upstream sent too big header while reading response header from upstream

Plesk instructions

I combined the top two answers here

In Plesk 12, I had nginx running as a reverse proxy (which I think is the default). So the current top answer doesn't work as nginx is also being run as a proxy.

I went to Subscriptions | [subscription domain] | Websites & Domains (tab) | [Virtual Host domain] | Web Server Settings.

Then at the bottom of that page you can set the Additional nginx directives which I set to be a combination of the top two answers here:

fastcgi_buffers         16  16k;
fastcgi_buffer_size         32k;
proxy_buffer_size          128k;
proxy_buffers            4 256k;
proxy_busy_buffers_size    256k;

Bundler::GemNotFound: Could not find rake-10.3.2 in any of the sources

I think rake must be preinstalled if you want work with bundler. Try to install rake via 'gem install' and then run 'bundle install' again:

gem install rake && bundle install

If you are using rvm ( http://rvm.io ) rake is installed by default...

Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference

The other answers are excellent and I just want to provide a straight forward answer to this. Just limiting to jQuery asynchronous calls

All ajax calls (including the $.get or $.post or $.ajax) are asynchronous.

Considering your example

var outerScopeVar;  //line 1
$.post('loldog', function(response) {  //line 2
    outerScopeVar = response;
});
alert(outerScopeVar);  //line 3

The code execution starts from line 1, declares the variable and triggers and asynchronous call on line 2, (i.e., the post request) and it continues its execution from line 3, without waiting for the post request to complete its execution.

Lets say that the post request takes 10 seconds to complete, the value of outerScopeVar will only be set after those 10 seconds.

To try out,

var outerScopeVar; //line 1
$.post('loldog', function(response) {  //line 2, takes 10 seconds to complete
    outerScopeVar = response;
});
alert("Lets wait for some time here! Waiting is fun");  //line 3
alert(outerScopeVar);  //line 4

Now when you execute this, you would get an alert on line 3. Now wait for some time until you are sure the post request has returned some value. Then when you click OK, on the alert box, next alert would print the expected value, because you waited for it.

In real life scenario, the code becomes,

var outerScopeVar;
$.post('loldog', function(response) {
    outerScopeVar = response;
    alert(outerScopeVar);
});

All the code that depends on the asynchronous calls, is moved inside the asynchronous block, or by waiting on the asynchronous calls.

how to use json file in html code

You can use JavaScript like... Just give the proper path of your json file...

<!doctype html>
<html>
    <head>
        <script type="text/javascript" src="abc.json"></script>
        <script type="text/javascript" >
            function load() {
                var mydata = JSON.parse(data);
                alert(mydata.length);

                var div = document.getElementById('data');

                for(var i = 0;i < mydata.length; i++)
                {
                    div.innerHTML = div.innerHTML + "<p class='inner' id="+i+">"+ mydata[i].name +"</p>" + "<br>";
                }
            }
        </script>
    </head>
    <body onload="load()">
        <div id="data">

        </div>
    </body>
</html>

Simply getting the data and appending it to a div... Initially printing the length in alert.

Here is my Json file: abc.json

data = '[{"name" : "Riyaz"},{"name" : "Javed"},{"name" : "Arun"},{"name" : "Sunil"},{"name" : "Rahul"},{"name" : "Anita"}]';

How to start rails server?

For newest Rails versions

If you have trouble with rails s, sometimes terminal fails.

And you should try to use:

./bin/rails

To access command.

Ruby String to Date Conversion

str = "Tue, 10 Aug 2010 01:20:19 -0400 (EDT)"
str.to_date
=> Tue, 10 Aug 2010

Do copyright dates need to be updated?

So, if it's a static content (such as the Times article you linked to), it should probably be statically copyrighted.

If it's dynamically generated content, it should be copyrighted to the current year

Leave only two decimal places after the dot

Using the property of String

double value = 123.456789;
String.Format("{0:0.00}", value);

Note: This can be used to display only.

Using System.Math

double value = 123.456789;
System.Math.Round(value, 2);

Update TextView Every Second

Use TextSwitcher (for nice text transition animation) and timer instead.

Limit file format when using <input type="file">?

I know this is a bit late.

function Validatebodypanelbumper(theForm)
{
   var regexp;
   var extension =     theForm.FileUpload.value.substr(theForm.FileUpload1.value.lastIndexOf('.'));
   if ((extension.toLowerCase() != ".gif") &&
       (extension.toLowerCase() != ".jpg") &&
       (extension != ""))
   {
      alert("The \"FileUpload\" field contains an unapproved filename.");
      theForm.FileUpload1.focus();
      return false;
   }
   return true;
}

How do I do a HTTP GET in Java?

If you want to stream any webpage, you can use the method below.

import java.io.*;
import java.net.*;

public class c {

   public static String getHTML(String urlToRead) throws Exception {
      StringBuilder result = new StringBuilder();
      URL url = new URL(urlToRead);
      HttpURLConnection conn = (HttpURLConnection) url.openConnection();
      conn.setRequestMethod("GET");
      try (var reader = new BufferedReader(
                  new InputStreamReader(conn.getInputStream()))) {
          for (String line; (line = reader.readLine()) != null; ) {
              result.append(line);
          }
      }
      return result.toString();
   }

   public static void main(String[] args) throws Exception
   {
     System.out.println(getHTML(args[0]));
   }
}

How to concatenate properties from multiple JavaScript objects

function collect(a, b, c){
    var d = {};

    for(p in a){
        d[p] = a[p];
    }
    for(p in b){
        d[p] = b[p];
    }
    for(p in c){
        d[p] = c[p];
    }

    return d;
}

Get URL query string parameters

Also if you are looking for current file name along with the query string, you will just need following

basename($_SERVER['REQUEST_URI'])

It would provide you info like following example

file.php?arg1=val&arg2=val

And if you also want full path of file as well starting from root, e.g. /folder/folder2/file.php?arg1=val&arg2=val then just remove basename() function and just use fillowing

$_SERVER['REQUEST_URI']

JSON Parse File Path

My case of working code is:

var request = new XMLHttpRequest();
request.open("GET", "<path_to_file>", false);
request.overrideMimeType("application/json");
request.send(null);
var jsonData = JSON.parse(request.responseText);
console.log(jsonData);

Could not load file or assembly Microsoft.SqlServer.management.sdk.sfc version 11.0.0.0

I am running VS 2012, and SQL Server 2008 R2 SP2, Developer Edition. I ended up having to install items from the Microsoft® SQL Server® 2012 Feature Pack. I think that the install instructions noted that these items work for SQL Server 2005 through 2012. I don't know what the exact requirements are to fix this error, but I installed the three items, and the error stopped appearing.

Microsoft® SQL Server® 2012 Feature Pack Items

Microsoft® SQL Server® 2012 Shared Management Objects : x86 , x64
Microsoft® System CLR Types for Microsoft® SQL Server® 2012 : x86 , x64
Microsoft® SQL Server® 2012 Native Client : x86 , x64

Based on threads elsewhere, you may not end up needing the last item or two. Good luck!

How can I start an interactive console for Perl?

re.pl from Devel::REPL

Calculating the distance between 2 points

You can use the below formula to find the distance between the 2 points:

distance*distance = ((x2 - x1)*(x2 - x1)) + ((y2 - y1)*(y2 - y1))

Adding header for HttpURLConnection

Step 1: Get HttpURLConnection object

URL url = new URL(urlToConnect);
HttpURLConnection httpUrlConnection = (HttpURLConnection) url.openConnection();

Step 2: Add headers to the HttpURLConnection using setRequestProperty method.

Map<String, String> headers = new HashMap<>();

headers.put("X-CSRF-Token", "fetch");
headers.put("content-type", "application/json");

for (String headerKey : headers.keySet()) {
    httpUrlConnection.setRequestProperty(headerKey, headers.get(headerKey));
}

Reference link

Relative Paths in Javascript in an external file

Please use the following syntax to enjoy the luxury of asp.net tilda ("~") in javascript

<script src=<%=Page.ResolveUrl("~/MasterPages/assets/js/jquery.js")%>></script>

How to create an array containing 1...N

to get array with n random numbers between min, max (not unique though)

function callItWhatYouWant(n, min, max) {
    return Array.apply(null, {length: n}).map(Function.call, function(){return Math.floor(Math.random()*(max-min+1)+min)})
}

Print text instead of value from C enum

TheDay maps back to some integer type. So:

printf("%s", TheDay);

Attempts to parse TheDay as a string, and will either print out garbage or crash.

printf is not typesafe and trusts you to pass the right value to it. To print out the name of the value, you'd need to create some method for mapping the enum value to a string - either a lookup table, giant switch statement, etc.

How to sort an associative array by its values in Javascript?

Javascript doesn't have "associative arrays" the way you're thinking of them. Instead, you simply have the ability to set object properties using array-like syntax (as in your example), plus the ability to iterate over an object's properties.

The upshot of this is that there is no guarantee as to the order in which you iterate over the properties, so there is nothing like a sort for them. Instead, you'll need to convert your object properties into a "true" array (which does guarantee order). Here's a code snippet for converting an object into an array of two-tuples (two-element arrays), sorting it as you describe, then iterating over it:

var tuples = [];

for (var key in obj) tuples.push([key, obj[key]]);

tuples.sort(function(a, b) {
    a = a[1];
    b = b[1];

    return a < b ? -1 : (a > b ? 1 : 0);
});

for (var i = 0; i < tuples.length; i++) {
    var key = tuples[i][0];
    var value = tuples[i][1];

    // do something with key and value
}

You may find it more natural to wrap this in a function which takes a callback:

_x000D_

function bySortedValue(obj, callback, context) {_x000D_
  var tuples = [];_x000D_
_x000D_
  for (var key in obj) tuples.push([key, obj[key]]);_x000D_
_x000D_
  tuples.sort(function(a, b) {_x000D_
    return a[1] < b[1] ? 1 : a[1] > b[1] ? -1 : 0_x000D_
  });_x000D_
_x000D_
  var length = tuples.length;_x000D_
  while (length--) callback.call(context, tuples[length][0], tuples[length][1]);_x000D_
}_x000D_
_x000D_
bySortedValue({_x000D_
  foo: 1,_x000D_
  bar: 7,_x000D_
  baz: 3_x000D_
}, function(key, value) {_x000D_
  document.getElementById('res').innerHTML += `${key}: ${value}<br>`_x000D_
});

_x000D_

<p id='res'>Result:<br/><br/><p>

_x000D_

Use SQL Server Management Studio to connect remotely to an SQL Server Express instance hosted on an Azure Virtual Machine

The fact that you're getting an error from the Names Pipes Provider tells us that you're not using the TCP/IP protocol when you're trying to establish the connection. Try adding the "tcp" prefix and specifying the port number:

tcp:name.cloudapp.net,1433

How to delete only the content of file in python

I think the easiest is to simply open the file in write mode and then close it. For example, if your file myfile.dat contains:

"This is the original content"

Then you can simply write:

f = open('myfile.dat', 'w')
f.close()

This would erase all the content. Then you can write the new content to the file:

f = open('myfile.dat', 'w')
f.write('This is the new content!')
f.close()

Retrieve the maximum length of a VARCHAR column in SQL Server

Gives the Max Count of record in table

select max(len(Description))from Table_Name

Gives Record Having Greater Count

select Description from Table_Name group by Description having max(len(Description)) >27

Hope helps someone.

Using PropertyInfo.GetValue()

In your example propertyInfo.GetValue(this, null) should work. Consider altering GetNamesAndTypesAndValues() as follows:

public void GetNamesAndTypesAndValues()
{
  foreach (PropertyInfo propertyInfo in allClassProperties)
  {
    Console.WriteLine("{0} [type = {1}] [value = {2}]",
      propertyInfo.Name,
      propertyInfo.PropertyType,
      propertyInfo.GetValue(this, null));
  }
}

How to rename with prefix/suffix?

You can achieve a unix compatible multiple file rename (using wildcards) by creating a for loop:

for file in *; do
  mv $file new.${file%%}
done

How are parameters sent in an HTTP POST request?

Short answer: in POST requests, values are sent in the "body" of the request. With web-forms they are most likely sent with a media type of application/x-www-form-urlencoded or multipart/form-data. Programming languages or frameworks which have been designed to handle web-requests usually do "The Right Thing™" with such requests and provide you with easy access to the readily decoded values (like $_REQUEST or $_POST in PHP, or cgi.FieldStorage(), flask.request.form in Python).

Now let's digress a bit, which may help understand the difference ;)

The difference between GET and POST requests are largely semantic. They are also "used" differently, which explains the difference in how values are passed.

GET (relevant RFC section)

When executing a GET request, you ask the server for one, or a set of entities. To allow the client to filter the result, it can use the so called "query string" of the URL. The query string is the part after the ?. This is part of the URI syntax.

So, from the point of view of your application code (the part which receives the request), you will need to inspect the URI query part to gain access to these values.

Note that the keys and values are part of the URI. Browsers may impose a limit on URI length. The HTTP standard states that there is no limit. But at the time of this writing, most browsers do limit the URIs (I don't have specific values). GET requests should never be used to submit new information to the server. Especially not larger documents. That's where you should use POST or PUT.

POST (relevant RFC section)

When executing a POST request, the client is actually submitting a new document to the remote host. So, a query string does not (semantically) make sense. Which is why you don't have access to them in your application code.

POST is a little bit more complex (and way more flexible):

When receiving a POST request, you should always expect a "payload", or, in HTTP terms: a message body. The message body in itself is pretty useless, as there is no standard (as far as I can tell. Maybe application/octet-stream?) format. The body format is defined by the Content-Type header. When using a HTML FORM element with method="POST", this is usually application/x-www-form-urlencoded. Another very common type is multipart/form-data if you use file uploads. But it could be anything, ranging from text/plain, over application/json or even a custom application/octet-stream.

In any case, if a POST request is made with a Content-Type which cannot be handled by the application, it should return a 415 status-code.

Most programming languages (and/or web-frameworks) offer a way to de/encode the message body from/to the most common types (like application/x-www-form-urlencoded, multipart/form-data or application/json). So that's easy. Custom types require potentially a bit more work.

Using a standard HTML form encoded document as example, the application should perform the following steps:

Read the Content-Type field
If the value is not one of the supported media-types, then return a response with a 415 status code
otherwise, decode the values from the message body.

Again, languages like PHP, or web-frameworks for other popular languages will probably handle this for you. The exception to this is the 415 error. No framework can predict which content-types your application chooses to support and/or not support. This is up to you.

PUT (relevant RFC section)

A PUT request is pretty much handled in the exact same way as a POST request. The big difference is that a POST request is supposed to let the server decide how to (and if at all) create a new resource. Historically (from the now obsolete RFC2616 it was to create a new resource as a "subordinate" (child) of the URI where the request was sent to).

A PUT request in contrast is supposed to "deposit" a resource exactly at that URI, and with exactly that content. No more, no less. The idea is that the client is responsible to craft the complete resource before "PUTting" it. The server should accept it as-is on the given URL.

As a consequence, a POST request is usually not used to replace an existing resource. A PUT request can do both create and replace.

Side-Note

There are also "path parameters" which can be used to send additional data to the remote, but they are so uncommon, that I won't go into too much detail here. But, for reference, here is an excerpt from the RFC:

Aside from dot-segments in hierarchical paths, a path segment is considered opaque by the generic syntax. URI producing applications often use the reserved characters allowed in a segment to delimit scheme-specific or dereference-handler-specific subcomponents. For example, the semicolon (";") and equals ("=") reserved characters are often used to delimit parameters and parameter values applicable to that segment. The comma (",") reserved character is often used for similar purposes. For example, one URI producer might use a segment such as "name;v=1.1" to indicate a reference to version 1.1 of "name", whereas another might use a segment such as "name,1.1" to indicate the same. Parameter types may be defined by scheme-specific semantics, but in most cases the syntax of a parameter is specific to the implementation of the URIs dereferencing algorithm.

Fast ceiling of an integer division in C / C++

How about this? (requires y non-negative, so don't use this in the rare case where y is a variable with no non-negativity guarantee)

q = (x > 0)? 1 + (x - 1)/y: (x / y);

I reduced y/y to one, eliminating the term x + y - 1 and with it any chance of overflow.

I avoid x - 1 wrapping around when x is an unsigned type and contains zero.

For signed x, negative and zero still combine into a single case.

Probably not a huge benefit on a modern general-purpose CPU, but this would be far faster in an embedded system than any of the other correct answers.

How to change package name in flutter?

This is how i renamed package for both ios and android

Go to build.gradle in app module and rename applicationId "com.company.name"
Go to Manifest.xml in app/src/main and rename package="com.company.name" and android:label="App Name"
Go to Manifest.xml in app/src/debug and rename package="com.company.name"
Go to Manifest.xml in app/src/profile and rename package="com.company.name"
Go to app/src/main/kotlin/com/something/something/MainActivity.kt and rename package="com.company.name"
Go to app/src/main/kotlin/ and rename each directory so that the structure looks like app/src/main/kotlin/com/company/name/
Go to pubspec.yaml in your project and change name: something to name: name, example :- if package name is com.abc.xyz the name: xyz
Go to each dart file in lib folder and rename the imports to the modified name.
Open XCode and open the runner file and click on Runner in project explorer.
Go to General -> double click on Bundle Identifier -> rename it to com.company.name
Go to Info.plist click on Bundle name -> rename it to your App Name.
close everything -> go to your flutter project and run this command in terminal flutter clean

org.xml.sax.SAXParseException: Premature end of file for VALID XML

Are you sure that the XML file is in the correct character encoding? FileReader always uses the platform default encoding, so if the "working" server had a default encoding of (say) ISO-8859-1 and the "problem" server uses UTF-8 you would see this error if the XML contains any non-ASCII characters.

Does it work if you create the InputSource from a FileInputStream instead of a FileReader?

How can I set a cookie in react?

A very simple solution is using the sfcookies package. You just have to install it using npm for example: npm install sfcookies --save

Then you import on the file:

import { bake_cookie, read_cookie, delete_cookie } from 'sfcookies';

create a cookie key:

const cookie_key = 'namedOFCookie';

on your submit function, you create the cookie by saving data on it just like this:

bake_cookie(cookie_key, 'test');

to delete it just do

delete_cookie(cookie_key);

and to read it:

read_cookie(cookie_key)

Simple and easy to use.

Return file in ASP.Net Core Web API

You can return FileResult with this methods:

1: Return FileStreamResult

    [HttpGet("get-file-stream/{id}"]
    public async Task<FileStreamResult> DownloadAsync(string id)
    {
        var fileName="myfileName.txt";
        var mimeType="application/...."; 
        var stream = await GetFileStreamById(id);

        return new FileStreamResult(stream, mimeType)
        {
            FileDownloadName = fileName
        };
    }

2: Return FileContentResult

    [HttpGet("get-file-content/{id}"]
    public async Task<FileContentResult> DownloadAsync(string id)
    {
        var fileName="myfileName.txt";
        var mimeType="application/...."; 
        var fileBytes = await GetFileBytesById(id);

        return new FileContentResult(fileBytes, mimeType)
        {
            FileDownloadName = fileName
        };
    }

Java - get pixel array from image

This worked for me:

BufferedImage bufImgs = ImageIO.read(new File("c:\\adi.bmp"));    
double[][] data = new double[][];
bufImgs.getData().getPixels(0,0,bufImgs.getWidth(),bufImgs.getHeight(),data[i]);

What are static factory methods?

have names, unlike constructors, which can clarify code.

do not need to create a new object upon each invocation - objects can be cached and reused, if necessary.

can return a subtype of their return type - in particular, can return an object whose implementation class is unknown to the caller. This is a very valuable and widely used feature in many frameworks which use interfaces as the return type of static factory methods.

fromhttp://www.javapractices.com/topic/TopicAction.do?Id=21

Get current cursor position in a textbox

It looks OK apart from the space in your ID attribute, which is not valid, and the fact that you're replacing the value of your input before checking the selection.

_x000D_

function textbox()_x000D_
{_x000D_
        var ctl = document.getElementById('Javascript_example');_x000D_
        var startPos = ctl.selectionStart;_x000D_
        var endPos = ctl.selectionEnd;_x000D_
        alert(startPos + ", " + endPos);_x000D_
}

_x000D_

<input id="Javascript_example" name="one" type="text" value="Javascript example" onclick="textbox()">

_x000D_

Also, if you're supporting IE <= 8 you need to be aware that those browsers do not support selectionStart and selectionEnd.

Websocket onerror - how to read error description?

The error Event the onerror handler receives is a simple event not containing such information:

If the user agent was required to fail the WebSocket connection or the WebSocket connection is closed with prejudice, fire a simple event named error at the WebSocket object.

You may have better luck listening for the close event, which is a CloseEvent and indeed has a CloseEvent.code property containing a numerical code according to RFC 6455 11.7 and a CloseEvent.reason string property.

Please note however, that CloseEvent.code (and CloseEvent.reason) are limited in such a way that network probing and other security issues are avoided.

Speed tradeoff of Java's -Xms and -Xmx options

It is difficult to say how the memory allocation will affect your speed. It depends on the garbage collection algorithm the JVM is using. For example if your garbage collector needs to pause to do a full collection, then if you have 10 more memory than you really need then the collector will have 10 more garbage to clean up.

If you are using java 6 you can use the jconsole (in the bin directory of the jdk) to attach to your process and watch how the collector is behaving. In general the collectors are very smart and you won't need to do any tuning, but if you have a need there are numerous options you have use to further tune the collection process.

How to select a record and update it, with a single queryset in Django?

If you need to set the new value based on the old field value that is do something like:

update my_table set field_1 = field_1 + 1 where pk_field = some_value

use query expressions:

MyModel.objects.filter(pk=some_value).update(field1=F('field1') + 1)

This will execute update atomically that is using one update request to the database without reading it first.

Is the sizeof(some pointer) always equal to four?

In addition to the 16/32/64 bit differences even odder things can occur.

There have been machines where sizeof(int *) will be one value, probably 4 but where sizeof(char *) is larger. Machines that naturally address words instead of bytes have to "augment" character pointers to specify what portion of the word you really want in order to properly implement the C/C++ standard.

This is now very unusual as hardware designers have learned the value of byte addressability.

How to render html with AngularJS templates

Use-

<span ng-bind-html="myContent"></span>

You need to tell angular to not escape it.

Node.js get file extension

You can use path.parse(path), for example

const path = require('path');
const { ext } = path.parse('/home/user/dir/file.txt');

Static class initializer in PHP

Note - the RFC proposing this is still in the draft state.

class Singleton
{
    private static function __static()
    {
        //...
    }
    //...
}

proposed for PHP 7.x (see https://wiki.php.net/rfc/static_class_constructor )

Shell equality operators (=, ==, -eq)

It depends on the Test Construct around the operator. Your options are double parentheses, double brackets, single brackets, or test.

If you use ((…)), you are testing arithmetic equality with == as in C:

$ (( 1==1 )); echo $?
0
$ (( 1==2 )); echo $?
1

(Note: 0 means true in the Unix sense and a failed test results in a non-zero number.)

Using -eq inside of double parentheses is a syntax error.

If you are using […] (or single brackets) or [[…]] (or double brackets), or test you can use one of -eq, -ne, -lt, -le, -gt, or -ge as an arithmetic comparison.

$ [ 1 -eq 1 ]; echo $?
0
$ [ 1 -eq 2 ]; echo $?
1
$ test 1 -eq 1; echo $?
0

The == inside of single or double brackets (or the test command) is one of the string comparison operators:

$ [[ "abc" == "abc" ]]; echo $?
0
$ [[ "abc" == "ABC" ]]; echo $?
1

As a string operator, = is equivalent to ==. Also, note the whitespace around = or ==: it’s required.

While you can do [[ 1 == 1 ]] or [[ $(( 1+1 )) == 2 ]] it is testing the string equality — not the arithmetic equality.

So -eq produces the result probably expected that the integer value of 1+1 is equal to 2 even though the right-hand side is a string and has a trailing space:

$ [[ $(( 1+1 )) -eq  "2 " ]]; echo $?
0

While a string comparison of the same picks up the trailing space and therefore the string comparison fails:

$ [[ $(( 1+1 )) == "2 " ]]; echo $?
1

And a mistaken string comparison can produce a completely wrong answer. 10 is lexicographically less than 2, so a string comparison returns true or 0. So many are bitten by this bug:

$ [[ 10 < 2 ]]; echo $?
0

The correct test for 10 being arithmetically less than 2 is this:

$ [[ 10 -lt 2 ]]; echo $?
1

In comments, there is a question about the technical reason why using the integer -eq on strings returns true for strings that are not the same:

$ [[ "yes" -eq "no" ]]; echo $?
0

The reason is that Bash is untyped. The -eq causes the strings to be interpreted as integers if possible including base conversion:

$ [[ "0x10" -eq 16 ]]; echo $?
0
$ [[ "010" -eq 8 ]]; echo $?
0
$ [[ "100" -eq 100 ]]; echo $?
0

And 0 if Bash thinks it is just a string:

$ [[ "yes" -eq 0 ]]; echo $?
0
$ [[ "yes" -eq 1 ]]; echo $?
1

So [[ "yes" -eq "no" ]] is equivalent to [[ 0 -eq 0 ]]

Last note: Many of the Bash specific extensions to the Test Constructs are not POSIX and therefore may fail in other shells. Other shells generally do not support [[...]] and ((...)) or ==.

Asp.net Validation of viewstate MAC failed

WHAT DID WORK FOR ME

Search the web for "MachineKey generator"
Go to one of the sites found and generate the Machine Key, that will look like... (the numbers are bigger)
...MachineKey
validationKey="0EF6C03C11FC...63EAE6A00F0B6B35DD4B" decryptionKey="2F5E2FD80991C629...3ACA674CD3B5F068" validation="SHA1" decryption="AES" />
Copy and paste into the <system.web> section in the web.config file.

If you want to follow the path I did...

https://support.microsoft.com/en-us/kb/2915218#AppendixA
Resolving view state message authentication code (MAC) errors Resolution 3b: Use an explicit <machineKey>
By adding an explicit <machineKey> element to the application's Web.config file, the developer tells ASP.NET not to use the auto-generated cryptographic key. See Appendix A for instructions on how to generate a <machineKey> element.

http://blogs.msdn.com/b/amb/archive/2012/07/31/easiest-way-to-generate-machinekey.aspx
Easiest way to generate MachineKey - Ahmet Mithat Bostanci - 31 Jul 2012 You can search in Bing for "MachineKey generator" and use an online service. Honestly...

http://www.blackbeltcoder.com/Resources/MachineKey.aspx

How to execute XPath one-liners from shell?

Saxon will do this not only for XPath 2.0, but also for XQuery 1.0 and (in the commercial version) 3.0. It doesn't come as a Linux package, but as a jar file. Syntax (which you can easily wrap in a simple script) is

java net.sf.saxon.Query -s:source.xml -qs://element/attribute

2020 UPDATE

Saxon 10.0 includes the Gizmo tool, which can be used interactively or in batch from the command line. For example

java net.sf.saxon.Gizmo -s:source.xml
/>show //element/@attribute
/>quit

In MVC, how do I return a string result?

There Are 2 ways to return a string from the controller to the view:

First

You could return only the string, but it will not be included in your .cshtml file. it will be just a string appearing in your browser.

Second

You could return a string as the Model object of View Result.

Here is the code sample to do this:

public class HomeController : Controller
{
    // GET: Home
    // this will return just a string, not html
    public string index()
    {
        return "URL to show";
    }

    public ViewResult AutoProperty()
    {   
        string s = "this is a string ";
        // name of view , object you will pass
        return View("Result", s);

    }
}

In the view file to run AutoProperty, It will redirect you to the Result view and will send s
code to the view

<!--this will make this file accept string as it's model-->
@model string

@{
    Layout = null;
}

<!DOCTYPE html>

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Result</title>
</head>
<body>
    <!--this will represent the string -->
    @Model
</body>
</html>

I run this at http://localhost:60227/Home/AutoProperty.

ConcurrentModificationException for ArrayList

You can't remove from list if you're browsing it with "for each" loop. You can use Iterator. Replace:

for (DrugStrength aDrugStrength : aDrugStrengthList) {
    if (!aDrugStrength.isValidDrugDescription()) {
        aDrugStrengthList.remove(aDrugStrength);
    }
}

With:

for (Iterator<DrugStrength> it = aDrugStrengthList.iterator(); it.hasNext(); ) {
    DrugStrength aDrugStrength = it.next();
    if (!aDrugStrength.isValidDrugDescription()) {
        it.remove();
    }
}

Vibrate and Sound defaults on notification

// set notification audio

builder.setDefaults(Notification.DEFAULT_VIBRATE);
//OR 
builder.setDefaults(Notification.DEFAULT_SOUND);

How do I install imagemagick with homebrew?

You could do:

brew reinstall php55-imagick

Where php55 is your PHP version.

How to tell if a <script> tag failed to load

This can be done safely using promises

    function loadScript(src) {
      return new Promise(function(resolve, reject) {
        let script = document.createElement('script');
        script.src = src;
    
        script.onload = () => resolve(script);
        script.onerror = () => reject(new Error("Script load error: " + src));
    
        document.head.append(script);
      });
    }

and use like this

    let promise = loadScript("https://cdnjs.cloudflare.com/ajax/libs/lodash.js/3.2.0/lodash.js");
    
    promise.then(
      script => alert(`${script.src} is loaded!`),
      error => alert(`Error: ${error.message}`)
    );

Force browser to download image files on click

Using HTML5 you can add the attribute 'download' to your links.

<a href="/path/to/image.png" download>

Compliant browsers will then prompt to download the image with the same file name (in this example image.png).

If you specify a value for this attribute, then that will become the new filename:

<a href="/path/to/image.png" download="AwesomeImage.png">

UPDATE: As of spring 2018 this is no longer possible for cross-origin hrefs. So if you want to create <a href="https://i.imgur.com/IskAzqA.jpg" download> on a domain other than imgur.com it will not work as intended. Chrome deprecations and removals announcement

How to limit the maximum files chosen when using multiple file input

In javascript you can do something like this

<input
  ref="fileInput"
  multiple
  type="file"
  style="display: none"
  @change="trySubmitFile"
>

and the function can be something like this.

trySubmitFile(e) {
  if (this.disabled) return;
  const files = e.target.files || e.dataTransfer.files;
  if (files.length > 5) {
    alert('You are only allowed to upload a maximum of 2 files at a time');
  }
  if (!files.length) return;
  for (let i = 0; i < Math.min(files.length, 2); i++) {
    this.fileCallback(files[i]);
  }
}

I am also searching for a solution where this can be limited at the time of selecting files but until now I could not find anything like that.

How do I move a file from one location to another in Java?

You can try this.. clean solution

Files.move(source, target, REPLACE_EXISTING);

How can I display just a portion of an image in HTML/CSS?

As mentioned in the question, there is the clip css property, although it does require that the element being clipped is position: absolute; (which is a shame):

_x000D_

.container {_x000D_
  position: relative;_x000D_
}_x000D_
#clip {_x000D_
  position: absolute;_x000D_
  clip: rect(0, 100px, 200px, 0);_x000D_
  /* clip: shape(top, right, bottom, left); NB 'rect' is the only available option */_x000D_
}

_x000D_

<div class="container">_x000D_
  <img src="http://lorempixel.com/200/200/nightlife/3" />_x000D_
</div>_x000D_
<div class="container">_x000D_
  <img id="clip" src="http://lorempixel.com/200/200/nightlife/3" />_x000D_
</div>

_x000D_

JS Fiddle demo, for experimentation.

To supplement the original answer – somewhat belatedly – I'm editing to show the use of clip-path, which has replaced the now-deprecated clip property.

The clip-path property allows a range of options (more-so than the original clip), of:

inset — rectangular/cuboid shapes, defined with four values as 'distance-from' (top right bottom left).
circle — circle(diameter at x-coordinate y-coordinate).
ellipse — ellipse(x-axis-length y-axis-length at x-coordinate y-coordinate).
polygon — defined by a series of x/y coordinates in relation to the element's origin of the top-left corner. As the path is closed automatically the realistic minimum number of points for a polygon should be three, any fewer (two) is a line or (one) is a point: polygon(x-coordinate1 y-coordinate1, x-coordinate2 y-coordinate2, x-coordinate3 y-coordinate3, [etc...]).
url — this can be either a local URL (using a CSS id-selector) or the URL of an external file (using a file-path) to identify an SVG, though I've not experimented with either (as yet), so I can offer no insight as to their benefit or caveat.

_x000D_

div.container {_x000D_
  display: inline-block;_x000D_
}_x000D_
#rectangular {_x000D_
  -webkit-clip-path: inset(30px 10px 30px 10px);_x000D_
  clip-path: inset(30px 10px 30px 10px);_x000D_
}_x000D_
#circle {_x000D_
  -webkit-clip-path: circle(75px at 50% 50%);_x000D_
  clip-path: circle(75px at 50% 50%)_x000D_
}_x000D_
#ellipse {_x000D_
  -webkit-clip-path: ellipse(75px 50px at 50% 50%);_x000D_
  clip-path: ellipse(75px 50px at 50% 50%);_x000D_
}_x000D_
#polygon {_x000D_
  -webkit-clip-path: polygon(50% 0, 100% 38%, 81% 100%, 19% 100%, 0 38%);_x000D_
  clip-path: polygon(50% 0, 100% 38%, 81% 100%, 19% 100%, 0 38%);_x000D_
}

_x000D_

<div class="container">_x000D_
  <img id="control" src="http://lorempixel.com/150/150/people/1" />_x000D_
</div>_x000D_
<div class="container">_x000D_
  <img id="rectangular" src="http://lorempixel.com/150/150/people/1" />_x000D_
</div>_x000D_
<div class="container">_x000D_
  <img id="circle" src="http://lorempixel.com/150/150/people/1" />_x000D_
</div>_x000D_
<div class="container">_x000D_
  <img id="ellipse" src="http://lorempixel.com/150/150/people/1" />_x000D_
</div>_x000D_
<div class="container">_x000D_
  <img id="polygon" src="http://lorempixel.com/150/150/people/1" />_x000D_
</div>

_x000D_

JS Fiddle demo, for experimentation.

References:

~~clip~~ — note: deprecated.
clip-path (MDN).
clip-path (W3C).

Initialize class fields in constructor or at declaration?

There are many and various situations.

I just need an empty list

The situation is clear. I just need to prepare my list and prevent an exception from being thrown when someone adds an item to the list.

public class CsvFile
{
    private List<CsvRow> lines = new List<CsvRow>();

    public CsvFile()
    {
    }
}

I know the values

I exactly know what values I want to have by default or I need to use some other logic.

public class AdminTeam
{
    private List<string> usernames;

    public AdminTeam()
    {
         usernames = new List<string>() {"usernameA", "usernameB"};
    }
}

public class AdminTeam
{
    private List<string> usernames;

    public AdminTeam()
    {
         usernames = GetDefaultUsers(2);
    }
}

Empty list with possible values

Sometimes I expect an empty list by default with a possibility of adding values through another constructor.

public class AdminTeam
{
    private List<string> usernames = new List<string>();

    public AdminTeam()
    {
    }

    public AdminTeam(List<string> admins)
    {
         admins.ForEach(x => usernames.Add(x));
    }
}

Factorial using Recursion in Java

What happens is that the recursive call itself results in further recursive behaviour. If you were to write it out you get:

 fact(4)
 fact(3) * 4;
 (fact(2) * 3) * 4;
 ((fact(1) * 2) * 3) * 4;
 ((1 * 2) * 3) * 4;

How to get the SHA-1 fingerprint certificate in Android Studio for debug mode?

When creating a new "Google Maps Project", in Android Studio V 1.5.1, the last screen opens the google_maps_api.xml file and displays the screen with instructions as follows:

Resources:

TODO: Before you run your application, you need a Google Maps API key.

To get one, follow this link, follow the directions and press "Create" at the end:

https://console.developers.google.com/flows/enableapi?apiid=maps_android_backend&keyType=CLIENT_SIDE_ANDROID&r= YOUR SHA-1 + YOUR PACKAGE NAME

You can also add your credentials to an existing key, using this line:
YOUR SHA-1:YOUR PACKAGE NAME

Alternatively, follow the directions here:
https://developers.google.com/maps/documentation/android/start#get-key

Once you have your key (it starts with "AIza"), replace the "google_maps_key" string in this file.
<string name="google_maps_key" templateMergeStrategy="preserve" translatable="false">YOUR GOOGLE MAPS KEY</string>

To get YOUR GOOGLE MAPS KEY just cut and paste the URL link given into your browser and follow the instructions above at the time of creating the new application. The SHA-1 and Package names are already in the link given so you do not need to know them. They will however be in your project in the resources>Values>google_maps_api.xml file which is completed when you follow the instructions on creating the project.

How to define custom configuration variables in rails

In Rails 3, Application specific custom configuration data can be placed in the application configuration object. The configuration can be assigned in the initialization files or the environment files -- say for a given application MyApp:

MyApp::Application.config.custom_config_variable = :my_config_setting

Rails.configuration.custom_config_variable = :my_config_setting

To read the setting, simply call the configuration variable without setting it:

Rails.configuration.custom_config_variable
=> :my_config_setting

UPDATE Rails 4

In Rails 4 there a new way for this => http://guides.rubyonrails.org/configuring.html#custom-configuration

enter image description here

Get img src with PHP

$imgTag = <<< LOB
<img border="0" src="/images/image.jpg" alt="Image" width="100" height="100" />
<img border="0" src="/images/not_match_image.jpg" alt="Image" width="100" height="100" />
LOB;

preg_match('%<img.*?src=["\'](.*?)["\'].*?/>%i', $imgTag, $matches);
$imgSrc = $matches[1];

DEMO

NOTE: You should use an HTML Parser like DOMDocument and NOT a regex.

C# send a simple SSH command

SharpSSH should do the job. http://www.codeproject.com/Articles/11966/sharpSsh-A-Secure-Shell-SSH-library-for-NET

Displaying a message in iOS which has the same functionality as Toast in Android

If you want pure swift, we released our internal file. It's pretty simple

https://github.com/gglresearchanddevelopment/ios-toast

Convert factor to integer

You can combine the two functions; coerce to characters thence to numerics:

> fac <- factor(c("1","2","1","2"))
> as.numeric(as.character(fac))
[1] 1 2 1 2

Sending XML data using HTTP POST with PHP

you can use cURL library for posting data: http://www.php.net/curl

$ch = curl_init();
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER,1);
curl_setopt($ch, CURLOPT_URL, "http://websiteURL");
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, "XML=".$xmlcontent."&password=".$password."&etc=etc");
$content=curl_exec($ch);

where postfield contains XML you need to send - you will need to name the postfield the API service (Clickatell I guess) expects

Search for highest key/index in an array

Try max(): http://php.net/manual/en/function.max.php See the first comment on that page

Looping through a hash, or using an array in PowerShell

If you're using PowerShell v3, you can use JSON instead of a hashtable, and convert it to an object with Convert-FromJson:

@'
[
    {
        FileName = "Page";
        ObjectName = "vExtractPage";
    },
    {
        ObjectName = "ChecklistItemCategory";
    },
    {
        ObjectName = "ChecklistItem";
    },
]
'@ | 
    Convert-FromJson |
    ForEach-Object {
        $InputFullTableName = '{0}{1}' -f $TargetDatabase,$_.ObjectName

        # In strict mode, you can't reference a property that doesn't exist, 
        #so check if it has an explicit filename firest.
        $outputFileName = $_.ObjectName
        if( $_ | Get-Member FileName )
        {
            $outputFileName = $_.FileName
        }
        $OutputFullFileName = Join-Path $OutputDirectory $outputFileName

        bcp $InputFullTableName out $OutputFullFileName -T -c $ServerOption
    }

Get top 1 row of each group

I've done some timings over the various recommendations here, and the results really depend on the size of the table involved, but the most consistent solution is using the CROSS APPLY These tests were run against SQL Server 2008-R2, using a table with 6,500 records, and another (identical schema) with 137 million records. The columns being queried are part of the primary key on the table, and the table width is very small (about 30 bytes). The times are reported by SQL Server from the actual execution plan.

Query                                  Time for 6500 (ms)    Time for 137M(ms)

CROSS APPLY                                    17.9                17.9
SELECT WHERE col = (SELECT MAX(COL)…)           6.6               854.4
DENSE_RANK() OVER PARTITION                     6.6               907.1

I think the really amazing thing was how consistent the time was for the CROSS APPLY regardless of the number of rows involved.

PostgreSQL how to see which queries have run

PostgreSql is very advanced when related to logging techniques

Logs are stored in Installationfolder/data/pg_log folder. While log settings are placed in postgresql.conf file.

Log format is usually set as stderr. But CSV log format is recommended. In order to enable CSV format change in

log_destination = 'stderr,csvlog'   
logging_collector = on

In order to log all queries, very usefull for new installations, set min. execution time for a query

log_min_duration_statement = 0

In order to view active Queries on your database, use

SELECT * FROM pg_stat_activity

To log specific queries set query type

log_statement = 'all'           # none, ddl, mod, all

For more information on Logging queries see PostgreSql Log.

How do I get interactive plots again in Spyder/IPython/matplotlib?

Change the backend to automatic:

Tools > preferences > IPython console > Graphics > Graphics backend > Backend: Automatic

Then close and open Spyder.

Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?

@article = user.articles.build(:title => "MainTitle")
@article.save

List of Python format characters

It's the first result on Google: http://docs.python.org/library/stdtypes.html#string-formatting

See also the new format() function: http://docs.python.org/library/stdtypes.html#str.format

Where Sticky Notes are saved in Windows 10 1607

Use this document to transfer Sticky Notes data file StickyNotes.snt to the new format

http://www.winhelponline.com/blog/recover-backup-sticky-notes-data-file-windows-10/

Restore:

%LocalAppData%\Packages\Microsoft.MicrosoftStickyNotes_8wekyb3d8bbwe\LocalState

Close Sticky Notes
Create a new folder named Legacy
Under the Legacy folder, copy your existing StickyNotes.snt, and rename it to ThresholdNotes.snt
Start the Sticky Notes app. It reads the legacy .snt file and transfers the content to the database file automatically.

Backup

just backup following file.

%LocalAppData%\Packages\Microsoft.MicrosoftStickyNotes_8wekyb3d8bbwe\LocalState\plum.sqlite

How to set the timeout for a TcpClient?

The answers above don't cover how to cleanly deal with a connection that has timed out. Calling TcpClient.EndConnect, closing a connection that succeeds but after the timeout, and disposing of the TcpClient.

It may be overkill but this works for me.

    private class State
    {
        public TcpClient Client { get; set; }
        public bool Success { get; set; }
    }

    public TcpClient Connect(string hostName, int port, int timeout)
    {
        var client = new TcpClient();

        //when the connection completes before the timeout it will cause a race
        //we want EndConnect to always treat the connection as successful if it wins
        var state = new State { Client = client, Success = true };

        IAsyncResult ar = client.BeginConnect(hostName, port, EndConnect, state);
        state.Success = ar.AsyncWaitHandle.WaitOne(timeout, false);

        if (!state.Success || !client.Connected)
            throw new Exception("Failed to connect.");

        return client;
    }

    void EndConnect(IAsyncResult ar)
    {
        var state = (State)ar.AsyncState;
        TcpClient client = state.Client;

        try
        {
            client.EndConnect(ar);
        }
        catch { }

        if (client.Connected && state.Success)
            return;

        client.Close();
    }

How to input matrix (2D list) in Python?

a = []
b = []

m=input("enter no of rows: ")
n=input("enter no of coloumns: ")

for i in range(n):
     a = []
     for j in range(m):
         a.append(input())
     b.append(a)

Input : 1 2 3 4 5 6 7 8 9

Output : [ ['1', '2', '3'], ['4', '5', '6'], ['7', '8', '9'] ]

How to Copy Contents of One Canvas to Another Canvas Locally

Actually you don't have to create an image at all. drawImage() will accept a Canvas as well as an Image object.

//grab the context from your destination canvas
var destCtx = destinationCanvas.getContext('2d');

//call its drawImage() function passing it the source canvas directly
destCtx.drawImage(sourceCanvas, 0, 0);

Way faster than using an ImageData object or Image element.

Note that sourceCanvas can be a HTMLImageElement, HTMLVideoElement, or a HTMLCanvasElement. As mentioned by Dave in a comment below this answer, you cannot use a canvas drawing context as your source. If you have a canvas drawing context instead of the canvas element it was created from, there is a reference to the original canvas element on the context under context.canvas.

Here is a jsPerf to demonstrate why this is the only right way to clone a canvas: http://jsperf.com/copying-a-canvas-element

UITableView set to static cells. Is it possible to hide some of the cells programmatically?

The best way is as described in the following blog http://ali-reynolds.com/2013/06/29/hide-cells-in-static-table-view/

Design your static table view as normal in interface builder – complete with all potentially hidden cells. But there is one thing you must do for every potential cell that you want to hide – check the “Clip subviews” property of the cell, otherwise the content of the cell doesn’t disappear when you try and hide it (by shrinking it’s height – more later).

SO – you have a switch in a cell and the switch is supposed to hide and show some static cells. Hook it up to an IBAction and in there do this:
[self.tableView beginUpdates];
[self.tableView endUpdates];
That gives you nice animations for the cells appearing and disappearing. Now implement the following table view delegate method:
- (float)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    if (indexPath.section == 1 && indexPath.row == 1) { // This is the cell to hide - change as you need
    // Show or hide cell
        if (self.mySwitch.on) {
            return 44; // Show the cell - adjust the height as you need
        } else {
            return 0; // Hide the cell
        }
   }
   return 44;
}
And that’s it. Flip the switch and the cell hides and reappears with a nice, smooth animation.

Error Code: 2013. Lost connection to MySQL server during query

This happened to me because my innodb_buffer_pool_size was set to be larger than the RAM size available on the server. Things were getting interrupted because of this and it issues this error. The fix is to update my.cnf with the correct setting for innodb_buffer_pool_size.

How to get request url in a jQuery $.get/ajax request

I can't get it to work on $.get() because it has no complete event.

I suggest to use $.ajax() like this,

$.ajax({
    url: 'http://www.example.org',
    data: {'a':1,'b':2,'c':3},
    dataType: 'xml',
    complete : function(){
        alert(this.url)
    },
    success: function(xml){
    }
});

craz demo

error opening trace file: No such file or directory (2)

Write all your code below this 2 lines:-

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

It worked for me without re-installing again.

How to clear browsing history using JavaScript?

Can you try using document.location.replace() it is used to clear the last entry in the history and replace it with the address of a new url. replace() removes the URL of the current document from the document history, meaning that it is not possible to use the "back" button to navigate back to the original document.

<script type="text/javascript">
    function Navigate(){   
         window.location.replace('your link');
        return false;
    }
   </script>

HTML:

   <button onclick="Navigate()">Replace document</button>

How to Import .bson file format on mongodb

You have to run this mongorestore command via cmd and not on Mongo Shell... Have a look at below command on...

Run this command on cmd (not on Mongo shell)

>path\to\mongorestore.exe -d dbname -c collection_name path\to\same\collection.bson

Here path\to\mongorestore.exe is path of mongorestore.exe inside bin folder of mongodb. dbname is name of databse. collection_name is name of collection.bson. path\to\same\collection.bson is the path up to that collection.

Now from mongo shell you can verify that database is created or not (If it does not exist, database with same name will be created with collection).

How might I extract the property values of a JavaScript object into an array?

I prefer to destruct object values into array:

[...Object.values(dataObject)]

var dataObject = {
   object1: {id: 1, name: "Fred"}, 
   object2: {id: 2, name: "Wilma"}, 
   object3: {id: 3, name: "Pebbles"}
};

var dataArray = [...Object.values(dataObject)];

How to build x86 and/or x64 on Windows from command line with CMAKE?

This cannot be done with CMake. You have to generate two separate build folders. One for the x86 NMake build and one for the x64 NMake build. You cannot generate a single Visual Studio project covering both architectures with CMake, either.

To build Visual Studio projects from the command line for both 32-bit and 64-bit without starting a Visual Studio command prompt, use the regular Visual Studio generators.

For CMake 3.13 or newer, run the following commands:

cmake -G "Visual Studio 16 2019" -A Win32 -S \path_to_source\ -B "build32"
cmake -G "Visual Studio 16 2019" -A x64 -S \path_to_source\ -B "build64"
cmake --build build32 --config Release
cmake --build build64 --config Release

For earlier versions of CMake, run the following commands:

mkdir build32 & pushd build32
cmake -G "Visual Studio 15 2017" \path_to_source\
popd
mkdir build64 & pushd build64
cmake -G "Visual Studio 15 2017 Win64" \path_to_source\
popd
cmake --build build32 --config Release
cmake --build build64 --config Release

CMake generated projects that use one of the Visual Studio generators can be built from the command line with using the option --build followed by the build directory. The --config option specifies the build configuration.

How can I properly use a PDO object for a parameterized SELECT query

You can use the bindParam or bindValue methods to help prepare your statement. It makes things more clear on first sight instead of doing $check->execute(array(':name' => $name)); Especially if you are binding multiple values/variables.

Check the clear, easy to read example below:

$q = $db->prepare("SELECT id FROM table WHERE forename = :forename and surname = :surname LIMIT 1");
$q->bindValue(':forename', 'Joe');
$q->bindValue(':surname',  'Bloggs');
$q->execute();

if ($q->rowCount() > 0){
    $check = $q->fetch(PDO::FETCH_ASSOC);
    $row_id = $check['id'];
    // do something
}

If you are expecting multiple rows remove the LIMIT 1 and change the fetch method into fetchAll:

$q = $db->prepare("SELECT id FROM table WHERE forename = :forename and surname = :surname");// removed limit 1
$q->bindValue(':forename', 'Joe');
$q->bindValue(':surname',  'Bloggs');
$q->execute();

if ($q->rowCount() > 0){
    $check = $q->fetchAll(PDO::FETCH_ASSOC);
    //$check will now hold an array of returned rows. 
    //let's say we need the second result, i.e. index of 1
    $row_id = $check[1]['id']; 
    // do something
}

comparing strings in vb

I would suggest using the String.Compare method. Using that method you can also control whether to to have it perform case-sensitive comparisons or not.

Sample:

Dim str1 As String = "String one"
Dim str2 As String = str1
Dim str3 As String = "String three"
Dim str4 As String = str3

If String.Compare(str1, str2) = 0 And String.Compare(str3, str4) = 0 Then
    MessageBox.Show("str1 = str2 And str3 = str4")
Else
    MessageBox.Show("Else")
End If

Edit: if you want to perform a case-insensitive search you can use the StringComparison parameter:

If String.Compare(str1, str2, StringComparison.InvariantCultureIgnoreCase) = 0 And String.Compare(str3, str4, StringComparison.InvariantCultureIgnoreCase) = 0 Then

Numpy first occurrence of value greater than existing value

This is a little faster (and looks nicer)

np.argmax(aa>5)

Since argmax will stop at the first True ("In case of multiple occurrences of the maximum values, the indices corresponding to the first occurrence are returned.") and doesn't save another list.

In [2]: N = 10000

In [3]: aa = np.arange(-N,N)

In [4]: timeit np.argmax(aa>N/2)
100000 loops, best of 3: 52.3 us per loop

In [5]: timeit np.where(aa>N/2)[0][0]
10000 loops, best of 3: 141 us per loop

In [6]: timeit np.nonzero(aa>N/2)[0][0]
10000 loops, best of 3: 142 us per loop

Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_u64 on Intel CPUs

First of all, try to estimate peak performance - examine https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf, in particular, Appendix C.

In your case, it's table C-10 that shows POPCNT instruction has latency = 3 clocks and throughput = 1 clock. Throughput shows your maximal rate in clocks (multiply by core frequency and 8 bytes in case of popcnt64 to get your best possible bandwidth number).

Now examine what compiler did and sum up throughputs of all other instructions in the loop. This will give best possible estimate for generated code.

At last, look at data dependencies between instructions in the loop as they will force latency-large delay instead of throughput - so split instructions of single iteration on data flow chains and calculate latency across them then naively pick up maximal from them. it will give rough estimate taking into account data flow dependencies.

However, in your case, just writing code the right way would eliminate all these complexities. Instead of accumulating to the same count variable, just accumulate to different ones (like count0, count1, ... count8) and sum them up at the end. Or even create an array of counts[8] and accumulate to its elements - perhaps, it will be vectorized even and you will get much better throughput.

P.S. and never run benchmark for a second, first warm up the core then run loop for at least 10 seconds or better 100 seconds. otherwise, you will test power management firmware and DVFS implementation in hardware :)

P.P.S. I heard endless debates on how much time should benchmark really run. Most smartest folks are even asking why 10 seconds not 11 or 12. I should admit this is funny in theory. In practice, you just go and run benchmark hundred times in a row and record deviations. That IS funny. Most people do change source and run bench after that exactly ONCE to capture new performance record. Do the right things right.

Not convinced still? Just use above C-version of benchmark by assp1r1n3 (https://stackoverflow.com/a/37026212/9706746) and try 100 instead of 10000 in retry loop.

My 7960X shows, with RETRY=100:

Count: 203182300 Elapsed: 0.008385 seconds Speed: 12.505379 GB/s

Count: 203182300 Elapsed: 0.011063 seconds Speed: 9.478225 GB/s

Count: 203182300 Elapsed: 0.011188 seconds Speed: 9.372327 GB/s

Count: 203182300 Elapsed: 0.010393 seconds Speed: 10.089252 GB/s

Count: 203182300 Elapsed: 0.009076 seconds Speed: 11.553283 GB/s

with RETRY=10000:

Count: 20318230000 Elapsed: 0.661791 seconds Speed: 15.844519 GB/s

Count: 20318230000 Elapsed: 0.665422 seconds Speed: 15.758060 GB/s

Count: 20318230000 Elapsed: 0.660983 seconds Speed: 15.863888 GB/s

Count: 20318230000 Elapsed: 0.665337 seconds Speed: 15.760073 GB/s

Count: 20318230000 Elapsed: 0.662138 seconds Speed: 15.836215 GB/s

P.P.P.S. Finally, on "accepted answer" and other mistery ;-)

Let's use assp1r1n3's answer - he has 2.5Ghz core. POPCNT has 1 clock throuhgput, his code is using 64-bit popcnt. So math is 2.5Ghz * 1 clock * 8 bytes = 20 GB/s for his setup. He is seeing 25Gb/s, perhaps due to turbo boost to around 3Ghz.

Thus go to ark.intel.com and look for i7-4870HQ: https://ark.intel.com/products/83504/Intel-Core-i7-4870HQ-Processor-6M-Cache-up-to-3-70-GHz-?q=i7-4870HQ

That core could run up to 3.7Ghz and real maximal rate is 29.6 GB/s for his hardware. So where is another 4GB/s? Perhaps, it's spent on loop logic and other surrounding code within each iteration.

Now where is this false dependency? hardware runs at almost peak rate. Maybe my math is bad, it happens sometimes :)

P.P.P.P.P.S. Still people suggesting HW errata is culprit, so I follow suggestion and created inline asm example, see below.

On my 7960X, first version (with single output to cnt0) runs at 11MB/s, second version (with output to cnt0, cnt1, cnt2 and cnt3) runs at 33MB/s. And one could say - voila! it's output dependency.

OK, maybe, the point I made is that it does not make sense to write code like this and it's not output dependency problem but dumb code generation. We are not testing hardware, we are writing code to unleash maximal performance. You could expect that HW OOO should rename and hide those "output-dependencies" but, gash, just do the right things right and you will never face any mystery.

uint64_t builtin_popcnt1a(const uint64_t* buf, size_t len) 
{
    uint64_t cnt0, cnt1, cnt2, cnt3;
    cnt0 = cnt1 = cnt2 = cnt3 = 0;
    uint64_t val = buf[0];
    #if 0
        __asm__ __volatile__ (
            "1:\n\t"
            "popcnt %2, %1\n\t"
            "popcnt %2, %1\n\t"
            "popcnt %2, %1\n\t"
            "popcnt %2, %1\n\t"
            "subq $4, %0\n\t"
            "jnz 1b\n\t"
        : "+q" (len), "=q" (cnt0)
        : "q" (val)
        :
        );
    #else
        __asm__ __volatile__ (
            "1:\n\t"
            "popcnt %5, %1\n\t"
            "popcnt %5, %2\n\t"
            "popcnt %5, %3\n\t"
            "popcnt %5, %4\n\t"
            "subq $4, %0\n\t"
            "jnz 1b\n\t"
        : "+q" (len), "=q" (cnt0), "=q" (cnt1), "=q" (cnt2), "=q" (cnt3)
        : "q" (val)
        :
        );
    #endif
    return cnt0;
}

Handling Dialogs in WPF with MVVM

I think the view could have code to handle the event from the view model.

Depending on the event/scenario, it could also have an event trigger that subscribes to view model events, and one or more actions to invoke in response.

Using "Object.create" instead of "new"

Another possible usage of Object.create is to clone immutable objects in a cheap and effective way.

var anObj = {
    a: "test",
    b: "jest"
};

var bObj = Object.create(anObj);

bObj.b = "gone"; // replace an existing (by masking prototype)
bObj.c = "brand"; // add a new to demonstrate it is actually a new obj

// now bObj is {a: test, b: gone, c: brand}

Notes: The above snippet creates a clone of an source object (aka not a reference, as in cObj = aObj). It benefits over the copy-properties method (see 1), in that it does not copy object member properties. Rather it creates another -destination- object with it's prototype set on the source object. Moreover when properties are modified on the dest object, they are created "on the fly", masking the prototype's (src's) properties.This constitutes a fast an effective way of cloning immutable objects.

The caveat here is that this applies to source objects that should not be modified after creation (immutable). If the source object is modified after creation, all the clone's unmasked properties will be modified, too.

Fiddle here(http://jsfiddle.net/y5b5q/1/) (needs Object.create capable browser).

GridView VS GridLayout in Android Apps

A GridView is a ViewGroup that displays items in two-dimensional scrolling grid. The items in the grid come from the ListAdapter associated with this view.

This is what you'd want to use (keep using). Because a GridView gets its data from a ListAdapter, the only data loaded in memory will be the one displayed on screen. GridViews, much like ListViews reuse and recycle their views for better performance.

Whereas a GridLayout is a layout that places its children in a rectangular grid.

It was introduced in API level 14, and was recently backported in the Support Library. Its main purpose is to solve alignment and performance problems in other layouts. Check out this tutorial if you want to learn more about GridLayout.

Get the value of a dropdown in jQuery

$('#Crd').val() will give you the selected value of the drop down element. Use this to get the selected options text.

$('#Crd option:selected').text();

How to set a header in an HTTP response?

First of all you have to understand the nature of

response.sendRedirect(newUrl);

It is giving the client (browser) 302 http code response with an URL. The browser then makes a separate GET request on that URL. And that request has no knowledge of headers in the first one.

So sendRedirect won't work if you need to pass a header from Servlet A to Servlet B.

If you want this code to work - use RequestDispatcher in Servlet A (instead of sendRedirect). Also, it is always better to use relative path.

public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
    String userName=request.getParameter("userName");
    String newUrl = "ServletB";
    response.addHeader("REMOTE_USER", userName);
    RequestDispatcher view = request.getRequestDispatcher(newUrl);
    view.forward(request, response);
}

========================

public void doPost(HttpServletRequest request, HttpServletResponse response)
{
    String sss = response.getHeader("REMOTE_USER");
}

Using a Python subprocess call to invoke a Python script

subprocess.call expects the same arguments as subprocess.Popen - that is a list of strings (the argv in C) rather than a single string.

It's quite possible that your child process attempted to run "s" with the parameters "o", "m", "e", ...

How to pass parameters in $ajax POST?

I would recommend you to make use of the $.post or $.get syntax of jQuery for simple cases:

$.post('superman', { field1: "hello", field2 : "hello2"}, 
    function(returnedData){
         console.log(returnedData);
});

If you need to catch the fail cases, just do this:

$.post('superman', { field1: "hello", field2 : "hello2"}, 
    function(returnedData){
         console.log(returnedData);
}).fail(function(){
      console.log("error");
});

Additionally, if you always send a JSON string, you can use $.getJSON or $.post with one more parameter at the very end.

$.post('superman', { field1: "hello", field2 : "hello2"}, 
     function(returnedData){
        console.log(returnedData);
}, 'json');

Installing jdk8 on ubuntu- "unable to locate package" update doesn't fix

I used another repository for oracle java.

sudo add-apt-repository ppa:linuxuprising/java
sudo apt-get update

sudo apt install  oracle-java11-installer

How to get text and a variable in a messagebox

I wanto to display the count of rows in the excel sheet after the filter option has been applied.

So I declared the count of last rows as a variable that can be added to the Msgbox

Sub lastrowcall()
Dim hm As Worksheet
Dim dm As Worksheet
Set dm = ActiveWorkbook.Sheets("datecopy")
Set hm = ActiveWorkbook.Sheets("Home")
Dim lngStart As String, lngEnd As String
lngStart = hm.Range("E23").Value
lngEnd = hm.Range("E25").Value
Dim last_row As String
last_row = dm.Cells(Rows.Count, 1).End(xlUp).Row

MsgBox ("Number of test results between the selected dates " + lngStart + " 
and " + lngEnd + " are " + last_row + ". Please Select Yes to continue 
Analysis")


End Sub

How to connect to mysql with laravel?

It's also much more better to not modify the app/config/database.php file itself... otherwise modify .env file and put your DB info there. (.env file is available in Laravel 5, not sure if it was there in previous versions...)

NOTE: Of course you should have already set mysql as your default database connection in the app/config/database.php file.

split string only on first instance - java

As many other answers suggest the limit approach, This can be another way

You can use the indexOf method on String which will returns the first Occurance of the given character, Using that index you can get the desired output

String target = "apple=fruit table price=5" ;
int x= target.indexOf("=");
System.out.println(target.substring(x+1));

How do I parse a string to a float or int?

You need to take into account rounding to do this properly.

I.e. int(5.1) => 5 int(5.6) => 5 -- wrong, should be 6 so we do int(5.6 + 0.5) => 6

def convert(n):
    try:
        return int(n)
    except ValueError:
        return float(n + 0.5)

How to clear jQuery validation error messages?

I tested with:

$("div.error").remove();
$(".error").removeClass("error");

It will be ok, when you need to validate it again.

What do *args and **kwargs mean?

Notice the cool thing in S.Lott's comment - you can also call functions with *mylist and **mydict to unpack positional and keyword arguments:

def foo(a, b, c, d):
  print a, b, c, d

l = [0, 1]
d = {"d":3, "c":2}

foo(*l, **d)

Will print: 0 1 2 3

Escape a string in SQL Server so that it is safe to use in LIKE expression

Had a similar problem (using NHibernate, so the ESCAPE keyword would have been very difficult) and solved it using the bracket characters. So your sample would become

WHERE ... LIKE '%aa[%]bb%'

If you need proof:

create table test (field nvarchar(100))
go
insert test values ('abcdef%hijklm')
insert test values ('abcdefghijklm')
go
select * from test where field like 'abcdef[%]hijklm'
go

Is iterating ConcurrentHashMap values thread safe?

What does it mean?

It means that you should not try to use the same iterator in two threads. If you have two threads that need to iterate over the keys, values or entries, then they each should create and use their own iterators.

What happens if I try to iterate the map with two threads at the same time?

It is not entirely clear what would happen if you broke this rule. You could just get confusing behavior, in the same way that you do if (for example) two threads try to read from standard input without synchronizing. You could also get non-thread-safe behavior.

But if the two threads used different iterators, you should be fine.

What happens if I put or remove a value from the map while iterating it?

That's a separate issue, but the javadoc section that you quoted adequately answers it. Basically, the iterators are thread-safe, but it is not defined whether you will see the effects of any concurrent insertions, updates or deletions reflected in the sequence of objects returned by the iterator. In practice, it probably depends on where in the map the updates occur.

String to char array Java

A string to char array is as simple as

String str = "someString"; 
char[] charArray = str.toCharArray();

Can you explain a little more on what you are trying to do?

* Update *

if I am understanding your new comment, you can use a byte array and example is provided.

byte[] bytes = ByteBuffer.allocate(4).putInt(1695609641).array();

for (byte b : bytes) {
   System.out.format("0x%x ", b);
}

With the following output

0x65 0x10 0xf3 0x29

disable past dates on datepicker

you have just introduce parameter startDate as mentioned below.

var todaydate = new Date();
    $(".leave-day").datepicker({
        autoclose: true,
        todayBtn: "linked",
        todayHighlight: true,
        startDate: todaydate     
      }
    ).on('changeDate', function (e) {
        var dateCalendar = e.format();
        dateCalendar = moment(dateCalendar, 'MM/DD/YYYY').format('YYYY-MM-DD');
        $("#date-leave").val(dateCalendar);
    });

Could not load file or assembly 'Newtonsoft.Json, Version=4.5.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed'

This is very old, seems still many people having issues with the same thing. So I would like to share my experience that it might help someone.

I had the same issue in two places. In one project users 6.0.4.0 and in different project use 4.5.0.0.

1- This work for me. In bin folder I have 6.0.0.0 Newtonsoft.Json.dll and symbolic link to 4.5.0.0 dlls

<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<probing privatePath="bin\4.5dlls-path;" />
<assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" 
culture="neutral" />
<bindingRedirect oldVersion="0.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
</dependentAssembly>
</assemblyBinding>
</runtime>

If you don't know how to create symbolic link here.

mklink /D "name of the folder" "Path to the dll"

2- In this case when I remove the secion from Web config file it worked. Remember I have reference to 6.0.0.0 and 4.5.0.0 in different projects. In symbolic link I had 12.0.1.0 dll and bin 6.0.0.0.

<runtime>
<assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
<dependentAssembly>
<probing privatePath="bin\12.0.1dlls-path;" />
</dependentAssembly>
</assemblyBinding>
</runtime>

3- I have one more solution. If you have different versions of Newtonsoft.Json.dll in different projects try to upgrade all into one version or to the latest version, But in some case it might not work. Ex: System.Net.Http.Formatting.dll might need the version of Nettonsoft.Json.dll 6.0.0.0. In this case you need the vision 6.0.0.0, so try to make all into same version. Hope this might help some one.

Swift's guard keyword

There are really two big benefits to guard. One is avoiding the pyramid of doom, as others have mentioned – lots of annoying if let statements nested inside each other moving further and further to the right.

The other benefit is often the logic you want to implement is more "if not let” than "if let { } else".

Here’s an example: suppose you want to implement accumulate – a cross between map and reduce where it gives you back an array of running reduces. Here it is with guard:

extension Sliceable where SubSlice.Generator.Element == Generator.Element {

    func accumulate(combine: (Generator.Element,Generator.Element)->Generator.Element) -> [Generator.Element] {
        // if there are no elements, I just want to bail out and
        // return an empty array
        guard var running = self.first else { return [] }

        // running will now be an unwrapped non-optional
        var result = [running]

        // dropFirst is safe because the collection
        // must have at least one element at this point
        for x in dropFirst(self) {
            running = combine(running, x)
            result.append(running)
        }
        return result
    }

}


let a = [1,2,3].accumulate(+)  // [1,3,6]
let b = [Int]().accumulate(+)  // []

How would you write it without guard, but still using first that returns an optional? Something like this:

extension Sliceable where SubSlice.Generator.Element == Generator.Element {

    func accumulate(combine: (Generator.Element,Generator.Element)->Generator.Element) -> [Generator.Element] {

        if var running = self.first  {
            var result = [running]

            for x in dropFirst(self) {
                running = combine(running, x)
                result.append(running)
            }
            return result
        }
        else {
            return []
        }
    }

}

The extra nesting is annoying, but also, it’s not as logical to have the if and the else so far apart. It’s much more readable to have the early exit for the empty case, and then continue with the rest of the function as if that wasn’t a possibility.

SignalR Console app example

The Self-Host now uses Owin. Checkout http://www.asp.net/signalr/overview/signalr-20/getting-started-with-signalr-20/tutorial-signalr-20-self-host to setup the server. It's compatible with the client code above.

Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 32 bytes)

128M == 134217728, the number you are seeing.

The memory limit is working fine. When it says it tried to allocate 32 bytes, that the amount requested by the last operation before failing.

Are you building any huge arrays or reading large text files? If so, remember to free any memory you don't need anymore, or break the task down into smaller steps.

How to deal with INSTALL_PARSE_FAILED_INCONSISTENT_CERTIFICATES without uninstall?

I got this error even after uninstalling the original APK, which was mystifying. Finally I realized that I had set up multiple users on my Nexus 7 for testing and that the app was still installed for one of the other users. Once I uninstalled it for all users the error went away.

Submit form using <a> tag

Using Jquery you can do something like this:

_x000D_

$(document).ready(function() {_x000D_
  $('#btnSubmit').click(function() {_x000D_
    $('#deleteFrm').submit();_x000D_
  });_x000D_
_x000D_
});

_x000D_

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<form action="" id="deleteFrm" method="POST">_x000D_
  <a id="btnSubmit">Submit</a>_x000D_
</form>

_x000D_

How to send 100,000 emails weekly?

People have recommended MailChimp which is a good vendor for bulk email. If you're looking for a good vendor for transactional email, I might be able to help.

Over the past 6 months, we used four different SMTP vendors with the goal of figuring out which was the best one.

Here's a summary of what we found...

AuthSMTP

Cheapest around
No analysis/reporting
No tracking for opens/clicks
Had slight hesitation on some sends

Postmark

Very cheap, but not as cheap as AuthSMTP
Beautiful cpanel but no tracking on opens/clicks
Send-level activity tracking so you can open a single email that was sent and look at how it looked and the delivery data.
Have to use API. Sending by SMTP was recently introduced but it's buggy. For instance, we noticed that quotes (") in the subject line are stripped.
Cannot send any attachment you want. Must be on approved list of file types and under a certain size. (10 MB I think)
Requires a set list of from names/addresses.

JangoSMTP

Expensive in relation to the others – more than 10 times in some cases
Ugly cpanel but great tracking on opens/clicks with email-level detail
Had hesitation, at times, when sending. On two occasions, sends took an hour to be delivered
Requires a set list of from name/addresses.

SendGrid

Not quite a cheap as AuthSMTP but still very cheap. Many customers can exist on 200 free sends per day.
Decent cpanel but no in-depth detail on open/click tracking
Lots of API options. Options (open/click tracking, etc) can be custom defined on an email-by-email basis. Inbound (reply) email can be posted to our HTTP end point.
Absolutely zero hesitation on sends. Every email sent landed in the inbox almost immediately.
Can send from any from name/address.

Conclusion

SendGrid was the best with Postmark coming in second place. We never saw any hesitation in send times with either of those two - in some cases we sent several hundred emails at once - and they both have the best ROI, given a solid featureset.

VBA changing active workbook

Use ThisWorkbook which will refer to the original workbook which holds the code.

Alternatively at code start

Dim Wb As Workbook
Set Wb = ActiveWorkbook

sample code that activates all open books before returning to ThisWorkbook

Sub Test()
Dim Wb As Workbook
Dim Wb2 As Workbook
Set Wb = ThisWorkbook
For Each Wb2 In Application.Workbooks
    Wb2.Activate
Next
Wb.Activate
End Sub

Warning :-Presenting view controllers on detached view controllers is discouraged

Make sure you have a root view controller to start with. You can set it in didFinishLaunchingWithOptions.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    
    [window setRootViewController:viewController];
}

How to get the latest file in a folder?

I lack the reputation to comment but ctime from Marlon Abeykoons response did not give the correct result for me. Using mtime does the trick though. (key=os.path.getmtime))

import glob
import os

list_of_files = glob.glob('/path/to/folder/*') # * means all if need specific format then *.csv
latest_file = max(list_of_files, key=os.path.getmtime)
print latest_file

I found two answers for that problem:

python os.path.getctime max does not return latest Difference between python - getmtime() and getctime() in unix system

How many characters can a Java String have?

I believe they can be up to 2^31-1 characters, as they are held by an internal array, and arrays are indexed by integers in Java.

UL has margin on the left

I don't see any margin or margin-left declarations for #footer-wrap li.

This ought to do the trick:

#footer-wrap ul,
#footer-wrap li {
    margin-left: 0;
    list-style-type: none;
}

How does numpy.newaxis work and when to use it?

Simply put, numpy.newaxis is used to increase the dimension of the existing array by one more dimension, when used once. Thus,

1D array will become 2D array
2D array will become 3D array
3D array will become 4D array
4D array will become 5D array

and so on..

Here is a visual illustration which depicts promotion of 1D array to 2D arrays.

Scenario-1: np.newaxis might come in handy when you want to explicitly convert a 1D array to either a row vector or a column vector, as depicted in the above picture.

Example:

# 1D array
In [7]: arr = np.arange(4)
In [8]: arr.shape
Out[8]: (4,)

# make it as row vector by inserting an axis along first dimension
In [9]: row_vec = arr[np.newaxis, :]     # arr[None, :]
In [10]: row_vec.shape
Out[10]: (1, 4)

# make it as column vector by inserting an axis along second dimension
In [11]: col_vec = arr[:, np.newaxis]     # arr[:, None]
In [12]: col_vec.shape
Out[12]: (4, 1)

Scenario-2: When we want to make use of numpy broadcasting as part of some operation, for instance while doing addition of some arrays.

Example:

Let's say you want to add the following two arrays:

 x1 = np.array([1, 2, 3, 4, 5])
 x2 = np.array([5, 4, 3])

If you try to add these just like that, NumPy will raise the following ValueError :

ValueError: operands could not be broadcast together with shapes (5,) (3,)

In this situation, you can use np.newaxis to increase the dimension of one of the arrays so that NumPy can broadcast.

In [2]: x1_new = x1[:, np.newaxis]    # x1[:, None]
# now, the shape of x1_new is (5, 1)
# array([[1],
#        [2],
#        [3],
#        [4],
#        [5]])

Now, add:

In [3]: x1_new + x2
Out[3]:
array([[ 6,  5,  4],
       [ 7,  6,  5],
       [ 8,  7,  6],
       [ 9,  8,  7],
       [10,  9,  8]])

Alternatively, you can also add new axis to the array x2:

In [6]: x2_new = x2[:, np.newaxis]    # x2[:, None]
In [7]: x2_new     # shape is (3, 1)
Out[7]: 
array([[5],
       [4],
       [3]])

Now, add:

In [8]: x1 + x2_new
Out[8]: 
array([[ 6,  7,  8,  9, 10],
       [ 5,  6,  7,  8,  9],
       [ 4,  5,  6,  7,  8]])

Note: Observe that we get the same result in both cases (but one being the transpose of the other).

Scenario-3: This is similar to scenario-1. But, you can use np.newaxis more than once to promote the array to higher dimensions. Such an operation is sometimes needed for higher order arrays (i.e. Tensors).

Example:

In [124]: arr = np.arange(5*5).reshape(5,5)

In [125]: arr.shape
Out[125]: (5, 5)

# promoting 2D array to a 5D array
In [126]: arr_5D = arr[np.newaxis, ..., np.newaxis, np.newaxis]    # arr[None, ..., None, None]

In [127]: arr_5D.shape
Out[127]: (1, 5, 5, 1, 1)

As an alternative, you can use numpy.expand_dims that has an intuitive axis kwarg.

# adding new axes at 1st, 4th, and last dimension of the resulting array
In [131]: newaxes = (0, 3, -1)
In [132]: arr_5D = np.expand_dims(arr, axis=newaxes)
In [133]: arr_5D.shape
Out[133]: (1, 5, 5, 1, 1)

More background on np.newaxis vs np.reshape

newaxis is also called as a pseudo-index that allows the temporary addition of an axis into a multiarray.

np.newaxis uses the slicing operator to recreate the array while numpy.reshape reshapes the array to the desired layout (assuming that the dimensions match; And this is must for a reshape to happen).

Example

In [13]: A = np.ones((3,4,5,6))
In [14]: B = np.ones((4,6))
In [15]: (A + B[:, np.newaxis, :]).shape     # B[:, None, :]
Out[15]: (3, 4, 5, 6)

In the above example, we inserted a temporary axis between the first and second axes of B (to use broadcasting). A missing axis is filled-in here using np.newaxis to make the broadcasting operation work.

General Tip: You can also use None in place of np.newaxis; These are in fact the same objects.

In [13]: np.newaxis is None
Out[13]: True

P.S. Also see this great answer: newaxis vs reshape to add dimensions

How to prompt for user input and read command-line arguments

var = raw_input("Please enter something: ")
print "you entered", var

Or for Python 3:

var = input("Please enter something: ")
print("You entered: " + var)

Check if file exists and whether it contains a specific string

If you have the test binary installed or ksh has a matching built-in function, you could use it to perform your checks. Usually /bin/[ is a symbolic link to test:

if [ -e "$file_name" ]; then
  echo "File exists"
fi

if [ -z "$used_var" ]; then
  echo "Variable is empty"
fi

Remove a string from the beginning of a string

<?php
$str = 'bla_string_bla_bla_bla';
echo preg_replace('/bla_/', '', $str, 1); 
?>

Warning: require_once(): http:// wrapper is disabled in the server configuration by allow_url_include=0

You have to put the path to the file. For example:

require_once('../web/a.php');

You cannot get the file to require it from internet (with http protocol) it's restricted. The files must be on the same server. With Possibility to see each others (rights)

Dir-1 -
         > Folder-1 -> a.php
Dir-2 -
         > Folder-2 -> b.php

To include a.php inside b.php => require_once('../../Dir-1/Folder-1/a.php');
To include b.php inside a.php => require_once('../../Dir-2/Folder-2/b.php');

css background image in a different folder from css

you can use this

body{ background-image: url('../img/bg.png'); }

I tried this on my project where I need to set the background image of a div so I used this and it worked!

json_encode(): Invalid UTF-8 sequence in argument

Using this code might help. It solved my problem!

mb_convert_encoding($post["post"],'UTF-8','UTF-8');

or like that

mb_convert_encoding($string,'UTF-8','UTF-8');

Paste MS Excel data to SQL Server

If the interface works the way it did last I used it, you can select the region in Excel, copy it, open SQL Server and paste the data into the table as you would with Access.

Or you could setup an ODBC link between Excel and SQL Server.

Javascript to Select Multiple options

<script language="JavaScript" type="text/javascript">
<!--
function loopSelected()
{
  var txtSelectedValuesObj = document.getElementById('txtSelectedValues');
  var selectedArray = new Array();
  var selObj = document.getElementById('selSeaShells');
  var i;
  var count = 0;
  for (i=0; i<selObj.options.length; i++) {
    if (selObj.options[i].selected) {
      selectedArray[count] = selObj.options[i].value;
      count++;
    }
  }
  txtSelectedValuesObj.value = selectedArray;
}
function openInNewWindow(frm)
{
  // open a blank window
  var aWindow = window.open('', 'Tutorial004NewWindow',
   'scrollbars=yes,menubar=yes,resizable=yes,toolbar=no,width=400,height=400');

  // set the target to the blank window
  frm.target = 'Tutorial004NewWindow';

  // submit
  frm.submit();
}
//-->
</script>
The HTML
<form action="tutorial004_nw.html" method="get">
  <table border="1" cellpadding="10" cellspacing="0">
  <tr>
    <td valign="top">
      <input type="button" value="Submit" onclick="openInNewWindow(this.form);" />
      <input type="button" value="Loop Selected" onclick="loopSelected();" />
      <br />
      <select name="selSea" id="selSeaShells" size="5" multiple="multiple">
        <option value="val0" selected>sea zero</option>
        <option value="val1">sea one</option>
        <option value="val2">sea two</option>
        <option value="val3">sea three</option>
        <option value="val4">sea four</option>
      </select>
    </td>
    <td valign="top">
      <input type="text" id="txtSelectedValues" />
      selected array
    </td>
  </tr>
  </table>
</form>

Xcode 5 and iOS 7: Architecture and Valid architectures

None of the answers worked and then I was forgetting to set minimum deployment target which can be found in Project -> General -> Deployment Info -> Deployment Target -> 8.0

CardView not showing Shadow in Android L

Add android:hardwareAccelerated="true" in your manifests file like below it works for me

 <activity
        android:name=".activity.MyCardViewActivity"
        android:hardwareAccelerated="true"></activity>

TSQL How do you output PRINT in a user defined function?

You can try returning the variable you wish to inspect. E.g. I have this function:

--Contencates seperate date and time strings and converts to a datetime. Date should be in format 25.03.2012. Time as 9:18:25.
ALTER FUNCTION [dbo].[ufn_GetDateTime] (@date nvarchar(11), @time nvarchar(11))
RETURNS datetime
AS
BEGIN

        --select dbo.ufn_GetDateTime('25.03.2012.', '9:18:25')

    declare @datetime datetime

    declare @day_part nvarchar(3)
    declare @month_part nvarchar(3)
    declare @year_part nvarchar(5)

    declare @point_ix int

    set @point_ix = charindex('.', @date)
    set @day_part = substring(@date, 0, @point_ix)

    set @date = substring(@date, @point_ix, len(@date) - @point_ix)
    set @point_ix = charindex('.', @date)

    set @month_part = substring(@date, 0, @point_ix)

    set @date = substring(@date, @point_ix, len(@date) - @point_ix)
    set @point_ix = charindex('.', @date)

    set @year_part = substring(@date, 0, @point_ix)

    set @datetime = @month_part + @day_part  + @year_part + ' ' + @time

    return @datetime
END

When I run it.. I get: Msg 241, Level 16, State 1, Line 1 Conversion failed when converting date and/or time from character string.

Arghh!!

So, what do I do?

ALTER FUNCTION [dbo].[ufn_GetDateTime] (@date nvarchar(11), @time nvarchar(11))
RETURNS nvarchar(22)
AS
BEGIN

        --select dbo.ufn_GetDateTime('25.03.2012.', '9:18:25')

    declare @day_part nvarchar(3)
    declare @point_ix int

    set @point_ix = charindex('.', @date)
    set @day_part = substring(@date, 0, @point_ix)

    return @day_part
END

And I get '25'. So, I am off by one and so I change to..

set @day_part = substring(@date, 0, @point_ix + 1)

Voila! Now it works :)

Populating a dictionary using for loops (python)

>>> dict(zip(keys, values))
{0: 'Hi', 1: 'I', 2: 'am', 3: 'John'}

How to convert int to float in python?

You can just multiply 1.0

>>> 1.0*144/314
0.4585987261146497

Switch/toggle div (jQuery)

I used this way to do that for multiple blocks without conjuring new JavaScript code:

<a href="#" data-toggle="thatblock">Show/Hide Content</a>

<div id="thatblock" style="display: none">
  Here is some description that will appear when we click on the button
</div>

Then a JavaScript portion for all such cases:

$(function() {
  $('*[data-toggle]').click(function() {
    $('#'+$(this).attr('data-toggle')).toggle();
    return false;
  });
});

Using gdb to single-step assembly code outside specified executable causes error "cannot find bounds of current function"

You can use stepi or nexti (which can be abbreviated to si or ni) to step through your machine code.

How do I set up NSZombieEnabled in Xcode 4?

Jano's answer is the easiest way to find it.. another way would be if you click on the scheme drop down bar -> edit scheme -> arguments tab and then add NSZombieEnabled in the Environment Variables column and YES in the value column...

Change the mouse cursor on mouse over to anchor-like style

If you want to do this in jQuery instead of CSS, you basically follow the same process.

Assuming you have some <div id="target"></div>, you can use the following code:

$("#target").hover(function() {
    $(this).css('cursor','pointer');
}, function() {
    $(this).css('cursor','auto');
});

and that should do it.

Extract subset of key-value pairs from Python dictionary object?

This answer uses a dictionary comprehension similar to the selected answer, but will not except on a missing item.

python 2 version:

{k:v for k, v in bigDict.iteritems() if k in ('l', 'm', 'n')}

python 3 version:

{k:v for k, v in bigDict.items() if k in ('l', 'm', 'n')}

How do I use sudo to redirect output to a location I don't have permission to write to?

Yet another variation on the theme:

sudo bash <<EOF
ls -hal /root/ > /root/test.out
EOF

Or of course:

echo 'ls -hal /root/ > /root/test.out' | sudo bash

They have the (tiny) advantage that you don't need to remember any arguments to sudo or sh/bash

Auto height of div

According to this, you need to assign a height to the element in which the div is contained in order for 100% height to work. Does that work for you?

How to encode URL parameters?

With urlsearchparams:

const params = new URLSearchParams()
params.append('imageurl', http://www.image.com/?username=unknown&password=unknown)
return `http://www.foobar.com/foo?${params.toString()}`

Unable to locate tools.jar

Yes, you've downloaded and installed the Java Runtime Environment (JRE) instead of the Java Development Kit (JDK). The latter has the tools.jar, java.exe, javac.exe, etc.

import dat file into R

The dat file has some lines of extra information before the actual data. Skip them with the skip argument:

read.table("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat", 
           header=TRUE, skip=3)

An easy way to check this if you are unfamiliar with the dataset is to first use readLines to check a few lines, as below:

readLines("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat", 
          n=10)
# [1] "Ozone data from CZ03 2009"   "Local time: GMT + 0"        
# [3] ""                            "Date        Hour      Value"
# [5] "01.01.2009 00:00       34.3" "01.01.2009 01:00       31.9"
# [7] "01.01.2009 02:00       29.9" "01.01.2009 03:00       28.5"
# [9] "01.01.2009 04:00       32.9" "01.01.2009 05:00       20.5"

Here, we can see that the actual data starts at [4], so we know to skip the first three lines.

Update

If you really only wanted the Value column, you could do that by:

as.vector(
    read.table("http://www.nilu.no/projects/ccc/onlinedata/ozone/CZ03_2009.dat",
               header=TRUE, skip=3)$Value)

Again, readLines is useful for helping us figure out the actual name of the columns we will be importing.

But I don't see much advantage to doing that over reading the whole dataset in and extracting later.

Match multiline text using regular expression

str.matches(regex) behaves like Pattern.matches(regex, str) which attempts to match the entire input sequence against the pattern and returns

true if, and only if, the entire input sequence matches this matcher's pattern

Whereas matcher.find() attempts to find the next subsequence of the input sequence that matches the pattern and returns

true if, and only if, a subsequence of the input sequence matches this matcher's pattern

Thus the problem is with the regex. Try the following.

String test = "User Comments: This is \t a\ta \ntest\n\n message \n";

String pattern1 = "User Comments: [\\s\\S]*^test$[\\s\\S]*";
Pattern p = Pattern.compile(pattern1, Pattern.MULTILINE);
System.out.println(p.matcher(test).find());  //true

String pattern2 = "(?m)User Comments: [\\s\\S]*^test$[\\s\\S]*";
System.out.println(test.matches(pattern2));  //true

Thus in short, the (\\W)*(\\S)* portion in your first regex matches an empty string as * means zero or more occurrences and the real matched string is User Comments: and not the whole string as you'd expect. The second one fails as it tries to match the whole string but it can't as \\W matches a non word character, ie [^a-zA-Z0-9_] and the first character is T, a word character.

What is the cause for "angular is not defined"

I had the same problem as deke. I forgot to include the most important script: angular.js :)

<script type="text/javascript" src="bower_components/angular/angular.min.js"></script>

Head and tail in one line

Python 2, using lambda

>>> head, tail = (lambda lst: (lst[0], lst[1:]))([1, 1, 2, 3, 5, 8, 13, 21, 34, 55])
>>> head
1
>>> tail
[1, 2, 3, 5, 8, 13, 21, 34, 55]

What are all the differences between src and data-src attributes?

The attributes src and data-src have nothing in common, except that they are both allowed by HTML5 CR and they both contain the letters src. Everything else is different.

The src attribute is defined in HTML specs, and it has a functional meaning.

The data-src attribute is just one of the infinite set of data-* attributes, which have no defined meaning but can be used to include invisible data in an element, for use in scripting (or styling).

Send a file through sockets in Python

How to use PowerShell select-string to find more than one pattern in a file?

If you want to match the two words in either order, use:

gci C:\Logs| select-string -pattern '(VendorEnquiry.*Failed)|(Failed.*VendorEnquiry)'

If Failed always comes after VendorEnquiry on the line, just use:

gci C:\Logs| select-string -pattern '(VendorEnquiry.*Failed)'

List all files from a directory recursively with Java

public class GetFilesRecursive {
    public static List <String> getFilesRecursively(File dir){
        List <String> ls = new ArrayList<String>();
        for (File fObj : dir.listFiles()) {
            if(fObj.isDirectory()) {
                ls.add(String.valueOf(fObj));
                ls.addAll(getFilesRecursively(fObj));               
            } else {
                ls.add(String.valueOf(fObj));       
            }
        }

        return ls;
    }
    public static List <String> getListOfFiles(String fullPathDir) {
        List <String> ls = new ArrayList<String> ();
        File f = new File(fullPathDir);
        if (f.exists()) {
            if(f.isDirectory()) {
                ls.add(String.valueOf(f));
                ls.addAll(getFilesRecursively(f));
            }
        } else {
            ls.add(fullPathDir);
        }
        return ls;
    }

    public static void main(String[] args) {
        List <String> ls = getListOfFiles("/Users/srinivasab/Documents");
        for (String file:ls) {
            System.out.println(file);
        }
        System.out.println(ls.size());
    }
}

Duplicate / Copy records in the same MySQL table

Your approach is good but the problem is that you use "*" instead enlisting fields names. If you put all the columns names excep primary key your script will work like charm on one or many records.

INSERT INTO invoices (iv.field_name, iv.field_name,iv.field_name
) SELECT iv.field_name, iv.field_name,iv.field_name FROM invoices AS iv     
WHERE iv.ID=XXXXX

server certificate verification failed. CAfile: /etc/ssl/certs/ca-certificates.crt CRLfile: none

What worked for me when trying to git clone inside of a Dockerfile was to fetch the SSL certificate and add it to the local certificate list:

openssl s_client -showcerts -servername git.mycompany.com -connect git.mycompany.com:443 </dev/null 2>/dev/null | sed -n -e '/BEGIN\ CERTIFICATE/,/END\ CERTIFICATE/ p'  > git-mycompany-com.pem

cat git-mycompany-com.pem | sudo tee -a /etc/ssl/certs/ca-certificates.crt

Credits: https://fabianlee.org/2019/01/28/git-client-error-server-certificate-verification-failed/

GIT_DISCOVERY_ACROSS_FILESYSTEM not set

Just type git init into your command line and press enter. Then run your command again, you probably were running git remote add origin [your-repository].

That should work, if it doesn't, just let me know.

Where is the Query Analyzer in SQL Server Management Studio 2008 R2?

I don't know if this helps but I just installed Server 2008 Express and was disappointed when I couldn't find the query analyzer but I was able to use the command line 'sqlcmd' to access my server. It is a pain to use but it works. You can write your code in a text file then import it using the sqlcmd command. You also have to end your query with a new line and type the word 'go'.

Example of query file named test.sql:
use master;
select name, crdate from sysdatabases where xtype='u' order by crdate desc;
go

Example of sqlcmd:
sqlcmd -S %computername%\RLH -d play -i "test.sql" -o outfile.sql & notepad outfile.sql

python: sys is not defined

In addition to the answers given above, check the last line of the error message in your console. In my case, the 'site-packages' path in sys.path.append('.....') was wrong.

MongoDB or CouchDB - fit for production?

Here's a list of production deployed sites with mongoDB

The New Yorks Times: Using it in a form-building application for photo submissions. Mongo's lack of schema gives producers the ability to define any combination of custom form fields.
SourceForge: is used for back-end storage on the SourceForge front pages, project pages, and download pages for all projects.
Bit.ly
Etsy
IGN: powers IGN’s real-time traffic analytics and RESTful Content APIs.
Justin.tv: powers Justin.tv's internal analytics tools for virality, user retention, and general usage stats that out-of-the-box solutions can't provide.
Posterous
Intuit
Foursquare: Sharded Mongo databases are used for most data at foursquare.
Business Insider: Using it since the beginning of 2008. All of the site's data, including posts, comments, and even the images, are stored on MongoDB.
Github: is used for an internal reporting application.
Examiner: migrated their site from Cold Fusion and SQL Server to Drupal 7 and MongoDB.
Grooveshark: currently uses Mongo to manage over one million unique user sessions per day.
Buzzfeed
Discus
Evite: Used for analytics and quick reporting.
Squarespace
Shutterfly: is used for various persistent data storage requirements within Shutterfly. MongoDB helps Shutterfly build an unrivaled service that enables deeper, more personal relationships between customers and those who matter most in their lives.
Topsy
Sharethis
Mongohq: provides a hosting platform for MongoDB and also uses MongoDB as the back-end for its service. Our hosting centers page provides more information about MongoHQ and other MongoDB hosting options.

and more...

Extracted from: http://lineofthought.com/tools/mongodb

You can check other databases or tools there too.

Java enum - why use toString instead of name

While most people blindly follow the advice of the javadoc, there are very specific situations where you want to actually avoid toString(). For example, I'm using enums in my Java code, but they need to be serialized to a database, and back again. If I used toString() then I would technically be subject to getting the overridden behavior as others have pointed out.

Additionally one can also de-serialize from the database, for example, this should always work in Java:

MyEnum taco = MyEnum.valueOf(MyEnum.TACO.name());

Whereas this is not guaranteed:

MyEnum taco = MyEnum.valueOf(MyEnum.TACO.toString());

By the way, I find it very odd for the Javadoc to explicitly say "most programmers should". I find very little use-case in the toString of an enum, if people are using that for a "friendly name" that's clearly a poor use-case as they should be using something more compatible with i18n, which would, in most cases, use the name() method.

How to read and write excel file

This will write a JTable to a tab separated file that can be easily imported into Excel. This works.

If you save an Excel worksheet as an XML document you could also build the XML file for EXCEL with code. I have done this with word so you do not have to use third-party packages.

This could code have the JTable taken out and then just write a tab separated to any text file and then import into Excel. I hope this helps.

Code:

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import javax.swing.JTable;
import javax.swing.table.TableModel;

public class excel {
    String columnNames[] = { "Column 1", "Column 2", "Column 3" };

    // Create some data
    String dataValues[][] =
    {
        { "12", "234", "67" },
        { "-123", "43", "853" },
        { "93", "89.2", "109" },
        { "279", "9033", "3092" }
    };

    JTable table;

    excel() {
        table = new JTable( dataValues, columnNames );
    }


    public void toExcel(JTable table, File file){
        try{
            TableModel model = table.getModel();
            FileWriter excel = new FileWriter(file);

            for(int i = 0; i < model.getColumnCount(); i++){
                excel.write(model.getColumnName(i) + "\t");
            }

            excel.write("\n");

            for(int i=0; i< model.getRowCount(); i++) {
                for(int j=0; j < model.getColumnCount(); j++) {
                    excel.write(model.getValueAt(i,j).toString()+"\t");
                }
                excel.write("\n");
            }

            excel.close();

        }catch(IOException e){ System.out.println(e); }
    }

    public static void main(String[] o) {
        excel cv = new excel();
        cv.toExcel(cv.table,new File("C:\\Users\\itpr13266\\Desktop\\cs.tbv"));
    }
}

Debugging the error "gcc: error: x86_64-linux-gnu-gcc: No such file or directory"

I was getting the error “gcc: error: x86_64-linux-gnu-gcc: No such file or directory” as I was trying to build a simple c-extension module to run in Python. I tried all the things above to no avail, and finally realized that I had an error in my module.c code! So I thought it would be helpful to add that, if you are getting this error message but you have python-dev and everything correctly installed, you should look for issues in your code.

How to specify preference of library path?

Specifying the absolute path to the library should work fine:

g++ /my/dir/libfoo.so.0  ...

Did you remember to remove the -lfoo once you added the absolute path?

When do I use super()?

From oracle documentation page:

If your method overrides one of its superclass's methods, you can invoke the overridden method through the use of the keyword super.

You can also use super to refer to a hidden field (although hiding fields is discouraged).

Use of super in constructor of subclasses:

Invocation of a superclass constructor must be the first line in the subclass constructor.

The syntax for calling a superclass constructor is

super();

or:

super(parameter list);

With super(), the superclass no-argument constructor is called. With super(parameter list), the superclass constructor with a matching parameter list is called.

Note: If a constructor does not explicitly invoke a superclass constructor, the Java compiler automatically inserts a call to the no-argument constructor of the superclass. If the super class does not have a no-argument constructor, you will get a compile-time error.

Polymorphism vs Overriding vs Overloading

What is a method group in C#?

Also, if you are using LINQ, you can apparently do something like myList.Select(methodGroup).

So, for example, I have:

private string DoSomethingToMyString(string input)
{
    // blah
}

Instead of explicitly stating the variable to be used like this:

public List<string> GetStringStuff()
{
    return something.getStringsFromSomewhere.Select(str => DoSomethingToMyString(str));
}

I can just omit the name of the var:

public List<string> GetStringStuff()
{
    return something.getStringsFromSomewhere.Select(DoSomethingToMyString);
}

SQL - How to find the highest number in a column?

In PHP:

$sql = mysql_query("select id from customers order by id desc");
$rs = mysql_fetch_array($sql);
if ( !$rs ) { $newid = 1; } else { $newid = $rs[newid]+1; }

thus $newid = 23 if last record in column id was 22.

Delete files older than 15 days using PowerShell

Try this:

dir C:\PURGE -recurse | 
where { ((get-date)-$_.creationTime).days -gt 15 } | 
remove-item -force

MySQL: Grant all privileges on database

This is old question but I don't think the accepted answer is safe. It's good for creating a super user but not good if you want to grant privileges on a single database.

grant all privileges on mydb.* to myuser@'%' identified by 'mypasswd';
grant all privileges on mydb.* to myuser@localhost identified by 'mypasswd';

% seems to not cover socket communications, that the localhost is for. WITH GRANT OPTION is only good for the super user, otherwise it is usually a security risk.

Update for MySQL 5.7+ seems like this warns about:

Using GRANT statement to modify existing user's properties other than privileges is deprecated and will be removed in future release. Use ALTER USER statement for this operation.

So setting password should be with separate commands. Thanks to comment from @scary-wombat.

ALTER USER 'myuser'@'%' IDENTIFIED BY 'mypassword';
ALTER USER 'myuser'@'localhost' IDENTIFIED BY 'mypassword';

Hope this helps.

Making an image act like a button

You could implement a JavaScript block which contains a function with your needs.

<div style="position: absolute; left: 10px; top: 40px;"> 
    <img src="logg.png" width="114" height="38" onclick="DoSomething();" />
</div>

Recommended way to insert elements into map

Use insert if you want to insert a new element. insert will not overwrite an existing element, and you can verify that there was no previously exising element:

if ( !myMap.insert( std::make_pair( key, value ) ).second ) {
    //  Element already present...
}

Use [] if you want to overwrite a possibly existing element:

myMap[ key ] = value;
assert( myMap.find( key )->second == value ); // post-condition

This form will overwrite any existing entry.

Set "Homepage" in Asp.Net MVC

Step 1: Click on Global.asax File in your Solution.

Step 2: Then Go to Definition of

RouteConfig.RegisterRoutes(RouteTable.Routes);

Step 3: Change Controller Name and View Name

public class RouteConfig
{
    public static void RegisterRoutes(RouteCollection routes)
    {
        routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

        routes.MapRoute(name: "Default",
                        url: "{controller}/{action}/{id}",
                        defaults: new { controller = "Home", 
                                        action = "Index", 
                                        id = UrlParameter.Optional }
                        );
    }
}

How to Bootstrap navbar static to fixed on scroll?

If you handle the code like this:

<div class="scroll"> 
<div class="menu">home | services | contact</div>
</div>

And css:

.scroll {
  margin-bottom:50px;
}
.menu {
  position:absolute;
  background:#428bca;
  color:#fff;
  line-height:30px;
  letter-spacing:1px;
  width:100%;
  height:50px;
}
.menu-padding {
  // no  style here anymore 
}

Then the annoying scroll is gone.

The compleet code and fiddle is not originally made by me, I got it from an earlier answer in this topic. The change in the code is made by me

Fabian #Web-Stars

jsfiddle

Change the Bootstrap Modal effect

If you take a look at the bootstraps fade class used with the modal window you will find, that all it does, is to set the opacity value to 0 and adds a transition for the opacity rule.

Whenever you launch a modal the in class is added and will change the opacity to a value of 1.

Knowing that you can easily build your own fade-scale class.

Here is an example.

_x000D_

@import url("https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css");_x000D_
_x000D_
.fade-scale {_x000D_
  transform: scale(0);_x000D_
  opacity: 0;_x000D_
  -webkit-transition: all .25s linear;_x000D_
  -o-transition: all .25s linear;_x000D_
  transition: all .25s linear;_x000D_
}_x000D_
_x000D_
.fade-scale.in {_x000D_
  opacity: 1;_x000D_
  transform: scale(1);_x000D_
}

_x000D_

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.0/jquery.min.js"></script>_x000D_
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>_x000D_
_x000D_
<!-- Button trigger modal -->_x000D_
<button type="button" class="btn btn-primary btn-lg" data-toggle="modal" data-target="#myModal">_x000D_
  Launch demo modal_x000D_
</button>_x000D_
_x000D_
<!-- Modal -->_x000D_
<div class="modal fade-scale" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">_x000D_
  <div class="modal-dialog" role="document">_x000D_
    <div class="modal-content">_x000D_
      <div class="modal-header">_x000D_
        <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>_x000D_
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>_x000D_
      </div>_x000D_
      <div class="modal-body">_x000D_
        ..._x000D_
      </div>_x000D_
      <div class="modal-footer">_x000D_
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>_x000D_
        <button type="button" class="btn btn-primary">Save changes</button>_x000D_
      </div>_x000D_
    </div>_x000D_
  </div>_x000D_
</div>

_x000D_

-- UPDATE --

This answer is getting more up votes lately so i figured i add an update to show how easy it is to customize the BS modal in and out animations with the help of the great Animate.css library by
Daniel Eden.

All that needs to be done is to include the stylesheet to your <head></head> section. Now you simply need to add the animated class, plus one of the entrance classes of the library to the modal element.

<div class="modal animated fadeIn" id="myModal" tabindex="-1" role="dialog" ...>
  ...
</div>

But there is also a way to add an out animation to the modal window and since the library has a bunch of cool animations that will make an element disappear, why not use them. :)

To use them you will need to toggle the classes on the modal element, so it is actually better to call the modal window via JavaScript, which is described here.

You will also need to listen for some of the modal events to know when it's time to add or remove the classes from the modal element. The events being fired are described here.

To trigger a custom out animation you can't use the data-dismiss="modal" attribute on a button inside the modal window that's suppose to close the modal. You can simply add your own attribute like data-custom-dismiss="modal" and use that to call the $('selector').modal.('hide') method on it.

Here is an example that shows all the different possibilities.

_x000D_

/* -------------------------------------------------------_x000D_
| This first part can be ignored, it is just getting_x000D_
| all the different entrance and exit classes of the_x000D_
| animate-config.json file from the github repo._x000D_
--------------------------------------------------------- */_x000D_
_x000D_
var animCssConfURL = 'https://api.github.com/repos/daneden/animate.css/contents/animate-config.json';_x000D_
var selectIn = $('#animation-in-types');_x000D_
var selectOut = $('#animation-out-types');_x000D_
var getAnimCSSConfig = function ( url ) { return $.ajax( { url: url, type: 'get', dataType: 'json' } ) };_x000D_
var decode = function ( data ) {_x000D_
  var bin = Uint8Array.from( atob( data['content'] ), function( char ) { return char.charCodeAt( 0 ) } );_x000D_
  var bin2Str = String.fromCharCode.apply( null, bin );_x000D_
  return JSON.parse( bin2Str )_x000D_
}_x000D_
var buildSelect = function ( which, name, animGrp ) {_x000D_
  var grp = $('<optgroup></optgroup>');_x000D_
  grp.attr('label', name);_x000D_
  $.each(animGrp, function ( idx, animType ) {_x000D_
    var opt = $('<option></option>')_x000D_
    opt.attr('value', idx)_x000D_
    opt.text(idx)_x000D_
    grp.append(opt);_x000D_
  })_x000D_
  which.append(grp) _x000D_
}_x000D_
getAnimCSSConfig( animCssConfURL )_x000D_
  .done (function ( data ) {_x000D_
  var animCssConf = decode ( data );_x000D_
  $.each(animCssConf, function(name, animGrp) {_x000D_
    if ( /_entrances/.test(name) ) {_x000D_
      buildSelect(selectIn, name, animGrp);_x000D_
    }_x000D_
    if ( /_exits/.test(name) ) {_x000D_
      buildSelect(selectOut, name, animGrp);_x000D_
    }_x000D_
  })_x000D_
})_x000D_
_x000D_
_x000D_
/* -------------------------------------------------------_x000D_
| Here is were the fun begins._x000D_
--------------------------------------------------------- */_x000D_
_x000D_
var modalBtn = $('button');_x000D_
var modal = $('#myModal');_x000D_
var animInClass = "";_x000D_
var animOutClass = "";_x000D_
_x000D_
modalBtn.on('click', function() {_x000D_
  animInClass = selectIn.find('option:selected').val();_x000D_
  animOutClass = selectOut.find('option:selected').val();_x000D_
  if ( animInClass == '' || animOutClass == '' ) {_x000D_
    alert("Please select an in and out animation type.");_x000D_
  } else {_x000D_
    modal.addClass(animInClass);_x000D_
    modal.modal({backdrop: false});_x000D_
  }_x000D_
})_x000D_
_x000D_
modal.on('show.bs.modal', function () {_x000D_
  var closeModalBtns = modal.find('button[data-custom-dismiss="modal"]');_x000D_
  closeModalBtns.one('click', function() {_x000D_
    modal.on('webkitAnimationEnd oanimationend msAnimationEnd animationend', function( evt ) {_x000D_
      modal.modal('hide')_x000D_
    });_x000D_
    modal.removeClass(animInClass).addClass(animOutClass);_x000D_
  })_x000D_
})_x000D_
_x000D_
modal.on('hidden.bs.modal', function ( evt ) {_x000D_
  var closeModalBtns = modal.find('button[data-custom-dismiss="modal"]');_x000D_
  modal.removeClass(animOutClass)_x000D_
  modal.off('webkitAnimationEnd oanimationend msAnimationEnd animationend')_x000D_
  closeModalBtns.off('click')_x000D_
})

_x000D_

@import url('https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css');_x000D_
@import url('https://cdnjs.cloudflare.com/ajax/libs/animate.css/3.5.2/animate.css');_x000D_
_x000D_
select, button:not([data-custom-dismiss="modal"]) {_x000D_
  margin: 10px 0;_x000D_
  width: 220px;_x000D_
}

_x000D_

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>_x000D_
_x000D_
<div class="container">_x000D_
  <div class="row">_x000D_
    <div class="col-xs-4 col-xs-offset-4 col-sm-4 col-sm-offset-4">_x000D_
      <select id="animation-in-types">_x000D_
        <option value="" selected>Choose animation-in type</option>_x000D_
      </select>_x000D_
    </div>_x000D_
  </div>_x000D_
  <div class="row">_x000D_
    <div class="col-xs-4 col-xs-offset-4 col-sm-4 col-sm-offset-4">_x000D_
      <select id="animation-out-types">_x000D_
        <option value="" selected>Choose animation-out type</option>_x000D_
      </select>_x000D_
    </div>_x000D_
  </div>_x000D_
  <div class="row">_x000D_
    <div class="col-xs-4 col-xs-offset-4 col-sm-4 col-sm-offset-4">_x000D_
      <button class="btn btn-default">Open Modal</button>_x000D_
    </div>_x000D_
  </div>_x000D_
</div>_x000D_
_x000D_
<!-- Modal -->_x000D_
<div class="modal animated" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel">_x000D_
  <div class="modal-dialog" role="document">_x000D_
    <div class="modal-content">_x000D_
      <div class="modal-header">_x000D_
        <button type="button" class="close" data-custom-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button>_x000D_
        <h4 class="modal-title" id="myModalLabel">Modal title</h4>_x000D_
      </div>_x000D_
      <div class="modal-body">_x000D_
        ..._x000D_
      </div>_x000D_
      <div class="modal-footer">_x000D_
        <button type="button" class="btn btn-default" data-custom-dismiss="modal">Close</button>_x000D_
      </div>_x000D_
    </div>_x000D_
  </div>_x000D_
</div>

_x000D_

How to search a Git repository by commit message?

To search the commit log (across all branches) for the given text:

git log --all --grep='Build 0051'

To search the actual content of commits through a repo's history, use:

git grep 'Build 0051' $(git rev-list --all)

to show all instances of the given text, the containing file name, and the commit sha1.

Finally, as a last resort in case your commit is dangling and not connected to history at all, you can search the reflog itself with the -g flag (short for --walk-reflogs:

git log -g --grep='Build 0051'

EDIT: if you seem to have lost your history, check the reflog as your safety net. Look for Build 0051 in one of the commits listed by

git reflog

You may have simply set your HEAD to a part of history in which the 'Build 0051' commit is not visible, or you may have actually blown it away. The git-ready reflog article may be of help.

To recover your commit from the reflog: do a git checkout of the commit you found (and optionally make a new branch or tag of it for reference)

git checkout 77b1f718d19e5cf46e2fab8405a9a0859c9c2889
# alternative, using reflog (see git-ready link provided)
# git checkout HEAD@{10}
git checkout -b build_0051 # make a new branch with the build_0051 as the tip

Delete a closed pull request from GitHub

5 step to do what you want if you made the pull request from a forked repository:

reopen the pull request
checkout to the branch which you made the pull request
reset commit to the last master commit(that means remove all you new code)
git push --force
delete your forked repository which made the pull request

And everything is done, good luck!

java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver

I had the same problem but was able to fix it by doing the following:

Right-click on the project -> Properties, then add the JAR (odjbc6 or 14) file in the deployment assembly.

Select data from "show tables" MySQL query

I think what you want is MySQL's information_schema view(s): http://dev.mysql.com/doc/refman/5.0/en/tables-table.html

Hook up Raspberry Pi via Ethernet to laptop without router?

configure static ip on the raspberry pi:

sudo nano /etc/network/interfaces

and then add:

iface eth0 inet static
     address 169.254.0.2
     netmask 255.255.255.0
     broadcast 169.254.0.255

then you can acces your raspberry via ssh

ssh [email protected]

How to connect to LocalDb

Suppose: SqlConnection connectionObj = new SqlConnection()

for : connectionObj.ConnectionString -> use server name : (localdb)\\MSSQLLocalDB.

Note: Double back slash

for : App.config -> use server name : (localdb)\MSSQLLocalDB

Note: Single back slash

How to convert a single char into an int

Any problems with the following way of doing it?

int CharToInt(const char c)
{
    switch (c)
    {
    case '0':
        return 0;
    case '1':
        return 1;
    case '2':
        return 2;
    case '3':
        return 3;
    case '4':
        return 4;
    case '5':
        return 5;
    case '6':
        return 6;
    case '7':
        return 7;
    case '8':
        return 8;
    case '9':
        return 9;
    default:
        return 0;
    }
}

What does "SyntaxError: Missing parentheses in call to 'print'" mean in Python?

If your code should work in both Python 2 and 3, you can achieve this by loading this at the beginning of your program:

from __future__ import print_function   # If code has to work in Python 2 and 3!

Then you can print in the Python 3 way:

print("python")

If you want to print something without creating a new line - you can do this:

for number in range(0, 10):
    print(number, end=', ')

Android Relative Layout Align Center

If you want to make it center then use android:layout_centerVertical="true" in the TextView.

What is the use of a cursor in SQL Server?

In SQL server, a cursor is used when you need Instead of the T-SQL commands that operate on all the rows in the result set one at a time, we use a cursor when we need to update records in a database table in a singleton fashion, in other words row by row.to fetch one row at a time or row by row.

Working with cursors consists of several steps:

Declare - Declare is used to define a new cursor. Open - A Cursor is opened and populated by executing the SQL statement defined by the cursor. Fetch - When the cursor is opened, rows can be retrieved from the cursor one by one. Close - After data operations, we should close the cursor explicitly. Deallocate - Finally, we need to delete the cursor definition and release all the system resources associated with the cursor. Syntax

Multipart forms from C# client

With .NET 4.5 you currently could use System.Net.Http namespace. Below the example for uploading single file using multipart form data.

using System;
using System.IO;
using System.Net.Http;

namespace HttpClientTest
{
    class Program
    {
        static void Main(string[] args)
        {
            var client = new HttpClient();
            var content = new MultipartFormDataContent();
            content.Add(new StreamContent(File.Open("../../Image1.png", FileMode.Open)), "Image", "Image.png");
            content.Add(new StringContent("Place string content here"), "Content-Id in the HTTP"); 
            var result = client.PostAsync("https://hostname/api/Account/UploadAvatar", content);
            Console.WriteLine(result.Result.ToString());
        }
    }
}

Rails migration for change column

I'm not aware if you can create a migration from the command line to do all this, but you can create a new migration, then edit the migration to perform this taks.

If tablename is the name of your table, fieldname is the name of your field and you want to change from a datetime to date, you can write a migration to do this.

You can create a new migration with:

rails g migration change_data_type_for_fieldname

Then edit the migration to use change_table:

class ChangeDataTypeForFieldname < ActiveRecord::Migration
  def self.up
    change_table :tablename do |t|
      t.change :fieldname, :date
    end
  end
  def self.down
    change_table :tablename do |t|
      t.change :fieldname, :datetime
    end
  end
end

Then run the migration:

rake db:migrate

how to create dynamic two dimensional array in java?

List<Integer>[] array;  
array = new List<Integer>[10];

this the second case in @TofuBeer's answer is incorrect. because can't create arrays with generics. u can use:

List<List<Integer>> array = new ArrayList<>();

how to set ASPNETCORE_ENVIRONMENT to be considered for publishing an asp.net core application?

Option1:

To set the ASPNETCORE_ENVIRONMENT environment variable in windows,

Command line - setx ASPNETCORE_ENVIRONMENT "Development"

PowerShell - $Env:ASPNETCORE_ENVIRONMENT = "Development"

For other OS refer this - https://docs.microsoft.com/en-us/aspnet/core/fundamentals/environments

Option2:

If you want to set ASPNETCORE_ENVIRONMENT using web.config then add aspNetCore like this-

<configuration>
  <!--
    Configure your application settings in appsettings.json. Learn more at http://go.microsoft.com/fwlink/?LinkId=786380
  -->
  <system.webServer>
    <handlers>
      <add name="aspNetCore" path="*" verb="*" modules="AspNetCoreModule" resourceType="Unspecified" />
    </handlers>
    <aspNetCore processPath=".\MyApplication.exe" arguments="" stdoutLogEnabled="false" stdoutLogFile=".\logs\stdout" forwardWindowsAuthToken="false">
      <environmentVariables>
        <environmentVariable name="ASPNETCORE_ENVIRONMENT" value="Development" />
      </environmentVariables>
    </aspNetCore>
  </system.webServer>
</configuration>

AngularJS : Clear $watch

Ideally, every custom watch should be removed when you leave the scope.

It helps in better memory management and better app performance.

// call to $watch will return a de-register function
var listener = $scope.$watch(someVariableToWatch, function(....));

$scope.$on('$destroy', function() {
    listener(); // call the de-register function on scope destroy
});

Split page vertically using CSS

There can also be a solution by having both float to left.

Try this out:

Working Demo

P.S. This is just an improvement of Ankit's Answer

How do I set up Vim autoindentation properly for editing Python files?

A simpler option: just uncomment the following part of the configuration (which is originally commented out) in the /etc/vim/vimrc file:

    if has("autocmd")
      filetype plugin indent on
    endif

What can cause intermittent ORA-12519 (TNS: no appropriate handler found) errors

I also had the same problem, I searched for the answers many places. I got many similar answers to change the number of process/service handlers. But I thought, what if I forgot to reset it back?

Then I tried using Thread.sleep() method after each of my connection.close();.

I don't know how, but it's working at least for me.

If any one wants to try it out and figure out how it's working then please go ahead. I would also like to know it as I am a beginner in programming world.

Change mysql user password using command line

This works for me. Got solution from MYSQL webpage

In MySQL run below queries:

FLUSH PRIVILEGES;
ALTER USER 'root'@'localhost' IDENTIFIED BY 'New_Password';

How to build an APK file in Eclipse?

The simplest way to create signed/unsigned APKs using Eclipse and ADT is as follows:

Right click your project in the "Project Explorer"
Hover over "Android Tools"
Select either "Export Signed Application Package" or "Export Unsigned Application Package"
Select the location for the new APK file and click "Save".
- NOTE: If you're trying to build a APK for beta distribution, you'll probably need to create a signed package, which requires a keystore. If you follow the "Signed Application" process in Eclipse ADT it will guide you through the process of creating a new keystore.

Hope this helps.

How do I work with a git repository within another repository?

Consider using subtree instead of submodules, it will make your repo users life much easier. You may find more detailed guide in Pro Git book.

How to convert string to char array in C++?

Try strcpy(), but as Fred said, this is C++, not C

How to select the Date Picker In Selenium WebDriver

try to SendKeys instead of picking the date

driver.FindElement(yourBy).SendKeys(yourDateTime.ToString("ddd, dd.MM.yyyy",CultureInfo.CreateSpecificCulture("en-US")));

If it does not work, try to send native 'tab'

element.SendKeys(OpenQA.Selenium.Keys.Tab);

Right pad a string with variable number of spaces

This is based on Jim's answer,

SELECT
    @field_text + SPACE(@pad_length - LEN(@field_text)) AS RightPad
   ,SPACE(@pad_length - LEN(@field_text)) + @field_text AS LeftPad

Advantages

More Straight Forward
Slightly Cleaner (IMO)
Faster (Maybe?)
Easily Modified to either double pad for displaying in non-fixed width fonts or split padding left and right to center

Disadvantages

Doesn't handle LEN(@field_text) > @pad_length

SQL Server 2008: How to query all databases sizes?

with fs
as
(
    select database_id, type, size * 8.0 / 1024 size
    from sys.master_files
)
select 
    name,
    (select sum(size) from fs where type = 0 and fs.database_id = db.database_id) DataFileSizeMB,
    (select sum(size) from fs where type = 1 and fs.database_id = db.database_id) LogFileSizeMB
from sys.databases db

How to get logged-in user's name in Access vba?

In a Form, Create a text box, with in text box properties select data tab

Default value =CurrentUser()

Current source "select table field name"

It will display current user log on name in text box / label as well as saves the user name in the table field

Passing data to components in vue.js

I've found a way to pass parent data to component scope in Vue, i think it's a little a bit of a hack but maybe this will help you.

1) Reference data in Vue Instance as an external object (data : dataObj)

2) Then in the data return function in the child component just return parentScope = dataObj and voila. Now you cann do things like {{ parentScope.prop }} and will work like a charm.

Good Luck!

Can't pickle <type 'instancemethod'> when using multiprocessing Pool.map()

Some limitations though to Steven Bethard's solution :

When you register your class method as a function, the destructor of your class is surprisingly called every time your method processing is finished. So if you have 1 instance of your class that calls n times its method, members may disappear between 2 runs and you may get a message malloc: *** error for object 0x...: pointer being freed was not allocated (e.g. open member file) or pure virtual method called, terminate called without an active exception (which means than the lifetime of a member object I used was shorter than what I thought). I got this when dealing with n greater than the pool size. Here is a short example :

from multiprocessing import Pool, cpu_count
from multiprocessing.pool import ApplyResult

# --------- see Stenven's solution above -------------
from copy_reg import pickle
from types import MethodType

def _pickle_method(method):
    func_name = method.im_func.__name__
    obj = method.im_self
    cls = method.im_class
    return _unpickle_method, (func_name, obj, cls)

def _unpickle_method(func_name, obj, cls):
    for cls in cls.mro():
        try:
            func = cls.__dict__[func_name]
        except KeyError:
            pass
        else:
            break
    return func.__get__(obj, cls)


class Myclass(object):

    def __init__(self, nobj, workers=cpu_count()):

        print "Constructor ..."
        # multi-processing
        pool = Pool(processes=workers)
        async_results = [ pool.apply_async(self.process_obj, (i,)) for i in range(nobj) ]
        pool.close()
        # waiting for all results
        map(ApplyResult.wait, async_results)
        lst_results=[r.get() for r in async_results]
        print lst_results

    def __del__(self):
        print "... Destructor"

    def process_obj(self, index):
        print "object %d" % index
        return "results"

pickle(MethodType, _pickle_method, _unpickle_method)
Myclass(nobj=8, workers=3)
# problem !!! the destructor is called nobj times (instead of once)

Output:

Constructor ...
object 0
object 1
object 2
... Destructor
object 3
... Destructor
object 4
... Destructor
object 5
... Destructor
object 6
... Destructor
object 7
... Destructor
... Destructor
... Destructor
['results', 'results', 'results', 'results', 'results', 'results', 'results', 'results']
... Destructor

The __call__ method is not so equivalent, because [None,...] are read from the results :

from multiprocessing import Pool, cpu_count
from multiprocessing.pool import ApplyResult

class Myclass(object):

    def __init__(self, nobj, workers=cpu_count()):

        print "Constructor ..."
        # multiprocessing
        pool = Pool(processes=workers)
        async_results = [ pool.apply_async(self, (i,)) for i in range(nobj) ]
        pool.close()
        # waiting for all results
        map(ApplyResult.wait, async_results)
        lst_results=[r.get() for r in async_results]
        print lst_results

    def __call__(self, i):
        self.process_obj(i)

    def __del__(self):
        print "... Destructor"

    def process_obj(self, i):
        print "obj %d" % i
        return "result"

Myclass(nobj=8, workers=3)
# problem !!! the destructor is called nobj times (instead of once), 
# **and** results are empty !

So none of both methods is satisfying...

Access Https Rest Service using Spring RestTemplate

Here is what I ended up with for the similar problem. The idea is the same as in @Avi's answer, but I also wanted to avoid the static "System.setProperty("https.protocols", "TLSv1");", so that any adjustments won't affect the system. Inspired by an answer from here http://www.coderanch.com/t/637177/Security/Disabling-handshake-message-Java

public class MyCustomClientHttpRequestFactory extends SimpleClientHttpRequestFactory {

@Override
protected void prepareConnection(HttpURLConnection connection, String httpMethod) {
    try {
        if (!(connection instanceof HttpsURLConnection)) {
            throw new RuntimeException("An instance of HttpsURLConnection is expected");
        }

        HttpsURLConnection httpsConnection = (HttpsURLConnection) connection;

        TrustManager[] trustAllCerts = new TrustManager[]{
                new X509TrustManager() {
                    public java.security.cert.X509Certificate[] getAcceptedIssuers() {
                        return null;
                    }

                    public void checkClientTrusted(X509Certificate[] certs, String authType) {
                    }

                    public void checkServerTrusted(X509Certificate[] certs, String authType) {
                    }

                }
        };
        SSLContext sslContext = SSLContext.getInstance("SSL");
        sslContext.init(null, trustAllCerts, new java.security.SecureRandom());
        httpsConnection.setSSLSocketFactory(new MyCustomSSLSocketFactory(sslContext.getSocketFactory()));

        httpsConnection.setHostnameVerifier((hostname, session) -> true);

        super.prepareConnection(httpsConnection, httpMethod);
    } catch (Exception e) {
        throw Throwables.propagate(e);
    }
}

/**
 * We need to invoke sslSocket.setEnabledProtocols(new String[] {"SSLv3"});
 * see http://www.oracle.com/technetwork/java/javase/documentation/cve-2014-3566-2342133.html (Java 8 section)
 */
private static class MyCustomSSLSocketFactory extends SSLSocketFactory {

    private final SSLSocketFactory delegate;

    public MyCustomSSLSocketFactory(SSLSocketFactory delegate) {
        this.delegate = delegate;
    }

    @Override
    public String[] getDefaultCipherSuites() {
        return delegate.getDefaultCipherSuites();
    }

    @Override
    public String[] getSupportedCipherSuites() {
        return delegate.getSupportedCipherSuites();
    }

    @Override
    public Socket createSocket(final Socket socket, final String host, final int port, final boolean autoClose) throws IOException {
        final Socket underlyingSocket = delegate.createSocket(socket, host, port, autoClose);
        return overrideProtocol(underlyingSocket);
    }

    @Override
    public Socket createSocket(final String host, final int port) throws IOException {
        final Socket underlyingSocket = delegate.createSocket(host, port);
        return overrideProtocol(underlyingSocket);
    }

    @Override
    public Socket createSocket(final String host, final int port, final InetAddress localAddress, final int localPort) throws IOException {
        final Socket underlyingSocket = delegate.createSocket(host, port, localAddress, localPort);
        return overrideProtocol(underlyingSocket);
    }

    @Override
    public Socket createSocket(final InetAddress host, final int port) throws IOException {
        final Socket underlyingSocket = delegate.createSocket(host, port);
        return overrideProtocol(underlyingSocket);
    }

    @Override
    public Socket createSocket(final InetAddress host, final int port, final InetAddress localAddress, final int localPort) throws IOException {
        final Socket underlyingSocket = delegate.createSocket(host, port, localAddress, localPort);
        return overrideProtocol(underlyingSocket);
    }

    private Socket overrideProtocol(final Socket socket) {
        if (!(socket instanceof SSLSocket)) {
            throw new RuntimeException("An instance of SSLSocket is expected");
        }
        ((SSLSocket) socket).setEnabledProtocols(new String[] {"SSLv3"});
        return socket;
    }
}
}

Convert form data to JavaScript object with jQuery

The serialize function take JSON object as a parameter and return serialize String.

function serialize(object) {
            var _SPECIAL_CHARS = /[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g, _CHARS = {
                '\b' : '\\b',
                '\t' : '\\t',
                '\n' : '\\n',
                '\f' : '\\f',
                '\r' : '\\r',
                '"' : '\\"',
                '\\' : '\\\\'
            }, EMPTY = '', OPEN_O = '{', CLOSE_O = '}', OPEN_A = '[', CLOSE_A = ']', COMMA = ',', COMMA_CR = ",\n", CR = "\n", COLON = ':', space = "", COLON_SP = ': ', stack = [], QUOTE = '"';
            function _char(c) {
                if (!_CHARS[c]) {
                    _CHARS[c] = '\\u' + ('0000' + (+(c.charCodeAt(0))).toString(16))
                        .slice(-4);
                }
                return _CHARS[c];
            }
            function _string(s) {
                return QUOTE + s.replace(_SPECIAL_CHARS, _char) + QUOTE;
                // return str.replace('\"','').replace('\"','');
            }

            function serialize(h, key) {
                var value = h[key], a = [], colon = ":", arr, i, keys, t, k, v;
                arr = value instanceof Array;
                stack.push(value);
                keys = value;
                i = 0;
                t = typeof value;
                switch (t) {
                    case "object" :
                        if(value==null){
                            return null;
                        }
                        break;
                    case "string" :
                        return _string(value);
                    case "number" :
                        return isFinite(value) ? value + EMPTY : NULL;
                    case "boolean" :
                        return value + EMPTY;
                    case "null" :
                        return null;
                    default :
                        return undefined;
                }
                arr = value.length === undefined ? false : true;

                if (arr) { // Array
                    for (i = value.length - 1; i >= 0; --i) {
                        a[i] = serialize(value, i) || NULL;
                    }
                }
                else { // Object
                    i = 0;
                    for (k in keys) {
                        if (keys.hasOwnProperty(k)) {
                            v = serialize(value, k);
                            if (v) {
                                a[i++] = _string(k) + colon + v;
                            }
                        }
                    }
                }

                stack.pop();
                if (space && a.length) {

                    return arr
                        ? "[" + _indent(a.join(COMMA_CR), space) + "\n]"
                        : "{\n" + _indent(a.join(COMMA_CR), space) + "\n}";
                }
                else {
                    return arr ? "[" + a.join(COMMA) + "]" : "{" + a.join(COMMA)
                        + "}";
                }
            }
            return serialize({
                "" : object
            }, "");
        }

How to include files outside of Docker's build context?

Using docker-compose, I accomplished this by creating a service that mounts the volumes that I need and committing the image of the container. Then, in the subsequent service, I rely on the previously committed image, which has all of the data stored at mounted locations. You will then have have to copy these files to their ultimate destination, as host mounted directories do not get committed when running a docker commit command

You don't have to use docker-compose to accomplish this, but it makes life a bit easier

# docker-compose.yml

version: '3'
  services:
    stage:
      image: alpine
      volumes:
        - /host/machine/path:/tmp/container/path
      command: bash -c "cp -r /tmp/container/path /final/container/path"
    setup:
      image: stage

# setup.sh

# Start "stage" service
docker-compose up stage

# Commit changes to an image named "stage"
docker commit $(docker-compose ps -q stage) stage

# Start setup service off of stage image
docker-compose up setup

Detect the Internet connection is offline?

The problem of some methods like navigator.onLine is that they are not compatible with some browsers and mobile versions, an option that helped me a lot was to use the classic XMLHttpRequest method and also foresee the possible case that the file was stored in cache with response XMLHttpRequest.status is greater than 200 and less than 304.

Here is my code:

 var xhr = new XMLHttpRequest();
 //index.php is in my web
 xhr.open('HEAD', 'index.php', true);
 xhr.send();

 xhr.addEventListener("readystatechange", processRequest, false);

 function processRequest(e) {
     if (xhr.readyState == 4) {
         //If you use a cache storage manager (service worker), it is likely that the
         //index.php file will be available even without internet, so do the following validation
         if (xhr.status >= 200 && xhr.status < 304) {
             console.log('On line!');
         } else {
             console.log('Offline :(');
         }
     }
}

Import one schema into another new schema - Oracle

After you correct the possible dmp file problem, this is a way to ensure that the schema is remapped and imported appropriately. This will also ensure that the tablespace will change also, if needed:

impdp system/<password> SCHEMAS=user1 remap_schema=user1:user2 \
            remap_tablespace=user1:user2 directory=EXPORTDIR \
            dumpfile=user1.dmp logfile=E:\Data\user1.log

EXPORTDIR must be defined in oracle as a directory as the system user

create or replace directory EXPORTDIR as 'E:\Data';
grant read, write on directory EXPORTDIR to user2;

Java ByteBuffer to String

The answers referring to simply calling array() are not quite correct: when the buffer has been partially consumed, or is referring to a part of an array (you can ByteBuffer.wrap an array at a given offset, not necessarily from the beginning), we have to account for that in our calculations. This is the general solution that works for buffers in all cases (does not cover encoding):

if (myByteBuffer.hasArray()) {
    return new String(myByteBuffer.array(),
        myByteBuffer.arrayOffset() + myByteBuffer.position(),
        myByteBuffer.remaining());
} else {
    final byte[] b = new byte[myByteBuffer.remaining()];
    myByteBuffer.duplicate().get(b);
    return new String(b);
}

For the concerns related to encoding, see Andy Thomas' answer.

How to Resize image in Swift?

For Swift 4 I would just make an extension on UIImage with referencing to self.

import UIKit
extension UIImage {
  func resizeImage(targetSize: CGSize) -> UIImage {
    let size = self.size
    let widthRatio  = targetSize.width  / size.width
    let heightRatio = targetSize.height / size.height
    let newSize = widthRatio > heightRatio ?  CGSize(width: size.width * heightRatio, height: size.height * heightRatio) : CGSize(width: size.width * widthRatio,  height: size.height * widthRatio)
    let rect = CGRect(x: 0, y: 0, width: newSize.width, height: newSize.height)

    UIGraphicsBeginImageContextWithOptions(newSize, false, 1.0)
    self.draw(in: rect)
    let newImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()

    return newImage!
  }
}

Programmatically add new column to DataGridView

Keep it simple

dataGridView1.Columns.Add("newColumnName", "Column Name in Text");

To add rows

dataGridView1.Rows.Add("Value for column#1"); // [,"column 2",...]

npm install vs. update - what's the difference?

Many distinctions have already been mentioned. Here is one more:

Running npm install at the top of your source directory will run various scripts: prepublish, preinstall, install, postinstall. Depending on what these scripts do, a npm install may do considerably more work than just installing dependencies.

I've just had a use case where prepublish would call make and the Makefile was designed to fetch dependencies if the package.json got updated. Calling npm install from within the Makefile would have lead to an infinite recursion, while calling npm update worked just fine, installing all dependencies so that the build could proceed even if make was called directly.

org.postgresql.util.PSQLException: FATAL: sorry, too many clients already

The offending lines are the following:

MaxConnections=90
InitialConnections=80

You can increase the values to allow more connections.

Generate Json schema from XML schema (XSD)

Copy your XML schema here & get the JSON schema code to the online tools which are available to generate JSON schema from XML schema.

failed to load ad : 3

Don't forget to add payment methods on Google AdMod. It was my issue with "Error code 3". Anyway, when your account Google AdMod will be ready to show ads (for tested device or real users) they send you email that your account verified and ready to work! After this letter everything should work fine.

Programs & Examples On #Chronic

upstream sent too big header while reading response header from upstream

Plesk instructions

Bundler::GemNotFound: Could not find rake-10.3.2 in any of the sources

Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference

how to use json file in html code

How to start rails server?

For newest Rails versions

Ruby String to Date Conversion

Do copyright dates need to be updated?

Leave only two decimal places after the dot

Update TextView Every Second

Limit file format when using <input type="file">?

How do I do a HTTP GET in Java?

How to concatenate properties from multiple JavaScript objects

Get URL query string parameters

JSON Parse File Path

Could not load file or assembly Microsoft.SqlServer.management.sdk.sfc version 11.0.0.0

How can I start an interactive console for Perl?

Calculating the distance between 2 points

Adding header for HttpURLConnection

Relative Paths in Javascript in an external file

How to create an array containing 1...N

Print text instead of value from C enum

How to sort an associative array by its values in Javascript?

Use SQL Server Management Studio to connect remotely to an SQL Server Express instance hosted on an Azure Virtual Machine

How to delete only the content of file in python

Retrieve the maximum length of a VARCHAR column in SQL Server

Using PropertyInfo.GetValue()

How to rename with prefix/suffix?

How are parameters sent in an HTTP POST request?

GET (relevant RFC section)

POST (relevant RFC section)

PUT (relevant RFC section)

Side-Note

Fast ceiling of an integer division in C / C++

How to change package name in flutter?

org.xml.sax.SAXParseException: Premature end of file for *VALID* XML

How can I set a cookie in react?

Return file in ASP.Net Core Web API

Java - get pixel array from image

What are static factory methods?

Get current cursor position in a textbox

Websocket onerror - how to read error description?

Speed tradeoff of Java's -Xms and -Xmx options

How to select a record and update it, with a single queryset in Django?

Is the sizeof(some pointer) always equal to four?

How to render html with AngularJS templates

Node.js get file extension

Static class initializer in PHP

Shell equality operators (=, ==, -eq)

Asp.net Validation of viewstate MAC failed

How to execute XPath one-liners from shell?

In MVC, how do I return a string result?

ConcurrentModificationException for ArrayList

Vibrate and Sound defaults on notification

How do I install imagemagick with homebrew?

How to tell if a <script> tag failed to load

Force browser to download image files on click

How to limit the maximum files chosen when using multiple file input

How do I move a file from one location to another in Java?

How can I display just a portion of an image in HTML/CSS?

Initialize class fields in constructor or at declaration?

Factorial using Recursion in Java

How to get the SHA-1 fingerprint certificate in Android Studio for debug mode?

How to define custom configuration variables in rails

Get img src with PHP

C# send a simple SSH command

Displaying a message in iOS which has the same functionality as Toast in Android

Convert factor to integer

Sending XML data using HTTP POST with PHP

Search for highest key/index in an array

Looping through a hash, or using an array in PowerShell

Get top 1 row of each group

PostgreSQL how to see which queries have run

How do I get interactive plots again in Spyder/IPython/matplotlib?

Ruby on Rails. How do I use the Active Record .build method in a :belongs to relationship?

List of Python format characters

Where Sticky Notes are saved in Windows 10 1607

How to set the timeout for a TcpClient?

org.xml.sax.SAXParseException: Premature end of file for VALID XML