Programs & Examples On #Chop

Android Material and appcompat Manifest merger failed

  1. Please go to Refactor->Migrate->Migrate to Android X.

  2. Please add this to your gradle.properties file:

    android.enableJetifier=true
    android.useAndroidX=true
    

And perform Sync.

JS map return object

map rockets and add 10 to its launches:

_x000D_
_x000D_
var rockets = [_x000D_
    { country:'Russia', launches:32 },_x000D_
    { country:'US', launches:23 },_x000D_
    { country:'China', launches:16 },_x000D_
    { country:'Europe(ESA)', launches:7 },_x000D_
    { country:'India', launches:4 },_x000D_
    { country:'Japan', launches:3 }_x000D_
];_x000D_
rockets.map((itm) => {_x000D_
    itm.launches += 10_x000D_
    return itm_x000D_
})_x000D_
console.log(rockets)
_x000D_
_x000D_
_x000D_

If you don't want to modify rockets you can do:

var plusTen = []
rockets.forEach((itm) => {
    plusTen.push({'country': itm.country, 'launches': itm.launches + 10})
})

Invalid configuration object. Webpack has been initialised using a configuration object that does not match the API schema

I guess your webpack version is 2.2.1. I think you should be using this Migration Guide --> https://webpack.js.org/guides/migrating/

Also, You can use this example of TypeSCript + Webpack 2.

Consider marking event handler as 'passive' to make the page more responsive

Also encounter this in select2 dropdown plugin in Laravel. Changing the value as suggested by Alfred Wallace from

this.element.addEventListener(t, e, !1)

to

this.element.addEventListener(t, e, { passive: true} )

solves the issue. Why he has a down vote, I don't know but it works for me.

Python pandas: how to specify data types when reading an Excel file?

If your key has a fixed number of digits, you should probably store as text rather than as numeric data. You can use the converters argument or read_excel for this.

Or, if this does not work, just manipulate your data once it's read into your dataframe:

df['key_zfill'] = df['key'].astype(str).str.zfill(4)

  names   key key_zfill
0   abc     5      0005
1   def  4962      4962
2   ghi   300      0300
3   jkl    14      0014
4   mno    20      0020

How to add users to Docker container?

Adding user in docker and running your app under that user is very good practice for security point of view. To do that I would recommend below steps:

FROM node:10-alpine

# Copy source to container
RUN mkdir -p /usr/app/src

# Copy source code
COPY src /usr/app/src
COPY package.json /usr/app
COPY package-lock.json /usr/app

WORKDIR /usr/app

# Running npm install for production purpose will not run dev dependencies.
RUN npm install -only=production    

# Create a user group 'xyzgroup'
RUN addgroup -S xyzgroup

# Create a user 'appuser' under 'xyzgroup'
RUN adduser -S -D -h /usr/app/src appuser xyzgroup

# Chown all the files to the app user.
RUN chown -R appuser:xyzgroup /usr/app

# Switch to 'appuser'
USER appuser

# Open the mapped port
EXPOSE 3000

# Start the process
CMD ["npm", "start"]

Above steps is a full example of the copying NodeJS project files, creating a user group and user, assigning permissions to the user for the project folder, switching to the newly created user and running the app under that user.

Solve Cross Origin Resource Sharing with Flask

I struggled a lot with something similar. Try the following:

  1. Use some sort of browser plugin which can display the HTML headers.
  2. Enter the URL to your service, and view the returned header values.
  3. Make sure Access-Control-Allow-Origin is set to one and only one domain, which should be the request origin. Do not set Access-Control-Allow-Origin to *.

If this doesn't help, take a look at this article. It's on PHP, but it describes exactly which headers must be set to which values for CORS to work.

CORS That Works In IE, Firefox, Chrome And Safari

set initial viewcontroller in appdelegate - swift

iOS 13+

In the SceneDelegate:

var window: UIWindow?

func scene(_ scene: UIScene, willConnectTo session: UISceneSession, options 
connectionOptions: UIScene.ConnectionOptions) {
    guard let windowScene = (scene as? UIWindowScene) else { return }
    window = UIWindow(windowScene: windowScene)
    let vc = UIViewController() //Instead of UIViewController() we initilise our initial viewController
    window?.rootViewController = vc
    window?.makeKeyAndVisible()
}

How do I hide the status bar in a Swift iOS app?

A solution that works for me; if you want to hide the status bar on a specific view controller while loading:

import UIKit

class ViewController: UIViewController {

private var hideStatusBar: Bool = false

override var prefersStatusBarHidden: Bool {
    return hideStatusBar
}

override var preferredStatusBarUpdateAnimation: UIStatusBarAnimation {
    return UIStatusBarAnimation.slide
}

override func viewDidLoad() {
    super.viewDidLoad()

    view.backgroundcolor = .white
    hideStatusBar = true

    UIView.animate(withDuration: 0.3) {
        self.setNeedsStatusBarAppearanceUpdate()
    }
}

Attention: if you set the key "View controller-based status bar appearance" to "NO" in your info.plist the code above doesn't work. You should set the key to "YES" or remove it from info.plist

"Could not find a part of the path" error message

Is the drive E a mapped drive? Then, it can be created by another account other than the user account. This may be the cause of the error.

ImportError: numpy.core.multiarray failed to import

In my case this problem was because I'd two python installations (2.7 and 3.5) and pip was installing numpy in the 3.5 python directory only, irrespective of which pip version I used.

I solved the problem by explicitly specifying the target install directory as such:

pip install --target c:\apps\python-2.7\Lib\site-packages numpy

Get current time in hours and minutes

With bash version >= 4.2:

printf "%(%H:%M)T\n"

or

printf -v foo "%(%H:%M)T\n"
echo "$foo"

See: man bash

Controlling fps with requestAnimationFrame?

For throttling FPS to any value, pls see jdmayfields answer. However, for a very quick and easy solution to halve your frame rate, you can simply do your computations only every 2nd frame by:

requestAnimationFrame(render);
function render() {
  // ... computations ...
  requestAnimationFrame(skipFrame);
}
function skipFrame() { requestAnimationFrame(render); }

Similarly you could always call render but use a variable to control whether you do computations this time or not, allowing you to also cut FPS to a third or fourth (in my case, for a schematic webgl-animation 20fps is still enough while considerably lowering computational load on the clients)

Detect if the app was launched/opened from a push notification

M.Othman's answer is correct for apps that don't contain scene delegate For Scene Delegate Apps This worked for me on iOS 13

Here is the code for that should be written in will connect scene

if connectionOptions.notificationResponse == nil { 
//Not opened from push notification
} else {
  //Opened from push notification
}

Code for app delegate to support earlier versions didFinishLaunchingWithOptions

let notification = launchOptions?[UIApplication.LaunchOptionsKey.remoteNotification]
        if (notification != nil) {

            //Launched from push notification
        } else {

            //Launch from other source
        }

Linq filter List<string> where it contains a string value from another List<string>

its even easier:

fileList.Where(item => filterList.Contains(item))

in case you want to filter not for an exact match but for a "contains" you can use this expression:

var t = fileList.Where(file => filterList.Any(folder => file.ToUpperInvariant().Contains(folder.ToUpperInvariant())));

Launch iOS simulator from Xcode and getting a black screen, followed by Xcode hanging and unable to stop tasks

I was doing what doug suggests ("Reset Content and Settings") which works but takes a lot of time and it is really annoying... until I recently found completely accidental another solution that is much quicker and seems to also work so far! Just hit cmd+L on your simulator or go to the simulator menu "Hardware -> Lock", which locks the screen, when you unlock the screen the app works like nothing ever happened :)

Error HRESULT E_FAIL has been returned from a call to a COM component VS2012 when debugging

I have been getting this a lot lately. I've been having to create a new file and move the code to the new file to get around it.

I fixed it by deleting the solution's suo file (as far as I can tell, it just stores info like what files are open in the IDE and stuff, and deleting it does no real damage).

My file was seemingly corrupt. (The IDE wouldn't remember what files were open when restarting. It was 1.7MB in size, which seems large, even for my 40 project solution, which rarely has more than 50 files open at once.)

Edit: I just recently had to do this in VS2017 but for another reason, it was taking longer to build and took 5+ minutes to stop a debug session, deleting that pesky suo file fixed it right up, now anytime VS acts weird deleting SUO is my first port of call.

Directory.GetFiles of certain extension

If you would like to do your filtering in LINQ, you can do it like this:

var ext = new List<string> { "jpg", "gif", "png" };
var myFiles = Directory
    .EnumerateFiles(dir, "*.*", SearchOption.AllDirectories)
    .Where(s => ext.Contains(Path.GetExtension(s).TrimStart(".").ToLowerInvariant()));

Now ext contains a list of allowed extensions; you can add or remove items from it as necessary for flexible filtering.

NSInternalInconsistencyException', reason: 'Could not load NIB in bundle: 'NSBundle

I spend a hour finding out what was wrong.. But Clean Project did the trick.

Build -> Clean All

The accepted solution is probably also working.. but this was enough for me.

Right pad a string with variable number of spaces

Whammo blammo (for leading spaces):

SELECT 
    RIGHT(space(60) + cust_name, 60),
    RIGHT(space(60) + cust_address, 60)

OR (for trailing spaces)

SELECT
    LEFT(cust_name + space(60), 60),
    LEFT(cust_address + space(60), 60),

Twitter Bootstrap: div in container with 100% height

you need to add padding-top to "fill" element, plus add box-sizing:border-box - sample here bootply

iPad Safari scrolling causes HTML elements to disappear and reappear with a delay

Targeting all elements but html : *:not(html) caused problems on other elements in my case. It modified the stacking context, causing some z-index to break.

We should better try to target the right element and apply -webkit-transform: translate3d(0,0,0) to it only.

Edit : sometimes the translate3D(0,0,0) doesn't work, we can use the following method, targeting the right element :

@keyframes redraw{
    0% {opacity: 1;}
    100% {opacity: .99;}
}

// ios redraw fix
animation: redraw 1s linear infinite;

Xcode error - Thread 1: signal SIGABRT

You are trying to load a XIB named DetailViewController, but no such XIB exists or it's not member of your current target.

CSS transition when class removed

The @jfriend00's answer helps me to understand the technique to animate only remove class (not add).

A "base" class should have transition property (like transition: 2s linear all;). This enables animations when any other class is added or removed on this element. But to disable animation when other class is added (and only animate class removing) we need to add transition: none; to the second class.

Example

CSS:

.issue {
  background-color: lightblue;
  transition: 2s linear all;
}

.recently-updated {
  background-color: yellow;
  transition: none;
}

HTML:

<div class="issue" onclick="addClass()">click me</div>

JS (only needed to add class):

var timeout = null;

function addClass() {
  $('.issue').addClass('recently-updated');
  if (timeout) {
    clearTimeout(timeout);
    timeout = null;
  }
  timeout = setTimeout(function () {
    $('.issue').removeClass('recently-updated');
  }, 1000);
}

plunker of this example.

With this code only removing of recently-updated class will be animated.

Get device token for push notification

In order to get the device token use following code but you can get the device token only using physical device. If you have mandatory to send the device token then while using simulator you can put the below condition.

  if(!(TARGET_IPHONE_SIMULATOR))
    {
        [infoDict setValue:[[NSUserDefaults standardUserDefaults] valueForKey:@"DeviceToken"] forKey:@"device_id"];
    }
    else
    {
        [infoDict setValue:@"e79c2b66222a956ce04625b22e3cad3a63e91f34b1a21213a458fadb2b459385" forKey:@"device_id"];
    }



- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken
{
    NSLog(@"My token is: %@", deviceToken);
    NSString * deviceTokenString = [[[[deviceToken description] stringByReplacingOccurrencesOfString: @"<" withString: @""] stringByReplacingOccurrencesOfString: @">" withString: @""]   stringByReplacingOccurrencesOfString: @" " withString: @""];
    NSLog(@"the generated device token string is : %@",deviceTokenString);
    [[NSUserDefaults standardUserDefaults] setObject:deviceTokenString forKey:@"DeviceToken"];
}

iOS application: how to clear notifications?

Maybe in case there are scheduled alarms and uncleared app icon badges.

NSArray *scheduledLocalNotifications = [application scheduledLocalNotifications];
NSInteger applicationIconBadgeNumber = [application applicationIconBadgeNumber];

[application cancelAllLocalNotifications];
[application setApplicationIconBadgeNumber:0];

for (UILocalNotification* scheduledLocalNotification in scheduledLocalNotifications) {
    [application scheduleLocalNotification:scheduledLocalNotification];
}
[application setApplicationIconBadgeNumber:applicationIconBadgeNumber];

Limiting the number of characters in a string, and chopping off the rest

Ideally you should try not to modify the internal data representation for the purpose of creating the table. Whats the problem with String.format()? It will return you new string with required width.

Applications are expected to have a root view controller at the end of application launch

I had the same error message because I called an alert in

- (void)applicationDidBecomeActive:(UIApplication *)application 

instead of

- (void)applicationWillEnterForeground:(UIApplication *)application

How to edit HTML input value colour?

Please try this:

<input class="col-xs-12 col-sm-8 col-sm-offset-2 col-md-8 col-md-offset-2" type="text" name="name" value="" placeholder="Your Name" style="background-color:blue;"/>

You basically put all the CSS inside the style part of the input tag and it works.

how to read a text file using scanner in Java?

Just another thing... Instead of System.out.println("Error Message Here"), use System.err.println("Error Message Here"). This will allow you to distinguish the differences between errors and normal code functioning by displaying the errors(i.e. everything inside System.err.println()) in red.

NOTE: It also works when used with System.err.print("Error Message Here")

Get all files and directories in specific path fast

(copied this piece from my other answer in your other question)

Show progress when searching all files in a directory

Fast files enumeration

Of course, as you already know, there are a lot of ways of doing the enumeration itself... but none will be instantaneous. You could try using the USN Journal of the file system to do the scan. Take a look at this project in CodePlex: MFT Scanner in VB.NET... it found all the files in my IDE SATA (not SSD) drive in less than 15 seconds, and found 311000 files.

You will have to filter the files by path, so that only the files inside the path you are looking are returned. But that is the easy part of the job!

curl_init() function not working

function curl_int(); cause server error,install sudo apt-get install php5-curl restart apache2 server .. it will work like charm

Simple and fast method to compare images for similarity

I face the same issues recently, to solve this problem(simple and fast algorithm to compare two images) once and for all, I contribute an img_hash module to opencv_contrib, you can find the details from this link.

img_hash module provide six image hash algorithms, quite easy to use.

Codes example

origin lenaorigin lena

blur lenablur lena

resize lenaresize lena

shift lenashift lena

#include <opencv2/core.hpp>
#include <opencv2/core/ocl.hpp>
#include <opencv2/highgui.hpp>
#include <opencv2/img_hash.hpp>
#include <opencv2/imgproc.hpp>

#include <iostream>

void compute(cv::Ptr<cv::img_hash::ImgHashBase> algo)
{
    auto input = cv::imread("lena.png");
    cv::Mat similar_img;

    //detect similiar image after blur attack
    cv::GaussianBlur(input, similar_img, {7,7}, 2, 2);
    cv::imwrite("lena_blur.png", similar_img);
    cv::Mat hash_input, hash_similar;
    algo->compute(input, hash_input);
    algo->compute(similar_img, hash_similar);
    std::cout<<"gaussian blur attack : "<<
               algo->compare(hash_input, hash_similar)<<std::endl;

    //detect similar image after shift attack
    similar_img.setTo(0);
    input(cv::Rect(0,10, input.cols,input.rows-10)).
            copyTo(similar_img(cv::Rect(0,0,input.cols,input.rows-10)));
    cv::imwrite("lena_shift.png", similar_img);
    algo->compute(similar_img, hash_similar);
    std::cout<<"shift attack : "<<
               algo->compare(hash_input, hash_similar)<<std::endl;

    //detect similar image after resize
    cv::resize(input, similar_img, {120, 40});
    cv::imwrite("lena_resize.png", similar_img);
    algo->compute(similar_img, hash_similar);
    std::cout<<"resize attack : "<<
               algo->compare(hash_input, hash_similar)<<std::endl;
}

int main()
{
    using namespace cv::img_hash;

    //disable opencl acceleration may(or may not) boost up speed of img_hash
    cv::ocl::setUseOpenCL(false);

    //if the value after compare <= 8, that means the images
    //very similar to each other
    compute(ColorMomentHash::create());

    //there are other algorithms you can try out
    //every algorithms have their pros and cons
    compute(AverageHash::create());
    compute(PHash::create());
    compute(MarrHildrethHash::create());
    compute(RadialVarianceHash::create());
    //BlockMeanHash support mode 0 and mode 1, they associate to
    //mode 1 and mode 2 of PHash library
    compute(BlockMeanHash::create(0));
    compute(BlockMeanHash::create(1));
}

In this case, ColorMomentHash give us best result

  • gaussian blur attack : 0.567521
  • shift attack : 0.229728
  • resize attack : 0.229358

Pros and cons of each algorithm

Performance under different attacks

The performance of img_hash is good too

Speed comparison with PHash library(100 images from ukbench) compute performance comparison performance

If you want to know the recommend thresholds for these algorithms, please check this post(http://qtandopencv.blogspot.my/2016/06/introduction-to-image-hash-module-of.html). If you are interesting about how do I measure the performance of img_hash modules(include speed and different attacks), please check this link(http://qtandopencv.blogspot.my/2016/06/speed-up-image-hashing-of-opencvimghash.html).

How to write the code for the back button?

If you want to do it (what I think you are trying right now) then replace this line

<input type="submit" <a href="#" onclick="history.back();">"Back"</a>

with this

<button type="button" onclick="history.back();">Back</button>

If you don't want to rely on JavaScript then you could get the HTTP_REFERER variable an then provide it in a link like this:

<a href="<?php echo $_SERVER['HTTP_REFERER'] ?>">Back</a>

Viewing full output of PS command

It is likely that you're using a pager such as less or most since the output of ps aux is longer than a screenful. If so, the following options will cause (or force) long lines to wrap instead of being truncated.

ps aux | less -+S

ps aux | most -w

If you use either of the following commands, lines won't be wrapped but you can use your arrow keys or other movement keys to scroll left and right.

ps aux | less -S    # use arrow keys, or Esc-( and Esc-), or Alt-( and Alt-) 

ps aux | most       # use arrow keys, or < and > (Tab can also be used to scroll right)

Lines are always wrapped for more and pg.

When ps aux is used in a pipe, the w option is unnecessary since ps only uses screen width when output is to the terminal.

Escape quotes in JavaScript

&quot; would work in this particular case, as suggested before me, because of the HTML context.

However, if you want your JavaScript code to be independently escaped for any context, you could opt for the native JavaScript encoding:
' becomes \x27
" becomes \x22

So your onclick would become:
DoEdit('Preliminary Assessment \x22Mini\x22');

This would work for example also when passing a JavaScript string as a parameter to another JavaScript method (alert() is an easy test method for this).

I am referring you to the duplicate Stack Overflow question, How do I escape a string inside JavaScript code inside an onClick handler?.

How can I get my webapp's base URL in ASP.NET MVC?

The following worked solidly for me

var request = HttpContext.Request;
                        var appUrl = System.Web.HttpRuntime.AppDomainAppVirtualPath;

                        if (appUrl != "/")
                            appUrl = "/" + appUrl + "/";

                        var newUrl = string.Format("{0}://{1}{2}{3}/{4}", request.Url.Scheme, request.UrlReferrer.Host, appUrl, "Controller", "Action");

How to call a Web Service Method?

James' answer is correct, of course, but I should remind you that the whole ASMX thing is, if not obsolete, at least not the current method. I strongly suggest that you look into WCF, if only to avoid learning things you will need to forget.

JavaScript chop/slice/trim off last character in string

You can, in fact, remove the last arr.length - 2 items of an array using arr.length = 2, which if the array length was 5, would remove the last 3 items.

Sadly, this does not work for strings, but we can use split() to split the string, and then join() to join the string after we've made any modifications.

_x000D_
_x000D_
var str = 'string'

String.prototype.removeLast = function(n) {
  var string = this.split('')
  string.length = string.length - n

  return string.join('')
}

console.log(str.removeLast(3))
_x000D_
_x000D_
_x000D_

CSS Printing: Avoiding cut-in-half DIVs between pages?

Using break-inside should work:

@media print {
  div {
    break-inside: avoid;
  }
}

It works on all major browsers:

  • Chrome 50+
  • Edge 12+
  • Firefox 65+
  • Opera 37+
  • Safari 10+

Using page-break-inside: avoid; instead should work too, but has been exactly deprecated by break-inside: avoid.

Fastest way to determine if an integer's square root is an integer

If speed is a concern, why not partition off the most commonly used set of inputs and their values to a lookup table and then do whatever optimized magic algorithm you have come up with for the exceptional cases?

Can you call Directory.GetFiles() with multiple filters?

Make the extensions you want one string i.e ".mp3.jpg.wma.wmf" and then check if each file contains the extension you want. This works with .net 2.0 as it does not use LINQ.

string myExtensions=".jpg.mp3";

string[] files=System.IO.Directory.GetFiles("C:\myfolder");

foreach(string file in files)
{
   if(myExtensions.ToLower().contains(System.IO.Path.GetExtension(s).ToLower()))
   {
      //this file has passed, do something with this file

   }
}

The advantage with this approach is you can add or remove extensions without editing the code i.e to add png images, just write myExtensions=".jpg.mp3.png".

How to Truncate a string in PHP to the word closest to a certain number of characters?

The following solution was born when I've noticed a $break parameter of wordwrap function:

string wordwrap ( string $str [, int $width = 75 [, string $break = "\n" [, bool $cut = false ]]] )

Here is the solution:

/**
 * Truncates the given string at the specified length.
 *
 * @param string $str The input string.
 * @param int $width The number of chars at which the string will be truncated.
 * @return string
 */
function truncate($str, $width) {
    return strtok(wordwrap($str, $width, "...\n"), "\n");
}

Example #1.

print truncate("This is very long string with many chars.", 25);

The above example will output:

This is very long string...

Example #2.

print truncate("This is short string.", 25);

The above example will output:

This is short string.

Get last key-value pair in PHP array

try to use

end($array);

Return from lambda forEach() in java

I suggest you to first try to understand Java 8 in the whole picture, most importantly in your case it will be streams, lambdas and method references.

You should never convert existing code to Java 8 code on a line-by-line basis, you should extract features and convert those.

What I identified in your first case is the following:

  • You want to add elements of an input structure to an output list if they match some predicate.

Let's see how we do that, we can do it with the following:

List<Player> playersOfTeam = players.stream()
    .filter(player -> player.getTeam().equals(teamName))
    .collect(Collectors.toList());

What you do here is:

  1. Turn your input structure into a stream (I am assuming here that it is of type Collection<Player>, now you have a Stream<Player>.
  2. Filter out all unwanted elements with a Predicate<Player>, mapping every player to the boolean true if it is wished to be kept.
  3. Collect the resulting elements in a list, via a Collector, here we can use one of the standard library collectors, which is Collectors.toList().

This also incorporates two other points:

  1. Code against interfaces, so code against List<E> over ArrayList<E>.
  2. Use diamond inference for the type parameter in new ArrayList<>(), you are using Java 8 after all.

Now onto your second point:

You again want to convert something of legacy Java to Java 8 without looking at the bigger picture. This part has already been answered by @IanRoberts, though I think that you need to do players.stream().filter(...)... over what he suggested.

How do I get the YouTube video ID from a URL?

i wrote a function for that below:

function getYoutubeUrlId (url) {
    const urlObject = new URL(url);
    let urlOrigin = urlObject.origin;
    let urlPath = urlObject.pathname;

    if (urlOrigin.search('youtu.be') > -1) {
        return urlPath.substr(1);
    }

    if (urlPath.search('embed') > -1) {
        // Örnegin "/embed/wCCSEol8oSc" ise "wCCSEol8oSc" return eder.
        return urlPath.substr(7);
    }

   
    return urlObject.searchParams.get('v');
},

https://gist.github.com/semihkeskindev/8a4339c27203c5fabaf2824308c7868f

Making Maven run all tests, even when some fail

From the Maven Embedder documentation:

-fae,--fail-at-end Only fail the build afterwards; allow all non-impacted builds to continue

-fn,--fail-never NEVER fail the build, regardless of project result

So if you are testing one module than you are safe using -fae.

Otherwise, if you have multiple modules, and if you want all of them tested (even the ones that depend on the failing tests module), you should run mvn clean install -fn.
-fae will continue with the module that has a failing test (will run all other tests), but all modules that depend on it will be skipped.

Failed to execute 'postMessage' on 'DOMWindow': The target origin provided does not match the recipient window's origin ('null')

In My Case, Im trying to pass messages from Salesforce Marketing Cloud Custom Activity(Domain 1) to Heroku(Domain 2) on load.

The Error Appeared in console, when I loaded my original html page from where message is being passed.

Issue I noticed after reading many blogs is that, the receiver page is not loaded yet. i.e

I need to debug from my receiver page not from sender page.

Simple but glad if it helps anyone.

Python, add items from txt file into a list

The pythonic way to read a file and put every lines in a list:

from __future__ import with_statement #for python 2.5
Names = []
with open('C:/path/txtfile.txt', 'r') as f:
    lines = f.readlines()
    Names.append(lines.strip())

When do you use the "this" keyword?

I tend to underscore fields with _ so don't really ever need to use this. Also R# tends to refactor them away anyway...

Why does Git say my master branch is "already up to date" even though it is not?

Any changes you commit, like deleting all your project files, will still be in place after a pull. All a pull does is merge the latest changes from somewhere else into your own branch, and if your branch has deleted everything, then at best you'll get merge conflicts when upstream changes affect files you've deleted. So, in short, yes everything is up to date.

If you describe what outcome you'd like to have instead of "all files deleted", maybe someone can suggest an appropriate course of action.

Update:

GET THE MOST RECENT OF THE CODE ON MY SYSTEM

What you don't seem to understand is that you already have the most recent code, which is yours. If what you really want is to see the most recent of someone else's work that's on the master branch, just do:

git fetch upstream
git checkout upstream/master

Note that this won't leave you in a position to immediately (re)start your own work. If you need to know how to undo something you've done or otherwise revert changes you or someone else have made, then please provide details. Also, consider reading up on what version control is for, since you seem to misunderstand its basic purpose.

When is the finalize() method called in Java?

Try runiing this Program for better understanding

public class FinalizeTest 
{       
    static {
        System.out.println(Runtime.getRuntime().freeMemory());
    }

    public void run() {
        System.out.println("run");
        System.out.println(Runtime.getRuntime().freeMemory());
    }

     protected void finalize() throws Throwable { 
         System.out.println("finalize");
         while(true)
             break;          
     }

     public static void main(String[] args) {
            for (int i = 0 ; i < 500000 ; i++ ) {
                    new FinalizeTest().run();
            }
     }
}

Print all properties of a Python Class

In this simple case you can use vars():

an = Animal()
attrs = vars(an)
# {'kids': 0, 'name': 'Dog', 'color': 'Spotted', 'age': 10, 'legs': 2, 'smell': 'Alot'}
# now dump this in some way or another
print(', '.join("%s: %s" % item for item in attrs.items()))

If you want to store Python objects on the disk you should look at shelve — Python object persistence.

calling another method from the main method in java

If you want to use do() in your main method there are 2 choices because one is static but other (do()) not

  1. Create new instance and invoke do() like new Foo().do();
  2. make static do() method

Have a look at this sun tutorial

ng-if, not equal to?

There are pretty good solutions here but they don't help to understand why the problem actually happens.

But it's very simple, you just need to understand how logic OR || works. Whole expression will evaluate to true when either of its sides evaluates to true.

Now let's look at your case. Assume whole details.Payment[0].Status is Status and it's a number for brevity. Then we have Status != 0 || Status != 1 || ....

Imagine Status = 1:

( 1 != 0 || 1 != 1 || ... ) =
(  true  || false  || ... ) =
(       true       || ... ) = ... = true

Now imagine Status = 0:

( 0 != 0 || 0 != 1 || ... ) =
( false  ||  true  || ... ) =
(       true       || ... ) = ... = true

As you it doesn't even matter what you have as ... as logical OR of first two expressions gives you true which will be the result of the full expression.

What you actually need is logical AND && that will be true only if both its sides are true.

Is there any standard for JSON API response format?

Yes there are a couple of standards (albeit some liberties on the definition of standard) that have emerged:

  1. JSON API - JSON API covers creating and updating resources as well, not just responses.
  2. JSend - Simple and probably what you are already doing.
  3. OData JSON Protocol - Very complicated.
  4. HAL - Like OData but aiming to be HATEOAS like.

There are also JSON API description formats:

Moving items around in an ArrayList

Kotlin solution to move an Element from "fromPos" to "toPos" and shift all other items accordingly (useful for moving an item in a staggered layout recyclerView in an Android application)

            if(fromPos < toPos){                    
                val movingElement = myList[fromPos]
                //shifts all elements between fromPos and toPos 1 down
                for(i in fromPos+1..toPos){
                    myList[i-1] = myList[i]
                }
                //re-add element that was saved in the beginning
                myList[toPos] = movingElement
            }

            if(fromPos > toPos){
                val movingElement = myList[fromPos]
                //shifts elements between toPos and fromPos 1 up
                for(i in fromPos downTo toPos+1){
                    myList[i] = myList[i-1]
                }                    
                //re-add element that was saved in the beginning
                myList[toPos] = movingElement
            }

How do I block or restrict special characters from input fields with jquery?

Take a look at the jQuery alphanumeric plugin. https://github.com/KevinSheedy/jquery.alphanum

//All of these are from their demo page
//only numbers and alpha characters
$('.sample1').alphanumeric();
//only numeric
$('.sample4').numeric();
//only numeric and the .
$('.sample5').numeric({allow:"."});
//all alphanumeric except the . 1 and a
$('.sample6').alphanumeric({ichars:'.1a'});

How to call a JavaScript function, declared in <head>, in the body when I want to call it

Just drop

<script>
myfunction();
</script>

in the body where you want it to be called, understanding that when the page loads and the browser reaches that point, that's when the call will occur.

How do I get the MAX row with a GROUP BY in LINQ query?

In methods chain form:

db.Serials.GroupBy(i => i.Serial_Number).Select(g => new
    {
        Serial_Number = g.Key,
        uid = g.Max(row => row.uid)
    });

SQL, Postgres OIDs, What are they and why are they useful?

OIDs basically give you a built-in id for every row, contained in a system column (as opposed to a user-space column). That's handy for tables where you don't have a primary key, have duplicate rows, etc. For example, if you have a table with two identical rows, and you want to delete the oldest of the two, you could do that using the oid column.

OIDs are implemented using 4-byte unsigned integers. They are not unique–OID counter will wrap around at 2³²-1. OID are also used to identify data types (see /usr/include/postgresql/server/catalog/pg_type_d.h).

In my experience, the feature is generally unused in most postgres-backed applications (probably in part because they're non-standard), and their use is essentially deprecated:

In PostgreSQL 8.1 default_with_oids is off by default; in prior versions of PostgreSQL, it was on by default.

The use of OIDs in user tables is considered deprecated, so most installations should leave this variable disabled. Applications that require OIDs for a particular table should specify WITH OIDS when creating the table. This variable can be enabled for compatibility with old applications that do not follow this behavior.

Laravel update model with unique validation rule for attribute

public function rules()
{
    if ($this->method() == 'PUT') {
        $post_id = $this->segment(3);
        $rules = [
            'post_title' => 'required|unique:posts,post_title,' . $post_id
        ];
    } else {
        $rules = [
            'post_title' => 'required|unique:posts,post_title'
        ];
    }
    return $rules;
}

How to convert minutes to hours/minutes and add various time values together using jQuery?

The function below will take as input # of minutes and output time in the following format: Hours:minutes. I used Math.trunc(), which is a new method added in 2015. It returns the integral part of a number by removing any fractional digits.

function display(a){
  var hours = Math.trunc(a/60);
  var minutes = a % 60;
  console.log(hours +":"+ minutes);
}

display(120); //"2:0"
display(60); //"1:0:
display(100); //"1:40"
display(126); //"2:6"
display(45); //"0:45"

ImportError: No module named 'bottle' - PyCharm

in your PyCharm project:

  • press Ctrl+Alt+s to open the settings
  • on the left column, select Project Interpreter
  • on the top right there is a list of python binaries found on your system, pick the right one
  • eventually click the + button to install additional python modules
  • validate

enter image description here

socket.shutdown vs socket.close

Here's one explanation:

Once a socket is no longer required, the calling program can discard the socket by applying a close subroutine to the socket descriptor. If a reliable delivery socket has data associated with it when a close takes place, the system continues to attempt data transfer. However, if the data is still undelivered, the system discards the data. Should the application program have no use for any pending data, it can use the shutdown subroutine on the socket prior to closing it.

In Visual Studio Code How do I merge between two local branches?

You can do it without using plugins.

In the latest version of vscode that I'm using (1.17.0) you can simply open the branch that you want (from the bottom left menu) then press ctrl+shift+p and type Git: Merge branch and then choose the other branch that you want to merge from (to the current one)

How to set the margin or padding as percentage of height of parent container?

The fix is that yes, vertical padding and margin are relative to width, but top and bottom aren't.

So just place a div inside another, and in the inner div, use something like top:50% (remember position matters if it still doesn't work)

What is a NullPointerException, and how do I fix it?

A lot of explanations are already present to explain how it happens and how to fix it, but you should also follow best practices to avoid NullPointerExceptions at all.

See also: A good list of best practices

I would add, very important, make a good use of the final modifier. Using the "final" modifier whenever applicable in Java

Summary:

  1. Use the final modifier to enforce good initialization.
  2. Avoid returning null in methods, for example returning empty collections when applicable.
  3. Use annotations @NotNull and @Nullable
  4. Fail fast and use asserts to avoid propagation of null objects through the whole application when they shouldn't be null.
  5. Use equals with a known object first: if("knownObject".equals(unknownObject)
  6. Prefer valueOf() over toString().
  7. Use null safe StringUtils methods StringUtils.isEmpty(null).
  8. Use Java 8 Optional as return value in methods, Optional class provide a solution for representing optional values instead of null references.

How to load a UIView using a nib file created with Interface Builder

@AVeryDev

6) To attach the loaded view to your view controller's view:

[self.view addSubview:myViewFromNib];

Presumably, it is necessary to remove it from the view to avoid memory leaks.

To clarify: the view controller has several IBOutlets, some of which are connected to items in the original nib file (as usual), and some are connected to items in the loaded nib. Both nib's have the same owner class. The loaded view overlays the original one.

Hint: set the opacity of the main view in the loaded nib to zero, then it won't obscure the items from the original nib.

Maven home (M2_HOME) not being picked up by IntelliJ IDEA

Got to this answer ? probably the answers above are to long ...

just type in :

echo "setenv M2_HOME $M2_HOME" | sudo tee -a /etc/launchd.conf

and restart your mac (thats it!)

restarting is annoying ? just use the command :

grep -E "^setenv" /etc/launchd.conf | xargs -t -L 1 launchctl

and restart IntelliJ IDEA

Running MSBuild fails to read SDKToolsPath

ToolsVersion="4.0" does it for me in my MSBuild project:

<Project DefaultTargets="Do" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">

jQuery: count number of rows in a table

Here's my take on it:

//Helper function that gets a count of all the rows <TR> in a table body <TBODY>
$.fn.rowCount = function() {
    return $('tr', $(this).find('tbody')).length;
};

USAGE:

var rowCount = $('#productTypesTable').rowCount();

Select mySQL based only on month and year

SELECT * FROM projects WHERE YEAR(Date) = 2011 AND MONTH(Date) = 5

python pip: force install ignoring dependencies

pip has a --no-dependencies switch. You should use that.

For more information, run pip install -h, where you'll see this line:

--no-deps, --no-dependencies
                        Ignore package dependencies

How to remove unused imports in Intellij IDEA on commit?

You can check checkbox in the commit dialog.

enter image description here

You can use settings to automatically optimize imports since 11.1 and above.

enter image description here

How to use sessions in an ASP.NET MVC 4 application?

This is how session state works in ASP.NET and ASP.NET MVC:

ASP.NET Session State Overview

Basically, you do this to store a value in the Session object:

Session["FirstName"] = FirstNameTextBox.Text;

To retrieve the value:

var firstName = Session["FirstName"];

What are queues in jQuery?

To understand queue method, you have to understand how jQuery does animation. If you write multiple animate method calls one after the other, jQuery creates an 'internal' queue and adds these method calls to it. Then it runs those animate calls one by one.

Consider following code.

function nonStopAnimation()
{
    //These multiple animate calls are queued to run one after
    //the other by jQuery.
    //This is the reason that nonStopAnimation method will return immeidately
    //after queuing these calls. 
    $('#box').animate({ left: '+=500'}, 4000);
    $('#box').animate({ top: '+=500'}, 4000);
    $('#box').animate({ left: '-=500'}, 4000);

    //By calling the same function at the end of last animation, we can
    //create non stop animation. 
    $('#box').animate({ top: '-=500'}, 4000 , nonStopAnimation);
}

The 'queue'/'dequeue' method gives you control over this 'animation queue'.

By default the animation queue is named 'fx'. I have created a sample page here which has various examples which will illustrate how the queue method could be used.

http://jsbin.com/zoluge/1/edit?html,output

Code for above sample page:

$(document).ready(function() {
    $('#nonStopAnimation').click(nonStopAnimation);

    $('#stopAnimationQueue').click(function() {
        //By default all animation for particular 'selector'
        //are queued in queue named 'fx'.
        //By clearning that queue, you can stop the animation.
        $('#box').queue('fx', []);
    });

    $('#addAnimation').click(function() {
        $('#box').queue(function() {
            $(this).animate({ height : '-=25'}, 2000);
            //De-queue our newly queued function so that queues
            //can keep running.
            $(this).dequeue();
        });
    });

    $('#stopAnimation').click(function() {
        $('#box').stop();
    });

    setInterval(function() {
        $('#currentQueueLength').html(
         'Current Animation Queue Length for #box ' + 
          $('#box').queue('fx').length
        );
    }, 2000);
});

function nonStopAnimation()
{
    //These multiple animate calls are queued to run one after
    //the other by jQuery.
    $('#box').animate({ left: '+=500'}, 4000);
    $('#box').animate({ top: '+=500'}, 4000);
    $('#box').animate({ left: '-=500'}, 4000);
    $('#box').animate({ top: '-=500'}, 4000, nonStopAnimation);
}

Now you may ask, why should I bother with this queue? Normally, you wont. But if you have a complicated animation sequence which you want to control, then queue/dequeue methods are your friend.

Also see this interesting conversation on jQuery group about creating a complicated animation sequence.

http://groups.google.com/group/jquery-en/browse_thread/thread/b398ad505a9b0512/f4f3e841eab5f5a2?lnk=gst

Demo of the animation:

http://www.exfer.net/test/jquery/tabslide/

Let me know if you still have questions.

How do I jump to a closing bracket in Visual Studio Code?

Another Default Method:

Try pressing the ending bracket key ) again. It will move your cursor to the end of the brackets. I think it's a good practice to have the habit of typing both brackets.

T-SQL: Selecting rows to delete via joins

DELETE TableA
FROM   TableA a
       INNER JOIN TableB b
               ON b.Bid = a.Bid
                  AND [my filter condition] 

should work

How to add items to a spinner in Android?

Add a spinner to the XML layout, and then add this code to the Java file:

Spinner spinner;
spinner = (Spinner) findViewById(R.id.spinner1) ;
java.util.ArrayList<String> strings = new java.util.ArrayList<>();
strings.add("Mobile") ;
strings.add("Home");
strings.add("Work");
SpinnerAdapter spinnerAdapter = new SpinnerAdapter(AddMember.this, R.layout.support_simple_spinner_dropdown_item, strings);
spinner.setAdapter(spinnerAdapter);

Show tables, describe tables equivalent in redshift

I had to select from the information schema to get details of my tables and columns; in case it helps anyone:

SELECT * FROM information_schema.tables
WHERE table_schema = 'myschema'; 

SELECT * FROM information_schema.columns
WHERE table_schema = 'myschema' AND table_name = 'mytable'; 

Android: findviewbyid: finding view by id when view is not on the same layout invoked by setContentView

try:

Activity parentActivity = this.getParent();
if (parentActivity != null)
{
    View landmarkEditNameView = (EditText) parentActivity.findViewById(R.id. landmark_name_dialog_edit);
}

Detect if page has finished loading

var pageLoaded=0;

$(document).ready(function(){
   pageLoaded=1;
});

Using jquery: https://learn.jquery.com/using-jquery-core/document-ready/

Excel "External table is not in the expected format."

This can occur when the workbook is password-protected. There are some workarounds to remove this protection but most of the examples you'll find online are outdated. Either way, the simple solution is to unprotect the workbook manually, otherwise use something like OpenXML to remove the protection programmatically.

SELECT last id, without INSERT

I think to add timestamp to every record and get the latest. In this situation you can get any ids, pack rows and other ops.

Numpy: Divide each row by a vector element

JoshAdel's solution uses np.newaxis to add a dimension. An alternative is to use reshape() to align the dimensions in preparation for broadcasting.

data = np.array([[1,1,1],[2,2,2],[3,3,3]])
vector = np.array([1,2,3])

data
# array([[1, 1, 1],
#        [2, 2, 2],
#        [3, 3, 3]])
vector
# array([1, 2, 3])

data.shape
# (3, 3)
vector.shape
# (3,)

data / vector.reshape((3,1))
# array([[1, 1, 1],
#        [1, 1, 1],
#        [1, 1, 1]])

Performing the reshape() allows the dimensions to line up for broadcasting:

data:            3 x 3
vector:              3
vector reshaped: 3 x 1

Note that data/vector is ok, but it doesn't get you the answer that you want. It divides each column of array (instead of each row) by each corresponding element of vector. It's what you would get if you explicitly reshaped vector to be 1x3 instead of 3x1.

data / vector
# array([[1, 0, 0],
#        [2, 1, 0],
#        [3, 1, 1]])
data / vector.reshape((1,3))
# array([[1, 0, 0],
#        [2, 1, 0],
#        [3, 1, 1]])

What is the difference between a strongly typed language and a statically typed language?

This is often misunderstood so let me clear it up.

Static/Dynamic Typing

Static typing is where the type is bound to the variable. Types are checked at compile time.

Dynamic typing is where the type is bound to the value. Types are checked at run time.

So in Java for example:

String s = "abcd";

s will "forever" be a String. During its life it may point to different Strings (since s is a reference in Java). It may have a null value but it will never refer to an Integer or a List. That's static typing.

In PHP:

$s = "abcd";          // $s is a string
$s = 123;             // $s is now an integer
$s = array(1, 2, 3);  // $s is now an array
$s = new DOMDocument; // $s is an instance of the DOMDocument class

That's dynamic typing.

Strong/Weak Typing

(Edit alert!)

Strong typing is a phrase with no widely agreed upon meaning. Most programmers who use this term to mean something other than static typing use it to imply that there is a type discipline that is enforced by the compiler. For example, CLU has a strong type system that does not allow client code to create a value of abstract type except by using the constructors provided by the type. C has a somewhat strong type system, but it can be "subverted" to a degree because a program can always cast a value of one pointer type to a value of another pointer type. So for example, in C you can take a value returned by malloc() and cheerfully cast it to FILE*, and the compiler won't try to stop you—or even warn you that you are doing anything dodgy.

(The original answer said something about a value "not changing type at run time". I have known many language designers and compiler writers and have not known one that talked about values changing type at run time, except possibly some very advanced research in type systems, where this is known as the "strong update problem".)

Weak typing implies that the compiler does not enforce a typing discpline, or perhaps that enforcement can easily be subverted.

The original of this answer conflated weak typing with implicit conversion (sometimes also called "implicit promotion"). For example, in Java:

String s = "abc" + 123; // "abc123";

This is code is an example of implicit promotion: 123 is implicitly converted to a string before being concatenated with "abc". It can be argued the Java compiler rewrites that code as:

String s = "abc" + new Integer(123).toString();

Consider a classic PHP "starts with" problem:

if (strpos('abcdef', 'abc') == false) {
  // not found
}

The error here is that strpos() returns the index of the match, being 0. 0 is coerced into boolean false and thus the condition is actually true. The solution is to use === instead of == to avoid implicit conversion.

This example illustrates how a combination of implicit conversion and dynamic typing can lead programmers astray.

Compare that to Ruby:

val = "abc" + 123

which is a runtime error because in Ruby the object 123 is not implicitly converted just because it happens to be passed to a + method. In Ruby the programmer must make the conversion explicit:

val = "abc" + 123.to_s

Comparing PHP and Ruby is a good illustration here. Both are dynamically typed languages but PHP has lots of implicit conversions and Ruby (perhaps surprisingly if you're unfamiliar with it) doesn't.

Static/Dynamic vs Strong/Weak

The point here is that the static/dynamic axis is independent of the strong/weak axis. People confuse them probably in part because strong vs weak typing is not only less clearly defined, there is no real consensus on exactly what is meant by strong and weak. For this reason strong/weak typing is far more of a shade of grey rather than black or white.

So to answer your question: another way to look at this that's mostly correct is to say that static typing is compile-time type safety and strong typing is runtime type safety.

The reason for this is that variables in a statically typed language have a type that must be declared and can be checked at compile time. A strongly-typed language has values that have a type at run time, and it's difficult for the programmer to subvert the type system without a dynamic check.

But it's important to understand that a language can be Static/Strong, Static/Weak, Dynamic/Strong or Dynamic/Weak.

Cluster analysis in R: determine the optimal number of clusters

A simple solution is the library factoextra. You can change the clustering method and the method for calculate the best number of groups. For example if you want to know the best number of clusters for a k- means:

Data: mtcars

library(factoextra)   
fviz_nbclust(mtcars, kmeans, method = "wss") +
      geom_vline(xintercept = 3, linetype = 2)+
      labs(subtitle = "Elbow method")

Finally, we get a graph like:

enter image description here

JavaScript: changing the value of onclick with or without jQuery

Came up with a quick and dirty fix to this. Just used <select onchange='this.options[this.selectedIndex].onclick();> <option onclick='alert("hello world")' ></option> </select>

Hope this helps

How to iterate std::set?

Another example for the C++11 standard:

set<int> data;
data.insert(4);
data.insert(5);

for (const int &number : data)
  cout << number;

How to check if any fields in a form are empty in php

your form is missing the method...

<form name="registrationform" action="register.php" method="post"> //here

anywyas to check the posted data u can use isset()..

Determine if a variable is set and is not NULL

if(!isset($firstname) || trim($firstname) == '')
{
   echo "You did not fill out the required fields.";
}

Add element to a JSON file?

You can do this.

data[0]['f'] = var

UIImage resize (Scale proportion)

That's ok not a big problem . thing is u got to find the proportional width and height

like if size is 2048.0 x 1360.0 which has to be resized to 320 x 480 resolution then the resulting image size should be 722.0 x 480.0

here is the formulae to do that . if w,h is original and x,y are resulting image.
w/h=x/y 
=> 
x=(w/h)*y;  

submitting w=2048,h=1360,y=480 => x=722.0 ( here width>height. if height>width then consider x to be 320 and calculate y)

U can submit in this web page . ARC

Confused ? alright , here is category for UIImage which will do the thing for you.

@interface UIImage (UIImageFunctions)
    - (UIImage *) scaleToSize: (CGSize)size;
    - (UIImage *) scaleProportionalToSize: (CGSize)size;
@end
@implementation UIImage (UIImageFunctions)

- (UIImage *) scaleToSize: (CGSize)size
{
    // Scalling selected image to targeted size
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
    CGContextRef context = CGBitmapContextCreate(NULL, size.width, size.height, 8, 0, colorSpace, kCGImageAlphaPremultipliedLast);
    CGContextClearRect(context, CGRectMake(0, 0, size.width, size.height));

    if(self.imageOrientation == UIImageOrientationRight)
    {
        CGContextRotateCTM(context, -M_PI_2);
        CGContextTranslateCTM(context, -size.height, 0.0f);
        CGContextDrawImage(context, CGRectMake(0, 0, size.height, size.width), self.CGImage);
    }
    else
        CGContextDrawImage(context, CGRectMake(0, 0, size.width, size.height), self.CGImage);

    CGImageRef scaledImage=CGBitmapContextCreateImage(context);

    CGColorSpaceRelease(colorSpace);
    CGContextRelease(context);

    UIImage *image = [UIImage imageWithCGImage: scaledImage];

    CGImageRelease(scaledImage);

    return image;
}

- (UIImage *) scaleProportionalToSize: (CGSize)size1
{
    if(self.size.width>self.size.height)
    {
        NSLog(@"LandScape");
        size1=CGSizeMake((self.size.width/self.size.height)*size1.height,size1.height);
    }
    else
    {
        NSLog(@"Potrait");
        size1=CGSizeMake(size1.width,(self.size.height/self.size.width)*size1.width);
    }

    return [self scaleToSize:size1];
}

@end

-- the following is appropriate call to do this if img is the UIImage instance.

img=[img scaleProportionalToSize:CGSizeMake(320, 480)];

How to Debug Variables in Smarty like in PHP var_dump()

If you want something prettier I would advise

{"<?php\n\$data =\n"|@cat:{$yourvariable|@var_export:true|@cat:";\n?>"}|@highlight_string:true}

just replace yourvariable by your variable

Mongoose limit/offset and count query

There is a library that will do all of this for you, check out mongoose-paginate-v2

How to create a stacked bar chart for my DataFrame using seaborn?

You could use pandas plot as @Bharath suggest:

import seaborn as sns
sns.set()
df.set_index('App').T.plot(kind='bar', stacked=True)

Output:

enter image description here

Updated:

from matplotlib.colors import ListedColormap df.set_index('App')\ .reindex_axis(df.set_index('App').sum().sort_values().index, axis=1)\ .T.plot(kind='bar', stacked=True, colormap=ListedColormap(sns.color_palette("GnBu", 10)), figsize=(12,6))

Updated Pandas 0.21.0+ reindex_axis is deprecated, use reindex

from matplotlib.colors import ListedColormap

df.set_index('App')\
  .reindex(df.set_index('App').sum().sort_values().index, axis=1)\
  .T.plot(kind='bar', stacked=True,
          colormap=ListedColormap(sns.color_palette("GnBu", 10)), 
          figsize=(12,6))

Output:

enter image description here

Printing Exception Message in java

try {
} catch (javax.script.ScriptException ex) {
// System.out.println(ex.getMessage());
}

How do I show a running clock in Excel?

See the below code (taken from this post)

Put this code in a Module in VBA (Developer Tab -> Visual Basic)

Dim TimerActive As Boolean
Sub StartTimer()
    Start_Timer
End Sub
Private Sub Start_Timer()
    TimerActive = True
    Application.OnTime Now() + TimeValue("00:01:00"), "Timer"
End Sub
Private Sub Stop_Timer()
    TimerActive = False
End Sub
Private Sub Timer()
    If TimerActive Then
        ActiveSheet.Cells(1, 1).Value = Time
        Application.OnTime Now() + TimeValue("00:01:00"), "Timer"
    End If
End Sub

You can invoke the "StartTimer" function when the workbook opens and have it repeat every minute by adding the below code to your workbooks Visual Basic "This.Workbook" class in the Visual Basic editor.

Private Sub Workbook_Open()
    Module1.StartTimer
End Sub

Now, every time 1 minute passes the Timer procedure will be invoked, and set cell A1 equal to the current time.

Python: import module from another directory at the same level in project hierarchy

In the "root" __init__.py you can also do a

import sys
sys.path.insert(1, '.')

which should make both modules importable.

User Get-ADUser to list all properties and export to .csv

This can be simplified by completely skipping the where object and the $users declaration. All you need is:

Code

get-content c:\scripts\users.txt | get-aduser -properties * | select displayname, office | export-csv c:\path\to\your.csv

filemtime "warning stat failed for"

Shorter version for those who like short code:

// usage: deleteOldFiles("./xml", "xml,xsl", 24 * 3600)


function deleteOldFiles($dir, $patterns = "*", int $timeout = 3600) {

    // $dir is directory, $patterns is file types e.g. "txt,xls", $timeout is max age

    foreach (glob($dir."/*"."{{$patterns}}",GLOB_BRACE) as $f) { 

        if (is_writable($f) && filemtime($f) < (time() - $timeout))
            unlink($f);

    }

}

/usr/bin/codesign failed with exit code 1

I had the same problem but also listed in the error log was this: CSSMERR_TP_CERT_NOT_VALID_YET

Looking at the certificate in KeyChain showed a similar message. The problem was due to my Mac's system clock being set incorrectly. As soon as I set the correct region/time, the certificate was marked as valid and I could build and run my app on the iPhone

How can I display my windows user name in excel spread sheet using macros?

Range("A1").value = Environ("Username")

This is better than Application.Username, which doesn't always supply the Windows username. Thanks to Kyle for pointing this out.

  • Application Username is the name of the User set in Excel > Tools > Options
  • Environ("Username") is the name you registered for Windows; see Control Panel >System

bootstrap 3 - how do I place the brand in the center of the navbar?

Another option is to use nav-justified..

<nav class="navbar navbar-default" role="navigation">
  <div class="navbar-header">
    <button type="button" class="navbar-toggle" data-toggle="collapse" data-target=".navbar-collapse">
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
      <span class="icon-bar"></span>
    </button>    
  </div>
  <div class="navbar-collapse collapse">
    <ul class="nav nav-justified">
      <li><a href="#" class="navbar-brand">Brand</a></li>
    </ul>
  </div>
</nav>

CSS

.navbar-brand {
    float:none;
}

Bootply

Alternate example

Integrate ZXing in Android Studio

Anybody facing the same issues, follow the simple steps:

Import the project android from downloaded zxing-master zip file using option Import project (Eclipse ADT, Gradle, etc.) and add the dollowing 2 lines of codes in your app level build.gradle file and and you are ready to run.

So simple, yahh...

dependencies {
        // https://mvnrepository.com/artifact/com.google.zxing/core
        compile group: 'com.google.zxing', name: 'core', version: '3.2.1'
        // https://mvnrepository.com/artifact/com.google.zxing/android-core
        compile group: 'com.google.zxing', name: 'android-core', version: '3.2.0'

    }

You can always find latest version core and android core from below links:

https://mvnrepository.com/artifact/com.google.zxing/core/3.2.1 https://mvnrepository.com/artifact/com.google.zxing/android-core/3.2.0

UPDATE (29.05.2019)

Add these dependencies instead:

dependencies {
    implementation 'com.google.zxing:core:3.4.0'
    implementation 'com.google.zxing:android-core:3.3.0'
}

Android dependency has different version for the compile and runtime

You should be able to see exactly which dependency is pulling in the odd version as a transitive dependency by running the correct gradle -q dependencies command for your project as described here:

https://docs.gradle.org/current/userguide/userguide_single.html#sec:listing_dependencies

Once you track down what's pulling it in, you can add an exclude to that specific dependency in your gradle file with something like:

implementation("XXXXX") {
    exclude group: 'com.android.support', module: 'support-compat'
}

How can I capitalize the first letter of each word in a string?

In case you want to downsize

# Assuming you are opening a new file
with open(input_file) as file:
    lines = [x for x in reader(file) if x]

# for loop to parse the file by line
for line in lines:
    name = [x.strip().lower() for x in line if x]
    print(name) # Check the result

how to get docker-compose to use the latest image from repository

Option down resolve this problem

I run my compose file:

docker-compose -f docker/docker-compose.yml up -d

then I delete all with down --rmi all

docker-compose -f docker/docker-compose.yml down --rmi all

Stops containers and removes containers, networks, volumes, and images
created by `up`.

By default, the only things removed are:

- Containers for services defined in the Compose file
- Networks defined in the `networks` section of the Compose file
- The default network, if one is used

Networks and volumes defined as `external` are never removed.

Usage: down [options]

Options:
    --rmi type          Remove images. Type must be one of:
                        'all': Remove all images used by any service.
                        'local': Remove only images that don't have a custom tag
                        set by the `image` field.
    -v, --volumes       Remove named volumes declared in the `volumes` section
                        of the Compose file and anonymous volumes
                        attached to containers.
    --remove-orphans    Remove containers for services not defined in the
                        Compose file

Git for beginners: The definitive practical guide

How do you create a new project/repository?

A git repository is simply a directory containing a special .git directory.

This is different from "centralised" version-control systems (like subversion), where a "repository" is hosted on a remote server, which you checkout into a "working copy" directory. With git, your working copy is the repository.

Simply run git init in the directory which contains the files you wish to track.

For example,

cd ~/code/project001/
git init

This creates a .git (hidden) folder in the current directory.

To make a new project, run git init with an additional argument (the name of the directory to be created):

git init project002

(This is equivalent to: mkdir project002 && cd project002 && git init)

To check if the current current path is within a git repository, simply run git status - if it's not a repository, it will report "fatal: Not a git repository"

You could also list the .git directory, and check it contains files/directories similar to the following:

$ ls .git
HEAD         config       hooks/       objects/
branches/    description  info/        refs/

If for whatever reason you wish to "de-git" a repository (you wish to stop using git to track that project). Simply remove the .git directory at the base level of the repository.

cd ~/code/project001/
rm -rf .git/

Caution: This will destroy all revision history, all your tags, everything git has done. It will not touch the "current" files (the files you can currently see), but previous changes, deleted files and so on will be unrecoverable!

Creating a new database and new connection in Oracle SQL Developer

This tutorial should help you:

Getting Started with Oracle SQL Developer

See the prerequisites:

  1. Install Oracle SQL Developer. You already have it.
  2. Install the Oracle Database. Download available here.
  3. Unlock the HR user. Login to SQL*Plus as the SYS user and execute the following command:

    alter user hr identified by hr account unlock;

  4. Download and unzip the sqldev_mngdb.zip file that contains all the files you need to perform this tutorial.


Another version from May 2011: Getting Started with Oracle SQL Developer


For more info check this related question:

How to create a new database after initally installing oracle database 11g Express Edition?

How can I add a volume to an existing Docker container?

A note for using Docker Windows containers after I had to look for this problem for a long time!

Condiditions:

  • Windows 10
  • Docker Desktop (latest version)
  • using Docker Windows Container for image microsoft/mssql-server-windows-developer

Problem:

  • I wanted to mount a host dictionary into my windows container.

Solution as partially discripted here:

  • create docker container

docker run -d -p 1433:1433 -e sa_password=<STRONG_PASSWORD> -e ACCEPT_EULA=Y microsoft/mssql-server-windows-developer

  • go to command shell in container

docker exec -it <CONTAINERID> cmd.exe

  • create DIR

mkdir DirForMount

  • stop container

docker container stop <CONTAINERID>

  • commit container

docker commit <CONTAINERID> <NEWIMAGENAME>

  • delete old container

docker container rm <CONTAINERID>

  • create new container with new image and volume mounting

docker run -d -p 1433:1433 -e sa_password=<STRONG_PASSWORD> -e ACCEPT_EULA=Y -v C:\DirToMount:C:\DirForMount <NEWIMAGENAME>

After this i solved this problem on docker windows containers.

How to send a simple email from a Windows batch file?

It works for me, by using double quotes around variables.

I am using batch script to call powershell Send-MailMessage

Batch Script:send_email.bat

C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe  -command 'E:\path\send_email.ps1

Pwershell Script send_email.ps1

Send-MailMessage -From "noreply@$env:computername" -To '<[email protected]>' -Subject 'Blah Blah' -SmtpServer  'smtp.domain.com'  -Attachments 'E:\path\file.log' -BODY "Blah Blah on Host: $env:computername "

Laravel 5 How to switch from Production mode

In Laravel the default environment is always production.

What you need to do is to specify correct hostname in bootstrap/start.php for your enviroments eg.:

/*
|--------------------------------------------------------------------------
| Detect The Application Environment
|--------------------------------------------------------------------------
|
| Laravel takes a dead simple approach to your application environments
| so you can just specify a machine name for the host that matches a
| given environment, then we will automatically detect it for you.
|
*/

$env = $app->detectEnvironment(array(
    'local' => array('homestead'),
    'profile_1' => array('hostname_for_profile_1')
));

How to remove all of the data in a table using Django

Django 1.11 delete all objects from a database table -

Entry.objects.all().delete()  ## Entry being Model Name. 

Refer the Official Django documentation here as quoted below - https://docs.djangoproject.com/en/1.11/topics/db/queries/#deleting-objects

Note that delete() is the only QuerySet method that is not exposed on a Manager itself. This is a safety mechanism to prevent you from accidentally requesting Entry.objects.delete(), and deleting all the entries. If you do want to delete all the objects, then you have to explicitly request a complete query set:

I myself tried the code snippet seen below within my somefilename.py

    # for deleting model objects
    from django.db import connection
    def del_model_4(self):
        with connection.schema_editor() as schema_editor:
            schema_editor.delete_model(model_4)

and within my views.py i have a view that simply renders a html page ...

  def data_del_4(request):
      obj = calc_2() ## 
      obj.del_model_4()
      return render(request, 'dc_dash/data_del_4.html') ## 

it ended deleting all entries from - model == model_4 , but now i get to see a Error screen within Admin console when i try to asceratin that all objects of model_4 have been deleted ...

ProgrammingError at /admin/dc_dash/model_4/
relation "dc_dash_model_4" does not exist
LINE 1: SELECT COUNT(*) AS "__count" FROM "dc_dash_model_4" 

Do consider that - if we do not go to the ADMIN Console and try and see objects of the model - which have been already deleted - the Django app works just as intended.

django admin screencapture

How do I create an .exe for a Java program?

I used exe4j to package all java jars into one final .exe file, which user can use it as normal windows application.

How do I make a Windows batch script completely silent?

You can redirect stdout to nul to hide it.

COPY %scriptDirectory%test.bat %scriptDirectory%test2.bat >nul

Just add >nul to the commands you want to hide the output from.

Here you can see all the different ways of redirecting the std streams.

How do I build JSON dynamically in javascript?

First, I think you're calling it the wrong thing. "JSON" stands for "JavaScript Object Notation" - it's just a specification for representing some data in a string that explicitly mimics JavaScript object (and array, string, number and boolean) literals. You're trying to build up a JavaScript object dynamically - so the word you're looking for is "object".

With that pedantry out of the way, I think that you're asking how to set object and array properties.

// make an empty object
var myObject = {};

// set the "list1" property to an array of strings
myObject.list1 = ['1', '2'];

// you can also access properties by string
myObject['list2'] = [];
// accessing arrays is the same, but the keys are numbers
myObject.list2[0] = 'a';
myObject['list2'][1] = 'b';

myObject.list3 = [];
// instead of placing properties at specific indices, you
// can push them on to the end
myObject.list3.push({});
// or unshift them on to the beginning
myObject.list3.unshift({});
myObject.list3[0]['key1'] = 'value1';
myObject.list3[1]['key2'] = 'value2';

myObject.not_a_list = '11';

That code will build up the object that you specified in your question (except that I call it myObject instead of myJSON). For more information on accessing properties, I recommend the Mozilla JavaScript Guide and the book JavaScript: The Good Parts.

What is the best way to call a script from another script?

This process is somewhat un-orthodox, but would work across all python versions,

Suppose you want to execute a script named 'recommend.py' inside an 'if' condition, then use,

if condition:
       import recommend

The technique is different, but works!

Remove new lines from string and replace with one empty space

You have to be cautious of double line breaks, which would cause double spaces. Use this really efficient regular expression:

$string = trim(preg_replace('/\s\s+/', ' ', $string));

Multiple spaces and newlines are replaced with a single space.

Edit: As others have pointed out, this solution has issues matching single newlines in between words. This is not present in the example, but one can easily see how that situation could occur. An alternative is to do the following:

$string = trim(preg_replace('/\s+/', ' ', $string));

Checking during array iteration, if the current element is the last element

$arr = array(1, 'a', 3, 4 => 1, 'b' => 1);
foreach ($arr as $key => $val) {
    echo "{$key} = {$val}" . (end(array_keys($arr))===$key ? '' : ', ');
}
// output: 0 = 1, 1 = a, 2 = 3, 4 = 1, b = 1

How to get user's high resolution profile picture on Twitter?

use this URL : "https://twitter.com/(userName)/profile_image?size=original"

If you are using TWitter SDK you can get the user name when logged in, with TWTRAPIClient, using TWTRAuthSession.

This is the code snipe for iOS:

if let twitterId = session.userID{
   let twitterClient = TWTRAPIClient(userID: twitterId)
   twitterClient.loadUser(withID: twitterId) {(user, error) in
       if let userName = user?.screenName{
          let url = "https://twitter.com/\(userName)/profile_image?size=original")
       }
   }
}

Rounding numbers to 2 digits after comma

I use this:

_x000D_
_x000D_
function round(value, precision) {_x000D_
_x000D_
 if(precision == 0)_x000D_
  return Math.round(value);   _x000D_
_x000D_
 exp = 1;_x000D_
 for(i=0;i<precision;i++)_x000D_
  exp *= 10;_x000D_
_x000D_
 return Math.round(value*exp)/exp;_x000D_
}
_x000D_
_x000D_
_x000D_

Why is using the JavaScript eval function a bad idea?

Besides the possible security issues if you are executing user-submitted code, most of the time there's a better way that doesn't involve re-parsing the code every time it's executed. Anonymous functions or object properties can replace most uses of eval and are much safer and faster.

How to position the form in the center screen?

Simply set location relative to null after calling pack on the JFrame, that's it.

e.g.,

  JFrame frame = new JFrame("FooRendererTest");
  frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  frame.getContentPane().add(mainPanel); // or whatever...
  frame.pack();
  frame.setLocationRelativeTo(null);  // *** this will center your app ***
  frame.setVisible(true);

How to show and update echo on same line

This is vary useful please try it and change as required.

#!/bin/bash
for load in $(seq 1 100); do
    echo -ne "$load % downloded ...\r"
    sleep 1
done
echo "100"
echo "Loaded ..."

Column order manipulation using col-lg-push and col-lg-pull in Twitter Bootstrap 3

Misconception Common misconception with column ordering is that, I should (or could) do the pushing and pulling on mobile devices, and that the desktop views should render in the natural order of the markup. This is wrong.

Reality Bootstrap is a mobile first framework. This means that the order of the columns in your HTML markup should represent the order in which you want them displayed on mobile devices. This mean that the pushing and pulling is done on the larger desktop views. not on mobile devices view..

Brandon Schmalz - Full Stack Web Developer Have a look at full description here

Corrupted Access .accdb file: "Unrecognized Database Format"

After much struggle with this same issue I was able to solve the problem by installing the 32 bit version of the 2010 Access Database Engine. For some reason the 64bit version generates this error...

DB query builder toArray() laravel 4

Easiest way is using laravel toArray function itself:

    $result = array_map(function ($value) {
        return $value instanceof Arrayable ? $value->toArray() : $value;
    }, $result);

How to set the min and max height or width of a Frame?

A workaround - at least for the minimum size: You can use grid to manage the frames contained in root and make them follow the grid size by setting sticky='nsew'. Then you can use root.grid_rowconfigure and root.grid_columnconfigure to set values for minsize like so:

from tkinter import Frame, Tk

class MyApp():
    def __init__(self):
        self.root = Tk()

        self.my_frame_red = Frame(self.root, bg='red')
        self.my_frame_red.grid(row=0, column=0, sticky='nsew')

        self.my_frame_blue = Frame(self.root, bg='blue')
        self.my_frame_blue.grid(row=0, column=1, sticky='nsew')

        self.root.grid_rowconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(1, weight=1)

        self.root.mainloop()

if __name__ == '__main__':
    app = MyApp()

But as Brian wrote (in 2010 :D) you can still resize the window to be smaller than the frame if you don't limit its minsize.

Styling HTML email for Gmail

I agree with everyone who supports classes AND inline styles. You might have learned this by now, but if there is a single mistake in your style sheet, Gmail will disregard it.

You might think that your CSS is perfect, because you've done it so often, why would I have mistakes in my CSS? Run it through the CSS Validator (for example http://www.css-validator.org/) and see what happens. I did that after encountering some Gmail display issues, and to my surprise, several Microsoft Outlook specific style declarations showed up as mistakes.

Which made sense to me, so I removed them from the style sheet and put them into a only for Microsoft code block, like so:

<!--[if mso]>
<style type="text/css">
body, table, td, .mobile-text {
font-family: Arial, sans-serif !important;
}
</style>
<xml>
  <o:OfficeDocumentSettings>
    <o:AllowPNG/>
    <o:PixelsPerInch>96</o:PixelsPerInch>
  </o:OfficeDocumentSettings>
</xml>
<![endif]-->

This is just a simple example, but, who know, it might come in handy some time.

How to switch Python versions in Terminal?

Here is a nice and simple way to do it (but on CENTOS), without braking the operating system.

yum install scl-utils

next

yum install centos-release-scl-rh

And lastly you install the version that you want, lets say python3.5

yum install rh-python35

And lastly:

scl enable rh-python35 bash

Since MAC-OS is a unix operating system, the way to do it it should be quite similar.

Encrypt and Decrypt text with RSA in PHP

I have difficulty in decrypting a long string that is encrypted in python. Here is the python encryption function:

def RSA_encrypt(public_key, msg, chunk_size=214):
    """
    Encrypt the message by the provided RSA public key.

    :param public_key: RSA public key in PEM format.
    :type public_key: binary
    :param msg: message that to be encrypted
    :type msg: string
    :param chunk_size: the chunk size used for PKCS1_OAEP decryption, it is determined by \
    the private key length used in bytes - 42 bytes.
    :type chunk_size: int
    :return: Base 64 encryption of the encrypted message
    :rtype: binray
    """
    rsa_key = RSA.importKey(public_key)
    rsa_key = PKCS1_OAEP.new(rsa_key)

    encrypted = b''
    offset = 0
    end_loop = False

    while not end_loop:
        chunk = msg[offset:offset + chunk_size]

        if len(chunk) % chunk_size != 0:
            chunk += " " * (chunk_size - len(chunk))
            end_loop = True

        encrypted += rsa_key.encrypt(chunk.encode())
        offset += chunk_size

    return base64.b64encode(encrypted)

The decryption in PHP:

/**
 * @param  base64_encoded string holds the encrypted message.
 * @param  Resource your private key loaded using openssl_pkey_get_private
 * @param  integer Chunking by bytes to feed to the decryptor algorithm.
 * @return String decrypted message.
 */
public function RSADecyrpt($encrypted_msg, $ppk, $chunk_size=256){
    if(is_null($ppk))
        throw new Exception("Returned message is encrypted while you did not provide private key!");
    $encrypted_msg = base64_decode($encrypted_msg);

    $offset = 0;
    $chunk_size = 256;

    $decrypted = "";
    while($offset < strlen($encrypted_msg)){
        $decrypted_chunk = "";
        $chunk = substr($encrypted_msg, $offset, $chunk_size);

        if(openssl_private_decrypt($chunk, $decrypted_chunk, $ppk, OPENSSL_PKCS1_OAEP_PADDING))
            $decrypted .= $decrypted_chunk;
        else 
            throw new exception("Problem decrypting the message");
        $offset += $chunk_size;
    }
    return $decrypted;
}

Convert string to buffer Node

You can do:

var buf = Buffer.from(bufStr, 'utf8');

But this is a bit silly, so another suggestion would be to copy the minimal amount of code out of the called function to allow yourself access to the original buffer. This might be quite easy or fairly difficult depending on the details of that library.

Android basics: running code in the UI thread

I like the one from HPP comment, it can be used anywhere without any parameter:

new Handler(Looper.getMainLooper()).post(new Runnable() {
    @Override
    public void run() {
        Log.d("UI thread", "I am the UI thread");
    }
});

.NET Format a string with fixed spaces

Thanks for the discussion, this method also works (VB):

Public Function StringCentering(ByVal s As String, ByVal desiredLength As Integer) As String
    If s.Length >= desiredLength Then Return s
    Dim firstpad As Integer = (s.Length + desiredLength) / 2
    Return s.PadLeft(firstpad).PadRight(desiredLength)
End Function
  1. StringCentering() takes two input values and it returns a formatted string.
  2. When length of s is greater than or equal to deisredLength, the function returns the original string.
  3. When length of s is smaller than desiredLength, it will be padded both ends.
  4. Due to character spacing is integer and there is no half-space, we can have an uneven split of space. In this implementation, the greater split goes to the leading end.
  5. The function requires .NET Framework due to PadLeft() and PadRight().
  6. In the last line of the function, binding is from left to right, so firstpad is applied followed by the desiredLength pad.

Here is the C# version:

public string StringCentering(string s, int desiredLength)
{
    if (s.Length >= desiredLength) return s;
    int firstpad = (s.Length + desiredLength) / 2;
    return s.PadLeft(firstpad).PadRight(desiredLength);
}

To aid understanding, integer variable firstpad is used. s.PadLeft(firstpad) applies the (correct number of) leading white spaces. The right-most PadRight(desiredLength) has a lower binding finishes off by applying trailing white spaces.

Windows service start failure: Cannot start service from the command line or debugger

Your code has nothing to do with the service installation, it is not the problem.

In order to test the service, you must install it as indicated.

For more information about installing your service : Installing and Uninstalling Services

How do you force a CIFS connection to unmount

A lazy unmount will do the job for you.

umount -l <mount path>

jQuery onclick event for <li> tags

Typing in $(this) will return the jQuery element instead of the HTML Element. Then it just depends on what you want to do in the click event.

alert($(this));

Resize command prompt through commands

Although the answers given here can be used to temporarily change window size, they don't seem to affect font size (at least not on my PC). I have an alternative way. I don't know if this what you're looking for but if you want to make changes automatically/permanently to Console font/window size, you can always do a script that edits the registry:

HKEY_CURRENT_USER\Console
HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe
HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe

Those keys deal with the consoles that come up when your run a script or press shift and select "open command prompt here". The Command Prompt entry in your start menu does not use the registry to store it's preferences but stores the prefs in the shortcut itself.

I have a monitor that I can run in 720p native or 1440p supersampling. I needed a quick way to change my console's font/window size, so I made these scripts. These scripts do two things: (1) change the font/window sizes in the registry and (2) swap out the shortcuts in the Start menu with ones that have a different window and font size. I basically made two sets of copies of the Command Prompt and Power Shell shortcuts and stored them in Documents. One set of shortcuts was configured with Consolas font size at 16 for my monitor is in 720p (called it "Command Prompt.720pRes.lnk") and another version of the same shortcut was configure with font size at 36 (called it "Command Prompt.HighRes.lnk"). The script will copy from the set I want to use to overwrite the Start menu one.

console-1440p.cmd:

::Assign New Window and Font Size for Windows Command Prompt
set CMDpNewFont=00240000
set CMDpNewWindowSize=000f0078
set commandPromptLinkFlag=highRes



 ::Make temporary .reg file to resize command console

>%temp%\consoleSIZEchanger.reg ECHO Windows Registry Editor Version 5.00
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%


::Merge and delete consoleSIZEchanger.reg
REGEDIT /S %temp%\consoleSIZEchanger.reg 
del %temp%\consoleSIZEchanger.reg 

::Copy Preconfigured Command Prompt/PowerShell shortcuts to Pinned Start Menu, Accessories and any other Custom Location you would define
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Accessories\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell.lnk"                 
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell (x86).lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell (x86).lnk"

console-720p.cmd:

::Assign New Window and Font Size for Windows Command Prompt
set CMDpNewFont=00100000
set CMDpNewWindowSize=0014007d
set commandPromptLinkFlag=720Res



 ::Make temporary .reg file to resize command console
>%temp%\consoleSIZEchanger.reg ECHO Windows Registry Editor Version 5.00
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_cmd.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%
>>%temp%\consoleSIZEchanger.reg ECHO.
>>%temp%\consoleSIZEchanger.reg ECHO [HKEY_CURRENT_USER\Console\%%SystemRoot%%_system32_WindowsPowerShell_v1.0_powershell.exe]
>>%temp%\consoleSIZEchanger.reg ECHO "WindowSize"=dword:%CMDpNewWindowSize%
>>%temp%\consoleSIZEchanger.reg ECHO "FontSize"=dword:%CMDpNewFont%


::Merge and delete consoleSIZEchanger.reg
REGEDIT /S %temp%\consoleSIZEchanger.reg 
del %temp%\consoleSIZEchanger.reg 

::Copy Preconfigured Command Prompt/PowerShell shortcuts to Pinned Start Menu, Accessories and any other Custom Location you would define
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Command Prompt.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Accessories\Command Prompt.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell.lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell.%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell.lnk"                 
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%\ProgramData\Microsoft\Windows\Start Menu\Programs\Accessories\Windows PowerShell\Windows PowerShell (x86).lnk"
copy "%homedrive%%homepath%\Documents\Windows PowerShell (x86).%commandPromptLinkFlag%.lnk" "%homedrive%%homepath%\AppData\Roaming\Microsoft\Internet Explorer\Quick Launch\User Pinned\StartMenu\Windows PowerShell (x86).lnk"

What is the difference between HAVING and WHERE in SQL?

When GROUP BY is not used, the WHERE and HAVING clauses are essentially equivalent.

However, when GROUP BY is used:

  • The WHERE clause is used to filter records from a result. The filtering occurs before any groupings are made.
  • The HAVING clause is used to filter values from a group (i.e., to check conditions after aggregation into groups has been performed).

Resource from Here

Skip over a value in the range function in python

for i in range(0, 101):
if i != 50:
    do sth
else:
    pass

Split array into two parts without for loop in java

copyOfRange

This does what you want without you having to create a new array as it returns a new array.

int[] original = new int[300000];
int[] firstHalf = Arrays.copyOfRange(original, 0, original.length/2);

Insert variable values in the middle of a string

I would use a StringBuilder class for doing string manipulation as it will more efficient (being mutable)

string flights = "Flight A, B,C,D";
StringBuilder message = new StringBuilder();
message.Append("Hi We have these flights for you: ");
message.Append(flights);
message.Append(" . Which one do you want?");

Excel Formula to SUMIF date falls in particular month

Try this instead:

  =SUM(IF(MONTH($A$2:$A$6)=1,$B$2:$B$6,0))

It's an array formula, so you will need to enter it with the Control-Shift-Enter key combination.

Here's how the formula works.

  1. MONTH($A$2:$A$6) creates an array of numeric values of the month for the dates in A2:A6, that is,
    {1, 1, 1, 2, 2}.
  2. Then the comparison {1, 1, 1, 2, 2}= 1 produces the array {TRUE, TRUE, TRUE, FALSE, FALSE}, which comprises the condition for the IF statement.
  3. The IF statement then returns an array of values, with {430, 96, 400.. for the values of the sum ranges where the month value equals 1 and ..0,0} where the month value does not equal 1.
  4. That array {430, 96, 400, 0, 0} is then summed to get the answer you are looking for.

This is essentially equivalent to what the SUMIF and SUMIFs functions do. However, neither of those functions support the kind of calculation you tried to include in the conditional.

It's also possible to drop the IF completely. Since TRUE and FALSE can also be treated as 1 and 0, this formula--=SUM((MONTH($A$2:$A$6)=1)*$B$2:$B$6)--also works.

Heads up: This does not work in Google Spreadsheets

How can I count text lines inside an DOM element? Can I?

Check out the function getClientRects() which can be used to count the number of lines in an element. Here is an example of how to use it.

var message_lines = $("#message_container")[0].getClientRects();

It returns a javascript DOM object. The amount of lines can be known by doing this:

var amount_of_lines = message_lines.length;

It can return the height of each line, and more. See the full array of things it can do by adding this to your script, then looking in your console log.

console.log("");
console.log("message_lines");
console.log(".............................................");
console.dir(message_lines);
console.log("");

Though a few things to note is it only works if the containing element is inline, however you can surround the containing inline element with a block element to control the width like so:

<div style="width:300px;" id="block_message_container">
<div style="display:inline;" id="message_container">
..Text of the post..
</div>
</div>

Though I don't recommend hard coding the style like that. It's just for example purposes.

What is the difference between the | and || or operators?

The single pipe, |, is one of the bitwise operators.

From Wikipedia:

In the C programming language family, the bitwise OR operator is "|" (pipe). Again, this operator must not be confused with its Boolean "logical or" counterpart, which treats its operands as Boolean values, and is written "||" (two pipes).

Add space between cells (td) using css

Mine is:

border-spacing: 10px;
border-collapse: separate;

Test only if variable is not null in if statement

I don't believe the expression is sensical as it is.

Elvis means "if truthy, use the value, else use this other thing."

Your "other thing" is a closure, and the value is status != null, neither of which would seem to be what you want. If status is null, Elvis says true. If it's not, you get an extra layer of closure.

Why can't you just use:

(it.description == desc) && ((status == null) || (it.status == status))

Even if that didn't work, all you need is the closure to return the appropriate value, right? There's no need to create two separate find calls, just use an intermediate variable.

Save Dataframe to csv directly to s3 Python

You can use:

from io import StringIO # python3; python2: BytesIO 
import boto3

bucket = 'my_bucket_name' # already created on S3
csv_buffer = StringIO()
df.to_csv(csv_buffer)
s3_resource = boto3.resource('s3')
s3_resource.Object(bucket, 'df.csv').put(Body=csv_buffer.getvalue())

How to set up a cron job to run an executable every hour?

The solution to solve this is to find out why you're getting the segmentation fault, and fix that.

When should I use the Visitor Design Pattern?

Visitor

Visitor allows one to add new virtual functions to a family of classes without modifying the classes themselves; instead, one creates a visitor class that implements all of the appropriate specializations of the virtual function

Visitor structure:

enter image description here

Use Visitor pattern if:

  1. Similar operations have to be performed on objects of different types grouped in a structure
  2. You need to execute many distinct and unrelated operations. It separates Operation from objects Structure
  3. New operations have to be added without change in object structure
  4. Gather related operations into a single class rather than force you to change or derive classes
  5. Add functions to class libraries for which you either do not have the source or cannot change the source

Even though Visitor pattern provides flexibility to add new operation without changing the existing code in Object, this flexibility has come with a drawback.

If a new Visitable object has been added, it requires code changes in Visitor & ConcreteVisitor classes. There is a workaround to address this issue : Use reflection, which will have impact on performance.

Code snippet:

import java.util.HashMap;

interface Visitable{
    void accept(Visitor visitor);
}

interface Visitor{
    void logGameStatistics(Chess chess);
    void logGameStatistics(Checkers checkers);
    void logGameStatistics(Ludo ludo);    
}
class GameVisitor implements Visitor{
    public void logGameStatistics(Chess chess){
        System.out.println("Logging Chess statistics: Game Completion duration, number of moves etc..");    
    }
    public void logGameStatistics(Checkers checkers){
        System.out.println("Logging Checkers statistics: Game Completion duration, remaining coins of loser");    
    }
    public void logGameStatistics(Ludo ludo){
        System.out.println("Logging Ludo statistics: Game Completion duration, remaining coins of loser");    
    }
}

abstract class Game{
    // Add game related attributes and methods here
    public Game(){

    }
    public void getNextMove(){};
    public void makeNextMove(){}
    public abstract String getName();
}
class Chess extends Game implements Visitable{
    public String getName(){
        return Chess.class.getName();
    }
    public void accept(Visitor visitor){
        visitor.logGameStatistics(this);
    }
}
class Checkers extends Game implements Visitable{
    public String getName(){
        return Checkers.class.getName();
    }
    public void accept(Visitor visitor){
        visitor.logGameStatistics(this);
    }
}
class Ludo extends Game implements Visitable{
    public String getName(){
        return Ludo.class.getName();
    }
    public void accept(Visitor visitor){
        visitor.logGameStatistics(this);
    }
}

public class VisitorPattern{
    public static void main(String args[]){
        Visitor visitor = new GameVisitor();
        Visitable games[] = { new Chess(),new Checkers(), new Ludo()};
        for (Visitable v : games){
            v.accept(visitor);
        }
    }
}

Explanation:

  1. Visitable (Element) is an interface and this interface method has to be added to a set of classes.
  2. Visitor is an interface, which contains methods to perform an operation on Visitable elements.
  3. GameVisitor is a class, which implements Visitor interface ( ConcreteVisitor).
  4. Each Visitable element accept Visitor and invoke a relevant method of Visitor interface.
  5. You can treat Game as Element and concrete games like Chess,Checkers and Ludo as ConcreteElements.

In above example, Chess, Checkers and Ludo are three different games ( and Visitable classes). On one fine day, I have encountered with a scenario to log statistics of each game. So without modifying individual class to implement statistics functionality, you can centralise that responsibility in GameVisitor class, which does the trick for you without modifying the structure of each game.

output:

Logging Chess statistics: Game Completion duration, number of moves etc..
Logging Checkers statistics: Game Completion duration, remaining coins of loser
Logging Ludo statistics: Game Completion duration, remaining coins of loser

Refer to

oodesign article

sourcemaking article

for more details

Decorator

pattern allows behaviour to be added to an individual object, either statically or dynamically, without affecting the behaviour of other objects from the same class

Related posts:

Decorator Pattern for IO

When to Use the Decorator Pattern?

Border Radius of Table is not working

To use border radius I have a border radius of 20px in the table, and then put the border radius on the first child of the table header (th) and the last child of the table header.

table {
  border-collapse: collapse;
  border-radius:20px;
  padding: 10px;
}

table th:first-child {
  /* border-radius = top left, top right, bottom right, bottom left */
    border-radius: 20px 0 0 0; /* curves the top left */
    padding-left: 15px;
}

table th:last-child {
    border-radius: 0 20px 0 0; /* curves the top right */
}

This however will not work if this is done with table data (td) because it will add a curve onto each table row. This is not a problem if you only have 2 rows in your table but any additional ones will add curves onto the inner rows too. You only want these curves on the outside of the table. So for this, add an id to your last row. Then you can apply the curves to them.

/* curves the first tableData in the last row */

#lastRow td:first-child {
    border-radius: 0 0 0 20px; /* bottom left curve */
}

/* curves the last tableData in the last row */

#lastRow td:last-child {
    border-radius: 0 0 20px 0; /* bottom right curve */
}

How to run cron job every 2 hours

0 */1 * * * “At minute 0 past every hour.”

0 */2 * * * “At minute 0 past every 2nd hour.”

This is the proper way to set cronjobs for every hr.

Regular expression [Any number]

UPDATE: for your updated question

variable.match(/\[[0-9]+\]/);

Try this:

variable.match(/[0-9]+/);    // for unsigned integers
variable.match(/[-0-9]+/);   // for signed integers
variable.match(/[-.0-9]+/);  // for signed float numbers

Hope this helps!

Ignoring new fields on JSON objects using Jackson

Jackson provides an annotation that can be used on class level (JsonIgnoreProperties).

Add the following to the top of your class (not to individual methods):

@JsonIgnoreProperties(ignoreUnknown = true)
public class Foo {
    ...
}

Depending on the jackson version you are using you would have to use a different import in the current version it is:

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;

in older versions it has been:

import org.codehaus.jackson.annotate.JsonIgnoreProperties;

Graphical user interface Tutorial in C

The two most usual choices are GTK+, which has documentation links here, and is mostly used with C; or Qt which has documentation here and is more used with C++.

I posted these two as you do not specify an operating system and these two are pretty cross-platform.

Changing the cursor in WPF sometimes works, sometimes doesn't

Do you need the cursor to be a "wait" cursor only when it's over that particular page/usercontrol? If not, I'd suggest using Mouse.OverrideCursor:

Mouse.OverrideCursor = Cursors.Wait;
try
{
    // do stuff
}
finally
{
    Mouse.OverrideCursor = null;
}

This overrides the cursor for your application rather than just for a part of its UI, so the problem you're describing goes away.

detect back button click in browser

best way I know

         window.onbeforeunload = function (e) {
            var e = e || window.event;
            var msg = "Do you really want to leave this page?"

            // For IE and Firefox
            if (e) {
                e.returnValue = msg;
            }

            // For Safari / chrome
            return msg;
         };

DLL and LIB files - what and why?

One other difference lies in the performance.

As the DLL is loaded at runtime by the .exe(s), the .exe(s) and the DLL work with shared memory concept and hence the performance is low relatively to static linking.

On the other hand, a .lib is code that is linked statically at compile time into every process that requests. Hence the .exe(s) will have single memory, thus increasing the performance of the process.

Conditional HTML Attributes using Razor MVC3

You didn't hear it from me, the PM for Razor, but in Razor 2 (Web Pages 2 and MVC 4) we'll have conditional attributes built into Razor(as of MVC 4 RC tested successfully), so you can just say things like this...

<input type="text" id="@strElementID" class="@strCSSClass" />

If strCSSClass is null then the class attribute won't render at all.

SSSHHH...don't tell. :)

What is the purpose of the HTML "no-js" class?

The no-js class gets removed by a javascript script, so you can modify/display/hide things using css if js is disabled.

Count how many rows have the same value

SELECT sum(num) WHERE num = 1;

Default Xmxsize in Java 8 (max heap size)

As of 8, May, 2019:

JVM heap size depends on system configuration, meaning:

a) client jvm vs server jvm

b) 32bit vs 64bit.

Links:

1) updation from J2SE5.0: https://docs.oracle.com/javase/6/docs/technotes/guides/vm/gc-ergonomics.html
2) brief answer: https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/ergonomics.html
3) detailed answer: https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/parallel.html#default_heap_size
4) client vs server: https://www.javacodegeeks.com/2011/07/jvm-options-client-vs-server.html

Summary: (Its tough to understand from the above links. So summarizing them here)

1) Default maximum heap size for Client jvm is 256mb (there is an exception, read from links above).

2) Default maximum heap size for Server jvm of 32bit is 1gb and of 64 bit is 32gb (again there are exceptions here too. Kindly read that from the links).

So default maximum jvm heap size is: 256mb or 1gb or 32gb depending on VM, above.

How can I catch a ctrl-c event?

For a Windows console app, you want to use SetConsoleCtrlHandler to handle CTRL+C and CTRL+BREAK.

See here for an example.

Python list of dictionaries search

I found this thread when I was searching for an answer to the same question. While I realize that it's a late answer, I thought I'd contribute it in case it's useful to anyone else:

def find_dict_in_list(dicts, default=None, **kwargs):
    """Find first matching :obj:`dict` in :obj:`list`.

    :param list dicts: List of dictionaries.
    :param dict default: Optional. Default dictionary to return.
        Defaults to `None`.
    :param **kwargs: `key=value` pairs to match in :obj:`dict`.

    :returns: First matching :obj:`dict` from `dicts`.
    :rtype: dict

    """

    rval = default
    for d in dicts:
        is_found = False

        # Search for keys in dict.
        for k, v in kwargs.items():
            if d.get(k, None) == v:
                is_found = True

            else:
                is_found = False
                break

        if is_found:
            rval = d
            break

    return rval


if __name__ == '__main__':
    # Tests
    dicts = []
    keys = 'spam eggs shrubbery knight'.split()

    start = 0
    for _ in range(4):
        dct = {k: v for k, v in zip(keys, range(start, start+4))}
        dicts.append(dct)
        start += 4

    # Find each dict based on 'spam' key only.  
    for x in range(len(dicts)):
        spam = x*4
        assert find_dict_in_list(dicts, spam=spam) == dicts[x]

    # Find each dict based on 'spam' and 'shrubbery' keys.
    for x in range(len(dicts)):
        spam = x*4
        assert find_dict_in_list(dicts, spam=spam, shrubbery=spam+2) == dicts[x]

    # Search for one correct key, one incorrect key:
    for x in range(len(dicts)):
        spam = x*4
        assert find_dict_in_list(dicts, spam=spam, shrubbery=spam+1) is None

    # Search for non-existent dict.
    for x in range(len(dicts)):
        spam = x+100
        assert find_dict_in_list(dicts, spam=spam) is None

How do I see what character set a MySQL database / table / column is?

I always just look at SHOW CREATE TABLE mydatabase.mytable.

For the database, it appears you need to look at SELECT DEFAULT_CHARACTER_SET_NAME FROM information_schema.SCHEMATA.

How do I rename a MySQL schema?

If you're on the Model Overview page you get a tab with the schema. If you rightclick on that tab you get an option to "edit schema". From there you can rename the schema by adding a new name, then click outside the field. This goes for MySQL Workbench 5.2.30 CE

Edit: On the model overview it's under Physical Schemata

Screenshot:

enter image description here

Adding Only Untracked Files

git add . (add all files in this directory)

git add -all (add all files in all directories)

git add -N can be helpful for for listing which ones for later....

PHP - Indirect modification of overloaded property

I was receiving this notice for doing this:

$var = reset($myClass->my_magic_property);

This fixed it:

$tmp = $myClass->my_magic_property;
$var = reset($tmp);

How to style a clicked button in CSS

There are three states of button

  • Normal : You can select like this button
  • Hover : You can select like this button:hover
  • Pressed/Clicked : You can select like this button:active

Normal:

.button
 {
     //your css
 }

Active

 .button:active
{
        //your css
}

Hover

 .button:hover
{
        //your css
}

SNIPPET:

Use :active to style the active state of button.

_x000D_
_x000D_
button:active{_x000D_
   background-color:red;_x000D_
}
_x000D_
<button>Click Me</button>
_x000D_
_x000D_
_x000D_

IndentationError: unexpected unindent WHY?

It's because you have:

def readTTable(fname):
    try:

without a matching except block after the try: block. Every try must have at least one matching except.

See the Errors and Exceptions section of the Python tutorial.

How to set connection timeout with OkHttp

It's changed now. Replace .Builder() with .newBuilder()

As of okhttp:3.9.0 the code goes as follows:

OkHttpClient okHttpClient = new OkHttpClient()
    .newBuilder()
    .connectTimeout(10,TimeUnit.SECONDS)
    .writeTimeout(10,TimeUnit.SECONDS)
    .readTimeout(30,TimeUnit.SECONDS)
    .build();

append new row to old csv file python

Are you opening the file with mode of 'a' instead of 'w'?

See Reading and Writing Files in the python docs

7.2. Reading and Writing Files

open() returns a file object, and is most commonly used with two arguments: open(filename, mode).

>>> f = open('workfile', 'w')
>>> print f <open file 'workfile', mode 'w' at 80a0960>

The first argument is a string containing the filename. The second argument is another string containing a few characters describing the way in which the file will be used. mode can be 'r' when the file will only be read, 'w' for only writing (an existing file with the same name will be erased), and 'a' opens the file for appending; any data written to the file is automatically added to the end. 'r+' opens the file for both reading and writing. The mode argument is optional; 'r' will be assumed if it’s omitted.

On Windows, 'b' appended to the mode opens the file in binary mode, so there are also modes like 'rb', 'wb', and 'r+b'. Python on Windows makes a distinction between text and binary files; the end-of-line characters in text files are automatically altered slightly when data is read or written. This behind-the-scenes modification to file data is fine for ASCII text files, but it’ll corrupt binary data like that in JPEG or EXE files. Be very careful to use binary mode when reading and writing such files. On Unix, it doesn’t hurt to append a 'b' to the mode, so you can use it platform-independently for all binary files.

The definitive guide to form-based website authentication

I would like to add one very important comment: -

  • "In a corporate, intra- net setting," most if not all of the foregoing might not apply!

Many corporations deploy "internal use only" websites which are, effectively, "corporate applications" that happen to have been implemented through URLs. These URLs can (supposedly ...) only be resolved within "the company's internal network." (Which network magically includes all VPN-connected 'road warriors.')

When a user is dutifully-connected to the aforesaid network, their identity ("authentication") is [already ...] "conclusively known," as is their permission ("authorization") to do certain things ... such as ... "to access this website."

This "authentication + authorization" service can be provided by several different technologies, such as LDAP (Microsoft OpenDirectory), or Kerberos.

From your point-of-view, you simply know this: that anyone who legitimately winds-up at your website must be accompanied by [an environment-variable magically containing ...] a "token." (i.e. The absence of such a token must be immediate grounds for 404 Not Found.)

The token's value makes no sense to you, but, should the need arise, "appropriate means exist" by which your website can "[authoritatively] ask someone who knows (LDAP... etc.)" about any and every(!) question that you may have. In other words, you do not avail yourself of any "home-grown logic." Instead, you inquire of The Authority and implicitly trust its verdict.

Uh huh ... it's quite a mental-switch from the "wild-and-wooly Internet."

The total number of locks exceeds the lock table size

Fixing Error code 1206: The number of locks exceeds the lock table size.

In my case, I work with MySQL Workbench (5.6.17) running on Windows with WampServer 2.5.

For Windows/WampServer you have to edit the my.ini file (not the my.cnf file)

To locate this file go to Menu Server/Server Status (in MySQL Workbench) and look under Server Directories/ Base Directory

MySQL Server - Server Status

In my.ini file there are defined sections for different settings, look for section [mysqld] (create it if it does not exist) and add the command: innodb_buffer_pool_size=4G

[mysqld]
innodb_buffer_pool_size=4G

The size of the buffer_pool file will depend on your specific machine, in most cases, 2G or 4G will fix the problem.

Remember to restart the server so it takes the new configuration, it corrected the problem for me.

Hope it helps!

How to extract base URL from a string in JavaScript?

To get the origin of any url, including paths within a website (/my/path) or schemaless (//example.com/my/path), or full (http://example.com/my/path) I put together a quick function.

In the snippet below, all three calls should log https://stacksnippets.net.

_x000D_
_x000D_
function getOrigin(url)_x000D_
{_x000D_
  if(/^\/\//.test(url))_x000D_
  { // no scheme, use current scheme, extract domain_x000D_
    url = window.location.protocol + url;_x000D_
  }_x000D_
  else if(/^\//.test(url))_x000D_
  { // just path, use whole origin_x000D_
    url = window.location.origin + url;_x000D_
  }_x000D_
  return url.match(/^([^/]+\/\/[^/]+)/)[0];_x000D_
}_x000D_
_x000D_
console.log(getOrigin('https://stacksnippets.net/my/path'));_x000D_
console.log(getOrigin('//stacksnippets.net/my/path'));_x000D_
console.log(getOrigin('/my/path'));
_x000D_
_x000D_
_x000D_

Find all elements with a certain attribute value in jquery

It's not called a tag; what you're looking for is called an html attribute.

$('div[imageId="imageN"]').each(function(i,el){
  $(el).html('changes');
  //do what ever you wish to this object :) 
});

How to draw a filled circle in Java?

public void paintComponent(Graphics g) {
   super.paintComponent(g);
   Graphics2D g2d = (Graphics2D)g;
   // Assume x, y, and diameter are instance variables.
   Ellipse2D.Double circle = new Ellipse2D.Double(x, y, diameter, diameter);
   g2d.fill(circle);
   ...
}

Here are some docs about paintComponent (link).

You should override that method in your JPanel and do something similar to the code snippet above.

In your ActionListener you should specify x, y, diameter and call repaint().

How to set image to fit width of the page using jsPDF?

        var width = doc.internal.pageSize.width;    
        var height = doc.internal.pageSize.height;

Get the decimal part from a double

Here's an extension method I wrote for a similar situation. My application would receive numbers in the format of 2.3 or 3.11 where the integer component of the number represented years and the fractional component represented months.

// Sample Usage
int years, months;
double test1 = 2.11;
test1.Split(out years, out months);
// years = 2 and months = 11

public static class DoubleExtensions
{
    public static void Split(this double number, out int years, out int months)
    {
        years = Convert.ToInt32(Math.Truncate(number));

        double tempMonths = Math.Round(number - years, 2);
        while ((tempMonths - Math.Floor(tempMonths)) > 0 && tempMonths != 0) tempMonths *= 10;
        months = Convert.ToInt32(tempMonths);
    }
}

how to move elasticsearch data from one server to another

Use ElasticDump

1) yum install epel-release

2) yum install nodejs

3) yum install npm

4) npm install elasticdump

5) cd node_modules/elasticdump/bin

6)

./elasticdump \

  --input=http://192.168.1.1:9200/original \

  --output=http://192.168.1.2:9200/newCopy \

  --type=data

Convert Json String to C# Object List

public static class Helper
{
    public static string AsJsonList<T>(List<T> tt)
    {
        return new JavaScriptSerializer().Serialize(tt);
    }
    public static string AsJson<T>(T t)
    {
        return new JavaScriptSerializer().Serialize(t);
    }
    public static List<T> AsObjectList<T>(string tt)
    {
        return new JavaScriptSerializer().Deserialize<List<T>>(tt);
    }
    public static T AsObject<T>(string t)
    {
        return new JavaScriptSerializer().Deserialize<T>(t);
    }
}

Why use static_cast<int>(x) instead of (int)x?

The main reason is that classic C casts make no distinction between what we call static_cast<>(), reinterpret_cast<>(), const_cast<>(), and dynamic_cast<>(). These four things are completely different.

A static_cast<>() is usually safe. There is a valid conversion in the language, or an appropriate constructor that makes it possible. The only time it's a bit risky is when you cast down to an inherited class; you must make sure that the object is actually the descendant that you claim it is, by means external to the language (like a flag in the object). A dynamic_cast<>() is safe as long as the result is checked (pointer) or a possible exception is taken into account (reference).

A reinterpret_cast<>() (or a const_cast<>()) on the other hand is always dangerous. You tell the compiler: "trust me: I know this doesn't look like a foo (this looks as if it isn't mutable), but it is".

The first problem is that it's almost impossible to tell which one will occur in a C-style cast without looking at large and disperse pieces of code and knowing all the rules.

Let's assume these:

class CDerivedClass : public CMyBase {...};
class CMyOtherStuff {...} ;

CMyBase  *pSomething; // filled somewhere

Now, these two are compiled the same way:

CDerivedClass *pMyObject;
pMyObject = static_cast<CDerivedClass*>(pSomething); // Safe; as long as we checked

pMyObject = (CDerivedClass*)(pSomething); // Same as static_cast<>
                                     // Safe; as long as we checked
                                     // but harder to read

However, let's see this almost identical code:

CMyOtherStuff *pOther;
pOther = static_cast<CMyOtherStuff*>(pSomething); // Compiler error: Can't convert

pOther = (CMyOtherStuff*)(pSomething);            // No compiler error.
                                                  // Same as reinterpret_cast<>
                                                  // and it's wrong!!!

As you can see, there is no easy way to distinguish between the two situations without knowing a lot about all the classes involved.

The second problem is that the C-style casts are too hard to locate. In complex expressions it can be very hard to see C-style casts. It is virtually impossible to write an automated tool that needs to locate C-style casts (for example a search tool) without a full blown C++ compiler front-end. On the other hand, it's easy to search for "static_cast<" or "reinterpret_cast<".

pOther = reinterpret_cast<CMyOtherStuff*>(pSomething);
      // No compiler error.
      // but the presence of a reinterpret_cast<> is 
      // like a Siren with Red Flashing Lights in your code.
      // The mere typing of it should cause you to feel VERY uncomfortable.

That means that, not only are C-style casts more dangerous, but it's a lot harder to find them all to make sure that they are correct.

Ignore case in Python strings

There's no built in equivalent to that function you want.

You can write your own function that converts to .lower() each character at a time to avoid duplicating both strings, but I'm sure it will very cpu-intensive and extremely inefficient.

Unless you are working with extremely long strings (so long that can cause a memory problem if duplicated) then I would keep it simple and use

str1.lower() == str2.lower()

You'll be ok

How do you clear a slice in Go?

I was looking into this issue a bit for my own purposes; I had a slice of structs (including some pointers) and I wanted to make sure I got it right; ended up on this thread, and wanted to share my results.

To practice, I did a little go playground: https://play.golang.org/p/9i4gPx3lnY

which evals to this:

package main

import "fmt"

type Blah struct {
    babyKitten int
    kittenSays *string
}

func main() {
    meow := "meow"
    Blahs := []Blah{}
    fmt.Printf("Blahs: %v\n", Blahs)
    Blahs = append(Blahs, Blah{1, &meow})
    fmt.Printf("Blahs: %v\n", Blahs)
    Blahs = append(Blahs, Blah{2, &meow})
    fmt.Printf("Blahs: %v\n", Blahs)
    //fmt.Printf("kittenSays: %v\n", *Blahs[0].kittenSays)
    Blahs = nil
    meow2 := "nyan"
    fmt.Printf("Blahs: %v\n", Blahs)
    Blahs = append(Blahs, Blah{1, &meow2})
    fmt.Printf("Blahs: %v\n", Blahs)
    fmt.Printf("kittenSays: %v\n", *Blahs[0].kittenSays)
}

Running that code as-is will show the same memory address for both "meow" and "meow2" variables as being the same:

Blahs: []
Blahs: [{1 0x1030e0c0}]
Blahs: [{1 0x1030e0c0} {2 0x1030e0c0}]
Blahs: []
Blahs: [{1 0x1030e0f0}]
kittenSays: nyan

which I think confirms that the struct is garbage collected. Oddly enough, uncommenting the commented print line, will yield different memory addresses for the meows:

Blahs: []
Blahs: [{1 0x1030e0c0}]
Blahs: [{1 0x1030e0c0} {2 0x1030e0c0}]
kittenSays: meow
Blahs: []
Blahs: [{1 0x1030e0f8}]
kittenSays: nyan

I think this may be due to the print being deferred in some way (?), but interesting illustration of some memory mgmt behavior, and one more vote for:

[]MyStruct = nil

What is the difference between signed and unsigned variables?

Unsigned variables can only be positive numbers, because they lack the ability to indicate that they are negative.

This ability is called the 'sign' or 'signing bit'.

A side effect is that without a signing bit, they have one more bit that can be used to represent the number, doubling the maximum number it can represent.

How to reset a select element with jQuery

This function should work for all types of select (multiple, select, select2):

$.fn.Reset_List_To_Default_Value = function()
{
    $.each($(this), function(index, el) {
        var Founded = false;

        $(this).find('option').each(function(i, opt) {
            if(opt.defaultSelected){
                opt.selected = true;
                Founded = true;
            }
        });

        if(!Founded)
        {
            if($(this).attr('multiple'))
            {
                $(this).val([]);
            }
            else
            {
                $(this).val("");
            }
        }
        $(this).trigger('change');
    });
}

To use it just call:

$('select').Reset_List_To_Default_Value();

How to get a user's time zone?

NSTimeZone *timeZone = [NSTimeZone localTimeZone];
NSString *tzName = [timeZone name];

The name will be something like "Australia/Sydney", or "Europe/Lisbon".

Since it sounds like you might only care about the continent, that might be all you need.

"Invalid form control" only in Google Chrome

It will show that message if you have code like this:

<form>
  <div style="display: none;">
    <input name="test" type="text" required/>
  </div>

  <input type="submit"/>
</form>

solution to this problem will depend on how the site should work

for example if you don't want the form to submit unless this field is required you should disable the submit button

so the js code to show the div should enable the submit button as well

you can hide the button too (should be disabled and hidden because if it's hidden but not disabled the user can submit the form with others way like press enter in any other field but if the button is disabled this won't happen

if you want the form to submit if the div is hidden you should disable any required input inside it and enable the inputs while you are showing the div

if someone need the codes to do so you should tell me exactly what you need

Angularjs ng-model doesn't work inside ng-if

You can do it like this and you mod function will work perfect let me know if you want a code pen

  <div ng-repeat="icon in icons">                   
                <div class="row" ng-if="$index % 3 == 0 ">
                    <i class="col col-33 {{icons[$index + n].icon}} custom-icon"></i>
                    <i class="col col-33 {{icons[$index + n + 1].icon}} custom-icon"></i>
                    <i class="col col-33 {{icons[$index + n + 2].icon}} custom-icon"></i>
                </div>
         </div>

Remove scroll bar track from ScrollView in Android

By using below, solved the problem

android:scrollbarThumbVertical="@null"

How to create file object from URL object (image)

Since Java 7

File file = Paths.get(url.toURI()).toFile();

offsetting an html anchor to adjust for fixed header

Adding to Ziav's answer (with thanks to Alexander Savin), I need to be using the old-school <a name="...">...</a> as we're using <div id="...">...</div> for another purpose in our code. I had some display issues using display: inline-block -- the first line of every <p> element was turning out to be slightly right-indented (on both Webkit and Firefox browsers). I ended up trying other display values and display: table-caption works perfectly for me.

.anchor {
  padding-top: 60px;
  margin-top: -60px;
  display: table-caption;
}

How can I find out the total physical memory (RAM) of my linux box suitable to be parsed by a shell script?

Total online memory

Calculate the total online memory using the sys-fs.

totalmem=0;
for mem in /sys/devices/system/memory/memory*; do
  [[ "$(cat ${mem}/online)" == "1" ]] \
    && totalmem=$((totalmem+$((0x$(cat /sys/devices/system/memory/block_size_bytes)))));
done

#one-line code
totalmem=0; for mem in /sys/devices/system/memory/memory*; do [[ "$(cat ${mem}/online)" == "1" ]] && totalmem=$((totalmem+$((0x$(cat /sys/devices/system/memory/block_size_bytes))))); done

echo ${totalmem} bytes
echo $((totalmem/1024**3)) GB

Example output for 4 GB system:

4294967296 bytes
4 GB

Explanation

/sys/devices/system/memory/block_size_bytes

Number of bytes in a memory block (hex value). Using 0x in front of the value makes sure it's properly handled during the calculation.

/sys/devices/system/memory/memory*

Iterating over all available memory blocks to verify they are online and add the calculated block size to totalmem if they are.

[[ "$(cat ${mem}/online)" == "1" ]] &&

You can change or remove this if you prefer another memory state.

How to add "required" attribute to mvc razor viewmodel text input editor

@Erik's answer didn't fly for me.

Following did:

 @Html.TextBoxFor(m => m.ShortName,  new { data_val_required = "You need me" })

plus doing this manually under field I had to add error message container

@Html.ValidationMessageFor(m => m.ShortName, null, new { @class = "field-validation-error", data_valmsg_for = "ShortName" })

Hope this saves you some time.

C++11 reverse range-based for-loop

Actually Boost does have such adaptor: boost::adaptors::reverse.

#include <list>
#include <iostream>
#include <boost/range/adaptor/reversed.hpp>

int main()
{
    std::list<int> x { 2, 3, 5, 7, 11, 13, 17, 19 };
    for (auto i : boost::adaptors::reverse(x))
        std::cout << i << '\n';
    for (auto i : x)
        std::cout << i << '\n';
}

MySQL INNER JOIN Alias

Use a seperate column to indicate the join condition

SELECT  t.importid, 
        case 
            when t.importid = g.home 
            then 'home' 
            else 'away' 
        end as join_condition, 
        g.network, 
        g.date_start 
FROM    game g
INNER JOIN team t ON (t.importid = g.home OR t.importid = g.away)
ORDER BY date_start DESC 
LIMIT 7

Indexes of all occurrences of character in a string

With Java9, one can make use of the iterate(int seed, IntPredicate hasNext,IntUnaryOperator next) as follows:-

List<Integer> indexes = IntStream
          .iterate(word.indexOf(c), index -> index >= 0, index -> word.indexOf(c, index + 1))
          .boxed()
          .collect(Collectors.toList());
System.out.printlnt(indexes);

Available text color classes in Bootstrap

You can use text classes:

.text-primary
.text-secondary
.text-success
.text-danger
.text-warning
.text-info
.text-light
.text-dark
.text-muted
.text-white

use text classes in any tag where needed.

<p class="text-primary">.text-primary</p>
<p class="text-secondary">.text-secondary</p>
<p class="text-success">.text-success</p>
<p class="text-danger">.text-danger</p>
<p class="text-warning">.text-warning</p>
<p class="text-info">.text-info</p>
<p class="text-light bg-dark">.text-light</p>
<p class="text-dark">.text-dark</p>
<p class="text-muted">.text-muted</p>
<p class="text-white bg-dark">.text-white</p>

You can add your own classes or modify above classes as your requirement.

Why SQL Server throws Arithmetic overflow error converting int to data type numeric?

Precision and scale are often misunderstood. In numeric(3,2) you want 3 digits overall, but 2 to the right of the decimal. If you want 15 => 15.00 so the leading 1 causes the overflow (since if you want 2 digits to the right of the decimal, there is only room on the left for one more digit). With 4,2 there is no problem because all 4 digits fit.

Override element.style using CSS

As per my knowledge Inline sytle comes first so css class should not work.

Use Jquery as

$(document).ready(function(){

   $("#demoFour li").css("display","inline");
  });

You can also try 

#demoFour li { display:inline !important;}

Oracle date function for the previous month

The trunc() function truncates a date to the specified time period; so trunc(sysdate,'mm') would return the beginning of the current month. You can then use the add_months() function to get the beginning of the previous month, something like this:

select count(distinct switch_id)   
  from [email protected]  
 where dealer_name =  'XXXX'    
   and creation_date >= add_months(trunc(sysdate,'mm'),-1) 
   and creation_date < trunc(sysdate, 'mm')

As a little side not you're not explicitly converting to a date in your original query. Always do this, either using a date literal, e.g. DATE 2012-08-31, or the to_date() function, for example to_date('2012-08-31','YYYY-MM-DD'). If you don't then you are bound to get this wrong at some point.

You would not use sysdate - 15 as this would provide the date 15 days before the current date, which does not seem to be what you are after. It would also include a time component as you are not using trunc().


Just as a little demonstration of what trunc(<date>,'mm') does:

select sysdate
     , case when trunc(sysdate,'mm') > to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
             then 1 end as gt
     , case when trunc(sysdate,'mm') < to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
             then 1 end as lt
     , case when trunc(sysdate,'mm') = to_date('20120901 00:00:00','yyyymmdd hh24:mi:ss')
             then 1 end as eq
  from dual
       ;

SYSDATE                   GT         LT         EQ
----------------- ---------- ---------- ----------
20120911 19:58:51                                1

How to save a figure in MATLAB from the command line?

I don't think you can save it without it appearing, but just for saving in multiple formats use the print command. See the answer posted here: Save an imagesc output in Matlab

How can I get a collection of keys in a JavaScript dictionary?

To loop through the "dictionary" (we call it object in JavaScript), use a for in loop:

for(var key in driversCounter) {
    if(driversCounter.hasOwnProperty(key)) {
        // key                 = keys,  left of the ":"
        // driversCounter[key] = value, right of the ":"
    }
}

Adding Lombok plugin to IntelliJ project

To install the plugin manually, try:

  1. Download Lombok zip file (ensure Lombok matches the IDE version).
  2. Select Preferences Plugins Install Plugins from Disk.

IntelliJ Plugin Preferences Dialog

Excel: Search for a list of strings within a particular string using array formulas?

  1. Arange your word list with delimiter which never occures in the words, f.e. |
  2. swap arguments in find call - we want search if cell value is matching one of the words in pattern string {=FIND("cell I want to search","list of words I want to search for")}
  3. if the patterns are similar, there is a risk of getting more results than wanted, we restrict just correct results via adding &"|" to the cell value tested (works well with array formulas) cell G3 could contain: {=SUM(FIND($A$1:$A$100&"|";A3))} this ensures spreadsheet will compare strings like "cellvlaue|" againts "pattern1|", "pattern2|" etc. which sorts out conflicts like pattern1="newly added", pattern2="added" (sum of all cells matching "added" would be too high, including the target values for cells matching "newly added", which would be a logical error)

MySQL Insert with While Loop

You cannot use WHILE like that; see: mysql DECLARE WHILE outside stored procedure how?

You have to put your code in a stored procedure. Example:

CREATE PROCEDURE myproc()
BEGIN
    DECLARE i int DEFAULT 237692001;
    WHILE i <= 237692004 DO
        INSERT INTO mytable (code, active, total) VALUES (i, 1, 1);
        SET i = i + 1;
    END WHILE;
END

Fiddle: http://sqlfiddle.com/#!2/a4f92/1

Alternatively, generate a list of INSERT statements using any programming language you like; for a one-time creation, it should be fine. As an example, here's a Bash one-liner:

for i in {2376921001..2376921099}; do echo "INSERT INTO mytable (code, active, total) VALUES ($i, 1, 1);"; done

By the way, you made a typo in your numbers; 2376921001 has 10 digits, 237692200 only 9.

Java regex capturing groups indexes

Parenthesis () are used to enable grouping of regex phrases.

The group(1) contains the string that is between parenthesis (.*) so .* in this case

And group(0) contains whole matched string.

If you would have more groups (read (...) ) it would be put into groups with next indexes (2, 3 and so on).

How to modify JsonNode in Java?

Adding an answer as some others have upvoted in the comments of the accepted answer they are getting this exception when attempting to cast to ObjectNode (myself included):

Exception in thread "main" java.lang.ClassCastException: 
com.fasterxml.jackson.databind.node.TextNode cannot be cast to com.fasterxml.jackson.databind.node.ObjectNode

The solution is to get the 'parent' node, and perform a put, effectively replacing the entire node, regardless of original node type.

If you need to "modify" the node using the existing value of the node:

  1. get the value/array of the JsonNode
  2. Perform your modification on that value/array
  3. Proceed to call put on the parent.

Code, where the goal is to modify subfield, which is the child node of NodeA and Node1:

JsonNode nodeParent = someNode.get("NodeA")
                .get("Node1");

// Manually modify value of 'subfield', can only be done using the parent.
((ObjectNode) nodeParent).put('subfield', "my-new-value-here");

Credits:

I got this inspiration from here, thanks to wassgreen@

Showing all errors and warnings

Straight from the php.ini file:

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; Error handling and logging ;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

; This directive informs PHP of which errors, warnings and notices you would like
; it to take action for. The recommended way of setting values for this
; directive is through the use of the error level constants and bitwise
; operators. The error level constants are below here for convenience as well as
; some common settings and their meanings.
; By default, PHP is set to take action on all errors, notices and warnings EXCEPT
; those related to E_NOTICE and E_STRICT, which together cover best practices and
; recommended coding standards in PHP. For performance reasons, this is the
; recommend error reporting setting. Your production server shouldn't be wasting
; resources complaining about best practices and coding standards. That's what
; development servers and development settings are for.
; Note: The php.ini-development file has this setting as E_ALL. This
; means it pretty much reports everything which is exactly what you want during
; development and early testing.
;
; Error Level Constants:
; E_ALL             - All errors and warnings (includes E_STRICT as of PHP 5.4.0)
; E_ERROR           - fatal run-time errors
; E_RECOVERABLE_ERROR  - almost fatal run-time errors
; E_WARNING         - run-time warnings (non-fatal errors)
; E_PARSE           - compile-time parse errors
; E_NOTICE          - run-time notices (these are warnings which often result
;                     from a bug in your code, but it's possible that it was
;                     intentional (e.g., using an uninitialized variable and
;                     relying on the fact it is automatically initialized to an
;                     empty string)
; E_STRICT          - run-time notices, enable to have PHP suggest changes
;                     to your code which will ensure the best interoperability
;                     and forward compatibility of your code
; E_CORE_ERROR      - fatal errors that occur during PHP's initial startup
; E_CORE_WARNING    - warnings (non-fatal errors) that occur during PHP's
;                     initial startup
; E_COMPILE_ERROR   - fatal compile-time errors
; E_COMPILE_WARNING - compile-time warnings (non-fatal errors)
; E_USER_ERROR      - user-generated error message
; E_USER_WARNING    - user-generated warning message
; E_USER_NOTICE     - user-generated notice message
; E_DEPRECATED      - warn about code that will not work in future versions
;                     of PHP
; E_USER_DEPRECATED - user-generated deprecation warnings
;
; Common Values:
;   E_ALL (Show all errors, warnings and notices including coding standards.)
;   E_ALL & ~E_NOTICE  (Show all errors, except for notices)
;   E_ALL & ~E_NOTICE & ~E_STRICT  (Show all errors, except for notices and coding standards warnings.)
;   E_COMPILE_ERROR|E_RECOVERABLE_ERROR|E_ERROR|E_CORE_ERROR  (Show only errors)
; Default Value: E_ALL & ~E_NOTICE & ~E_STRICT & ~E_DEPRECATED
; Development Value: E_ALL
; Production Value: E_ALL & ~E_DEPRECATED & ~E_STRICT
; http://php.net/error-reporting
error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT

For pure development I go for:

error_reporting = E_ALL ^ E_NOTICE ^ E_WARNING

Also don't forget to put display_errors to on

display_errors = On

After that, restart your server for Apache on Ubuntu:

sudo /etc/init.d/apache2 restart

How to get controls in WPF to fill available space?

Well, I figured it out myself, right after posting, which is the most embarassing way. :)

It seems every member of a StackPanel will simply fill its minimum requested size.

In the DockPanel, I had docked things in the wrong order. If the TextBox or ListBox is the only docked item without an alignment, or if they are the last added, they WILL fill the remaining space as wanted.

I would love to see a more elegant method of handling this, but it will do.

$ is not a function - jQuery error

In my case I was using jquery on my typescript file:

import * as $ from "jquery";

But this line gives me back an Object $ and it does not allow to use as a function (I can not use $('my-selector')). It solves my problem this lines, I hope it could help anyone else:

import * as JQuery from "jquery";
const $ = JQuery.default;

How to detect DataGridView CheckBox event change?

Removing the focus after the cell value changes allow the values to update in the DataGridView. Remove the focus by setting the CurrentCell to null.

private void DataGridView1OnCellValueChanged(object sender, DataGridViewCellEventArgs dataGridViewCellEventArgs)
{
    // Remove focus
    dataGridView1.CurrentCell = null;
    // Put in updates
    Update();
}

private void DataGridView1OnCurrentCellDirtyStateChanged(object sender, EventArgs eventArgs)
{
    if (dataGridView1.IsCurrentCellDirty)
    {
        dataGridView1.CommitEdit(DataGridViewDataErrorContexts.Commit);
    }

}

ASP.NET file download from server

Try this set of code to download a CSV file from the server.

byte[] Content= File.ReadAllBytes(FilePath); //missing ;
Response.ContentType = "text/csv";
Response.AddHeader("content-disposition", "attachment; filename=" + fileName + ".csv");
Response.BufferOutput = true;
Response.OutputStream.Write(Content, 0, Content.Length);
Response.End();

MySQL LEFT JOIN Multiple Conditions

Correct answer is simply:

SELECT a.group_id
FROM a 
LEFT JOIN b ON a.group_id=b.group_id  and b.user_id = 4
where b.user_id is null
  and a.keyword like '%keyword%'

Here we are checking user_id = 4 (your user id from the session). Since we have it in the join criteria, it will return null values for any row in table b that does not match the criteria - ie, any group that that user_id is NOT in.

From there, all we need to do is filter for the null values, and we have all the groups that your user is not in.

demo here

How to change the Content of a <textarea> with JavaScript

If it's jQuery...

$("#myText").val('');

or

document.getElementById('myText').value = '';

Reference: Text Area Object

Box shadow in IE7 and IE8

You could try this

box-shadow:
progid:DXImageTransform.Microsoft.dropshadow(OffX=0, OffY=10, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=10, OffY=20, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=20, OffY=30, Color='#19000000'), 
progid:DXImageTransform.Microsoft.dropshadow(OffX=30, OffY=40, Color='#19000000');

JUnit Testing Exceptions

are you sure you told it to expect the exception?

for newer junit (>= 4.7), you can use something like (from here)

@Rule
public ExpectedException exception = ExpectedException.none();

@Test
public void testRodneCisloRok(){
    exception.expect(IllegalArgumentException.class);
    exception.expectMessage("error1");
    new RodneCislo("891415",dopocitej("891415"));
}

and for older junit, this:

@Test(expected = ArithmeticException.class)  
public void divisionWithException() {  
  int i = 1/0;
}

Cannot convert lambda expression to type 'string' because it is not a delegate type

For people just stumbling upon this now, I resolved an error of this type that was thrown with all the references and using statements placed properly. There's evidently some confusion with substituting in a function that returns DataTable instead of calling it on a declared DataTable. For example:

This worked for me:

DataTable dt = SomeObject.ReturnsDataTable();

List<string> ls = dt.AsEnumerable().Select(dr => dr["name"].ToString()).ToList<string>();

But this didn't:

List<string> ls = SomeObject.ReturnsDataTable().AsEnumerable().Select(dr => dr["name"].ToString()).ToList<string>();

I'm still not 100% sure why, but if anyone is frustrated by an error of this type, give this a try.

What is the difference between SQL, PL-SQL and T-SQL?

SQL

SQL is used to communicate with a database, it is the standard language for relational database management systems.

In detail Structured Query Language is a special-purpose programming language designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS).

Originally based upon relational algebra and tuple relational calculus, SQL consists of a data definition language and a data manipulation language. The scope of SQL includes data insert, query, update and delete, schema creation and modification, and data access control. Although SQL is often described as, and to a great extent is, a declarative language (4GL), it also includes procedural elements.

PL/SQL

PL/SQL is a combination of SQL along with the procedural features of programming languages. It was developed by Oracle Corporation

Specialities of PL/SQL

  • completely portable, high-performance transaction-processing language.
  • provides a built-in interpreted and OS independent programming environment.
  • directly be called from the command-line SQL*Plus interface.
  • Direct call can also be made from external programming language calls to database.
  • general syntax is based on that of ADA and Pascal programming language.
  • Apart from Oracle, it is available in TimesTen in-memory database and IBM DB2.

T-SQL

Short for Transaction-SQL, an extended form of SQL that adds declared variables, transaction control, error and exceptionhandling and row processing to SQL

The Structured Query Language or SQL is a programming language that focuses on managing relational databases. SQL has its own limitations which spurred the software giant Microsoft to build on top of SQL with their own extensions to enhance the functionality of SQL. Microsoft added code to SQL and called it Transact-SQL or T-SQL. Keep in mind that T-SQL is proprietary and is under the control of Microsoft while SQL, although developed by IBM, is already an open format.

T-SQL adds a number of features that are not available in SQL.

This includes procedural programming elements and a local variable to provide more flexible control of how the application flows. A number of functions were also added to T-SQL to make it more powerful; functions for mathematical operations, string operations, date and time processing, and the like. These additions make T-SQL comply with the Turing completeness test, a test that determines the universality of a computing language. SQL is not Turing complete and is very limited in the scope of what it can do.

Another significant difference between T-SQL and SQL is the changes done to the DELETE and UPDATE commands that are already available in SQL. With T-SQL, the DELETE and UPDATE commands both allow the inclusion of a FROM clause which allows the use of JOINs. This simplifies the filtering of records to easily pick out the entries that match a certain criteria unlike with SQL where it can be a bit more complicated.

Choosing between T-SQL and SQL is all up to the user. Still, using T-SQL is still better when you are dealing with Microsoft SQL Server installations. This is because T-SQL is also from Microsoft, and using the two together maximizes compatibility. SQL is preferred by people who have multiple backends.

References , Wikipedea , Tutorial Points :www.differencebetween.com

Understanding generators in Python

Experience with list comprehensions has shown their widespread utility throughout Python. However, many of the use cases do not need to have a full list created in memory. Instead, they only need to iterate over the elements one at a time.

For instance, the following summation code will build a full list of squares in memory, iterate over those values, and, when the reference is no longer needed, delete the list:

sum([x*x for x in range(10)])

Memory is conserved by using a generator expression instead:

sum(x*x for x in range(10))

Similar benefits are conferred on constructors for container objects:

s = Set(word  for line in page  for word in line.split())
d = dict( (k, func(k)) for k in keylist)

Generator expressions are especially useful with functions like sum(), min(), and max() that reduce an iterable input to a single value:

max(len(line)  for line in file  if line.strip())

more

How to use the 'main' parameter in package.json?

From the npm documentation:

The main field is a module ID that is the primary entry point to your program. That is, if your package is named foo, and a user installs it, and then does require("foo"), then your main module's exports object will be returned.

This should be a module ID relative to the root of your package folder.

For most modules, it makes the most sense to have a main script and often not much else.

To put it short:

  1. You only need a main parameter in your package.json if the entry point to your package differs from index.js in its root folder. For example, people often put the entry point to lib/index.js or lib/<packagename>.js, in this case the corresponding script must be described as main in package.json.
  2. You can't have two scripts as main, simply because the entry point require('yourpackagename') must be defined unambiguously.

Print "\n" or newline characters as part of the output on terminal

Use repr

>>> string = "abcd\n"
>>> print(repr(string))
'abcd\n'

How add spaces between Slick carousel item

The slick-slide has inner wrapping div which you can use to create spacing between slides without breaking the design:

.slick-list {margin: 0 -5px;}
.slick-slide>div {padding: 0 5px;}

Detecting request type in PHP (GET, POST, PUT or DELETE)

REST in PHP can be done pretty simple. Create http://example.com/test.php (outlined below). Use this for REST calls, e.g. http://example.com/test.php/testing/123/hello. This works with Apache and Lighttpd out of the box, and no rewrite rules are needed.

<?php
$method = $_SERVER['REQUEST_METHOD'];
$request = explode("/", substr(@$_SERVER['PATH_INFO'], 1));

switch ($method) {
  case 'PUT':
    do_something_with_put($request);  
    break;
  case 'POST':
    do_something_with_post($request);  
    break;
  case 'GET':
    do_something_with_get($request);  
    break;
  default:
    handle_error($request);  
    break;
}

Convert number of minutes into hours & minutes using PHP

check this link for better solution. Click here

How to convert hh:mm:ss to minutes

$minutes=$item['time_diff'];
$hours =   sprintf('%02d',intdiv($minutes, 60)) .':'. ( sprintf('%02d',$minutes % 60));

git checkout master error: the following untracked working tree files would be overwritten by checkout

do a :

git branch

if git show you something like :

* (no branch)
master
Dbranch

You have a "detached HEAD". If you have modify some files on this branch you, commit them, then return to master with

git checkout master 

Now you should be able to delete the Dbranch.

Oracle's default date format is YYYY-MM-DD, WHY?

It's never wise to rely on defaults being set to a particular value, IMHO, whether it's for date formats, currency formats, optimiser modes or whatever. You should always set the value of date format that you need, in the server, the client, or the application.

In particular, never rely on defaults when converting date or numeric data types for display purposes, because a single change to the database can break your application. Always use an explicit conversion format. For years I worked on Oracle systems where the out of the box default date display format was MM/DD/RR, which drove me nuts but at least forced me to always use an explicit conversion.

paint() and repaint() in Java

The paint() method supports painting via a Graphics object.

The repaint() method is used to cause paint() to be invoked by the AWT painting thread.

C# - Substring: index and length must refer to a location within the string

You need to find the position of the first /, and then calculate the portion you want:

string url = "www.example.com/aaa/bbb.jpg";
int Idx = url.IndexOf("/");
string yourValue = url.Substring(Idx + 1, url.Length - Idx - 4);

Importing large sql file to MySql via command line

The solution I use for large sql restore is a mysqldumpsplitter script. I split my sql.gz into individual tables. then load up something like mysql workbench and process it as a restore to the desired schema.

Here is the script https://github.com/kedarvj/mysqldumpsplitter

And this works for larger sql restores, my average on one site I work with is a 2.5gb sql.gz file, 20GB uncompressed, and ~100Gb once restored fully

No ConcurrentList<T> in .Net 4.0?

The reason why there is no ConcurrentList is because it fundamentally cannot be written. The reason why is that several important operations in IList rely on indices, and that just plain won't work. For example:

int catIndex = list.IndexOf("cat");
list.Insert(catIndex, "dog");

The effect that the author is going after is to insert "dog" before "cat", but in a multithreaded environment, anything can happen to the list between those two lines of code. For example, another thread might do list.RemoveAt(0), shifting the entire list to the left, but crucially, catIndex will not change. The impact here is that the Insert operation will actually put the "dog" after the cat, not before it.

The several implementations that you see offered as "answers" to this question are well-meaning, but as the above shows, they don't offer reliable results. If you really want list-like semantics in a multithreaded environment, you can't get there by putting locks inside the list implementation methods. You have to ensure that any index you use lives entirely inside the context of the lock. The upshot is that you can use a List in a multithreaded environment with the right locking, but the list itself cannot be made to exist in that world.

If you think you need a concurrent list, there are really just two possibilities:

  1. What you really need is a ConcurrentBag
  2. You need to create your own collection, perhaps implemented with a List and your own concurrency control.

If you have a ConcurrentBag and are in a position where you need to pass it as an IList, then you have a problem, because the method you're calling has specified that they might try to do something like I did above with the cat & dog. In most worlds, what that means is that the method you're calling is simply not built to work in a multi-threaded environment. That means you either refactor it so that it is or, if you can't, you're going to have to handle it very carefully. You you'll almost certainly be required to create your own collection with its own locks, and call the offending method within a lock.

Basic HTTP and Bearer Token Authentication

curl --anyauth

Tells curl to figure out authentication method by itself, and use the most secure one the remote site claims to support. This is done by first doing a request and checking the response- headers, thus possibly inducing an extra network round-trip. This is used instead of setting a specific authentication method, which you can do with --basic, --digest, --ntlm, and --negotiate.

Create a list with initial capacity in Python

For some applications, a dictionary may be what you are looking for. For example, in the find_totient method, I found it more convenient to use a dictionary since I didn't have a zero index.

def totient(n):
    totient = 0

    if n == 1:
        totient = 1
    else:
        for i in range(1, n):
            if math.gcd(i, n) == 1:
                totient += 1
    return totient

def find_totients(max):
    totients = dict()
    for i in range(1,max+1):
        totients[i] = totient(i)

    print('Totients:')
    for i in range(1,max+1):
        print(i,totients[i])

This problem could also be solved with a preallocated list:

def find_totients(max):
    totients = None*(max+1)
    for i in range(1,max+1):
        totients[i] = totient(i)

    print('Totients:')
    for i in range(1,max+1):
        print(i,totients[i])

I feel that this is not as elegant and prone to bugs because I'm storing None which could throw an exception if I accidentally use them wrong, and because I need to think about edge cases that the map lets me avoid.

It's true the dictionary won't be as efficient, but as others have commented, small differences in speed are not always worth significant maintenance hazards.

perform an action on checkbox checked or unchecked event on html form

The problem is how you've attached the listener:

<input type="checkbox" ...  onchange="doalert(this.id)">

Inline listeners are effectively wrapped in a function which is called with the element as this. That function then calls the doalert function, but doesn't set its this so it will default to the global object (window in a browser).

Since the window object doesn't have a checked property, this.checked always resolves to false.

If you want this within doalert to be the element, attach the listener using addEventListener:

window.onload = function() {
  var input = document.querySelector('#g01-01');
  if (input) {   
    input.addEventListener('change', doalert, false);
  }
}

Or if you wish to use an inline listener:

<input type="checkbox" ...  onchange="doalert.call(this, this.id)">

How To fix white screen on app Start up?

Make a style in you style.xml as follows :

<style name="Theme.Transparent" parent="Theme.AppCompat.Light.NoActionBar">
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowActionBar">false</item>
    <item name="android:windowFullscreen">true</item>
    <item name="android:windowContentOverlay">@null</item>
    <item name="android:windowIsTranslucent">true</item>
</style>

and use it with your activity in AndroidManifest as:

<activity android:name=".ActivitySplash" android:theme="@style/Theme.Transparent">

How should we manage jdk8 stream for null values

Current thinking seems to be to "tolerate" nulls, that is, to allow them in general, although some operations are less tolerant and may end up throwing NPE. See the discussion of nulls on the Lambda Libraries expert group mailing list, specifically this message. Consensus around option #3 subsequently emerged (with a notable objection from Doug Lea). So yes, the OP's concern about pipelines blowing up with NPE is valid.

It's not for nothing that Tony Hoare referred to nulls as the "Billion Dollar Mistake." Dealing with nulls is a real pain. Even with classic collections (without considering lambdas or streams) nulls are problematic. As fge mentioned in a comment, some collections allow nulls and others do not. With collections that allow nulls, this introduces ambiguities into the API. For example, with Map.get(), a null return indicates either that the key is present and its value is null, or that the key is absent. One has to do extra work to disambiguate these cases.

The usual use for null is to denote the absence of a value. The approach for dealing with this proposed for Java SE 8 is to introduce a new java.util.Optional type, which encapsulates the presence/absence of a value, along with behaviors of supplying a default value, or throwing an exception, or calling a function, etc. if the value is absent. Optional is used only by new APIs, though, everything else in the system still has to put up with the possibility of nulls.

My advice is to avoid actual null references to the greatest extent possible. It's hard to see from the example given how there could be a "null" Otter. But if one were necessary, the OP's suggestions of filtering out null values, or mapping them to a sentinel object (the Null Object Pattern) are fine approaches.

ERROR: SQLSTATE[HY000] [2002] No connection could be made because the target machine actively refused it

You should restart your Xampp or whatever server you're runnung, make sure sq

Setting up SSL on a local xampp/apache server

I did most of the suggested stuff here, still didnt work. Tried this and it worked: Open your XAMPP Control Panel, locate the Config button for the Apache module. Click on the Config button and Select PHP (php.ini). Open with any text editor and remove the semi-column before php_openssl. Save and Restart Apache. That should do!

How to downgrade tensorflow, multiple versions possible?

Click to green checkbox on installed tensorflow and choose needed versionscreenshot Anaconda navigator