINE rem You can relpace msg * with any othe operation...
goto Continue1
)
:Continue1
If exist "C:\Python31" (
msg * 2nd line WORKS FINE rem You can relpace msg * with any othe operation...
    goto Continue2
)
:Continue2
If exist "C:\Python31\Lib\site-packages\PyQt4" (  
msg * 3th line WORKS FINE rem You can relpace msg * with any othe operation...
    goto Continue3
)
:Continue3
msg * 4th line WORKS FINE rem You can relpace msg * with any othe operation...
    goto Continue4
)
:Continue4
msg * "Tutto a posto" rem You can relpace msg * with any othe operation...
pause

Angular HTML binding

Just to post a little addition to all the great answers so far: If you are using [innerHTML] to render Angular components and are bummed about it not working like me, have a look at the ngx-dynamic-hooks library that I wrote to address this very issue.

With it, you can load components from dynamic strings/html without compromising security. It actually uses Angular's DOMSanitizer just like [innerHTML] does as well, but retains the ability to load components (in a safe manner).

See it in action in this Stackblitz.

how to kill the tty in unix

for example kill pts/0

pkill -9 -t pts/0

How to install pandas from pip on windows cmd?

pip install pandas make sure, this is 'pandas' not 'panda'

If you are not able to access pip, then got to C:\Python37\Scripts and run pip.exe install pandas.

Alternatively, you can add C:\Python37\Scripts in the env variables for windows machines. Hope this helps.

How can I prevent a window from being resized with tkinter?

You can use the minsize and maxsize to set a minimum & maximum size, for example:

def __init__(self,master):
    master.minsize(width=666, height=666)
    master.maxsize(width=666, height=666)

Will give your window a fixed width & height of 666 pixels.

Or, just using minsize

def __init__(self,master):
    master.minsize(width=666, height=666)

Will make sure your window is always at least 666 pixels large, but the user can still expand the window.

Remove carriage return in Unix

try this to convert dos file into unix file:

fromdos file

How to show first commit by 'git log'?

Not the most beautiful way of doing it I guess:

git log --pretty=oneline | wc -l

This gives you a number then

git log HEAD~<The number minus one>

How to write LDAP query to test if user is member of a group?

You should be able to create a query with this filter here:

(&(objectClass=user)(sAMAccountName=yourUserName)
  (memberof=CN=YourGroup,OU=Users,DC=YourDomain,DC=com))

and when you run that against your LDAP server, if you get a result, your user "yourUserName" is indeed a member of the group "CN=YourGroup,OU=Users,DC=YourDomain,DC=com

Try and see if this works!

If you use C# / VB.Net and System.DirectoryServices, this snippet should do the trick:

DirectoryEntry rootEntry = new DirectoryEntry("LDAP://dc=yourcompany,dc=com");

DirectorySearcher srch = new DirectorySearcher(rootEntry);
srch.SearchScope = SearchScope.Subtree;

srch.Filter = "(&(objectClass=user)(sAMAccountName=yourusername)(memberOf=CN=yourgroup,OU=yourOU,DC=yourcompany,DC=com))";

SearchResultCollection res = srch.FindAll();

if(res == null || res.Count <= 0) {
    Console.WriteLine("This user is *NOT* member of that group");
} else {
    Console.WriteLine("This user is INDEED a member of that group");
}

Word of caution: this will only test for immediate group memberships, and it will not test for membership in what is called the "primary group" (usually "cn=Users") in your domain. It does not handle nested memberships, e.g. User A is member of Group A which is member of Group B - that fact that User A is really a member of Group B as well doesn't get reflected here.

Marc

Hide div if screen is smaller than a certain width

Is your logic not round the wrong way in that example, you have it hiding when the screen is bigger than 1024. Reverse the cases, make the none in to a block and vice versa.

What are the main differences between JWT and OAuth authentication?

Firstly, we have to differentiate JWT and OAuth. Basically, JWT is a token format. OAuth is an authorization protocol that can use JWT as a token. OAuth uses server-side and client-side storage. If you want to do real logout you must go with OAuth2. Authentication with JWT token can not logout actually. Because you don't have an Authentication Server that keeps track of tokens. If you want to provide an API to 3rd party clients, you must use OAuth2 also. OAuth2 is very flexible. JWT implementation is very easy and does not take long to implement. If your application needs this sort of flexibility, you should go with OAuth2. But if you don't need this use-case scenario, implementing OAuth2 is a waste of time.

XSRF token is always sent to the client in every response header. It does not matter if a CSRF token is sent in a JWT token or not, because the CSRF token is secured with itself. Therefore sending CSRF token in JWT is unnecessary.

Can I call a function of a shell script from another shell script?

You can't directly call a function in another shell script.

You can move your function definitions into a separate file and then load them into your script using the . command, like this:

. /path/to/functions.sh

This will interpret functions.sh as if it's content were actually present in your file at this point. This is a common mechanism for implementing shared libraries of shell functions.

How to convert date to string and to date again?

Convert Date to String using this function

public String convertDateToString(Date date, String format) {
        String dateStr = null;
        DateFormat df = new SimpleDateFormat(format);
        try {
            dateStr = df.format(date);
        } catch (Exception ex) {
            System.out.println(ex);
        }
        return dateStr;
    }

From Convert Date to String in Java . And convert string to date again

public Date convertStringToDate(String dateStr, String format) {
        Date date = null;
        DateFormat df = new SimpleDateFormat(format);
        try {
            date = df.parse(dateStr);
        } catch (Exception ex) {
            System.out.println(ex);
        }
        return date;
    }

From Convert String to date in Java

Java 8, Streams to find the duplicate elements

I think basic solutions to the question should be as below:

Supplier supplier=HashSet::new; 
HashSet has=ls.stream().collect(Collectors.toCollection(supplier));

List lst = (List) ls.stream().filter(e->Collections.frequency(ls,e)>1).distinct().collect(Collectors.toList());

well, it is not recommended to perform a filter operation, but for better understanding, i have used it, moreover, there should be some custom filtration in future versions.

Convert HTML5 into standalone Android App

Create an Android app using Eclipse.

Create a layout that has a <WebView> control.

Move your HTML code to /assets folder.

Load webview with your file:///android_asset/ file.

And you have an android app!

How do I drag and drop files into an application?

Another common gotcha is thinking you can ignore the Form DragOver (or DragEnter) events. I typically use the Form's DragOver event to set the AllowedEffect, and then a specific control's DragDrop event to handle the dropped data.

MySQL 'create schema' and 'create database' - Is there any difference

Strictly speaking, the difference between Database and Schema is inexisting in MySql.

However, this is not the case in other database engines such as SQL Server. In SQL server:,

Every table belongs to a grouping of objects in the database called database schema. It's a container or namespace (Querying Microsoft SQL Server 2012)

By default, all the tables in SQL Server belong to a default schema called dbo. When you query a table that hasn't been allocated to any particular schema, you can do something like:

SELECT *
FROM your_table

which is equivalent to:

SELECT *
FROM dbo.your_table

Now, SQL server allows the creation of different schema, which gives you the possibility of grouping tables that share a similar purpose. That helps to organize the database.

For example, you can create an schema called sales, with tables such as invoices, creditorders (and any other related with sales), and another schema called lookup, with tables such as countries, currencies, subscriptiontypes (and any other table used as look up table).

The tables that are allocated to a specific domain are displayed in SQL Server Studio Manager with the schema name prepended to the table name (exactly the same as the tables that belong to the default dbo schema).

There are special schemas in SQL Server. To quote the same book:

There are several built-in database schemas, and they can't be dropped or altered:

1) dbo, the default schema.

2) guest contains objects available to a guest user ("guest user" is a special role in SQL Server lingo, with some default and highly restricted permissions). Rarely used.

3) INFORMATION_SCHEMA, used by the Information Schema Views

4) sys, reserved for SQL Server internal use exclusively

Schemas are not only for grouping. It is actually possible to give different permissions for each schema to different users, as described MSDN.

Doing this way, the schema lookup mentioned above could be made available to any standard user in the database (e.g. SELECT permissions only), whereas a table called supplierbankaccountdetails may be allocated in a different schema called financial, and to give only access to the users in the group accounts (just an example, you get the idea).

Finally, and quoting the same book again:

It isn't the same Database Schema and Table Schema. The former is the namespace of a table, whereas the latter refers to the table definition

Parsing ISO 8601 date in Javascript

According to MSDN, the JavaScript Date object does not provide any specific date formatting methods (as you may see with other programming languages). However, you can use a few of the Date methods and formatting to accomplish your goal:

function dateToString (date) {
  // Use an array to format the month numbers
  var months = [
    "January",
    "February",
    "March",
    ...
  ];

  // Use an object to format the timezone identifiers
  var timeZones = {
    "360": "EST",
    ...
  };

  var month = months[date.getMonth()];
  var day = date.getDate();
  var year = date.getFullYear();

  var hours = date.getHours();
  var minutes = date.getMinutes();
  var time = (hours > 11 ? (hours - 11) : (hours + 1)) + ":" + minutes + (hours > 11 ? "PM" : "AM");
  var timezone = timeZones[date.getTimezoneOffset()];

  // Returns formatted date as string (e.g. January 28, 2011 - 7:30PM EST)
  return month + " " + day + ", " + year + " - " + time + " " + timezone;
}

var date = new Date("2011-01-28T19:30:00-05:00");

alert(dateToString(date));

You could even take it one step further and override the Date.toString() method:

function dateToString () { // No date argument this time
  // Use an array to format the month numbers
  var months = [
    "January",
    "February",
    "March",
    ...
  ];

  // Use an object to format the timezone identifiers
  var timeZones = {
    "360": "EST",
    ...
  };

  var month = months[*this*.getMonth()];
  var day = *this*.getDate();
  var year = *this*.getFullYear();

  var hours = *this*.getHours();
  var minutes = *this*.getMinutes();
  var time = (hours > 11 ? (hours - 11) : (hours + 1)) + ":" + minutes + (hours > 11 ? "PM" : "AM");
  var timezone = timeZones[*this*.getTimezoneOffset()];

  // Returns formatted date as string (e.g. January 28, 2011 - 7:30PM EST)
  return month + " " + day + ", " + year + " - " + time + " " + timezone;
}

var date = new Date("2011-01-28T19:30:00-05:00");
Date.prototype.toString = dateToString;

alert(date.toString());

How do I add a Maven dependency in Eclipse?

I have faced same problem with maven dependencies, eg: unfortunetly your maven dependencies deleted from your buildpath,then you people get lot of exceptions,if you follow below process you can easily resolve this issue.

Right click on project >> maven >> updateProject >> selectProject >> OK

Trying to check if username already exists in MySQL database using PHP

Everything is fine, just one mistake is there. Change this:

$query = mysql_query("SELECT username FROM Users WHERE username=$username", $con);
$query = mysql_query("SELECT Count(*) FROM Users WHERE username=$username, $con");

if (mysql_num_rows($query) != 0)
{
    echo "Username already exists";
}
else
{
  ...
}

SELECT * will not work, use with SELECT COUNT(*).

How to use 'git pull' from the command line?

Try setting the HOME environment variable in Windows to your home folder (c:\users\username).

( you can confirm that this is the problem by doing echo $HOME in git bash and echo %HOME% in cmd - latter might not be available )

RequiredIf Conditional Validation Attribute

I got it to work on ASP.NET MVC 5

I saw many people interested in and suffering from this code and i know it's really confusing and disrupting for the first time.

Notes

  • worked on MVC 5 on both server and client side :D
  • I didn't install "ExpressiveAnnotations" library at all.
  • I'm taking about the Original code from "@Dan Hunex", Find him above

Tips To Fix This Error

"The type System.Web.Mvc.RequiredAttributeAdapter must have a public constructor which accepts three parameters of types System.Web.Mvc.ModelMetadata, System.Web.Mvc.ControllerContext, and ExpressiveAnnotations.Attributes.RequiredIfAttribute Parameter name: adapterType"

Tip #1: make sure that you're inheriting from 'ValidationAttribute' not from 'RequiredAttribute' 

 public class RequiredIfAttribute : ValidationAttribute, IClientValidatable { ...}

Tip #2: OR remove this entire line from 'Global.asax', It is not needed at all in the newer version of the code (after edit by @Dan_Hunex), and yes this line was a must in the old version ...

DataAnnotationsModelValidatorProvider.RegisterAdapter(typeof(RequiredIfAttribute), typeof(RequiredAttributeAdapter));

Tips To Get The Javascript Code Part Work

1- put the code in a new js file (ex:requiredIfValidator.js)

2- warp the code inside a $(document).ready(function(){........});

3- include our js file after including the JQuery validation libraries, So it look like this now :

@Scripts.Render("~/bundles/jqueryval")
<script src="~/Content/JS/requiredIfValidator.js"></script>

4- Edit the C# code

from

rule.ValidationParameters["dependentproperty"] = (context as ViewContext).ViewData.TemplateInfo.GetFullHtmlFieldId(PropertyName);

to

rule.ValidationParameters["dependentproperty"] = PropertyName;

and from

if (dependentValue.ToString() == DesiredValue.ToString())

to

if (dependentValue != null && dependentValue.ToString() == DesiredValue.ToString())

My Entire Code Up and Running

Global.asax

Nothing to add here, keep it clean

requiredIfValidator.js

create this file in ~/content or in ~/scripts folder

    $.validator.unobtrusive.adapters.add('requiredif', ['dependentproperty', 'desiredvalue'], function (options)
{
    options.rules['requiredif'] = options.params;
    options.messages['requiredif'] = options.message;
});


$(document).ready(function ()
{

    $.validator.addMethod('requiredif', function (value, element, parameters) {
        var desiredvalue = parameters.desiredvalue;
        desiredvalue = (desiredvalue == null ? '' : desiredvalue).toString();
        var controlType = $("input[id$='" + parameters.dependentproperty + "']").attr("type");
        var actualvalue = {}
        if (controlType == "checkbox" || controlType == "radio") {
            var control = $("input[id$='" + parameters.dependentproperty + "']:checked");
            actualvalue = control.val();
        } else {
            actualvalue = $("#" + parameters.dependentproperty).val();
        }
        if ($.trim(desiredvalue).toLowerCase() === $.trim(actualvalue).toLocaleLowerCase()) {
            var isValid = $.validator.methods.required.call(this, value, element, parameters);
            return isValid;
        }
        return true;
    });
});

_Layout.cshtml or the View

@Scripts.Render("~/bundles/jqueryval")
<script src="~/Content/JS/requiredIfValidator.js"></script>

RequiredIfAttribute.cs Class

create it some where in your project, For example in ~/models/customValidation/

    using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Web.Mvc;

namespace Your_Project_Name.Models.CustomValidation
{
    public class RequiredIfAttribute : ValidationAttribute, IClientValidatable
    {
        private String PropertyName { get; set; }
        private Object DesiredValue { get; set; }
        private readonly RequiredAttribute _innerAttribute;

        public RequiredIfAttribute(String propertyName, Object desiredvalue)
        {
            PropertyName = propertyName;
            DesiredValue = desiredvalue;
            _innerAttribute = new RequiredAttribute();
        }

        protected override ValidationResult IsValid(object value, ValidationContext context)
        {
            var dependentValue = context.ObjectInstance.GetType().GetProperty(PropertyName).GetValue(context.ObjectInstance, null);

            if (dependentValue != null && dependentValue.ToString() == DesiredValue.ToString())
            {
                if (!_innerAttribute.IsValid(value))
                {
                    return new ValidationResult(FormatErrorMessage(context.DisplayName), new[] { context.MemberName });
                }
            }
            return ValidationResult.Success;
        }

        public IEnumerable<ModelClientValidationRule> GetClientValidationRules(ModelMetadata metadata, ControllerContext context)
        {
            var rule = new ModelClientValidationRule
            {
                ErrorMessage = ErrorMessageString,
                ValidationType = "requiredif",
            };
            rule.ValidationParameters["dependentproperty"] = PropertyName;
            rule.ValidationParameters["desiredvalue"] = DesiredValue is bool ? DesiredValue.ToString().ToLower() : DesiredValue;

            yield return rule;
        }
    }
}

The Model 

    using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Web;
using Your_Project_Name.Models.CustomValidation;

namespace Your_Project_Name.Models.ViewModels
{

    public class CreateOpenActivity
    {
        public Nullable<int> ORG_BY_CD { get; set; }

        [RequiredIf("ORG_BY_CD", "5", ErrorMessage = "Coordinator ID is required")] // This means: IF 'ORG_BY_CD' is equal 5 (for the example)  > make 'COR_CI_ID_NUM' required and apply its all validation / data annotations
        [RegularExpression("[0-9]+", ErrorMessage = "Enter Numbers Only")]
        [MaxLength(9, ErrorMessage = "Enter a valid ID Number")]
        [MinLength(9, ErrorMessage = "Enter a valid ID Number")]
        public string COR_CI_ID_NUM { get; set; }
    }
}

The View

Nothing to note here actually ...

    @model Your_Project_Name.Models.ViewModels.CreateOpenActivity
@{
    ViewBag.Title = "Testing";
}

@using (Html.BeginForm()) 
{
    @Html.AntiForgeryToken()

    <div class="form-horizontal">
        <h4>CreateOpenActivity</h4>
        <hr />
        @Html.ValidationSummary(true, "", new { @class = "text-danger" })

        <div class="form-group">
            @Html.LabelFor(model => model.ORG_BY_CD, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.ORG_BY_CD, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.ORG_BY_CD, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            @Html.LabelFor(model => model.COR_CI_ID_NUM, htmlAttributes: new { @class = "control-label col-md-2" })
            <div class="col-md-10">
                @Html.EditorFor(model => model.COR_CI_ID_NUM, new { htmlAttributes = new { @class = "form-control" } })
                @Html.ValidationMessageFor(model => model.COR_CI_ID_NUM, "", new { @class = "text-danger" })
            </div>
        </div>

        <div class="form-group">
            <div class="col-md-offset-2 col-md-10">
                <input type="submit" value="Create" class="btn btn-default" />
            </div>
        </div>
    </div>
}

I may upload a project sample for this later ...

Hope this was helpful

Thank You

how to set JAVA_OPTS for Tomcat in Windows?

 
SET JAVA_HOME=C:\Applications\java\java_8
SET PATH=%PATH%;C:\Applications\java\java_8\bin
SET JAVA_OPTIONS=-d64 -Xms128g -Xmx128g

move div with CSS transition

 
transition-property:width;

This should work. you have to have browser dependent code

Styling the arrow on bootstrap tooltips

If you want to style only the colors of the tooltips do as follow:

.tooltip-inner { background-color: #000; color: #fff; }
.tooltip.top .tooltip-arrow { border-top-color: #000; }
.tooltip.right .tooltip-arrow { border-right-color: #000; }
.tooltip.bottom .tooltip-arrow { border-bottom-color: #000; }
.tooltip.left .tooltip-arrow { border-left-color: #000; }

What is the significance of load factor in HashMap?

What is load factor ?

The amount of capacity which is to be exhausted for the HashMap to increase its capacity ?

Why load factor ?

Load factor is by default 0.75 of the initial capacity (16) therefore 25% of the buckets will be free before there is an increase in the capacity & this makes many new buckets with new hashcodes pointing to them to exist just after the increase in the number of buckets.

Now why should you keep many free buckets & what is the impact of keeping free buckets on the performance ?

If you set the loading factor to say 1.0 then something very interesting might happen.

Say you are adding an object x to your hashmap whose hashCode is 888 & in your hashmap the bucket representing the hashcode is free , so the object x gets added to the bucket, but now again say if you are adding another object y whose hashCode is also 888 then your object y will get added for sure BUT at the end of the bucket (because the buckets are nothing but linkedList implementation storing key,value & next) now this has a performance impact ! Since your object y is no longer present in the head of the bucket if you perform a lookup the time taken is not going to be O(1) this time it depends on how many items are there in the same bucket. This is called hash collision by the way & this even happens when your loading factor is less than 1.

Correlation between performance , hash collision & loading factor ?

Lower load factor = more free buckets = less chances of collision = high performance = high space requirement.

Correct me if i am wrong somewhere.

Increase permgen space

On Debian-like distributions you set that in /etc/default/tomcat[67]

How can I edit javascript in my browser like I can use Firebug to edit CSS/HTML?

Firefox Developer Edition (59.0b6) has Scratchpad (Shift +F4) where you can run javascript

Safely remove migration In Laravel

You likely need to delete the entry from the migrations table too.

How to set cursor position in EditText?

 
EditText editText = findViewById(R.id.editText);
editText.setSelection(editText.getText().length());

Is There a Better Way of Checking Nil or Length == 0 of a String in Ruby?

As it was said here before Rails (ActiveSupport) have a handy blank? method and it is implemented like this:

class Object
  def blank?
    respond_to?(:empty?) ? empty? : !self
  end
end

Pretty easy to add to any ruby-based project.

The beauty of this solution is that it works auto-magicaly not only for Strings but also for Arrays and other types.

PHP: Return all dates between two dates in an array

 
// will return dates array
function returnBetweenDates( $startDate, $endDate ){
    $startStamp = strtotime(  $startDate );
    $endStamp   = strtotime(  $endDate );

    if( $endStamp > $startStamp ){
        while( $endStamp >= $startStamp ){

            $dateArr[] = date( 'Y-m-d', $startStamp );

            $startStamp = strtotime( ' +1 day ', $startStamp );

        }
        return $dateArr;    
    }else{
        return $startDate;
    }

}

returnBetweenDates( '2014-09-16', '2014-09-26' );

// print_r( returnBetweenDates( '2014-09-16', '2014-09-26' ) );

it will return array like below:

Array
(
    [0] => 2014-09-16
    [1] => 2014-09-17
    [2] => 2014-09-18
    [3] => 2014-09-19
    [4] => 2014-09-20
    [5] => 2014-09-21
    [6] => 2014-09-22
    [7] => 2014-09-23
    [8] => 2014-09-24
    [9] => 2014-09-25
    [10] => 2014-09-26
)

ASP.net vs PHP (What to choose)

You can have great success and great performance either way. MSDN runs off of ASP.NET so you know it can perform well. PHP runs a lot of the top websites in the world. The same can be said of the databases as well. You really need to choose based upon your skills, the skills of your team, possible specific features that you need/want that one does better than the other, and even the servers that you want to run this site.

If I were building it, I would lean towards PHP because probably everything you want to do has been done before (with code examples how) and because hosting is so much easier to get (and cheaper because you don't have the licensing issues to deal with compared to Windows hosting). For the same reason, I would choose MySQL as well. It is a great database platform and the price is right.

Multiple selector chaining in jQuery?

like:

$('#Create .myClass, #Edit .myClass').plugin({ 
    options: here
});

You can specify any number of selectors to combine into a single result. This multiple expression combinator is an efficient way to select disparate elements. The order of the DOM elements in the returned jQuery object may not be identical, as they will be in document order. An alternative to this combinator is the .add() method.

Trigger css hover with JS

You can't. It's not a trusted event.

Events that are generated by the user agent, either as a result of user interaction, or as a direct result of changes to the DOM, are trusted by the user agent with privileges that are not afforded to events generated by script through the DocumentEvent.createEvent("Event") method, modified using the Event.initEvent() method, or dispatched via the EventTarget.dispatchEvent() method. The isTrusted attribute of trusted events has a value of true, while untrusted events have a isTrusted attribute value of false.

Most untrusted events should not trigger default actions, with the exception of click or DOMActivate events.

You have to add a class and add/remove that on the mouseover/mouseout events manually.

Side note, I'm answering this here after I marked this as a duplicate since no answer here really covers the issue from what I see. Hopefully, one day it'll be merged.

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax — PHP — PDO

Same pdo error in sql query while trying to insert into database value from multidimential array:

$sql = "UPDATE test SET field=arr[$s][a] WHERE id = $id";
$sth = $db->prepare($sql);    
$sth->execute();

Extracting array arr[$s][a] from sql query, using instead variable containing it fixes the problem.

When running WebDriver with Chrome browser, getting message, "Only local connections are allowed" even though browser launches properly

I had to run my commands in the one and same terminal, not seperately.

nohup sudo Xvfb :10 -ac
export DISPLAY=:10
java -jar vendor/se/selenium-server-standalone/bin/selenium-server-standalone.jar -Dwebdriver.chrome.bin="/usr/bin/google-chrome" -Dwebdriver.chrome.driver="vendor/bin/chromedriver"

How to set Meld as git mergetool

This worked for me on Windows 8.1 and Windows 10.

git config --global mergetool.meld.path "/c/Program Files (x86)/meld/meld.exe"

How do I fix PyDev "Undefined variable from import" errors?

I find that these 2 steps work for me all the time:

  1. Confirm (else add) the parent folder of the module to the PYTHONPATH.
  2. Add FULL name of the module to forced builtins.

The things to note here:

  • Some popular modules install with some parent and child pair having the same name. In these cases you also have to add that parent to PYTHONPATH, in addition to its grandparent folder, which you already confirmed/added for everything else.

  • Use (for example) "google.appengine.api.memcache" when adding to forced builtins, NOT "memcache" only, where "google" in this example, is an immediate child of a folder defined in PYTHONPATH.

Casting LinkedHashMap to Complex Object

I had similar Issue where we have GenericResponse object containing list of values

 ResponseEntity<ResponseDTO> responseEntity = restTemplate.exchange(
                redisMatchedDriverUrl,
                HttpMethod.POST,
                requestEntity,
                ResponseDTO.class
        );

Usage of objectMapper helped in converting LinkedHashMap into respective DTO objects

 ObjectMapper mapper = new ObjectMapper();

 List<DriverLocationDTO> driverlocationsList = mapper.convertValue(responseDTO.getData(), new TypeReference<List<DriverLocationDTO>>() { });

Convert AM/PM time to 24 hours format?

Convert a string to a DateTime, you could try

    DateTime timeValue = Convert.ToDateTime("01:00 PM");
    Console.WriteLine(timeValue.ToString("HH:mm"));

Python, how to read bytes from file and save it?

Here's how to do it with the basic file operations in Python. This opens one file, reads the data into memory, then opens the second file and writes it out.

in_file = open("in-file", "rb") # opening for [r]eading as [b]inary
data = in_file.read() # if you only wanted to read 512 bytes, do .read(512)
in_file.close()

out_file = open("out-file", "wb") # open for [w]riting as [b]inary
out_file.write(data)
out_file.close()

We can do this more succinctly by using the with keyboard to handle closing the file.

with open("in-file", "rb") as in_file, open("out-file", "wb") as out_file:
    out_file.write(in_file.read())

If you don't want to store the entire file in memory, you can transfer it in pieces.

piece_size = 4096 # 4 KiB

with open("in-file", "rb") as in_file, open("out-file", "wb") as out_file:
    while True:
        piece = in_file.read(piece_size)

        if piece == "":
            break # end of file

        out_file.write(piece)

What is .Net Framework 4 extended?

Got this from Bing. Seems Microsoft has removed some features from the core framework and added it to a separate optional(?) framework component.

To quote from MSDN (http://msdn.microsoft.com/en-us/library/cc656912.aspx)

The .NET Framework 4 Client Profile does not include the following features. You must install the .NET Framework 4 to use these features in your application:

* ASP.NET
* Advanced Windows Communication Foundation (WCF) functionality
* .NET Framework Data Provider for Oracle
* MSBuild for compiling

I want to convert std::string into a const wchar_t *

First convert it to std::wstring:

std::wstring widestr = std::wstring(str.begin(), str.end());

Then get the C string:

const wchar_t* widecstr = widestr.c_str();

This only works for ASCII strings, but it will not work if the underlying string is UTF-8 encoded. Using a conversion routine like MultiByteToWideChar() ensures that this scenario is handled properly.

Npm install cannot find module 'semver'

On MS Windows, the solution is to remove %APPDATA%\npm and reinstall node

Appending an id to a list if not already present in a string

Your list just contains a string. Convert it to integer IDs:

L = ['350882 348521 350166\r\n']

ids = [int(i) for i in L[0].strip().split()]
print(ids)
id = 348521
if id not in ids:
    ids.append(id)
print(ids)
id = 348522
if id not in ids:
    ids.append(id)
print(ids)
# Turn it back into your odd format
L = [' '.join(str(id) for id in ids) + '\r\n']
print(L)

Output:

[350882, 348521, 350166]
[350882, 348521, 350166]
[350882, 348521, 350166, 348522]
['350882 348521 350166 348522\r\n']

jQuery Data vs Attr?

You can use data-* attribute to embed custom data. The data-* attributes gives us the ability to embed custom data attributes on all HTML elements.

jQuery .data() method allows you to get/set data of any type to DOM elements in a way that is safe from circular references and therefore from memory leaks.

jQuery .attr() method get/set attribute value for only the first element in the matched set.

Example:

<span id="test" title="foo" data-kind="primary">foo</span>

$("#test").attr("title");
$("#test").attr("data-kind");
$("#test").data("kind");
$("#test").data("value", "bar");

Valid values for android:fontFamily and what they map to?

Where do these values come from? The documentation for android:fontFamily does not list this information in any place

These are indeed not listed in the documentation. But they are mentioned here under the section 'Font families'. The document lists every new public API for Android Jelly Bean 4.1.

In the styles.xml file in the application I'm working on somebody listed this as the font family, and I'm pretty sure it's wrong:

Yes, that's wrong. You don't reference the font file, you have to use the font name mentioned in the linked document above. In this case it should have been this:

<item name="android:fontFamily">sans-serif</item>

Like the linked answer already stated, 12 variants are possible:

Added in Android Jelly Bean (4.1) - API 16 :

Regular (default):

<item name="android:fontFamily">sans-serif</item>
<item name="android:textStyle">normal</item>

Italic:

<item name="android:fontFamily">sans-serif</item>
<item name="android:textStyle">italic</item>

Bold:

<item name="android:fontFamily">sans-serif</item>
<item name="android:textStyle">bold</item>

Bold-italic:

<item name="android:fontFamily">sans-serif</item>
<item name="android:textStyle">bold|italic</item>

Light:

<item name="android:fontFamily">sans-serif-light</item>
<item name="android:textStyle">normal</item>

Light-italic:

<item name="android:fontFamily">sans-serif-light</item>
<item name="android:textStyle">italic</item>

Thin :

<item name="android:fontFamily">sans-serif-thin</item>
<item name="android:textStyle">normal</item>

Thin-italic :

<item name="android:fontFamily">sans-serif-thin</item>
<item name="android:textStyle">italic</item>

Condensed regular:

<item name="android:fontFamily">sans-serif-condensed</item>
<item name="android:textStyle">normal</item>

Condensed italic:

<item name="android:fontFamily">sans-serif-condensed</item>
<item name="android:textStyle">italic</item>

Condensed bold:

<item name="android:fontFamily">sans-serif-condensed</item>
<item name="android:textStyle">bold</item>

Condensed bold-italic:

<item name="android:fontFamily">sans-serif-condensed</item>
<item name="android:textStyle">bold|italic</item>

Added in Android Lollipop (v5.0) - API 21 :

Medium:

<item name="android:fontFamily">sans-serif-medium</item>
<item name="android:textStyle">normal</item>

Medium-italic:

<item name="android:fontFamily">sans-serif-medium</item>
<item name="android:textStyle">italic</item>

Black:

<item name="android:fontFamily">sans-serif-black</item>
<item name="android:textStyle">italic</item>

For quick reference, this is how they all look like:

Sending emails with Javascript

You don't need any javascript, you just need your href to be coded like this:

<a href="mailto:[email protected]">email me here!</a>

What tools do you use to test your public REST API?

I am using Fiddler - this is a great tool and allows you to quickly hack on previous http request amending headers / content etc.

Apart from that I am using scipts written in Python (using httplib) , as this is one of the easiest way to create integration test.

Why is January month 0 in Java Calendar?

I'd say laziness. Arrays start at 0 (everyone knows that); the months of the year are an array, which leads me to believe that some engineer at Sun just didn't bother to put this one little nicety into the Java code.

How do I get the width and height of a HTML5 canvas?

Well, all the answers before aren't entirely correct. 2 of major browsers don't support those 2 properties (IE is one of them) or use them differently.

Better solution (supported by most browsers, but I didn't check Safari):

var canvas = document.getElementById('mycanvas');
var width = canvas.scrollWidth;
var height = canvas.scrollHeight;

At least I get correct values with scrollWidth and -Height and MUST set canvas.width and height when it is resized.

How to find Current open Cursors in Oracle

1)your id should have sys dba access 2) 

select sum(a.value) total_cur, avg(a.value) avg_cur, max(a.value) max_cur, 
 s.username, s.machine
 from v$sesstat a, v$statname b, v$session s 
 where a.statistic# = b.statistic# and s.sid=a.sid
 and b.name = 'opened cursors current' 
 group by s.username, s.machine
 order by 1 desc;

How can I format a number into a string with leading zeros?

If you like to keep it fixed width, for example 10 digits, do it like this

Key = i.ToString("0000000000");

Replace with as many digits as you like.

i = 123 will then result in Key = "0000000123".

JBoss default password

just commenting the line of user and password in file ./server/default/conf/props jmx-console-users.properties worked for me

How to open Atom editor from command line in OS X?

I had the same issue which I resolved by first moving Atom.app from downloads to Applications. Then under Atom's menu options, I selected "Install Shell Commands".

Excel VBA: Copying multiple sheets into new workbook

This worked for me (I added an "if sheet visible" because in my case I wanted to skip hidden sheets)

   Sub Create_new_file()

Application.DisplayAlerts = False

Dim wb As Workbook
Dim wbNew As Workbook
Dim sh As Worksheet
Dim shNew As Worksheet
Dim pname, parea As String


Set wb = ThisWorkbook
Workbooks.Add
Set wbNew = ActiveWorkbook

For Each sh In wb.Worksheets

    pname = sh.Name


    If sh.Visible = True Then

    sh.Copy After:=wbNew.Sheets(Sheets.Count)

    wbNew.Sheets(Sheets.Count).Cells.ClearContents
    wbNew.Sheets(Sheets.Count).Cells.ClearFormats
    wb.Sheets(sh.Name).Activate
    Range(sh.PageSetup.PrintArea).Select
    Selection.Copy

    wbNew.Sheets(pname).Activate
    Range("A1").Select

    With Selection

        .PasteSpecial (xlValues)
        .PasteSpecial (xlFormats)
        .PasteSpecial (xlPasteColumnWidths)

    End With

    ActiveSheet.Name = pname

    End If


Next

wbNew.Sheets("Hoja1").Delete

Application.DisplayAlerts = True

End Sub

Can I call jQuery's click() to follow an <a> link if I haven't bound an event handler to it with bind or click already?

You can use jQuery to select the jQuery object for that element. Then, get the underlying DOM element and call its click() method.

By id:

$("#my-link").each(function (index) { $(this).get(0).click() });

Or use jQuery to click a bunch of links by CSS class:

$(".my-link-class").each(function (index) { $(this).get(0).click() });

How do I put a variable inside a string?

In general, you can create strings using:

stringExample = "someString " + str(someNumber)
print(stringExample)
plot.savefig(stringExample)

Hex colors: Numeric representation for "transparent"?

You can use this conversion table: http://roselab.jhu.edu/~raj/MISC/hexdectxt.html

eg, if you want a transparency of 60%, you use 3C (hex equivalent).

This is usefull for IE background gradient transparency:

filter:progid:DXImageTransform.Microsoft.gradient(startColorstr=#3C545454, endColorstr=#3C545454);
-ms-filter: "progid:DXImageTransform.Microsoft.gradient(startColorstr=#3C545454, endColorstr=#3C545454)";

where startColorstr and endColorstr: 2 first characters are a hex value for transparency, and the six remaining are the hex color.

Using Java 8's Optional with Stream::flatMap

If you're stuck with Java 8 but have access to Guava 21.0 or newer, you can use Streams.stream to convert an optional into a stream.

Thus, given

import com.google.common.collect.Streams;

you can write

Optional<Other> result =
    things.stream()
        .map(this::resolve)
        .flatMap(Streams::stream)
        .findFirst();

Forking vs. Branching in GitHub

Forking creates an entirely new repository from existing repository (simply doing git clone on gitHub/bitbucket)

Forks are best used: when the intent of the ‘split’ is to create a logically independent project, which may never reunite with its parent.

Branch strategy creates a new branch over the existing/working repository

Branches are best used: when they are created as temporary places to work through a feature, with the intent to merge the branch with the origin.

More Specific :- In open source projects it is the owner of the repository who decides who can push to the repository. However, the idea of open source is that everybody can contribute to the project.

This problem is solved by forks: any time a developer wants to change something in an open source project, they don’t clone the official repository directly. Instead, they fork it to create a copy. When the work is finished, they make a pull request so that the owner of the repository can review the changes and decide whether to merge them to his project.

At its core forking is similar to feature branching, but instead of creating branches a fork of the repository is made, and instead of doing a merge request you create a pull request.

The below links provide the difference in a well-explained manner :

https://blog.gitprime.com/the-definitive-guide-to-forks-and-branches-in-git/

https://buddy.works/blog/5-types-of-git-workflows

http://www.continuousagile.com/unblock/branching.html

How to Git stash pop specific stash in 1.8.3?

 
git stash apply n

works as of git version 2.11

Original answer, possibly helping to debug issues with the older syntax involving shell escapes:

As pointed out previously, the curly braces may require escaping or quoting depending on your OS, shell, etc.

See "stash@{1} is ambiguous?" for some detailed hints of what may be going wrong, and how to work around it in various shells and platforms.

git stash list
git stash apply stash@{n}

git stash apply version

The default XML namespace of the project must be the MSBuild XML namespace

If getting this error trying to build .Net Core 2.0 app on VSTS then ensure your build definition is using the Hosted VS2017 Agent queue.

Stratified Train/Test-split in scikit-learn

Here's an example for continuous/regression data (until this issue on GitHub is resolved).

min = np.amin(y)
max = np.amax(y)

# 5 bins may be too few for larger datasets.
bins     = np.linspace(start=min, stop=max, num=5)
y_binned = np.digitize(y, bins, right=True)

X_train, X_test, y_train, y_test = train_test_split(
    X, 
    y, 
    stratify=y_binned
)
  • Where start is min and stop is max of your continuous target.
  • If you don't set right=True then it will more or less make your max value a separate bin and your split will always fail because too few samples will be in that extra bin.

java.lang.OutOfMemoryError: Java heap space

  1. In most of the cases, the code is not optimized. Release those objects which you think shall not be needed further. Avoid creation of objects in your loop each time. Try to use caches. I don't know how your application is doing. But In programming, one rule of normal life applies as well

    Prevention is better than cure. "Don't create unnecessary objects"

Set selected option of select box

I had a problem where the value was not set because of a syntax error before the call.

$("#someId").value(33); //script bailed here without showing any errors Note: .value instead of .val
$("#gate").val('Gateway 2'); //this line didn't work.

Check for syntax errors before the call.

Declaring an HTMLElement Typescript

Okay: weird syntax!

var el: HTMLElement = document.getElementById('content');

fixes the problem. I wonder why the example didn't do this in the first place?

complete code:

class Greeter {
    element: HTMLElement;
    span: HTMLElement;
    timerToken: number;

    constructor (element: HTMLElement) { 
        this.element = element;
        this.element.innerText += "The time is: ";
        this.span = document.createElement('span');
        this.element.appendChild(this.span);
        this.span.innerText = new Date().toUTCString();
    }

    start() {
        this.timerToken = setInterval(() => this.span.innerText = new Date().toUTCString(), 500);
    }

    stop() {
        clearTimeout(this.timerToken);
    }

}

window.onload = () => {
    var el: HTMLElement = document.getElementById('content');
    var greeter = new Greeter(el);
    greeter.start();
};

webpack is not recognized as a internal or external command,operable program or batch file

I had this same problem and I couldn't figure it out. I went through every line of code and couldn't find my error. Then I realized that I installed webpack in the wrong folder. My error was not paying attention to the folder I was installing webpack to.

Submit form without page reloading

The page will get reloaded if you don't want to use javascript

Angular update object in object array

You can use for loop to find your element and update it:

updateItem(newItem){
  for (let i = 0; i < this.itemsArray.length; i++) {
      if(this.itemsArray[i].id == newItem.id){
        this.users[i] = newItem;
      }
    }
}

How to get the sizes of the tables of a MySQL database?

This should be tested in mysql, not postgresql:

SELECT table_schema, # "DB Name", 
Round(Sum(data_length + index_length) / 1024 / 1024, 1) # "DB Size in MB" 
FROM   information_schema.tables 
GROUP  BY table_schema;

GitHub - failed to connect to github 443 windows/ Failed to connect to gitHub - No Error

If your country or working environment blocks sites like Github.

Then you can build a proxy, e.g. use xxnet, which is free & based on Google's GAE, and available for Windows / Linux / Mac.

Then set proxy address for git, e.g:

git config --global http.proxy 127.0.0.1:8087

How to log PostgreSQL queries?

You also need add these lines in PostgreSQL and restart the server:

log_directory = 'pg_log'                    
log_filename = 'postgresql-dateformat.log'
log_statement = 'all'
logging_collector = on

How do I set ANDROID_SDK_HOME environment variable?

from command prompt:

set ANDROID_SDK_HOME=C:\[wherever your sdk folder is]

should do the trick.

HowTo Generate List of SQL Server Jobs and their owners

It's better to use SUSER_SNAME() since when there is no corresponding login on the server the join to syslogins will not match

SELECT  s.name ,
        SUSER_SNAME(s.owner_sid) AS owner
FROM    msdb..sysjobs s 
ORDER BY name

dyld: Library not loaded: /usr/local/lib/libpng16.16.dylib with anything php related

I got this problem after updating MAMP, and the custom $PATH I had set was wrong because of the new php version, so the wrong version of php was loaded first, and it was that version of php that triggered the error.

Updating the path in my .bash_profile fixed my issue.

How to remove a TFS Workspace Mapping?

The error is genuine. You might have created workspace with same name on different machine. Now you may have changed machine having different machine name.

So here is work-around that will definitely work.Following is work-around.

  1. Go to "Team-Explorer"
  2. Go to "Source-Control"
  3. Go to Workspace drop-down
  4. Click on "Workspaces..."
  5. A pop-up window will appear
  6. Click on "Show remote workspaces"
  7. Now delete the workspace which is conflicting and you can proceed your work.

Turning off some legends in a ggplot

You can use guide=FALSE in scale_..._...() to suppress legend.

For your example you should use scale_colour_continuous() because length is continuous variable (not discrete).

(p3 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +
   scale_colour_continuous(guide = FALSE) +
   geom_point()
)

Or using function guides() you should set FALSE for that element/aesthetic that you don't want to appear as legend, for example, fill, shape, colour.

p0 <- ggplot(mov, aes(year, rating, colour = length, shape = mpaa)) +
  geom_point()    
p0+guides(colour=FALSE)

UPDATE

Both provided solutions work in new ggplot2 version 2.0.0 but movies dataset is no longer present in this library. Instead you have to use new package ggplot2movies to check those solutions.

library(ggplot2movies)
data(movies)
mov <- subset(movies, length != "")

Tell Ruby Program to Wait some amount of time

I find until very useful with sleep. example:

> time = Time.now
> sleep 2.seconds until Time.now > time + 10.seconds # breaks when true
# or something like
> sleep 1.seconds until !req.loading # suggested by ohsully

How do I create a folder in VB if it doesn't exist?

 
If Not Directory.Exists(somePath) then
    Directory.CreateDirectory(somePath)
End If

How to round the double value to 2 decimal points?

 
double RoundTo2Decimals(double val) {
            DecimalFormat df2 = new DecimalFormat("###.##");
        return Double.valueOf(df2.format(val));
}

JavaScript: Global variables after Ajax requests

The reason your code fails is because post() will start an asynchronous request to the server. What that means for you is that post() returns immediately, not after the request completes, like you are expecting.

What you need, then, is for the request to be synchronous and block the current thread until the request completes. Thus,

var it_works = false;

$.ajax({
  url: 'some_file.php',
  async: false,  # makes request synchronous
  success: function() {
    it_works = true;
  }
});

alert(it_works);

Java equivalent to #region in C#

With Android Studio, try this:

//region VARIABLES
private String _sMyVar1;
private String _sMyVar2;
//endregion

Careful : no blank line after //region ...

And you will get:

Java Multithreading concept and join() method

I came across the join() while learning about race condition and I will clear the doubts I was having. So let us take this small example 

Thread t2 = new Thread(
             new Runnable() {
                 public void run () {
                     //do something
                 }
              }
);
Thread t1 = new Thread(
             new Runnable() {
                 public void run () {
                     //do something
                 }
              }
);
t2.start(); //Line 11
t1.start(); //Line 12
t2.join();  //Line 13
t1.join();  //Line 14
System.out.print("<Want to print something that was being modified by t2 and t1>")

My AIM
Three threads are running namely t1, t2 and the main thread. I want to print something after the t1 and t2 has finished. The printing operation is on my main thread therefore for the expected answer I need to let t1 and t2 finish and then print my output.

So t1.join() just makes the main thread wait, till the t1 thread completes before going to the next line in program.

Here is the definition as per GeeksforGeeks:

java.lang.Thread class provides the join() method which allows one thread to wait until another thread completes its execution.

Here is one question that might solve your doubt

Q-> Will t1 thread get the time slice to run by the thread scheduler, when the program is processing the t2.join() at Line 13?

ANS-> Yes it will be eligible to get the time slice to run as we have already made it eligible by running the line t1.start() at Line 11.
t2.join() only applies the condition when the JVM will go to next line, that is Line 14.
It might be also possible that t1 might get finished processing at Line 13.

When to use async false and async true in ajax function in jquery

It is best practice to go asynchronous if you can do several things in parallel (no inter-dependencies). If you need it to complete to continue loading the next thing you could use synchronous, but note that this option is deprecated to avoid abuse of sync:

jQuery.ajax() method's async option deprecated, what now?

Calculating distance between two points, using latitude longitude?

Here is a page with javascript examples for various spherical calculations. The very first one on the page should give you what you need.

http://www.movable-type.co.uk/scripts/latlong.html

Here is the Javascript code

var R = 6371; // km
var dLat = (lat2-lat1).toRad();
var dLon = (lon2-lon1).toRad(); 
var a = Math.sin(dLat/2) * Math.sin(dLat/2) + 
        Math.cos(lat1.toRad()) * Math.cos(lat2.toRad()) *
        Math.sin(dLon/2) * Math.sin(dLon/2); 
var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a)); 
var d = R * c;

Where 'd' will hold the distance.

Select default option value from typescript angular 6

i manage this by doing like this =>

<select class="form-control" 
        [(ngModel)]="currentUserID"
        formControlName="users">
        <option value='-1'>{{"select a user" | translate}}</option>
            <option 
            *ngFor="let user of users"
            value="{{user.id}}">
            {{user.firstname}}
   </option>
</select>

Python vs. Java performance (runtime speed)

If you ignore the characteristics of both languages, how do you define "SPEED"? Which features should be in your benchmark and which do you want to omit?

For example:

  • Does it count when Java executes an empty loop faster than Python?
  • Or is Python faster when it notices that the loop body is empty, the loop header has no side effects and it optimizes the whole loop away?
  • Or is that "a language characteristic"?
  • Do you want to know how many bytecodes each language can execute per second?
  • Which ones? Only the fast ones or all of them?
  • How do you count the Java VM JIT compiler which turns bytecode into CPU-specific assembler code at runtime?
  • Do you include code compilation times (which are extra in Java but always included in Python)?

Conclusion: Your question has no answer because it isn't defined what you want. Even if you made it more clear, the question will probably become academic since you will measure something that doesn't count in real life. For all of my projects, both Java and Python have always been fast enough. Of course, I would prefer one language over the other for a specific problem in a certain context.

In AVD emulator how to see sdcard folder? and Install apk to AVD?

I have used the following procedure.

Procedure to install the apk files in Android Emulator(AVD):

Check your installed directory(ex: C:\Program Files (x86)\Android\android-sdk\platform-tools), whether it has the adb.exe or not). If not present in this folder, then download the attachment here, extract the zip files. You will get adb files, copy and paste those three files inside tools folder

Run AVD manager from C:\Program Files (x86)\Android\android-sdk and start the Android Emulator.

Copy and paste the apk file inside the C:\Program Files (x86)\Android\android-sdk\platform-tools

  • Go to Start -> Run -> cmd

  • Type cd “C:\Program Files (x86)\Android\android-sdk\platform-tools”

  • Type adb install example.apk

  • After getting success command

  • Go to Application icon in Android emulator, we can see the your application

How can I convert a DOM element to a jQuery element?

 
var elm = document.createElement("div");
var jelm = $(elm);//convert to jQuery Element
var htmlElm = jelm[0];//convert to HTML Element

Way to read first few lines for pandas dataframe

I think you can use the nrows parameter. From the docs:

nrows : int, default None

    Number of rows of file to read. Useful for reading pieces of large files

which seems to work. Using one of the standard large test files (988504479 bytes, 5344499 lines):

In [1]: import pandas as pd

In [2]: time z = pd.read_csv("P00000001-ALL.csv", nrows=20)
CPU times: user 0.00 s, sys: 0.00 s, total: 0.00 s
Wall time: 0.00 s

In [3]: len(z)
Out[3]: 20

In [4]: time z = pd.read_csv("P00000001-ALL.csv")
CPU times: user 27.63 s, sys: 1.92 s, total: 29.55 s
Wall time: 30.23 s

Set value for particular cell in pandas DataFrame with iloc

To modify the value in a cell at the intersection of row "r" (in column "A") and column "C"

  1. retrieve the index of the row "r" in column "A"

        i = df[ df['A']=='r' ].index.values[0]

  2. modify the value in the desired column "C"

        df.loc[i,"C"]="newValue"

Note: before, be sure to reset the index of rows ...to have a nice index list!

        df=df.reset_index(drop=True)

How do I use an image as a submit button?

HTML:

<button type="submit" name="submit" class="button">
  <img src="images/free.png" />
</button>

CSS:

.button {  }

Convert int to ASCII and back in Python

ASCII to int:

ord('a')

gives 97

And back to a string:

  • in Python2: str(unichr(97))
  • in Python3: chr(97)

gives 'a'

Onclick javascript to make browser go back to previous page?

This is the only thing that works on all current browsers:

<script>
function goBack() {
    history.go(-1);
}
</script>
<button onclick="goBack()">Go Back</button>

SVN checkout the contents of a folder, not the folder itself

 
svn co svn://path destination

To specify current directory, use a "." for your destination directory:

svn checkout file:///home/landonwinters/svn/waterproject/trunk .

Bad Gateway 502 error with Apache mod_proxy and Tomcat

you should be able to get this problem resolved through a timeout and proxyTimeout parameter set to 600 seconds. It worked for me after battling for a while.

Log to the base 2 in python

http://en.wikipedia.org/wiki/Binary_logarithm

def lg(x, tol=1e-13):
  res = 0.0

  # Integer part
  while x<1:
    res -= 1
    x *= 2
  while x>=2:
    res += 1
    x /= 2

  # Fractional part
  fp = 1.0
  while fp>=tol:
    fp /= 2
    x *= x
    if x >= 2:
        x /= 2
        res += fp

  return res

How do I compare a value to a backslash?

Try like this:

if message.value[0] == "/" or message.value[0] == "\\":
  do_stuff

Uncaught TypeError: undefined is not a function on loading jquery-min.js

Remember: Javascript functions are CASE SENSITIVE.

I had a case where I'm pretty sure that my code would run smoothly. But still, got an error and I checked the Javascript console of Google Chrome to check what it is.

My error line is

opt.SetAttribute("value",values[a]);

And got the same error message:

Uncaught TypeError: undefined is not a function

Nothing seems wrong with the code above but it was not running. I troubleshoot for almost an hour and then compared it with my other running code. My error is that it was set to SetAttribute, which should be setAttribute.

Select Top and Last rows in a table (SQL server)

You must sort your data according your needs (es. in reverse order) and use select top query

How to use ScrollView in Android?

To scroll data in text view you can use this to your text view. and add and for anything other layout you can just add scroll view on layout as people are saying above.

/** android:scrollable=true at textview in xml layout.

TextView txtScroll = (TextView) findViewById(R.id.txt1);
        txtScroll.setMovementMethod(new ScrollingMovementMethod());

*//

How to visualize an XML schema?

If someone works with IBM Rational Application Developer then XSD browser is built in it.

How to get the list of all installed color schemes in Vim?

If you are willing to install a plugin, I recommend https://github.com/vim-scripts/CycleColor.

to cycle through all installed colorschemes. Nice way to easily choose a colorscheme.

How to print current date on python3?

I use this which is standard for every time

import datetime
now = datetime.datetime.now()
print ("Current date and time : ")
print (now.strftime("%Y-%m-%d %H:%M:%S"))

Android app unable to start activity componentinfo

The question is answered already, but I want add more information about the causes.

Android app unable to start activity componentinfo

This error often comes with appropriate logs. You can read logs and can solve this issue easily.

Here is a sample log. In which you can see clearly ClassCastException. So this issue came because TextView cannot be cast to EditText.

Caused by: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText

11-04 01:24:10.403: D/AndroidRuntime(1050): Shutting down VM
11-04 01:24:10.403: W/dalvikvm(1050): threadid=1: thread exiting with uncaught exception (group=0x41465700)
11-04 01:24:10.543: E/AndroidRuntime(1050): FATAL EXCEPTION: main
11-04 01:24:10.543: E/AndroidRuntime(1050): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.troysantry.tipcalculator/com.troysantry.tipcalculator.TipCalc}: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.os.Looper.loop(Looper.java:137)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread.main(ActivityThread.java:5103)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at java.lang.reflect.Method.invokeNative(Native Method)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at java.lang.reflect.Method.invoke(Method.java:525)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at dalvik.system.NativeStart.main(Native Method)
11-04 01:24:10.543: E/AndroidRuntime(1050): Caused by: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 01:24:10.543: E/AndroidRuntime(1050):     at com.troysantry.tipcalculator.TipCalc.onCreate(TipCalc.java:45)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.Activity.performCreate(Activity.java:5133)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
11-04 01:24:10.543: E/AndroidRuntime(1050):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
11-04 01:24:10.543: E/AndroidRuntime(1050):     ... 11 more
11-04 01:29:11.177: I/Process(1050): Sending signal. PID: 1050 SIG: 9
11-04 01:31:32.080: D/AndroidRuntime(1109): Shutting down VM
11-04 01:31:32.080: W/dalvikvm(1109): threadid=1: thread exiting with uncaught exception (group=0x41465700)
11-04 01:31:32.194: E/AndroidRuntime(1109): FATAL EXCEPTION: main
11-04 01:31:32.194: E/AndroidRuntime(1109): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.troysantry.tipcalculator/com.troysantry.tipcalculator.TipCalc}: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.os.Looper.loop(Looper.java:137)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread.main(ActivityThread.java:5103)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at java.lang.reflect.Method.invokeNative(Native Method)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at java.lang.reflect.Method.invoke(Method.java:525)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at dalvik.system.NativeStart.main(Native Method)
11-04 01:31:32.194: E/AndroidRuntime(1109): Caused by: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 01:31:32.194: E/AndroidRuntime(1109):     at com.troysantry.tipcalculator.TipCalc.onCreate(TipCalc.java:44)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.Activity.performCreate(Activity.java:5133)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
11-04 01:31:32.194: E/AndroidRuntime(1109):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
11-04 01:31:32.194: E/AndroidRuntime(1109):     ... 11 more
11-04 01:36:33.195: I/Process(1109): Sending signal. PID: 1109 SIG: 9
11-04 02:11:09.684: D/AndroidRuntime(1167): Shutting down VM
11-04 02:11:09.684: W/dalvikvm(1167): threadid=1: thread exiting with uncaught exception (group=0x41465700)
11-04 02:11:09.855: E/AndroidRuntime(1167): FATAL EXCEPTION: main
11-04 02:11:09.855: E/AndroidRuntime(1167): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.troysantry.tipcalculator/com.troysantry.tipcalculator.TipCalc}: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2211)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2261)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1256)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.os.Looper.loop(Looper.java:137)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread.main(ActivityThread.java:5103)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at java.lang.reflect.Method.invokeNative(Native Method)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at java.lang.reflect.Method.invoke(Method.java:525)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at dalvik.system.NativeStart.main(Native Method)
11-04 02:11:09.855: E/AndroidRuntime(1167): Caused by: java.lang.ClassCastException: android.widget.TextView cannot be cast to android.widget.EditText
11-04 02:11:09.855: E/AndroidRuntime(1167):     at com.troysantry.tipcalculator.TipCalc.onCreate(TipCalc.java:44)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.Activity.performCreate(Activity.java:5133)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
11-04 02:11:09.855: E/AndroidRuntime(1167):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2175)
11-04 02:11:09.855: E/AndroidRuntime(1167):     ... 11 more

Some Common Mistakes.

1.findViewById() of non existing view

Like when you use findViewById(R.id.button) when button id does not exist in layout XML.

2. Wrong cast.

If you wrong cast some class, then you get this error. Like you cast RelativeLayout to LinearLayout or EditText to TextView.

3. Activity not registered in manifest.xml

If you did not register Activity in manifest.xml then this error comes.

4. findViewById() with declaration at top level

Below code is incorrect. This will create error. Because you should do findViewById() after calling setContentView(). Because an View can be there after it is created.

public class MainActivity extends Activity {

  ImageView mainImage = (ImageView) findViewById(R.id.imageViewMain); //incorrect way

  @Override
  protected void onCreate(Bundle savedInstanceState){
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    mainImage = (ImageView) findViewById(R.id.imageViewMain); //correct way
    //...
  }
}

5. Starting abstract Activity class.

When you try to start an Activity which is abstract, you will will get this error. So just remove abstract keyword before activity class name.

6. Using kotlin but kotlin not configured.

If your activity is written in Kotlin and you have not setup kotlin in your app. then you will get error. You can follow simple steps as written in Android Link or Kotlin Link. You can check this answer too.

More information

Read about Downcast and Upcast

Read about findViewById() method of Activity class

Super keyword in Java

How to register activity in manifest

How to change the color of text in javafx TextField?

The CSS styles for text input controls such as TextField for JavaFX 8 are defined in the modena.css stylesheet as below. Create a custom CSS stylesheet and modify the colors as you wish. Use the CSS reference guide if you need help understanding the syntax and available attributes and values.

.text-input {
    -fx-text-fill: -fx-text-inner-color;
    -fx-highlight-fill: derive(-fx-control-inner-background,-20%);
    -fx-highlight-text-fill: -fx-text-inner-color;
    -fx-prompt-text-fill: derive(-fx-control-inner-background,-30%);
    -fx-background-color: linear-gradient(to bottom, derive(-fx-text-box-border, -10%), -fx-text-box-border),
        linear-gradient(from 0px 0px to 0px 5px, derive(-fx-control-inner-background, -9%), -fx-control-inner-background);
    -fx-background-insets: 0, 1;
    -fx-background-radius: 3, 2;
    -fx-cursor: text;
    -fx-padding: 0.333333em 0.583em 0.333333em 0.583em; /* 4 7 4 7 */
}
.text-input:focused {
    -fx-highlight-fill: -fx-accent;
    -fx-highlight-text-fill: white;
    -fx-background-color: 
        -fx-focus-color,
        -fx-control-inner-background,
        -fx-faint-focus-color,
        linear-gradient(from 0px 0px to 0px 5px, derive(-fx-control-inner-background, -9%), -fx-control-inner-background);
    -fx-background-insets: -0.2, 1, -1.4, 3;
    -fx-background-radius: 3, 2, 4, 0;
    -fx-prompt-text-fill: transparent;
}

Although using an external stylesheet is a preferred way to do the styling, you can style inline, using something like below:

textField.setStyle("-fx-text-inner-color: red;");