How to create multiple output paths in Webpack config

Please don't use any workaround because it will impact build performance.

Webpack File Manager Plugin

Easy to install copy this tag on top of the webpack.config.js

const FileManagerPlugin = require('filemanager-webpack-plugin');

Install

npm install filemanager-webpack-plugin --save-dev

Add the plugin

module.exports = {
    plugins: [
        new FileManagerPlugin({
            onEnd: {
                copy: [
                    {source: 'www', destination: './vinod test 1/'},
                    {source: 'www', destination: './vinod testing 2/'},
                    {source: 'www', destination: './vinod testing 3/'},
                ],
            },
        }),
    ],
};

Screenshot

How do I install chkconfig on Ubuntu?

The command chkconfig is no longer available in Ubuntu.The equivalent command to chkconfig is update-rc.d.This command nearly supports all the new versions of ubuntu.

The similar commands are

update-rc.d <service> defaults

update-rc.d <service> start 20 3 4 5

update-rc.d -f <service>  remove

javascript - pass selected value from popup window to parent window input box

From your code

<input type=button value="Select" onClick="sendValue(this.form.details);"

Im not sure that your this.form.details valid or not.

IF it's valid, have a look in window.opener.document.getElementById('details').value = selvalue;

I can't found an input's id contain details I'm just found only id=sku1 (recommend you to add " like id="sku1").

And from your id it's hardcode. Let's see how to do with dynamic when a child has callback to update some textbox on the parent Take a look at here.

First page.

<html>
<head>
<script>
    function callFromDialog(id,data){ //for callback from the dialog
        document.getElementById(id).value = data;
        // do some thing other if you want
    }

    function choose(id){
        var URL = "secondPage.html?id=" + id + "&dummy=avoid#";
        window.open(URL,"mywindow","menubar=1,resizable=1,width=350,height=250")
    }
</script>
</head>
<body>
<input id="tbFirst" type="text" /> <button onclick="choose('tbFirst')">choose</button>
<input id="tbSecond" type="text" /> <button onclick="choose('tbSecond')">choose</button>
</body>
</html>

Look in function choose I'm sent an id of textbox to the popup window (don't forget to add dummy data at last of URL param like &dummy=avoid#)

Popup Page

<html>
<head>
<script>
    function goSelect(data){
        var idFromCallPage = getUrlVars()["id"];
        window.opener.callFromDialog(idFromCallPage,data); //or use //window.opener.document.getElementById(idFromCallPage).value = data;
        window.close();
    }


    function getUrlVars(){
        var vars = [], hash;
        var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');
        for(var i = 0; i < hashes.length; i++)
        {
            hash = hashes[i].split('=');
            vars.push(hash[0]);
            vars[hash[0]] = hash[1];
        }
        return vars;
    }
</script>
</head>
<body>
<a href="#" onclick="goSelect('Car')">Car</a> <br />
<a href="#" onclick="goSelect('Food')">Food</a> <br />
</body>
</html>

I have add function getUrlVars for get URL param that the parent has pass to child.

Okay, when select data in the popup, for this case it's will call function goSelect

In that function will get URL param to sent back.

And when you need to sent back to the parent just use window.opener and the name of function like window.opener.callFromDialog

By fully is window.opener.callFromDialog(idFromCallPage,data);

Or if you want to use window.opener.document.getElementById(idFromCallPage).value = data; It's ok too.

Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist

In Windows run the following commands in the command prompt as adminstrator

Step 1:
mysql_install_db.exe

Step 2:
mysqld --initialize

Step 3:
mysqld --console

Step 4:
In windows

Step 4:
mysqladmin -u root password "XXXXXXX"

Step 5:
mysql -u root -p

Convert hex string to int in Python

Or ast.literal_eval (this is safe, unlike eval):

ast.literal_eval("0xffff")

Demo:

>>> import ast
>>> ast.literal_eval("0xffff")
65535
>>>

RESTful web service - how to authenticate requests from other services?

I would use have an application redirect a user to your site with an application id parameter, once the user approves the request generate a unique token that is used by the other app for authentication. This way the other applications are not handling user credentials and other applications can be added, removed and managed by users. Foursquare and a few other sites authenticate this way and its very easy to implement as the other application.

Save internal file in my own internal folder in Android

Save:

public boolean saveFile(Context context, String mytext){
    Log.i("TESTE", "SAVE");
    try {
        FileOutputStream fos = context.openFileOutput("file_name"+".txt",Context.MODE_PRIVATE);
        Writer out = new OutputStreamWriter(fos);
        out.write(mytext);
        out.close();
        return true;
    } catch (IOException e) {
        e.printStackTrace();
        return false;
    }
}

Load:

public String load(Context context){
    Log.i("TESTE", "FILE");
    try {
        FileInputStream fis = context.openFileInput("file_name"+".txt");
        BufferedReader r = new BufferedReader(new InputStreamReader(fis));
        String line= r.readLine();
        r.close();
        return line;
    } catch (IOException e) {
        e.printStackTrace();
        Log.i("TESTE", "FILE - false");
        return null;
    }
}

Extracting specific columns in numpy array

if you want to extract only some columns:

idx_IN_columns = [1, 9]
extractedData = data[:,idx_IN_columns]

if you want to exclude specific columns:

idx_OUT_columns = [1, 9]
idx_IN_columns = [i for i in xrange(np.shape(data)[1]) if i not in idx_OUT_columns]
extractedData = data[:,idx_IN_columns]

Python function global variables?

If you want to simply access a global variable you just use its name. However to change its value you need to use the global keyword.

E.g.

global someVar
someVar = 55

This would change the value of the global variable to 55. Otherwise it would just assign 55 to a local variable.

The order of function definition listings doesn't matter (assuming they don't refer to each other in some way), the order they are called does.

Get value from SimpleXMLElement Object

you can use the '{}' to access you property, and then you can do as you wish. Save it or display the content.

    $varName = $xml->{'key'};

From your example her's the code

        $filePath = __DIR__ . 'Your path ';
        $fileName = 'YourFilename.xml';

        if (file_exists($filePath . $fileName)) {
            $xml = simplexml_load_file($filePath . $fileName);
            $mainNode = $xml->{'code'};

            $cityArray = array();

            foreach ($mainNode as $key => $data)        {
               $cityArray[..] = $mainNode[$key]['cityCode'];
               ....

            }     

        }

Sizing elements to percentage of screen width/height

you can use MediaQuery with the current context of your widget and get width or height like this double width = MediaQuery.of(context).size.width double height = MediaQuery.of(context).size.height after that, you can multiply it with the percentage you want

Replace duplicate spaces with a single space in T-SQL

Found this while digging for an answer:

SELECT REPLACE(
        REPLACE(
             REPLACE(
                LTRIM(RTRIM('1 2  3   4    5     6'))
            ,'  ',' '+CHAR(7))
        ,CHAR(7)+' ','')
    ,CHAR(7),'') AS CleanString
where charindex('  ', '1 2  3   4    5     6') > 0

The full answer (with explanation) was pulled from: http://techtipsbysatish.blogspot.com/2010/08/sql-server-replace-multiple-spaces-with.html

On second look, seems to be just a slightly different version of the selected answer.

How do I `jsonify` a list in Flask?

Flask's jsonify() method now serializes top-level arrays as of this commit, available in Flask 0.11 onwards.

For convenience, you can either pass in a Python list: jsonify([1,2,3]) Or pass in a series of args: jsonify(1,2,3)

Both will be serialized to a JSON top-level array: [1,2,3]

Details here: http://flask.pocoo.org/docs/dev/api/#flask.json.jsonify

How to pull remote branch from somebody else's repo

If antak's answer:

git fetch [email protected]:<THEIR USERNAME>/<REPO>.git <THEIR BRANCH>:<OUR NAME FOR BRANCH>

gives you:

Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Then (following Przemek D's advice) use

git fetch https://github.com/<THEIR USERNAME>/<REPO>.git <THEIR BRANCH>:<OUR NAME FOR BRANCH>

Difference between h:button and h:commandButton

h:commandButton must be enclosed in a h:form and has the two ways of navigation i.e. static by setting the action attribute and dynamic by setting the actionListener attribute hence it is more advanced as follows:

<h:form>
    <h:commandButton action="page.xhtml" value="cmdButton"/>
</h:form>

this code generates the follwing html:

<form id="j_idt7" name="j_idt7" method="post" action="/jsf/faces/index.xhtml" enctype="application/x-www-form-urlencoded">

whereas the h:button is simpler and just used for static or rule based navigation as follows

<h:button outcome="page.xhtml" value="button"/>

the generated html is

 <title>Facelet Title</title></head><body><input type="button" onclick="window.location.href='/jsf/faces/page.xhtml'; return false;" value="button" />

simple vba code gives me run time error 91 object variable or with block not set

Also you are trying to set value2 using Set keyword, which is not required. You can directly use rng.value2 = 1

below test code for ref.

Sub test()
    Dim rng As Range
    Set rng = Range("A1")
    rng.Value2 = 1
End Sub

How to get an Instagram Access Token

If you don't want to build your server side, like only developing on a client side (web app or a mobile app) , you could choose an Implicit Authentication .

As the document saying , first make a https request with

https://api.instagram.com/oauth/authorize/?client_id=CLIENT-ID&redirect_uri=REDIRECT-URI&response_type=token

Fill in your CLIENT-ID and REDIRECT-URL you designated.

Then that's going to the log in page , but the most important thing is how to get the access token after the user correctly logging in.

After the user click the log in button with both correct account and password, the web page will redirect to the url you designated followed by a new access token.

http://your-redirect-uri#access_token=ACCESS-TOKEN

I'm not familiar with javascript , but in Android studio , that's an easy way to add a listener which listen to the event the web page override the url to the new url (redirect event) , then it will pass the redirect url string to you , so you can easily split it to get the access-token like:

String access_token = url.split("=")[1];

Means to break the url into the string array in each "=" character , then the access token obviously exists at [1].

Enabling/Disabling Microsoft Virtual WiFi Miniport

Microsoft Virtual WiFi Miniport should start and bind automatically to the underlying function driver. Try disabling and reenabling the AR9285 driver.

Is it possible to indent JavaScript code in Notepad++?

I think you want a code beautifier, this one looks quick and easy: http://jsbeautifier.org/

psql: server closed the connection unexepectedly

If you are using Docker make sure you are not using the same port in another service, in my case i was mistakenly using the same port for both PostgreSQL and Redis.

UML class diagram enum

They are simply showed like this:

_______________________
|   <<enumeration>>   |
|    DaysOfTheWeek    |
|_____________________|
| Sunday              |
| Monday              |
| Tuesday             |
| ...                 |
|_____________________|

And then just have an association between that and your class.

Is it correct to use alt tag for an anchor link?

"title" is widely implemented in browsers. Try:

<a href="#" title="hello">asf</a>

How can I check if a view is visible or not in Android?

Or you could simply use

View.isShown()

How can I show and hide elements based on selected option with jQuery?

To show the div while selecting one value and hide while selecting another value from dropdown box: -

 $('#yourselectorid').bind('change', function(event) {

           var i= $('#yourselectorid').val();

            if(i=="sometext") // equal to a selection option
             {
                 $('#divid').show();
             }
           elseif(i=="othertext")
             {
               $('#divid').hide(); // hide the first one
               $('#divid2').show(); // show the other one

              }
});

How can I render repeating React elements?

This is, imo, the most elegant way to do it (with ES6). Instantiate you empty array with 7 indexes and map in one line:

Array.apply(null, Array(7)).map((i)=>
<Somecomponent/>
)

kudos to https://php.quicoto.com/create-loop-inside-react-jsx/

How to add a "confirm delete" option in ASP.Net Gridview?

This is my method and it works perfectly.

asp

 <asp:CommandField ButtonType="Link" ShowEditButton="true" ShowDeleteButton="true" ItemStyle-Width="5%" HeaderStyle-Width="5%" HeaderStyle-CssClass="color" HeaderText="Edit"
                                EditText="<span style='font-size: 20px; color: #27ae60;'><span class='glyphicons glyph-edit'></span></span>"
                                DeleteText="<span style='font-size: 20px; color: #c0392b;'><span class='glyphicons glyph-bin'></span></span>"
                                CancelText="<span style='font-size: 20px; color: #c0392b;'><span class='glyphicons glyph-remove-2'></span></span>" 
                                UpdateText="<span style='font-size: 20px; color: #2980b9;'><span class='glyphicons glyph-floppy-saved'></span></span>" />

C# (replace 5 with the column number of the button)

        if ((e.Row.RowState & DataControlRowState.Edit) > 0)
        {

        }
        else {
            ((LinkButton)e.Row.Cells[5].Controls[2]).OnClientClick = "return confirm('Do you really want to delete?');";

        }

How do I center an anchor element in CSS?

You can try this code:

/**code starts here**/

a.class_name { display : block;text-align : center; }

Hash table runtime complexity (insert, search and delete)

Hash tables are O(1) average and amortized case complexity, however it suffers from O(n) worst case time complexity. [And I think this is where your confusion is]

Hash tables suffer from O(n) worst time complexity due to two reasons:

If too many elements were hashed into the same key: looking inside this key may take O(n) time.
Once a hash table has passed its load balance - it has to rehash [create a new bigger table, and re-insert each element to the table].

However, it is said to be O(1) average and amortized case because:

It is very rare that many items will be hashed to the same key [if you chose a good hash function and you don't have too big load balance.
The rehash operation, which is O(n), can at most happen after n/2 ops, which are all assumed O(1): Thus when you sum the average time per op, you get : (n*O(1) + O(n)) / n) = O(1)

Note because of the rehashing issue - a realtime applications and applications that need low latency - should not use a hash table as their data structure.

EDIT: Annother issue with hash tables: cache
Another issue where you might see a performance loss in large hash tables is due to cache performance. Hash Tables suffer from bad cache performance, and thus for large collection - the access time might take longer, since you need to reload the relevant part of the table from the memory back into the cache.

How to resize image automatically on browser width resize but keep same height?

Since you are having trouble adjusting the height you might be able to use this. http://jsfiddle.net/uf9bx/1/

img{
width: 100%;
height: 100%;
max-height: 300px;
}

I'm not sure exactly what size or location you are putting your images but maybe this will help!

What are Covering Indexes and Covered Queries in SQL Server?

A covered query is a query where all the columns in the query's result set are pulled from non-clustered indexes.

A query is made into a covered query by the judicious arrangement of indexes.

A covered query is often more performant than a non-covered query in part because non-clustered indexes have more rows per page than clustered indexes or heap indexes, so fewer pages need to be brought into memory in order to satisfy the query. They have more rows per page because only part of the table row is part of the index row.

A covering index is an index which is used in a covered query. There is no such thing as an index which, in and of itself, is a covering index. An index may be a covering index with respect to query A, while at the same time not being a covering index with respect to query B.

.NET unique object identifier

Checked out the ObjectIDGenerator class? This does what you're attempting to do, and what Marc Gravell describes.

The ObjectIDGenerator keeps track of previously identified objects. When you ask for the ID of an object, the ObjectIDGenerator knows whether to return the existing ID, or generate and remember a new ID.

The IDs are unique for the life of the ObjectIDGenerator instance. Generally, a ObjectIDGenerator life lasts as long as the Formatter that created it. Object IDs have meaning only within a given serialized stream, and are used for tracking which objects have references to others within the serialized object graph.

Using a hash table, the ObjectIDGenerator retains which ID is assigned to which object. The object references, which uniquely identify each object, are addresses in the runtime garbage-collected heap. Object reference values can change during serialization, but the table is updated automatically so the information is correct.

Object IDs are 64-bit numbers. Allocation starts from one, so zero is never a valid object ID. A formatter can choose a zero value to represent an object reference whose value is a null reference (Nothing in Visual Basic).

How to update core-js to core-js@3 dependency?

With this

npm install --save core-js@^3

you now get the error

"core-js@<3 is no longer maintained and not recommended for usage due to the number of
issues. Please, upgrade your dependencies to the actual version of core-js@3"

so you might want to instead try

npm install --save core-js@3

if you're reading this post June 9 2020.

How do I view the SSIS packages in SQL Server Management Studio?

you could find it under intergration services option in object explorer.
you could find the packages under integration services catalog where all packages are deployed.

How to add meta tag in JavaScript

Try

_x000D_

document.head.innerHTML += '<meta http-equiv="X-UA-..." content="IE=edge">'

_x000D_

git diff between two different files

Specify the paths explicitly:

git diff HEAD:full/path/to/foo full/path/to/bar

Check out the --find-renames option in the git-diff docs.

Credit: twaggs.

How many times a substring occurs

Below logic will work for all string & special characters

def cnt_substr(inp_str, sub_str):
    inp_join_str = ''.join(inp_str.split())
    sub_join_str = ''.join(sub_str.split())

    return inp_join_str.count(sub_join_str)

print(cnt_substr("the sky is   $blue and not greenthe sky is   $blue and not green", "the sky"))

How do you right-justify text in an HTML textbox?

Did you try setting the style:

input {
    text-align:right;
}

Just tested, this works fine (in FF3 at least):

<html>
    <head>
        <title>Blah</title>
        <style type="text/css">
        input { text-align:right; }
        </style>
    </head>
    <body>
        <input type="text" value="2">
    </body>
</html>

You'll probably want to throw a class on these inputs, and use that class as the selector. I would shy away from "rightAligned" or something like that. In a class name, you want to describe what the element's function is, not how it should be rendered. "numeric" might be good, or perhaps the business function of the text boxes.

CSS image resize percentage of itself?

Try zoom property

<img src="..." style="zoom: 0.5" />

Edit: Apparently, FireFox doesn't support zoom property. You should use;

-moz-transform: scale(0.5);

for FireFox.

How to getText on an input in protractor

You have to use Promise to print or store values of element.

 var ExpectedValue:string ="AllTestings.com";
          element(by.id("xyz")).getAttribute("value").then(function (Text) {

                        expect(Text.trim()).toEqual("ExpectedValue", "Wrong page navigated");//Assertion
        console.log("Text");//Print here in Console

                    });

Install windows service without InstallUtil.exe

The InstallUtil.exe tool is simply a wrapper around some reflection calls against the installer component(s) in your service. As such, it really doesn't do much but exercise the functionality these installer components provide. Marc Gravell's solution simply provides a means to do this from the command line so that you no longer have to rely on having InstallUtil.exe on the target machine.

Here's my step-by-step that based on Marc Gravell's solution.

How to make a .NET Windows Service start right after the installation?

Function pointer to member function

int (*x)() is not a pointer to member function. A pointer to member function is written like this: int (A::*x)(void) = &A::f;.

How to vertical align an inline-block in a line of text?

_x000D_

code {_x000D_
    background: black;_x000D_
    color: white;_x000D_
    display: inline-block;_x000D_
    vertical-align: middle;_x000D_
}

_x000D_

<p>Some text <code>A<br />B<br />C<br />D</code> continues afterward.</p>

_x000D_

Tested and works in Safari 5 and IE6+.

ASP.NET Web Site or ASP.NET Web Application?

A "web site" has its code in a special App_Code directory and it's compiled into several DLLs (assemblies) at runtime. A "web application" is precompiled into one single DLL.

How to execute a JavaScript function when I have its name as a string

  let t0 = () => { alert('red0') }
  var t1 = () =>{ alert('red1') }
  var t2 = () =>{ alert('red2') }
  var t3 = () =>{ alert('red3') }
  var t4 = () =>{ alert('red4') }
  var t5 = () =>{ alert('red5') }
  var t6 = () =>{ alert('red6') }

  function getSelection(type) {
    var evalSelection = {
      'title0': t0,
      'title1': t1,
      'title2': t2,
      'title3': t3,
      'title4': t4,
      'title5': t5,
      'title6': t6,
      'default': function() {
        return 'Default';
      }
    };
    return (evalSelection[type] || evalSelection['default'])();
  }
  getSelection('title1');

A more OOP solution ...

Eclipse/Maven error: "No compiler is provided in this environment"

I had a problem with Eclipse Neon where the workspace default did not actually change even though I added the correct location under Preferences->Java->Installed JREs. This was in a new workspace I created to work on a code branch; it was originally set to the JRE location rather than the JDK. Yet even after changing the preferences, I could build with the command line, yet building in Eclipse produced the no compiler error. Please see

Maven Package Compilation Error

for my answer on which Eclipse configuration file(s) had to be manually edited to make Eclipse recognize the correct workspace default. I still have no idea why the preferences setting did not carry through to the new workspace's configuration.

Postgres: clear entire database before re-creating / re-populating from bash script

If you want to clean your database named "example_db":

1) Login to another db(for example 'postgres'):

psql postgres

2) Remove your database:

DROP DATABASE example_db;

3) Recreate your database:

CREATE DATABASE example_db;

print arraylist element?

First make sure that Dog class implements the method public String toString() then use

System.out.println(list.get(index))

where index is the position inside the list. Of course since you provide your implementation you can decide how dog prints itself.

Disable mouse scroll wheel zoom on embedded Google Maps

Add this to your script:

function initMap() {
    var uluru = {lat: -25.363, lng: 131.044};
    var map = new google.maps.Map(document.getElementById('map'), {
        zoom: 12,
        center: uluru,
        scrollwheel: false,
        disableDefaultUI: true,
        disableDoubleClickZoom: true
    });
    var marker = new google.maps.Marker({
        position: uluru,
        map: map
});
}

How can I enable Assembly binding logging?

When I had the same problem I fixed it by deleting the existing key.snk in that project and adding a new key.

How can I save a screenshot directly to a file in Windows?

Is this possible:

Press Alt PrintScreen
Open a folder
Right click -> paste screenshot

Example:

Benchmark result window is open, take a screenshot. Open C:\Benchmarks Right click -> Paste screenshot A file named screenshot00x.jpg appears, with text screenshot00x selected. Type Overclock5

Thats it. No need to open anything. If you do not write anything, default name stays.

Add ... if string is too long PHP

For some of you who uses Yii2 there is a method under the hood yii\helpers\StringHelper::truncate().

Example of usage:

$sting = "stringToTruncate";
$truncatedString = \yii\helpers\StringHelper::truncate($string, 6, '...');
echo $truncatedString; // result: "string..."

Here is the doc: https://www.yiiframework.com/doc/api/2.0/yii-helpers-basestringhelper#truncate()-detail

Overlapping elements in CSS

You can use relative positioning to overlap your elements. However, the space they would normally occupy will still be reserved for the element:

<div style="background-color:#f00;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>
<div style="background-color:#0f0;width:200px;height:100px;position:relative;top:-50px;left:50px;">
    RELATIVE POSITIONED
</div>
<div style="background-color:#00f;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>

In the example above, there will be a block of white space between the two 'DEFAULT POSITIONED' elements. This is caused, because the 'RELATIVE POSITIONED' element still has it's space reserved.

If you use absolute positioning, your elements will not have any space reserved, so your element will actually overlap, without breaking your document:

<div style="background-color:#f00;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>
<div style="background-color:#0f0;width:200px;height:100px;position:absolute;top:50px;left:50px;">
    ABSOLUTE POSITIONED
</div>
<div style="background-color:#00f;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>

Finally, you can control which elements are on top of the others by using z-index:

<div style="z-index:10;background-color:#f00;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>
<div style="z-index:5;background-color:#0f0;width:200px;height:100px;position:absolute;top:50px;left:50px;">
    ABSOLUTE POSITIONED
</div>
<div style="z-index:0;background-color:#00f;width:200px;height:100px;">
    DEFAULT POSITIONED
</div>

How to convert string to integer in PowerShell

Example:

2.032 MB (2,131,022 bytes)

$u=($mbox.TotalItemSize.value).tostring()

$u=$u.trimend(" bytes)") #yields 2.032 MB (2,131,022

$u=$u.Split("(") #yields `$u[1]` as 2,131,022

$uI=[int]$u[1]

The result is 2131022 in integer form.

How to remove css property in jQuery

How to make a Python script run like a service or daemon in Linux

Ubuntu has a very simple way to manage a service. For python the difference is that ALL the dependencies (packages) have to be in the same directory, where the main file is run from.

I just manage to create such a service to provide weather info to my clients. Steps:

Create your python application project as you normally do.
Install all dependencies locally like: sudo pip3 install package_name -t .
Create your command line variables and handle them in code (if you need any)

Create the service file. Something (minimalist) like:

  [Unit]
  Description=1Droid Weather meddleware provider

  [Service]
  Restart=always
  User=root
  WorkingDirectory=/home/ubuntu/weather
  ExecStart=/usr/bin/python3 /home/ubuntu/weather/main.py httpport=9570  provider=OWMap

  [Install]
  WantedBy=multi-user.target

Save the file as myweather.service (for example)
Make sure that your app runs if started in the current directory
```
  python3  main.py httpport=9570  provider=OWMap
```
The service file produced above and named myweather.service (important to have the extension .service) will be treated by the system as the name of your service. That is the name that you will use to interact with your service.

Copy the service file:

  sudo cp myweather.service /lib/systemd/system/myweather.service

Refresh demon registry:
```
  sudo systemctl daemon-reload
```
Stop the service (if it was running)
```
  sudo service myweatherr stop
```
Start the service:
```
  sudo service myweather start
```
Check the status (log file with where your print statements go):
```
  tail -f /var/log/syslog
```
Or check the status with:
```
  sudo service myweather status
```
Back to the start with another iteration if needed

This service is now running and even if you log out it will not be affected. And YES if the host is shutdown and restarted this service will be restarted...information for my mobile android app...

What is Python used for?

Python is a dynamic, strongly typed, object oriented, multipurpose programming language, designed to be quick (to learn, to use, and to understand), and to enforce a clean and uniform syntax.

Python is dynamically typed: it means that you don't declare a type (e.g. 'integer') for a variable name, and then assign something of that type (and only that type). Instead, you have variable names, and you bind them to entities whose type stays with the entity itself. a = 5 makes the variable name a to refer to the integer 5. Later, a = "hello" makes the variable name a to refer to a string containing "hello". Static typed languages would have you declare int a and then a = 5, but assigning a = "hello" would have been a compile time error. On one hand, this makes everything more unpredictable (you don't know what a refers to). On the other hand, it makes very easy to achieve some results a static typed languages makes very difficult.
Python is strongly typed. It means that if a = "5" (the string whose value is '5') will remain a string, and never coerced to a number if the context requires so. Every type conversion in python must be done explicitly. This is different from, for example, Perl or Javascript, where you have weak typing, and can write things like "hello" + 5 to get "hello5".
Python is object oriented, with class-based inheritance. Everything is an object (including classes, functions, modules, etc), in the sense that they can be passed around as arguments, have methods and attributes, and so on.
Python is multipurpose: it is not specialised to a specific target of users (like R for statistics, or PHP for web programming). It is extended through modules and libraries, that hook very easily into the C programming language.
Python enforces correct indentation of the code by making the indentation part of the syntax. There are no control braces in Python. Blocks of code are identified by the level of indentation. Although a big turn off for many programmers not used to this, it is precious as it gives a very uniform style and results in code that is visually pleasant to read.
The code is compiled into byte code and then executed in a virtual machine. This means that precompiled code is portable between platforms.

Python can be used for any programming task, from GUI programming to web programming with everything else in between. It's quite efficient, as much of its activity is done at the C level. Python is just a layer on top of C. There are libraries for everything you can think of: game programming and openGL, GUI interfaces, web frameworks, semantic web, scientific computing...

Using COALESCE to handle NULL values in PostgreSQL

You can use COALESCE in conjunction with NULLIF for a short, efficient solution:

COALESCE( NULLIF(yourField,'') , '0' )

The NULLIF function will return null if yourField is equal to the second value ('' in the example), making the COALESCE function fully working on all cases:

                 QUERY                     |                RESULT 
---------------------------------------------------------------------------------
SELECT COALESCE(NULLIF(null  ,''),'0')     |                 '0'
SELECT COALESCE(NULLIF(''    ,''),'0')     |                 '0'
SELECT COALESCE(NULLIF('foo' ,''),'0')     |                 'foo'

T-SQL: Selecting rows to delete via joins

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

should work

How to export JSON from MongoDB using Robomongo

you say "export to file" as in a spreadsheet? like to a .csv?

IMO this is the EASIEST way to do this in Robo 3T (formerly robomongo):

In the top right of the Robo 3T GUI there is a "View Results in text mode" button, click it and copy everything
paste everything into this website: https://json-csv.com/
click the download button and now you have it in a spreadsheet.

hope this helps someone, as I wish Robo 3T had export capabilities

How Can I Override Style Info from a CSS Class in the Body of a Page?

Id's are prior to classnames.
Tag attribue 'style=' is prior to CSS selectors.
!important word is prior to first two rules.
More specific CSS selectors are prior to less specific. More specific will be applied.

for example:

.divclass .spanclass is more specific than .spanclass
.divclass.divclass is more specific than .divclass
#divId .spanclass has ID that's why it is more specific than .divClass .spanClass
<div id="someDiv" style="color:red;"> has attribute and beats #someDiv{color:blue}
style: #someDiv{color:blue!important} will be applied over attribute style="color:red"

Python convert object to float

You can use pandas.Series.astype

You can do something like this :

weather["Temp"] = weather.Temp.astype(float)

You can also use pd.to_numeric that will convert the column from object to float
For details on how to use it checkout this link :http://pandas.pydata.org/pandas-docs/version/0.20/generated/pandas.to_numeric.html

Example :

s = pd.Series(['apple', '1.0', '2', -3])
print(pd.to_numeric(s, errors='ignore'))
print("=========================")
print(pd.to_numeric(s, errors='coerce'))

Output:

0    apple
1      1.0
2        2
3       -3
=========================
dtype: object
0    NaN
1    1.0
2    2.0
3   -3.0
dtype: float64

In your case you can do something like this:

weather["Temp"] = pd.to_numeric(weather.Temp, errors='coerce')

Other option is to use convert_objects

Example is as follows

>> pd.Series([1,2,3,4,'.']).convert_objects(convert_numeric=True)

0     1
1     2
2     3
3     4
4   NaN
dtype: float64

You can use this as follows:

weather["Temp"] = weather.Temp.convert_objects(convert_numeric=True)

I have showed you examples because if any of your column won't have a number then it will be converted to NaN... so be careful while using it.

What's the scope of a variable initialized in an if statement?

Unlike languages such as C, a Python variable is in scope for the whole of the function (or class, or module) where it appears, not just in the innermost "block". It is as though you declared int x at the top of the function (or class, or module), except that in Python you don't have to declare variables.

Note that the existence of the variable x is checked only at runtime -- that is, when you get to the print x statement. If __name__ didn't equal "__main__" then you would get an exception: NameError: name 'x' is not defined.

Failed to load resource under Chrome

It is due to ad-blocker.When project files names contains words like 'ad' then ad-blockers also block theses files to load.

Best solution is that never save any files with these name keys.

How to send custom headers with requests in Swagger UI?

Here's a simpler answer for the ASP.NET Core Web Api/Swashbuckle combo, that doesn't require you to register any custom filters. Third time's a charm you know :).

Adding the code below to your Swagger config will cause the Authorize button to appear, allowing you to enter a bearer token to be sent for all requests. Don't forget to enter this token as Bearer <your token here> when asked.

Note that the code below will send the token for any and all requests and operations, which may or may not be what you want.


    services.AddSwaggerGen(c =>
    {
        //...

        c.AddSecurityDefinition("Bearer", new ApiKeyScheme()
        {
            Description = "JWT Authorization header using the Bearer scheme. Example: \"Authorization: Bearer {token}\"",
            Name = "Authorization",
            In = "header",
            Type = "apiKey"
        });

        c.AddSecurityRequirement(new Dictionary<string, IEnumerable<string>>
        {
            { "Bearer", new string[] { } }
        });

        //...
    }

Via this thread.

Centering a Twitter Bootstrap button

If you don't mind a bit more markup, this would work:

<div class="centered">
    <button class="btn btn-large btn-primary" type="button">Submit</button>
</div>

With the corresponding CSS rule:

.centered
{
    text-align:center;
}

I have to look at the CSS rules for the btn class, but I don't think it specifies a width, so auto left & right margins wouldn't work. If you added one of the span or input- rules to the button, auto margins would work, though.

Edit:

Confirmed my initial thought; the btn classes do not have a width defined, so you can't use auto side margins. Also, as @AndrewM notes, you could simply use the text-center class instead of creating a new ruleset.

Find out time it took for a python script to complete execution

use the time and datetime packages.

if anybody want to execute this script and also find out how much time it took to execute in minutes

import time
from time import strftime
from datetime import datetime 
from time import gmtime

def start_time_():    
    #import time
    start_time = time.time()
    return(start_time)

def end_time_():
    #import time
    end_time = time.time()
    return(end_time)

def Execution_time(start_time_,end_time_):
   #import time
   #from time import strftime
   #from datetime import datetime 
   #from time import gmtime
   return(strftime("%H:%M:%S",gmtime(int('{:.0f}'.format(float(str((end_time-start_time))))))))

start_time = start_time_()
# your code here #
[i for i in range(0,100000000)]
# your code here #
end_time = end_time_()
print("Execution_time is :", Execution_time(start_time,end_time))

The above code works for me. I hope this helps.

Quick Way to Implement Dictionary in C

Hashing is the key. I think use lookup table and hashing key for this. You can find many hashing function online.

JavaScript: How to join / combine two arrays to concatenate into one array?

var a = ['a','b','c'];
var b = ['d','e','f'];
var c = a.concat(b); //c is now an an array with: ['a','b','c','d','e','f']
console.log( c[3] ); //c[3] will be 'd'

how do I create an infinite loop in JavaScript

By omitting all parts of the head, the loop can also become infinite:

for (;;) {}

Post-increment and pre-increment within a 'for' loop produce same output

Both i++ and ++i is executed after printf("%d", i) is executed at each time, so there's no difference.

Safe navigation operator (?.) or (!.) and null property paths

A new library called ts-optchain provides this functionality, and unlike lodash' solution, it also keeps your types safe, here is a sample of how it is used (taken from the readme):

import { oc } from 'ts-optchain';

interface I {
  a?: string;
  b?: {
    d?: string;
  };
  c?: Array<{
    u?: {
      v?: number;
    };
  }>;
  e?: {
    f?: string;
    g?: () => string;
  };
}

const x: I = {
  a: 'hello',
  b: {
    d: 'world',
  },
  c: [{ u: { v: -100 } }, { u: { v: 200 } }, {}, { u: { v: -300 } }],
};

// Here are a few examples of deep object traversal using (a) optional chaining vs
// (b) logic expressions. Each of the following pairs are equivalent in
// result. Note how the benefits of optional chaining accrue with
// the depth and complexity of the traversal.

oc(x).a(); // 'hello'
x.a;

oc(x).b.d(); // 'world'
x.b && x.b.d;

oc(x).c[0].u.v(); // -100
x.c && x.c[0] && x.c[0].u && x.c[0].u.v;

oc(x).c[100].u.v(); // undefined
x.c && x.c[100] && x.c[100].u && x.c[100].u.v;

oc(x).c[100].u.v(1234); // 1234
(x.c && x.c[100] && x.c[100].u && x.c[100].u.v) || 1234;

oc(x).e.f(); // undefined
x.e && x.e.f;

oc(x).e.f('optional default value'); // 'optional default value'
(x.e && x.e.f) || 'optional default value';

// NOTE: working with function value types can be risky. Additional run-time
// checks to verify that object types are functions before invocation are advised!
oc(x).e.g(() => 'Yo Yo')(); // 'Yo Yo'
((x.e && x.e.g) || (() => 'Yo Yo'))();

How to declare a global variable in a .js file

Have you tried it?

If you do:

var HI = 'Hello World';

In global.js. And then do:

alert(HI);

In js1.js it will alert it fine. You just have to include global.js prior to the rest in the HTML document.

The only catch is that you have to declare it in the window's scope (not inside any functions).

You could just nix the var part and create them that way, but it's not good practice.

default value for struct member in C

An initialization function to a struct is a good way to grant it default values:

Mystruct s;
Mystruct_init(&s);

Or even shorter:

Mystruct s = Mystruct_init();  // this time init returns a struct

How to send HTML-formatted email?

Setting isBodyHtml to true allows you to use HTML tags in the message body:

msg = new MailMessage("[email protected]",
                "[email protected]", "Message from PSSP System",
                "This email sent by the PSSP system<br />" +
                "<b>this is bold text!</b>");

msg.IsBodyHtml = true;

How can I pass a parameter in Action?

You're looking for Action<T>, which takes a parameter.

Path.Combine absolute with relative path strings

For windows universal apps Path.GetFullPath() is not available, you can use the System.Uri class instead:

 Uri uri = new Uri(Path.Combine(@"C:\blah\",@"..\bling"));
 Console.WriteLine(uri.LocalPath);

Dynamically create checkbox with JQuery from text input

Put a global variable to generate the ids.

<script>
    $(function(){
        // Variable to get ids for the checkboxes
        var idCounter=1;
        $("#btn1").click(function(){
            var val = $("#txtAdd").val();
            $("#divContainer").append ( "<label for='chk_" + idCounter + "'>" + val + "</label><input id='chk_" + idCounter + "' type='checkbox' value='" + val + "' />" );
            idCounter ++;
        });
    });
</script>
<div id='divContainer'></div>
<input type="text" id="txtAdd" /> 
<button id="btn1">Click</button>

Putting an if-elif-else statement on one line?

Despite some other answers: YES it IS possible:

if expression1:
   statement1
elif expression2:
   statement2
else:
   statement3

translates to the following one liner:

statement1 if expression1 else (statement2 if expression2 else statement3)

in fact you can nest those till infinity. Enjoy ;)

Key Value Pair List

Using one of the subsets method in this question

var list = new List<KeyValuePair<string, int>>() { 
    new KeyValuePair<string, int>("A", 1),
    new KeyValuePair<string, int>("B", 0),
    new KeyValuePair<string, int>("C", 0),
    new KeyValuePair<string, int>("D", 2),
    new KeyValuePair<string, int>("E", 8),
};

int input = 11;
var items = SubSets(list).FirstOrDefault(x => x.Sum(y => y.Value)==input);

EDIT

a full console application:

using System;
using System.Collections.Generic;
using System.Linq;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            var list = new List<KeyValuePair<string, int>>() { 
                new KeyValuePair<string, int>("A", 1),
                new KeyValuePair<string, int>("B", 2),
                new KeyValuePair<string, int>("C", 3),
                new KeyValuePair<string, int>("D", 4),
                new KeyValuePair<string, int>("E", 5),
                new KeyValuePair<string, int>("F", 6),
            };

            int input = 12;
            var alternatives = list.SubSets().Where(x => x.Sum(y => y.Value) == input);

            foreach (var res in alternatives)
            {
                Console.WriteLine(String.Join(",", res.Select(x => x.Key)));
            }
            Console.WriteLine("END");
            Console.ReadLine();
        }
    }

    public static class Extenions
    {
        public static IEnumerable<IEnumerable<T>> SubSets<T>(this IEnumerable<T> enumerable)
        {
            List<T> list = enumerable.ToList();
            ulong upper = (ulong)1 << list.Count;

            for (ulong i = 0; i < upper; i++)
            {
                List<T> l = new List<T>(list.Count);
                for (int j = 0; j < sizeof(ulong) * 8; j++)
                {
                    if (((ulong)1 << j) >= upper) break;

                    if (((i >> j) & 1) == 1)
                    {
                        l.Add(list[j]);
                    }
                }

                yield return l;
            }
        }
    }
}

A circular reference was detected while serializing an object of type 'SubSonic.Schema .DatabaseColumn'.

add [JsonIgnore] to virtuals properties in your model.

AngularJS $watch window resize inside directive

// Following is angular 2.0 directive for window re size that adjust scroll bar for give element as per your tag

---- angular 2.0 window resize directive.
import { Directive, ElementRef} from 'angular2/core';

@Directive({
       selector: '[resize]',
       host: { '(window:resize)': 'onResize()' } // Window resize listener
})

export class AutoResize {

element: ElementRef; // Element that associated to attribute.
$window: any;
       constructor(_element: ElementRef) {

         this.element = _element;
         // Get instance of DOM window.
         this.$window = angular.element(window);

         this.onResize();

    }

    // Adjust height of element.
    onResize() {
         $(this.element.nativeElement).css('height', (this.$window.height() - 163) + 'px');
   }
}

Delete all the queues from RabbitMQ?

You need not reset rabbitmq server to delete non-durable queues. Simply stop the server and start again and it will remove all the non-durable queues available.

Storing images in SQL Server?

I fell into this dilemma once, and researched quite a bit on google for opinions. What I found was that indeed many see saving images to disk better for larger images, while mySQL allows for easier access, specially from languages like PHP.

I found a similar question

MySQL BLOB vs File for Storing Small PNG Images?

My final verdict was that for things such as a profile picture, just a small square image that needs to be there per user, mySQL would be better than storing a bunch of thumbs in the hdd, while for photo albums and things like that, folders/image files are better.

Hope it helps

CORS: Cannot use wildcard in Access-Control-Allow-Origin when credentials flag is true

Expanding on @Renaud idea, cors now provides a very easy way of doing this:

From cors official documentation found here:

" origin: Configures the Access-Control-Allow-Origin CORS header. Possible values: Boolean - set origin to true to reflect the request origin, as defined by req.header('Origin'), or set it to false to disable CORS. "

Hence we simply do the following:

const app = express();
const corsConfig = {
    credentials: true,
    origin: true,
};
app.use(cors(corsConfig));

Lastly I think it is worth mentioning that there are use cases where we would want to allow cross origin requests from anyone; for example, when building a public REST API.

NOTE: I would have liked to leave this as a comment on his answer, but unfortunately I don't have the reputation points.

"/usr/bin/ld: cannot find -lz"

Another possible cause: You've passed --static to the linker, but you only have a dynamic version of libz (libz.so), but not a version that can be statically linked (libz.a).

What is the best way to get the minimum or maximum value from an Array of numbers?

Math.max() is actually as3 code compiled to AVM2 opcodes, and as such is not more "native" than any other as3 code. As a consequence, it is not necessarily the fastest implementation.

Actually, given that it works on Array type, it is slower than carefully written code usign Vector:

I did a quick benchmark comparison of several naive Vector and Array implementations of Math.max, using gskinner's PerformanceTest (Vector and Array being filled with identical random Numbers). The fastest Vector implementation appeared to be more than 3x faster than Math.max with recent AIR SDK/release player (flash player WIN 14,0,0,122 RELEASE, compiled with AIR SDK 14):

average 3.5 ms for 1,000,000 values, compared to Math.max() average of 11ms :

function max(values:Vector.<Number>):Number
{
    var max:Number = Number.MIN_VALUE;
    var length:uint = values.length;
    for (var i:uint = 0; i < length ; ++i)
        if (values[i] > max)
            max = values[i];
    return max;
}

Conclusion is that if you are concerned by performance, you should use Vector over Array anywhere you can in the first place, and not always rely on default implementations, especially when they force the use of Array

PS:same implementation with a for each() loop is 12x slower ...!

Check if table exists and if it doesn't exist, create it in SQL Server 2008

Just for contrast, I like using the object_id function as shown below. It's a bit easier to read, and you don't have to worry about sys.objects vs. sysobjects vs. sys.all_objects vs. sys.tables. Basic form:

IF object_id('MyTable') is not null
    PRINT 'Present!'
ELSE
    PRINT 'Not accounted for'

Of course this will show as "Present" if there is any object present with that name. If you want to check just tables, you'd need:

IF object_id('MyTable', 'U') is not null
    PRINT 'Present!'
ELSE
    PRINT 'Not accounted for'

It works for temp tables as well:

IF object_id('tempdb.dbo.#MyTable') is not null
    PRINT 'Present!'
ELSE
    PRINT 'Not accounted for'

Regex for empty string or white space

If you're using jQuery, you have .trim().

if ($("#siren").val().trim() == "") {
  // it's empty
}

What is the difference between & and && in Java?

Besides && and || being short circuiting, also consider operator precedence when mixing the two forms. I think it will not be immediately apparent to everybody that result1 and result2 contain different values.

boolean a = true;
boolean b = false;
boolean c = false;

boolean result1 = a || b && c; //is true;  evaluated as a || (b && c)
boolean result2 = a  | b && c; //is false; evaluated as (a | b) && c

Can I force a page break in HTML printing?

You can use the CSS property page-break-before (or page-break-after). Just set page-break-before: always on those block-level elements (e.g., heading, div, p, or table elements) that should start on a new line.

For example, to cause a line break before any 2nd level heading and before any element in class newpage (e.g., <div class=newpage>...), you would use

h2, .newpage { page-break-before: always }

How to loop through all the properties of a class?

This is how I do it.

foreach (var fi in typeof(CustomRoles).GetFields())
{
    var propertyName = fi.Name;
}

MySQL IF NOT NULL, then display 1, else display 0

Plotting 4 curves in a single plot, with 3 y-axes

In your case there are 3 extra y axis (4 in total) and the best code that could be used to achieve what you want and deal with other cases is illustrated above:

clear
clc

x = linspace(0,1,10);
N = numel(x);
y = rand(1,N);
y_extra_1 = 5.*rand(1,N)+5;
y_extra_2 = 50.*rand(1,N)+20;
Y = [y;y_extra_1;y_extra_2];

xLimit = [min(x) max(x)];
xWidth = xLimit(2)-xLimit(1);
numberOfExtraPlots = 2;
a = 0.05;
N_ = numberOfExtraPlots+1;

for i=1:N_
    L=1-(numberOfExtraPlots*a)-0.2;
    axesPosition = [(0.1+(numberOfExtraPlots*a)) 0.1 L 0.8];
    if(i==1)
        color = [rand(1),rand(1),rand(1)];
        figure('Units','pixels','Position',[200 200 1200 600])
        axes('Units','normalized','Position',axesPosition,...
            'Color','w','XColor','k','YColor',color,...
            'XLim',xLimit,'YLim',[min(Y(i,:)) max(Y(i,:))],...
            'NextPlot','add');
        plot(x,Y(i,:),'Color',color);
        xlabel('Time (s)');

        ylab = strcat('Values of dataset 0',num2str(i));
        ylabel(ylab)

        numberOfExtraPlots = numberOfExtraPlots - 1;
    else
        color = [rand(1),rand(1),rand(1)];
        axes('Units','normalized','Position',axesPosition,...
            'Color','none','XColor','k','YColor',color,...
            'XLim',xLimit,'YLim',[min(Y(i,:)) max(Y(i,:))],...
            'XTick',[],'XTickLabel',[],'NextPlot','add');
        V = (xWidth*a*(i-1))/L;
        b=xLimit+[V 0];
        x_=linspace(b(1),b(2),10);
        plot(x_,Y(i,:),'Color',color);
        ylab = strcat('Values of dataset 0',num2str(i));
        ylabel(ylab)

        numberOfExtraPlots = numberOfExtraPlots - 1;
    end
end

The code above will produce something like this:

How do you get the currently selected <option> in a <select> via JavaScript?

Using the selectedOptions property:

var yourSelect = document.getElementById("your-select-id");
alert(yourSelect.selectedOptions[0].value);

It works in all browsers except Internet Explorer.

jQuery 'each' loop with JSON array

My solutions in one of my own sites, with a table:

$.getJSON("sections/view_numbers_update.php", function(data) {
 $.each(data, function(index, objNumber) {
  $('#tr_' + objNumber.intID).find("td").eq(3).html(objNumber.datLastCalled);
  $('#tr_' + objNumber.intID).find("td").eq(4).html(objNumber.strStatus);
  $('#tr_' + objNumber.intID).find("td").eq(5).html(objNumber.intDuration);
  $('#tr_' + objNumber.intID).find("td").eq(6).html(objNumber.blnWasHuman);
 });
});

sections/view_numbers_update.php Returns something like:

[{"intID":"19","datLastCalled":"Thu, 10 Jan 13 08:52:20 +0000","strStatus":"Completed","intDuration":"0:04 secs","blnWasHuman":"Yes","datModified":1357807940},
{"intID":"22","datLastCalled":"Thu, 10 Jan 13 08:54:43 +0000","strStatus":"Completed","intDuration":"0:00 secs","blnWasHuman":"Yes","datModified":1357808079}]

HTML table:

<table id="table_numbers">
 <tr>
  <th>[...]</th>
  <th>[...]</th>
  <th>[...]</th>
  <th>Last Call</th>
  <th>Status</th>
  <th>Duration</th>
  <th>Human?</th>
  <th>[...]</th>
 </tr>
 <tr id="tr_123456">
  [...]
 </tr>
</table>

This essentially gives every row a unique id preceding with 'tr_' to allow for other numbered element ids, at server script time. The jQuery script then just gets this TR_[id] element, and fills the correct indexed cell with the json return.

The advantage is you could get the complete array from the DB, and either foreach($array as $record) to create the table html, OR (if there is an update request) you can die(json_encode($array)) before displaying the table, all in the same page, but same display code.

How to create the branch from specific commit in different branch

You have the arguments in the wrong order:

git branch <branch-name> <commit>

and for that, it doesn't matter what branch is checked out; it'll do what you say. (If you omit the commit argument, it defaults to creating a branch at the same place as the current one.)

If you want to check out the new branch as you create it:

git checkout -b <branch> <commit>

with the same behavior if you omit the commit argument.

How to define a circle shape in an Android XML drawable file?

Just use

ShapeDrawable circle = new ShapeDrawable( new  OvalShape() );

Is there an ignore command for git like there is for svn?

You could also use Joe Blau's gitignore.io

Either through the web interfase https://www.gitignore.io/

Or by installing the CLI tool, it's very easy an fast, just type the following on your terminal:

Linux:
echo "function gi() { curl -L -s https://www.gitignore.io/api/\$@ ;}" >> ~/.bashrc && source ~/.bashrc

OSX:
echo "function gi() { curl -L -s https://www.gitignore.io/api/\$@ ;}" >> ~/.bash_profile && source ~/.bash_profile

And then you can just type gi followd by the all the platform/environment elements you need gitignore criteria for.

Example!
Lets say you're working on a node project that includes grunt and you're using webstorm on linux, then you may want to type:
gi linux,webstorm,node,grunt > .gitignore ( to make a brand new file)
or
gi linux,webstorm,node,grunt >> .gitignore ( to append/add the new rules to an existing file)

bam, you're good to go

wkhtmltopdf: cannot connect to X server

Update to latest wkhtmltopdf version from SourceForge (0.12 as of this writing). It does not need an X Server to run.

Example for Ubuntu 14.04:

$ cd /tmp/                                                                                                                                                                                                       
$ wget -q http://downloads.sourceforge.net/project/wkhtmltopdf/0.12.2.1/wkhtmltox-0.12.2.1_linux-trusty-amd64.deb
$ dpkg -x wkhtmltox-0.12.2.1_linux-trusty-amd64.deb foo

$ echo '<p>hi</p>' | ./foo/usr/local/bin/wkhtmltopdf - /tmp/hi.pdf
Loading pages (1/6)
Counting pages (2/6)                                               
Resolving links (4/6)                                                       
Loading headers and footers (5/6)                                           
Printing pages (6/6)
Done                                                                      

$ head -n3 /tmp/hi.pdf 
%PDF-1.4
1 0 obj
<<

Failed to instantiate module [$injector:unpr] Unknown provider: $routeProvider

The ngRoute module is no longer part of the core angular.js file. If you are continuing to use $routeProvider then you will now need to include angular-route.js in your HTML:

<script src="angular.js">
<script src="angular-route.js">

API Reference

You also have to add ngRoute as a dependency for your application:

var app = angular.module('MyApp', ['ngRoute', ...]);

If instead you are planning on using angular-ui-router or the like then just remove the $routeProvider dependency from your module .config() and substitute it with the relevant provider of choice (e.g. $stateProvider). You would then use the ui.router dependency:

var app = angular.module('MyApp', ['ui.router', ...]);

Set element width or height in Standards Mode

The style property lets you specify values for CSS properties.

The CSS width property takes a length as its value.

Lengths require units. In quirks mode, browsers tend to assume pixels if provided with an integer instead of a length. Specify units.

e1.style.width = "400px";

Multiple argument IF statement - T-SQL

Your code is valid (with one exception). It is required to have code between BEGIN and END.

Replace

--do some work

with

print ''

I think maybe you saw "END and not "AND"

Cosine Similarity between 2 Number Lists

I don't suppose performance matters much here, but I can't resist. The zip() function completely recopies both vectors (more of a matrix transpose, actually) just to get the data in "Pythonic" order. It would be interesting to time the nuts-and-bolts implementation:

import math
def cosine_similarity(v1,v2):
    "compute cosine similarity of v1 to v2: (v1 dot v2)/{||v1||*||v2||)"
    sumxx, sumxy, sumyy = 0, 0, 0
    for i in range(len(v1)):
        x = v1[i]; y = v2[i]
        sumxx += x*x
        sumyy += y*y
        sumxy += x*y
    return sumxy/math.sqrt(sumxx*sumyy)

v1,v2 = [3, 45, 7, 2], [2, 54, 13, 15]
print(v1, v2, cosine_similarity(v1,v2))

Output: [3, 45, 7, 2] [2, 54, 13, 15] 0.972284251712

That goes through the C-like noise of extracting elements one-at-a-time, but does no bulk array copying and gets everything important done in a single for loop, and uses a single square root.

ETA: Updated print call to be a function. (The original was Python 2.7, not 3.3. The current runs under Python 2.7 with a from __future__ import print_function statement.) The output is the same, either way.

CPYthon 2.7.3 on 3.0GHz Core 2 Duo:

>>> timeit.timeit("cosine_similarity(v1,v2)",setup="from __main__ import cosine_similarity, v1, v2")
2.4261788514654654
>>> timeit.timeit("cosine_measure(v1,v2)",setup="from __main__ import cosine_measure, v1, v2")
8.794677709375264

So, the unpythonic way is about 3.6 times faster in this case.

What is a good Java library to zip/unzip files?

Jasmine JavaScript Testing - toBe vs toEqual

Looking at the Jasmine source code sheds more light on the issue.

toBe is very simple and just uses the identity/strict equality operator, ===:

  function(actual, expected) {
    return {
      pass: actual === expected
    };
  }

toEqual, on the other hand, is nearly 150 lines long and has special handling for built in objects like String, Number, Boolean, Date, Error, Element and RegExp. For other objects it recursively compares properties.

This is very different from the behavior of the equality operator, ==. For example:

var simpleObject = {foo: 'bar'};
expect(simpleObject).toEqual({foo: 'bar'}); //true
simpleObject == {foo: 'bar'}; //false

var castableObject = {toString: function(){return 'bar'}};
expect(castableObject).toEqual('bar'); //false
castableObject == 'bar'; //true

Set a div width, align div center and text align left

Use auto margins.

div {
   margin-left: auto;
   margin-right: auto;
   width: NNNpx;

   /* NOTE: Only works for non-floated block elements */
   display: block;
   float: none;
}

Further reading at SimpleBits CSS Centering 101

How to sort in mongoose?

app.get('/getting',function(req,res){
    Blog.find({}).limit(4).skip(2).sort({age:-1}).then((resu)=>{
        res.send(resu);
        console.log(resu)
        // console.log(result)
    })
})

Output

[ { _id: 5c2eec3b8d6e5c20ed2f040e, name: 'e', age: 5, __v: 0 },
  { _id: 5c2eec0c8d6e5c20ed2f040d, name: 'd', age: 4, __v: 0 },
  { _id: 5c2eec048d6e5c20ed2f040c, name: 'c', age: 3, __v: 0 },
  { _id: 5c2eebf48d6e5c20ed2f040b, name: 'b', age: 2, __v: 0 } ]

"date(): It is not safe to rely on the system's timezone settings..."

Add the following in your index.php file. I first came across this when I moved my application from my XAMPP server to Apache 2.2 and PHP 5.4...

I would advise you do it in your index.php file instead of the php.ini file.

if( ! ini_get('date.timezone') )
{
    date_default_timezone_set('GMT');
}

How to $http Synchronous call with AngularJS

Not currently. If you look at the source code (from this point in time Oct 2012), you'll see that the call to XHR open is actually hard-coded to be asynchronous (the third parameter is true):

 xhr.open(method, url, true);

You'd need to write your own service that did synchronous calls. Generally that's not something you'll usually want to do because of the nature of JavaScript execution you'll end up blocking everything else.

... but.. if blocking everything else is actually desired, maybe you should look into promises and the $q service. It allows you to wait until a set of asynchronous actions are done, and then execute something once they're all complete. I don't know what your use case is, but that might be worth a look.

Outside of that, if you're going to roll your own, more information about how to make synchronous and asynchronous ajax calls can be found here.

I hope that is helpful.

C++ pass an array by reference

Like the other answer says, put the & after the *.

This brings up an interesting point that can be confusing sometimes: types should be read from right to left. For example, this is (starting from the rightmost *) a pointer to a constant pointer to an int.

int * const *x;

What you wrote would therefore be a pointer to a reference, which is not possible.

CSS styling in Django forms

Styling widget instances

If you want to make one widget instance look different from another, you will need to specify additional attributes at the time when the widget object is instantiated and assigned to a form field (and perhaps add some rules to your CSS files).

https://docs.djangoproject.com/en/2.2/ref/forms/widgets/

To do this, you use the Widget.attrs argument when creating the widget:

class CommentForm(forms.Form):
    name = forms.CharField(widget=forms.TextInput(attrs={'class': 'special'}))
    url = forms.URLField()
    comment = forms.CharField(widget=forms.TextInput(attrs={'size': '40'}))

You can also modify a widget in the form definition:

class CommentForm(forms.Form):
    name = forms.CharField()
    url = forms.URLField()
    comment = forms.CharField()

    name.widget.attrs.update({'class': 'special'})
    comment.widget.attrs.update(size='40')

Or if the field isn’t declared directly on the form (such as model form fields), you can use the Form.fields attribute:

class CommentForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.fields['name'].widget.attrs.update({'class': 'special'})
        self.fields['comment'].widget.attrs.update(size='40')

Django will then include the extra attributes in the rendered output:

>>> f = CommentForm(auto_id=False)
>>> f.as_table()
<tr><th>Name:</th><td><input type="text" name="name" class="special" required></td></tr>
<tr><th>Url:</th><td><input type="url" name="url" required></td></tr>
<tr><th>Comment:</th><td><input type="text" name="comment" size="40" required></td></tr>

Getting the computer name in Java

The computer "name" is resolved from the IP address by the underlying DNS (Domain Name System) library of the OS. There's no universal concept of a computer name across OSes, but DNS is generally available. If the computer name hasn't been configured so DNS can resolve it, it isn't available.

import java.net.InetAddress;
import java.net.UnknownHostException;

String hostname = "Unknown";

try
{
    InetAddress addr;
    addr = InetAddress.getLocalHost();
    hostname = addr.getHostName();
}
catch (UnknownHostException ex)
{
    System.out.println("Hostname can not be resolved");
}

How do I compile the asm generated by GCC?

Yes, gcc can also compile assembly source code. Alternatively, you can invoke as, which is the assembler. (gcc is just a "driver" program that uses heuristics to call C compiler, C++ compiler, assembler, linker, etc..)

Is there a decorator to simply cache function return values?

If you are using Django and want to cache views, see Nikhil Kumar's answer.

But if you want to cache ANY function results, you can use django-cache-utils.

It reuses Django caches and provides easy to use cached decorator:

from cache_utils.decorators import cached

@cached(60)
def foo(x, y=0):
    print 'foo is called'
    return x+y

setup.py examples?

Here is the utility I wrote to generate a simple setup.py file (template) with useful comments and links. I hope, it will be useful.

Installation

sudo pip install setup-py-cli

Usage

To generate setup.py file just type in the terminal.

setup-py

Now setup.py file should occur in the current directory.

Generated setup.py

from distutils.core import setup
from setuptools import find_packages
import os


# User-friendly description from README.md
current_directory = os.path.dirname(os.path.abspath(__file__))
try:
    with open(os.path.join(current_directory, 'README.md'), encoding='utf-8') as f:
        long_description = f.read()
except Exception:
    long_description = ''

setup(
    # Name of the package
    name=<name of current directory>,

    # Packages to include into the distribution
    packages=find_packages('.'), 

    # Start with a small number and increase it with every change you make
    # https://semver.org
    version='1.0.0',

    # Chose a license from here: https://help.github.com/articles/licensing-a-repository
    # For example: MIT
    license='',

    # Short description of your library
    description='',

    # Long description of your library
    long_description = long_description,
    long_description_context_type = 'text/markdown',

    # Your name
    author='', 

    # Your email
    author_email='',     

    # Either the link to your github or to your website
    url='',

    # Link from which the project can be downloaded
    download_url='',

    # List of keyword arguments
    keywords=[],

    # List of packages to install with this one
    install_requires=[],

    # https://pypi.org/classifiers/
    classifiers=[]  
)

Content of the generated setup.py:

automatically fulfilled package name based on the name of the current directory.
some basic fields to fulfill.
clarifying comments and links to useful resources.
automatically inserted description from README.md or an empty string if there is no README.md.

Here is the link to the repository. Fill free to enhance the solution.

How to add form validation pattern in Angular 2?

Now, you don't need to use FormBuilder and all this complicated valiation angular stuff. I put more details from this (Angular 2.0.8 - 3march2016): https://github.com/angular/angular/commit/38cb526

Example from repo :

<input [ngControl]="fullName" pattern="[a-zA-Z ]*">

I test it and it works :) - here is my code:

<form (ngSubmit)="onSubmit(room)" #roomForm='ngForm'  >
...
<input 
  id='room-capacity' 
  type="text" 
  class="form-control" 
  [(ngModel)]='room.capacity' 
  ngControl="capacity" 
  required
  pattern="[0-9]+" 
  #capacity='ngForm'>

Alternative approach (UPDATE June 2017)

Validation is ONLY on server side. If something is wrong then server return error code e.g HTTP 400 and following json object in response body (as example):

this.err = { 
    "capacity" : "too_small"
    "filed_name" : "error_name", 
    "field2_name" : "other_error_name",
    ... 
}

In html template I use separate tag (div/span/small etc.)

<input [(ngModel)]='room.capacity' ...>
<small *ngIf="err.capacity" ...>{{ translate(err.capacity) }}</small>

If in 'capacity' is error then tag with msg translation will be visible. This approach have following advantages:

it is very simple
avoid backend validation code duplication on frontend (for regexp validation this can either prevent or complicate ReDoS attacks)
control on way the error is shown (e.g. <small> tag)
backend return error_name which is easy to translate to proper language in frontend

Of course sometimes I make exception if validation is needed on frontend side (e.g. retypePassword field on registration is never send to server).

Can I avoid the native fullscreen video player with HTML5 on iPhone or android?

According to this page https://developer.apple.com/library/archive/documentation/AppleApplications/Reference/SafariHTMLRef/Articles/Attributes.html it is only available if (Enabled only in a UIWebView with the allowsInlineMediaPlayback property set to YES.) I understand in Mobile Safari this is YES on iPad and NO on iPhone and iPod Touch.

Convert.ToDateTime: how to set format

You can use Convert.ToDateTime is it is shown at How to convert a Datetime string to a current culture datetime string

DateTimeFormatInfo usDtfi = new CultureInfo("en-US", false).DateTimeFormat;

var result = Convert.ToDateTime("12/01/2011", usDtfi)

How to perform update operations on columns of type JSONB in Postgres 9.4

Maybe: UPDATE test SET data = '"my-other-name"'::json WHERE id = 1;

It worked with my case, where data is a json type

How do I uninstall a Windows service if the files do not exist anymore?

If you wish to use a tool for it you could use Process Hacker

Form to create the service:

Process Hacker Create Service

Context menu on a service to delete it:

Process Hacker Delete Service

I find Process Hacker a more convient tool to manage Windows processes and services than Windows's own Taskmgr.exe. Especially on Windows XP, where you can't access services at all from task manager.

What is main.py?

If your script is a directory or ZIP file rather than a single python file, __main__.py will be executed when the "script" is passed as an argument to the python interpreter.

How do I update Node.js?

To upgrade node to the latest version or to a specific version you can do the following:

sudo npm install n -g
sudo n 0.10.18   // This will give you the specific version

For the latest stable version:

sudo n stable

For the latest LTS version(Tested on Mac)

sudo n lts

Change content of div - jQuery

You can try the same with replacewith()

$('.click').click(function() {
    // get the contents of the link that was clicked
    var linkText = $(this).text();

    // replace the contents of the div with the link text
    $('#content-container').replaceWith(linkText);

    // cancel the default action of the link by returning false
    return false;
});

The .replaceWith() method removes content from the DOM and inserts new content in its place with a single call.

How do you implement a re-try-catch?

Obligatory "enterprisy" solution:

public abstract class Operation {
    abstract public void doIt();
    public void handleException(Exception cause) {
        //default impl: do nothing, log the exception, etc.
    }
}

public class OperationHelper {
    public static void doWithRetry(int maxAttempts, Operation operation) {
        for (int count = 0; count < maxAttempts; count++) {
            try {
                operation.doIt();
                count = maxAttempts; //don't retry
            } catch (Exception e) {
                operation.handleException(e);
            }
        }
    }
}

And to call:

OperationHelper.doWithRetry(5, new Operation() {
    @Override public void doIt() {
        //do some stuff
    }
    @Override public void handleException(Exception cause) {
        //recover from the Exception
    }
});

TypeError: Cannot read property "0" from undefined

Check your array index to see if it's accessed out of bound.

Once I accessed categories[0]. Later I changed the array name from categories to category but forgot to change the access point--from categories[0] to category[0], thus I also get this error.

JavaScript does a poor debug message. In your case, I reckon probably the access gets out of bound.

Partly cherry-picking a commit with Git

Use git format-patch to slice out the part of the commit you care about and git am to apply it to another branch

git format-patch <sha> -- path/to/file
git checkout other-branch
git am *.patch

How to add multiple files to Git at the same time

It sounds like git is launching your editor (probably vi) so that you can type a commit message. If you are not familiar with vi, it is easy to learn the basics. Alternatives are:

Use git commit -a -m "my first commit message" to specify the commit message on the command line (using this will not launch an editor)
Set the EDITOR environment variable to an editor that you are familiar with

Convert String to Calendar Object in Java

Parse a time with timezone, Z in pattern is for time zone

String aTime = "2017-10-25T11:39:00+09:00";
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ", Locale.getDefault());
try {
    Calendar cal = Calendar.getInstance();
    cal.setTime(sdf.parse(aTime));
    Log.i(TAG, "time = " + cal.getTimeInMillis()); 
} catch (ParseException e) {
    e.printStackTrace();
}

Output: it will return the UTC time

1508899140000

If we don't set the time zone in pattern like yyyy-MM-dd'T'HH:mm:ss. SimpleDateFormat will use the time zone which have set in Setting

Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)

Based on Kapitán Mlíko's answer with source above, I would change it to use the following:

Marlett Font Example

It's a better practice to use the Marlett font rather than Path Data points for the Minimize, Restore/Maximize and Close buttons.

<StackPanel Orientation="Horizontal" HorizontalAlignment="Right" VerticalAlignment="Top" WindowChrome.IsHitTestVisibleInChrome="True" Grid.Row="0">
<Button Command="{Binding Source={x:Static SystemCommands.MinimizeWindowCommand}}" ToolTip="minimize" Style="{StaticResource WindowButtonStyle}">
    <Button.Content>
        <Grid Width="30" Height="25">
            <TextBlock Text="0" FontFamily="Marlett" FontSize="14" VerticalAlignment="Center" HorizontalAlignment="Center" Padding="3.5,0,0,3" />
        </Grid>
    </Button.Content>
</Button>
<Grid Margin="1,0,1,0">
    <Button x:Name="Restore" Command="{Binding Source={x:Static SystemCommands.RestoreWindowCommand}}" ToolTip="restore" Visibility="Collapsed" Style="{StaticResource WindowButtonStyle}">
        <Button.Content>
            <Grid Width="30" Height="25" UseLayoutRounding="True">
                <TextBlock Text="2" FontFamily="Marlett" FontSize="14" VerticalAlignment="Center" HorizontalAlignment="Center" Padding="2,0,0,1" />
            </Grid>
        </Button.Content>
    </Button>
    <Button x:Name="Maximize" Command="{Binding Source={x:Static SystemCommands.MaximizeWindowCommand}}" ToolTip="maximize" Style="{StaticResource WindowButtonStyle}">
        <Button.Content>
            <Grid Width="31" Height="25">
                <TextBlock Text="1" FontFamily="Marlett" FontSize="14" VerticalAlignment="Center" HorizontalAlignment="Center" Padding="2,0,0,1" />
            </Grid>
        </Button.Content>
    </Button>
</Grid>
<Button Command="{Binding Source={x:Static SystemCommands.CloseWindowCommand}}" ToolTip="close"  Style="{StaticResource WindowButtonStyle}">
    <Button.Content>
        <Grid Width="30" Height="25">
            <TextBlock Text="r" FontFamily="Marlett" FontSize="14" VerticalAlignment="Center" HorizontalAlignment="Center" Padding="0,0,0,1" />
        </Grid>
    </Button.Content>
</Button>

How do I create 7-Zip archives with .NET?

These easiest way is to work with .zip files instead of .7z and use Dot Net Zip

When spinning off 7zip commands to shell there are other issues like user privileges, I had issue with SevenZipSharp.

Private Function CompressFile(filename As String) As Boolean
Using zip As New ZipFile()
    zip.AddFile(filename & ".txt", "")
    zip.Save(filename & ".zip")
End Using

Return File.Exists(filename & ".zip")
End Function

How do I output an ISO 8601 formatted string in JavaScript?

Almost every to-ISO method on the web drops the timezone information by applying a convert to "Z"ulu time (UTC) before outputting the string. Browser's native .toISOString() also drops timezone information.

This discards valuable information, as the server, or recipient, can always convert a full ISO date to Zulu time or whichever timezone it requires, while still getting the timezone information of the sender.

The best solution I've come across is to use the Moment.js javascript library and use the following code:

To get the current ISO time with timezone information and milliseconds

now = moment().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T20:11:11.234+0100"

now = moment().utc().format("YYYY-MM-DDTHH:mm:ss.SSSZZ")
// "2013-03-08T19:11:11.234+0000"

now = moment().utc().format("YYYY-MM-DDTHH:mm:ss") + "Z"
// "2013-03-08T19:11:11Z" <- better use the native .toISOString()

To get the ISO time of a native JavaScript Date object with timezone information but without milliseconds

var current_time = Date.now();
moment(current_time).format("YYYY-MM-DDTHH:mm:ssZZ")

This can be combined with Date.js to get functions like Date.today() whose result can then be passed to moment.

A date string formatted like this is JSON compilant, and lends itself well to get stored into a database. Python and C# seem to like it.

Git push error '[remote rejected] master -> master (branch is currently checked out)'

I had the same problem using Git to synchronise repositories on my Android phone and laptop. The solution for me was to do a pull instead of a push, as @CharlesBailey suggested.

git push origin master on the Android repository fails for me with the same error messages that @hap497 got because of a push to a nonbare checkout of a repository + working-copy.

git pull droid master on the laptop repository and working-copy works for me. Of course, you need to have previously run something like git remote add droid /media/KINGSTON4GB/notes_repo/.

How to pip or easy_install tkinter on Windows

if your using python 3.4.1 just write this line from tkinter import * this will put everything in the module into the default namespace of your program. in fact instead of referring to say a button like tkinter.Button you just type Button

Docker: Copying files from Docker container to host

In order to copy a file from a container to the host, you can use the command

docker cp <containerId>:/file/path/within/container /host/path/target

Here's an example:

$ sudo docker cp goofy_roentgen:/out_read.jpg .

Here goofy_roentgen is the container name I got from the following command:

$ sudo docker ps

CONTAINER ID        IMAGE               COMMAND             CREATED             STATUS              PORTS                                            NAMES
1b4ad9311e93        bamos/openface      "/bin/bash"         33 minutes ago      Up 33 minutes       0.0.0.0:8000->8000/tcp, 0.0.0.0:9000->9000/tcp   goofy_roentgen

You can also use (part of) the Container ID. The following command is equivalent to the first

$ sudo docker cp 1b4a:/out_read.jpg .

1064 error in CREATE TABLE ... TYPE=MYISAM

Try the below query

CREATE TABLE card_types (
  card_type_id int(11) NOT NULL auto_increment,
  name varchar(50) NOT NULL default '',
  PRIMARY KEY  (card_type_id),
) ENGINE = MyISAM ;

DbEntityValidationException - How can I easily tell what caused the error?

I think "The actual validation errors" may contain sensitive information, and this could be the reason why Microsoft chose to put them in another place (properties). The solution marked here is practical, but it should be taken with caution.

I would prefer to create an extension method. More reasons to this:

Keep original stack trace
Follow open/closed principle (ie.: I can use different messages for different kind of logs)
In production environments there could be other places (ie.: other dbcontext) where a DbEntityValidationException could be thrown.

What are your favorite extension methods for C#? (codeplex.com/extensionoverflow)

Another useful one for me:

/// <summary>
/// Converts any type in to an Int32
/// </summary>
/// <typeparam name="T">Any Object</typeparam>
/// <param name="value">Value to convert</param>
/// <returns>The integer, 0 if unsuccessful</returns>
public static int ToInt32<T>(this T value)
{
  int result;
  if (int.TryParse(value.ToString(), out result))
  {
    return result;
  }
  return 0;
}

/// <summary>
/// Converts any type in to an Int32 but if null then returns the default
/// </summary>
/// <param name="value">Value to convert</param>
/// <typeparam name="T">Any Object</typeparam>
/// <param name="defaultValue">Default to use</param>
/// <returns>The defaultValue if unsuccessful</returns>
public static int ToInt32<T>(this T value, int defaultValue)
{
  int result;
  if (int.TryParse(value.ToString(), out result))
  {
    return result;
  }
  return defaultValue;
}

Example:

int number = "123".ToInt32();

or:

int badNumber = "a".ToInt32(100); // Returns 100 since a is nan

Set maxlength in Html Textarea

If you are using HTML 5, you need to specify that in your DOCTYPE declaration.

For a valid HTML 5 document, it should start with:

<!DOCTYPE html>

Before HTML 5, the textarea element did not have a maxlength attribute.

You can see this in the DTD/spec:

<!ELEMENT TEXTAREA - - (#PCDATA)       -- multi-line text field -->
<!ATTLIST TEXTAREA
  %attrs;                              -- %coreattrs, %i18n, %events --
  name        CDATA          #IMPLIED
  rows        NUMBER         #REQUIRED
  cols        NUMBER         #REQUIRED
  disabled    (disabled)     #IMPLIED  -- unavailable in this context --
  readonly    (readonly)     #IMPLIED
  tabindex    NUMBER         #IMPLIED  -- position in tabbing order --
  accesskey   %Character;    #IMPLIED  -- accessibility key character --
  onfocus     %Script;       #IMPLIED  -- the element got the focus --
  onblur      %Script;       #IMPLIED  -- the element lost the focus --
  onselect    %Script;       #IMPLIED  -- some text was selected --
  onchange    %Script;       #IMPLIED  -- the element value was changed --
  %reserved;                           -- reserved for possible future use --
  >

In order to limit the number of characters typed into a textarea, you will need to use javascript with the onChange event. You can then count the number of characters and disallow further typing.

Here is an in-depth discussion on text input and how to use server and client side scripting to limit the size.

Here is another sample.

Display more Text in fullcalendar

For some reason, I have to use

element.find('.fc-event-inner').empty();

to make it work, i guess i'm in day view.

Get folder up one level

The parent directory of an included file would be

dirname(getcwd())

e.g. the file is /var/www/html/folder/inc/file.inc.php which is included in /var/www/html/folder/index.php

then by calling /file/index.php

getcwd() is /var/www/html/folder  
__DIR__ is /var/www/html/folder/inc  
so dirname(__DIR__) is /var/www/html/folder

but what we want is /var/www/html which is dirname(getcwd())

How do I zip two arrays in JavaScript?

Use the map method:

_x000D_

var a = [1, 2, 3]_x000D_
var b = ['a', 'b', 'c']_x000D_
_x000D_
var c = a.map(function(e, i) {_x000D_
  return [e, b[i]];_x000D_
});_x000D_
_x000D_
console.log(c)

_x000D_

DEMO

What is the difference between join and merge in Pandas?

To put it analogously to SQL "Pandas merge is to outer/inner join and Pandas join is to natural join". Hence when you use merge in pandas, you want to specify which kind of sqlish join you want to use whereas when you use pandas join, you really want to have a matching column label to ensure it joins

How does DHT in torrents work?

The general theory can be found in wikipedia's article on Kademlia. The specific protocol specification used in bittorrent is here: http://wiki.theory.org/BitTorrentDraftDHTProtocol

How to suppress "unused parameter" warnings in C?

In gcc, you can label the parameter with the unused attribute.

This attribute, attached to a variable, means that the variable is meant to be possibly unused. GCC will not produce a warning for this variable.

In practice this is accomplished by putting __attribute__ ((unused)) just before the parameter. For example:

void foo(workerid_t workerId) { }

becomes

void foo(__attribute__((unused)) workerid_t workerId) { }

How to convert date to string and to date again?

try this:

 String DATE_FORMAT_NOW = "yyyy-MM-dd";
 Date date = new Date();
 SimpleDateFormat sdf = new SimpleDateFormat(DATE_FORMAT_NOW);
 String stringDate = sdf.format(date );
    try {
        Date date2 = sdf.parse(stringDate);
    } catch(ParseException e){
     //Exception handling
    } catch(Exception e){
     //handle exception
    }

ReferenceError: describe is not defined NodeJs

if you are using vscode, want to debug your files

I used tdd before, it throw ReferenceError: describe is not defined

But, when I use bdd, it works!

waste half day to solve it....

    {
      "type": "node",
      "request": "launch",
      "name": "Mocha Tests",
      "program": "${workspaceFolder}/node_modules/mocha/bin/_mocha",
      "args": [
        "-u",
        "bdd",// set to bdd, not tdd
        "--timeout",
        "999999",
        "--colors",
        "${workspaceFolder}/test/**/*.js"
      ],
      "internalConsoleOptions": "openOnSessionStart"
},

VarBinary vs Image SQL Server Data Type to Store Binary Data?

varbinary(max) is the way to go (introduced in SQL Server 2005)

unable to remove file that really exists - fatal: pathspec ... did not match any files

Your file .idea/workspace.xml is not under git version control. You have either not added it yet (check git status/Untracked files) or ignored it (using .gitignore or .git/info/exclude files)

You can verify it using following git command, that lists all ignored files:

git ls-files --others -i --exclude-standard

How to fix Invalid byte 1 of 1-byte UTF-8 sequence

You have a library that needs to be erased Like the following library

   implementation 'org.apache.maven.plugins:maven-surefire-plugin:2.4.3'

Input Type image submit form value?

I was in the same place as you, finally I found a neat answer :

<form action="xx/xx" method="POST">
  <input type="hidden" name="what you want" value="what you want">
  <input type="image" src="xx.xx">
</form>

How do I change the data type for a column in MySQL?

alter table table_name modify column_name int(5)

git: How to diff changed files versus previous versions after a pull?

If you do a straight git pull then you will either be 'fast-forwarded' or merge an unknown number of commits from the remote repository. This happens as one action though, so the last commit that you were at immediately before the pull will be the last entry in the reflog and can be accessed as HEAD@{1}. This means that you can do:

git diff HEAD@{1}

However, I would strongly recommend that if this is something you find yourself doing a lot then you should consider just doing a git fetch and examining the fetched branch before manually merging or rebasing onto it. E.g. if you're on master and were going to pull in origin/master:

git fetch

git log HEAD..origin/master

 # looks good, lets merge

git merge origin/master

How to change the type of a field?

To convert a field of string type to date field, you would need to iterate the cursor returned by the find() method using the forEach() method, within the loop convert the field to a Date object and then update the field using the $set operator.

Take advantage of using the Bulk API for bulk updates which offer better performance as you will be sending the operations to the server in batches of say 1000 which gives you a better performance as you are not sending every request to the server, just once in every 1000 requests.

The following demonstrates this approach, the first example uses the Bulk API available in MongoDB versions >= 2.6 and < 3.2. It updates all the documents in the collection by changing all the created_at fields to date fields:

var bulk = db.collection.initializeUnorderedBulkOp(),
    counter = 0;

db.collection.find({"created_at": {"$exists": true, "$type": 2 }}).forEach(function (doc) {
    var newDate = new Date(doc.created_at);
    bulk.find({ "_id": doc._id }).updateOne({ 
        "$set": { "created_at": newDate}
    });

    counter++;
    if (counter % 1000 == 0) {
        bulk.execute(); // Execute per 1000 operations and re-initialize every 1000 update statements
        bulk = db.collection.initializeUnorderedBulkOp();
    }
})
// Clean up remaining operations in queue
if (counter % 1000 != 0) { bulk.execute(); }

The next example applies to the new MongoDB version 3.2 which has since deprecated the Bulk API and provided a newer set of apis using bulkWrite():

var bulkOps = [];

db.collection.find({"created_at": {"$exists": true, "$type": 2 }}).forEach(function (doc) { 
    var newDate = new Date(doc.created_at);
    bulkOps.push(         
        { 
            "updateOne": { 
                "filter": { "_id": doc._id } ,              
                "update": { "$set": { "created_at": newDate } } 
            }         
        }           
    );     
})

db.collection.bulkWrite(bulkOps, { "ordered": true });

Node.js/Express routing with get params

For Query parameters like domain.com/test?format=json&type=mini format, then you can easily receive it via - req.query.

app.get('/test', function(req, res){
  var format = req.query.format,
      type = req.query.type;
});

Spring: @Component versus @Bean

Let's consider I want specific implementation depending on some dynamic state. @Bean is perfect for that case.

@Bean
@Scope("prototype")
public SomeService someService() {
    switch (state) {
    case 1:
        return new Impl1();
    case 2:
        return new Impl2();
    case 3:
        return new Impl3();
    default:
        return new Impl();
    }
}

However there is no way to do that with @Component.

Read a file in Node.js

Use path.join(__dirname, '/start.html');

var fs = require('fs'),
    path = require('path'),    
    filePath = path.join(__dirname, 'start.html');

fs.readFile(filePath, {encoding: 'utf-8'}, function(err,data){
    if (!err) {
        console.log('received data: ' + data);
        response.writeHead(200, {'Content-Type': 'text/html'});
        response.write(data);
        response.end();
    } else {
        console.log(err);
    }
});

How can I add comments in MySQL?

"A comment for a column can be specified with the COMMENT option. The comment is displayed by the SHOW CREATE TABLE and SHOW FULL COLUMNS statements. This option is operational as of MySQL 4.1. (It is allowed but ignored in earlier versions.)"

As an example

--
-- Table structure for table 'accesslog'
--

CREATE TABLE accesslog (
aid int(10) NOT NULL auto_increment COMMENT 'unique ID for each access entry', 
title varchar(255) default NULL COMMENT 'the title of the page being accessed',
path varchar(255) default NULL COMMENT 'the local path of teh page being accessed',
....
) TYPE=MyISAM;

Interface defining a constructor signature?

I was looking back at this question and I thought to myself, maybe we are aproaching this problem the wrong way. Interfaces might not be the way to go when it concerns defining a constructor with certain parameters... but an (abstract) base class is.

If you create a base class with a constructor on there that accepts the parameters you need, every class that derrives from it needs to supply them.

public abstract class Foo
{
  protected Foo(SomeParameter x)
  {
    this.X = x;
  }

  public SomeParameter X { get; private set }
}

public class Bar : Foo // Bar inherits from Foo
{
  public Bar() 
    : base(new SomeParameter("etc...")) // Bar will need to supply the constructor param
  {
  }
}

SEVERE: ContainerBase.addChild: start:org.apache.catalina.LifecycleException: Failed to start error

What helped me was deleting my target folder and recompile my project again. This problem occured to me when I used a second server for my tests that needed a server running. Conclusion: delete your target file when you make big changes to the war file.

Arguments to main in C

Main is just like any other function and argc and argv are just like any other function arguments, the difference is that main is called from C Runtime and it passes the argument to main, But C Runtime is defined in c library and you cannot modify it, So if we do execute program on shell or through some IDE, we need a mechanism to pass the argument to main function so that your main function can behave differently on the runtime depending on your parameters. The parameters are argc , which gives the number of arguments and argv which is pointer to array of pointers, which holds the value as strings, this way you can pass any number of arguments without restricting it, it's the other way of implementing var args.

Using a Python subprocess call to invoke a Python script

First, check if somescript.py is executable and starts with something along the lines of #!/usr/bin/python. If this is done, then you can use subprocess.call('./somescript.py').

Or as another answer points out, you could do subprocess.call(['python', 'somescript.py']).

What is the simplest and most robust way to get the user's current location on Android?

In the Activity Class makes a customized method :

private void getTheUserPermission() {
        ActivityCompat.requestPermissions(this, new String[]
                {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);
        locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        LocationGetter locationGetter = new LocationGetter(FreshMenuSearchActivity.this, REQUEST_LOCATION, locationManager);


        if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {

            locationGetter.OnGPS();
        } else {

            locationGetter.getLocation();
        }
    }

Make a UserDefined Class name LocationGetter:-

public class LocationGetter {

        private int REQUEST_LOCATION;
        private FreshMenuSearchActivity mContext;
        private LocationManager locationManager;
        private Geocoder geocoder;

        public LocationGetter(FreshMenuSearchActivity mContext, int requestLocation, LocationManager locationManager) {
            this.mContext = mContext;
            this.locationManager = locationManager;
            this.REQUEST_LOCATION = requestLocation;
        }


        public void getLocation() {

            if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(mContext,

                    Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(mContext, new String[]
                        {Manifest.permission.ACCESS_FINE_LOCATION}, REQUEST_LOCATION);
            } else {
                Location LocationGps = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
                Location LocationNetwork = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                Location LocationPassive = locationManager.getLastKnownLocation(LocationManager.PASSIVE_PROVIDER);

                if (LocationGps != null) {
                    double lat = LocationGps.getLatitude();
                    double longi = LocationGps.getLongitude();
                    getTheAddress(lat, longi);
                } else if (LocationNetwork != null) {
                    double lat = LocationNetwork.getLatitude();
                    double longi = LocationNetwork.getLongitude();
                    getTheAddress(lat, longi);
                } else if (LocationPassive != null) {
                    double lat = LocationPassive.getLatitude();
                    double longi = LocationPassive.getLongitude();
                    getTheAddress(lat, longi);
                } else {
                    Toast.makeText(mContext, "Can't Get Your Location", Toast.LENGTH_SHORT).show();
                }

            }

        }

        private void getTheAddress(double latitude, double longitude) {
            List<Address> addresses;
            geocoder = new Geocoder(mContext, Locale.getDefault());

            try {
                addresses = geocoder.getFromLocation(latitude, longitude, 1);
                String address = addresses.get(0).getAddressLine(0);
                String city = addresses.get(0).getLocality();
                String state = addresses.get(0).getAdminArea();
                String country = addresses.get(0).getCountryName();
                String postalCode = addresses.get(0).getPostalCode();
                String knownName = addresses.get(0).getFeatureName();
                Log.d("neel", address);
            } catch (IOException e) {
                e.printStackTrace();
            }


        }

        public void OnGPS() {

            final AlertDialog.Builder builder = new AlertDialog.Builder(mContext);

            builder.setMessage("Enable GPS").setCancelable(false).setPositiveButton("YES", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {
                    mContext.startActivity(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS));
                }
            }).setNegativeButton("NO", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                    dialog.cancel();
                }
            });
            final AlertDialog alertDialog = builder.create();
            alertDialog.show();
        }

    }

Can't update data-attribute value

This answer is for those seeking to just change the value of a data-attribute

The suggested will not change the value of your Jquery data-attr correctly as @adeneo has stated. For some reason though, I'm not seeing him (or any others) post the correct method for those seeking to update their data-attr. The answer that @Lucas Willems has posted may be the answer to problem Brian Tompsett - ??? is having, but it's not the answer to the inquiry that may be bringing other users here.

Quick answer in regards to original inquiry statement

-To update data-attr

$('#ElementId').attr('data-attributeTitle',newAttributeValue);

Easy mistakes* - there must be "data-" at the beginning of your attribute you're looking to change the value of.

Django error - matching query does not exist

your line raising the error is here:

comment = Comment.objects.get(pk=comment_id)

you try to access a non-existing comment.

from django.shortcuts import get_object_or_404

comment = get_object_or_404(Comment, pk=comment_id)

Instead of having an error on your server, your user will get a 404 meaning that he tries to access a non existing resource.

Ok up to here I suppose you are aware of this.

Some users (and I'm part of them) let tabs running for long time, if users are authorized to delete data, it may happens. A 404 error may be a better error to handle a deleted resource error than sending an email to the admin.

Other users go to addresses from their history, (same if data have been deleted since it may happens).

disable editing default value of text input

I don't think all the other answerers understood the question correctly. The question requires disabling editing part of the text. One solution I can think of is simulating a textbox with a fixed prefix which is not part of the textarea or input.

An example of this approach is:

<div style="border:1px solid gray; color:#999999; font-family:arial; font-size:10pt; width:200px; white-space:nowrap;">Default Notes<br/>
<textarea style="border:0px solid black;" cols="39" rows="5"></textarea></div>

The other approach, which I end up using is using JS and JQuery to simulate "Disable" feature. Example with pseudo-code (cannot be specific cause of legal issue):

  // disable existing notes by preventing keystroke
  document.getElementById("txtNotes").addEventListener('keydown', function (e) {
    if (cursorLocation < defaultNoteLength ) {
            e.preventDefault();
  });

    // disable existing notes by preventing right click
    document.addEventListener('contextmenu', function (e) {
        if (cursorLocation < defaultNoteLength )
            e.preventDefault();
    });

Thanks, Carsten, for mentioning that this question is old, but I found that the solution might help other people in the future.

How do I group Windows Form radio buttons?

GroupBox is better.But not only group box, even you can use Panels (System.Windows.Forms.Panel).

That is very usefully when you are designing Internet Protocol version 4 setting dialog.(Check it with your pc(windows),then you can understand the behavior)

How to move mouse cursor using C#?

First Add a Class called Win32.cs

public class Win32
{ 
    [DllImport("User32.Dll")]
    public static extern long SetCursorPos(int x, int y);

    [DllImport("User32.Dll")]
    public static extern bool ClientToScreen(IntPtr hWnd, ref POINT point);

    [StructLayout(LayoutKind.Sequential)]
    public struct POINT
    {
        public int x;
        public int y;

        public POINT(int X, int Y)
        {
            x = X;
            y = Y;
        }
    }
}

You can use it then like this:

Win32.POINT p = new Win32.POINT(xPos, yPos);

Win32.ClientToScreen(this.Handle, ref p);
Win32.SetCursorPos(p.x, p.y);

How to hide the Google Invisible reCAPTCHA badge

Since hiding the badge is not really legit as per the TOU, and existing placement options were breaking my UI and/or UX, I've come up with the following customization that mimics fixed positioning, but is instead rendered inline:

You just need to apply some CSS on your badge container:

.badge-container {
  display: flex;
  justify-content: flex-end;
  overflow: hidden;
  width: 70px;
  height: 60px;
  margin: 0 auto;
  box-shadow: 0 0 4px #ddd;
  transition: linear 100ms width;
}
.badge-container:hover {
    width: 256px;
}

I think that's as far as you can legally push it.

Dealing with timestamps in R

You want the (standard) POSIXt type from base R that can be had in 'compact form' as a POSIXct (which is essentially a double representing fractional seconds since the epoch) or as long form in POSIXlt (which contains sub-elements). The cool thing is that arithmetic etc are defined on this -- see help(DateTimeClasses)

Quick example:

R> now <- Sys.time()
R> now
[1] "2009-12-25 18:39:11 CST"
R> as.numeric(now)
[1] 1.262e+09
R> now + 10  # adds 10 seconds
[1] "2009-12-25 18:39:21 CST"
R> as.POSIXlt(now)
[1] "2009-12-25 18:39:11 CST"
R> str(as.POSIXlt(now))
 POSIXlt[1:9], format: "2009-12-25 18:39:11"
R> unclass(as.POSIXlt(now))
$sec
[1] 11.79

$min
[1] 39

$hour
[1] 18

$mday
[1] 25

$mon
[1] 11

$year
[1] 109

$wday
[1] 5

$yday
[1] 358

$isdst
[1] 0

attr(,"tzone")
[1] "America/Chicago" "CST"             "CDT"            
R>

As for reading them in, see help(strptime)

As for difference, easy too:

R> Jan1 <- strptime("2009-01-01 00:00:00", "%Y-%m-%d %H:%M:%S")
R> difftime(now, Jan1, unit="week")
Time difference of 51.25 weeks
R>

Lastly, the zoo package is an extremely versatile and well-documented container for matrix with associated date/time indices.

How can I define an array of objects?

You are better off using a native array instead of an object literal with number-like properties, so that numbering (as well as numerous other array functions) are taken care of off-the-shelf.

What you are looking for here is an inline interface definition for your array that defines every element in that array, whether initially present or introduced later:

let userTestStatus: { id: number, name: string }[] = [
    { "id": 0, "name": "Available" },
    { "id": 1, "name": "Ready" },
    { "id": 2, "name": "Started" }
];

userTestStatus[34978].nammme; // Error: Property 'nammme' does not exist on type [...]

If you are initializing your array with values right away, the explicit type definition is not a necessity; TypeScript can automatically infer most element types from the initial assignment:

let userTestStatus = [
    { "id": 0, "name": "Available" },
    ...
];

userTestStatus[34978].nammme; // Error: Property 'nammme' does not exist on type [...]

How to identify whether a grammar is LL(1), LR(0) or SLR(1)?

If you have no FIRST/FIRST conflicts and no FIRST/FOLLOW conflicts, your grammar is LL(1).

An example of a FIRST/FIRST conflict:

S -> Xb | Yc
X -> a 
Y -> a

By seeing only the first input symbol a, you cannot know whether to apply the production S -> Xb or S -> Yc, because a is in the FIRST set of both X and Y.

An example of a FIRST/FOLLOW conflict:

S -> AB 
A -> fe | epsilon 
B -> fg

By seeing only the first input symbol f, you cannot decide whether to apply the production A -> fe or A -> epsilon, because f is in both the FIRST set of A and the FOLLOW set of A (A can be parsed as epsilon and B as f).

Notice that if you have no epsilon-productions you cannot have a FIRST/FOLLOW conflict.

How to send 500 Internal Server Error error from a PHP script

Your code should look like:

<?php
if ( that_happened ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

if ( something_else_happened ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

// Your function should return FALSE if something goes wrong
if ( !update_database() ) {
    header("HTTP/1.0 500 Internal Server Error");
    die();
}

// the script can also fail on the above line
// e.g. a mysql error occurred


header('HTTP/1.1 200 OK');
?>

I assume you stop execution if something goes wrong.

Can we have multiple "WITH AS" in single sql - Oracle SQL

Aditya or others, can you join or match up t2 with t1 in your example, i.e. translated to my code,

with t1 as (select * from AA where FIRSTNAME like 'Kermit'),
     t2 as (select * from BB B join t1 on t1.FIELD1 = B.FIELD1)

I am not clear whether only WHERE is supported for joining, or what joining approach is supported within the 2nd WITH entity. Some of the examples have the WHERE A=B down in the body of the select "below" the WITH clauses.

The error I'm getting following these WITH declarations is the identifiers (field names) in B are not recognized, down in the body of the rest of the SQL. So the WITH syntax seems to run OK, but cannot access the results from t2.

Convert string (without any separator) to list

Did you try list(x)??

 y = '+123-456-7890'
 c =list(y)
 c

['+', '1', '2', '3', '-', '4', '5', '6', '-', '7', '8', '9', '0']

How can I convert a series of images to a PDF from the command line on linux?

Using imagemagick, you can try:

convert page.png page.pdf

Or for multiple images:

convert page*.png mydoc.pdf

Handling multiple IDs in jQuery

Solution:

To your secondary question

var elem1 = $('#elem1'),
    elem2 = $('#elem2'),
    elem3 = $('#elem3');

You can use the variable as the replacement of selector.

elem1.css({'display':'none'}); //will work

In the below case selector is already stored in a variable.

$(elem1,elem2,elem3).css({'display':'none'}); // will not work

CSS filter: make color image with transparency white

To my knowledge, there is sadly no CSS filter to colorise an element (perhaps with the use of some SVG filter magic, but I'm somewhat unfamiliar with that) and even if that wasn't the case, filters are basically only supported by webkit browsers.

With that said, you could still work around this and use a canvas to modify your image. Basically, you can draw an image element onto a canvas and then loop through the pixels, modifying the respective RGBA values to the colour you want.

However, canvases do come with some restrictions. Most importantly, you have to make sure that the image src comes from the same domain as the page. Otherwise the browser won't allow you to read or modify the pixel data of the canvas.

Here's a JSFiddle changing the colour of the JSFiddle logo.

_x000D_

//Base64 source, but any local source will work_x000D_
var src = "data:image/png;base64,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";_x000D_
var canvas = document.getElementById("theCanvas");_x000D_
var ctx = canvas.getContext("2d");_x000D_
var img = new Image;_x000D_
_x000D_
//wait for the image to load_x000D_
img.onload = function() {_x000D_
    //Draw the original image so that you can fetch the colour data_x000D_
    ctx.drawImage(img,0,0);_x000D_
    var imgData = ctx.getImageData(0, 0, canvas.width, canvas.height);_x000D_
    _x000D_
    /*_x000D_
    imgData.data is a one-dimensional array which contains _x000D_
    the respective RGBA values for every pixel _x000D_
    in the selected region of the context _x000D_
    (note i+=4 in the loop)_x000D_
    */_x000D_
    _x000D_
    for (var i = 0; i < imgData.data.length; i+=4) {_x000D_
   imgData.data[i] = 255; //Red, 0-255_x000D_
   imgData.data[i+1] = 255; //Green, 0-255_x000D_
   imgData.data[i+2] = 255; //Blue, 0-255_x000D_
   /* _x000D_
   imgData.data[i+3] contains the alpha value_x000D_
   which we are going to ignore and leave_x000D_
   alone with its original value_x000D_
   */_x000D_
    }_x000D_
    ctx.clearRect(0, 0, canvas.width, canvas.height); //clear the original image_x000D_
    ctx.putImageData(imgData, 0, 0); //paint the new colorised image_x000D_
}_x000D_
_x000D_
//Load the image!_x000D_
img.src = src;

_x000D_

body {_x000D_
    background: green;_x000D_
}

_x000D_

<canvas id="theCanvas"></canvas>

_x000D_

In nodeJs is there a way to loop through an array without using array size?

You can use Array.forEach

_x000D_

var myArray = ['1','2',3,4]_x000D_
_x000D_
myArray.forEach(function(value){_x000D_
  console.log(value);_x000D_
});

_x000D_

remove kernel on jupyter notebook

Run jupyter kernelspec list to get the paths of all your kernels.
Then simply uninstall your unwanted-kernel

jupyter kernelspec uninstall unwanted-kernel

Old answer
Delete the folder corresponding to the kernel you want to remove.

The docs has a list of the common paths for kernels to be stored in: http://jupyter-client.readthedocs.io/en/latest/kernels.html#kernelspecs

What is the meaning of ImagePullBackOff status on a Kubernetes pod?

One issue that may cause an ImagePullBackOff especially if you are pulling from a private registry is if the pod is not configured with the imagePullSecret of the private registry.

An authentication error may cause an imagePullBackOff.

When should I use nil and NULL in Objective-C?

nil is an object pointer to nothing. Although semantically distinct from NULL, they are technically equivalent to one another.

On the framework level, Foundation defines NSNull, which defines a class method, +null, which returns the singleton NSNull object. NSNull is different from nil or NULL, in that it is an actual object, rather than a zero value.

Additionally, in Foundation/NSObjCRuntime.h, Nil is defined as a class pointer to nothing.

Refer this for further info - nil / Nil / NULL / NSNull

How to install PHP mbstring on CentOS 6.2

Please check your /etc/yum.conf file, maybe it is exclude php packages.

You should remove php* from this line so you can download php-* packages:

exclude= courier* dovecot* exim* filesystem httpd* mod_ssl* mydns* php*

It's seems your server having some scripts like cPanel

Check a collection size with JSTL

As suggested by @Joel and @Mark Chorley in earlier comments:

${empty companies}

This checks for null and empty lists/collections/arrays. It doesn't get you the length but it satisfies the example in the OP. If you can get away with it this is just cleaner than importing a tag library and its crusty syntax like gt.

Undo a Git merge that hasn't been pushed yet

I think you can do git rebase -i [hash] [branch_name] where [hash] is the identifying hash for however far back you want to rewind plus one (or however many commits back you want to go) and then delete the lines for the commits in the editor that you don't want any more. Save the file. Exit. Pray. And it should be rewound. You might have to do a git reset --hard, but it should be good at this point. You can also use this to pull specific commits out of a stack, if you don't want to keep them in your history, but that can leave your repository in a state that you probably don't want.

Flexbox and Internet Explorer 11 (display:flex in <html>?)

Here is an example of using flex that also works in Internet Explorer 11 and Chrome.

HTML

_x000D_

<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
<meta http-equiv="X-UA-Compatible" content="IE=Edge,chrome=1" >_x000D_
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" >_x000D_
<title>Flex Test</title>_x000D_
<style>_x000D_
html, body {_x000D_
    margin: 0px;_x000D_
    padding: 0px;_x000D_
    height: 100vh;_x000D_
}_x000D_
.main {_x000D_
    display: -webkit-flex;_x000D_
    display: flex;_x000D_
    -ms-flex-direction: row;_x000D_
    flex-direction: row;_x000D_
    align-items: stretch;_x000D_
    min-height: 100vh;_x000D_
}_x000D_
_x000D_
.main::after {_x000D_
  content: '';_x000D_
  height: 100vh;_x000D_
  width: 0;_x000D_
  overflow: hidden;_x000D_
  visibility: hidden;_x000D_
  float: left;_x000D_
}_x000D_
_x000D_
.left {_x000D_
    width: 200px;_x000D_
    background: #F0F0F0;_x000D_
    flex-shrink: 0;_x000D_
}_x000D_
_x000D_
.right {_x000D_
    flex-grow: 1;_x000D_
    background: yellow;_x000D_
}_x000D_
</style>_x000D_
</head>_x000D_
_x000D_
<body>_x000D_
<div class="main">_x000D_
    <div class="left">_x000D_
        <div style="height: 300px;">_x000D_
        </div>_x000D_
    </div>_x000D_
_x000D_
    <div class="right">_x000D_
        <div style="height: 1000px;">_x000D_
            test test test_x000D_
        </div>_x000D_
    </div>_x000D_
</div>_x000D_
</body>_x000D_
</html>

_x000D_

What is the simplest way to get indented XML with line breaks from XmlDocument?

XmlTextWriter xw = new XmlTextWriter(writer);
xw.Formatting = Formatting.Indented;

VB.NET 'If' statement with 'Or' conditional has both sides evaluated?

It's your "fault" in that that's how Or is defined, so it's the behaviour you should expect:

In a Boolean comparison, the Or operator always evaluates both expressions, which could include making procedure calls. The OrElse Operator (Visual Basic) performs short-circuiting, which means that if expression1 is True, then expression2 is not evaluated.

But you don't have to endure it. You can use OrElse to get short-circuiting behaviour.

So you probably want:

If (example Is Nothing OrElse Not example.Item = compare.Item) Then
    'Proceed
End If

I can't say it reads terribly nicely, but it should work...

Android View shadow

This question may be old, but for anybody in future that wants a simple way to achieve complex shadow effects check out my library here https://github.com/BluRe-CN/ComplexView

Using the library, you can change shadow colors, tweak edges and so much more. Here's an example to achieve what you seek for.

<com.blure.complexview.ComplexView
        android:layout_width="400dp"
        android:layout_height="600dp"
        app:radius="10dp"
        app:shadow="true"
        app:shadowSpread="2">

        <com.blure.complexview.ComplexView
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            app:color="#fdfcfc"
            app:radius="10dp" />
    </com.blure.complexview.ComplexView>

To change the shadow color, use app:shadowColor="your color code".

How to query MongoDB with "like"?

Here is the command which uses starts with paradigm

db.customer.find({"customer_name" : { $regex : /^startswith/ }})

Does a favicon have to be 32x32 or 16x16?

May I remind everybody that the question was:

I'd like to use a single image as both a regular favicon and iPhone/iPad friendly favicon? Is this possible? Would an iPad-friendly 72x72 PNG scale if linked to as a regular browser favicon? Or do I have to use a separate 16x16 or 32x32 image?

The answer is: YES, that is possible! YES, it will be scaled. NO, you do not need a 'regular browser favicon'. Please look at this answer: https://stackoverflow.com/a/48646940/2397550

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

You could have a static method that looks at HttpContext.Current and decides which URL to use (development or live server) depending on the host ID. HttpContext might even offer some easier way to do it, but this is the first option I found and it works fine.

Python: Assign print output to a variable

This is a standalone example showing how to save the output of a user-written function in Python 3:

from io import StringIO
import sys

def print_audio_tagging_result(value):
    print(f"value = {value}")

tag_list = []
for i in range(0,1):
    save_stdout = sys.stdout
    result = StringIO()
    sys.stdout = result
    print_audio_tagging_result(i)
    sys.stdout = save_stdout
    tag_list.append(result.getvalue())
print(tag_list)

init and arguments in Python

The fact that your method does not use the self argument (which is a reference to the instance that the method is attached to) doesn't mean you can leave it out. It always has to be there, because Python is always going to try to pass it in.

Combine Multiple child rows into one row MYSQL

What you want is called a pivot, and it's not directly supported in MySQL, check this answer out for the options you've got:

How to pivot a MySQL entity-attribute-value schema

Getting android.content.res.Resources$NotFoundException: exception even when the resource is present in android

I have fixed the by this way:

Create a folder in your resource directory name "drawable-nodpi" and then move yours all resources in this directory from others drawable directory.

Now clean your project and then rebuilt. Run again hopefully it will work this time without any resource not found exception.

How do I deal with corrupted Git object files?

In general, fixing corrupt objects can be pretty difficult. However, in this case, we're confident that the problem is an aborted transfer, meaning that the object is in a remote repository, so we should be able to safely remove our copy and let git get it from the remote, correctly this time.

The temporary object file, with zero size, can obviously just be removed. It's not going to do us any good. The corrupt object which refers to it, d4a0e75..., is our real problem. It can be found in .git/objects/d4/a0e75.... As I said above, it's going to be safe to remove, but just in case, back it up first.

At this point, a fresh git pull should succeed.

...assuming it was going to succeed in the first place. In this case, it appears that some local modifications prevented the attempted merge, so a stash, pull, stash pop was in order. This could happen with any merge, though, and didn't have anything to do with the corrupted object. (Unless there was some index cleanup necessary, and the stash did that in the process... but I don't believe so.)

Vue equivalent of setTimeout?

Arrow Function

The best and simplest way to solve this problem is by using an arrow function () => {}:

    addToBasket() {
        var item = this.photo;
        this.$http.post('/api/buy/addToBasket', item);
        this.basketAddSuccess = true;
        // now 'this' is referencing the Vue object and not the 'setTimeout' scope
        setTimeout(() => this.basketAddSuccess = false, 2000);
    }

This works because the this of arrow functions is bound to the this of its enclosing scope- in Vue, that's the parent/ enclosing component. Inside a traditional function called by setTimeout, however, this refers to the window object (which is why you ran into errors when you tried to access this.basketAddSuccess in that context).

Argument Passing

Another way of doing this would be passing this as an arg to your function through setTimeout's prototype using its setTimeout(callback, delay, arg1, arg2, ...) form:

    addToBasket() {
        item = this.photo;
        this.$http.post('/api/buy/addToBasket', item);
        this.basketAddSuccess = true;
        //Add scope argument to func, pass this after delay in setTimeout
        setTimeout(function(scope) {
             scope.basketAddSuccess = false;
        }, 2000, this);
    }

(It's worth noting that the arg passing syntax is incompatible with IE 9 and below, however.)

Local Variable

Another possible, but less eloquent and less encouraged, way is to bind this to a var outside of setTimeout:

    addToBasket() {
        item = this.photo;
        this.$http.post('/api/buy/addToBasket', item);
        this.basketAddSuccess = true;
        //Declare self, which is accessible inside setTimeout func
        var self = this;
        setTimeout(function() {
             self.basketAddSuccess = false;
        }, 2000);
    }

Using an arrow function would eliminate the need for this extra variable entirely however, and really should be used unless something else is preventing its use.

Converting a number with comma as decimal point to float

Assuming they are in a file or array just do the replace as a batch (i.e. on all at once):

$input = str_replace(array('.', ','), array('', '.'), $input);

and then process the numbers from there taking full advantage of PHP's loosely typed nature.

Flatten nested dictionaries, compressing keys

def flatten(unflattened_dict, separator='_'):
    flattened_dict = {}

    for k, v in unflattened_dict.items():
        if isinstance(v, dict):
            sub_flattened_dict = flatten(v, separator)
            for k2, v2 in sub_flattened_dict.items():
                flattened_dict[k + separator + k2] = v2
        else:
            flattened_dict[k] = v

    return flattened_dict

How do I prevent and/or handle a StackOverflowException?

From Microsoft:

Starting with the .NET Framework version 2.0, a StackOverflowException object cannot be caught by a try-catch block and the corresponding process is terminated by default. Consequently, users are advised to write their code to detect and prevent a stack overflow. For example, if your application depends on recursion, use a counter or a state condition to terminate the recursive loop.

I'm assuming the exception is happening within an internal .NET method, and not in your code.

You can do a couple things.

Write code that checks the xsl for infinite recursion and notifies the user prior to applying a transform (Ugh).
Load the XslTransform code into a separate process (Hacky, but less work).

You can use the Process class to load the assembly that will apply the transform into a separate process, and alert the user of the failure if it dies, without killing your main app.

EDIT: I just tested, here is how to do it:

MainProcess:

// This is just an example, obviously you'll want to pass args to this.
Process p1 = new Process();
p1.StartInfo.FileName = "ApplyTransform.exe";
p1.StartInfo.UseShellExecute = false;
p1.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;

p1.Start();
p1.WaitForExit();

if (p1.ExitCode == 1)    
   Console.WriteLine("StackOverflow was thrown");

ApplyTransform Process:

class Program
{
    static void Main(string[] args)
    {
        AppDomain.CurrentDomain.UnhandledException += new UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
        throw new StackOverflowException();
    }

    // We trap this, we can't save the process, 
    // but we can prevent the "ILLEGAL OPERATION" window 
    static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
    {
        if (e.IsTerminating)
        {
            Environment.Exit(1);
        }
    }
}

jQuery/Javascript function to clear all the fields of a form

To reset form (but not clear the form) just trigger reset event:

$('#form').trigger("reset");

To clear a form see other answers.

Convert timestamp to date in MySQL query

You should convert timestamp to date.

select FROM_UNIXTIME(user.registration, '%Y-%m-%d %H:%i:%s') AS 'date_formatted'

FROM_UNIXTIME

Possible to change where Android Virtual Devices are saved?

For Visual Studio 2017 on Windows 10

Copy C:\Users\YOURUSERNAME\.android folder to (for example) E:\avd

Open the environment variables window:

Go into Settings and click on System.
On the left, click About and select System info at the bottom.
In the new window, click Advanced system settings on the left.
Click Environment Variables at the bottom of the resulting window.

Add a new variable:

Variable name: ANDROID_SDK_HOME
Variable value: a path to a directory (e.g E:\avd)

Don't include .android in the variable value.

Restart Visual Studio.

For change SDK & NDK location go to:

Tools -> Options -> Xamarin -> Android Setting

Eclipse Bug: Unhandled event loop exception No more handles

I had this issue after installing HP ProtectTools on HP Probook 6470b, because of included Password Manager.

To disable it run "HP ProtectTools Administrative Console", go to "Applications->Settings", open "Applications" tab and uncheck "Status" checkbox.

After PC restart problem should be solved, but you can't use Password Manager anymore :(

Programs & Examples On #Kconfig

How to create multiple output paths in Webpack config

How do I install chkconfig on Ubuntu?

javascript - pass selected value from popup window to parent window input box

First page.

Popup Page

Fatal error: Can't open and lock privilege tables: Table 'mysql.host' doesn't exist

Convert hex string to int in Python

RESTful web service - how to authenticate requests from other services?

Save internal file in my own internal folder in Android

Extracting specific columns in numpy array

Python function global variables?

Get value from SimpleXMLElement Object

Sizing elements to percentage of screen width/height

Replace duplicate spaces with a single space in T-SQL

How do I `jsonify` a list in Flask?

How to pull remote branch from somebody else's repo

Difference between h:button and h:commandButton

simple vba code gives me run time error 91 object variable or with block not set

How to get an Instagram Access Token

Enabling/Disabling Microsoft Virtual WiFi Miniport

Is it possible to indent JavaScript code in Notepad++?

psql: server closed the connection unexepectedly

UML class diagram enum

Is it correct to use alt tag for an anchor link?

How can I check if a view is visible or not in Android?

How can I show and hide elements based on selected option with jQuery?

How can I render repeating React elements?

How to add a "confirm delete" option in ASP.Net Gridview?

How do I center an anchor element in CSS?

Hash table runtime complexity (insert, search and delete)

How to resize image automatically on browser width resize but keep same height?

What are Covering Indexes and Covered Queries in SQL Server?

.NET unique object identifier

How to update core-js to core-js@3 dependency?

How do I view the SSIS packages in SQL Server Management Studio?

How to add meta tag in JavaScript

git diff between two different files

How many times a substring occurs

How do you right-justify text in an HTML textbox?

CSS image resize percentage of itself?

How to getText on an input in protractor

Install windows service without InstallUtil.exe

Function pointer to member function

How to vertical align an inline-block in a line of text?

ASP.NET Web Site or ASP.NET Web Application?

How to execute a JavaScript function when I have its name as a string

Eclipse/Maven error: "No compiler is provided in this environment"

Postgres: clear entire database before re-creating / re-populating from bash script

print arraylist element?

Disable mouse scroll wheel zoom on embedded Google Maps

How can I enable Assembly binding logging?

How can I save a screenshot directly to a file in Windows?

Add ... if string is too long PHP

Overlapping elements in CSS

How to convert string to integer in PowerShell

How to remove css property in jQuery

How to make a Python script run like a service or daemon in Linux

What is Python used for?

Using COALESCE to handle NULL values in PostgreSQL

T-SQL: Selecting rows to delete via joins

How to export JSON from MongoDB using Robomongo

How Can I Override Style Info from a CSS Class in the Body of a Page?

Python convert object to float

What's the scope of a variable initialized in an if statement?

Failed to load resource under Chrome

How to send custom headers with requests in Swagger UI?

Centering a Twitter Bootstrap button

Find out time it took for a python script to complete execution

Quick Way to Implement Dictionary in C

JavaScript: How to join / combine two arrays to concatenate into one array?

how do I create an infinite loop in JavaScript

Post-increment and pre-increment within a 'for' loop produce same output

Safe navigation operator (?.) or (!.) and null property paths

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default value for struct member in C

How to send HTML-formatted email?

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Path.Combine absolute with relative path strings

Dynamically create checkbox with JQuery from text input

What is main.py?