Programs & Examples On #Jikes

Jikes is a Java compiler, first released in April 1997 on the IBM and currently open source.

How to initialize log4j properly?

You can set up the log level by using setLevel().

The levels are useful to easily set the kind of informations you want the program to display.

For example:

Logger.getRootLogger().setLevel(Level.WARN); //will not show debug messages

The set of possible levels are:

TRACE,

DEBUG,

INFO,

WARN,

ERROR and

FATAL

According to Logging Services manual

ASP.NET Custom Validator Client side & Server Side validation not firing

Client-side validation was not being executed at all on my web form and I had no idea why. It turns out the problem was the name of the javascript function was the same as the server control ID.

So you can't do this...

<script>
  function vld(sender, args) { args.IsValid = true; }
</script>
<asp:CustomValidator runat="server" id="vld" ClientValidationFunction="vld" />

But this works:

<script>
  function validate_vld(sender, args) { args.IsValid = true; }
</script>
<asp:CustomValidator runat="server" id="vld" ClientValidationFunction="validate_vld" />

I'm guessing it conflicts with internal .NET Javascript?

How to control the width of select tag?

You've simply got it backwards. Specifying a minimum width would make the select menu always be at least that width, so it will continue expanding to 90% no matter what the window size is, also being at least the size of its longest option.

You need to use max-width instead. This way, it will let the select menu expand to its longest option, but if that expands past your set maximum of 90% width, crunch it down to that width.

Posting JSON Data to ASP.NET MVC

You can try these. 1. stringify your JSON Object before calling the server action via ajax 2. deserialize the string in the action then use the data as a dictionary.

Javascript sample below (sending the JSON Object

$.ajax(
   {
       type: 'POST',
       url: 'TheAction',
       data: { 'data': JSON.stringify(theJSONObject) 
   }
})

Action (C#) sample below

[HttpPost]
public JsonResult TheAction(string data) {

       string _jsonObject = data.Replace(@"\", string.Empty);
       var serializer = new System.Web.Script.Serialization.JavaScriptSerializer();           
        Dictionary<string, string> jsonObject = serializer.Deserialize<Dictionary<string, string>>(_jsonObject);


        return Json(new object{status = true});

    }

do { ... } while (0) — what is it good for?

It helps to group multiple statements into a single one so that a function-like macro can actually be used as a function. Suppose you have:

#define FOO(n)   foo(n);bar(n)

and you do:

void foobar(int n) {
  if (n)
     FOO(n);
}

then this expands to:

void foobar(int n) {
  if (n)
     foo(n);bar(n);
}

Notice that the second call bar(n) is not part of the if statement anymore.

Wrap both into do { } while(0), and you can also use the macro in an if statement.

How do I pull files from remote without overwriting local files?

So you have committed your local changes to your local repository. Then in order to get remote changes to your local repository without making changes to your local files, you can use git fetch. Actually git pull is a two step operation: a non-destructive git fetch followed by a git merge. See What is the difference between 'git pull' and 'git fetch'? for more discussion.

Detailed example:

Suppose your repository is like this (you've made changes test2:

* ed0bcb2 - (HEAD, master) test2
* 4942854 - (origin/master, origin/HEAD) first

And the origin repository is like this (someone else has committed test1):

* 5437ca5 - (HEAD, master) test1
* 4942854 - first

At this point of time, git will complain and ask you to pull first if you try to push your test2 to remote repository. If you want to see what test1 is without modifying your local repository, run this:

$ git fetch

Your result local repository would be like this:

* ed0bcb2 - (HEAD, master) test2 
| * 5437ca5 - (origin/master, origin/HEAD) test1 
|/  
* 4942854 - first 

Now you have the remote changes in another branch, and you keep your local files intact.

Then what's next? You can do a git merge, which will be the same effect as git pull (when combined with the previous git fetch), or, as I would prefer, do a git rebase origin/master to apply your change on top of origin/master, which gives you a cleaner history.

function declaration isn't a prototype

In C int foo() and int foo(void) are different functions. int foo() accepts an arbitrary number of arguments, while int foo(void) accepts 0 arguments. In C++ they mean the same thing. I suggest that you use void consistently when you mean no arguments.

If you have a variable a, extern int a; is a way to tell the compiler that a is a symbol that might be present in a different translation unit (C compiler speak for source file), don't resolve it until link time. On the other hand, symbols which are function names are anyway resolved at link time. The meaning of a storage class specifier on a function (extern, static) only affects its visibility and extern is the default, so extern is actually unnecessary.

I suggest removing the extern, it is extraneous and is usually omitted.

Table with fixed header and fixed column on pure css

An actual pure CSS solution with a fixed header row and first column

I had to create a table with both a fixed header and a fixed first column using pure CSS and none of the answers here were quite what I wanted.

The position: sticky property supports both sticking to the top (as I've seen it used the most) and to the side in modern versions of Chrome, Firefox, and Edge. This can be combined with a div that has the overflow: scroll property to give you a table with fixed headers that can be placed anywhere on your page:

Place your table in a container:

<div class="container">
  <table></table>
</div>

Use overflow: scroll on your container to enable scrolling:

div.container {
  overflow: scroll;
}

As Dagmar pointed out in the comments, the container also requires a max-width and a max-height.

Use position: sticky to have table cells stick to the edge and top, right, or left to choose which edge to stick to:

thead th {
  position: -webkit-sticky; /* for Safari */
  position: sticky;
  top: 0;
}

tbody th {
  position: -webkit-sticky; /* for Safari */
  position: sticky;
  left: 0;
}

As MarredCheese mentioned in the comments, if your first column contains <td> elements instead of <th> elements, you can use tbody td:first-child in your CSS instead of tbody th

To have the header in the first column stick to the left, use:

thead th:first-child {
  left: 0;
  z-index: 1;
}

_x000D_
_x000D_
/* Use overflow:scroll on your container to enable scrolling: */

div {
  max-width: 400px;
  max-height: 150px;
  overflow: scroll;
}


/* Use position: sticky to have it stick to the edge
 * and top, right, or left to choose which edge to stick to: */

thead th {
  position: -webkit-sticky; /* for Safari */
  position: sticky;
  top: 0;
}

tbody th {
  position: -webkit-sticky; /* for Safari */
  position: sticky;
  left: 0;
}


/* To have the header in the first column stick to the left: */

thead th:first-child {
  left: 0;
  z-index: 2;
}


/* Just to display it nicely: */

thead th {
  background: #000;
  color: #FFF;
  /* Ensure this stays above the emulated border right in tbody th {}: */
  z-index: 1;
}

tbody th {
  background: #FFF;
  border-right: 1px solid #CCC;
  /* Browsers tend to drop borders on sticky elements, so we emulate the border-right using a box-shadow to ensure it stays: */
  box-shadow: 1px 0 0 0 #ccc;
}

table {
  border-collapse: collapse;
}

td,
th {
  padding: 0.5em;
}
_x000D_
<div>
  <table>
    <thead>
      <tr>
        <th></th>
        <th>headheadhead</th>
        <th>headheadhead</th>
        <th>headheadhead</th>
        <th>headheadhead</th>
        <th>headheadhead</th>
        <th>headheadhead</th>
        <th>headheadhead</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
      <tr>
        <th>head</th>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
        <td>body</td>
      </tr>
    </tbody>
  </table>
</div>
_x000D_
_x000D_
_x000D_

https://jsfiddle.net/qwubvg9m/1/

Removing duplicate rows from table in Oracle

Solution 1)

delete from emp
where rowid not in
(select max(rowid) from emp group by empno);

Solution 2)

delete from emp where rowid in
               (
                 select rid from
                  (
                    select rowid rid,
                      row_number() over(partition by empno order by empno) rn
                      from emp
                  )
                where rn > 1
               );

Solution 3)

delete from emp e1
         where rowid not in
          (select max(rowid) from emp e2
           where e1.empno = e2.empno ); 

React with ES7: Uncaught TypeError: Cannot read property 'state' of undefined

Make sure you're calling super() as the first thing in your constructor.

You should set this for setAuthorState method

class ManageAuthorPage extends Component {

  state = {
    author: { id: '', firstName: '', lastName: '' }
  };

  constructor(props) {
    super(props);
    this.handleAuthorChange = this.handleAuthorChange.bind(this);
  } 

  handleAuthorChange(event) {
    let {name: fieldName, value} = event.target;

    this.setState({
      [fieldName]: value
    });
  };

  render() {
    return (
      <AuthorForm
        author={this.state.author}
        onChange={this.handleAuthorChange}
      />
    );
  }
}

Another alternative based on arrow function:

class ManageAuthorPage extends Component {

  state = {
    author: { id: '', firstName: '', lastName: '' }
  };

  handleAuthorChange = (event) => {
    const {name: fieldName, value} = event.target;

    this.setState({
      [fieldName]: value
    });
  };

  render() {
    return (
      <AuthorForm
        author={this.state.author}
        onChange={this.handleAuthorChange}
      />
    );
  }
}

Java Best Practices to Prevent Cross Site Scripting

The normal practice is to HTML-escape any user-controlled data during redisplaying in JSP, not during processing the submitted data in servlet nor during storing in DB. In JSP you can use the JSTL (to install it, just drop jstl-1.2.jar in /WEB-INF/lib) <c:out> tag or fn:escapeXml function for this. E.g.

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
...
<p>Welcome <c:out value="${user.name}" /></p>

and

<%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
...
<input name="username" value="${fn:escapeXml(param.username)}">

That's it. No need for a blacklist. Note that user-controlled data covers everything which comes in by a HTTP request: the request parameters, body and headers(!!).

If you HTML-escape it during processing the submitted data and/or storing in DB as well, then it's all spread over the business code and/or in the database. That's only maintenance trouble and you will risk double-escapes or more when you do it at different places (e.g. & would become &amp;amp; instead of &amp; so that the enduser would literally see &amp; instead of & in view. The business code and DB are in turn not sensitive for XSS. Only the view is. You should then escape it only right there in view.

See also:

How do I get a value of a <span> using jQuery?

VERY IMPORTANT Additional info on difference between .text() and .html():

If your selector selects more than one item, e.g you have two spans like so <span class="foo">bar1</span> <span class="foo">bar2</span> ,

then

$('.foo').text(); appends the two texts and give you that; whereas

$('.foo').html(); gives you only one of those.

Simple example of threading in C++

#include <thread>
#include <iostream>
#include <vector>
using namespace std;

void doSomething(int id) {
    cout << id << "\n";
}

/**
 * Spawns n threads
 */
void spawnThreads(int n)
{
    std::vector<thread> threads(n);
    // spawn n threads:
    for (int i = 0; i < n; i++) {
        threads[i] = thread(doSomething, i + 1);
    }

    for (auto& th : threads) {
        th.join();
    }
}

int main()
{
    spawnThreads(10);
}

Search and replace a line in a file in Python

Here's another example that was tested, and will match search & replace patterns:

import fileinput
import sys

def replaceAll(file,searchExp,replaceExp):
    for line in fileinput.input(file, inplace=1):
        if searchExp in line:
            line = line.replace(searchExp,replaceExp)
        sys.stdout.write(line)

Example use:

replaceAll("/fooBar.txt","Hello\sWorld!$","Goodbye\sWorld.")

Pass by pointer & Pass by reference

Here is a good article on the matter - "Use references when you can, and pointers when you have to."

How can I pass variable to ansible playbook in the command line?

ansible-playbook release.yml -e "version=1.23.45 other_variable=foo"

Get file version in PowerShell

Since PowerShell can call .NET classes, you could do the following:

[System.Diagnostics.FileVersionInfo]::GetVersionInfo("somefilepath").FileVersion

Or as noted here on a list of files:

get-childitem * -include *.dll,*.exe | foreach-object { "{0}`t{1}" -f $_.Name, [System.Diagnostics.FileVersionInfo]::GetVersionInfo($_).FileVersion }

Or even nicer as a script: https://jtruher3.wordpress.com/2006/05/14/powershell-and-file-version-information/

Div Scrollbar - Any way to style it?

Using javascript you can style the scroll bars. Which works fine in IE as well as FF.

Check the below links

From Twinhelix , Example 2 , Example 3 [or] you can find some 30 type of scroll style types by click the below link 30 scrolling techniques

How to define constants in ReactJS

Warning: this is an experimental feature that could dramatically change or even cease to exist in future releases

You can use ES7 statics:

npm install babel-preset-stage-0

And then add "stage-0" to .babelrc presets:

{
    "presets": ["es2015", "react", "stage-0"]
}

Afterwards, you go

class Component extends React.Component {
    static foo = 'bar';
    static baz = {a: 1, b: 2}
}

And then you use them like this:

Component.foo

How to overcome root domain CNAME restrictions?

I don't know how they are getting away with it, or what negative side effects their may be, but I'm using Hover.com to host some of my domains, and recently setup the apex of my domain as a CNAME there. Their DNS editing tool did not complain at all, and my domain happily resolves via the CNAME assigned.

Here is what Dig shows me for this domain (actual domain obfuscated as mydomain.com):

; <<>> DiG 9.8.3-P1 <<>> mydomain.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2056
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;mydomain.com.          IN  A

;; ANSWER SECTION:
mydomain.com.       394 IN  CNAME   myapp.parseapp.com.
myapp.parseapp.com. 300 IN  CNAME   parseapp.com.
parseapp.com.       60  IN  A   54.243.93.102

Git commit date

if you got troubles with windows cmd command and .bat just escape percents like that

git show -s --format=%%ct

The % character has a special meaning for command line parameters and FOR parameters. To treat a percent as a regular character, double it: %%

Syntax : Escape Characters, Delimiters and Quotes

Global Git ignore

  1. Create a .gitignore file in your home directory
touch ~/.gitignore
  1. Add files to it (folders aren't recognised)

Example

# these work
*.gz
*.tmproj
*.7z

# these won't as they are folders
.vscode/
build/

# but you can do this
.vscode/*
build/*
  1. Check if a git already has a global gitignore
git config --get core.excludesfile
  1. Tell git where the file is
git config --global core.excludesfile '~/.gitignore'

Voila!!

How link to any local file with markdown syntax?

After messing around with @BringBackCommodore64 answer I figured it out

[link](file:///d:/absolute.md)    # absolute filesystem path
[link](./relative1.md)            # relative to opened file
[link](/relativeToProject.md)     # relative to opened project

All of them tested in Visual Studio Code and working,

Note: The absolute path works in editor but doesn't work in markdown preview mode!

Trim to remove white space

jQuery.trim() capital Q?

or $.trim()

Run automatically program on startup under linux ubuntu

sudo mv /filename /etc/init.d/
sudo chmod +x /etc/init.d/filename 
sudo update-rc.d filename defaults 

Script should now start on boot. Note that this method also works with both hard links and symbolic links (ln).

Edit

At this point in the boot process PATH isn't set yet, so it is critical that absolute paths are used throughout. BUT, as pointed out in the comments by Steve HHH, explicitly declaring the full file path (/etc/init.d/filename) for the update-rc.d command is not valid in most versions of Linux. Per the manpage for update-rc.d, the second parameter is a script located in /etc/init.d/*. Updated above code to reflect this.

Another Edit

Also as pointed out in the comments (by Charles Brandt), /filename must be an init style script. A good template was also provided - https://github.com/fhd/init-script-template.

Another link to another article just to avoid possible link rot (although it would be saddening if GitHub died) - http://www.linux.com/learn/tutorials/442412-managing-linux-daemons-with-init-scripts

yetAnother Edit

As pointed out in the comments (by Russell Yan), This works only on default mode of update-rc.d.

According to manual of update-rc.d, it can run on two modes, "the machines using the legacy mode will have a file /etc/init.d/.legacy-bootordering", in which case you have to pass sequence and runlevel configuration through command line arguments.

The equivalent argument set for the above example is

sudo update-rc.d filename start 20 2 3 4 5 . stop 20 0 1 6 .

toggle show/hide div with button?

Look at jQuery Toggle

HTML:

<div id='content'>Hello World</div>
<input type='button' id='hideshow' value='hide/show'>

jQuery:

jQuery(document).ready(function(){
    jQuery('#hideshow').live('click', function(event) {        
         jQuery('#content').toggle('show');
    });
});

For versions of jQuery 1.7 and newer use

jQuery(document).ready(function(){
    jQuery('#hideshow').on('click', function(event) {        
        jQuery('#content').toggle('show');
    });
});

For reference, kindly check this demo

Visual Studio Code: format is not using indent settings

For myself, this problem was caused by using the prettier VSCode plugin without having a prettier config file in the workspace.

Disabling the plugin fixed the problem. It could have also probably been fixed by relying on the prettier config.

How to deploy a war file in JBoss AS 7?

Read the file $AS/standalone/deployments/README.txt

  • you have two different modes : auto-deploy mode and manual deploy mode
  • for the manual deploy mode you have to placed a marker files as described in the others posts
  • for the autodeploy mode : This is done via the "auto-deploy" attributes on the deployment-scanner element in the standalone.xml configuration file:

    <deployment-scanner scan-interval="5000" relative-to="jboss.server.base.dir"
    path="deployments" auto-deploy-zipped="true" **auto-deploy-exploded="true"**/>
    

Best timing method in C?

High resolution is relative... I was looking at the examples and they mostly cater for milliseconds. However for me it is important to measure microseconds. I have not seen a platform independant solution for microseconds and thought something like the code below will be usefull. I was timing on windows only for the time being and will most likely add a gettimeofday() implementation when doing the same on AIX/Linux.

    #ifdef WIN32
      #ifndef PERFTIME
        #include <windows.h>
        #include <winbase.h>
        #define PERFTIME_INIT unsigned __int64 freq;  QueryPerformanceFrequency((LARGE_INTEGER*)&freq); double timerFrequency = (1.0/freq);  unsigned __int64 startTime;  unsigned __int64 endTime;  double timeDifferenceInMilliseconds;
        #define PERFTIME_START QueryPerformanceCounter((LARGE_INTEGER *)&startTime);
        #define PERFTIME_END QueryPerformanceCounter((LARGE_INTEGER *)&endTime); timeDifferenceInMilliseconds = ((endTime-startTime) * timerFrequency);  printf("Timing %fms\n",timeDifferenceInMilliseconds);
    #define PERFTIME(funct) {unsigned __int64 freq;  QueryPerformanceFrequency((LARGE_INTEGER*)&freq);  double timerFrequency = (1.0/freq);  unsigned __int64 startTime;  QueryPerformanceCounter((LARGE_INTEGER *)&startTime);  unsigned __int64 endTime;  funct; QueryPerformanceCounter((LARGE_INTEGER *)&endTime);  double timeDifferenceInMilliseconds = ((endTime-startTime) * timerFrequency);  printf("Timing %fms\n",timeDifferenceInMilliseconds);}
      #endif
    #else
      //AIX/Linux gettimeofday() implementation here
    #endif

Usage:

PERFTIME(ProcessIntenseFunction());

or

PERFTIME_INIT
PERFTIME_START
ProcessIntenseFunction()
PERFTIME_END

encrypt and decrypt md5

It's not possible to decrypt MD5 hash which created. You need all information to decrypt the MD5 value which was used during encryption.

You can use AES algorithm to encrypt and decrypt

JavaScript AES encryption and decryption (Advanced Encryption Standard)

How do I make calls to a REST API using C#?

The ASP.NET Web API has replaced the WCF Web API previously mentioned.

I thought I'd post an updated answer since most of these responses are from early 2012, and this thread is one of the top results when doing a Google search for "call restful service C#".

Current guidance from Microsoft is to use the Microsoft ASP.NET Web API Client Libraries to consume a RESTful service. This is available as a NuGet package, Microsoft.AspNet.WebApi.Client. You will need to add this NuGet package to your solution.

Here's how your example would look when implemented using the ASP.NET Web API Client Library:

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;

namespace ConsoleProgram
{
    public class DataObject
    {
        public string Name { get; set; }
    }

    public class Class1
    {
        private const string URL = "https://sub.domain.com/objects.json";
        private string urlParameters = "?api_key=123";

        static void Main(string[] args)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri(URL);

            // Add an Accept header for JSON format.
            client.DefaultRequestHeaders.Accept.Add(
            new MediaTypeWithQualityHeaderValue("application/json"));

            // List data response.
            HttpResponseMessage response = client.GetAsync(urlParameters).Result;  // Blocking call! Program will wait here until a response is received or a timeout occurs.
            if (response.IsSuccessStatusCode)
            {
                // Parse the response body.
                var dataObjects = response.Content.ReadAsAsync<IEnumerable<DataObject>>().Result;  //Make sure to add a reference to System.Net.Http.Formatting.dll
                foreach (var d in dataObjects)
                {
                    Console.WriteLine("{0}", d.Name);
                }
            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }

            // Make any other calls using HttpClient here.

            // Dispose once all HttpClient calls are complete. This is not necessary if the containing object will be disposed of; for example in this case the HttpClient instance will be disposed automatically when the application terminates so the following call is superfluous.
            client.Dispose();
        }
    }
}

If you plan on making multiple requests, you should re-use your HttpClient instance. See this question and its answers for more details on why a using statement was not used on the HttpClient instance in this case: Do HttpClient and HttpClientHandler have to be disposed between requests?

For more details, including other examples, see Call a Web API From a .NET Client (C#)

This blog post may also be useful: Using HttpClient to Consume ASP.NET Web API REST Services

How to use ng-repeat without an html element

Update: If you are using Angular 1.2+, use ng-repeat-start. See @jmagnusson's answer.

Otherwise, how about putting the ng-repeat on tbody? (AFAIK, it is okay to have multiple <tbody>s in a single table.)

<tbody ng-repeat="row in array">
  <tr ng-repeat="item in row">
     <td>{{item}}</td>
  </tr>
</tbody>

What is the difference between _tmain() and main() in C++?

_tmain is a macro that gets redefined depending on whether or not you compile with Unicode or ASCII. It is a Microsoft extension and isn't guaranteed to work on any other compilers.

The correct declaration is

 int _tmain(int argc, _TCHAR *argv[]) 

If the macro UNICODE is defined, that expands to

int wmain(int argc, wchar_t *argv[])

Otherwise it expands to

int main(int argc, char *argv[])

Your definition goes for a bit of each, and (if you have UNICODE defined) will expand to

 int wmain(int argc, char *argv[])

which is just plain wrong.

std::cout works with ASCII characters. You need std::wcout if you are using wide characters.

try something like this

#include <iostream>
#include <tchar.h>

#if defined(UNICODE)
    #define _tcout std::wcout
#else
    #define _tcout std::cout
#endif

int _tmain(int argc, _TCHAR *argv[]) 
{
   _tcout << _T("There are ") << argc << _T(" arguments:") << std::endl;

   // Loop through each argument and print its number and value
   for (int i=0; i<argc; i++)
      _tcout << i << _T(" ") << argv[i] << std::endl;

   return 0;
}

Or you could just decide in advance whether to use wide or narrow characters. :-)

Updated 12 Nov 2013:

Changed the traditional "TCHAR" to "_TCHAR" which seems to be the latest fashion. Both work fine.

End Update

How do I install a custom font on an HTML site

there is a simple way to do this: in the html file add:

<link rel="stylesheet" href="fonts/vermin_vibes.ttf" />

Note: you put the name of .ttf file you have. then go to to your css file and add:

h1 {
    color: blue;
    font-family: vermin vibes;
}

Note: you put the font family name of the font you have.

Note: do not write the font-family name as your font.ttf name example: if your font.ttf name is: "vermin_vibes.ttf" your font-family will be: "vermin vibes" font family doesn't contain special chars as "-,_"...etc it only can contain spaces.

How do I log errors and warnings into a file?

Simply put these codes at top of your PHP/index file:

error_reporting(E_ALL); // Error/Exception engine, always use E_ALL

ini_set('ignore_repeated_errors', TRUE); // always use TRUE

ini_set('display_errors', FALSE); // Error/Exception display, use FALSE only in production environment or real server. Use TRUE in development environment

ini_set('log_errors', TRUE); // Error/Exception file logging engine.
ini_set('error_log', 'your/path/to/errors.log'); // Logging file path

What is the difference between application server and web server?

Most of the times these terms Web Server and Application server are used interchangeably.

Following are some of the key differences in features of Web Server and Application Server:

  • Web Server is designed to serve HTTP Content. App Server can also serve HTTP Content but is not limited to just HTTP. It can be provided other protocol support such as RMI/RPC
  • Web Server is mostly designed to serve static content, though most Web Servers have plugins to support scripting languages like Perl, PHP, ASP, JSP etc. through which these servers can generate dynamic HTTP content.
  • Most of the application servers have Web Server as integral part of them, that means App Server can do whatever Web Server is capable of. Additionally App Server have components and features to support Application level services such as Connection Pooling, Object Pooling, Transaction Support, Messaging services etc.
  • As web servers are well suited for static content and app servers for dynamic content, most of the production environments have web server acting as reverse proxy to app server. That means while servicing a page request, static contents (such as images/Static HTML) are served by web server that interprets the request. Using some kind of filtering technique (mostly extension of requested resource) web server identifies dynamic content request and transparently forwards to app server

Example of such configuration is Apache Tomcat HTTP Server and Oracle (formerly BEA) WebLogic Server. Apache Tomcat HTTP Server is Web Server and Oracle WebLogic is Application Server.

In some cases the servers are tightly integrated such as IIS and .NET Runtime. IIS is web server. When equipped with .NET runtime environment, IIS is capable of providing application services.

Simple check for SELECT query empty result

SELECT COUNT(1) FROM service s WHERE s.service_id = ?

How to get changes from another branch

git fetch origin our-team

or

git pull origin our-team

but first you should make sure that you already on the branch you want to update to (featurex).

How to change value of ArrayList element in java

Use the set method to replace the old value with a new one.

list.set( 2, "New" );

Disable all gcc warnings

-w is the GCC-wide option to disable warning messages.

SCRIPT5: Access is denied in IE9 on xmlhttprequest

I had faced similar issue on IE10. I had a workaround by using the jQuery ajax request to retrieve data:

$.ajax({
    url: YOUR_XML_FILE
    aync: false,
    success: function (data) {   
        // Store data into a variable
    },
    dataType: YOUR_DATA_TYPE,
    complete: ON_COMPLETE_FUNCTION_CALL
});

array of string with unknown size

string foo = "Apple, Plum, Cherry";

string[] myArr = null;

myArr = foo.Split(',');

How to change heatmap.2 color range in R?

I think you need to set symbreaks = FALSE That should allow for asymmetrical color scales.

How do I know the script file name in a Bash script?

# ------------- SCRIPT ------------- #

#!/bin/bash

echo
echo "# arguments called with ---->  ${@}     "
echo "# \$1 ---------------------->  $1       "
echo "# \$2 ---------------------->  $2       "
echo "# path to me --------------->  ${0}     "
echo "# parent path -------------->  ${0%/*}  "
echo "# my name ------------------>  ${0##*/} "
echo
exit

# ------------- CALLED ------------- #

# Notice on the next line, the first argument is called within double, 
# and single quotes, since it contains two words

$  /misc/shell_scripts/check_root/show_parms.sh "'hello there'" "'william'"

# ------------- RESULTS ------------- #

# arguments called with --->  'hello there' 'william'
# $1 ---------------------->  'hello there'
# $2 ---------------------->  'william'
# path to me -------------->  /misc/shell_scripts/check_root/show_parms.sh
# parent path ------------->  /misc/shell_scripts/check_root
# my name ----------------->  show_parms.sh

# ------------- END ------------- #

How to create a hidden <img> in JavaScript?

You can hide an image using javascript like this:

document.images['imageName'].style.visibility = hidden;

If that isn't what you are after, you need to explain yourself more clearly.

How to check the maximum number of allowed connections to an Oracle database?

Note: this only answers part of the question.

If you just want to know the maximum number of sessions allowed, then you can execute in sqlplus, as sysdba:

SQL> show parameter sessions

This gives you an output like:

    NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
java_max_sessionspace_size           integer     0
java_soft_sessionspace_limit         integer     0
license_max_sessions                 integer     0
license_sessions_warning             integer     0
sessions                             integer     248
shared_server_sessions               integer

The sessions parameter is the one what you want.

How to add an image to the "drawable" folder in Android Studio?

Do it through the way Android Studio provided to you

Right click on the res folder and add your image as Image Assets in this way. Android studio will automatically generate image assets with different resolutions.

You can directly create the folder and drag image inside but you won't have the different sized icons if you do that.

enter image description here

How can I pass arguments to a batch file?

Here's how I did it:

@fake-command /u %1 /p %2

Here's what the command looks like:

test.cmd admin P@55w0rd > test-log.txt

The %1 applies to the first parameter the %2 (and here's the tricky part) applies to the second. You can have up to 9 parameters passed in this way.

403 Forbidden vs 401 Unauthorized HTTP responses

This question was asked some time ago, but people's thinking moves on.

Section 6.5.3 in this draft (authored by Fielding and Reschke) gives status code 403 a slightly different meaning to the one documented in RFC 2616.

It reflects what happens in authentication & authorization schemes employed by a number of popular web-servers and frameworks.

I've emphasized the bit I think is most salient.

6.5.3. 403 Forbidden

The 403 (Forbidden) status code indicates that the server understood the request but refuses to authorize it. A server that wishes to make public why the request has been forbidden can describe that reason in the response payload (if any).

If authentication credentials were provided in the request, the server considers them insufficient to grant access. The client SHOULD NOT repeat the request with the same credentials. The client MAY repeat the request with new or different credentials. However, a request might be forbidden for reasons unrelated to the credentials.

An origin server that wishes to "hide" the current existence of a forbidden target resource MAY instead respond with a status code of 404 (Not Found).

Whatever convention you use, the important thing is to provide uniformity across your site / API.

RGB to hex and hex to RGB

R = HexToR("#FFFFFF");
G = HexToG("#FFFFFF");
B = HexToB("#FFFFFF");

function HexToR(h) {return parseInt((cutHex(h)).substring(0,2),16)}
function HexToG(h) {return parseInt((cutHex(h)).substring(2,4),16)}
function HexToB(h) {return parseInt((cutHex(h)).substring(4,6),16)}
function cutHex(h) {return (h.charAt(0)=="#") ? h.substring(1,7):h}

Use these Function to achive the result without any issue. :)

Round button with text and icon in flutter

Congrats to the previous answers... But I realised if the icons are in a row (say three icons as represented in the image above), you need to play around with columns and rows.

Here is the code

 Column(
        crossAxisAlignment: CrossAxisAlignment.start,
            children: <Widget>[
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceAround,
                children: [
                  FlatButton(
                      onPressed: () {},
                      child: Icon(
                        Icons.call,
                      )),
                  FlatButton(
                      onPressed: () {},
                      child: Icon(
                        Icons.message,
                      )),
                  FlatButton(
                      onPressed: () {},
                      child: Icon(
                        Icons.block,
                        color: Colors.red,
                      )),
                ],
              ),
              Row(
                mainAxisAlignment: MainAxisAlignment.spaceAround,
                children: <Widget>[
                  Text(
                    '   Call',
                  ),
                  Text(
                    'Message',
                  ),
                  Text(
                    'Block',
                    style: TextStyle(letterSpacing: 2.0, color: Colors.red),
                  ),
                ],
              ),
            ],
          ),

Here is the result

WAMP Server ERROR "Forbidden You don't have permission to access /phpmyadmin/ on this server."

Go to C:\wamp\alias. Open the file phpmyadmin.conf and change

<Directory "c:/wamp/apps/phpmyadmin3.5.1/">
    Options Indexes FollowSymLinks MultiViews
    AllowOverride all
        Order Deny,Allow
    Deny from all
    Allow from 127.0.0.1
</Directory>

to

<Directory "c:/wamp/apps/phpmyadmin3.5.1/">
    Options Indexes FollowSymLinks MultiViews
    AllowOverride all
        Order Allow,Deny
    Allow from all
</Directory>

problem solved

Printing all global variables/local variables?

In case you want to see the local variables of a calling function use select-frame before info locals

E.g.:

(gdb) bt
#0  0xfec3c0b5 in _lwp_kill () from /lib/libc.so.1
#1  0xfec36f39 in thr_kill () from /lib/libc.so.1
#2  0xfebe3603 in raise () from /lib/libc.so.1
#3  0xfebc2961 in abort () from /lib/libc.so.1
#4  0xfebc2bef in _assert_c99 () from /lib/libc.so.1
#5  0x08053260 in main (argc=1, argv=0x8047958) at ber.c:480
(gdb) info locals
No symbol table info available.
(gdb) select-frame 5
(gdb) info locals
i = 28
(gdb) 

Splitting a dataframe string column into multiple different columns

The way via unlist and matrix seems a bit convoluted, and requires you to hard-code the number of elements (this is actually a pretty big no-go. Of course you could circumvent hard-coding that number and determine it at run-time)

I would go a different route, and construct a data frame directly from the list that strsplit returns. For me, this is conceptually simpler. There are essentially two ways of doing this:

  1. as.data.frame – but since the list is exactly the wrong way round (we have a list of rows rather than a list of columns) we have to transpose the result. We also clear the rownames since they are ugly by default (but that’s strictly unnecessary!):

    `rownames<-`(t(as.data.frame(strsplit(text, '\\.'))), NULL)
    
  2. Alternatively, use rbind to construct a data frame from the list of rows. We use do.call to call rbind with all the rows as separate arguments:

    do.call(rbind, strsplit(text, '\\.'))
    

Both ways yield the same result:

     [,1] [,2] [,3]  [,4]
[1,] "F"  "US" "CLE" "V13"
[2,] "F"  "US" "CA6" "U13"
[3,] "F"  "US" "CA6" "U13"
[4,] "F"  "US" "CA6" "U13"
[5,] "F"  "US" "CA6" "U13"
[6,] "F"  "US" "CA6" "U13"
…

Clearly, the second way is much simpler than the first.

Value of type 'T' cannot be converted to

If you're checking for explicit types, why are you declaring those variables as T's?

T HowToCast<T>(T t)
{
    if (typeof(T) == typeof(string))
    {
        var newT1 = "some text";
        var newT2 = t;  //this builds but I'm not sure what it does under the hood.
        var newT3 = t.ToString();  //for sure the string you want.
    }

    return t;
}

How to fix 'android.os.NetworkOnMainThreadException'?

android.os.NetworkOnMainThreadException is thrown when network operations are performed on the main thread. You better do this in AsyncTask to remove this Exception. Write it this way:

    new AsyncTask<Void,String,String>(){

        @Override
        protected Void doInBackground(Void... params) {
            // Perform your network operation.
            // Get JSON or XML string from the server.
            // Store in a local variable (say response) and return.
            return response;
        }

        protected void onPostExecute(String results){
            // Response returned by doInBackGround() will be received
            // by onPostExecute(String results).
            // Now manipulate your jason/xml String(results).
        }

    }.execute();
}

SqlBulkCopy - The given value of type String from the data source cannot be converted to type money of the specified target column

Not going to be everyone's fix, but it was for me:

So, i ran across this exact issue. The problem I seemed to have was when my DataTable didnt have an ID column, but the target destination had one with a primary key.

When i adapted my DataTable to have an id, the copy worked perfectly.

In my scenario, the Id column isnt very important to have the primary key so i deleted this column from the target destination table and the SqlBulkCopy is working without issue.

Android SDK installation doesn't find JDK

Actual SETUP:

  • OS: Windows 8.1
  • JDK file: jdk-8u11-windows-x64.exe
  • ADT file: installer_r23.0.2-windows.exe

Install the x64 JDK, and try the back-next option first, and then try setting JAVA_HOME like the error message says, but if that doesn't work for you either, then try this:

Do as it says, set JAVA_HOME in your environment variables, but in the path use forward slashes instead of backslashes.

Seriously.

For me it failed when JAVA_HOME was C:\Program Files\Java\jdk1.6.0_31 but worked fine when it was C:/Program Files/Java/jdk1.6.0_31 - drove me nuts!

If this is not enough, also add to the beginning of the Environment Variable Path %JAVA_HOME%;

Updated values in System Environment Variables:

  • JAVA_HOME=C:/Program Files/Java/jdk1.8.0_11
  • JRE_HOME=C:/Program Files/Java/jre8
  • Path=%JAVA_HOME%;C:...

How to convert index of a pandas dataframe into a column?

either:

df['index1'] = df.index

or, .reset_index:

df.reset_index(level=0, inplace=True)

so, if you have a multi-index frame with 3 levels of index, like:

>>> df
                       val
tick       tag obs        
2016-02-26 C   2    0.0139
2016-02-27 A   2    0.5577
2016-02-28 C   6    0.0303

and you want to convert the 1st (tick) and 3rd (obs) levels in the index into columns, you would do:

>>> df.reset_index(level=['tick', 'obs'])
          tick  obs     val
tag                        
C   2016-02-26    2  0.0139
A   2016-02-27    2  0.5577
C   2016-02-28    6  0.0303

Pandas: Setting no. of max rows

As in this answer to a similar question, there is no need to hack settings. It is much simpler to write:

print(foo.to_string())

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

This error comes when you are trying to load jasper report file with the extension .jasper
For Example 
c://reports//EmployeeReport.jasper"

While you should load jasper report file with the extension .jrxml
For Example 
c://reports//EmployeeReport.jrxml"
[See Problem Screenshot ][1] [1]: https://i.stack.imgur.com/D5SzR.png
[See Solution Screenshot][2] [2]: https://i.stack.imgur.com/VeQb9.png

  
  

Is Django for the frontend or backend?

It seems you're actually talking about an MVC (Model-View-Controller) pattern, where logic is separated into various "tiers". Django, as a framework, follows MVC (loosely). You have models that contain your business logic and relate directly to tables in your database, views which in effect act like the controller, handling requests and returning responses, and finally, templates which handle presentation.

Django isn't just one of these, it is a complete framework for application development and provides all the tools you need for that purpose.

Frontend vs Backend is all semantics. You could potentially build a Django app that is entirely "backend", using its built-in admin contrib package to manage the data for an entirely separate application. Or, you could use it solely for "frontend", just using its views and templates but using something else entirely to manage the data. Most usually, it's used for both. The built-in admin (the "backend"), provides an easy way to manage your data and you build apps within Django to present that data in various ways. However, if you were so inclined, you could also create your own "backend" in Django. You're not forced to use the default admin.

INSTALL_FAILED_DUPLICATE_PERMISSION... C2D_MESSAGE

None of the above worked for me. My app was working fine in previous than Lollipop. But when I tested it on Lollipop the above error came up. It refused to install. I didn't have any previous versions installed so all the above solutions are invalid in my case. But thanks to this SO solution now it is running fine. Just like most developers I followed Google's misleading tutorial and I added the permissions by copy and paste like this:

<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
<permission android:name="com.google.android.permission.C2D_MESSAGE" 
            android:protectionLevel="signature" />

This would work with older versions < Lollipop. So now I changed to:

<uses-permission android:name="com.mycompany.myappname.c2dm.permission.RECEIVE" />
<permission android:name="com.mycompany.myappname.permission.C2D_MESSAGE" 
            android:protectionLevel="signature" />

How to get current time in python and break up into year, month, day, hour, minute?

This is an older question, but I came up with a solution I thought others might like.

def get_current_datetime_as_dict():
n = datetime.now()
t = n.timetuple()
field_names = ["year",
               "month",
               "day",
               "hour",
               "min",
               "sec",
               "weekday",
               "md",
               "yd"]
return dict(zip(field_names, t))

timetuple() can be zipped with another array, which creates labeled tuples. Cast that to a dictionary and the resultant product can be consumed with get_current_datetime_as_dict()['year'].

This has a little more overhead than some of the other solutions on here, but I've found it's so nice to be able to access named values for clartiy's sake in the code.

Turn off iPhone/Safari input element rounding

The accepted answer made radio button disappear on Chrome. This works:

input:not([type="radio"]):not([type="checkbox"]) {
    -webkit-appearance: none;
    border-radius: 0;
}

Unable to ping vmware guest from another vmware guest

I would like to add, that yes. While using the NAT adapter settings in Vmware and turning off windows firewall I was able to ping other guest machines in my test environment.

Sidenote: Best practice would be to implement a hardware firewall in larger environments and turn off windows firewall on the Domain Controller.

How to create a global variable?

if you want to use it in all of your classes you can use:

public var yourVariable = "something"

if you want to use just in one class you can use :

var yourVariable = "something"

List append() in for loop

The list.append function does not return any value(but None), it just adds the value to the list you are using to call that method.

In the first loop round you will assign None (because the no-return of append) to a, then in the second round it will try to call a.append, as a is None it will raise the Exception you are seeing

You just need to change it to:

a=[]
for i in range(5):    
    a.append(i)
print(a)
# [0, 1, 2, 3, 4]

list.append is what is called a mutating or destructive method, i.e. it will destroy or mutate the previous object into a new one(or a new state).

If you would like to create a new list based in one list without destroying or mutating it you can do something like this:

a=['a', 'b', 'c']
result = a + ['d']

print result
# ['a', 'b', 'c', 'd']

print a
# ['a', 'b', 'c']

As a corollary only, you can mimic the append method by doing the following:

a=['a', 'b', 'c']
a = a + ['d']

print a
# ['a', 'b', 'c', 'd']

java.security.AccessControlException: Access denied (java.io.FilePermission

Although it is not recommended, but if you really want to let your web application access a folder outside its deployment directory. You need to add following permission in java.policy file (path is as in the reply of Petey B)

permission java.io.FilePermission "your folder path", "write"

In your case it would be

permission java.io.FilePermission "S:/PDSPopulatingProgram/-", "write"

Here /- means any files or sub-folders inside this folder.

Warning: But by doing this, you are inviting some security risk.

Find the 2nd largest element in an array with minimum number of comparisons

Suppose provided array is inPutArray = [1,2,5,8,7,3] expected O/P -> 7 (second largest)

 take temp array 
      temp = [0,0], int dummmy=0;
    for (no in inPutArray) {
    if(temp[1]<no)
     temp[1] = no
     if(temp[0]<temp[1]){
    dummmy = temp[0]
    temp[0] = temp[1]
    temp[1] = temp
      }
    }

    print("Second largest no is %d",temp[1])

Printing chars and their ASCII-code in C

To print all the ascii values from 0 to 255 using while loop.

#include<stdio.h>

int main(void)
{
    int a;
    a = 0;
    while (a <= 255)
    {
        printf("%d = %c\n", a, a);
        a++;
    }
    return 0;
}

How can I compare strings in C using a `switch` statement?

There is no way to do this in C. There are a lot of different approaches. Typically the simplest is to define a set of constants that represent your strings and do a look up by string on to get the constant:

#define BADKEY -1
#define A1 1
#define A2 2
#define B1 3
#define B2 4

typedef struct { char *key; int val; } t_symstruct;

static t_symstruct lookuptable[] = {
    { "A1", A1 }, { "A2", A2 }, { "B1", B1 }, { "B2", B2 }
};

#define NKEYS (sizeof(lookuptable)/sizeof(t_symstruct))

int keyfromstring(char *key)
{
    int i;
    for (i=0; i < NKEYS; i++) {
        t_symstruct *sym = lookuptable[i];
        if (strcmp(sym->key, key) == 0)
            return sym->val;
    }
    return BADKEY;
}

/* ... */
switch (keyfromstring(somestring)) {
case A1: /* ... */ break;
case A2: /* ... */ break;
case B1: /* ... */ break;
case B2: /* ... */ break;
case BADKEY: /* handle failed lookup */
}

There are, of course, more efficient ways to do this. If you keep your keys sorted, you can use a binary search. You could use a hashtable too. These things change your performance at the expense of maintenance.

Using PHP Replace SPACES in URLS with %20

You've got several options how to do this, either:

strtr()

Assuming that you want to replace "\t" and " " with "%20":

$replace_pairs = array(
  "\t" => '%20',
  " " => '%20',
);
return strtr( $text, $replace_pairs)

preg_replace()

You've got few options here, either replacing just space ~ ~, again replacing space and tab ~[ \t]~ or all kinds of spaces ~\s~:

return preg_replace( '~\s~', '%20', $text);

Or when you need to replace string like this "\t \t \t \t" with just one %20:

return preg_replace( '~\s+~', '%20', $text);

I assumed that you really want to use manual string replacement and handle more types of whitespaces such as non breakable space (&nbsp;)

Spaces cause split in path with PowerShell

For any file path with space, simply put them in double quotations will work in Windows Powershell. For example, if you want to go to Program Files directory, instead of use

PS C:\> cd Program Files

which will induce error, simply use the following will solve the problem:

PS C:\> cd "Program Files"

Show div #id on click with jQuery

The problem you're having is that the event-handlers are being bound before the elements are present in the DOM, if you wrap the jQuery inside of a $(document).ready() then it should work perfectly well:

$(document).ready(
    function(){
        $("#music").click(function () {
            $("#musicinfo").show("slow");
        });

    });

An alternative is to place the <script></script> at the foot of the page, so it's encountered after the DOM has been loaded and ready.

To make the div hide again, once the #music element is clicked, simply use toggle():

$(document).ready(
    function(){
        $("#music").click(function () {
            $("#musicinfo").toggle();
        });
    });

JS Fiddle demo.

And for fading:

$(document).ready(
    function(){
        $("#music").click(function () {
            $("#musicinfo").fadeToggle();
        });
    });

JS Fiddle demo.

HRESULT: 0x800A03EC on Worksheet.range

I don't understand the issue. But here is the thing that solved my issue.

Go to Excel Options > Save > Save Files in this format > Select "Excel Workbook(*.xlsx)". Previously, my WorkBooks were opening in [Compatibuility Mode] And now they are opening in normal mode. Range function works fine with that.

Keep CMD open after BAT file executes

start cmd /k did the magic for me. I actually used it for preparing cordova phonegap app it runs the command, shows the result and waits for the user to close it. Below is the simple example

start cmd /k echo Hello, World!

What I did use in my case

start cmd /k cordova prepare

Update

You could even have a title for this by using

start "My Title" echo Hello, World!

What does %s mean in a python format string?

Andrew's answer is good.

And just to help you out a bit more, here's how you use multiple formatting in one string

"Hello %s, my name is %s" % ('john', 'mike') # Hello john, my name is mike".

If you are using ints instead of string, use %d instead of %s.

"My name is %s and i'm %d" % ('john', 12) #My name is john and i'm 12

Numpy where function multiple conditions

I have worked out this simple example

import numpy as np

ar = np.array([3,4,5,14,2,4,3,7])

print [X for X in list(ar) if (X >= 3 and X <= 6)]

>>> 
[3, 4, 5, 4, 3]

jQuery UI Dialog Box - does not open after being closed

on the last line, don't use $(this).remove() use $(this).hide() instead.

EDIT: To clarify,on the close click event you're removing the #terms div from the DOM which is why its not coming back. You just need to hide it instead.

Java SimpleDateFormat for time zone with a colon separator?

Try setLenient(false).

Addendum: It looks like you're recognizing variously formatted Date strings. If you have to do entry, you might like looking at this example that extends InputVerifier.

How to disable submit button once it has been clicked?

I think easy way to disable button is :data => { disable_with: "Saving.." } This will submit a form and then make a button disable, Also it won't disable button if you have any validations like required = 'required'.

Why does CSV file contain a blank line in between each data line when outputting with Dictwriter in Python

By default, the classes in the csv module use Windows-style line terminators (\r\n) rather than Unix-style (\n). Could this be what’s causing the apparent double line breaks?

If so, you can override it in the DictWriter constructor:

output = csv.DictWriter(open('file3.csv','w'), delimiter=',', lineterminator='\n', fieldnames=headers)

How to prevent line breaks in list items using CSS

Bootstrap 4 has a class named text-nowrap. It is just what you need.

Find the unique values in a column and then sort them

Another way is using set data type.

Some characteristic of Sets: Sets are unordered, can include mixed data types, elements in a set cannot be repeated, are mutable.

Solving your question:

df = pd.DataFrame({'A':[1,1,3,2,6,2,8]})
sorted(set(df.A))

The answer in List type:

[1, 2, 3, 6, 8]

How to check if C string is empty

With strtok(), it can be done in just one line: "if (strtok(s," \t")==NULL)". For example:

#include <stdio.h>
#include <string.h>

int is_whitespace(char *s) {
    if (strtok(s," \t")==NULL) {
        return 1;
    } else {
        return 0;
    }
}

void demo(void) {
    char s1[128];
    char s2[128];
    strcpy(s1,"   abc  \t ");
    strcpy(s2,"    \t   ");
    printf("s1 = \"%s\"\n", s1);
    printf("s2 = \"%s\"\n", s2);
    printf("is_whitespace(s1)=%d\n",is_whitespace(s1));
    printf("is_whitespace(s2)=%d\n",is_whitespace(s2));
}

int main() {
    char url[63] = {'\0'};
    do {
        printf("Enter a URL: ");
        scanf("%s", url);
        printf("url='%s'\n", url);
    } while (is_whitespace(url));
    return 0;
}

A JSONObject text must begin with '{' at 1 [character 2 line 1] with '{' error

The file that I was using was saved through Powershell in UTF-8 format. I changed it to ANSI and it fixed the problem.

What is difference between INNER join and OUTER join

INNER JOIN: Returns all rows when there is at least one match in BOTH tables

LEFT JOIN: Return all rows from the left table, and the matched rows from the right table

RIGHT JOIN: Return all rows from the right table, and the matched rows from the left table

FULL JOIN: Return all rows when there is a match in ONE of the tables

Spring + Web MVC: dispatcher-servlet.xml vs. applicationContext.xml (plus shared security)

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:cache="http://www.springframework.org/schema/cache"
    xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd  http://www.springframework.org/schema/cache 
        http://www.springframework.org/schema/cache/spring-cache-3.2.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

        <mvc:annotation-driven/>
        <context:component-scan base-package="com.testpoc.controller"/>

        <bean id="ViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="ViewClass" value="org.springframework.web.servlet.view.JstlView"></property>
            <property name="prefix">
                <value>/WEB-INF/pages/</value>
            </property>
            <property name="suffix">
                <value>.jsp</value>
            </property>
        </bean>

</beans>

What's the difference between django OneToOneField and ForeignKey?

OneToOneField (one-to-one) realizes, in object orientation, the notion of composition, while ForeignKey (one-to-many) relates to agregation.

How to uninstall Apache with command line

On Windows 8.1 I had to run cmd.exe as administrator (even though I was logged in as admin). Otherwise I got an error when trying to execute: httpd.exe -k uninstall

Error: C:\Program Files\Apache\bin>(OS 5)Access is denied. : AH00373: Apache2.4: OpenS ervice failed

How to read specific lines from a file (by line number)?

I prefer this approach because it's more general-purpose, i.e. you can use it on a file, on the result of f.readlines(), on a StringIO object, whatever:

def read_specific_lines(file, lines_to_read):
   """file is any iterable; lines_to_read is an iterable containing int values"""
   lines = set(lines_to_read)
   last = max(lines)
   for n, line in enumerate(file):
      if n + 1 in lines:
          yield line
      if n + 1 > last:
          return

>>> with open(r'c:\temp\words.txt') as f:
        [s for s in read_specific_lines(f, [1, 2, 3, 1000])]
['A\n', 'a\n', 'aa\n', 'accordant\n']

Retrieving parameters from a URL

for Python > 3.4

from urllib import parse
url = 'http://foo.appspot.com/abc?def=ghi'
query_def=parse.parse_qs(parse.urlparse(url).query)['def'][0]

Remove a modified file from pull request

You would want to amend the commit and then do a force push which will update the branch with the PR.

Here's how I recommend you do this:

  1. Close the PR so that whomever is reviewing it doesn't pull it in until you've made your changes.
  2. Do a Soft reset to the commit before your unwanted change (if this is the last commit you can use git reset --soft HEAD^ or if it's a different commit, you would want to replace 'HEAD^' with the commit id)
  3. Discard (or undo) any changes to the file that you didn't intend to update
  4. Make a new commit git commit -a -c ORIG_HEAD
  5. Force Push to your branch
  6. Re-Open Pull Request

The now that your branch has been updated, the Pull Request will include your changes.

Here's a link to Gits documentation where they have a pretty good example under Undo a commit and redo.

Load image with jQuery and append it to the DOM

Here is the code I use when I want to preload images before appending them to the page.

It is also important to check if the image is already loaded from the cache (for IE).

    //create image to preload:
    var imgPreload = new Image();
    $(imgPreload).attr({
        src: photoUrl
    });

    //check if the image is already loaded (cached):
    if (imgPreload.complete || imgPreload.readyState === 4) {

        //image loaded:
        //your code here to insert image into page

    } else {
        //go fetch the image:
        $(imgPreload).load(function (response, status, xhr) {
            if (status == 'error') {

                //image could not be loaded:

            } else {

                //image loaded:
                //your code here to insert image into page

            }
        });
    }

Comma separated results in SQL

Use FOR XML PATH('') - which is converting the entries to a comma separated string and STUFF() -which is to trim the first comma- as follows Which gives you the same comma separated result

SELECT  STUFF((SELECT  ',' + INSTITUTIONNAME
            FROM EDUCATION EE
            WHERE  EE.STUDENTNUMBER=E.STUDENTNUMBER
            ORDER BY sortOrder
        FOR XML PATH('')), 1, 1, '') AS listStr

FROM EDUCATION E
GROUP BY E.STUDENTNUMBER

Here is the FIDDLE

PreparedStatement with list of parameters in a IN clause

Using Java 8 APIs, 

    List<Long> empNoList = Arrays.asList(1234, 7678, 2432, 9756556, 3354646);

    List<String> parameters = new ArrayList<>();
    empNoList.forEach(empNo -> parameters.add("?"));   //Use forEach to add required no. of '?'
    String commaSepParameters = String.join(",", parameters); //Use String to join '?' with ','

StringBuilder selectQuery = new StringBuilder().append("SELECT COUNT(EMP_ID) FROM EMPLOYEE WHERE EMP_ID IN (").append(commaSepParameters).append(")");

How to call a .NET Webservice from Android using KSOAP2?

You can Use below code to call the web service and get response .Make sure that your Web Service return the response in Data Table Format..This code help you if you using data from SQL Server database .If you you using MYSQL you need to change one thing just replace word NewDataSet from sentence obj2=(SoapObject) obj1.getProperty("NewDataSet"); by DocumentElement

private static final String NAMESPACE = "http://tempuri.org/";
private static final String URL = "http://localhost/Web_Service.asmx?"; // you can use   IP address instead of localhost
private static final String METHOD_NAME = "Function_Name";
private static final String SOAP_ACTION = NAMESPACE + METHOD_NAME;

SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
request.addProperty("parm_name", prm_value); // Parameter for Method
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
envelope.dotNet = true;
envelope.setOutputSoapObject(request);
HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);

try {
    androidHttpTransport.call(SOAP_ACTION, envelope); //call the eb service Method
} catch (Exception e) {
    e.printStackTrace();
} //Next task is to get Response and format that response

SoapObject obj, obj1, obj2, obj3;
obj = (SoapObject) envelope.getResponse();
obj1 = (SoapObject) obj.getProperty("diffgram");
obj2 = (SoapObject) obj1.getProperty("NewDataSet");

for (int i = 0; i < obj2.getPropertyCount(); i++) //the method getPropertyCount() return the number of rows
{
    obj3 = (SoapObject) obj2.getProperty(i);
    obj3.getProperty(0).toString(); //value of column 1
    obj3.getProperty(1).toString(); //value of column 2
    //like that you will get value from each column
}

If you have any problem regarding this you can write me..

Add Keypair to existing EC2 instance

This happened to me earlier (didn't have access to an EC2 instance someone else created but had access to AWS web console) and I blogged the answer: http://readystate4.com/2013/04/09/aws-gaining-ssh-access-to-an-ec2-instance-you-lost-access-to/

Basically, you can detached the EBS drive, attach it to an EC2 that you do have access to. Add your SSH pub key to ~ec2-user/.ssh/authorized_keys on this attached drive. Then put it back on the old EC2 instance. step-by-step in the link using Amazon AMI.

No need to make snapshots or create a new cloned instance.

Instagram API - How can I retrieve the list of people a user is following on Instagram

Here's a way to get the list of people a user is following with just a browser and some copy-paste (A pure javascript solution based on Deep Seeker's answer):

  1. Get the user's id (In a browser, navigate to https://www.instagram.com/user_name/?__a=1 and look for response -> graphql -> user -> id [from Deep Seeker's answer])

  2. Open another browser window

  3. Open the browser console and paste this in it

    _x000D_
    _x000D_
    options = {
        userId: your_user_id,
        list: 1 //1 for following, 2 for followers
    }
    _x000D_
    _x000D_
    _x000D_

  4. change to your user id and hit enter

  5. paste this in the console and hit enter

    _x000D_
    _x000D_
    `https://www.instagram.com/graphql/query/?query_hash=c76146de99bb02f6415203be841dd25a&variables=` + encodeURIComponent(JSON.stringify({
            "id": options.userId,
            "include_reel": true,
            "fetch_mutual": true,
            "first": 50
        }))
    _x000D_
    _x000D_
    _x000D_

  6. Navigate to the outputted link

(This sets up the headers for the http request. If you try to run the script on a page where this isn't open, it won't work.)

  1. In the console for the page you just opened, paste this and hit enter
    _x000D_
    _x000D_
    let config = {
      followers: {
        hash: 'c76146de99bb02f6415203be841dd25a',
        path: 'edge_followed_by'
      },
      following: {
        hash: 'd04b0a864b4b54837c0d870b0e77e076',
        path: 'edge_follow'
      }
    };
    
    var allUsers = [];
    
    function getUsernames(data) {
        var userBatch = data.map(element => element.node.username);
        allUsers.push(...userBatch);
    }
    
    async function makeNextRequest(nextCurser, listConfig) {
        var params = {
            "id": options.userId,
            "include_reel": true,
            "fetch_mutual": true,
            "first": 50
        };
        if (nextCurser) {
            params.after = nextCurser;
        }
        var requestUrl = `https://www.instagram.com/graphql/query/?query_hash=` + listConfig.hash + `&variables=` + encodeURIComponent(JSON.stringify(params));
    
        var xhr = new XMLHttpRequest();
        xhr.onload = function(e) {
            var res = JSON.parse(xhr.response);
    
            var userData = res.data.user[listConfig.path].edges;
            getUsernames(userData);
    
            var curser = "";
            try {
                curser = res.data.user[listConfig.path].page_info.end_cursor;
            } catch {
    
            }
            var users = [];
            if (curser) {
                makeNextRequest(curser, listConfig);
            } else {
                var printString =""
                allUsers.forEach(item => printString = printString + item + "\n");
                console.log(printString);
            }
        }
    
        xhr.open("GET", requestUrl);
        xhr.send();
    }
    
    if (options.list === 1) {
    
        console.log('following');
        makeNextRequest("", config.following);
    } else if (options.list === 2) {
    
        console.log('followers');
        makeNextRequest("", config.followers);
    }
    _x000D_
    _x000D_
    _x000D_

After a few seconds it should output the list of users your user is following.

How can I count all the lines of code in a directory recursively?

None of the answers so far gets at the problem of filenames with spaces.

Additionally, all that use xargs are subject to fail if the total length of paths in the tree exceeds the shell environment size limit (defaults to a few megabytes in Linux).

Here is one that fixes these problems in a pretty direct manner. The subshell takes care of files with spaces. The awk totals the stream of individual file wc outputs, so it ought never to run out of space. It also restricts the exec to files only (skipping directories):

find . -type f -name '*.php' -exec bash -c 'wc -l "$0"' {} \; | awk '{s+=$1} END {print s}'

How to create a fix size list in python?

This is more of a warning than an answer.
Having seen in the other answers my_list = [None] * 10, I was tempted and set up an array like this speakers = [['','']] * 10 and came to regret it immensely as the resulting list did not behave as I thought it should.
I resorted to:

speakers = []
for i in range(10):
    speakers.append(['',''])

As [['','']] * 10 appears to create an list where subsequent elements are a copy of the first element.
for example:

>>> n=[['','']]*10
>>> n
[['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', '']]
>>> n[0][0] = "abc"
>>> n
[['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', ''], ['abc', '']]
>>> n[0][1] = "True"
>>> n
[['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True'], ['abc', 'True']]

Whereas with the .append option:

>>> n=[]
>>> for i in range(10):
...  n.append(['',''])
... 
>>> n
[['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', '']]
>>> n[0][0] = "abc"
>>> n
[['abc', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', '']]
>>> n[0][1] = "True"
>>> n
[['abc', 'True'], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', ''], ['', '']]

I'm sure that the accepted answer by ninjagecko does attempt to mention this, sadly I was too thick to understand.
Wrapping up, take care!

jQuery’s .bind() vs. .on()

From the jQuery documentation:

As of jQuery 1.7, the .on() method is the preferred method for attaching event handlers to a document. For earlier versions, the .bind() method is used for attaching an event handler directly to elements. Handlers are attached to the currently selected elements in the jQuery object, so those elements must exist at the point the call to .bind() occurs. For more flexible event binding, see the discussion of event delegation in .on() or .delegate().

http://api.jquery.com/bind/

How to check if a file is a valid image file?

Additionally to the PIL image check you can also add file name extension check like this:

filename.lower().endswith(('.png', '.jpg', '.jpeg', '.tiff', '.bmp', '.gif'))

Note that this only checks if the file name has a valid image extension, it does not actually open the image to see if it's a valid image, that's why you need to use additionally PIL or one of the libraries suggested in the other answers.

Saving numpy array to txt file row wise

just

' '.join(a)

and write this output to a file.

phpexcel to download

$excel = new PHPExcel();
header('Content-Type: application/vnd.ms-excel');
header('Content-Disposition: attachment;filename="your_name.xls"');
header('Cache-Control: max-age=0');

// Do your stuff here

$writer = PHPExcel_IOFactory::createWriter($excel, 'Excel5');

// This line will force the file to download
$writer->save('php://output');

Left Outer Join using + sign in Oracle 11g

I saw some contradictions in the answers above, I just tried the following on Oracle 12c and the following is correct :

LEFT OUTER JOIN

SELECT *
FROM A, B
WHERE A.column = B.column(+)

RIGHT OUTER JOIN

SELECT *
FROM A, B
WHERE B.column(+) = A.column

MATLAB error: Undefined function or method X for input arguments of type 'double'

Also, name it divrat.m, not divrat.M. This shouldn't matter on most OSes, but who knows...

You can also test whether matlab can find a function by using the which command, i.e.

which divrat

Is there a way to make a PowerShell script work by double clicking a .ps1 file?

I wrote this a few years ago (run it with administrator rights):

<#
.SYNOPSIS
    Change the registry key in order that double-clicking on a file with .PS1 extension
    start its execution with PowerShell.
.DESCRIPTION
    This operation bring (partly) .PS1 files to the level of .VBS as far as execution
    through Explorer.exe is concern.
    This operation is not advised by Microsoft.
.NOTES
    File Name   : ModifyExplorer.ps1
    Author      : J.P. Blanc - [email protected]
    Prerequisite: PowerShell V2 on Vista and later versions.
    Copyright 2010 - Jean Paul Blanc/Silogix
.LINK
    Script posted on:
    http://www.silogix.fr
.EXAMPLE
    PS C:\silogix> Set-PowAsDefault -On
    Call Powershell for .PS1 files.
    Done!
.EXAMPLE
    PS C:\silogix> Set-PowAsDefault
    Tries to go back
    Done!
#>
function Set-PowAsDefault
{
  [CmdletBinding()]
  Param
  (
    [Parameter(mandatory=$false, ValueFromPipeline=$false)]
    [Alias("Active")]
    [switch]
    [bool]$On
  )

  begin
  {
    if ($On.IsPresent)
    {
      Write-Host "Call PowerShell for .PS1 files."
    }
    else
    {
      Write-Host "Try to go back."
    }
  }

  Process
  {
    # Text Menu
    [string]$TexteMenu = "Go inside PowerShell"

    # Text of the program to create
    [string] $TexteCommande = "%systemroot%\system32\WindowsPowerShell\v1.0\powershell.exe -Command ""&'%1'"""

    # Key to create
    [String] $clefAModifier = "HKLM:\SOFTWARE\Classes\Microsoft.PowerShellScript.1\Shell\Open\Command"

    try
    {
      $oldCmdKey = $null
      $oldCmdKey = Get-Item $clefAModifier -ErrorAction SilentlyContinue
      $oldCmdValue = $oldCmdKey.getvalue("")

      if ($oldCmdValue -ne $null)
      {
        if ($On.IsPresent)
        {
          $slxOldValue = $null
          $slxOldValue = Get-ItemProperty $clefAModifier -Name "slxOldValue" -ErrorAction SilentlyContinue
          if ($slxOldValue -eq $null)
          {
            New-ItemProperty $clefAModifier -Name "slxOldValue" -Value $oldCmdValue  -PropertyType "String" | Out-Null
            New-ItemProperty $clefAModifier -Name "(default)" -Value $TexteCommande  -PropertyType "ExpandString" | Out-Null
            Write-Host "Done !"
          }
          else
          {
            Write-Host "Already done!"
          }
        }
        else
        {
          $slxOldValue = $null
          $slxOldValue = Get-ItemProperty $clefAModifier -Name "slxOldValue" -ErrorAction SilentlyContinue
          if ($slxOldValue -ne $null)
          {
            New-ItemProperty $clefAModifier -Name "(default)" -Value $slxOldValue."slxOldValue"  -PropertyType "String" | Out-Null
            Remove-ItemProperty $clefAModifier -Name "slxOldValue"
            Write-Host "Done!"
          }
          else
          {
            Write-Host "No former value!"
          }
        }
      }
    }
    catch
    {
      $_.exception.message
    }
  }
  end {}
}

Get the last day of the month in SQL

Works in SQL server

Declare @GivenDate datetime
SET @GivenDate = GETDATE()

Select DATEADD(MM,DATEDIFF(MM, 0, @GivenDate),0) --First day of the month 

Select DATEADD(MM,DATEDIFF(MM, -1, @GivenDate),-1) --Last day of the month

Tri-state Check box in HTML?

You could use HTML's indeterminate IDL attribute on input elements.

removing new line character from incoming stream using sed

This might work for you:

printf "{new\nto\nlinux}" | paste -sd' '            
{new to linux}

or:

printf "{new\nto\nlinux}" | tr '\n' ' '            
{new to linux}

or:

printf "{new\nto\nlinux}" |sed -e ':a' -e '$!{' -e 'N' -e 'ba' -e '}' -e 's/\n/ /g'
{new to linux}

Remove Server Response Header IIS7

If you just want to remove the header you can use a shortened version of lukiffer's answer:

using System.Web;

namespace Site
{
    public sealed class HideServerHeaderModule : IHttpModule
    {
        public void Dispose() { }

        public void Init(HttpApplication context)
        {
            context.PreSendRequestHeaders +=
            (sender, e) => HttpContext.Current.Response.Headers.Remove("Server");
        }
    }
}

And then in Web.config:

<system.webServer>
  <modules runAllManagedModulesForAllRequests="true">
    <add name="CustomHeaderModule" type="Site.HideServerHeaderModule" />
  </modules>
</system.webServer>

How to completely uninstall python 2.7.13 on Ubuntu 16.04

Sometimes you need to first update the apt repo list.

sudo apt-get update
sudo apt purge python2.7-minimal

SQL: Group by minimum value in one field while selecting distinct rows

I could get to your expected result just by doing this in :

 SELECT id, min(record_date), other_cols 
  FROM mytable
  GROUP BY id

Does this work for you?

How to define the css :hover state in a jQuery selector?

It's too late, however the best example, how to add pseudo element in jQuery style

_x000D_
_x000D_
 $(document).ready(function(){_x000D_
 $("a.dummy").css({"background":"#003d79","color":"#fff","padding": "5px 10px","border-radius": "3px","text-decoration":"none"});_x000D_
 $("a.dummy").hover(function() {_x000D_
            $(this).css("background-color","#0670c9")_x000D_
          }).mouseout(function(){_x000D_
              $(this).css({"background-color":"#003d79",});_x000D_
          });_x000D_
 _x000D_
 });
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.1/jquery.min.js"></script>_x000D_
<a class="dummy" href="javascript:void()">Just Link</a>
_x000D_
_x000D_
_x000D_

Count the number occurrences of a character in a string

str = "count a character occurance"

List = list(str)
print (List)
Uniq = set(List)
print (Uniq)

for key in Uniq:
    print (key, str.count(key))

How to compare 2 dataTables

The OP, MAW74656, originally posted this answer in the question body in response to the accepted answer, as explained in this comment:

I used this and wrote a public method to call the code and return the boolean.

The OP's answer:

Code Used:

public bool tablesAreTheSame(DataTable table1, DataTable table2)
{
    DataTable dt;
    dt = getDifferentRecords(table1, table2);

    if (dt.Rows.Count == 0)
        return true;
    else
        return false;
}

//Found at http://canlu.blogspot.com/2009/05/how-to-compare-two-datatables-in-adonet.html
private DataTable getDifferentRecords(DataTable FirstDataTable, DataTable SecondDataTable)
{
    //Create Empty Table     
    DataTable ResultDataTable = new DataTable("ResultDataTable");

    //use a Dataset to make use of a DataRelation object     
    using (DataSet ds = new DataSet())
    {
        //Add tables     
        ds.Tables.AddRange(new DataTable[] { FirstDataTable.Copy(), SecondDataTable.Copy() });

        //Get Columns for DataRelation     
        DataColumn[] firstColumns = new DataColumn[ds.Tables[0].Columns.Count];
        for (int i = 0; i < firstColumns.Length; i++)
        {
            firstColumns[i] = ds.Tables[0].Columns[i];
        }

        DataColumn[] secondColumns = new DataColumn[ds.Tables[1].Columns.Count];
        for (int i = 0; i < secondColumns.Length; i++)
        {
            secondColumns[i] = ds.Tables[1].Columns[i];
        }

        //Create DataRelation     
        DataRelation r1 = new DataRelation(string.Empty, firstColumns, secondColumns, false);
        ds.Relations.Add(r1);

        DataRelation r2 = new DataRelation(string.Empty, secondColumns, firstColumns, false);
        ds.Relations.Add(r2);

        //Create columns for return table     
        for (int i = 0; i < FirstDataTable.Columns.Count; i++)
        {
            ResultDataTable.Columns.Add(FirstDataTable.Columns[i].ColumnName, FirstDataTable.Columns[i].DataType);
        }

        //If FirstDataTable Row not in SecondDataTable, Add to ResultDataTable.     
        ResultDataTable.BeginLoadData();
        foreach (DataRow parentrow in ds.Tables[0].Rows)
        {
            DataRow[] childrows = parentrow.GetChildRows(r1);
            if (childrows == null || childrows.Length == 0)
                ResultDataTable.LoadDataRow(parentrow.ItemArray, true);
        }

        //If SecondDataTable Row not in FirstDataTable, Add to ResultDataTable.     
        foreach (DataRow parentrow in ds.Tables[1].Rows)
        {
            DataRow[] childrows = parentrow.GetChildRows(r2);
            if (childrows == null || childrows.Length == 0)
                ResultDataTable.LoadDataRow(parentrow.ItemArray, true);
        }
        ResultDataTable.EndLoadData();
    }

    return ResultDataTable;
}

How to write new line character to a file in Java

The BufferedWriter class offers a newLine() method. Using this will ensure platform independence.

How to filter array when object key value is in array

This is a fast solution with a temporary object.

_x000D_
_x000D_
var records = [{ "empid": 1, "fname": "X", "lname": "Y" }, { "empid": 2, "fname": "A", "lname": "Y" }, { "empid": 3, "fname": "B", "lname": "Y" }, { "empid": 4, "fname": "C", "lname": "Y" }, { "empid": 5, "fname": "C", "lname": "Y" }],_x000D_
    empid = [1, 4, 5],_x000D_
    object = {},_x000D_
    result;_x000D_
_x000D_
records.forEach(function (a) {_x000D_
    object[a.empid] = a;_x000D_
});_x000D_
_x000D_
result = empid.map(function (a) {_x000D_
    return object[a];_x000D_
});_x000D_
document.write('<pre>' + JSON.stringify(result, 0, 4) + '</pre>');
_x000D_
_x000D_
_x000D_

How to match a substring in a string, ignoring case

a = "MandY"
alow = a.lower()
if "mandy" in alow:
    print "true"

work around

Getting attributes of a class

two function:

def get_class_attr(Cls) -> []:
    import re
    return [a for a, v in Cls.__dict__.items()
              if not re.match('<function.*?>', str(v))
              and not (a.startswith('__') and a.endswith('__'))]

def get_class_attr_val(cls):
    attr = get_class_attr(type(cls))
    attr_dict = {}
    for a in attr:
        attr_dict[a] = getattr(cls, a)
    return attr_dict

use:

>>> class MyClass:
    a = "12"
    b = "34"
    def myfunc(self):
        return self.a

>>> m = MyClass()
>>> get_class_attr_val(m)
{'a': '12', 'b': '34'}

How to set the holo dark theme in a Android app?

By default android will set Holo to the Dark theme. There is no theme called Holo.Dark, there's only Holo.Light, that's why you are getting the resource not found error.

So just set it to:

<style name="AppTheme" parent="android:Theme.Holo" />

ASP.NET Identity DbContext confusion

There is a lot of confusion about IdentityDbContext, a quick search in Stackoverflow and you'll find these questions:
" Why is Asp.Net Identity IdentityDbContext a Black-Box?
How can I change the table names when using Visual Studio 2013 AspNet Identity?
Merge MyDbContext with IdentityDbContext"

To answer to all of these questions we need to understand that IdentityDbContext is just a class inherited from DbContext.
Let's take a look at IdentityDbContext source:

/// <summary>
/// Base class for the Entity Framework database context used for identity.
/// </summary>
/// <typeparam name="TUser">The type of user objects.</typeparam>
/// <typeparam name="TRole">The type of role objects.</typeparam>
/// <typeparam name="TKey">The type of the primary key for users and roles.</typeparam>
/// <typeparam name="TUserClaim">The type of the user claim object.</typeparam>
/// <typeparam name="TUserRole">The type of the user role object.</typeparam>
/// <typeparam name="TUserLogin">The type of the user login object.</typeparam>
/// <typeparam name="TRoleClaim">The type of the role claim object.</typeparam>
/// <typeparam name="TUserToken">The type of the user token object.</typeparam>
public abstract class IdentityDbContext<TUser, TRole, TKey, TUserClaim, TUserRole, TUserLogin, TRoleClaim, TUserToken> : DbContext
    where TUser : IdentityUser<TKey, TUserClaim, TUserRole, TUserLogin>
    where TRole : IdentityRole<TKey, TUserRole, TRoleClaim>
    where TKey : IEquatable<TKey>
    where TUserClaim : IdentityUserClaim<TKey>
    where TUserRole : IdentityUserRole<TKey>
    where TUserLogin : IdentityUserLogin<TKey>
    where TRoleClaim : IdentityRoleClaim<TKey>
    where TUserToken : IdentityUserToken<TKey>
{
    /// <summary>
    /// Initializes a new instance of <see cref="IdentityDbContext"/>.
    /// </summary>
    /// <param name="options">The options to be used by a <see cref="DbContext"/>.</param>
    public IdentityDbContext(DbContextOptions options) : base(options)
    { }

    /// <summary>
    /// Initializes a new instance of the <see cref="IdentityDbContext" /> class.
    /// </summary>
    protected IdentityDbContext()
    { }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of Users.
    /// </summary>
    public DbSet<TUser> Users { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of User claims.
    /// </summary>
    public DbSet<TUserClaim> UserClaims { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of User logins.
    /// </summary>
    public DbSet<TUserLogin> UserLogins { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of User roles.
    /// </summary>
    public DbSet<TUserRole> UserRoles { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of User tokens.
    /// </summary>
    public DbSet<TUserToken> UserTokens { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of roles.
    /// </summary>
    public DbSet<TRole> Roles { get; set; }

    /// <summary>
    /// Gets or sets the <see cref="DbSet{TEntity}"/> of role claims.
    /// </summary>
    public DbSet<TRoleClaim> RoleClaims { get; set; }

    /// <summary>
    /// Configures the schema needed for the identity framework.
    /// </summary>
    /// <param name="builder">
    /// The builder being used to construct the model for this context.
    /// </param>
    protected override void OnModelCreating(ModelBuilder builder)
    {
        builder.Entity<TUser>(b =>
        {
            b.HasKey(u => u.Id);
            b.HasIndex(u => u.NormalizedUserName).HasName("UserNameIndex").IsUnique();
            b.HasIndex(u => u.NormalizedEmail).HasName("EmailIndex");
            b.ToTable("AspNetUsers");
            b.Property(u => u.ConcurrencyStamp).IsConcurrencyToken();

            b.Property(u => u.UserName).HasMaxLength(256);
            b.Property(u => u.NormalizedUserName).HasMaxLength(256);
            b.Property(u => u.Email).HasMaxLength(256);
            b.Property(u => u.NormalizedEmail).HasMaxLength(256);
            b.HasMany(u => u.Claims).WithOne().HasForeignKey(uc => uc.UserId).IsRequired();
            b.HasMany(u => u.Logins).WithOne().HasForeignKey(ul => ul.UserId).IsRequired();
            b.HasMany(u => u.Roles).WithOne().HasForeignKey(ur => ur.UserId).IsRequired();
        });

        builder.Entity<TRole>(b =>
        {
            b.HasKey(r => r.Id);
            b.HasIndex(r => r.NormalizedName).HasName("RoleNameIndex");
            b.ToTable("AspNetRoles");
            b.Property(r => r.ConcurrencyStamp).IsConcurrencyToken();

            b.Property(u => u.Name).HasMaxLength(256);
            b.Property(u => u.NormalizedName).HasMaxLength(256);

            b.HasMany(r => r.Users).WithOne().HasForeignKey(ur => ur.RoleId).IsRequired();
            b.HasMany(r => r.Claims).WithOne().HasForeignKey(rc => rc.RoleId).IsRequired();
        });

        builder.Entity<TUserClaim>(b => 
        {
            b.HasKey(uc => uc.Id);
            b.ToTable("AspNetUserClaims");
        });

        builder.Entity<TRoleClaim>(b => 
        {
            b.HasKey(rc => rc.Id);
            b.ToTable("AspNetRoleClaims");
        });

        builder.Entity<TUserRole>(b => 
        {
            b.HasKey(r => new { r.UserId, r.RoleId });
            b.ToTable("AspNetUserRoles");
        });

        builder.Entity<TUserLogin>(b =>
        {
            b.HasKey(l => new { l.LoginProvider, l.ProviderKey });
            b.ToTable("AspNetUserLogins");
        });

        builder.Entity<TUserToken>(b => 
        {
            b.HasKey(l => new { l.UserId, l.LoginProvider, l.Name });
            b.ToTable("AspNetUserTokens");
        });
    }
}


Based on the source code if we want to merge IdentityDbContext with our DbContext we have two options:

First Option:
Create a DbContext which inherits from IdentityDbContext and have access to the classes.

   public class ApplicationDbContext 
    : IdentityDbContext
{
    public ApplicationDbContext()
        : base("DefaultConnection")
    {
    }

    static ApplicationDbContext()
    {
        Database.SetInitializer<ApplicationDbContext>(new ApplicationDbInitializer());
    }

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }

    // Add additional items here as needed
}


Extra Notes:

1) We can also change asp.net Identity default table names with the following solution:

    public class ApplicationDbContext : IdentityDbContext
    {    
        public ApplicationDbContext(): base("DefaultConnection")
        {
        }

        protected override void OnModelCreating(System.Data.Entity.DbModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            modelBuilder.Entity<IdentityUser>().ToTable("user");
            modelBuilder.Entity<ApplicationUser>().ToTable("user");

            modelBuilder.Entity<IdentityRole>().ToTable("role");
            modelBuilder.Entity<IdentityUserRole>().ToTable("userrole");
            modelBuilder.Entity<IdentityUserClaim>().ToTable("userclaim");
            modelBuilder.Entity<IdentityUserLogin>().ToTable("userlogin");
        }
    }

2) Furthermore we can extend each class and add any property to classes like 'IdentityUser', 'IdentityRole', ...

    public class ApplicationRole : IdentityRole<string, ApplicationUserRole>
{
    public ApplicationRole() 
    {
        this.Id = Guid.NewGuid().ToString();
    }

    public ApplicationRole(string name)
        : this()
    {
        this.Name = name;
    }

    // Add any custom Role properties/code here
}


// Must be expressed in terms of our custom types:
public class ApplicationDbContext 
    : IdentityDbContext<ApplicationUser, ApplicationRole, 
    string, ApplicationUserLogin, ApplicationUserRole, ApplicationUserClaim>
{
    public ApplicationDbContext()
        : base("DefaultConnection")
    {
    }

    static ApplicationDbContext()
    {
        Database.SetInitializer<ApplicationDbContext>(new ApplicationDbInitializer());
    }

    public static ApplicationDbContext Create()
    {
        return new ApplicationDbContext();
    }

    // Add additional items here as needed
}

To save time we can use AspNet Identity 2.0 Extensible Project Template to extend all the classes.

Second Option:(Not recommended)
We actually don't have to inherit from IdentityDbContext if we write all the code ourselves.
So basically we can just inherit from DbContext and implement our customized version of "OnModelCreating(ModelBuilder builder)" from the IdentityDbContext source code

Bootstrap modal: close current, open new

As mentioned above In the html in the same button, you can ask to close the current modal with data-dismiss and open a new modal directly with data-target:

<button class="btn btn-success" data-toggle="modal" data-target="#modalRegistration" data-dismiss="modal">Register</button>

But this will cause scroll-bar disappear and you will notice that if the second modal was longer that the first one

So the solution is to add the following style in the modal inline style :

Style = "overflow-y : scroll ; "

How to get a resource id with a known resource name?

If I understood right, this is what you want

int drawableResourceId = this.getResources().getIdentifier("nameOfDrawable", "drawable", this.getPackageName());

Where "this" is an Activity, written just to clarify.

In case you want a String in strings.xml or an identifier of a UI element, substitute "drawable"

int resourceId = this.getResources().getIdentifier("nameOfResource", "id", this.getPackageName());

I warn you, this way of obtaining identifiers is really slow, use only where needed.

Link to official documentation: Resources.getIdentifier(String name, String defType, String defPackage)

getElementsByClassName not working

If you want to do it by ClassName you could do:

<script type="text/javascript">
function hideTd(className){
    var elements;

    if (document.getElementsByClassName)
    {
        elements = document.getElementsByClassName(className);
    }
    else
    {
        var elArray = [];
        var tmp = document.getElementsByTagName(elements);  
        var regex = new RegExp("(^|\\s)" + className+ "(\\s|$)");
        for ( var i = 0; i < tmp.length; i++ ) {

            if ( regex.test(tmp[i].className) ) {
                elArray.push(tmp[i]);
            }
        }

        elements = elArray;
    }

    for(var i = 0, i < elements.length; i++) {
       if( elements[i].textContent == ''){
          elements[i].style.display = 'none';
       } 
    }

  }
</script>

Command failed due to signal: Segmentation fault: 11

I had similar issue in with Xcode 7.3 and iOS 9.3. Command failed due to signal: Segmentation fault: 11

Screenshot

Basic steps such as Clean (cmd+shift+k) code, Delete derived data and Quit Xcode didn't work.

There was some culprit in my code.

It was [txtUserName.text.characters.count = 0]

In your case Review your code and fix the culprit.

How can I get current date in Android?

just one line code to get simple Date format :

SimpleDateFormat.getDateInstance().format(Date())

output : 18-May-2020

SimpleDateFormat.getDateTimeInstance().format(Date())

output : 18-May-2020 11:00:39 AM

SimpleDateFormat.getTimeInstance().format(Date())

output : 11:00:39 AM

Hope this answer is enough to get this Date and Time Format ... :)

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

Using Anaconda + Spyder (Python 3.7)

[code]

import tensorflow as tf
valor1 = tf.constant(2)
valor2 = tf.constant(3)
type(valor1)
print(valor1)
soma=valor1+valor2
type(soma)
print(soma)
sess = tf.compat.v1.Session()
with sess:
    print(sess.run(soma))

[console]

import tensorflow as tf
valor1 = tf.constant(2)
valor2 = tf.constant(3)
type(valor1)
print(valor1)
soma=valor1+valor2
type(soma)
Tensor("Const_8:0", shape=(), dtype=int32)
Out[18]: tensorflow.python.framework.ops.Tensor

print(soma)
Tensor("add_4:0", shape=(), dtype=int32)

sess = tf.compat.v1.Session()

with sess:
    print(sess.run(soma))
5

Add 10 seconds to a Date

  1. you can use setSeconds method by getting seconds from today and just adding 10 seconds in it

    var today = new Date();
    today.setSeconds(today.getSeconds() + 10);
    
  2. You can add 10 *1000 milliseconds to the new date:

    var today = new Date(); 
    today = new Date(today.getTime() + 1000*10);
    
  3. You can use setTime:

    today.setTime(now.getTime() + 10000)
    

YAML Multi-Line Arrays

have you tried this?

-
  name: Jack
  age: 32
-
  name: Claudia
  age: 25

I get this: [{"name"=>"Jack", "age"=>32}, {"name"=>"Claudia", "age"=>25}] (I use the YAML Ruby class).

C++ equivalent of Java's toString?

As an extension to what John said, if you want to extract the string representation and store it in a std::string do this:

#include <sstream>    
// ...
// Suppose a class A
A a;
std::stringstream sstream;
sstream << a;
std::string s = sstream.str(); // or you could use sstream >> s but that would skip out whitespace

std::stringstream is located in the <sstream> header.

How to Clone Objects

a and b are just two references to the same Person object. They both essentially hold the address of the Person.

There is a ICloneable interface, though relatively few classes support it. With this, you would write:

Person b = a.Clone();

Then, b would be an entirely separate Person.

You could also implement a copy constructor:

public Person(Person src)
{
  // ... 
}

There is no built-in way to copy all the fields. You can do it through reflection, but there would be a performance penalty.

Send JSON via POST in C# and Receive the JSON returned?

You can also use the PostAsJsonAsync() method available in HttpClient()

_x000D_
_x000D_
   var requestObj= JsonConvert.SerializeObject(obj);_x000D_
   HttpResponseMessage response = await    client.PostAsJsonAsync($"endpoint",requestObj).ConfigureAwait(false);
_x000D_
_x000D_
_x000D_

How to define Gradle's home in IDEA?

If you're using MacPorts, the path is

/opt/local/share/java/gradle

How to get the Parent's parent directory in Powershell?

You can use

(get-item $scriptPath).Directoryname

to get the string path or if you want the Directory type use:

(get-item $scriptPath).Directory

How to draw a graph in LaTeX?

I have used graphviz ( https://www.graphviz.org/gallery ) together with LaTeX using dot command to generate graphs in PDF and includegraphics to include those.

If graphviz produces what you are aiming at, this might be the best way to integrate: dot2tex: https://ctan.org/pkg/dot2tex?lang=en

Why does JavaScript only work after opening developer tools in IE once?

If you are using AngularJS version 1.X you could use the $log service instead of using console.log directly.

Simple service for logging. Default implementation safely writes the message into the browser's console (if present).

https://docs.angularjs.org/api/ng/service/$log

So if you have something similar to

angular.module('logExample', [])
  .controller('LogController', ['$scope', function($scope) {
    console.log('Hello World!');
 }]);

you can replace it with

angular.module('logExample', [])
  .controller('LogController', ['$scope', '$log', function($scope, $log) {
    $log.log('Hello World!');
 }]);

Angular 2+ does not have any built-in log service.

Non-recursive depth first search algorithm

An ES6 implementation based on biziclops great answer:

_x000D_
_x000D_
root = {_x000D_
  text: "root",_x000D_
  children: [{_x000D_
    text: "c1",_x000D_
    children: [{_x000D_
      text: "c11"_x000D_
    }, {_x000D_
      text: "c12"_x000D_
    }]_x000D_
  }, {_x000D_
    text: "c2",_x000D_
    children: [{_x000D_
      text: "c21"_x000D_
    }, {_x000D_
      text: "c22"_x000D_
    }]_x000D_
  }, ]_x000D_
}_x000D_
_x000D_
console.log("DFS:")_x000D_
DFS(root, node => node.children, node => console.log(node.text));_x000D_
_x000D_
console.log("BFS:")_x000D_
BFS(root, node => node.children, node => console.log(node.text));_x000D_
_x000D_
function BFS(root, getChildren, visit) {_x000D_
  let nodesToVisit = [root];_x000D_
  while (nodesToVisit.length > 0) {_x000D_
    const currentNode = nodesToVisit.shift();_x000D_
    nodesToVisit = [_x000D_
      ...nodesToVisit,_x000D_
      ...(getChildren(currentNode) || []),_x000D_
    ];_x000D_
    visit(currentNode);_x000D_
  }_x000D_
}_x000D_
_x000D_
function DFS(root, getChildren, visit) {_x000D_
  let nodesToVisit = [root];_x000D_
  while (nodesToVisit.length > 0) {_x000D_
    const currentNode = nodesToVisit.shift();_x000D_
    nodesToVisit = [_x000D_
      ...(getChildren(currentNode) || []),_x000D_
      ...nodesToVisit,_x000D_
    ];_x000D_
    visit(currentNode);_x000D_
  }_x000D_
}
_x000D_
_x000D_
_x000D_

Working with INTERVAL and CURDATE in MySQL

You need DATE_ADD/DATE_SUB:

AND v.date > (DATE_SUB(CURDATE(), INTERVAL 2 MONTH))
AND v.date < (DATE_SUB(CURDATE(), INTERVAL 1 MONTH))

should work.

How can I get jQuery to perform a synchronous, rather than asynchronous, Ajax request?

You can put the jQuery's Ajax setup in synchronous mode by calling

jQuery.ajaxSetup({async:false});

And then perform your Ajax calls using jQuery.get( ... );

Then just turning it on again once

jQuery.ajaxSetup({async:true});

I guess it works out the same thing as suggested by @Adam, but it might be helpful to someone that does want to reconfigure their jQuery.get() or jQuery.post() to the more elaborate jQuery.ajax() syntax.

Simple URL GET/POST function in Python

import urllib

def fetch_thing(url, params, method):
    params = urllib.urlencode(params)
    if method=='POST':
        f = urllib.urlopen(url, params)
    else:
        f = urllib.urlopen(url+'?'+params)
    return (f.read(), f.code)


content, response_code = fetch_thing(
                              'http://google.com/', 
                              {'spam': 1, 'eggs': 2, 'bacon': 0}, 
                              'GET'
                         )

[Update]

Some of these answers are old. Today I would use the requests module like the answer by robaple.

How do you create an asynchronous HTTP request in JAVA?

Note that java11 now offers a new HTTP api HttpClient, which supports fully asynchronous operation, using java's CompletableFuture.

It also supports a synchronous version, with calls like send, which is synchronous, and sendAsync, which is asynchronous.

Example of an async request (taken from the apidoc):

   HttpRequest request = HttpRequest.newBuilder()
        .uri(URI.create("https://example.com/"))
        .timeout(Duration.ofMinutes(2))
        .header("Content-Type", "application/json")
        .POST(BodyPublishers.ofFile(Paths.get("file.json")))
        .build();
   client.sendAsync(request, BodyHandlers.ofString())
        .thenApply(HttpResponse::body)
        .thenAccept(System.out::println);

Convert iterator to pointer?

A safe version to convert an iterator to a pointer (exactly what that means regardless of the implications) and by safe I mean no worries about having to dereference the iterator and cause possible exceptions / errors due to end() / other situations

#include <iostream>
#include <vector>
#include <string.h>

int main()
{
    std::vector<int> vec;

    char itPtr[25];
    long long itPtrDec;
    
    std::vector<int>::iterator it = vec.begin();
    memset(&itPtr, 0, 25);
    sprintf(itPtr, "%llu", it);
    itPtrDec = atoll(itPtr);
    printf("it = 0x%X\n", itPtrDec);
    
    vec.push_back(123);
    it = vec.begin();
    memset(&itPtr, 0, 25);
    sprintf(itPtr, "%llu", it);
    itPtrDec = atoll(itPtr);
    printf("it = 0x%X\n", itPtrDec);
}

will print something like

it = 0x0

it = 0x2202E10

It's an incredibly hacky way to do it, but if you need it, it does the job. You will receive some compiler warnings which, if really bothering you, can be removed with #pragma

Comparing two strings in C?

To answer the WHY in your question:

Because the equality operator can only be applied to simple variable types, such as floats, ints, or chars, and not to more sophisticated types, such as structures or arrays. To determine if two strings are equal, you must explicitly compare the two character strings character by character.

MongoDB - admin user not authorized

I had this problem because of the hostname in my MongoDB Compass was pointing to admin instead for my project. Fixed by adding the /projectname after the hostname :) Try this:

  1. Choose your project in the MongoDB atlas website
  2. Connect/Connect with MongoDB Compass
  3. Download Compass/Choose your OS
  4. I used Compass 1.12 or later
  5. Copy the connection string under the Compass 1.12 or later.
  6. Open MongoDB Compass/Connect(top left)/Connect To
  7. Connection String detected/Yes/
  8. Append your project name after the hostname: cluster9-foodie.mongodb.net/projectname
  9. Connect & Tested the API with POSTMAN.
  10. Succeed.

Use the same connection string in your code too:

  1. Before:
    • mongodb+srv://projectname:password@cluster9-foodie.mongodb.net/admin
  2. After:
    • mongodb+srv://projectname:password@cluster9-foodie.mongodb.net/projectname

Good luck.

C#: How to make pressing enter in a text box trigger a button, yet still allow shortcuts such as "Ctrl+A" to get through?

You can Use KeyPress instead of KeyUp or KeyDown its more efficient and here's how to handle

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
    {
        if (e.KeyChar == (char)Keys.Enter)
        {
            e.Handled = true;
            button1.PerformClick();
        }
    }

hope it works

How to get just the parent directory name of a specific file

File file = new File("C:/aaa/bbb/ccc/ddd/test.java");
File curentPath = new File(file.getParent());
//get current path "C:/aaa/bbb/ccc/ddd/"
String currentFolder= currentPath.getName().toString();
//get name of file to string "ddd"

if you need to append folder "ddd" by another path use;

String currentFolder= "/" + currentPath.getName().toString();

Communication between multiple docker-compose projects

You just need to make sure that the containers you want to talk to each other are on the same network. Networks are a first-class docker construct, and not specific to compose.

# front/docker-compose.yml
version: '2'
services:
  front:
    ...
    networks:
      - some-net
networks:
  some-net:
    driver: bridge

...

# api/docker-compose.yml
version: '2'
services:
  api:
    ...
    networks:
      - front_some-net
networks:
  front_some-net:
    external: true

Note: Your app’s network is given a name based on the “project name”, which is based on the name of the directory it lives in, in this case a prefix front_ was added

They can then talk to each other using the service name. From front you can do ping api and vice versa.

R command for setting working directory to source file location in Rstudio

I know this question is outdated, but I was searching for a solution for that as well and Google lists this at the very top:

this.dir <- dirname(parent.frame(2)$ofile)
setwd(this.dir)

put that somewhere into the file (best would be the beginning, though), so that the wd is changed according to that file.

According to the comments, this might not necessarily work on every platform (Windows seems to work, Linux/Mac for some). Keep in mind that this solution is for 'sourcing' the files, not necessarily for running chunks in that file.

see also get filename and path of `source`d file

C# Numeric Only TextBox Control

TRY THIS CODE

// Boolean flag used to determine when a character other than a number is entered.
private bool nonNumberEntered = false;
// Handle the KeyDown event to determine the type of character entered into the control.
private void textBox1_KeyDown(object sender, KeyEventArgs e)
{
    // Initialize the flag to false.
    nonNumberEntered = false;
    // Determine whether the keystroke is a number from the top of the keyboard.
    if (e.KeyCode < Keys.D0 || e.KeyCode > Keys.D9)
    {
        // Determine whether the keystroke is a number from the keypad.
        if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)
        {
            // Determine whether the keystroke is a backspace.
            if (e.KeyCode != Keys.Back)
            {
                // A non-numerical keystroke was pressed.
                // Set the flag to true and evaluate in KeyPress event.
                nonNumberEntered = true;
            }
        }
    }
}

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
{
    if (nonNumberEntered == true)
    {
       MessageBox.Show("Please enter number only..."); 
       e.Handled = true;
    }
}


Source is http://msdn.microsoft.com/en-us/library/system.windows.forms.control.keypress(v=VS.90).aspx

Floating point exception( core dump

You are getting Floating point exception because Number % i, when i is 0:

int Is_Prime( int Number ){

  int i ;

  for( i = 0 ; i < Number / 2 ; i++ ){

    if( Number % i != 0 ) return -1 ;

  }

  return Number ;

}

Just start the loop at i = 2. Since i = 1 in Number % i it always be equal to zero, since Number is a int.

How to select the nth row in a SQL database table?

I'm a bit late to the party here but I have done this without the need for windowing or using

WHERE x IN (...)
SELECT TOP 1
--select the value needed from t1
[col2]
FROM
(
   SELECT TOP 2 --the Nth row, alter this to taste
   UE2.[col1],
   UE2.[col2],
   UE2.[date],
   UE2.[time],
   UE2.[UID]
   FROM
   [table1] AS UE2
   WHERE
   UE2.[col1] = ID --this is a subquery 
   AND
   UE2.[col2] IS NOT NULL
   ORDER BY
   UE2.[date] DESC, UE2.[time] DESC --sorting by date and time newest first
) AS t1
ORDER BY t1.[date] ASC, t1.[time] ASC --this reverses the order of the sort in t1

It seems to work fairly fast although to be fair I only have around 500 rows of data

This works in MSSQL

How to find the mime type of a file in python?

The mimetypes module in the standard library will determine/guess the MIME type from a file extension.

If users are uploading files the HTTP post will contain the MIME type of the file alongside the data. For example, Django makes this data available as an attribute of the UploadedFile object.

Python how to exit main function

If you don't feel like importing anything, you can try:

raise SystemExit, 0

How to generate a random number between 0 and 1?

In your version rand() % 10000 will yield an integer between 0 and 9999. Since RAND_MAX may be as little as 32767, and since this is not exactly divisible by 10000 and not large relative to 10000, there will be significant bias in the 'randomness' of the result, moreover, the maximum value will be 0.9999, not 1.0, and you have unnecessarily restricted your values to four decimal places.

It is simple arithmetic, a random number divided by the maximum possible random number will yield a number from 0 to 1 inclusive, while utilising the full resolution and distribution of the RNG

double r2()
{
    return (double)rand() / (double)RAND_MAX ;
}

Use (double)rand() / (double)((unsigned)RAND_MAX + 1) if exclusion of 1.0 was intentional.

Where does Android emulator store SQLite database?

Simple Solution - works for both Emulator & Connected Devices

1 See the list of devices/emulators currently available.

$ adb devices

List of devices attached

G7NZCJ015313309 device emulator-5554 device

9885b6454e46383744 device

2 Run backup on your device/emulator

$ adb -s emulator-5554 backup -f ~/Desktop/data.ab -noapk com.your_app_package.app;

3 Extract data.ab

$ dd if=data.ab bs=1 skip=24 | openssl zlib -d | tar -xvf -;

You will find the database in /db folder

What are Java command line options to set to allow JVM to be remotely debugged?

Here is the easiest solution.

There are a lot of environment special configurations needed if you are using Maven. So, if you start your program from maven, just run the mvnDebug command instead of mvn, it will take care of starting your app with remote debugging configurated. Now you can just attach a debugger on port 8000.

It'll take care of all the environment problems for you.

HTML Input Box - Disable

The syntax to disable an HTML input is as follows:

<input type="text" id="input_id" DISABLED />

How do you create optional arguments in php?

If you don't know how many attributes need to be processed, you can use the variadic argument list token(...) introduced in PHP 5.6 (see full documentation here).

Syntax:

function <functionName> ([<type> ]...<$paramName>) {}

For example:

function someVariadricFunc(...$arguments) {
  foreach ($arguments as $arg) {
    // do some stuff with $arg...
  }
}

someVariadricFunc();           // an empty array going to be passed
someVariadricFunc('apple');    // provides a one-element array
someVariadricFunc('apple', 'pear', 'orange', 'banana');

As you can see, this token basically turns all parameters to an array, which you can process in any way you like.

How to return a 200 HTTP Status Code from ASP.NET MVC 3 controller

You can simply set the status code of the response to 200 like the following

public ActionResult SomeMethod(parameters...)
{
   //others code here
   ...      
   Response.StatusCode = 200;
   return YourObject;  
}

How to convert "Mon Jun 18 00:00:00 IST 2012" to 18/06/2012?

Just need to add: new SimpleDateFormat("bla bla bla", Locale.US)

public static void main(String[] args) throws ParseException {
    java.util.Date fecha = new java.util.Date("Mon Dec 15 00:00:00 CST 2014");
    DateFormat formatter = new SimpleDateFormat("EEE MMM dd HH:mm:ss Z yyyy", Locale.US);
    Date date;
    date = (Date)formatter.parse(fecha.toString());
    System.out.println(date);        

    Calendar cal = Calendar.getInstance();
    cal.setTime(date);
    String formatedDate = cal.get(Calendar.DATE) + "/" + 
            (cal.get(Calendar.MONTH) + 1) + 
            "/" +         cal.get(Calendar.YEAR);
    System.out.println("formatedDate : " + formatedDate);
}

How to copy a string of std::string type in C++?

Caesar's solution is the best in my opinion, but if you still insist to use the strcpy function, then after you have your strings ready:

string a = "text";
string b = "image";

You can try either:

strcpy(a.data(), b.data());

or

strcpy(a.c_str(), b.c_str());

Just call either the data() or c_str() member functions of the std::string class, to get the char* pointer of the string object.

The strcpy() function doesn't have overload to accept two std::string objects as parameters. It has only one overload to accept two char* pointers as parameters.

Both data and c_str return what does strcpy() want exactly.

What are the obj and bin folders (created by Visual Studio) used for?

The obj directory is for intermediate object files and other transient data files that are generated by the compiler or build system during a build. The bin directory is the directory that final output binaries (and any dependencies or other deployable files) will be written to.

You can change the actual directories used for both purposes within the project settings, if you like.

In .NET, which loop runs faster, 'for' or 'foreach'?

I did test it a while ago, with the result that a for loop is much faster than a foreach loop. The cause is simple, the foreach loop first needs to instantiate an IEnumerator for the collection.

How do I get console input in javascript?

In plain JavaScript, simply use response = readline() after printing a prompt.

In Node.js, you'll need to use the readline module: const readline = require('readline')

SQL Server principal "dbo" does not exist,

As the message said, you should set permission as owner to your user. So you can use following:

ALTER AUTHORIZATION 
ON DATABASE::[YourDBName]
TO [UserLogin];

Hope helpful! Leave comment if it's ok for you.

What is the difference between Visual Studio Express 2013 for Windows and Visual Studio Express 2013 for Windows Desktop?

More importantly, the 2013 versions of Visual Studio Express have all the languages that comes with the commercial versions. You can use the Windows desktop versions not only to program using Windows Forms, it is possible to write those windowed applications with any language that comes with the software, may it be C++ using the windows.h header if you want to actually learn how to create windows applications from scratch, or use Windows form to create windows in C# or visual Basic.

In the past, you had to download one version for each language or type of content. Or just download an all-in-one that still installed separate versions of the software for different languages. Now with 2013 you get all the languages needed in each content oriented version of the 2013 express.

You pick what matters the most to you.

Besides, it might be a good way to learn using notepad and the command line to write and compile, but I find that a bit tedious to use. While using an IDE might be overwhelming at first, you start small, learning how to create a project, write code, compile your code. They have gone way over their heads to ease up your day when you take it for the first time.

MySQL root password change

I searched around as well and probably some answers do fit for some situations,

my situation is Mysql 5.7 on a Ubuntu 18.04.2 LTS system:

(get root privileges)

$ sudo bash

(set up password for root db user + implement security in steps)

# mysql_secure_installation

(give access to the root user via password in stead of socket)

(+ edit: apparently you need to set the password again?)

(don't set it to 'mySecretPassword'!!!)

# mysql -u root

mysql> USE mysql;
mysql> UPDATE user SET plugin='mysql_native_password' WHERE User='root';
mysql> set password for 'root'@'localhost' = PASSWORD('mySecretPassword'); 
mysql> FLUSH PRIVILEGES;
mysql> exit;

# service mysql restart

Many thanks to zetacu (and erich) for this excellent answer (after searching a couple of hours...)

Enjoy :-D

S.

Edit (2020):

This method doesn't work anymore, see this question for future reference...

Eliminating NAs from a ggplot

Just an update to the answer of @rafa.pereira. Since ggplot2 is part of tidyverse, it makes sense to use the convenient tidyverse functions to get rid of NAs.

library(tidyverse)
airquality %>% 
        drop_na(Ozone) %>%
        ggplot(aes(x = Ozone))+
        geom_bar(stat="bin")

Note that you can also use drop_na() without columns specification; then all the rows with NAs in any column will be removed.

Convert string with comma to integer

If someone is looking to sub out more than a comma I'm a fan of:

"1,200".chars.grep(/\d/).join.to_i

dunno about performance but, it is more flexible than a gsub, ie:

"1-200".chars.grep(/\d/).join.to_i

PSEXEC, access denied errors

For anybody who may stumble upon this. There is a recent (Dec 2013) Security Update from Microsoft Windows on Windows 7 that is preventing remote execution. See http://support.microsoft.com/kb/2893294/en-us

I uninstalled the Security Update by going to Control Panel\Programs\Programs and Features\Installed Updates

It worked right after that.

Remove all items from RecyclerView

On Xamarin.Android, It works for me and need change layout

 var layout = recyclerView.GetLayoutManager() as GridLayoutManager;
 layout.SpanCount = GetItemPerRow(Context);
 recyclerView.SetAdapter(null);
 recyclerView.SetAdapter(adapter); //reset

use current date as default value for a column

Add a default constraint with the GETDATE() function as value.

ALTER TABLE myTable 
  ADD CONSTRAINT CONSTRAINT_NAME
    DEFAULT GETDATE() FOR myColumn

What is JSON and why would I use it?

In short, it is a scripting notation for passing data about. In some ways an alternative to XML, natively supporting basic data types, arrays and associative arrays (name-value pairs, called Objects because that is what they represent).

The syntax is that used in JavaScript and JSON itself stands for "JavaScript Object Notation". However it has become portable and is used in other languages too.

A useful link for detail is here:

http://secretgeek.net/json_3mins.asp

How to insert a column in a specific position in oracle without dropping and recreating the table?

In 12c you can make use of the fact that columns which are set from invisible to visible are displayed as the last column of the table: Tips and Tricks: Invisible Columns in Oracle Database 12c

Maybe that is the 'trick' @jeffrey-kemp was talking about in his comment, but the link there does not work anymore.

Example:

ALTER TABLE my_tab ADD (col_3 NUMBER(10));
ALTER TABLE my_tab MODIFY (
  col_1 invisible,
  col_2 invisible
);
ALTER TABLE my_tab MODIFY (
  col_1 visible,
  col_2 visible
);

Now col_3 would be displayed first in a SELECT * FROM my_tab statement.

Note: This does not change the physical order of the columns on disk, but in most cases that is not what you want to do anyway. If you really want to change the physical order, you can use the DBMS_REDEFINITION package.

How can javascript upload a blob?

I tried all the solutions above and in addition, those in related answers as well. Solutions including but not limited to passing the blob manually to a HTMLInputElement's file property, calling all the readAs* methods on FileReader, using a File instance as second argument for a FormData.append call, trying to get the blob data as a string by getting the values at URL.createObjectURL(myBlob) which turned out nasty and crashed my machine.

Now, if you happen to attempt those or more and still find you're unable to upload your blob, it could mean the problem is server-side. In my case, my blob exceeded the http://www.php.net/manual/en/ini.core.php#ini.upload-max-filesize and post_max_size limit in PHP.INI so the file was leaving the front end form but getting rejected by the server. You could either increase this value directly in PHP.INI or via .htaccess

Sorted collection in Java

Use sort() method to sort the list as below:

List list = new ArrayList();

//add elements to the list

Comparator comparator = new SomeComparator();

Collections.sort(list, comparator);

For reference see the link: http://tutorials.jenkov.com/java-collections/sorting.html

Unsupported major.minor version 52.0

If you have a problem in Android Studio and you have installed Android N, change the Android rendering version with an older one and the problem will disappear.

Enter image description here

How Can I Set the Default Value of a Timestamp Column to the Current Timestamp with Laravel Migrations?

I use the following customization in Laravel to:

  1. Default created_at to the current timestamp
  2. Update the timestamp when the record is updated

First, I'll create a file, helpers.php, in the root of Laravel and insert the following:

<?php

if (!function_exists('database_driver')) {
    function database_driver(): string
    {
        $connection = config('database.default');
        return config('database.connections.' . $connection . '.driver');
    }
}

if (!function_exists('is_database_driver')) {
    function is_database_driver(string $driver): bool
    {
        return $driver === database_driver();
    }
}

In composer.json, I'll insert the following into autoload. This allows composer to auto-discover helpers.php.

    "autoload": {
        "files": [
            "app/Services/Uploads/Processors/processor_functions.php",
            "app/helpers.php"
        ]
    },

I use the following in my Laravel models.

        if (is_database_driver('sqlite')) {
            $table->timestamps();
        } else {
            $table->timestamp('created_at')->default(\DB::raw('CURRENT_TIMESTAMP'));
            $table->timestamp('updated_at')
                ->default(DB::raw('CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP'));
        }

This allows my team to continue using sqlite for unit tests. ON UPDATE CURRENT_TIMESTAMP is a MySQL shortcut and is not available in sqlite.

Programmatically scroll a UIScrollView

If you want control over the duration and style of the animation, you can do:

[UIView animateWithDuration:2.0f delay:0 options:UIViewAnimationOptionCurveLinear animations:^{
    scrollView.contentOffset = CGPointMake(x, y);
} completion:NULL];

Adjust the duration (2.0f) and options (UIViewAnimationOptionCurveLinear) to taste!

Why doesn't the height of a container element increase if it contains floated elements?

You need to add overflow:auto to your parent div for it to encompass the inner floated div:

<div style="margin:0 auto;width: 960px; min-height: 100px; background-color:orange;overflow:auto">
    <div style="width:500px; height:200px; background-color:black; float:right">
    </div>
</div>

jsFiddle example

What's the best practice using a settings file in Python?

You can have a regular Python module, say config.py, like this:

truck = dict(
    color = 'blue',
    brand = 'ford',
)
city = 'new york'
cabriolet = dict(
    color = 'black',
    engine = dict(
        cylinders = 8,
        placement = 'mid',
    ),
    doors = 2,
)

and use it like this:

import config
print(config.truck['color'])  

Understanding the difference between Object.create() and new SomeFunction()

function Test(){
    this.prop1 = 'prop1';
    this.prop2 = 'prop2';
    this.func1 = function(){
        return this.prop1 + this.prop2;
    }
};

Test.prototype.protoProp1 = 'protoProp1';
Test.prototype.protoProp2 = 'protoProp2';
var newKeywordTest = new Test();
var objectCreateTest = Object.create(Test.prototype);

/* Object.create   */
console.log(objectCreateTest.prop1); // undefined
console.log(objectCreateTest.protoProp1); // protoProp1 
console.log(objectCreateTest.__proto__.protoProp1); // protoProp1

/* new    */
console.log(newKeywordTest.prop1); // prop1
console.log(newKeywordTest.__proto__.protoProp1); // protoProp1

Summary:

1) with new keyword there are two things to note;

a) function is used as a constructor

b) function.prototype object is passed to the __proto__ property ... or where __proto__ is not supported, it is the second place where the new object looks to find properties

2) with Object.create(obj.prototype) you are constructing an object (obj.prototype) and passing it to the intended object ..with the difference that now new object's __proto__ is also pointing to obj.prototype (please ref ans by xj9 for that)

Iterating each character in a string using Python

Even easier:

for c in "test":
    print c

Best way to split string into lines

    private string[] GetLines(string text)
    {

        List<string> lines = new List<string>();
        using (MemoryStream ms = new MemoryStream())
        {
            StreamWriter sw = new StreamWriter(ms);
            sw.Write(text);
            sw.Flush();

            ms.Position = 0;

            string line;

            using (StreamReader sr = new StreamReader(ms))
            {
                while ((line = sr.ReadLine()) != null)
                {
                    lines.Add(line);
                }
            }
            sw.Close();
        }



        return lines.ToArray();
    }

jQuery Uncaught TypeError: Property '$' of object [object Window] is not a function

My favorite no-conflict-friendly construct:

jQuery(function($) {
  // ...
});

Calling jQuery with a function pointer is a shortcut for $(document).ready(...)

Or as we say in coffeescript:

jQuery ($) ->
  # code here

How do I cancel form submission in submit button onclick event?

Sometimes onsubmit wouldn't work with asp.net.

I solved it with very easy way.

if we have such a form

<form method="post" name="setting-form" >
   <input type="text" id="UserName" name="UserName" value="" 
      placeholder="user name" >
   <input type="password" id="Password" name="password" value="" placeholder="password" >
   <div id="remember" class="checkbox">
    <label>remember me</label>
    <asp:CheckBox ID="RememberMe" runat="server" />
   </div>
   <input type="submit" value="login" id="login-btn"/>
</form>

You can now catch get that event before the form postback and stop it from postback and do all the ajax you want using this jquery.

$(document).ready(function () {
            $("#login-btn").click(function (event) {
                event.preventDefault();
                alert("do what ever you want");
            });
 });

jQuery UI DatePicker - Change Date Format

This is what worked for me:

$.fn.datepicker.defaults.format = 'yy-mm-dd'

mvn clean install vs. deploy vs. release

  • mvn install will put your packaged maven project into the local repository, for local application using your project as a dependency.
  • mvn release will basically put your current code in a tag on your SCM, change your version in your projects.
  • mvn deploy will put your packaged maven project into a remote repository for sharing with other developers.

Resources :

C++ sorting and keeping track of indexes

Make a std::pair in function then sort pair :

generic version :

template< class RandomAccessIterator,class Compare >
auto sort2(RandomAccessIterator begin,RandomAccessIterator end,Compare cmp) ->
   std::vector<std::pair<std::uint32_t,RandomAccessIterator>>
{
    using valueType=typename std::iterator_traits<RandomAccessIterator>::value_type;
    using Pair=std::pair<std::uint32_t,RandomAccessIterator>;

    std::vector<Pair> index_pair;
    index_pair.reserve(std::distance(begin,end));

    for(uint32_t idx=0;begin!=end;++begin,++idx){
        index_pair.push_back(Pair(idx,begin));
    }

    std::sort( index_pair.begin(),index_pair.end(),[&](const Pair& lhs,const Pair& rhs){
          return cmp(*lhs.second,*rhs.second);
    });

    return index_pair;
}

ideone

Why is it common to put CSRF prevention tokens in cookies?

Using a cookie to provide the CSRF token to the client does not allow a successful attack because the attacker cannot read the value of the cookie and therefore cannot put it where the server-side CSRF validation requires it to be.

The attacker will be able to cause a request to the server with both the auth token cookie and the CSRF cookie in the request headers. But the server is not looking for the CSRF token as a cookie in the request headers, it's looking in the payload of the request. And even if the attacker knows where to put the CSRF token in the payload, they would have to read its value to put it there. But the browser's cross-origin policy prevents reading any cookie value from the target website.

The same logic does not apply to the auth token cookie, because the server is expects it in the request headers and the attacker does not have to do anything special to put it there.

Waiting for another flutter command to release the startup lock

For Newbies

The simplest solution, although a little time consuming would be to restart your computer or simple logout from the current user and login again.

How to view file diff in git before commit

The best way I found, aside of using a dedicated commit GUI, is to use git difftool -d - This opens your diff tool in directory comparison mode, comparing HEAD with current dirty folder.

Compiling php with curl, where is curl installed?

Try just --with-curl, without specifying a location, and see if it'll find it by itself.

Javascript Click on Element by Class

class of my button is "input-addon btn btn-default fileinput-exists"

below code helped me

document.querySelector('.input-addon.btn.btn-default.fileinput-exists').click();

but I want to click second button, I have two buttons in my screen so I used querySelectorAll

var elem = document.querySelectorAll('.input-addon.btn.btn-default.fileinput-exists');
                elem[1].click();

here elem[1] is the second button object that I want to click.