SyntaxFix

Programs & Examples On #Querying

Nested select statement in SQL Server

You need to alias the subquery.

SELECT name FROM (SELECT name FROM agentinformation) a

or to be more explicit

SELECT a.name FROM (SELECT name FROM agentinformation) a

Is there a query language for JSON?

  1. Google has a project called lovefield; just found out about it, and it looks interesting, though it is more involved than just dropping in underscore or lodash.

    https://github.com/google/lovefield

Lovefield is a relational query engine written in pure JavaScript. It also provides help with persisting data on the browser side, e.g. using IndexedDB to store data locally. It provides SQL-like syntax and works cross-browser (currently supporting Chrome 37+, Firefox 31+, IE 10+, and Safari 5.1+...

  1. Another interesting recent entry in this space called jinqJs.

    http://www.jinqjs.com/

    Briefly reviewing the examples, it looks promising, and the API document appears to be well written.

function isChild(row) {
  return (row.Age < 18 ? 'Yes' : 'No');
}

var people = [
  {Name: 'Jane', Age: 20, Location: 'Smithtown'},
  {Name: 'Ken', Age: 57, Location: 'Islip'},
  {Name: 'Tom', Age: 10, Location: 'Islip'}
];

var result = new jinqJs()
  .from(people)
  .orderBy('Age')
  .select([{field: 'Name'}, 
     {field: 'Age', text: 'Your Age'}, 
     {text: 'Is Child', value: isChild}]);

jinqJs is a small, simple, lightweight and extensible javaScript library that has no dependencies. jinqJs provides a simple way to perform SQL like queries on javaScript arrays, collections and web services that return a JSON response. jinqJs is similar to Microsoft's Lambda expression for .Net, and it provides similar capabilities to query collections using a SQL like syntax and predicate functionality. jinqJs’s purpose is to provide a SQL like experience to programmers familiar with LINQ queries.

How to customize <input type="file">?

If you're using bootstrap here is a better solution :

<label class="btn btn-default btn-file">
    Browse <input type="file" style="display: none;" required>
</label>

For IE8 and below http://www.abeautifulsite.net/whipping-file-inputs-into-shape-with-bootstrap-3/

Source : https://stackoverflow.com/a/18164555/625952

Hide scroll bar, but while still being able to scroll

As of December 11th 2018 (Firefox 64 and above), the answer to this question is very simple indeed as Firefox 64+ now implements the CSS Scrollbar Styling spec.

Just use the following CSS:

scrollbar-width: none;

Firefox 64 release note link here.

How do I apply a CSS class to Html.ActionLink in ASP.NET MVC?

@ewomack has a great answer for C#, unless you don't need extra object values. In my case, I ended up using something similar to:

@Html.ActionLink("Delete", "DeleteList", "List", new object { },
new { @class = "delete"})

Bootstrap 3.0 Sliding Menu from left

Probably late but here is a plugin that can do the job : http://multi-level-push-menu.make.rs/

Also v2 can use mobile gesture such as swipe ;)

Default visibility for C# classes and members (fields, methods, etc.)?

From MSDN:

Top-level types, which are not nested in other types, can only have internal or public accessibility. The default accessibility for these types is internal.

Nested types, which are members of other types, can have declared accessibilities as indicated in the following table.

Default Nested Member Accessibility & Allowed Accessibility Modifiers

Source: Accessibility Levels (C# Reference) (December 6th, 2017)

Change HTML email body font type and size in VBA

I did a little research and was able to write this code:

strbody = "<BODY style=font-size:11pt;font-family:Calibri>Good Morning;<p>We have completed our main aliasing process for today.  All assigned firms are complete.  Please feel free to respond with any questions.<p>Thank you.</BODY>"

apparently by setting the "font-size=11pt" instead of setting the font size <font size=5>, It allows you to select a specific font size like you normally would in a text editor, as opposed to selecting a value from 1-7 like my code was originally.

This link from simpLE MAn gave me some good info.

Button background as transparent

Code:

button.setVisibility(View.INVISIBLE);

Xml:

android:background="@android:color/transparent"

Why is there no Char.Empty like String.Empty?

Use Char.MinValue which works the same as '\0'. But be careful it is not the same as String.Empty.

Moment.js with Vuejs

vue-moment

very nice plugin for vue project and works very smoothly with the components and existing code. Enjoy the moments...

// in your main.js
Vue.use(require('vue-moment'));
// and use in component
{{'2019-10-03 14:02:22' | moment("calendar")}}
// or like this
{{created_at | moment("calendar")}}

Foreign Key to non-primary key

As others have pointed out, ideally, the foreign key would be created as a reference to a primary key (usually an IDENTITY column). However, we don't live in an ideal world, and sometimes even a "small" change to a schema can have significant ripple effects to the application logic.

Consider the case of a Customer table with a SSN column (and a dumb primary key), and a Claim table that also contains a SSN column (populated by business logic from the Customer data, but no FK exists). The design is flawed, but has been in use for several years, and three different applications have been built on the schema. It should be obvious that ripping out Claim.SSN and putting in a real PK-FK relationship would be ideal, but would also be a significant overhaul. On the other hand, putting a UNIQUE constraint on Customer.SSN, and adding a FK on Claim.SSN, could provide referential integrity, with little or no impact on the applications.

Don't get me wrong, I'm all for normalization, but sometimes pragmatism wins over idealism. If a mediocre design can be helped with a band-aid, surgery might be avoided.

HTTP response code for POST when resource already exists

Another potential treatment is using PATCH after all. A PATCH is defined as something that changes the internal state and is not restricted to appending.

PATCH would solve the problem by allowing you to update already existing items. See: RFC 5789: PATCH

Datetime BETWEEN statement not working in SQL Server

You don't have any error in either of your queries. My guess is the following:

  • No records exists between 2013-10-17' and '2013-10-18'
  • the records the second query returns you exist after '2013-10-18'

jQuery jump or scroll to certain position, div or target on the page from button onclick

I would style a link to look like a button, because that way there is a no-js fallback.

So this is how you could animate the jump using jquery. No-js fallback is a normal jump without animation.

Original example:

jsfiddle

_x000D_
_x000D_ 
$(document).ready(function() {_x000D_
  $(".jumper").on("click", function( e ) {_x000D_
_x000D_
    e.preventDefault();_x000D_
_x000D_
    $("body, html").animate({ _x000D_
      scrollTop: $( $(this).attr('href') ).offset().top _x000D_
    }, 600);_x000D_
_x000D_
  });_x000D_
});
_x000D_ 
#long {_x000D_
  height: 500px;_x000D_
  background-color: blue;_x000D_
}
_x000D_ 
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<!-- Links that trigger the jumping -->_x000D_
<a class="jumper" href="#pliip">Pliip</a>_x000D_
<a class="jumper" href="#ploop">Ploop</a>_x000D_
<div id="long">...</div>_x000D_
<!-- Landing elements -->_x000D_
<div id="pliip">pliip</div>_x000D_
<div id="ploop">ploop</div>
_x000D_
_x000D_
_x000D_

New example with actual button styles for the links, just to prove a point.

Everything is essentially the same, except that I changed the class .jumper to .button and I added css styling to make the links look like buttons.

Button styles example

how to get javaScript event source element?

I believe the solution by @slipset was correct, but wasn't cross-browser ready.

According to Javascript.info, events (when referenced outside markup events) are cross-browser ready once you assure it's defined with this simple line: event = event || window.event.

So the complete cross-browser ready function would look like this:

function doSomething(param){
  event = event || window.event;
  var source = event.target || event.srcElement;
  console.log(source);
}

How to encrypt a large file in openssl using public key

I found the instructions at http://www.czeskis.com/random/openssl-encrypt-file.html useful.

To paraphrase the linked site with filenames from your example:

Generate a symmetric key because you can encrypt large files with it

openssl rand -base64 32 > key.bin

Encrypt the large file using the symmetric key

openssl enc -aes-256-cbc -salt -in myLargeFile.xml \
  -out myLargeFile.xml.enc -pass file:./key.bin

Encrypt the symmetric key so you can safely send it to the other person

openssl rsautl -encrypt -inkey public.pem -pubin -in key.bin -out key.bin.enc

Destroy the un-encrypted symmetric key so nobody finds it

shred -u key.bin

At this point, you send the encrypted symmetric key (key.bin.enc) and the encrypted large file (myLargeFile.xml.enc) to the other person

The other person can then decrypt the symmetric key with their private key using

openssl rsautl -decrypt -inkey private.pem -in key.bin.enc -out key.bin

Now they can use the symmetric key to decrypt the file

openssl enc -d -aes-256-cbc -in myLargeFile.xml.enc \
  -out myLargeFile.xml -pass file:./key.bin

And you're done. The other person has the decrypted file and it was safely sent.

How to get started with Windows 7 gadgets

Here's an excellent article by Scott Allen: Developing Gadgets for the Windows Sidebar

This site, Windows 7/Vista Sidebar Gadgets, has links to many gadget resources.

Laravel redirect back to original destination after login

 
return Redirect::intended('/');

this will redirect you to default page of your project i.e. start page.

How to replicate background-attachment fixed on iOS

It has been asked in the past, apparently it costs a lot to mobile browsers, so it's been disabled.

Check this comment by @PaulIrish:

Fixed-backgrounds have huge repaint cost and decimate scrolling performance, which is, I believe, why it was disabled.

you can see workarounds to this in this posts:

Fixed background image with ios7

Fixed body background scrolls with the page on iOS7

Getting a POST variable

Use this for GET values:

Request.QueryString["key"]

And this for POST values

Request.Form["key"]

Also, this will work if you don't care whether it comes from GET or POST, or the HttpContext.Items collection:

Request["key"]

Another thing to note (if you need it) is you can check the type of request by using:

Request.RequestType

Which will be the verb used to access the page (usually GET or POST). Request.IsPostBack will usually work to check this, but only if the POST request includes the hidden fields added to the page by the ASP.NET framework.

Javascript : natural sort of alphanumerical strings

Building on @Adrien Be's answer above and using the code that Brian Huisman & David koelle created, here is a modified prototype sorting for an array of objects:

//Usage: unsortedArrayOfObjects.alphaNumObjectSort("name");
//Test Case: var unsortedArrayOfObjects = [{name: "a1"}, {name: "a2"}, {name: "a3"}, {name: "a10"}, {name: "a5"}, {name: "a13"}, {name: "a20"}, {name: "a8"}, {name: "8b7uaf5q11"}];
//Sorted: [{name: "8b7uaf5q11"}, {name: "a1"}, {name: "a2"}, {name: "a3"}, {name: "a5"}, {name: "a8"}, {name: "a10"}, {name: "a13"}, {name: "a20"}]

// **Sorts in place**
Array.prototype.alphaNumObjectSort = function(attribute, caseInsensitive) {
  for (var z = 0, t; t = this[z]; z++) {
    this[z].sortArray = new Array();
    var x = 0, y = -1, n = 0, i, j;

    while (i = (j = t[attribute].charAt(x++)).charCodeAt(0)) {
      var m = (i == 46 || (i >=48 && i <= 57));
      if (m !== n) {
        this[z].sortArray[++y] = "";
        n = m;
      }
      this[z].sortArray[y] += j;
    }
  }

  this.sort(function(a, b) {
    for (var x = 0, aa, bb; (aa = a.sortArray[x]) && (bb = b.sortArray[x]); x++) {
      if (caseInsensitive) {
        aa = aa.toLowerCase();
        bb = bb.toLowerCase();
      }
      if (aa !== bb) {
        var c = Number(aa), d = Number(bb);
        if (c == aa && d == bb) {
          return c - d;
        } else {
          return (aa > bb) ? 1 : -1;
        }
      }
    }

    return a.sortArray.length - b.sortArray.length;
  });

  for (var z = 0; z < this.length; z++) {
    // Here we're deleting the unused "sortArray" instead of joining the string parts
    delete this[z]["sortArray"];
  }
}

Embed HTML5 YouTube video without iframe?

Yes, but it depends on what you mean by 'embed'; as far as I can tell after reading through the docs, it seems like you have a couple of options if you want to get around using the iframe API. You can use the javascript and flash API's (https://developers.google.com/youtube/player_parameters) to embed a player, but that involves creating Flash objects in your code (something I personally avoid, but not necessarily something that you have to). Below are some helpful sections from the dev docs for the Youtube API.

If you really want to get around all these methods and include video without any sort of iframe, then your best bet might be creating an HTML5 video player/app that can connect to the Youtube Data API (https://developers.google.com/youtube/v3/). I'm not sure what the extent of your needs are, but this would be the way to go if you really want to get around using any iframes or flash objects.

Hope this helps!

Useful:

(https://developers.google.com/youtube/player_parameters)

IFrame embeds using the IFrame Player API

Follow the IFrame Player API instructions to insert a video player in your web page or application after the Player API's JavaScript code has loaded. The second parameter in the constructor for the video player is an object that specifies player options. Within that object, the playerVars property identifies player parameters.

The HTML and JavaScript code below shows a simple example that inserts a YouTube player into the page element that has an id value of ytplayer. The onYouTubePlayerAPIReady() function specified here is called automatically when the IFrame Player API code has loaded. This code does not define any player parameters and also does not define other event handlers.

...

IFrame embeds using tags

Define an tag in your application in which the src URL specifies the content that the player will load as well as any other player parameters you want to set. The tag's height and width parameters specify the dimensions of the player.

If you are creating the element yourself (rather than using the IFrame Player API to create it), you can append player parameters directly to the end of the URL. The URL has the following format:

...

AS3 object embeds

Object embeds use an tag to specify the player's dimensions and parameters. The sample code below demonstrates how to use an object embed to load an AS3 player that automatically plays the same video as the previous two examples.

How should I cast in VB.NET?

MSDN seems to indicate that the Cxxx casts for specific types can improve performance in VB .NET because they are converted to inline code. For some reason, it also suggests DirectCast as opposed to CType in certain cases (the documentations states it's when there's an inheritance relationship; I believe this means the sanity of the cast is checked at compile time and optimizations can be applied whereas CType always uses the VB runtime.)

When I'm writing VB .NET code, what I use depends on what I'm doing. If it's prototype code I'm going to throw away, I use whatever I happen to type. If it's code I'm serious about, I try to use a Cxxx cast. If one doesn't exist, I use DirectCast if I have a reasonable belief that there's an inheritance relationship. If it's a situation where I have no idea if the cast should succeed (user input -> integers, for example), then I use TryCast so as to do something more friendly than toss an exception at the user.

One thing I can't shake is I tend to use ToString instead of CStr but supposedly Cstr is faster.

JavaScript for...in vs for

Douglas Crockford recommends in JavaScript: The Good Parts (page 24) to avoid using the for in statement.

If you use for in to loop over property names in an object, the results are not ordered. Worse: You might get unexpected results; it includes members inherited from the prototype chain and the name of methods.

Everything but the properties can be filtered out with .hasOwnProperty. This code sample does what you probably wanted originally:

for (var name in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, name)) {
        // DO STUFF
    }
}

Add leading zeroes/0's to existing Excel values to certain length

If you use custom formatting and need to concatenate those values elsewhere, you can copy them and Paste Special --> Values elsewhere in the sheet (or on a different sheet), then concatenate those values.

Remove Object from Array using JavaScript

This is what I use.

Array.prototype.delete = function(pos){
    this[pos] = undefined;
    var len = this.length - 1;
    for(var a = pos;a < this.length - 1;a++){
      this[a] = this[a+1];
    }
    this.pop();
  }

Then it is as simple as saying

var myArray = [1,2,3,4,5,6,7,8,9];
myArray.delete(3);

Replace any number in place of three. After the expected output should be:

console.log(myArray); //Expected output 1,2,3,5,6,7,8,9

FragmentActivity to Fragment

first of all;

a Fragment must be inside a FragmentActivity, that's the first rule,

a FragmentActivity is quite similar to a standart Activity that you already know, besides having some Fragment oriented methods

second thing about Fragments, is that there is one important method you MUST call, wich is onCreateView, where you inflate your layout, think of it as the setContentLayout

here is an example:

    @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {     mView       = inflater.inflate(R.layout.fragment_layout, container, false);       return mView; }

and continu your work based on that mView, so to find a View by id, call mView.findViewById(..);

for the FragmentActivity part:

the xml part "must" have a FrameLayout in order to inflate a fragment in it

        <FrameLayout             android:id="@+id/content_frame"             android:layout_width="match_parent"             android:layout_height="match_parent"  >         </FrameLayout>

as for the inflation part

getSupportFragmentManager().beginTransaction().replace(R.id.content_frame, new YOUR_FRAGMENT, "TAG").commit();

begin with these, as there is tons of other stuf you must know about fragments and fragment activities, start of by reading something about it (like life cycle) at the android developer site

Catching an exception while using a Python 'with' statement

 
from __future__ import with_statement

try:
    with open( "a.txt" ) as f :
        print f.readlines()
except EnvironmentError: # parent of IOError, OSError *and* WindowsError where available
    print 'oops'

If you want different handling for errors from the open call vs the working code you could do:

try:
    f = open('foo.txt')
except IOError:
    print('error')
else:
    with f:
        print f.readlines()

Mac OS X and multiple Java versions

I followed steps in below link - https://medium.com/@euedofia/fix-default-java-version-on-maven-on-mac-os-x-156cf5930078 and it worked for me.

cd /usr/local/Cellar/maven/3.5.4/bin/
nano mvn
--Update JAVA_HOME -> "${JAVA_HOME:-$(/usr/libexec/java_home)}"
mvn -version

How to find an available port?

It may not help you much, but on my (Ubuntu) machine I have a file /etc/services in which at least the ports used/reserved by some of the apps are given. These are the standard ports for those apps.

No guarantees that these are running, just the default ports these apps use (so you should not use them if possible).

There are slightly more than 500 ports defined, about half UDP and half TCP.

The files are made using information by IANA, see IANA Assigned port numbers.

Writing List of Strings to Excel CSV File in Python

The csv.writer writerow method takes an iterable as an argument. Your result set has to be a list (rows) of lists (columns).

csvwriter.writerow(row)

Write the row parameter to the writer’s file object, formatted according to the current dialect.

Do either:

import csv
RESULTS = [
    ['apple','cherry','orange','pineapple','strawberry']
]
with open('output.csv','wb') as result_file:
    wr = csv.writer(result_file, dialect='excel')
    wr.writerows(RESULTS)

or:

import csv
RESULT = ['apple','cherry','orange','pineapple','strawberry']
with open('output.csv','wb') as result_file:
    wr = csv.writer(result_file, dialect='excel')
    wr.writerow(RESULT)

How to get text with Selenium WebDriver in Python

You want just .text.

You can then verify it after you've got it, don't attempt to pass in what you expect it should have.

Can I apply a CSS style to an element name?

_x000D_
_x000D_ 
input[type=text] {
  width: 150px;
  length: 150px;
}

input[name=myname] {
  width: 100px;
length: 150px;
}
_x000D_ 
<input type="text">
<br>
<input type="text" name="myname">
_x000D_
_x000D_
_x000D_

Storing a Key Value Array into a compact JSON string

If the logic parsing this knows that {"key": "slide0001.html", "value": "Looking Ahead"} is a key/value pair, then you could transform it in an array and hold a few constants specifying which index maps to which key.

For example:

var data = ["slide0001.html", "Looking Ahead"];

var C_KEY = 0;
var C_VALUE = 1;

var value = data[C_VALUE];

So, now, your data can be:

[
    ["slide0001.html", "Looking Ahead"],
    ["slide0008.html", "Forecast"],
    ["slide0021.html", "Summary"]
]

If your parsing logic doesn't know ahead of time about the structure of the data, you can add some metadata to describe it. For example:

{ meta: { keys: [ "key", "value" ] },
  data: [
    ["slide0001.html", "Looking Ahead"],
    ["slide0008.html", "Forecast"],
    ["slide0021.html", "Summary"]
  ]
}

... which would then be handled by the parser.

AsyncTask Android example

When you are in the worker thread, you can not directly manipulate UI elements on Android.

When you are using AsyncTask please understand the callback methods.

For example:

public class MyAyncTask extends AsyncTask<Void, Void, Void>{

    @Override
    protected void onPreExecute() {
        // Here you can show progress bar or something on the similar lines.
        // Since you are in a UI thread here.
        super.onPreExecute();
    }

    @Override
    protected void onPostExecute(Void aVoid) {
        super.onPostExecute(aVoid);
        // After completing execution of given task, control will return here.
        // Hence if you want to populate UI elements with fetched data, do it here.
    }

    @Override
    protected void onProgressUpdate(Void... values) {
        super.onProgressUpdate(values);
        // You can track you progress update here
    }

    @Override
    protected Void doInBackground(Void... params) {
        // Here you are in the worker thread and you are not allowed to access UI thread from here.
        // Here you can perform network operations or any heavy operations you want.
        return null;
    }
}

FYI: To access the UI thread from a worker thread, you either use runOnUiThread() method or post method on your view.

For instance:

runOnUiThread(new Runnable() {
    textView.setText("something.");
});

or
    yourview.post(new Runnable() {
    yourview.setText("something");
});

This will help you know the things better. Hence in you case, you need to set your textview in the onPostExecute() method.

How do I setup the dotenv file in Node.js?

My code structure using is as shown below

-.env
-app.js
-build
-src
   |-modules
        |-users
            |-controller
                  |-userController.js

I have required .env at the top of my app.js

require('dotenv').config();
import express = require('express');
import bodyParser from 'body-parser';
import mongoose = require('mongoose');

The process.env.PORT works in my app.listen function. However, on my userController file not sure how this is happening but my problem was I was getting the secretKey value and type as string when I checked using console.log() but getting undefined when trying it on jwt.sign() e.g.

console.log('Type: '+ process.env.ACCESS_TOKEN_SECRET)
console.log(process.env.ACCESS_TOKEN_SECRET)

Result:

string
secret

jwt.sign giving error

let accessToken = jwt.sign(userObj, process.env.ACCESS_TOKEN_SECRET); //not working

Error was

    Argument of type 'string | undefined' is not assignable to parameter of type 'Secret'.
  Type 'undefined' is not assignable to type 'Secret'.

My Solution: After reading the documentation. I required the env again in my file( which I probably should have in the first place ) and saved it to variable 'environment'

let environment = require('dotenv').config();

console logging environment this gives:

{
parsed: {
    DB_HOST: 'localhost',
    DB_USER: 'root',
    DB_PASS: 'pass',
    PORT: '3000',
    ACCESS_TOKEN_SECRET: 'secretKey',
  }
}

Using it on jwt.sign not works

let accessToken = jwt.sign(userObj, environment.parsed.ACCESS_TOKEN_SECRET);

Hope this helps, I was stuck on it for hours. Please feel free to add anything to my answer which may help explain more on this.

In Bash, how do I add a string after each line in a file?

  1. Pure POSIX shell and sponge:

    suffix=foobar
while read l ; do printf '%s\n' "$l" "${suffix}" ; done < file | 
sponge file

  2. xargs and printf:

    suffix=foobar
xargs -L 1 printf "%s${suffix}\n" < file | sponge file

  3. Using join:

    suffix=foobar
join file file -e "${suffix}" -o 1.1,2.99999 | sponge file

  4. Shell tools using paste, yes, head & wc:

    suffix=foobar
paste file <(yes "${suffix}" | head -$(wc -l < file) ) | sponge file

    Note that paste inserts a Tab char before $suffix.

Of course sponge can be replaced with a temp file, afterwards mv'd over the original filename, as with some other answers...

Operator overloading in Java

As many others have answered: Java doesn't support user-defined operator overloading.

Maybe this is off-topic, but I want to comment on some things I read in some answers.

About readability.
Compare:

  1. c = a + b
  2. c = a.add(b)

Look again!
Which one is more readable?

A programming language that allows the creation of user-defined types, should allow them to act in the same way as the built-in types (or primitive types).

So Java breaks a fundamental principle of Generic Programming:
We should be able to interchange objects of built-in types with objects of user-defined types.
(You may be wondering: "Did he say 'objects of built-in'?". Yes, see here.)

About String concatenation:

Mathematicians use the symbol + for commutative operations on sets.
So we can be sure that a + b = b + a.
String concatenation (in most programming languages) doesn't respect this common mathematical notation.

a := "hello";
b := "world";
c := (a + b = b + a);

or in Java:

String a = "hello";
String b = "world";
boolean c = (a + b).equals(b + a);

Extra:
Notice how in Java equality and identity are confused. The == (equality) symbol means:
a. Equality for primitive types.
b. Identity-check for user-defined types, therefore, we are forced to use the function equals() for equality.
But... What has this to do with operator overloading?
If the language allows the operator overloading the user could give the proper meaning to the equality operator.

How to load a xib file in a UIView

You could try:

UIView *firstViewUIView = [[[NSBundle mainBundle] loadNibNamed:@"firstView" owner:self options:nil] firstObject];
[self.view.containerView addSubview:firstViewUIView];

Equivalent of "continue" in Ruby

Yes, it's called next.

for i in 0..5
   if i < 2
     next
   end
   puts "Value of local variable is #{i}"
end

This outputs the following:

Value of local variable is 2
Value of local variable is 3
Value of local variable is 4
Value of local variable is 5
 => 0..5

How do I show multiple recaptchas on a single page?

A good option is to generate a recaptcha input for each form on the fly (I've done it with two but you could probably do three or more forms). I'm using jQuery, jQuery validation, and jQuery form plugin to post the form via AJAX, along with the Recaptcha AJAX API -

https://developers.google.com/recaptcha/docs/display#recaptcha_methods

When the user submits one of the forms:

  1. intercept the submission - I used jQuery Form Plugin's beforeSubmit property
  2. destroy any existing recaptcha inputs on the page - I used jQuery's $.empty() method and Recaptcha.destroy()
  3. call Recaptcha.create() to create a recaptcha field for the specific form
  4. return false.

Then, they can fill out the recaptcha and re-submit the form. If they decide to submit a different form instead, well, your code checks for existing recaptchas so you'll only have one recaptcha on the page at a time.

IOException: The process cannot access the file 'file path' because it is being used by another process

I got this error because I was doing File.Move to a file path without a file name, need to specify the full path in the destination.

Spring Boot and how to configure connection details to MongoDB?

You can define more details by extending AbstractMongoConfiguration.

@Configuration
@EnableMongoRepositories("demo.mongo.model")
public class SpringMongoConfig extends AbstractMongoConfiguration {
    @Value("${spring.profiles.active}")
    private String profileActive;

    @Value("${spring.application.name}")
    private String proAppName;

    @Value("${spring.data.mongodb.host}")
    private String mongoHost;

    @Value("${spring.data.mongodb.port}")
    private String mongoPort;

    @Value("${spring.data.mongodb.database}")
    private String mongoDB;

    @Override
    public MongoMappingContext mongoMappingContext()
        throws ClassNotFoundException {
        // TODO Auto-generated method stub
        return super.mongoMappingContext();
    }
    @Override
    @Bean
    public Mongo mongo() throws Exception {
        return new MongoClient(mongoHost + ":" + mongoPort);
    }
    @Override
    protected String getDatabaseName() {
        // TODO Auto-generated method stub
        return mongoDB;
    }
}

How can I create a correlation matrix in R?

The cor function will use the columns of the matrix in the calculation of correlation. So, the number of rows must be the same between your matrix x and matrix y. Ex.:

set.seed(1)
x <- matrix(rnorm(20), nrow=5, ncol=4)
y <- matrix(rnorm(15), nrow=5, ncol=3)
COR <- cor(x,y)
COR
image(x=seq(dim(x)[2]), y=seq(dim(y)[2]), z=COR, xlab="x column", ylab="y column")
text(expand.grid(x=seq(dim(x)[2]), y=seq(dim(y)[2])), labels=round(c(COR),2))

enter image description here

Edit:

Here is an example of custom row and column labels on a correlation matrix calculated with a single matrix:

png("corplot.png", width=5, height=5, units="in", res=200)
op <- par(mar=c(6,6,1,1), ps=10)
COR <- cor(iris[,1:4])
image(x=seq(nrow(COR)), y=seq(ncol(COR)), z=cor(iris[,1:4]), axes=F, xlab="", ylab="")
text(expand.grid(x=seq(dim(COR)[1]), y=seq(dim(COR)[2])), labels=round(c(COR),2))
box()
axis(1, at=seq(nrow(COR)), labels = rownames(COR), las=2)
axis(2, at=seq(ncol(COR)), labels = colnames(COR), las=1)
par(op)
dev.off()

enter image description here

Use of contains in Java ArrayList<String>

You are right that it should work; perhaps you forgot to instantiate something. Does your code look something like this?

String rssFeedURL = "http://stackoverflow.com";
this.rssFeedURLS = new ArrayList<String>();
this.rssFeedURLS.add(rssFeedURL);
if(this.rssFeedURLs.contains(rssFeedURL)) {
// this code will execute
}

For reference, note that the following conditional will also execute if you append this code to the above:

String copyURL = new String(rssFeedURL);
if(this.rssFeedURLs.contains(copyURL)) {
// code will still execute because contains() checks equals()
}

Even though (rssFeedURL == copyURL) is false, rssFeedURL.equals(copyURL) is true. The contains method cares about the equals method.

How to import a new font into a project - Angular 5

You can try creating a css for your font with font-face (like explained here)

Step #1

Create a css file with font face and place it somewhere, like in assets/fonts

customfont.css

@font-face {
    font-family: YourFontFamily;
    src: url("/assets/font/yourFont.otf") format("truetype");
}

Step #2

Add the css to your .angular-cli.json in the styles config

"styles":[
 //...your other styles
 "assets/fonts/customFonts.css"
 ]

Do not forget to restart ng serve after doing this

Step #3

Use the font in your code

component.css

span {font-family: YourFontFamily; }

Windows equivalent of OS X Keychain?

It is year 2018, and Windows 10 has a "Credential Manager" that can be found in "Control Panel"

Example: Communication between Activity and Service using Messaging

For sending data to a service you can use:

Intent intent = new Intent(getApplicationContext(), YourService.class);
intent.putExtra("SomeData","ItValue");
startService(intent);

And after in service in onStartCommand() get data from intent.

For sending data or event from a service to an application (for one or more activities):

private void sendBroadcastMessage(String intentFilterName, int arg1, String extraKey) {
    Intent intent = new Intent(intentFilterName);
    if (arg1 != -1 && extraKey != null) {
        intent.putExtra(extraKey, arg1);
    }
    sendBroadcast(intent);
}

This method is calling from your service. You can simply send data for your Activity.

private void someTaskInYourService(){

    //For example you downloading from server 1000 files
    for(int i = 0; i < 1000; i++) {
        Thread.sleep(5000) // 5 seconds. Catch in try-catch block
        sendBroadCastMessage(Events.UPDATE_DOWNLOADING_PROGRESSBAR, i,0,"up_download_progress");
    }

For receiving an event with data, create and register method registerBroadcastReceivers() in your activity:

private void registerBroadcastReceivers(){
    broadcastReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            int arg1 = intent.getIntExtra("up_download_progress",0);
            progressBar.setProgress(arg1);
        }
    };
    IntentFilter progressfilter = new IntentFilter(Events.UPDATE_DOWNLOADING_PROGRESS);
    registerReceiver(broadcastReceiver,progressfilter);

For sending more data, you can modify method sendBroadcastMessage();. Remember: you must register broadcasts in onResume() & unregister in onStop() methods!

UPDATE

Please don't use my type of communication between Activity & Service. This is the wrong way. For a better experience please use special libs, such us:

1) EventBus from greenrobot

2) Otto from Square Inc

P.S. I'm only using EventBus from greenrobot in my projects,

How do I create a custom Error in JavaScript?

Update your code to assign your prototype to the Error.prototype and the instanceof and your asserts work.

function NotImplementedError(message = "") {
    this.name = "NotImplementedError";
    this.message = message;
}
NotImplementedError.prototype = Error.prototype;

However, I would just throw your own object and just check the name property.

throw {name : "NotImplementedError", message : "too lazy to implement"};

Edit based on comments

After looking at the comments and trying to remember why I would assign prototype to Error.prototype instead of new Error() like Nicholas Zakas did in his article, I created a jsFiddle with the code below:

_x000D_
_x000D_ 
function NotImplementedError(message = "") {
  this.name = "NotImplementedError";
  this.message = message;
}
NotImplementedError.prototype = Error.prototype;

function NotImplementedError2(message = "") {
  this.message = message;
}
NotImplementedError2.prototype = new Error();

try {
  var e = new NotImplementedError("NotImplementedError message");
  throw e;
} catch (ex1) {
  console.log(ex1.stack);
  console.log("ex1 instanceof NotImplementedError = " + (ex1 instanceof NotImplementedError));
  console.log("ex1 instanceof Error = " + (ex1 instanceof Error));
  console.log("ex1.name = " + ex1.name);
  console.log("ex1.message = " + ex1.message);
}

try {
  var e = new NotImplementedError2("NotImplementedError2 message");
  throw e;
} catch (ex1) {
  console.log(ex1.stack);
  console.log("ex1 instanceof NotImplementedError2 = " + (ex1 instanceof NotImplementedError2));
  console.log("ex1 instanceof Error = " + (ex1 instanceof Error));
  console.log("ex1.name = " + ex1.name);
  console.log("ex1.message = " + ex1.message);
}
_x000D_
_x000D_
_x000D_

The console output was this.

undefined
ex1 instanceof NotImplementedError = true
ex1 instanceof Error = true
ex1.name = NotImplementedError
ex1.message = NotImplementedError message
Error
    at window.onload (http://fiddle.jshell.net/MwMEJ/show/:29:34)
ex1 instanceof NotImplementedError2 = true
ex1 instanceof Error = true
ex1.name = Error
ex1.message = NotImplementedError2 message

This confirmes the "problem" I ran into was the stack property of the error was the line number where new Error() was created, and not where the throw e occurred. However, that may be better that having the side effect of a NotImplementedError.prototype.name = "NotImplementedError" line affecting the Error object.

Also, notice with NotImplementedError2, when I don't set the .name explicitly, it is equal to "Error". However, as mentioned in the comments, because that version sets prototype to new Error(), I could set NotImplementedError2.prototype.name = "NotImplementedError2" and be OK.

Spring Hibernate - Could not obtain transaction-synchronized Session for current thread

In your xyz.DAOImpl.java

Do the following steps:

//Step-1: Set session factory

@Resource(name="sessionFactory")
private SessionFactory sessionFactory;

public void setSessionFactory(SessionFactory sf)
{
    this.sessionFactory = sf;
}

//Step-2: Try to get the current session, and catch the HibernateException exception.

//Step-3: If there are any HibernateException exception, then true to get openSession. 

try 
{
    //Step-2: Implementation
    session = sessionFactory.getCurrentSession();
} 
catch (HibernateException e) 
{
    //Step-3: Implementation
    session = sessionFactory.openSession();
}

Using ExcelDataReader to read Excel data starting from a particular cell

 
public static DataTable ConvertExcelToDataTable(string filePath, bool isXlsx = false)
{
    System.Text.Encoding.RegisterProvider(System.Text.CodePagesEncodingProvider.Instance);
    //open file and returns as Stream
        using (var stream = File.Open(filePath, FileMode.Open, FileAccess.Read))
        {
                using (var reader = ExcelReaderFactory.CreateReader(stream))
                {

                    var conf = new ExcelDataSetConfiguration
                    {
                        ConfigureDataTable = _ => new ExcelDataTableConfiguration
                        {
                            UseHeaderRow = true
                        }
                    };

                    var dataSet = reader.AsDataSet(conf);

                    // Now you can get data from each sheet by its index or its "name"
                    var dataTable = dataSet.Tables[0];

                    Console.WriteLine("Total no of rows  " + dataTable.Rows.Count);
                    Console.WriteLine("Total no of Columns  " + dataTable.Columns.Count);

                    return dataTable;

                }

        }
   
}

How to draw interactive Polyline on route google maps v2 android

I've created a couple of map tutorials that will cover what you need

Animating the map describes howto create polylines based on a set of LatLngs. Using Google APIs on your map : Directions and Places describes howto use the Directions API and animate a marker along the path.

Take a look at these 2 tutorials and the Github project containing the sample app.

It contains some tips to make your code cleaner and more efficient:

  • Using Google HTTP Library for more efficient API access and easy JSON handling.
  • Using google-map-utils library for maps-related functions (like decoding the polylines)
  • Animating markers

Setting multiple attributes for an element at once with JavaScript

Try this

function setAttribs(elm, ob) {
    //var r = [];
    //var i = 0;
    for (var z in ob) {
        if (ob.hasOwnProperty(z)) {
            try {
                elm[z] = ob[z];
            }
            catch (er) {
                elm.setAttribute(z, ob[z]);
            }
        }
    }
    return elm;
}

DEMO: HERE

retrieve data from db and display it in table in php .. see this code whats wrong with it?

In your while statement just replace mysql_fetch_row with mysql_fetch_array or mysql_fetch_assoc... whichever works...

How do you generate dynamic (parameterized) unit tests in Python?

I came across ParamUnittest the other day when looking at the source code for radon (example usage on the GitHub repository). It should work with other frameworks that extend TestCase (like Nose).

Here is an example:

import unittest
import paramunittest


@paramunittest.parametrized(
    ('1', '2'),
    #(4, 3),    <---- Uncomment to have a failing test
    ('2', '3'),
    (('4', ), {'b': '5'}),
    ((), {'a': 5, 'b': 6}),
    {'a': 5, 'b': 6},
)
class TestBar(TestCase):
    def setParameters(self, a, b):
        self.a = a
        self.b = b

    def testLess(self):
        self.assertLess(self.a, self.b)

Stop jQuery .load response from being cached

If you want to stick with Jquery's .load() method, add something unique to the URL like a JavaScript timestamp. "+new Date().getTime()". Notice I had to add an "&time=" so it does not alter your pid variable.

$('#searchButton').click(function() {
$('#inquiry').load('/portal/?f=searchBilling&pid=' + $('#query').val()+'&time='+new Date().getTime());            
});

What's sizeof(size_t) on 32-bit vs the various 64-bit data models?

size_t is defined by the C standard to be the unsigned integer return type of the sizeof operator (C99 6.3.5.4.4), and the argument of malloc and friends (C99 7.20.3.3 etc). The actual range is set such that the maximum (SIZE_MAX) is at least 65535 (C99 7.18.3.2).

However, this doesn't let us determine sizeof(size_t). The implementation is free to use any representation it likes for size_t - so there is no upper bound on size - and the implementation is also free to define a byte as 16-bits, in which case size_t can be equivalent to unsigned char.

Putting that aside, however, in general you'll have 32-bit size_t on 32-bit programs, and 64-bit on 64-bit programs, regardless of the data model. Generally the data model only affects static data; for example, in GCC:

`-mcmodel=small'
     Generate code for the small code model: the program and its
     symbols must be linked in the lower 2 GB of the address space.
     Pointers are 64 bits.  Programs can be statically or dynamically
     linked.  This is the default code model.

`-mcmodel=kernel'
     Generate code for the kernel code model.  The kernel runs in the
     negative 2 GB of the address space.  This model has to be used for
     Linux kernel code.

`-mcmodel=medium'
     Generate code for the medium model: The program is linked in the
     lower 2 GB of the address space but symbols can be located
     anywhere in the address space.  Programs can be statically or
     dynamically linked, but building of shared libraries are not
     supported with the medium model.

`-mcmodel=large'
     Generate code for the large model: This model makes no assumptions
     about addresses and sizes of sections.

You'll note that pointers are 64-bit in all cases; and there's little point to having 64-bit pointers but not 64-bit sizes, after all.

PHP check file extension

 
$file = $_FILES["file"] ["tmp_name"]; 
$check_ext = strtolower(pathinfo($file,PATHINFO_EXTENSION));
if ($check_ext == "fileext") {
    //code
}
else { 
    //code
}

What is the difference between the 'COPY' and 'ADD' commands in a Dockerfile?

COPY copies a file/directory from your host to your image.

ADD copies a file/directory from your host to your image, but can also fetch remote URLs, extract TAR files, etc...

Use COPY for simply copying files and/or directories into the build context.

Use ADD for downloading remote resources, extracting TAR files, etc..

Create space at the beginning of a UITextField

To create padding view for UITextField in Swift 5

func txtPaddingVw(txt:UITextField) {
    let paddingView = UIView(frame: CGRect(x: 0, y: 0, width: 5, height: 5))
    txt.leftViewMode = .always
    txt.leftView = paddingView
}

What size should TabBar images be?

According to my practice, I use the 40 x 40 for standard iPad tab bar item icon, 80 X 80 for retina.

From the Apple reference. https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/MobileHIG/BarIcons.html#//apple_ref/doc/uid/TP40006556-CH21-SW1

If you want to create a bar icon that looks like it's related to the iOS 7 icon family, use a very thin stroke to draw it. Specifically, a 2-pixel stroke (high resolution) works well for detailed icons and a 3-pixel stroke works well for less detailed icons.

Regardless of the icon’s visual style, create a toolbar or navigation bar icon in the following sizes:

About 44 x 44 pixels About 22 x 22 pixels (standard resolution) Regardless of the icon’s visual style, create a tab bar icon in the following sizes:

About 50 x 50 pixels (96 x 64 pixels maximum) About 25 x 25 pixels (48 x 32 pixels maximum) for standard resolution

Error 'LINK : fatal error LNK1123: failure during conversion to COFF: file invalid or corrupt' after installing Visual Studio 2012 Release Preview

+1 to user Short for an answer that worked for me!

I tried to do some debugging of this with msbuild /v:diag, and I'm seeing that MSBuild is trying to embed a manifest in the executable, with <somename>.dll.embed.manifest.res on the linker command line, where that is a resource file built from <somename>.dll.embed.manifest. But the manifest file is an empty Unicode text file. (That is, a two-byte file with the Unicode 0xFEFF prefix)

So the root problem seems to have something to do with that manifest file not being generated, or it being used when <somename>.dll.intermediate.manifest should have been used.

An alternate solution seems to be to turn off the "Embed Manifest" option under Properties, Manifest Tool, Input and Output.

How can I plot a confusion matrix?

enter image description here

you can use plt.matshow() instead of plt.imshow() or you can use seaborn module's heatmap (see documentation) to plot the confusion matrix

import seaborn as sn
import pandas as pd
import matplotlib.pyplot as plt
array = [[33,2,0,0,0,0,0,0,0,1,3], 
        [3,31,0,0,0,0,0,0,0,0,0], 
        [0,4,41,0,0,0,0,0,0,0,1], 
        [0,1,0,30,0,6,0,0,0,0,1], 
        [0,0,0,0,38,10,0,0,0,0,0], 
        [0,0,0,3,1,39,0,0,0,0,4], 
        [0,2,2,0,4,1,31,0,0,0,2],
        [0,1,0,0,0,0,0,36,0,2,0], 
        [0,0,0,0,0,0,1,5,37,5,1], 
        [3,0,0,0,0,0,0,0,0,39,0], 
        [0,0,0,0,0,0,0,0,0,0,38]]
df_cm = pd.DataFrame(array, index = [i for i in "ABCDEFGHIJK"],
                  columns = [i for i in "ABCDEFGHIJK"])
plt.figure(figsize = (10,7))
sn.heatmap(df_cm, annot=True)

Transfer data from one database to another database

if both databases are on same server and you want to transfer entire table (make copy of it) then use simple select into statement ...

select * into anotherDatabase..copyOfTable from oneDatabase..tableName

You can then write cursor top of sysobjects and copy entire set of tables that way.

If you want more complex data extraction & transformation, then use SSIS and build appropriate ETL in it.

In Unix, how do you remove everything in the current directory and below it?

It is correct that rm –rf . will remove everything in the current directly including any subdirectories and their content. The single dot (.) means the current directory. be carefull not to do rm -rf .. since the double dot (..) means the previous directory.

This being said, if you are like me and have multiple terminal windows open at the same time, you'd better be safe and use rm -ir . Lets look at the command arguments to understand why.

First, if you look at the rm command man page (man rm under most Unix) you notice that –r means "remove the contents of directories recursively". So, doing rm -r . alone would delete everything in the current directory and everything bellow it.

In rm –rf . the added -f means "ignore nonexistent files, never prompt". That command deletes all the files and directories in the current directory and never prompts you to confirm you really want to do that. -f is particularly dangerous if you run the command under a privilege user since you could delete the content of any directory without getting a chance to make sure that's really what you want.

On the otherhand, in rm -ri . the -i that replaces the -f means "prompt before any removal". This means you'll get a chance to say "oups! that's not what I want" before rm goes happily delete all your files.

In my early sysadmin days I did an rm -rf / on a system while logged with full privileges (root). The result was two days passed a restoring the system from backups. That's why I now employ rm -ri now.

How to do left join in Doctrine?

If you have an association on a property pointing to the user (let's say Credit\Entity\UserCreditHistory#user, picked from your example), then the syntax is quite simple:

public function getHistory($users) {
    $qb = $this->entityManager->createQueryBuilder();
    $qb
        ->select('a', 'u')
        ->from('Credit\Entity\UserCreditHistory', 'a')
        ->leftJoin('a.user', 'u')
        ->where('u = :user')
        ->setParameter('user', $users)
        ->orderBy('a.created_at', 'DESC');

    return $qb->getQuery()->getResult();
}

Since you are applying a condition on the joined result here, using a LEFT JOIN or simply JOIN is the same.

If no association is available, then the query looks like following

public function getHistory($users) {
    $qb = $this->entityManager->createQueryBuilder();
    $qb
        ->select('a', 'u')
        ->from('Credit\Entity\UserCreditHistory', 'a')
        ->leftJoin(
            'User\Entity\User',
            'u',
            \Doctrine\ORM\Query\Expr\Join::WITH,
            'a.user = u.id'
        )
        ->where('u = :user')
        ->setParameter('user', $users)
        ->orderBy('a.created_at', 'DESC');

    return $qb->getQuery()->getResult();
}

This will produce a resultset that looks like following:

array(
    array(
        0 => UserCreditHistory instance,
        1 => Userinstance,
    ),
    array(
        0 => UserCreditHistory instance,
        1 => Userinstance,
    ),
    // ...
)

Should black box or white box testing be the emphasis for testers?

"Both" has been stated above, and is the obvious answer...but IMO, white box testing goes far beyond developer unit testing (althoughI suppose it could depend on where you draw the line between white and black). For example, code coverage analysis is a common white box approach - i.e. run some scenarios or tests, and examine the results looking for holes in testing. Even if unit tests have 100% cc, measuring cc on common user scenarios can reveal code that may potentially need even more testing.

Another place where white box testing helps is examining data types, constants and other information to look for boundaries, special values, etc. For example, if an application has an input that takes a numeric input, a bb only approach could require the tester to "guess" at what values would be good for testing, whereas a wb approach may reveal that all values between 1-256 are treated one way, while larger values are treated another way...and perhaps the number 42 has yet another code path.

So, to answer the original question - both bb and wb are essential for good testing.

Appending to an existing string

Here's another way:

fist_segment = "hello,"
second_segment = "world."
complete_string = "#{first_segment} #{second_segment}"

How do I get IntelliJ to recognize common Python modules?

I got it to work after I unchecked the following options in the Run/Debug Configurations for main.py

Add content roots to PYTHONPATH

Add source roots to PYTHONPATH

This is after I had invalidated the cache and restarted.

Does Python have “private” variables in classes?

Private variables in python is more or less a hack: the interpreter intentionally renames the variable.

class A:
    def __init__(self):
        self.__var = 123
    def printVar(self):
        print self.__var

Now, if you try to access __var outside the class definition, it will fail:

 >>>x = A()
 >>>x.__var # this will return error: "A has no attribute __var"

 >>>x.printVar() # this gives back 123

But you can easily get away with this:

 >>>x.__dict__ # this will show everything that is contained in object x
               # which in this case is something like {'_A__var' : 123}

 >>>x._A__var = 456 # you now know the masked name of private variables
 >>>x.printVar() # this gives back 456

You probably know that methods in OOP are invoked like this: x.printVar() => A.printVar(x), if A.printVar() can access some field in x, this field can also be accessed outside A.printVar()...after all, functions are created for reusability, there is no special power given to the statements inside.

The game is different when there is a compiler involved (privacy is a compiler level concept). It know about class definition with access control modifiers so it can error out if the rules are not being followed at compile time

Postgres: SQL to list table foreign keys

 
 SELECT 
    conrelid::regclass AS table_from,
    conname,
    pg_get_constraintdef(oid) as condef    
    FROM pg_catalog.pg_constraint r

will also work for all constraints. E.g. with pysql: enter image description here

jQuery same click event for multiple elements

 
$('.class1, .class2').click(some_function);

Make sure you put a space like $('.class1,space here.class2') or else it won't work.

Why do we assign a parent reference to the child object in Java?

I know this is a very old thread but I came across the same doubt once.

So the concept of Parent parent = new Child(); has something to do with early and late binding in java.

The binding of private, static and final methods happen at the compile as they cannot be overridden and the normal method calls and overloaded methods are example of early binding.

Consider the example:

class Vehicle
{
    int value = 100;
    void start() {
        System.out.println("Vehicle Started");
    }

    static void stop() {
        System.out.println("Vehicle Stopped");
    }
}

class Car extends Vehicle {

    int value = 1000;

    @Override
    void start() {
        System.out.println("Car Started");
    }

    static void stop() {
        System.out.println("Car Stopped");
    }

    public static void main(String args[]) {

        // Car extends Vehicle
        Vehicle vehicle = new Car();
        System.out.println(vehicle.value);
        vehicle.start();
        vehicle.stop();
    }
}

Output: 100

Car Started

Vehicle Stopped

This is happening because stop() is a static method and cannot be overridden. So binding of stop() happens at compile time and start() is non-static is being overridden in child class. So, the information about type of object is available at the run time only(late binding) and hence the start() method of Car class is called.

Also in this code the vehicle.value gives us 100 as the output because variable initialization doesn't come under late binding. Method overriding is one of the ways in which java supports run time polymorphism.

  • When an overridden method is called through a superclass reference, Java determines which version(superclass/subclasses) of that method is to be executed based upon the type of the object being referred to at the time the call occurs. Thus, this determination is made at run time.
  • At run-time, it depends on the type of the object being referred to (not the type of the reference variable) that determines which version of an overridden method will be executed

I hope this answers where Parent parent = new Child(); is important and also why you weren't able to access the child class variable using the above reference.

nginx error:"location" directive is not allowed here in /etc/nginx/nginx.conf:76

Since your server already includes the sites-enabled folder ( notice the include /etc/nginx/sites-enabled/* line ), then you better use that.

  1. Create a file inside /etc/nginx/sites-available and call it whatever you want, I'll call it django since it's a djanog server

    sudo touch /etc/nginx/sites-available/django

  2. Then create a symlink that points to it

    sudo ln -s /etc/nginx/sites-available/django /etc/nginx/sites-enabled

  3. Then edit that file with whatever file editor you use, vim or nano or whatever and create the server inside it

    server {
    # hostname or ip or multiple separated by spaces
    server_name localhost example.com 192.168.1.1; #change to your setting
    location / {
        root /home/techcee/scrapbook/local/lib/python2.7/site-packages/django/__init__.pyc/;
    }
}

  4. Restart or reload nginx settings

    sudo service nginx reload

Note I believe that your configuration like this probably won't work yet because you need to pass it to a fastcgi server or something, but at least this is how you could create a valid server

How to return 2 values from a Java method?

 
public class Mulretun
{
    public String name;;
    public String location;
    public String[] getExample()
    {
        String ar[] = new String[2];
        ar[0]="siva";
        ar[1]="dallas";
        return ar; //returning two values at once
    }
    public static void main(String[] args)
    {
        Mulretun m=new Mulretun();
        String ar[] =m.getExample();
        int i;
        for(i=0;i<ar.length;i++)
        System.out.println("return values are: " + ar[i]);      

    }
}

o/p:
return values are: siva
return values are: dallas

HTML5 and frameborder

This works

iframe{
    border-width: 0px;
}

How to select between brackets (or quotes or ...) in Vim?

For selecting within single quotes use vi'.

For selecting within parenthesis use vi(.

Can a table have two foreign keys?

Yes, a table have one or many foreign keys and each foreign keys hava a different parent table.

selenium get current url after loading a page

It's been a little while since I coded with selenium, but your code looks ok to me. One thing to note is that if the element is not found, but the timeout is passed, I think the code will continue to execute. So you can do something like this:

boolean exists = driver.findElements(By.xpath("//*[@id='someID']")).size() != 0

What does the above boolean return? And are you sure selenium actually navigates to the expected page? (That may sound like a silly question but are you actually watching the pages change... selenium can be run remotely you know...)

Xcode process launch failed: Security

SETTINGS -> GENERAL -> Profiles & Device Management choose the developer profile and push Trust.

if you do not have Profiles & Device Management menu you have to enroll your device on beta.apple.com and download the profile from Safari.

  1. install the profile
  2. Restart your device
  3. tap on the developer profile and trust.

You are all set.

How to send a “multipart/form-data” POST in Android with Volley

Complete Multipart Request with Upload Progress

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Map;

import org.apache.http.HttpEntity;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.mime.HttpMultipartMode;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.util.CharsetUtils;

import com.android.volley.AuthFailureError;
import com.android.volley.NetworkResponse;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyLog;
import com.beusoft.app.AppContext;

public class MultipartRequest extends Request<String> {

    MultipartEntityBuilder entity = MultipartEntityBuilder.create();
    HttpEntity httpentity;
    private String FILE_PART_NAME = "files";

    private final Response.Listener<String> mListener;
    private final File mFilePart;
    private final Map<String, String> mStringPart;
    private Map<String, String> headerParams;
    private final MultipartProgressListener multipartProgressListener;
    private long fileLength = 0L;

    public MultipartRequest(String url, Response.ErrorListener errorListener,
            Response.Listener<String> listener, File file, long fileLength,
            Map<String, String> mStringPart,
            final Map<String, String> headerParams, String partName,
            MultipartProgressListener progLitener) {
        super(Method.POST, url, errorListener);

        this.mListener = listener;
        this.mFilePart = file;
        this.fileLength = fileLength;
        this.mStringPart = mStringPart;
        this.headerParams = headerParams;
        this.FILE_PART_NAME = partName;
        this.multipartProgressListener = progLitener;

        entity.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
        try {
            entity.setCharset(CharsetUtils.get("UTF-8"));
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        buildMultipartEntity();
        httpentity = entity.build();
    }

    // public void addStringBody(String param, String value) {
    // if (mStringPart != null) {
    // mStringPart.put(param, value);
    // }
    // }

    private void buildMultipartEntity() {
        entity.addPart(FILE_PART_NAME, new FileBody(mFilePart, ContentType.create("image/gif"), mFilePart.getName()));
        if (mStringPart != null) {
            for (Map.Entry<String, String> entry : mStringPart.entrySet()) {
                entity.addTextBody(entry.getKey(), entry.getValue());
            }
        }
    }

    @Override
    public String getBodyContentType() {
        return httpentity.getContentType().getValue();
    }

    @Override
    public byte[] getBody() throws AuthFailureError {
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        try {
            httpentity.writeTo(new CountingOutputStream(bos, fileLength,
                    multipartProgressListener));
        } catch (IOException e) {
            VolleyLog.e("IOException writing to ByteArrayOutputStream");
        }
        return bos.toByteArray();
    }

    @Override
    protected Response<String> parseNetworkResponse(NetworkResponse response) {

        try {
//          System.out.println("Network Response "+ new String(response.data, "UTF-8"));
            return Response.success(new String(response.data, "UTF-8"),
                    getCacheEntry());
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
            // fuck it, it should never happen though
            return Response.success(new String(response.data), getCacheEntry());
        }
    }

    @Override
    protected void deliverResponse(String response) {
        mListener.onResponse(response);
    }

//Override getHeaders() if you want to put anything in header

    public static interface MultipartProgressListener {
        void transferred(long transfered, int progress);
    }

    public static class CountingOutputStream extends FilterOutputStream {
        private final MultipartProgressListener progListener;
        private long transferred;
        private long fileLength;

        public CountingOutputStream(final OutputStream out, long fileLength,
                final MultipartProgressListener listener) {
            super(out);
            this.fileLength = fileLength;
            this.progListener = listener;
            this.transferred = 0;
        }

        public void write(byte[] b, int off, int len) throws IOException {
            out.write(b, off, len);
            if (progListener != null) {
                this.transferred += len;
                int prog = (int) (transferred * 100 / fileLength);
                this.progListener.transferred(this.transferred, prog);
            }
        }

        public void write(int b) throws IOException {
            out.write(b);
            if (progListener != null) {
                this.transferred++;
                int prog = (int) (transferred * 100 / fileLength);
                this.progListener.transferred(this.transferred, prog);
            }
        }

    }
}

Sample Usage

protected <T> void uploadFile(final String tag, final String url,
            final File file, final String partName,         
            final Map<String, String> headerParams,
            final Response.Listener<String> resultDelivery,
            final Response.ErrorListener errorListener,
            MultipartProgressListener progListener) {
        AZNetworkRetryPolicy retryPolicy = new AZNetworkRetryPolicy();

        MultipartRequest mr = new MultipartRequest(url, errorListener,
                resultDelivery, file, file.length(), null, headerParams,
                partName, progListener);

        mr.setRetryPolicy(retryPolicy);
        mr.setTag(tag);

        Volley.newRequestQueue(this).add(mr);

    }

Java: Date from unix timestamp

Looks like Calendar is the new way to go:

Calendar mydate = Calendar.getInstance();
mydate.setTimeInMillis(timestamp*1000);
out.println(mydate.get(Calendar.DAY_OF_MONTH)+"."+mydate.get(Calendar.MONTH)+"."+mydate.get(Calendar.YEAR));

The last line is just an example how to use it, this one would print eg "14.06.2012".

If you have used System.currentTimeMillis() to save the Timestamp you don't need the "*1000" part.

If you have the timestamp in a string you need to parse it first as a long: Long.parseLong(timestamp).

https://docs.oracle.com/javase/7/docs/api/java/util/Calendar.html

RegEx to parse or validate Base64 data

Here's an alternative regular expression:

^(?=(.{4})*$)[A-Za-z0-9+/]*={0,2}$

It satisfies the following conditions:

  • The string length must be a multiple of four - (?=^(.{4})*$)
  • The content must be alphanumeric characters or + or / - [A-Za-z0-9+/]*
  • It can have up to two padding (=) characters on the end - ={0,2}
  • It accepts empty strings

Intro to GPU programming

I think the others have answered your second question. As for the first, the "Hello World" of CUDA, I don't think there is a set standard, but personally, I'd recommend a parallel adder (i.e. a programme that sums N integers).

If you look the "reduction" example in the NVIDIA SDK, the superficially simple task can be extended to demonstrate numerous CUDA considerations such as coalesced reads, memory bank conflicts and loop unrolling.

See this presentation for more info:

http://www.gpgpu.org/sc2007/SC07_CUDA_5_Optimization_Harris.pdf

UIButton: set image for selected-highlighted state

In my case, I have to change the UIButton.Type from .custom to .system

And:

button.setImage(UIImage(named: "unchecked"), for: .normal)
button.setImage(UIImage(named: "checked"), for: [.selected, .highlighted])

When handling tapping:

button.isSelected = !button.isSelected

Laravel eloquent update record without loading from database

The common way is to load the row to update:

$post = Post::find($id);

I your case

$post = Post::find(3);
$post->title = "Updated title";
$post->save();

But in one step (just update) you can do this:

$affectedRows = Post::where("id", 3)->update(["title" => "Updated title"]);

Python for and if on one line

When you perform

>>> [(i) for i in my_list if i=="two"]

i is iterated through the list my_list. As the list comprehension finishes evaluation, i is assigned to the last item in iteration, which is "three".

Difference between left join and right join in SQL Server

Your two statements are equivalent.

Most people only use LEFT JOIN since it seems more intuitive, and it's universal syntax - I don't think all RDBMS support RIGHT JOIN.

Storing Images in PostgreSQL

If your images are small, consider storing them as base64 in a plain text field.

The reason is that while base64 has an overhead of 33%, with compression that mostly goes away. (See What is the space overhead of Base64 encoding?) Your database will be bigger, but the packets your webserver sends to the client won't be. In html, you can inline base64 in an <img src=""> tag, which can possibly simplify your app because you won't have to serve up the images as binary in a separate browser fetch. Handling images as text also simplifies things when you have to send/receive json, which doesn't handle binary very well.

Yes, I understand you could store the binary in the database and convert it to/from text on the way in and out of the database, but sometimes ORMs make that a hassle. It can be simpler just to treat it as straight text just like all your other fields.

This is definitely the right way to handle thumbnails.

(OP's images are not small, so this is not really an answer to his question.)

Check if an HTML input element is empty or has no value entered by user

You want:

if (document.getElementById('customx').value === ""){
    //do something
}

The value property will give you a string value and you need to compare that against an empty string.

How to install Openpyxl with pip

(optional) Install git for windows (https://git-scm.com/) to get git bash. Git bash is much more similar to Linux terminal than Windows cmd.

Install Anaconda 3

https://www.anaconda.com/download/

It should set itself into Windows PATH. Restart your PC. Then pip should work in your cmd

Then in cmd (or git bash), run command

pip install openpyxl

Plot a bar using matplotlib using a dictionary

It's a little simpler than most answers here suggest:

import matplotlib.pyplot as plt

D = {u'Label1':26, u'Label2': 17, u'Label3':30}
plt.bar(*zip(*D.items()))
plt.show()

enter image description here

Submit form using AJAX and jQuery

First give your form an id attribute, then use code like this:

$(document).ready( function() {
  var form = $('#my_awesome_form');

  form.find('select:first').change( function() {
    $.ajax( {
      type: "POST",
      url: form.attr( 'action' ),
      data: form.serialize(),
      success: function( response ) {
        console.log( response );
      }
    } );
  } );

} );

So this code uses .serialize() to pull out the relevant data from the form. It also assumes the select you care about is the first one in the form.

For future reference, the jQuery docs are very, very good.

Understanding the map function

Simplifying a bit, you can imagine map() doing something like this:

def mymap(func, lst):
    result = []
    for e in lst:
        result.append(func(e))
    return result

As you can see, it takes a function and a list, and returns a new list with the result of applying the function to each of the elements in the input list. I said "simplifying a bit" because in reality map() can process more than one iterable:

If additional iterable arguments are passed, function must take that many arguments and is applied to the items from all iterables in parallel. If one iterable is shorter than another it is assumed to be extended with None items.

For the second part in the question: What role does this play in making a Cartesian product? well, map() could be used for generating the cartesian product of a list like this:

lst = [1, 2, 3, 4, 5]

from operator import add
reduce(add, map(lambda i: map(lambda j: (i, j), lst), lst))

... But to tell the truth, using product() is a much simpler and natural way to solve the problem:

from itertools import product
list(product(lst, lst))

Either way, the result is the cartesian product of lst as defined above:

[(1, 1), (1, 2), (1, 3), (1, 4), (1, 5),
 (2, 1), (2, 2), (2, 3), (2, 4), (2, 5),
 (3, 1), (3, 2), (3, 3), (3, 4), (3, 5),
 (4, 1), (4, 2), (4, 3), (4, 4), (4, 5),
 (5, 1), (5, 2), (5, 3), (5, 4), (5, 5)]

How can I install an older version of a package via NuGet?

Now, it's very much simplified in Visual Studio 2015 and later. You can do downgrade / upgrade within the User interface itself, without executing commands in the Package Manager Console.

  1. Right click on your project and *go to Manage NuGet Packages.

  2. Look at the below image.

    • Select your Package and Choose the Version, which you wanted to install.

NuGet Package Manager window of Project

Very very simple, isn't it? :)

$(document).ready shorthand

The multi-framework safe shorthand for ready is:

jQuery(function($, undefined) {
    // $ is guaranteed to be short for jQuery in this scope
    // undefined is provided because it could have been overwritten elsewhere
});

This is because jQuery isn't the only framework that uses the $ and undefined variables

Android getActivity() is undefined

This is because you're using getActivity() inside an inner class. Try using:

SherlockFragmentActivity.this.getActivity()

instead, though there's really no need for the getActivity() part. In your case, SherlockFragmentActivity .this should suffice.

Regex - how to match everything except a particular pattern

If you want to match a word A in a string and not to match a word B. For example: If you have a text:

1. I have a two pets - dog and a cat
2. I have a pet - dog

If you want to search for lines of text that HAVE a dog for a pet and DOESN'T have cat you can use this regular expression:

^(?=.*?\bdog\b)((?!cat).)*$

It will find only second line:

2. I have a pet - dog

Change window location Jquery

you can use the new push/pop state functions in the history manipulation API.

Comparing two integer arrays in Java

 
public static void compareArrays(int[] array1, int[] array2) {
        boolean b = true;
        if (array1 != null && array2 != null){
          if (array1.length != array2.length)
              b = false;
          else
              for (int i = 0; i < array2.length; i++) {
                  if (array2[i] != array1[i]) {
                      b = false;    
                  }                 
            }
        }else{
          b = false;
        }
        System.out.println(b);
    }

Remove duplicates from a List<T> in C#

Another way in .Net 2.0

    static void Main(string[] args)
    {
        List<string> alpha = new List<string>();

        for(char a = 'a'; a <= 'd'; a++)
        {
            alpha.Add(a.ToString());
            alpha.Add(a.ToString());
        }

        Console.WriteLine("Data :");
        alpha.ForEach(delegate(string t) { Console.WriteLine(t); });

        alpha.ForEach(delegate (string v)
                          {
                              if (alpha.FindAll(delegate(string t) { return t == v; }).Count > 1)
                                  alpha.Remove(v);
                          });

        Console.WriteLine("Unique Result :");
        alpha.ForEach(delegate(string t) { Console.WriteLine(t);});
        Console.ReadKey();
    }

Simple VBA selection: Selecting 5 cells to the right of the active cell

This copies the 5 cells to the right of the activecell. If you have a range selected, the active cell is the top left cell in the range.

Sub Copy5CellsToRight()
    ActiveCell.Offset(, 1).Resize(1, 5).Copy
End Sub

If you want to include the activecell in the range that gets copied, you don't need the offset:

Sub ExtendAndCopy5CellsToRight()
    ActiveCell.Resize(1, 6).Copy
End Sub

Note that you don't need to select before copying.

Default parameters with C++ constructors

One more thing to consider is whether or not the class could be used in an array:

foo bar[400];

In this scenario, there is no advantage to using the default parameter.

This would certainly NOT work:

foo bar("david", 34)[400]; // NOPE

How to set text color in submit button?

you try this:

<input type="submit" style="font-face: 'Comic Sans MS'; font-size: larger; color: teal; background-color: #FFFFC0; border: 3pt ridge lightgrey" value=" Send Me! ">

Python read JSON file and modify

I would like to present a modified version of Vadim's solution. It helps to deal with asynchronous requests to write/modify json file. I know it wasn't a part of the original question but might be helpful for others.

In case of asynchronous file modification os.remove(filename) will raise FileNotFoundError if requests emerge frequently. To overcome this problem you can create temporary file with modified content and then rename it simultaneously replacing old version. This solution works fine both for synchronous and asynchronous cases.

import os, json, uuid

filename = 'data.json'
with open(filename, 'r') as f:
    data = json.load(f)
    data['id'] = 134 # <--- add `id` value.
    # add, remove, modify content

# create randomly named temporary file to avoid 
# interference with other thread/asynchronous request
tempfile = os.path.join(os.path.dirname(filename), str(uuid.uuid4()))
with open(tempfile, 'w') as f:
    json.dump(data, f, indent=4)

# rename temporary file replacing old file
os.rename(tempfile, filename)

What does "&" at the end of a linux command mean?

The & makes the command run in the background.

From man bash:

If a command is terminated by the control operator &, the shell executes the command in the background in a subshell. The shell does not wait for the command to finish, and the return status is 0.

PHP remove commas from numeric strings

Not tested, but probably something like if(preg_match("/^[0-9,]+$/", $a)) $a = str_replace(...)

Do it the other way around:

$a = "1,435";
$b = str_replace( ',', '', $a );

if( is_numeric( $b ) ) {
    $a = $b;
}

The easiest would be:

$var = intval(preg_replace('/[^\d.]/', '', $var));

or if you need float:

$var = floatval(preg_replace('/[^\d.]/', '', $var));

HTML table with fixed headers?

A more refined pure CSS scrolling table

All of the pure CSS solutions I've seen so far-- clever though they may be-- lack a certain level of polish, or just don't work right in some situations. So, I decided to create my own...

Features:

  • It's pure CSS, so no jQuery required (or any JavaScript code at all, for that matter)
  • You can set the table width to a percent (a.k.a. "fluid") or a fixed value, or let the content determine its width (a.k.a. "auto")
  • Column widths can also be fluid, fixed, or auto.
  • Columns will never become misaligned with headers due to horizontal scrolling (a problem that occurs in every other CSS-based solution I've seen that doesn't require fixed widths).
  • Compatible with all of the popular desktop browsers, including Internet Explorer back to version 8
  • Clean, polished appearance; no sloppy-looking 1-pixel gaps or misaligned borders; looks the same in all browsers

Here are a couple of fiddles that show the fluid and auto width options:

  • Fluid Width and Height (adapts to screen size): jsFiddle (Note that the scrollbar only shows up when needed in this configuration, so you may have to shrink the frame to see it)

  • Auto Width, Fixed Height (easier to integrate with other content): jsFiddle

The Auto Width, Fixed Height configuration probably has more use cases, so I'll post the code below.

_x000D_
_x000D_ 
/* The following 'html' and 'body' rule sets are required only
   if using a % width or height*/

/*html {
  width: 100%;
  height: 100%;
}*/

body {
  box-sizing: border-box;
  width: 100%;
  height: 100%;
  margin: 0;
  padding: 0 20px 0 20px;
  text-align: center;
}
.scrollingtable {
  box-sizing: border-box;
  display: inline-block;
  vertical-align: middle;
  overflow: hidden;
  width: auto; /* If you want a fixed width, set it here, else set to auto */
  min-width: 0/*100%*/; /* If you want a % width, set it here, else set to 0 */
  height: 188px/*100%*/; /* Set table height here; can be fixed value or % */
  min-height: 0/*104px*/; /* If using % height, make this large enough to fit scrollbar arrows + caption + thead */
  font-family: Verdana, Tahoma, sans-serif;
  font-size: 16px;
  line-height: 20px;
  padding: 20px 0 20px 0; /* Need enough padding to make room for caption */
  text-align: left;
  color: black;
}
.scrollingtable * {box-sizing: border-box;}
.scrollingtable > div {
  position: relative;
  border-top: 1px solid black;
  height: 100%;
  padding-top: 20px; /* This determines column header height */
}
.scrollingtable > div:before {
  top: 0;
  background: cornflowerblue; /* Header row background color */
}
.scrollingtable > div:before,
.scrollingtable > div > div:after {
  content: "";
  position: absolute;
  z-index: -1;
  width: 100%;
  height: 100%;
  left: 0;
}
.scrollingtable > div > div {
  min-height: 0/*43px*/; /* If using % height, make this large
                            enough to fit scrollbar arrows */
  max-height: 100%;
  overflow: scroll/*auto*/; /* Set to auto if using fixed
                               or % width; else scroll */
  overflow-x: hidden;
  border: 1px solid black; /* Border around table body */
}
.scrollingtable > div > div:after {background: white;} /* Match page background color */
.scrollingtable > div > div > table {
  width: 100%;
  border-spacing: 0;
  margin-top: -20px; /* Inverse of column header height */
  /*margin-right: 17px;*/ /* Uncomment if using % width */
}
.scrollingtable > div > div > table > caption {
  position: absolute;
  top: -20px; /*inverse of caption height*/
  margin-top: -1px; /*inverse of border-width*/
  width: 100%;
  font-weight: bold;
  text-align: center;
}
.scrollingtable > div > div > table > * > tr > * {padding: 0;}
.scrollingtable > div > div > table > thead {
  vertical-align: bottom;
  white-space: nowrap;
  text-align: center;
}
.scrollingtable > div > div > table > thead > tr > * > div {
  display: inline-block;
  padding: 0 6px 0 6px; /*header cell padding*/
}
.scrollingtable > div > div > table > thead > tr > :first-child:before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  height: 20px; /*match column header height*/
  border-left: 1px solid black; /*leftmost header border*/
}
.scrollingtable > div > div > table > thead > tr > * > div[label]:before,
.scrollingtable > div > div > table > thead > tr > * > div > div:first-child,
.scrollingtable > div > div > table > thead > tr > * + :before {
  position: absolute;
  top: 0;
  white-space: pre-wrap;
  color: white; /*header row font color*/
}
.scrollingtable > div > div > table > thead > tr > * > div[label]:before,
.scrollingtable > div > div > table > thead > tr > * > div[label]:after {content: attr(label);}
.scrollingtable > div > div > table > thead > tr > * + :before {
  content: "";
  display: block;
  min-height: 20px; /* Match column header height */
  padding-top: 1px;
  border-left: 1px solid black; /* Borders between header cells */
}
.scrollingtable .scrollbarhead {float: right;}
.scrollingtable .scrollbarhead:before {
  position: absolute;
  width: 100px;
  top: -1px; /* Inverse border-width */
  background: white; /* Match page background color */
}
.scrollingtable > div > div > table > tbody > tr:after {
  content: "";
  display: table-cell;
  position: relative;
  padding: 0;
  border-top: 1px solid black;
  top: -1px; /* Inverse of border width */
}
.scrollingtable > div > div > table > tbody {vertical-align: top;}
.scrollingtable > div > div > table > tbody > tr {background: white;}
.scrollingtable > div > div > table > tbody > tr > * {
  border-bottom: 1px solid black;
  padding: 0 6px 0 6px;
  height: 20px; /* Match column header height */
}
.scrollingtable > div > div > table > tbody:last-of-type > tr:last-child > * {border-bottom: none;}
.scrollingtable > div > div > table > tbody > tr:nth-child(even) {background: gainsboro;} /* Alternate row color */
.scrollingtable > div > div > table > tbody > tr > * + * {border-left: 1px solid black;} /* Borders between body cells */
_x000D_ 
<div class="scrollingtable">
  <div>
    <div>
      <table>
        <caption>Top Caption</caption>
        <thead>
          <tr>
            <th><div label="Column 1"/></th>
            <th><div label="Column 2"/></th>
            <th><div label="Column 3"/></th>
            <th>
              <!-- More versatile way of doing column label; requires two identical copies of label -->
              <div><div>Column 4</div><div>Column 4</div></div>
            </th>
            <th class="scrollbarhead"/> <!-- ALWAYS ADD THIS EXTRA CELL AT END OF HEADER ROW -->
          </tr>
        </thead>
        <tbody>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
          <tr><td>Lorem ipsum</td><td>Dolor</td><td>Sit</td><td>Amet consectetur</td></tr>
        </tbody>
      </table>
    </div>
    Faux bottom caption
  </div>
</div>

<!--[if lte IE 9]><style>.scrollingtable > div > div > table {margin-right: 17px;}</style><![endif]-->
_x000D_
_x000D_
_x000D_

The method I used to freeze the header row is similar to d-Pixie's, so refer to his post for an explanation. There were a slew of bugs and limitations with that technique that could only be fixed with heaps of additional CSS and an extra div container or two.

Converting String to Int using try/except in Python

Here it is:

s = "123"
try:
  i = int(s)
except ValueError as verr:
  pass # do job to handle: s does not contain anything convertible to int
except Exception as ex:
  pass # do job to handle: Exception occurred while converting to int

PHP7 : install ext-dom issue

For CentOS, RHEL, Fedora:

$ yum search php-xml
============================================================================================================ N/S matched: php-xml ============================================================================================================
php-xml.x86_64 : A module for PHP applications which use XML
php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php-xmlseclibs.noarch : PHP library for XML Security
php54-php-xml.x86_64 : A module for PHP applications which use XML
php54-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php55-php-xml.x86_64 : A module for PHP applications which use XML
php55-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php56-php-xml.x86_64 : A module for PHP applications which use XML
php56-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php70-php-xml.x86_64 : A module for PHP applications which use XML
php70-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php71-php-xml.x86_64 : A module for PHP applications which use XML
php71-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php72-php-xml.x86_64 : A module for PHP applications which use XML
php72-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol
php73-php-xml.x86_64 : A module for PHP applications which use XML
php73-php-xmlrpc.x86_64 : A module for PHP applications which use the XML-RPC protocol

Then select the php-xml version matching your php version:

# php -v
PHP 7.2.11 (cli) (built: Oct 10 2018 10:00:29) ( NTS )
Copyright (c) 1997-2018 The PHP Group
Zend Engine v3.2.0, Copyright (c) 1998-2018 Zend Technologies

# sudo yum install -y php72-php-xml.x86_64

Android canvas draw rectangle

Create a new class MyView, Which extends View. Override the onDraw(Canvas canvas) method to draw rectangle on Canvas.

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.View;

public class MyView extends View {

 Paint paint;
 Path path;

 public MyView(Context context) {
  super(context);
  init();
 }

 public MyView(Context context, AttributeSet attrs) {
  super(context, attrs);
  init();
 }

 public MyView(Context context, AttributeSet attrs, int defStyle) {
  super(context, attrs, defStyle);
  init();
 }

 private void init(){
  paint = new Paint();
  paint.setColor(Color.BLUE);
  paint.setStrokeWidth(10);
  paint.setStyle(Paint.Style.STROKE);

 }

 @Override
 protected void onDraw(Canvas canvas) {
  // TODO Auto-generated method stub
  super.onDraw(canvas);

  canvas.drawRect(30, 50, 200, 350, paint);
  canvas.drawRect(100, 100, 300, 400, paint);
  //drawRect(left, top, right, bottom, paint)

 }

}

Then Move your Java activity to setContentView() using our custom View, MyView.Call this way.

    public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(new MyView(this));
  }

For more details you can visit here

http://developer.android.com/reference/android/graphics/Canvas.html

How to set min-height for bootstrap container

Have you tried height: auto; on your .container div?

Here is a fiddle, if you change img height, container height will adjust to it.

EDIT

So if you "can't" change the inline min-height, you can overwrite the inline style with an !important parameter. It's not the cleanest way, but it solves your problem.

add to your .containerclass this line

min-height:0px !important;

I've updated my fiddle to give you an example.

Find files with size in Unix

Assuming you have GNU find:

find . -size +10000k -printf '%s %f\n'

If you want a constant width for the size field, you can do something like:

find . -size +10000k -printf '%10s %f\n'

Note that -size +1000k selects files of at least 10,240,000 bytes (k is 1024, not 1000). You said in a comment that you want files bigger than 1M; if that's 1024*1024 bytes, then this:

find . -size +1M ...

will do the trick -- except that it will also print the size and name of files that are exactly 1024*1024 bytes. If that matters, you could use:

find . -size +1048575c ...

You need to decide just what criterion you want.

Adding text to a cell in Excel using VBA

You could do

[A1].Value = "'O1/01/13 00:00"

if you really mean to add it as text (note the apostrophe as the first character).

The [A1].Value is VBA shorthand for Range("A1").Value.

If you want to enter a date, you could instead do (edited order with thanks to @SiddharthRout):

[A1].NumberFormat = "mm/dd/yyyy hh:mm;@"
[A1].Value = DateValue("01/01/2013 00:00")

Difference between git checkout --track origin/branch and git checkout -b branch origin/branch

There is no difference at all!

1) git checkout -b branch origin/branch

If there is no --track and no --no-track, --track is assumed as default. The default can be changed with the setting branch.autosetupmerge.

In effect, 1) behaves like git checkout -b branch --track origin/branch.

2) git checkout --track origin/branch

“As a convenience”, --track without -b implies -b and the argument to -b is guessed to be “branch”. The guessing is driven by the configuration variable remote.origin.fetch.

In effect, 2) behaves like git checkout -b branch --track origin/branch.

As you can see: no difference.

But it gets even better:

3) git checkout branch

is also equivalent to git checkout -b branch --track origin/branch if “branch” does not exist yet but “origin/branch” does1.

All three commands set the “upstream” of “branch” to be “origin/branch” (or they fail).

Upstream is used as reference point of argument-less git status, git push, git merge and thus git pull (if configured like that (which is the default or almost the default)).

E.g. git status tells you how far behind or ahead you are of upstream, if one is configured.

git push is configured to push the current branch upstream by default2 since git 2.0.

1 ...and if “origin” is the only remote having “branch”
2 the default (named “simple”) also enforces for both branch names to be equal

jQuery multiple events to trigger the same function

I was looking for a way to get the event type when jQuery listens for several events at once, and Google put me here.

So, for those interested, event.type is my answer :

$('#element').on('keyup keypress blur change', function(event) {
    alert(event.type); // keyup OR keypress OR blur OR change
});

More info in the jQuery doc.

Provide an image for WhatsApp link sharing

You need the following tags to get a WhatsApp image preview:

<meta property="og:title" content="Website name" />
<meta property="og:type" content="website" />
<meta property="og:url" content="https://url.com/" />
<meta property="og:description" content="Website description" />
<meta property="og:image" content="image.png" />
<meta property="og:image:width" content="600" />
<meta property="og:image:height" content="600" />

As Facebook docs says, if you specify the og:image size it will be fetched fastly instead of asynchronously otherwise.

PNG is recommended for image format. 600x600 pixels at least is recommended.

Get the value of checked checkbox?

Use this:

alert($(".messageCheckbox").is(":checked").val())

This assumes the checkboxes to check have the class "messageCheckbox", otherwise you would have to do a check if the input is the checkbox type, etc.

How does numpy.histogram() work?

Another useful thing to do with numpy.histogram is to plot the output as the x and y coordinates on a linegraph. For example:

arr = np.random.randint(1, 51, 500)
y, x = np.histogram(arr, bins=np.arange(51))
fig, ax = plt.subplots()
ax.plot(x[:-1], y)
fig.show()

enter image description here

This can be a useful way to visualize histograms where you would like a higher level of granularity without bars everywhere. Very useful in image histograms for identifying extreme pixel values.

Socket.IO - how do I get a list of connected sockets/clients?

Socket.io 1.4

Object.keys(io.sockets.sockets); gives you all the connected sockets.

Socket.io 1.0 As of socket.io 1.0, the actual accepted answer isn't valid anymore. So I made a small function that I use as a temporary fix :

function findClientsSocket(roomId, namespace) {
    var res = []
    // the default namespace is "/"
    , ns = io.of(namespace ||"/");

    if (ns) {
        for (var id in ns.connected) {
            if(roomId) {
                var index = ns.connected[id].rooms.indexOf(roomId);
                if(index !== -1) {
                    res.push(ns.connected[id]);
                }
            } else {
                res.push(ns.connected[id]);
            }
        }
    }
    return res;
}

Api for No namespace becomes 

// var clients = io.sockets.clients();
// becomes : 
var clients = findClientsSocket();

// var clients = io.sockets.clients('room');
// all users from room `room`
// becomes
var clients = findClientsSocket('room');

Api for a namespace becomes :

// var clients = io.of('/chat').clients();
// becomes
var clients = findClientsSocket(null, '/chat');

// var clients = io.of('/chat').clients('room');
// all users from room `room`
// becomes
var clients = findClientsSocket('room', '/chat');

Also see this related question, in which I give a function that returns the sockets for a given room.

function findClientsSocketByRoomId(roomId) {
var res = []
, room = io.sockets.adapter.rooms[roomId];
if (room) {
    for (var id in room) {
    res.push(io.sockets.adapter.nsp.connected[id]);
    }
}
return res;
}

Socket.io 0.7

API for no namespace:

var clients = io.sockets.clients();
var clients = io.sockets.clients('room'); // all users from room `room`

For a namespace

var clients = io.of('/chat').clients();
var clients = io.of('/chat').clients('room'); // all users from room `room`

Note: Since it seems the socket.io API is prone to breaking, and some solution rely on implementation details, it could be a matter of tracking the clients yourself:

var clients = [];

io.sockets.on('connect', function(client) {
    clients.push(client); 

    client.on('disconnect', function() {
        clients.splice(clients.indexOf(client), 1);
    });
});

Using ADB to capture the screen

To start recording your device’s screen, run the following command:

adb shell screenrecord /sdcard/example.mp4

This command will start recording your device’s screen using the default settings and save the resulting video to a file at /sdcard/example.mp4 file on your device.

When you’re done recording, press Ctrl+C in the Command Prompt window to stop the screen recording. You can then find the screen recording file at the location you specified. Note that the screen recording is saved to your device’s internal storage, not to your computer.

The default settings are to use your device’s standard screen resolution, encode the video at a bitrate of 4Mbps, and set the maximum screen recording time to 180 seconds. For more information about the command-line options you can use, run the following command:

adb shell screenrecord --help

This works without rooting the device. Hope this helps.

Export query result to .csv file in SQL Server 2008

Yes, all these are possible when you have the direct access to the servers. But what if you have only access to the server from a web / application server? Well, the situation was this with us a long back and the solution was SQL Server Export to CSV.

How do I use InputFilter to limit characters in an EditText in Android?

First add into strings.xml:

<string name="vin_code_mask">0123456789abcdefghjklmnprstuvwxyz</string>

XML:

android:digits="@string/vin_code_mask"

Code in Kotlin:

edit_text.filters += InputFilter { source, start, end, _, _, _ ->
    val mask = getString(R.string.vin_code_mask)
    for (i in start until end) {
        if (!mask.contains(source[i])) {
            return@InputFilter ""
        }
    }
    null
}

Strange, but it works weirdly on emulator's soft keyboard.

Warning! The following code will filter all letters and other symbols except digits for software keyboards. Only digital keyboard will appear on smartphones.

edit_text.keyListener = DigitsKeyListener.getInstance(context.getString(R.string.vin_code_mask))

I also usually set maxLength, filters, inputType.

How to grep for two words existing on the same line?

git grep

Here is the syntax using git grep combining multiple patterns using Boolean expressions:

git grep -e pattern1 --and -e pattern2 --and -e pattern3

The above command will print lines matching all the patterns at once.

If the files aren't under version control, add --no-index param.

Search files in the current directory that is not managed by Git.

Check man git-grep for help.

See also:

Domain Account keeping locking out with correct password every few minutes

Try this solution from http://social.technet.microsoft.com/Forums/en/w7itprosecurity/thread/e1ef04fa-6aea-47fe-9392-45929239bd68

Microsoft Support found the problem for us. Our domain accounts were locking when a Windows 7 computer was started. The Windows 7 computer had a hidden old password from that domain account. There are passwords that can be stored in the SYSTEM context that can't be seen in the normal Credential Manager view.

Download PsExec.exe from http://technet.microsoft.com/en-us/sysinternals/bb897553.aspx and copy it to C:\Windows\System32.

From a command prompt run: psexec -i -s -d cmd.exe

From the new DOS window run: rundll32 keymgr.dll,KRShowKeyMgr

Remove any items that appear in the list of Stored User Names and Passwords. Restart the computer.

array_push() with key value pair

So what about having:

$data['cat']='wagon';

What is the difference between SAX and DOM?

Both SAX and DOM are used to parse the XML document. Both has advantages and disadvantages and can be used in our programming depending on the situation

SAX:

  1. Parses node by node

  2. Does not store the XML in memory

  3. We cant insert or delete a node

  4. Top to bottom traversing

DOM

  1. Stores the entire XML document into memory before processing

  2. Occupies more memory

  3. We can insert or delete nodes

  4. Traverse in any direction.

If we need to find a node and does not need to insert or delete we can go with SAX itself otherwise DOM provided we have more memory.

Bootstrap 3 modal responsive

From the docs:

Modals have two optional sizes, available via modifier classes to be placed on a .modal-dialog: modal-lg and modal-sm (as of 3.1).

Also the modal dialogue will scale itself on small screens (as of 3.1.1).

Usage of MySQL's "IF EXISTS"

The accepted answer works well and one can also just use the 

If Exists (...) Then ... End If;

syntax in Mysql procedures (if acceptable for circumstance) and it will behave as desired/expected. Here's a link to a more thorough source/description: https://dba.stackexchange.com/questions/99120/if-exists-then-update-else-insert

One problem with the solution by @SnowyR is that it does not really behave like "If Exists" in that the (Select 1 = 1 ...) subquery could return more than one row in some circumstances and so it gives an error. I don't have permissions to respond to that answer directly so I thought I'd mention it here in case it saves someone else the trouble I experienced and so others might know that it is not an equivalent solution to MSSQLServer "if exists"!

add string to String array

As many of the answer suggesting better solution is to use ArrayList. ArrayList size is not fixed and it is easily manageable.

It is resizable-array implementation of the List interface. Implements all optional list operations, and permits all elements, including null. In addition to implementing the List interface, this class provides methods to manipulate the size of the array that is used internally to store the list.

Each ArrayList instance has a capacity. The capacity is the size of the array used to store the elements in the list. It is always at least as large as the list size. As elements are added to an ArrayList, its capacity grows automatically.

Note that this implementation is not synchronized.

ArrayList<String> scripts = new ArrayList<String>();
scripts.add("test1");
scripts.add("test2");
scripts.add("test3");

How to use _CRT_SECURE_NO_WARNINGS

Add by

Configuration Properties>>C/C++>>Preporocessor>>Preprocessor Definitions>> _CRT_SECURE_NO_WARNINGS

screenshot of the relevant config interface

How to go from one page to another page using javascript?

To simply redirect a browser using javascript:

window.location.href = "http://example.com/new_url";

To redirect AND submit a form (i.e. login details), requires no javascript:

<form action="/new_url" method="POST">
   <input name="username">
   <input type="password" name="password">
   <button type="submit">Submit</button>
</form>

How to scroll to bottom in react?

I created a empty element in the end of messages, and scrolled to that element. No need of keeping track of refs.

How to show PIL Image in ipython notebook

case python3

from PIL import Image
from IPython.display import HTML
from io import BytesIO
from base64 import b64encode

pil_im = Image.open('data/empire.jpg')
b = BytesIO()  
pil_im.save(b, format='png')
HTML("<img src='data:image/png;base64,{0}'/>".format(b64encode(b.getvalue()).decode('utf-8')))

R Apply() function on specific dataframe columns

As mentioned, you simply want the standard R apply function applied to columns (MARGIN=2):

wifi[,4:9] <- apply(wifi[,4:9], MARGIN=2, FUN=A)

Or, for short:

wifi[,4:9] <- apply(wifi[,4:9], 2, A)

This updates columns 4:9 in-place using the A() function. Now, let's assume that na.rm is an argument to A(), which it probably should be. We can pass na.rm=T to remove NA values from the computation like so:

wifi[,4:9] <- apply(wifi[,4:9], MARGIN=2, FUN=A, na.rm=T)

The same is true for any other arguments you want to pass to your custom function.

How to install mscomct2.ocx file from .cab file (Excel User Form and VBA)

You're correct that this is really painful to hand out to others, but if you have to, this is how you do it.

  1. Just extract the .ocx file from the .cab file (it is similar to a zip)
  2. Copy to the system folder (c:\windows\sysWOW64 for 64 bit systems and c:\windows\system32 for 32 bit)
  3. Use regsvr32 through the command prompt to register the file (e.g. "regsvr32 c:\windows\sysWOW64\mscomct2.ocx")

References

Locate current file in IntelliJ

In addition to the other options, in at least IntelliJ IDEA 2017 Ultimate, WebStorm 2020.2, and probably a ton of other versions, you can do it in a single shortcut.

Edit preferences, search for Select in Project View, and under Keymap, view the mapped shortcut or map one of your choice.

On the Mac, Ctrl + Option + L is not already used, and is the same shortcut as Visual Studio for Windows uses natively (Ctrl + Alt + L, so that could be a good choice.

figure of imshow() is too small

That's strange, it definitely works for me:

from matplotlib import pyplot as plt

plt.figure(figsize = (20,2))
plt.imshow(random.rand(8, 90), interpolation='nearest')

I am using the "MacOSX" backend, btw.

How do I discover memory usage of my application in Android?

This is a work in progress, but this is what I don't understand:

ActivityManager activityManager = (ActivityManager) context.getSystemService(ACTIVITY_SERVICE);
MemoryInfo memoryInfo = new ActivityManager.MemoryInfo();
activityManager.getMemoryInfo(memoryInfo);

Log.i(TAG, " memoryInfo.availMem " + memoryInfo.availMem + "\n" );
Log.i(TAG, " memoryInfo.lowMemory " + memoryInfo.lowMemory + "\n" );
Log.i(TAG, " memoryInfo.threshold " + memoryInfo.threshold + "\n" );

List<RunningAppProcessInfo> runningAppProcesses = activityManager.getRunningAppProcesses();

Map<Integer, String> pidMap = new TreeMap<Integer, String>();
for (RunningAppProcessInfo runningAppProcessInfo : runningAppProcesses)
{
    pidMap.put(runningAppProcessInfo.pid, runningAppProcessInfo.processName);
}

Collection<Integer> keys = pidMap.keySet();

for(int key : keys)
{
    int pids[] = new int[1];
    pids[0] = key;
    android.os.Debug.MemoryInfo[] memoryInfoArray = activityManager.getProcessMemoryInfo(pids);
    for(android.os.Debug.MemoryInfo pidMemoryInfo: memoryInfoArray)
    {
        Log.i(TAG, String.format("** MEMINFO in pid %d [%s] **\n",pids[0],pidMap.get(pids[0])));
        Log.i(TAG, " pidMemoryInfo.getTotalPrivateDirty(): " + pidMemoryInfo.getTotalPrivateDirty() + "\n");
        Log.i(TAG, " pidMemoryInfo.getTotalPss(): " + pidMemoryInfo.getTotalPss() + "\n");
        Log.i(TAG, " pidMemoryInfo.getTotalSharedDirty(): " + pidMemoryInfo.getTotalSharedDirty() + "\n");
    }
}

Why isn't the PID mapped to the result in activityManager.getProcessMemoryInfo()? Clearly you want to make the resulting data meaningful, so why has Google made it so difficult to correlate the results? The current system doesn't even work well if I want to process the entire memory usage since the returned result is an array of android.os.Debug.MemoryInfo objects, but none of those objects actually tell you what pids they are associated with. If you simply pass in an array of all pids, you will have no way to understand the results. As I understand it's use, it makes it meaningless to pass in more than one pid at a time, and then if that's the case, why make it so that activityManager.getProcessMemoryInfo() only takes an int array?

Python, compute list difference

 
A = [1,2,3,4]
B = [2,5]

#A - B
x = list(set(A) - set(B))
#B - A 
y = list(set(B) - set(A))

print x
print y

Is it worth using Python's re.compile?

As an alternative answer, as I see that it hasn't been mentioned before, I'll go ahead and quote the Python 3 docs:

Should you use these module-level functions, or should you get the pattern and call its methods yourself? If you’re accessing a regex within a loop, pre-compiling it will save a few function calls. Outside of loops, there’s not much difference thanks to the internal cache.

How to escape comma and double quote at same time for CSV file?

Excel has to be able to handle the exact same situation.

Put those things into Excel, save them as CSV, and examine the file with a text editor. Then you'll know the rules Excel is applying to these situations.

Make Java produce the same output.

The formats used by Excel are published, by the way...

****Edit 1:**** Here's what Excel does
****Edit 2:**** Note that php's fputcsv does the same exact thing as excel if you use " as the enclosure. 

[email protected]
Richard
"This is what I think"

gets transformed into this:

Email,Fname,Quoted  
[email protected],Richard,"""This is what I think"""

Loading DLLs at runtime in C#

Members must be resolvable at compile time to be called directly from C#. Otherwise you must use reflection or dynamic objects.

Reflection

namespace ConsoleApplication1
{
    using System;
    using System.Reflection;

    class Program
    {
        static void Main(string[] args)
        {
            var DLL = Assembly.LoadFile(@"C:\visual studio 2012\Projects\ConsoleApplication1\ConsoleApplication1\DLL.dll");

            foreach(Type type in DLL.GetExportedTypes())
            {
                var c = Activator.CreateInstance(type);
                type.InvokeMember("Output", BindingFlags.InvokeMethod, null, c, new object[] {@"Hello"});
            }

            Console.ReadLine();
        }
    }
}

Dynamic (.NET 4.0)

namespace ConsoleApplication1
{
    using System;
    using System.Reflection;

    class Program
    {
        static void Main(string[] args)
        {
            var DLL = Assembly.LoadFile(@"C:\visual studio 2012\Projects\ConsoleApplication1\ConsoleApplication1\DLL.dll");

            foreach(Type type in DLL.GetExportedTypes())
            {
                dynamic c = Activator.CreateInstance(type);
                c.Output(@"Hello");
            }

            Console.ReadLine();
        }
    }
}

What's the complete range for Chinese characters in Unicode?

To summarize, it sounds like these are them:

var blocks = [
  [0x3400, 0x4DB5],
  [0x4E00, 0x62FF],
  [0x6300, 0x77FF],
  [0x7800, 0x8CFF],
  [0x8D00, 0x9FCC],
  [0x2e80, 0x2fd5],
  [0x3190, 0x319f],
  [0x3400, 0x4DBF],
  [0x4E00, 0x9FCC],
  [0xF900, 0xFAAD],
  [0x20000, 0x215FF],
  [0x21600, 0x230FF],
  [0x23100, 0x245FF],
  [0x24600, 0x260FF],
  [0x26100, 0x275FF],
  [0x27600, 0x290FF],
  [0x29100, 0x2A6DF],
  [0x2A700, 0x2B734],
  [0x2B740, 0x2B81D]
]

How does Python's super() work with multiple inheritance?

Maybe there's still something that can be added, a small example with Django rest_framework, and decorators. This provides an answer to the implicit question: "why would I want this anyway?"

As said: we're with Django rest_framework, and we're using generic views, and for each type of objects in our database we find ourselves with one view class providing GET and POST for lists of objects, and an other view class providing GET, PUT, and DELETE for individual objects.

Now the POST, PUT, and DELETE we want to decorate with Django's login_required. Notice how this touches both classes, but not all methods in either class.

A solution could go through multiple inheritance.

from django.utils.decorators import method_decorator
from django.contrib.auth.decorators import login_required

class LoginToPost:
    @method_decorator(login_required)
    def post(self, arg, *args, **kwargs):
        super().post(arg, *args, **kwargs)

Likewise for the other methods.

In the inheritance list of my concrete classes, I would add my LoginToPost before ListCreateAPIView and LoginToPutOrDelete before RetrieveUpdateDestroyAPIView. My concrete classes' get would stay undecorated.

if (boolean == false) vs. if (!boolean)

- Here its more about the coding style than being the functionality....

- The 1st option is very clear, but then the 2nd one is quite elegant... no offense, its just my view..

How do I create batch file to rename large number of files in a folder?

You don't need a batch file, just do this from powershell :

powershell -C "gci | % {rni $_.Name ($_.Name -replace 'Vacation2010', 'December')}"

VideoView Full screen in android application

Set full screen this way,

DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
android.widget.LinearLayout.LayoutParams params = (android.widget.LinearLayout.LayoutParams) videoView.getLayoutParams();
params.width = metrics.widthPixels;
params.height = metrics.heightPixels;
params.leftMargin = 0;
videoView.setLayoutParams(params);

And back to original size, this way.

DisplayMetrics metrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
android.widget.LinearLayout.LayoutParams params = (android.widget.LinearLayout.LayoutParams) videoView.getLayoutParams();
params.width = (int)(300*metrics.density);
params.height = (int)(250*metrics.density);
params.leftMargin = 30;
videoView.setLayoutParams(params);

How do I count the number of rows and columns in a file using bash?

 
head -1 file.tsv |head -1 train.tsv |tr '\t' '\n' |wc -l

take the first line, change tabs (or you can use ',' instead of '\t' for commas), count the number of lines.

Twitter bootstrap modal-backdrop doesn't disappear

Using toggle instead of hide, solved my problem

Is it better to use NOT or <> when comparing values?

The latter (<>), because the meaning of the former isn't clear unless you have a perfect understanding of the order of operations as it applies to the Not and = operators: a subtlety which is easy to miss.

Multiple Buttons' OnClickListener() android

Set a Tag on each button to whatever you want to work with, in this case probably an Integer. Then you need only one OnClickListener for all of your buttons:

Button one = (Button) findViewById(R.id.oneButton);
Button two = (Button) findViewById(R.id.twoButton);
one.setTag(new Integer(1));
two.setTag(new Integer(2));

OnClickListener onClickListener = new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        TextView output = (TextView) findViewById(R.id.output);
        output.append(v.getTag());
    }
}

one.setOnClickListener(onClickListener);
two.setOnClickListener(onClickListener);

Looping over a list in Python

Do this instead:

values = [[1,2,3],[4,5]]
for x in values:
    if len(x) == 3:
       print(x)

Wait some seconds without blocking UI execution

I think what you are after is Task.Delay. This doesn't block the thread like Sleep does and it means you can do this using a single thread using the async programming model.

async Task PutTaskDelay()
{
    await Task.Delay(5000);
} 

private async void btnTaskDelay_Click(object sender, EventArgs e)
{
    await PutTaskDelay();
    MessageBox.Show("I am back");
}

Angular 2 / 4 / 5 not working in IE11

If you have still problems that not all JavaScript functions are working add this line in your polyfills. It fixes the missing ‘values’ method: 

import 'core-js/es7/object';

And this line fixes the missing ‘includes’ method:

import 'core-js/es7/array'

SQL Query for Student mark functionality

Using a Subquery:

select m.subid, m.stid, m.mark
from marks m,
    (select m2.subid, max(m2.mark) max_mark
    from marks m2
    group by subid) subq

where subq.subid = m.subid
and subq.max_mark = m.mark
order by 1,2;

Using Rank with Partition:

select subid, stid, mark
from (select m.subid, m.stid, m.mark,
rank() over (partition by m.subid order by m.mark desc) Mark_Rank
from marks m)
where Mark_Rank = 1
order by 1,2;

ASP.NET MVC: What is the correct way to redirect to pages/actions in MVC?

 
RedirectToAction("actionName", "controllerName");

It has other overloads as well, please check up!

Also, If you are new and you are not using T4MVC, then I would recommend you to use it!

It gives you intellisence for actions,Controllers,views etc (no more magic strings)

How to start up spring-boot application via command line?

A Spring Boot project configured through Maven can be run using the following command from the project source folder

mvn spring-boot:run

Sending email with PHP from an SMTP server

Here is a way to do it with PHP PEAR

// Pear Mail Library
require_once "Mail.php";

$from = '<[email protected]>'; //change this to your email address
$to = '<[email protected]>'; // change to address
$subject = 'Insert subject here'; // subject of mail
$body = "Hello world! this is the content of the email"; //content of mail

$headers = array(
    'From' => $from,
    'To' => $to,
    'Subject' => $subject
);

$smtp = Mail::factory('smtp', array(
        'host' => 'ssl://smtp.gmail.com',
        'port' => '465',
        'auth' => true,
        'username' => '[email protected]', //your gmail account
        'password' => 'snip' // your password
    ));

// Send the mail
$mail = $smtp->send($to, $headers, $body);

//check mail sent or not
if (PEAR::isError($mail)) {
    echo '<p>'.$mail->getMessage().'</p>';
} else {
    echo '<p>Message successfully sent!</p>';
}

If you use Gmail SMTP remember to enable SMTP in your Gmail account, under settings

EDIT: If you can't find Mail.php on debian/ubuntu you can install php-pear with

sudo apt install php-pear

Then install the mail extention:

sudo pear install mail
sudo pear install Net_SMTP
sudo pear install Auth_SASL
sudo pear install mail_mime

Then you should be able to load it by simply require_once "Mail.php" else it is located here: /usr/share/php/Mail.php

Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine

I've the same message, I have a webpage with do on visual studio 2010, I read a file.xls on that page,in my project visual has not any problem, when I put it on my IIS local throw me a 'Microsoft.Jet.OLEDB.4.0' provider is not registered on the local machine' ,I fixed that problem next following this steps,

1.-Open IIS
2.-Change the appPool on Advanced Settings
3.-true to enable to 32-bit application.

and that's all

ps.I changed Configuration Manager to X86 on Active Solution Platform

jQuery.ajax returns 400 Bad Request

I was getting the 400 Bad Request error, even after setting:

contentType: "application/json",
dataType: "json"

The issue was with the type of a property passed in the json object, for the data property in the ajax request object.
To figure out the issue, I added an error handler and then logged the error to the console. Console log will clearly show validation errors for the properties if any.

This was my initial code:

var data = {
    "TestId": testId,
    "PlayerId": parseInt(playerId),
    "Result": result
};

var url = document.location.protocol + "//" + document.location.host + "/api/tests"
$.ajax({
    url: url,
    method: "POST",
    contentType: "application/json",
    data: JSON.stringify(data), // issue with a property type in the data object
    dataType: "json",
    error: function (e) {
        console.log(e); // logging the error object to console
    },
    success: function () {
        console.log('Success saving test result');
    }
});

Now after making the request, I checked the console tab in the browser development tool.
It looked like this: enter image description here

responseJSON.errors[0] clearly shows a validation error: The JSON value could not be converted to System.String. Path: $.TestId, which means I have to convert TestId to a string in the data object, before making the request.

Changing the data object creation like below fixed the issue for me:

var data = {
        "TestId": String(testId), //converting testId to a string
        "PlayerId": parseInt(playerId),
        "Result": result
};

I assume other possible errors could also be identified by logging and inspecting the error object.

Confusion: @NotNull vs. @Column(nullable = false) with JPA and Hibernate

The JPA @Column Annotation

The nullable attribute of the @Column annotation has two purposes:

  • it's used by the schema generation tool
  • it's used by Hibernate during flushing the Persistence Context

Schema Generation Tool

The HBM2DDL schema generation tool translates the @Column(nullable = false) entity attribute to a NOT NULL constraint for the associated table column when generating the CREATE TABLE statement.

As I explained in the Hibernate User Guide, it's better to use a tool like Flyway instead of relying on the HBM2DDL mechanism for generating the database schema.

Persistence Context Flush

When flushing the Persistence Context, Hibernate ORM also uses the @Column(nullable = false) entity attribute:

new Nullability( session ).checkNullability( values, persister, true );

If the validation fails, Hibernate will throw a PropertyValueException, and prevents the INSERT or UPDATE statement to be executed needesly:

if ( !nullability[i] && value == null ) {
    //check basic level one nullablilty
    throw new PropertyValueException(
            "not-null property references a null or transient value",
            persister.getEntityName(),
            persister.getPropertyNames()[i]
        );    
}

The Bean Validation @NotNull Annotation

The @NotNull annotation is defined by Bean Validation and, just like Hibernate ORM is the most popular JPA implementation, the most popular Bean Validation implementation is the Hibernate Validator framework.

When using Hibernate Validator along with Hibernate ORM, Hibernate Validator will throw a ConstraintViolation when validating the entity.

Simple way to sort strings in the (case sensitive) alphabetical order

I recently answered a similar question here. Applying the same approach to your problem would yield following solution:

list.sort(
  p2Ord(stringOrd, stringOrd).comap(new F<String, P2<String, String>>() {
    public P2<String, String> f(String s) {
      return p(s.toLowerCase(), s);
    }
  })
);

Jquery open popup on button click for bootstrap

Below mentioned link gives the clear explanation with example.

http://www.aspsnippets.com/Articles/Open-Show-jQuery-UI-Dialog-Modal-Popup-on-Button-Click.aspx

Code from the same link

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script src="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/jquery-ui.js" type="text/javascript"></script>
<link href="http://ajax.aspnetcdn.com/ajax/jquery.ui/1.8.9/themes/blitzer/jquery-ui.css"
    rel="stylesheet" type="text/css" />
<script type="text/javascript">
    $(function () {
        $("#dialog").dialog({
            modal: true,
            autoOpen: false,
            title: "jQuery Dialog",
            width: 300,
            height: 150
        });
        $("#btnShow").click(function () {
            $('#dialog').dialog('open');
        });
    });
</script>
<input type="button" id="btnShow" value="Show Popup" />
<div id="dialog" style="display: none" align = "center">
    This is a jQuery Dialog.
</div>

Possible to perform cross-database queries with PostgreSQL?

If performance is important and most queries are read-only, I would suggest to replicate data over to another database. While this seems like unneeded duplication of data, it might help if indexes are required.

This can be done with simple on insert triggers which in turn call dblink to update another copy. There are also full-blown replication options (like Slony) but that's off-topic.

Importing class/java files in Eclipse

import class folder does not work for me, but add jar worked!

1. put the class folder under the project folder

2. Zip the class folder

3. Highlight project name, click "Project" in the top toolbar, click "Properties", click "Libraries" tab, click "Add External jars".

4. Add the zip file. Done!

Pure JavaScript Send POST Data Without a Form

You can use the XMLHttpRequest object as follows:

xhr.open("POST", url, true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
xhr.send(someStuff);

That code would post someStuff to url. Just make sure that when you create your XMLHttpRequest object, it will be cross-browser compatible. There are endless examples out there of how to do that.

What's the difference between utf8_general_ci and utf8_unicode_ci?

For those people still arriving at this question in 2020 or later, there are newer options that may be better than both of these. For example, utf8mb4_0900_ai_ci.

All these collations are for the UTF-8 character encoding. The differences are in how text is sorted and compared.

_unicode_ci and _general_ci are two different sets of rules for sorting and comparing text according to the way we expect. Newer versions of MySQL introduce new sets of rules, too, such as _0900_ai_ci for equivalent rules based on Unicode 9.0 - and with no equivalent _general_ci variant. People reading this now should probably use one of these newer collations instead of either _unicode_ci or _general_ci. The description of those older collations below is provided for interest only.

MySQL is currently transitioning away from an older, flawed UTF-8 implementation. For now, you need to use utf8mb4 instead of utf8 for the character encoding part, to ensure you are getting the fixed version. The flawed version remains for backward compatibility, though it is being deprecated.

Key differences

  • utf8mb4_unicode_ci is based on the official Unicode rules for universal sorting and comparison, which sorts accurately in a wide range of languages.

  • utf8mb4_general_ci is a simplified set of sorting rules which aims to do as well as it can while taking many short-cuts designed to improve speed. It does not follow the Unicode rules and will result in undesirable sorting or comparison in some situations, such as when using particular languages or characters.

    On modern servers, this performance boost will be all but negligible. It was devised in a time when servers had a tiny fraction of the CPU performance of today's computers.

Benefits of utf8mb4_unicode_ci over utf8mb4_general_ci

utf8mb4_unicode_ci, which uses the Unicode rules for sorting and comparison, employs a fairly complex algorithm for correct sorting in a wide range of languages and when using a wide range of special characters. These rules need to take into account language-specific conventions; not everybody sorts their characters in what we would call 'alphabetical order'.

As far as Latin (ie "European") languages go, there is not much difference between the Unicode sorting and the simplified utf8mb4_general_ci sorting in MySQL, but there are still a few differences:

  • For examples, the Unicode collation sorts "ß" like "ss", and "Œ" like "OE" as people using those characters would normally want, whereas utf8mb4_general_ci sorts them as single characters (presumably like "s" and "e" respectively).

  • Some Unicode characters are defined as ignorable, which means they shouldn't count toward the sort order and the comparison should move on to the next character instead. utf8mb4_unicode_ci handles these properly.

In non-latin languages, such as Asian languages or languages with different alphabets, there may be a lot more differences between Unicode sorting and the simplified utf8mb4_general_ci sorting. The suitability of utf8mb4_general_ci will depend heavily on the language used. For some languages, it'll be quite inadequate.

What should you use?

There is almost certainly no reason to use utf8mb4_general_ci anymore, as we have left behind the point where CPU speed is low enough that the performance difference would be important. Your database will almost certainly be limited by other bottlenecks than this.

In the past, some people recommended to use utf8mb4_general_ci except when accurate sorting was going to be important enough to justify the performance cost. Today, that performance cost has all but disappeared, and developers are treating internationalization more seriously.

There's an argument to be made that if speed is more important to you than accuracy, you may as well not do any sorting at all. It's trivial to make an algorithm faster if you do not need it to be accurate. So, utf8mb4_general_ci is a compromise that's probably not needed for speed reasons and probably also not suitable for accuracy reasons.

One other thing I'll add is that even if you know your application only supports the English language, it may still need to deal with people's names, which can often contain characters used in other languages in which it is just as important to sort correctly. Using the Unicode rules for everything helps add peace of mind that the very smart Unicode people have worked very hard to make sorting work properly.

What the parts mean

Firstly, ci is for case-insensitive sorting and comparison. This means it's suitable for textual data, and case is not important. The other types of collation are cs (case-sensitive) for textual data where case is important, and bin, for where the encoding needs to match, bit for bit, which is suitable for fields which are really encoded binary data (including, for example, Base64). Case-sensitive sorting leads to some weird results and case-sensitive comparison can result in duplicate values differing only in letter case, so case-sensitive collations are falling out of favor for textual data - if case is significant to you, then otherwise ignorable punctuation and so on is probably also significant, and a binary collation might be more appropriate.

Next, unicode or general refers to the specific sorting and comparison rules - in particular, the way text is normalized or compared. There are many different sets of rules for the utf8mb4 character encoding, with unicode and general being two that attempt to work well in all possible languages rather than one specific one. The differences between these two sets of rules are the subject of this answer. Note that unicode uses rules from Unicode 4.0. Recent versions of MySQL add the rulesets unicode_520 using rules from Unicode 5.2, and 0900 (dropping the "unicode_" part) using rules from Unicode 9.0.

And lastly, utf8mb4 is of course the character encoding used internally. In this answer I'm talking only about Unicode based encodings.

Convert Java string to Time, NOT Date

You might consider Joda Time or Java 8, which has a type called LocalTime specifically for a time of day without a date component.

Example code in Joda-Time 2.7/Java 8.

LocalTime t = LocalTime.parse( "17:40" ) ;

Source file not compiled Dev C++

I found a solution. Please follow the following steps:

  1. Right Click the My comp. Icon

  2. Click Advanced Setting.

  3. CLick Environment Variable. On the top part of Environment Variable Click New

  4. Set Variable name as: PATH then Set Variable Value as: (" the location of g++ .exe" ) For ex. C:\Program Files (x86)\Dev-Cpp\MinGW64\bin

  5. Click OK

Opacity of div's background without affecting contained element in IE 8?

opacity on parent element sets it for the whole sub DOM tree

You can't really set opacity for certain element that wouldn't cascade to descendants as well. That's not how CSS opacity works I'm afraid.

What you can do is to have two sibling elements in one container and set transparent one's positioning:

<div id="container">
    <div id="transparent"></div>
    <div id="content"></div>
</div>

then you have to set transparent position: absolute/relative so its content sibling will be rendered over it.

rgba can do background transparency of coloured backgrounds

rgba colour setting on element's background-color will of course work, but it will limit you to only use colour as background. No images I'm afraid. You can of course use CSS3 gradients though if you provide gradient stop colours in rgba. That works as well.

But be advised that rgba may not be supported by your required browsers.

Alert-free modal dialog functionality

But if you're after some kind of masking the whole page, this is usually done by adding a separate div with this set of styles:

position: fixed;
width: 100%;
height: 100%;
z-index: 1000; /* some high enough value so it will render on top */
opacity: .5;
filter: alpha(opacity=50);

Then when you display the content it should have a higher z-index. But these two elements are not related in terms of siblings or anything. They're just displayed as they should be. One over the other.

Passing variables through handlebars partial

Sounds like you want to do something like this:

{{> person {another: 'attribute'} }}

Yehuda already gave you a way of doing that:

{{> person this}}

But to clarify:

To give your partial its own data, just give it its own model inside the existing model, like so:

{{> person this.childContext}}

In other words, if this is the model you're giving to your template: 

var model = {
    some : 'attribute'
}

Then add a new object to be given to the partial:

var model = {
    some : 'attribute',
    childContext : {
        'another' : 'attribute' // this goes to the child partial
    }
}

childContext becomes the context of the partial like Yehuda said -- in that, it only sees the field another, but it doesn't see (or care about the field some). If you had id in the top level model, and repeat id again in the childContext, that'll work just fine as the partial only sees what's inside childContext.

Editing in the Chrome debugger

As this is quite popular question that deals with live-editing of JS, I want to point out another useful option. As described by svjacob in his answer:

I realized I could attach a break-point in the debugger to some line of code before what I wanted to dynamically edit. And since break-points stay even after a reload of the page, I was able to edit the changes I wanted while paused at break-point and then continued to let the page load.

The above solution didn't work for me for quite large JS (webpack bundle - 3.21MB minified version, 130k lines of code in prettified version) - chrome crashed and asked for page reloading which reverted any saved changes. The way to go in this case was Fiddler where you can set AutoRespond option to replace any remote resource with any local file from your computer - see this SO question for details.

In my case I also had to add CORS headers to fiddler to successfully mock response.

Are strongly-typed functions as parameters possible in TypeScript?

Besides what other said, a common problem is to declare the types of the same function that is overloaded. Typical case is EventEmitter on() method which will accept multiple kind of listeners. Similar could happen When working with redux actions - and there you use the action type as literal to mark the overloading, In case of EventEmitters, you use the event name literal type:

interface MyEmitter extends EventEmitter {
  on(name:'click', l: ClickListener):void
  on(name:'move', l: MoveListener):void
  on(name:'die', l: DieListener):void
  //and a generic one
  on(name:string, l:(...a:any[])=>any):void
}

type ClickListener = (e:ClickEvent)=>void
type MoveListener = (e:MoveEvent)=>void
... etc

// will type check the correct listener when writing something like:
myEmitter.on('click', e=>...<--- autocompletion

How to execute an Oracle stored procedure via a database link

check http://www.tech-archive.net/Archive/VB/microsoft.public.vb.database.ado/2005-08/msg00056.html

one needs to use something like 

cmd.CommandText = "BEGIN foo@v; END;"

worked for me in vb.net, c#

jQuery datepicker, onSelect won't work

It should be "datepicker", not "datePicker" if you are using the jQuery UI DatePicker plugin. Perhaps, you have a different but similar plugin that doesn't support the select handler.

Bootstrap row class contains margin-left and margin-right which creates problems

I used div class="form-control" instead of div class="row"

That fixed for me.

AttributeError: Can only use .dt accessor with datetimelike values

Your problem here is that to_datetime silently failed so the dtype remained as str/object, if you set param errors='coerce' then if the conversion fails for any particular string then those rows are set to NaT.

df['Date'] = pd.to_datetime(df['Date'], errors='coerce')

So you need to find out what is wrong with those specific row values.

See the docs

How to select top n rows from a datatable/dataview in ASP.NET

 
myDataTable.AsEnumerable().Take(5).CopyToDataTable()

Append an array to another array in JavaScript

If you want to modify the original array instead of returning a new array, use .push()...

array1.push.apply(array1, array2);
array1.push.apply(array1, array3);

I used .apply to push the individual members of arrays 2 and 3 at once.

or...

array1.push.apply(array1, array2.concat(array3));

To deal with large arrays, you can do this in batches.

for (var n = 0, to_add = array2.concat(array3); n < to_add.length; n+=300) {
    array1.push.apply(array1, to_add.slice(n, n+300));
}

If you do this a lot, create a method or function to handle it.

var push_apply = Function.apply.bind([].push);
var slice_call = Function.call.bind([].slice);

Object.defineProperty(Array.prototype, "pushArrayMembers", {
    value: function() {
        for (var i = 0; i < arguments.length; i++) {
            var to_add = arguments[i];
            for (var n = 0; n < to_add.length; n+=300) {
                push_apply(this, slice_call(to_add, n, n+300));
            }
        }
    }
});

and use it like this:

array1.pushArrayMembers(array2, array3);

_x000D_
_x000D_ 
var push_apply = Function.apply.bind([].push);_x000D_
var slice_call = Function.call.bind([].slice);_x000D_
_x000D_
Object.defineProperty(Array.prototype, "pushArrayMembers", {_x000D_
    value: function() {_x000D_
        for (var i = 0; i < arguments.length; i++) {_x000D_
            var to_add = arguments[i];_x000D_
            for (var n = 0; n < to_add.length; n+=300) {_x000D_
                push_apply(this, slice_call(to_add, n, n+300));_x000D_
            }_x000D_
        }_x000D_
    }_x000D_
});_x000D_
_x000D_
var array1 = ['a','b','c'];_x000D_
var array2 = ['d','e','f'];_x000D_
var array3 = ['g','h','i'];_x000D_
_x000D_
array1.pushArrayMembers(array2, array3);_x000D_
_x000D_
document.body.textContent = JSON.stringify(array1, null, 4);
_x000D_
_x000D_
_x000D_

How to insert values in table with foreign key using MySQL?

Case 1: Insert Row and Query Foreign Key

Here is an alternate syntax I use:

INSERT INTO tab_student 
   SET name_student = 'Bobby Tables',
       id_teacher_fk = (
       SELECT id_teacher
         FROM tab_teacher
        WHERE name_teacher = 'Dr. Smith')

I'm doing this in Excel to import a pivot table to a dimension table and a fact table in SQL so you can import to both department and expenses tables from the following:

enter image description here

Case 2: Insert Row and Then Insert Dependant Row

Luckily, MySQL supports LAST_INSERT_ID() exactly for this purpose.

INSERT INTO tab_teacher
   SET name_teacher = 'Dr. Smith';
INSERT INTO tab_student 
   SET name_student = 'Bobby Tables',
       id_teacher_fk = LAST_INSERT_ID()

Strip all non-numeric characters from string in JavaScript

Use the string's .replace method with a regex of \D, which is a shorthand character class that matches all non-digits:

myString = myString.replace(/\D/g,'');

Calling stored procedure from another stored procedure SQL Server

You could add an OUTPUT parameter to test2, and set it to the new id straight after the INSERT using:

SELECT @NewIdOutputParam = SCOPE_IDENTITY()

Then in test1, retrieve it like so:

DECLARE @NewId INTEGER
EXECUTE test2 @NewId OUTPUT
-- Now use @NewId as needed

Utilizing multi core for tar+gzip/bzip compression/decompression

You can use pigz instead of gzip, which does gzip compression on multiple cores. Instead of using the -z option, you would pipe it through pigz:

tar cf - paths-to-archive | pigz > archive.tar.gz

By default, pigz uses the number of available cores, or eight if it could not query that. You can ask for more with -p n, e.g. -p 32. pigz has the same options as gzip, so you can request better compression with -9. E.g.

tar cf - paths-to-archive | pigz -9 -p 32 > archive.tar.gz

SQL/mysql - Select distinct/UNIQUE but return all columns?

Try

SELECT table.* FROM table 
WHERE otherField = 'otherValue'
GROUP BY table.fieldWantedToBeDistinct
limit x

How to convert string to datetime format in pandas python?

Use to_datetime, there is no need for a format string the parser is man/woman enough to handle it:

In [51]:
pd.to_datetime(df['I_DATE'])

Out[51]:
0   2012-03-28 14:15:00
1   2012-03-28 14:17:28
2   2012-03-28 14:50:50
Name: I_DATE, dtype: datetime64[ns]

To access the date/day/time component use the dt accessor:

In [54]:
df['I_DATE'].dt.date

Out[54]:
0    2012-03-28
1    2012-03-28
2    2012-03-28
dtype: object

In [56]:    
df['I_DATE'].dt.time

Out[56]:
0    14:15:00
1    14:17:28
2    14:50:50
dtype: object

You can use strings to filter as an example:

In [59]:
df = pd.DataFrame({'date':pd.date_range(start = dt.datetime(2015,1,1), end = dt.datetime.now())})
df[(df['date'] > '2015-02-04') & (df['date'] < '2015-02-10')]

Out[59]:
         date
35 2015-02-05
36 2015-02-06
37 2015-02-07
38 2015-02-08
39 2015-02-09

How to have the cp command create any necessary folders for copying a file to a destination

 
 mkdir -p `dirname /nosuchdirectory/hi.txt` && cp -r urls-resume /nosuchdirectory/hi.txt

Python datetime - setting fixed hour and minute after using strptime to get day,month,year

If you have date as a datetime.datetime (or a datetime.date) instance and want to combine it via a time from a datetime.time instance, then you can use the classmethod datetime.datetime.combine:

import datetime
dt = datetime.datetime(2020, 7, 1)
t = datetime.time(12, 34)
combined = datetime.datetime.combine(dt.date(), t)

Textfield with only bottom border

See this JSFiddle

_x000D_
_x000D_ 
 input[type="text"]_x000D_
    {_x000D_
        border: 0;_x000D_
        border-bottom: 1px solid red;_x000D_
        outline: 0;_x000D_
    }
_x000D_ 
<form>_x000D_
        <input type="text" value="See! ONLY BOTTOM BORDER!" />_x000D_
    </form>
_x000D_
_x000D_
_x000D_

How to clear Facebook Sharer cache?

Append a ?v=random_string to the url. If you are using this idea with Facebook share, make sure that the og:url param in the response matches the url you are sharing. This will work with google plus too.

For Facebook, you can also force recrawl by making a post request to https://graph.facebook.com

{id: url,
scrape: true}

Getting Cannot bind argument to parameter 'Path' because it is null error in powershell

$_ is the active object in the current pipeline. You've started a new pipeline with $FOLDLIST | ... so $_ represents the objects in that array that are passed down the pipeline. You should stash the FileInfo object from the first pipeline in a variable and then reference that variable later e.g.:

write-host $NEWN.Length
$file = $_
...
Move-Item $file.Name $DPATH

Showing data values on stacked bar chart in ggplot2

From ggplot 2.2.0 labels can easily be stacked by using position = position_stack(vjust = 0.5) in geom_text.

ggplot(Data, aes(x = Year, y = Frequency, fill = Category, label = Frequency)) +
  geom_bar(stat = "identity") +
  geom_text(size = 3, position = position_stack(vjust = 0.5))

enter image description here

Also note that "position_stack() and position_fill() now stack values in the reverse order of the grouping, which makes the default stack order match the legend."

Answer valid for older versions of ggplot:

Here is one approach, which calculates the midpoints of the bars.

library(ggplot2)
library(plyr)

# calculate midpoints of bars (simplified using comment by @DWin)
Data <- ddply(Data, .(Year), 
   transform, pos = cumsum(Frequency) - (0.5 * Frequency)
)

# library(dplyr) ## If using dplyr... 
# Data <- group_by(Data,Year) %>%
#    mutate(pos = cumsum(Frequency) - (0.5 * Frequency))

# plot bars and add text
p <- ggplot(Data, aes(x = Year, y = Frequency)) +
     geom_bar(aes(fill = Category), stat="identity") +
     geom_text(aes(label = Frequency, y = pos), size = 3)

Resultant chart

Dynamic SQL - EXEC(@SQL) versus EXEC SP_EXECUTESQL(@SQL)

The big thing about SP_EXECUTESQL is that it allows you to create parameterized queries which is very good if you care about SQL injection.

Why is my Button text forced to ALL CAPS on Lollipop?

this one is working .... just in your code in your bottom code add this one : 

android:textAllCaps="false"

it should deactivate the caps letter that U trying to type small .

Why aren't programs written in Assembly more often?

As a developer who spends most of his time in the embedded programming world, I would argue that assembly is far from a dead/obsolete language. There is a certain close-to-the-metal level of coding (for example, in drivers) that sometimes cannot be expressed as accurately or efficiently in a higher-level language. We write nearly all of our hardware interface routines in assembler.

That being said, this assembly code is wrapped such that it can be called from C code and is treated like a library. We don't write the entire program in assembly for many reasons. First and foremost is portability; our code base is used on several products that use different architectures and we want to maximize the amount of code that can be shared between them. Second is developer familiarity. Simply put, schools don't teach assembly like they used to, and our developers are far more productive in C than in assembly. Also, we have a wide variety of "extras" (things like libraries, debuggers, static analysis tools, etc) available for our C code that aren't available for assembly language code. Even if we wanted to write a pure-assembly program, we would not be able to because several critical hardware libraries are only available as C libs. In one sense, it's a chicken/egg problem. People are driven away from assembly because there aren't as many libraries and development/debug tools available for it, but the libs/tools don't exist because not enough people use assembly to warrant the effort creating them.

In the end, there is a time and a place for just about any language. People use what they are most familiar and productive with. There will probably always be a place in a programmer's repertoire for assembly, but most programmers will find that they can write code in a higher-level language that is almost as efficient in far less time.

Copy and Paste a set range in the next empty row

The reason the code isn't working is because lastrow is measured from whatever sheet is currently active, and "A:A500" (or other number) is not a valid range reference.

Private Sub CommandButton1_Click()
    Dim lastrow As Long

    lastrow = Sheets("Summary Info").Range("A65536").End(xlUp).Row    ' or + 1
    Range("A3:E3").Copy Destination:=Sheets("Summary Info").Range("A" & lastrow)
End Sub