Programs & Examples On #Installanywhere

A multi-platform deployment solution that will allow your application to be deployed on any platform.

Windows error 2 occured while loading the Java VM

I had same mistake, it was produced because i had disabled the creation of "_jvm" in the InstallAnywhere (project - JVM settings - Installer Settings - Bundled/Downloaded Virtual Machine), then into file "Uninstall $PRODUCT_NAME$.lax" into uninstall folder, the variable "lax.nl.current.vm" is empty.

If you don't need jvm is disabled check "Install Bundled / Downloaded Virtual Machine" option in the checkbox (project - JVM settings - Installer Settings - Bundled/Downloaded Virtual Machine).

If you need jvm is disabled because you create it manually, then you can do the following: create an action "Modify Text File" to append variable with the value of the _jvm folder.

(Existing File)
$USER_INSTALL_DIR$\Uninstall_$PRODUCT_NAME$ \Uninstall $PRODUCT_NAME$.lax

(Append)

lax.nl.current.vm=..\_jvm\bin\java.exe

How to search for a string in an arraylist

Nowadays, Java 8 allows for a one-line functional solution that is cleaner, faster, and a whole lot simpler than the accepted solution:

List<String> list = new ArrayList<>();
list.add("behold");
list.add("bend");
list.add("bet");
list.add("bear");
list.add("beat");
list.add("become");
list.add("begin");

List<String> matches = list.stream().filter(it -> it.contains("bea")).collect(Collectors.toList());

System.out.println(matches); // [bear, beat]

And even easier in Kotlin:

val matches = list.filter { it.contains("bea") }

ajax jquery simple get request

var dataString = "flag=fetchmediaaudio&id="+id;

$.ajax
({
  type: "POST",
  url: "ajax.php",
  data: dataString,
  success: function(html)
  {
     alert(html);
  }
});

SQL Server: Is it possible to insert into two tables at the same time?

If you want the actions to be more or less atomic, I would make sure to wrap them in a transaction. That way you can be sure both happened or both didn't happen as needed.

Windows Forms ProgressBar: Easiest way to start/stop marquee?

It's not how they work. You "start" a marquee style progress bar by making it visible, you stop it by hiding it. You could change the Style property.

matplotlib colorbar for scatter

From the matplotlib docs on scatter 1:

cmap is only used if c is an array of floats

So colorlist needs to be a list of floats rather than a list of tuples as you have it now. plt.colorbar() wants a mappable object, like the CircleCollection that plt.scatter() returns. vmin and vmax can then control the limits of your colorbar. Things outside vmin/vmax get the colors of the endpoints.

How does this work for you?

import matplotlib.pyplot as plt
cm = plt.cm.get_cmap('RdYlBu')
xy = range(20)
z = xy
sc = plt.scatter(xy, xy, c=z, vmin=0, vmax=20, s=35, cmap=cm)
plt.colorbar(sc)
plt.show()

Image Example

How to drop SQL default constraint without knowing its name?

Run this command to browse all constraints:

exec sp_helpconstraint 'mytable' --and look under constraint_name. 

It will look something like this: DF__Mytable__Column__[ABC123]. Then you can just drop the constraint.

How do I manually configure a DataSource in Java?

use MYSQL as Example: 1) use database connection pools: for Example: Apache Commons DBCP , also, you need basicDataSource jar package in your classpath

@Bean
public BasicDataSource dataSource() {
    BasicDataSource ds = new BasicDataSource();
    ds.setDriverClassName("com.mysql.jdbc.Driver");
    ds.setUrl("jdbc:mysql://localhost:3306/gene");
    ds.setUsername("root");
    ds.setPassword("root");
    return ds;
}

2)use JDBC-based Driver it is usually used if you don't consider connection pool:

@Bean
public DataSource dataSource(){
    DriverManagerDataSource ds = new DriverManagerDataSource();
    ds.setDriverClassName("com.mysql.jdbc.Driver");
    ds.setUrl("jdbc:mysql://localhost:3306/gene");
    ds.setUsername("root");
    ds.setPassword("root");
    return ds;
}

Get the height and width of the browser viewport without scrollbars using jquery?

$(document).ready(function() {

  //calculate the window height & add css properties for height 100%

  wh = $( window ).height();

  ww = $( window ).width();

  $(".targeted-div").css({"height": wh, "width": ww});

});

Text vertical alignment in WPF TextBlock

If you can overlook the height of TextBlock, it's better for you to use this:

<TextBlock Height="{Binding}" Text="Your text"
TextWrapping="Wrap" VerticalAlignment="Center" Width="28"/>

How to render an ASP.NET MVC view as a string?

Here is a class I wrote to do this for ASP.NETCore RC2. I use it so I can generate html email using Razor.

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.Abstractions;
using Microsoft.AspNetCore.Mvc.ModelBinding;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.AspNetCore.Mvc.ViewEngines;
using Microsoft.AspNetCore.Mvc.ViewFeatures;
using Microsoft.AspNetCore.Routing;
using System.IO;
using System.Threading.Tasks;

namespace cloudscribe.Web.Common.Razor
{
    /// <summary>
    /// the goal of this class is to provide an easy way to produce an html string using 
    /// Razor templates and models, for use in generating html email.
    /// </summary>
    public class ViewRenderer
    {
        public ViewRenderer(
            ICompositeViewEngine viewEngine,
            ITempDataProvider tempDataProvider,
            IHttpContextAccessor contextAccesor)
        {
            this.viewEngine = viewEngine;
            this.tempDataProvider = tempDataProvider;
            this.contextAccesor = contextAccesor;
        }

        private ICompositeViewEngine viewEngine;
        private ITempDataProvider tempDataProvider;
        private IHttpContextAccessor contextAccesor;

        public async Task<string> RenderViewAsString<TModel>(string viewName, TModel model)
        {

            var viewData = new ViewDataDictionary<TModel>(
                        metadataProvider: new EmptyModelMetadataProvider(),
                        modelState: new ModelStateDictionary())
            {
                Model = model
            };

            var actionContext = new ActionContext(contextAccesor.HttpContext, new RouteData(), new ActionDescriptor());
            var tempData = new TempDataDictionary(contextAccesor.HttpContext, tempDataProvider);

            using (StringWriter output = new StringWriter())
            {

                ViewEngineResult viewResult = viewEngine.FindView(actionContext, viewName, true);

                ViewContext viewContext = new ViewContext(
                    actionContext,
                    viewResult.View,
                    viewData,
                    tempData,
                    output,
                    new HtmlHelperOptions()
                );

                await viewResult.View.RenderAsync(viewContext);

                return output.GetStringBuilder().ToString();
            }
        }
    }
}

jQuery $.cookie is not a function

Here are all the possible problems/solutions I have come across:

1. Download the cookie plugin

$.cookie is not a standard jQuery function and the plugin needs to be downloaded here. Make sure to include the appropriate <script> tag where necessary (see next).

2. Include jQuery before the cookie plugin

When including the cookie script, make sure to include jQuery FIRST, then the cookie plugin.

<script src="~/Scripts/jquery-2.0.3.js" type="text/javascript"></script>
<script src="~/Scripts/jquery_cookie.js" type="text/javascript"></script>

3. Don't include jQuery more than once

This was my problem. Make sure you aren't including jQuery more than once. If you are, it is possible that:

  1. jQuery loads correctly.
  2. The cookie plugin loads correctly.
  3. Your second inclusion of jQuery overwrites the first and destroys the cookie plugin.

For anyone using ASP.Net MVC projects, be careful with the default javascript bundle inclusions. My second inclusion of jQuery was within one of my global layout pages under the line @Scripts.Render("~/bundles/jquery").

4. Rename the plugin file to not include ".cookie"

In some rare cases, renaming the file to something that does NOT include ".cookie" has fixed this error, apparently due to web server issues. By default, the downloaded script is titled "jquery.cookie.js" but try renaming it to something like "jquery_cookie.js" as shown above. More details on this problem are here.

Any way to clear python's IDLE window?

This works for me in Windows:

print chr(12)

How to use dashes in HTML-5 data-* attributes in ASP.NET MVC

It's even easier than everything suggested above. Data attributes in MVC which include dashes (-) are catered for with the use of underscore (_).

<%= Html.ActionLink("« Previous", "Search",
 new { keyword = Model.Keyword, page = Model.currPage - 1},
 new { @class = "prev", data_details = "Some Details"   })%>

I see JohnnyO already mentioned this.

Disable password authentication for SSH

Here's a script to do this automatically

# Only allow key based logins
sed -n 'H;${x;s/\#PasswordAuthentication yes/PasswordAuthentication no/;p;}' /etc/ssh/sshd_config > tmp_sshd_config
cat tmp_sshd_config > /etc/ssh/sshd_config
rm tmp_sshd_config

What IDE to use for Python?

Results

Spreadsheet version

spreadsheet screenshot

Alternatively, in plain text: (also available as a a screenshot)

                         Bracket Matching -.  .- Line Numbering
                          Smart Indent -.  |  |  .- UML Editing / Viewing
         Source Control Integration -.  |  |  |  |  .- Code Folding
                    Error Markup -.  |  |  |  |  |  |  .- Code Templates
  Integrated Python Debugging -.  |  |  |  |  |  |  |  |  .- Unit Testing
    Multi-Language Support -.  |  |  |  |  |  |  |  |  |  |  .- GUI Designer (Qt, Eric, etc)
   Auto Code Completion -.  |  |  |  |  |  |  |  |  |  |  |  |  .- Integrated DB Support
     Commercial/Free -.  |  |  |  |  |  |  |  |  |  |  |  |  |  |  .- Refactoring
   Cross Platform -.  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |     
                  +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
Atom              |Y |F |Y |Y*|Y |Y |Y |Y |Y |Y |  |Y |Y |  |  |  |  |*many plugins
Editra            |Y |F |Y |Y |  |  |Y |Y |Y |Y |  |Y |  |  |  |  |  |
Emacs             |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |  |  |  |
Eric Ide          |Y |F |Y |  |Y |Y |  |Y |  |Y |  |Y |  |Y |  |  |  |
Geany             |Y |F |Y*|Y |  |  |  |Y |Y |Y |  |Y |  |  |  |  |  |*very limited
Gedit             |Y |F |Y¹|Y |  |  |  |Y |Y |Y |  |  |Y²|  |  |  |  |¹with plugin; ²sort of
Idle              |Y |F |Y |  |Y |  |  |Y |Y |  |  |  |  |  |  |  |  |
IntelliJ          |Y |CF|Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |
JEdit             |Y |F |  |Y |  |  |  |  |Y |Y |  |Y |  |  |  |  |  |
KDevelop          |Y |F |Y*|Y |  |  |Y |Y |Y |Y |  |Y |  |  |  |  |  |*no type inference
Komodo            |Y |CF|Y |Y |Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |Y |  |
NetBeans*         |Y |F |Y |Y |Y |  |Y |Y |Y |Y |Y |Y |Y |Y |  |  |Y |*pre-v7.0
Notepad++         |W |F |Y |Y |  |Y*|Y*|Y*|Y |Y |  |Y |Y*|  |  |  |  |*with plugin
Pfaide            |W |C |Y |Y |  |  |  |Y |Y |Y |  |Y |Y |  |  |  |  |
PIDA              |LW|F |Y |Y |  |  |  |Y |Y |Y |  |Y |  |  |  |  |  |VIM based
PTVS              |W |F |Y |Y |Y |Y |Y |Y |Y |Y |  |Y |  |  |Y*|  |Y |*WPF bsed
PyCharm           |Y |CF|Y |Y*|Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |*JavaScript
PyDev (Eclipse)   |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |Y |  |  |  |
PyScripter        |W |F |Y |  |Y |Y |  |Y |Y |Y |  |Y |Y |Y |  |  |  |
PythonWin         |W |F |Y |  |Y |  |  |Y |Y |  |  |Y |  |  |  |  |  |
SciTE             |Y |F¹|  |Y |  |Y |  |Y |Y |Y |  |Y |Y |  |  |  |  |¹Mac version is
ScriptDev         |W |C |Y |Y |Y |Y |  |Y |Y |Y |  |Y |Y |  |  |  |  |    commercial
Spyder            |Y |F |Y |  |Y |Y |  |Y |Y |Y |  |  |  |  |  |  |  |
Sublime Text      |Y |CF|Y |Y |  |Y |Y |Y |Y |Y |  |Y |Y |Y*|  |  |  |extensible w/Python,
TextMate          |M |F |  |Y |  |  |Y |Y |Y |Y |  |Y |Y |  |  |  |  |    *PythonTestRunner
UliPad            |Y |F |Y |Y |Y |  |  |Y |Y |  |  |  |Y |Y |  |  |  |
Vim               |Y |F |Y |Y |Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |  |  |
Visual Studio     |W |CF|Y |Y |Y |Y |Y |Y |Y |Y |? |Y |? |? |Y |? |Y |
Visual Studio Code|Y |F |Y |Y |Y |Y |Y |Y |Y |Y |? |Y |? |? |? |? |Y |uses plugins
WingIde           |Y |C |Y |Y*|Y |Y |Y |Y |Y |Y |  |Y |Y |Y |  |  |  |*support for C
Zeus              |W |C |  |  |  |  |Y |Y |Y |Y |  |Y |Y |  |  |  |  |
                  +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+
   Cross Platform -'  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |     
     Commercial/Free -'  |  |  |  |  |  |  |  |  |  |  |  |  |  |  '- Refactoring
   Auto Code Completion -'  |  |  |  |  |  |  |  |  |  |  |  |  '- Integrated DB Support
    Multi-Language Support -'  |  |  |  |  |  |  |  |  |  |  '- GUI Designer (Qt, Eric, etc)
  Integrated Python Debugging -'  |  |  |  |  |  |  |  |  '- Unit Testing
                    Error Markup -'  |  |  |  |  |  |  '- Code Templates
         Source Control Integration -'  |  |  |  |  '- Code Folding
                          Smart Indent -'  |  |  '- UML Editing / Viewing
                         Bracket Matching -'  '- Line Numbering

Acronyms used:

 L  - Linux
 W  - Windows
 M  - Mac
 C  - Commercial
 F  - Free
 CF - Commercial with Free limited edition
 ?  - To be confirmed

I don't mention basics like syntax highlighting as I expect these by default.


This is a just dry list reflecting your feedback and comments, I am not advocating any of these tools. I will keep updating this list as you keep posting your answers.

PS. Can you help me to add features of the above editors to the list (like auto-complete, debugging, etc.)?

We have a comprehensive wiki page for this question https://wiki.python.org/moin/IntegratedDevelopmentEnvironments

Submit edits to the spreadsheet

Multiple -and -or in PowerShell Where-Object statement

By wrapping your comparisons in {} in your first example you are creating ScriptBlocks; so the PowerShell interpreter views it as Where-Object { <ScriptBlock> -and <ScriptBlock> }. Since the -and operator operates on boolean values, PowerShell casts the ScriptBlocks to boolean values. In PowerShell anything that is not empty, zero or null is true. The statement then looks like Where-Object { $true -and $true } which is always true.

Instead of using {}, use parentheses ().

Also you want to use -eq instead of -match since match uses regex and will be true if the pattern is found anywhere in the string (try: 'xlsx' -match 'xls').

Invoke-Command -computername SERVERNAME { 
    Get-ChildItem -path E:\dfsroots\datastore2\public | 
        Where-Object {($_.extension -eq ".xls" -or $_.extension -eq ".xlk") -and ($_.creationtime -ge "06/01/2014")}
}

A better option is to filter the extensions at the Get-ChildItem command.

Invoke-Command -computername SERVERNAME { 
    Get-ChildItem -path E:\dfsroots\datastore2\public\* -Include *.xls, *.xlk | 
        Where-Object {$_.creationtime -ge "06/01/2014"}
}

Incrementing a date in JavaScript

var myDate = new Date();

//add a day to the date
myDate.setDate(myDate.getDate() + 1);

PHP executable not found. Install PHP 7 and add it to your PATH or set the php.executablePath setting

You installed PHP IntelliSense extension, and this error because of it.
So if you want to fix this problem go to this menu:
File -> Preferences -> Settings
Now you can see 2 window. In the right window add below codes:

{
    "php.validate.executablePath": "C:\\wamp64\\bin\\php\\php7.0.4\\php.exe",
    "php.executablePath": "C:\\wamp64\\bin\\php\\php7.0.4\\php.exe"
}

Just like below image.

enter image description here

NOTICE: This address C:\\wamp64\\bin\\php\\php7.0.4\\php.exe is my php7.exe file address. Replace this address with own php7.exe.

Change Color of Fonts in DIV (CSS)

To do links, you can do

.social h2 a:link {
  color: pink;
  font-size: 14px;   
}

You can change the hover, visited, and active link styling too. Just replace "link" with what you want to style. You can learn more at the w3schools page CSS Links.

get list of packages installed in Anaconda

in terminal, type : conda list to obtain the packages installed using conda.

for the packages that pip recognizes, type : pip list

There may be some overlap of these lists as pip may recognize packages installed by conda (but maybe not the other way around, IDK).

There is a useful source here, including how to update or upgrade packages..

JQuery/Javascript: check if var exists

I suspect there are many answers like this on SO but here you go:

if ( typeof pagetype !== 'undefined' && pagetype == 'textpage' ) {
  ...
}

What's the difference between JavaScript and Java?

They have nothing to do with each other.

Java is statically typed, compiles, runs on its own VM.

Javascript is dynamically typed, interpreted, and runs in a browser. It also has first-class functions and anonymous functions, which Java does not. It has direct access to web-page elements, which makes it useful for doing client-side processing.

They are also somewhat similar in syntax, but that's about it.

Changing specific text's color using NSMutableAttributedString in Swift

This extension works well when configuring the text of a label with an already set default color.

public extension String {
    func setColor(_ color: UIColor, ofSubstring substring: String) -> NSMutableAttributedString {
        let range = (self as NSString).range(of: substring)
        let attributedString = NSMutableAttributedString(string: self)
        attributedString.addAttribute(NSAttributedString.Key.foregroundColor, value: color, range: range)
        return attributedString
    }
}

For example

let text = "Hello World!"
let attributedText = text.setColor(.blue, ofSubstring: "World")

let myLabel = UILabel()
myLabel.textColor = .white
myLabel.attributedText = attributedText

pip install: Please check the permissions and owner of that directory

What is the problem here is that you somehow installed into virtualenv using sudo. Probably by accident. This means root user will rewrite Python package data, making all file owned by root and your normal user cannot write those files anymore. Usually virtualenv should be used and owned by your normal UNIX user only.

You can fix the issue by changing UNIX file permissions pack to your user. Try:

$ sudo chown -R USERNAME /Users/USERNAME/Library/Logs/pip
$ sudo chown -R USERNAME /Users/USERNAME/Library/Caches/pip

then pip should be able to write those files again.

More information about UNIX file permission management

Prevent screen rotation on Android

User "portrait" in your AndroidManifest.xml file might seem like a good solution. But it forces certain devices (that work best in landscape) to go into portrait, not getting the proper orientation. On the latest Android version, you will get wearing an error. So my suggestion it's better to use "nosensor".

<activity
        ...
        ...
        android:screenOrientation="nosensor">

Angular ng-if not true

use this

ng-if="area == false"

OR

ng-if="area == true"

this may help someone

Typedef function pointer?

typedef is a language construct that associates a name to a type.
You use it the same way you would use the original type, for instance

  typedef int myinteger;
  typedef char *mystring;
  typedef void (*myfunc)();

using them like

  myinteger i;   // is equivalent to    int i;
  mystring s;    // is the same as      char *s;
  myfunc f;      // compile equally as  void (*f)();

As you can see, you could just replace the typedefed name with its definition given above.

The difficulty lies in the pointer to functions syntax and readability in C and C++, and the typedef can improve the readability of such declarations. However, the syntax is appropriate, since functions - unlike other simpler types - may have a return value and parameters, thus the sometimes lengthy and complex declaration of a pointer to function.

The readability may start to be really tricky with pointers to functions arrays, and some other even more indirect flavors.

To answer your three questions

  • Why is typedef used? To ease the reading of the code - especially for pointers to functions, or structure names.

  • The syntax looks odd (in the pointer to function declaration) That syntax is not obvious to read, at least when beginning. Using a typedef declaration instead eases the reading

  • Is a function pointer created to store the memory address of a function? Yes, a function pointer stores the address of a function. This has nothing to do with the typedef construct which only ease the writing/reading of a program ; the compiler just expands the typedef definition before compiling the actual code.

Example:

typedef int (*t_somefunc)(int,int);

int product(int u, int v) {
  return u*v;
}

t_somefunc afunc = &product;
...
int x2 = (*afunc)(123, 456); // call product() to calculate 123*456

How to get on scroll events?

You could use a @HostListener decorator. Works with Angular 4 and up.

import { HostListener } from '@angular/core';

@HostListener("window:scroll", []) onWindowScroll() {
    // do some stuff here when the window is scrolled
    const verticalOffset = window.pageYOffset 
          || document.documentElement.scrollTop 
          || document.body.scrollTop || 0;
}

Broadcast Receiver within a Service

as your service is already setup, simply add a broadcast receiver in your service:

private final BroadcastReceiver receiver = new BroadcastReceiver() {
   @Override
   public void onReceive(Context context, Intent intent) {
      String action = intent.getAction();
      if(action.equals("android.provider.Telephony.SMS_RECEIVED")){
        //action for sms received
      }
      else if(action.equals(android.telephony.TelephonyManager.ACTION_PHONE_STATE_CHANGED)){
           //action for phone state changed
      }     
   }
};

in your service's onCreate do this:

IntentFilter filter = new IntentFilter();
filter.addAction("android.provider.Telephony.SMS_RECEIVED");
filter.addAction(android.telephony.TelephonyManager.ACTION_PHONE_STATE_CHANGED);
filter.addAction("your_action_strings"); //further more
filter.addAction("your_action_strings"); //further more

registerReceiver(receiver, filter);

and in your service's onDestroy:

unregisterReceiver(receiver);

and you are good to go to receive broadcast for what ever filters you mention in onCreate. Make sure to add any permission if required. for e.g.

<uses-permission android:name="android.permission.RECEIVE_SMS" />

How to close TCP and UDP ports via windows command line

Use TCPView: http://technet.microsoft.com/en-us/sysinternals/bb897437.aspx
or CurrPorts: https://www.nirsoft.net/utils/cports.html

Alternatively, if you don't want to use EXTERNAL SOFTWARE (these tools don't require an installation by the way), you can simply FIRST run the netstat command (preferably netstat -b ) & then setup Local Security Policy to block the IP address of the user's machine in question, that's what I have been doing with unwanted or even unknown connections - that allows you doing everything WITHOUT ANY EXTERNAL SOFTWARE (everything comes with Windows)...

C# LINQ find duplicates in List

there is an answer but i did not understand why is not working;

var anyDuplicate = enumerable.GroupBy(x => x.Key).Any(g => g.Count() > 1);

my solution is like that in this situation;

var duplicates = model.list
                    .GroupBy(s => s.SAME_ID)
                    .Where(g => g.Count() > 1).Count() > 0;
if(duplicates) {
    doSomething();
}

NodeJS: How to decode base64 encoded string back to binary?

As of Node.js v6.0.0 using the constructor method has been deprecated and the following method should instead be used to construct a new buffer from a base64 encoded string:

var b64string = /* whatever */;
var buf = Buffer.from(b64string, 'base64'); // Ta-da

For Node.js v5.11.1 and below

Construct a new Buffer and pass 'base64' as the second argument:

var b64string = /* whatever */;
var buf = new Buffer(b64string, 'base64'); // Ta-da

If you want to be clean, you can check whether from exists :

if (typeof Buffer.from === "function") {
    // Node 5.10+
    buf = Buffer.from(b64string, 'base64'); // Ta-da
} else {
    // older Node versions, now deprecated
    buf = new Buffer(b64string, 'base64'); // Ta-da
}

How to run a PowerShell script from a batch file

You need the -ExecutionPolicy parameter:

Powershell.exe -executionpolicy remotesigned -File  C:\Users\SE\Desktop\ps.ps1

Otherwise PowerShell considers the arguments a line to execute and while Set-ExecutionPolicy is a cmdlet, it has no -File parameter.

What throws an IOException in Java?

Java documentation is helpful to know the root cause of a particular IOException.

Just have a look at the direct known sub-interfaces of IOException from the documentation page:

ChangedCharSetException, CharacterCodingException, CharConversionException, ClosedChannelException, EOFException, FileLockInterruptionException, FileNotFoundException, FilerException, FileSystemException, HttpRetryException, IIOException, InterruptedByTimeoutException, InterruptedIOException, InvalidPropertiesFormatException, JMXProviderException, JMXServerErrorException, MalformedURLException, ObjectStreamException, ProtocolException, RemoteException, SaslException, SocketException, SSLException, SyncFailedException, UnknownHostException, UnknownServiceException, UnsupportedDataTypeException, UnsupportedEncodingException, UserPrincipalNotFoundException, UTFDataFormatException, ZipException

Most of these exceptions are self-explanatory.

A few IOExceptions with root causes:

EOFException: Signals that an end of file or end of stream has been reached unexpectedly during input. This exception is mainly used by data input streams to signal the end of the stream.

SocketException: Thrown to indicate that there is an error creating or accessing a Socket.

RemoteException: A RemoteException is the common superclass for a number of communication-related exceptions that may occur during the execution of a remote method call. Each method of a remote interface, an interface that extends java.rmi.Remote, must list RemoteException in its throws clause.

UnknownHostException: Thrown to indicate that the IP address of a host could not be determined (you may not be connected to Internet).

MalformedURLException: Thrown to indicate that a malformed URL has occurred. Either no legal protocol could be found in a specification string or the string could not be parsed.

How to get a microtime in Node.js?

Get hrtime as single number in one line:

const begin = process.hrtime();
// ... Do the thing you want to measure
const nanoSeconds = process.hrtime(begin).reduce((sec, nano) => sec * 1e9 + nano)

Array.reduce, when given a single argument, will use the array's first element as the initial accumulator value. One could use 0 as the initial value and this would work as well, but why do the extra * 0.

Bootstrap select dropdown list placeholder

Try @title = "stuff". It worked for me.

How to enable assembly bind failure logging (Fusion) in .NET

I wrote an assembly binding log viewer named Fusion++ and put it on GitHub.

You can get the latest release from here or via chocolatey (choco install fusionplusplus).

I hope you and some of the visitors in here can save some worthy lifetime minutes with it.

Fusion++

Reload a DIV without reloading the whole page

try this

<script type="text/javascript">
window.onload = function(){


var auto_refresh = setInterval(
function ()
{
$('.View').html('');
$('.View').load('Small.php').fadeIn("slow");
}, 15000); // refresh every 15000 milliseconds

}
</script>

Mongoose: Get full list of users

To make function to wait for list to be fetched.

getArrayOfData() {
    return DataModel.find({}).then(function (storedDataArray) {
        return storedDataArray;
    }).catch(function(err){
        if (err) {
            throw new Error(err.message);
        }
    });
}

Get Line Number of certain phrase in file Python

Here's what I've found to work:

f_rd = open(path, 'r')
file_lines = f_rd.readlines()
f_rd.close()

matches = [line for line in file_lines if "chars of Interest" in line]
index = file_lines.index(matches[0])

Calculate average in java

If you're trying to get the integers from the command line args, you'll need something like this:

public static void main(String[] args) {
    int[] nums = new int[args.length];
    for(int i = 0; i < args.length; i++) {
        try {
            nums[i] = Integer.parseInt(args[i]);
        }
        catch(NumberFormatException nfe) {
            System.err.println("Invalid argument");
        }
    }

    // averaging code here
}

As for the actual averaging code, others have suggested how you can tweak that (so I won't repeat what they've said).

Edit: actually it's probably better to just put it inside the above loop and not use the nums array at all

Fastest Way of Inserting in Entity Framework

Configuration.LazyLoadingEnabled = false; Configuration.ProxyCreationEnabled = false;

these are too effect to speed without AutoDetectChangesEnabled = false; and i advise to use different table header from dbo. generally i use like nop,sop,tbl etc..

iptables LOG and DROP in one rule

Although already over a year old, I stumbled across this question a couple of times on other Google search and I believe I can improve on the previous answer for the benefit of others.

Short answer is you cannot combine both action in one line, but you can create a chain that does what you want and then call it in a one liner.

Let's create a chain to log and accept:

iptables -N LOG_ACCEPT

And let's populate its rules:

iptables -A LOG_ACCEPT -j LOG --log-prefix "INPUT:ACCEPT:" --log-level 6
iptables -A LOG_ACCEPT -j ACCEPT

Now let's create a chain to log and drop:

iptables -N LOG_DROP

And let's populate its rules:

iptables -A LOG_DROP -j LOG --log-prefix "INPUT:DROP: " --log-level 6
iptables -A LOG_DROP -j DROP

Now you can do all actions in one go by jumping (-j) to you custom chains instead of the default LOG / ACCEPT / REJECT / DROP:

iptables -A <your_chain_here> <your_conditions_here> -j LOG_ACCEPT
iptables -A <your_chain_here> <your_conditions_here> -j LOG_DROP

$(document).on("click"... not working?

This works:

<div id="start-element">Click Me</div>

$(document).on("click","#test-element",function() {
    alert("click");
});

$(document).on("click","#start-element",function() {
    $(this).attr("id", "test-element");
});

Here is the Fiddle

php: catch exception and continue execution, is it possible?

Sure:

try {
   throw new Exception('Something bad');
} catch (Exception $e) {
    // Do nothing
}

You might want to go have a read of the PHP documentation on Exceptions.

Escaping Double Quotes in Batch Script

If the string is already within quotes then use another quote to nullify its action.

echo "Insert tablename(col1) Values('""val1""')" 

Creating a left-arrow button (like UINavigationBar's "back" style) on a UIToolbar

If you want to avoid drawing it yourself, you could use the undocumented class: UINavigationButton with style 1. This could, of course, stop your application from being approved... /John

How to get the full path of the file from a file input

You cannot do so - the browser will not allow this because of security concerns. Although there are workarounds, the fact is that you shouldn't count on this working. The following Stack Overflow questions are relevant here:

In addition to these, the new HTML5 specification states that browsers will need to feed a Windows compatible fakepath into the input type="file" field, ostensibly for backward compatibility reasons.

So trying to obtain the path is worse then useless in newer browsers - you'll actually get a fake one instead.

gcc: undefined reference to

However, avpicture_get_size is defined.

No, as the header (<libavcodec/avcodec.h>) just declares it.

The definition is in the library itself.

So you might like to add the linker option to link libavcodec when invoking gcc:

-lavcodec

Please also note that libraries need to be specified on the command line after the files needing them:

gcc -I$HOME/ffmpeg/include program.c -lavcodec

Not like this:

gcc -lavcodec -I$HOME/ffmpeg/include program.c

Referring to Wyzard's comment, the complete command might look like this:

gcc -I$HOME/ffmpeg/include program.c -L$HOME/ffmpeg/lib -lavcodec

For libraries not stored in the linkers standard location the option -L specifies an additional search path to lookup libraries specified using the -l option, that is libavcodec.x.y.z in this case.


For a detailed reference on GCC's linker option, please read here.

Event when window.location.href changes

popstate event:

The popstate event is fired when the active history entry changes. [...] The popstate event is only triggered by doing a browser action such as a click on the back button (or calling history.back() in JavaScript)

So, listening to popstate event and sending a popstate event when using history.pushState() should be enough to take action on href change:

window.addEventListener('popstate', listener);

const pushUrl = (href) => {
  history.pushState({}, '', href);
  window.dispatchEvent(new Event('popstate'));
};

Uncompress tar.gz file

Use -C option of tar:

tar zxvf <yourfile>.tar.gz -C /usr/src/

and then, the content of the tar should be in:

/usr/src/<yourfile>

How to change Android version and code version number?

Go in the build.gradle and set the version code and name inside the defaultConfig element

defaultConfig {
    minSdkVersion 9
    targetSdkVersion 19
    versionCode 1
    versionName "1.0"
}

screenshot

Inserting one list into another list in java?

100, it will hold the same references. Therefore if you make a change to a specific object in the list, it will affect the same object in anotherList.

Adding or removing objects in any of the list will not affect the other.

list and anotherList are two different instances, they only hold the same references of the objects "inside" them.

Create intermediate folders if one doesn't exist

You have to actually call some method to create the directories. Just creating a file object will not create the corresponding file or directory on the file system.

You can use File#mkdirs() method to create the directory: -

theFile.mkdirs();

Difference between File#mkdir() and File#mkdirs() is that, the later will create any intermediate directory if it does not exist.

C# Return Different Types?

My post here is strictly related to Blazor v5 but should work in 3.x as well. Additionally, I'm using these methods with bootstrap 4.5 and 5.0 beta 1 but you could easily adapt it to use style's instead of classes or use your own classes.

To those recommending dynamic, I thank you. The dynamic type seems like it can be very valuable when used correctly. Most of the time you'll probably use an interface but this wasn't plausible for me. I went ahead and updated my project with a dynamic return type and it's working great while being the quickest, cleanest solution.

I previously added the following extension methods to boolean types to help me avoid long ternary operators in razor page code. Here are the 3 main extension methods I use to accomplish it:

public static T Then<T>(this bool value, T result) => value ? result : default;    
public static T Then<T>(this bool value, T thenResult, T elseResult) => value ? thenResult : elseResult;
public static T Else<T>(this bool value, T result) => !value ? result : default;

The following are examples of that implementation:

<div class="@Hidden.Then("d-none")">
    Hidden content...
</div>

Note: ErrorOrWarning would hide the content if there was no error/warning so I could default it to yellow/italic but this is an example so please use your imagination:

<div class="@ErrorOrWarning.Else("d-none")" style="@Error.Then("color:red;font-weight:bold;","color:yellow;font-style:italic;")">
    Error/Warning content...
</div>

This is the typical implementation without the extension methods. It's common to see this technique in Blazor guides/tutorials/videos online. There are cleaner ways to handle it but this is the basic idea:

<div class="@(ErrorOrWarning ? "" : "d-none")" style="@(Error ? "color:red;font-weight:bold;" : "color:yellow;font-style:italic;")">
    Error/Warning content...
</div>

While this might not seem like too big a difference, if you have a lot of dynamic content/styles driving your page, it can get really messy. With those 3 lines of code you can enhance the readability and cleanliness and it really does reduce risk of typos. Adding two more extension methods, you can reduce the risk even further Note: Again, this is using bootstrap class "d-none" for the style "display:none!important" but you could just as easily replace with your own usage:

public static string ThenShow(this bool value) => value ? "" : "d-none";
public static string ThenHide(this bool value) => value ? "d-none" : "";

The limitation I previously faced was when using the overloaded Then(thenResult, elseResult), each of the parameters must be of the same type. 99% of the time this is fine. Actually, another 0.5% of the time it's still okay because you can probably solve it quickly with a .ToString() or an explicit cast.

What I ran into, and what took me to this post was: I have a control you can imagine as a button. There is an Enum property allowing the user to select an icon to display. The selected Enum dynamically populates a readonly MarkupString property. As an alternative option, they can use the ChildContent (or IconContent in my example) of type RenderFragment. This will let them manually add anything they want (maybe an iFrame to stackoverflow haha) but my intention is for them to add style, most likely in the form of an icon.

I know I can cast/convert one to the other however my existing extension method is so clean and simple, it would be great to be able to use pass the MarkupString and RenderFragment together as parameters, conditionally output to the razor page. So, thanks to this post, I changed my Then(thenResult, elseResult) extension methods to use unique generic parameter types and return a dynamic type like so:

public static dynamic Then<T,E>(this bool value, T thenResult, E elseResult) => value ? thenResult : elseResult;

Now in my razor page I have a very simple line for the icon output. Note: IconContent is a RenderFragment and IconMarkup is a MarkupString.

@((@IconContent == null).Then(IconMarkup, IconContent))

And because I love extension methods and I'm typing this up, I took it a step further with another extension method:

public static bool IsNull(this RenderFragment value) => value == null;

Which enables the extremely clean and simple:

@IconContent.IsNull().Then(IconMarkup, IconContent)

Here's the extra extension method I mentioned above which converts a string to a MarkupString. It might be overkill but I like it.

public static MarkupString ToMarkup(this string value) => (MarkupString)value;

Let me know if you have a better recommendation or if you think I'm doing something wrong. I'm sure this post makes it seem like I overuse extension methods but I really don't. I keep their use limited to outcomes such as I've outlined in this post.

Extract a substring using PowerShell

Not sure if this is efficient or not, but strings in PowerShell can be referred to using array index syntax, in a similar fashion to Python.

It's not completely intuitive because of the fact the first letter is referred to by index = 0, but it does:

  • Allow a second index number that is longer than the string, without generating an error
  • Extract substrings in reverse
  • Extract substrings from the end of the string

Here are some examples:

PS > 'Hello World'[0..2]

Yields the result (index values included for clarity - not generated in output):

H [0]
e [1]
l [2]

Which can be made more useful by passing -join '':

PS > 'Hello World'[0..2] -join ''
Hel

There are some interesting effects you can obtain by using different indices:

Forwards

Use a first index value that is less than the second and the substring will be extracted in the forwards direction as you would expect. This time the second index value is far in excess of the string length but there is no error:

PS > 'Hello World'[3..300] -join ''
lo World

Unlike:

PS > 'Hello World'.Substring(3,300)
Exception calling "Substring" with "2" argument(s): "Index and length must refer to a location within
the string.

Backwards

If you supply a second index value that is lower than the first, the string is returned in reverse:

PS > 'Hello World'[4..0] -join ''
olleH

From End

If you use negative numbers you can refer to a position from the end of the string. To extract 'World', the last 5 letters, we use:

PS > 'Hello World'[-5..-1] -join ''
World

Should each and every table have a primary key?

Short answer: yes.

Long answer:

  • You need your table to be joinable on something
  • If you want your table to be clustered, you need some kind of a primary key.
  • If your table design does not need a primary key, rethink your design: most probably, you are missing something. Why keep identical records?

In MySQL, the InnoDB storage engine always creates a primary key if you didn't specify it explicitly, thus making an extra column you don't have access to.

Note that a primary key can be composite.

If you have a many-to-many link table, you create the primary key on all fields involved in the link. Thus you ensure that you don't have two or more records describing one link.

Besides the logical consistency issues, most RDBMS engines will benefit from including these fields in a unique index.

And since any primary key involves creating a unique index, you should declare it and get both logical consistency and performance.

See this article in my blog for why you should always create a unique index on unique data:

P.S. There are some very, very special cases where you don't need a primary key.

Mostly they include log tables which don't have any indexes for performance reasons.

How to sort 2 dimensional array by column value?

Using the arrow function, and sorting by the second string field

_x000D_
_x000D_
var a = [[12, 'CCC'], [58, 'AAA'], [57, 'DDD'], [28, 'CCC'],[18, 'BBB']];_x000D_
a.sort((a, b) => a[1].localeCompare(b[1]));_x000D_
console.log(a)
_x000D_
_x000D_
_x000D_

Entity Framework Refresh context?

yourContext.Entry(yourEntity).Reload();

Display the current date and time using HTML and Javascript with scrollable effects in hta application

Try this one:

HTML:

<div id="para1"></div>

JavaScript:

document.getElementById("para1").innerHTML = formatAMPM();

function formatAMPM() {
var d = new Date(),
    minutes = d.getMinutes().toString().length == 1 ? '0'+d.getMinutes() : d.getMinutes(),
    hours = d.getHours().toString().length == 1 ? '0'+d.getHours() : d.getHours(),
    ampm = d.getHours() >= 12 ? 'pm' : 'am',
    months = ['Jan','Feb','Mar','Apr','May','Jun','Jul','Aug','Sep','Oct','Nov','Dec'],
    days = ['Sun','Mon','Tue','Wed','Thu','Fri','Sat'];
return days[d.getDay()]+' '+months[d.getMonth()]+' '+d.getDate()+' '+d.getFullYear()+' '+hours+':'+minutes+ampm;
}

Result:

Mon Sep 18 2017 12:40pm

How to Rotate a UIImage 90 degrees?

Simple. Just change the image orientation flag.

UIImage *oldImage = [UIImage imageNamed:@"whatever.jpg"];
UIImageOrientation newOrientation;
switch (oldImage.imageOrientation) {
    case UIImageOrientationUp:
        newOrientation = UIImageOrientationLandscapeLeft;
        break;
    case UIImageOrientationLandscapeLeft:
        newOrientation = UIImageOrientationDown;
        break;
    case UIImageOrientationDown:
        newOrientation = UIImageOrientationLandscapeRight;
        break;
    case UIImageOrientationLandscapeRight:
        newOrientation = UIImageOrientationUp;
        break;
    // you can also handle mirrored orientations similarly ...
}
UIImage *rotatedImage = [UIImage imageWithCGImage:oldImage.CGImage scale:1.0f orientation:newOrientation];

How to make HTML element resizable using pure Javascript?

what about a pure css3 solution?

div {
    resize: both;
    overflow: auto;
} 

MDN Web Docs

W3Schools example

Browser support

Find a string by searching all tables in SQL Server Management Studio 2008

This was very helpful. I wanted to import this function to a Postgre SQL database. Thought i would share it with anyone who is interested. Will have them a few hours. Note: this function creates a list of SQL statements that can be copied and executed on the Postgre database. Maybe someone smarter then me can get Postgre to create and execute the statements all in one function.

CREATE OR REPLACE FUNCTION SearchAllTables(_search text) RETURNS TABLE( txt text ) as $funct$
    DECLARE __COUNT int;
    __SQL text;
BEGIN
    EXECUTE 'SELECT COUNT(0) FROM INFORMATION_SCHEMA.COLUMNS
                    WHERE    DATA_TYPE = ''text'' 
                    AND          table_schema = ''public'' ' INTO __COUNT;

    RETURN QUERY 
        SELECT CASE WHEN ROW_NUMBER() OVER (ORDER BY table_name) < __COUNT THEN 
            'SELECT ''' || table_name ||'.'|| column_name || ''' AS tbl, "'  || column_name || '" AS col FROM "public"."' || "table_name" || '" WHERE "'|| "column_name" || '" ILIKE ''%' || _search  || '%'' UNION ALL' 
            ELSE 
            'SELECT ''' || table_name ||'.'|| column_name || ''' AS tbl, "'  || column_name || '" AS col FROM "public"."' || "table_name" || '" WHERE "'|| "column_name" || '" ILIKE ''%' || _search  || '%'''
        END AS txt

                    FROM     INFORMATION_SCHEMA.COLUMNS
                    WHERE    DATA_TYPE = 'text' 
                    AND          table_schema = 'public';
END
$funct$ LANGUAGE plpgsql;

What is a None value?

Other answers have already explained meaning of None beautifully. However, I would still like to throw more light on this using an example.

Example:

def extendList(val, list=[]):
    list.append(val)
    return list

list1 = extendList(10)
list2 = extendList(123,[])
list3 = extendList('a')

print "list1 = %s" % list1
print "list2 = %s" % list2
print "list3 = %s" % list3

Now try to guess output of above list. Well, the answer is surprisingly as below:

list1 = [10, 'a']
list2 = [123]
list3 = [10, 'a']

But Why?

Many will mistakenly expect list1 to be equal to [10] and list3 to be equal to ['a'], thinking that the list argument will be set to its default value of [] each time extendList is called.

However, what actually happens is that the new default list is created only once when the function is defined, and that same list is then used subsequently whenever extendList is invoked without a list argument being specified. This is because expressions in default arguments are calculated when the function is defined, not when it’s called.

list1 and list3 are therefore operating on the same default list, whereas list2 is operating on a separate list that it created (by passing its own empty list as the value for the list parameter).


'None' the savior: (Modify example above to produce desired behavior)

def extendList(val, list=None):
    if list is None:
       list = []
    list.append(val)
    return list

list1 = extendList(10)
list2 = extendList(123,[])
list3 = extendList('a')

print "list1 = %s" % list1
print "list2 = %s" % list2
print "list3 = %s" % list3

With this revised implementation, the output would be:

list1 = [10]
list2 = [123]
list3 = ['a']

Note - Example credit to toptal.com

Check if a string has white space

Here is my suggested validation:

var isValid = false;

// Check whether this entered value is numeric.
function checkNumeric() {
    var numericVal = document.getElementById("txt_numeric").value;

    if(isNaN(numericVal) || numericVal == "" || numericVal == null || numericVal.indexOf(' ') >= 0) {
        alert("Please, enter a numeric value!");
        isValid = false;
    } else {
        isValid = true;
    }
}

jquery UI dialog: how to initialize without a title bar?

I like overriding jQuery widgets.

(function ($) {
    $.widget("sauti.dialog", $.ui.dialog, {
        options: {
            headerVisible: false
        },
        _create: function () {
            // ready to generate button
            this._super("_create"); // for 18 would be $.Widget.prototype._create.call(this);
            // decide if header is visible
            if(this.options.headerVisible == false)
                this.uiDialogTitlebar.hide();
        },
        _setOption: function (key, value) {
            this._super(key, value); // for 1.8 would be $.Widget.prototype._setOption.apply( this, arguments );
            if (key === "headerVisible") {
                if (key == false)
                    this.uiDialogTitlebar.hide();
                else
                    this.uiDialogTitlebar.show();
                return;
            }
        }
    });
})(jQuery);

So you can now setup if you want to show title bar or not

   $('#mydialog').dialog({
      headerVisible: false // or true
});

Access HTTP response as string in Go

bs := string(body) should be enough to give you a string.

From there, you can use it as a regular string.

A bit as in this thread:

var client http.Client
resp, err := client.Get(url)
if err != nil {
    log.Fatal(err)
}
defer resp.Body.Close()

if resp.StatusCode == http.StatusOK {
    bodyBytes, err := ioutil.ReadAll(resp.Body)
    if err != nil {
        log.Fatal(err)
    }
    bodyString := string(bodyBytes)
    log.Info(bodyString)
}

See also GoByExample.

As commented below (and in zzn's answer), this is a conversion (see spec).
See "How expensive is []byte(string)?" (reverse problem, but the same conclusion apply) where zzzz mentioned:

Some conversions are the same as a cast, like uint(myIntvar), which just reinterprets the bits in place.

Sonia adds:

Making a string out of a byte slice, definitely involves allocating the string on the heap. The immutability property forces this.
Sometimes you can optimize by doing as much work as possible with []byte and then creating a string at the end. The bytes.Buffer type is often useful.

window.location.href doesn't redirect

Make sure you're not sending a '#' at the end of your URL. In my case, that was preventing window.location.href from working.

Powershell: count members of a AD group

$users = Get-ADGroupMember -Identity 'Client Services' -Recursive ; $users.count

The above one-liner gives a clean count of recursive members found. Simple, easy, and one line.

How to convert Seconds to HH:MM:SS using T-SQL

DECLARE @seconds AS int = 896434;
SELECT
    CONVERT(varchar, (@seconds / 86400))                --Days
    + ':' +
    CONVERT(varchar, DATEADD(ss, @seconds, 0), 108);    --Hours, Minutes, Seconds

Outputs:

10:09:00:34

How to make a node.js application run permanently?

I'd recommend looking for something such as Forever to restart Node in the event of a crash, and handle daemonizing this for you.

Where am I? - Get country

I used GEOIP db and created a function. You can consume this link directly http://jamhubsoftware.com/geoip/getcountry.php

{"country":["India"],"isoCode":["IN"],"names":[{"de":"Indien","en":"India","es":"India","fr":"Inde","ja":"\u30a4\u30f3\u30c9","pt-BR":"\u00cdndia","ru":"\u0418\u043d\u0434\u0438\u044f","zh-CN":"\u5370\u5ea6"}]}

you can download autoload.php and .mmdb file from https://dev.maxmind.com/geoip/geoip2/geolite2/

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
$ip_address = $_SERVER['REMOTE_ADDR'];
//$ip_address = '3.255.255.255';

require_once 'vendor/autoload.php';

use GeoIp2\Database\Reader;

// This creates the Reader object, which should be reused across
// lookups.
$reader = new Reader('/var/www/html/geoip/GeoLite2-City.mmdb');

// Replace "city" with the appropriate method for your database, e.g.,
// "country".
$record = $reader->city($ip_address);

//print($record->country->isoCode . "\n"); // 'US'
//print($record->country->name . "\n"); // 'United States'
$rows['country'][] = $record->country->name;
$rows['isoCode'][] = $record->country->isoCode;
$rows['names'][] = $record->country->names;
print json_encode($rows);
//print($record->country->names['zh-CN'] . "\n"); // '??'
//
//print($record->mostSpecificSubdivision->name . "\n"); // 'Minnesota'
//print($record->mostSpecificSubdivision->isoCode . "\n"); // 'MN'
//
//print($record->city->name . "\n"); // 'Minneapolis'
//
//print($record->postal->code . "\n"); // '55455'
//
//print($record->location->latitude . "\n"); // 44.9733
//print($record->location->longitude . "\n"); // -93.2323
?>

How to recursively delete an entire directory with PowerShell 2.0?

To delete the complete contents including the folder structure use

get-childitem $dest -recurse | foreach ($_) {remove-item $_.fullname -recurse}

The -recurse added to remove-item ensures interactive prompts are disabled.

GSON throwing "Expected BEGIN_OBJECT but was BEGIN_ARRAY"?

I am not sure if this is the best way to use GSON, but works for me. You can use some like this on the MainActivity:

 public void readJson() {
    dataArrayList = new ArrayList<>();
    String json = "[\n" + IOHelper.getData(this) + "\n]\n";
    Log.d(TAG, json);
    try{
        JSONArray channelSearchEnums = new JSONArray(json);

        for(int i=0; i< channelSearchEnums.length(); i++)
        {
            JSONObject enum = channelSearchEnums.getJSONObject(i);
            ChannelSearchEnum channel = new ChannelSearchEnum(
                   enum.getString("updated_at"), enum.getString("fetched_at"),
                   enum.getString("description"), enum.getString("language"),
                   enum.getString("title"), enum.getString("url"),
                   enum.getString("icon_url"), enum.getString("logo_url"),
                   enum.getString("id"), enum.getString("modified"))         

                   dataArrayList.add(channel);
        }

         //The code and place you want to show your data            

    }catch (Exception e)
    {
        Log.d(TAG, e.getLocalizedMessage());
    }
}

You only have strings, but if you would have doubles or int, you could put getDouble or getInt too.

The method of IOHelper class is the next (Here, the path is save on the internal Storage):

 public static String getData(Context context) {
    try {
        File f = new File(context.getFilesDir().getPath() + "/" + fileName);
        //check whether file exists
        FileInputStream is = new FileInputStream(f);
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        return new String(buffer);
    } catch (IOException e) {
        Log.e("TAG", "Error in Reading: " + e.getLocalizedMessage());
        return null;
    }
}

If you want more information about this, you can see this video, where I get the code of readJson(); and this thread where I get the code of getData().

How do I check if an object has a key in JavaScript?

You should use hasOwnProperty. For example:

myObj.hasOwnProperty('myKey');

Note: If you are using ESLint, the above may give you an error for violating the no-prototype-builtins rule, in that case the workaround is as below:

Object.prototype.hasOwnProperty.call(myObj, 'myKey');

How to change the sender's name or e-mail address in mutt?

One special case for this is if you have used a construction like the following in your ~/.muttrc:

# Reset From email to default
send-hook . "my_hdr From: Real Name <[email protected]>"

This send-hook will override either of these:

mutt -e "set [email protected]"
mutt -e "my_hdr From: Other Name <[email protected]>"

Your emails will still go out with the header:

From: Real Name <[email protected]>

In this case, the only command line solution I've found is actually overriding the send-hook itself:

mutt -e "send-hook . \"my_hdr From: Other Name <[email protected]>\""

what is difference between success and .done() method of $.ajax

In short, decoupling success callback function from the ajax function so later you can add your own handlers without modifying the original code (observer pattern).

Please find more detailed information from here: https://stackoverflow.com/a/14754681/1049184

Can an abstract class have a constructor?

Yes surely you can add one, as already mentioned for initialization of Abstract class variables. BUT if you dont explicitly declare one, it anyways has an implicit constructor for "Constructor Chaining" to work.

Angular routerLink does not navigate to the corresponding component

For not very sharp eyes like mine, I had href instead of routerLink, took me a few searches to figure that out #facepalm.

Comparing arrays for equality in C++

Right. In most, if not all implementations of C, the array identifier can be implicitly casted to a pointer to the first element (i.e. the first element's address). What you're doing here is comparing those addresses, which is obviously wrong.

Instead, you need to iterate over both arrays, checking each element against each other. If you get to the end of both without a failure, they're equal.

Responsive background image in div full width

I also tried this style for ionic hybrid app background. this is also having style for background blur effect.

.bg-image {
   position: absolute;
   background: url(../img/bglogin.jpg) no-repeat;
   height: 100%;
   width: 100%;
   background-size: cover;
   bottom: 0px;
   margin: 0 auto;
   background-position: 50%;


  -webkit-filter: blur(5px);
  -moz-filter: blur(5px);
  -o-filter: blur(5px);
  -ms-filter: blur(5px);
  filter: blur(5px);

}

How can I get the ID of an element using jQuery?

Important: if you are creating a new object with jQuery and binding an event, you MUST use prop and not attr, like this:

$("<div/>",{ id: "yourId", class: "yourClass", html: "<span></span>" }).on("click", function(e) { alert($(this).prop("id")); }).appendTo("#something");

Getting the text that follows after the regex match

You just need to put "group(1)" instead of "group()" in the following line and the return will be the one you expected:

System.out.println("I found the text: " + matcher.group(**1**).toString());

C++ unordered_map using a custom class type as the key

I think, jogojapan gave an very good and exhaustive answer. You definitively should take a look at it before reading my post. However, I'd like to add the following:

  1. You can define a comparison function for an unordered_map separately, instead of using the equality comparison operator (operator==). This might be helpful, for example, if you want to use the latter for comparing all members of two Node objects to each other, but only some specific members as key of an unordered_map.
  2. You can also use lambda expressions instead of defining the hash and comparison functions.

All in all, for your Node class, the code could be written as follows:

using h = std::hash<int>;
auto hash = [](const Node& n){return ((17 * 31 + h()(n.a)) * 31 + h()(n.b)) * 31 + h()(n.c);};
auto equal = [](const Node& l, const Node& r){return l.a == r.a && l.b == r.b && l.c == r.c;};
std::unordered_map<Node, int, decltype(hash), decltype(equal)> m(8, hash, equal);

Notes:

  • I just reused the hashing method at the end of jogojapan's answer, but you can find the idea for a more general solution here (if you don't want to use Boost).
  • My code is maybe a bit too minified. For a slightly more readable version, please see this code on Ideone.

Enter key press behaves like a Tab in Javascript

$("#form input , select , textarea").keypress(function(e){
    if(e.keyCode == 13){
        var enter_position = $(this).index();
        $("#form input , select , textarea").eq(enter_position+1).focus();
    }
});

javax.net.ssl.SSLException: Read error: ssl=0x9524b800: I/O error during system call, Connection reset by peer

Android Supports SSL implementation by default except for Android N (API level 24) and below Android 5.1 (API level 22)
I was getting the error when making the API call below API level 22 devices after implementing SSL at the server side; that was while creating OkHttpClient client object, and fixed by adding connectionSpecs() method OkHttpClient.Builder class.

the error received was

response failure: javax.net.ssl.SSLException: SSL handshake aborted: ssl=0xb8882c00: I/O error during system call, Connection reset by peer

so I fixed this by added the check like

if ( Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP_MR1) {
            // Do something for below api level 22
            List<ConnectionSpec> specsList = getSpecsBelowLollipopMR1(okb);
            if (specsList != null) {
                okb.connectionSpecs(specsList);
            }
        }

Also for the Android N (API level 24); I was getting the error while making the HTTP call like

HTTP FAILED: javax.net.ssl.SSLHandshakeException: Handshake failed

and this is fixed by adding the check for Android 7 particularly, like

if (android.os.Build.VERSION.SDK_INT == Build.VERSION_CODES.N){
            // Do something for naugat ; 7
            okb.connectionSpecs(Collections.singletonList(getSpec()));
        }

So my final OkHttpClient object will be like:

         OkHttpClient client
         HttpLoggingInterceptor httpLoggingInterceptor2 = new
         HttpLoggingInterceptor();
         httpLoggingInterceptor2.setLevel(HttpLoggingInterceptor.Level.BODY);

         OkHttpClient.Builder okb = new OkHttpClient.Builder()
                 .addInterceptor(httpLoggingInterceptor2)
               .addInterceptor(new Interceptor() {
                     @Override
                     public Response intercept(Chain chain) throws IOException {
                         Request request = chain.request();
                         Request request2 = request.newBuilder().addHeader(AUTH_KEYWORD, AUTH_TYPE_JW + " " + password).build();
                         return chain.proceed(request2);
                     }
                 }).connectTimeout(30, TimeUnit.SECONDS)
                 .writeTimeout(30, TimeUnit.SECONDS)
                 .readTimeout(30, TimeUnit.SECONDS);

         if (android.os.Build.VERSION.SDK_INT == Build.VERSION_CODES.N){
             // Do something for naugat ; 7
             okb.connectionSpecs(Collections.singletonList(getSpec()));
         }

         if ( Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP_MR1) {
             List<ConnectionSpec> specsList = getSpecsBelowLollipopMR1(okb);
             if (specsList != null) {
                 okb.connectionSpecs(specsList);
             }
         }

         //init client
         client = okb.build();

getSpecsBelowLollipopMR1 function be like,

   private List<ConnectionSpec> getSpecsBelowLollipopMR1(OkHttpClient.Builder okb) {

        try {

            SSLContext sc = SSLContext.getInstance("TLSv1.2");
            sc.init(null, null, null);
            okb.sslSocketFactory(new Tls12SocketFactory(sc.getSocketFactory()));

            ConnectionSpec cs = new ConnectionSpec.Builder(ConnectionSpec.MODERN_TLS)
                    .tlsVersions(TlsVersion.TLS_1_2)
                    .build();

            List<ConnectionSpec> specs = new ArrayList<>();
            specs.add(cs);
            specs.add(ConnectionSpec.COMPATIBLE_TLS);

            return specs;

        } catch (Exception exc) {
            Timber.e("OkHttpTLSCompat Error while setting TLS 1.2"+ exc);

            return null;
        }
    }

The Tls12SocketFactory class will be found in below link (comment by gotev):

https://github.com/square/okhttp/issues/2372


For more support adding some links below this will help you in detail,

https://developer.android.com/training/articles/security-ssl

D/OkHttp: <-- HTTP FAILED: javax.net.ssl.SSLException: SSL handshake aborted: ssl=0x64e3c938: I/O error during system call, Connection reset by peer

How to restore/reset npm configuration to default values?

If it's about just one property - let's say you want to temporarily change some default, for instance disable CA checking: you can do it with

npm config set ca ""

To come back to the defaults for that setting, simply

npm config delete ca

To verify, use npm config get ca.

How to run a command as a specific user in an init script?

I usually do it the way that you are doing it (i.e. sudo -u username command). But, there is also the 'djb' way to run a daemon with privileges of another user. See: http://thedjbway.b0llix.net/daemontools/uidgid.html

prevent iphone default keyboard when focusing an <input>

So here is my solution (similar to John Vance's answer):

First go here and get a function to detect mobile browsers.

http://detectmobilebrowsers.com/

They have a lot of different ways to detect if you are on mobile, so find one that works with what you are using.

Your HTML page (pseudo code):

If Mobile Then
    <input id="selling-date" type="date" placeholder="YYYY-MM-DD" max="2999-12-31" min="2010-01-01" value="2015-01-01" />
else
    <input id="selling-date" type="text" class="date-picker" readonly="readonly" placeholder="YYYY-MM-DD" max="2999-12-31" min="2010-01-01" value="2015-01-01" />

JQuery:

$( ".date-picker" ).each(function() {
    var min = $( this ).attr("min");
    var max = $( this ).attr("max");
    $( this ).datepicker({ 
        dateFormat: "yy-mm-dd",  
        minDate: min,  
        maxDate: max  
    });
});

This way you can still use native date selectors in mobile while still setting the min and max dates either way.

The field for non mobile should be read only because if a mobile browser like chrome for ios "requests desktop version" then they can get around the mobile check and you still want to prevent the keyboard from showing up.

However if the field is read only it could look to a user like they cant change the field. You could fix this by changing the CSS to make it look like it isn't read only (ie change border-color to black) but unless you are changing the CSS for all input tags you will find it hard to keep the look consistent across browsers.

To get arround that I just add a calendar image button to the date picker. Just change your JQuery code a bit:

$( ".date-picker" ).each(function() {
    var min = $( this ).attr("min");
    var max = $( this ).attr("max");
    $( this ).datepicker({ 
        dateFormat: "yy-mm-dd",  
        minDate: min,  
        maxDate: max,
        showOn: "both",
        buttonImage: "images/calendar.gif",
        buttonImageOnly: true,
        buttonText: "Select date"
    });
});

Note: you will have to find a suitable image.

Make EditText ReadOnly

android:editable

If set, specifies that this TextView has an input method. It will be a textual one unless it has otherwise been specified. For TextView, this is false by default. For EditText, it is true by default.

Must be a boolean value, either true or false.

This may also be a reference to a resource (in the form @[package:]type:name) or theme attribute (in the form ?[package:][type:]name) containing a value of this type.

This corresponds to the global attribute resource symbol editable.

Related Methods

Display a loading bar before the entire page is loaded

I've recently made a page loader in vanilla .js for a project, just wanted to share it as all the other answers are jQuery based. It's a plug and play, one-liner.

It automatically creates a <div> tag prepended to the <body>, with a <svg> loader. If you want to customize the color you just have to update the t variable at the beginning of the script.

var t="#106CF6",u=document.querySelector("*"),s=document.createElement("style"),a=document.createElement("aside"),m="http://www.w3.org/2000/svg",g=document.createElementNS(m,"svg"),c=document.createElementNS(m,"circle");document.head.appendChild(s),(s.innerHTML="#sailor {background:"+t+";color:"+t+";display:flex;align-items:center;justify-content:center;position:fixed;top:0;height:100vh;width:100vw;z-index:2147483647}@keyframes swell{to{transform:rotate(360deg)}}#sailor svg{animation:.3s swell infinite linear}"),a.setAttribute("id","sailor"),document.body.prepend(a),g.setAttribute("height","50"),g.setAttribute("filter","brightness(175%)"),g.setAttribute("viewBox","0 0 100 100"),a.prepend(g),c.setAttribute("cx","50"),c.setAttribute("cy","50"),c.setAttribute("r","35"),c.setAttribute("fill","none"),c.setAttribute("stroke","currentColor"),c.setAttribute("stroke-dasharray","165 57"),c.setAttribute("stroke-width","10"),g.prepend(c),(u.style.pointerEvents="none"),(u.style.userSelect="none"),(u.style.cursor="wait"),window.addEventListener("load",function(){setTimeout(function(){(u.style.pointerEvents=""),(u.style.userSelect=""),(u.style.cursor="");a.remove()},100)})

You can see the full project and documentation on the GitHub

What is console.log in jQuery?

jQuery and console.log are unrelated entities, although useful when used together.

If you use a browser's built-in dev tools, console.log will log information about the object being passed to the log function.

If the console is not active, logging will not work, and may break your script. Be certain to check that the console exists before logging:

if (window.console) console.log('foo');

The shortcut form of this might be seen instead:

window.console&&console.log('foo');

There are other useful debugging functions as well, such as debug, dir and error. Firebug's wiki lists the available functions in the console api.

jQuery form validation on button click

$(document).ready(function() {
    $("#form1").validate({
        rules: {
            field1: "required"
        },
        messages: {
            field1: "Please specify your name"
        }
    })
});

<form id="form1" name="form1">
     Field 1: <input id="field1" type="text" class="required">
    <input id="btn" type="submit" value="Validate">
</form>

You are also you using type="button". And I'm not sure why you ought to separate the submit button, place it within the form. It's more proper to do it that way. This should work.

How can I completely uninstall nodejs, npm and node in Ubuntu

I was crazy to delete node and npm and nodejs from my Ubuntu 14.04 but with this steps you will remove it:

sudo apt-get uninstall nodejs npm node
sudo apt-get remove nodejs npm node

If you uninstall correctly and it is still there, check these links:

You can also try using find:

find / -name "node"

Although since that is likely to take a long time and return a lot of confusing false positives, you may want to search only PATH locations:

find $(echo $PATH | sed 's/:/ /g') -name "node"

It would probably be in /usr/bin/node or /usr/local/bin. After finding it, you can delete it using the correct path, eg:

sudo rm /usr/bin/node

"E: Unable to locate package python-pip" on Ubuntu 18.04

Try following command sequence on Ubuntu terminal:

sudo apt-get install software-properties-common
sudo apt-add-repository universe
sudo apt-get update
sudo apt-get install python-pip

Java: Simplest way to get last word in a string

String testString = "This is a sentence";
String[] parts = testString.split(" ");
String lastWord = parts[parts.length - 1];
System.out.println(lastWord); // "sentence"

How to support UTF-8 encoding in Eclipse

Just right click the Project -- Properties and select Resource on the left side menu.

You can now change the Text-file encoding to whatever you wish.

How can I validate google reCAPTCHA v2 using javascript/jQuery?

I thought all of them were great but I had troubles actually getting them to work with javascript and c#. Here is what I did. Hope it helps someone else.

//put this at the top of the page
<script src="https://www.google.com/recaptcha/api.js"></script>

//put this under the script tag
<script>
var isCaptchaValid = false;
function doCaptchaValidate(source, args) {
    args.IsValid = isCaptchaValid;
}
var verifyCallback = function (response) {
    isCaptchaValid = true;
};
</script>

//retrieved from google and added callback
<div class="g-recaptcha" data-sitekey="sitekey" data-callback="verifyCallback">

//created a custom validator and added error message and ClientValidationFucntion
<asp:CustomValidator runat="server" ID="CustomValidator1" ValidationGroup="Initial" ErrorMessage="Captcha Required" ClientValidationFunction="doCaptchaValidate"/>

How do you auto format code in Visual Studio?

You can also try right menu click option to format the selection of the coding document. Take a look at below screen shot

enter image description here

How to check if a radiobutton is checked in a radiogroup in Android?

  rgrp.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(RadioGroup radioGroup, int i) {
            switch(i) {
                case R.id.type_car:
                    num=1;
                    Toast.makeText(getApplicationContext()," Car",Toast.LENGTH_LONG).show();
                    break;
                case R.id.type_bike:
                    num=2;
                    Toast.makeText(getApplicationContext()," Bike",Toast.LENGTH_LONG).show();
                    break;
            }
        }
    });

Adjust UILabel height depending on the text

Finally, it worked. Thank you guys.

I was not getting it to work because i was trying to resize the label in heightForRowAtIndexPath method:

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

and (yeah silly me), i was resizing the label to default in cellForRowAtIndexPath method - i was overlooking the code i had written earlier:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath

Unable to establish SSL connection, how do I fix my SSL cert?

The problem I faced was in client server environment. The client was trying to connect over http port 80 but wanted the server proxy to redirect the request to some other port and data was https. So basically asking secure information over http. So server should have http port 80 as well as the port client is requesting, let's say urla:1111\subB.

The issue was server was hosting this on some other port e,g urla:2222\subB; so the client was trying to access over 1111 was receiving the error. Correcting the port number should fix this issue. In this case to port number 1111.

Select only rows if its value in a particular column is less than the value in the other column

If you use dplyr package you can do:

library(dplyr)
filter(df, aged <= laclen)

Javascript array sort and unique

Here is a simple one liner with O(N), no complicated loops necessary.

> Object.keys(['a', 'b', 'a'].reduce((l, r) => l[r] = l, {})).sort()
[ 'a', 'b' ]

Explanation

Original data set, assume its coming in from an external function

const data = ['a', 'b', 'a']

We want to group all the values onto an object as keys as the method of deduplication. So we use reduce with an object as the default value:

[].reduce(fn, {})

The next step is to create a reduce function which will put the values in the array onto the object. The end result is an object with a unique set of keys.

const reduced = data.reduce((l, r) => l[r] = l, {})

We set l[r] = l because in javascript the value of the assignment expression is returned when an assignment statement is used as an expression. l is the accumulator object and r is the key value. You can also use Object.assign(l, { [r]: (l[r] || 0) + 1 }) or something similar to get the count of each value if that was important to you.

Next we want to get the keys of that object

const keys = Object.keys(reduced)

Then simply use the built-in sort

console.log(keys.sort())

Which is the set of unique values of the original array, sorted

['a', 'b']

Joining Spark dataframes on the key

Alias Approach using scala (this is example given for older version of spark for spark 2.x see my other answer) :

You can use case class to prepare sample dataset ... which is optional for ex: you can get DataFrame from hiveContext.sql as well..

import org.apache.spark.sql.functions.col

case class Person(name: String, age: Int, personid : Int)

case class Profile(name: String, personid  : Int , profileDescription: String)

    val df1 = sqlContext.createDataFrame(
   Person("Bindu",20,  2) 
:: Person("Raphel",25, 5) 
:: Person("Ram",40, 9):: Nil)


val df2 = sqlContext.createDataFrame(
Profile("Spark",2,  "SparkSQLMaster") 
:: Profile("Spark",5, "SparkGuru") 
:: Profile("Spark",9, "DevHunter"):: Nil
)

// you can do alias to refer column name with aliases to  increase readablity

val df_asPerson = df1.as("dfperson")
val df_asProfile = df2.as("dfprofile")


val joined_df = df_asPerson.join(
    df_asProfile
, col("dfperson.personid") === col("dfprofile.personid")
, "inner")


joined_df.select(
  col("dfperson.name")
, col("dfperson.age")
, col("dfprofile.name")
, col("dfprofile.profileDescription"))
.show

sample Temp table approach which I don't like personally...

The reason to use the registerTempTable( tableName ) method for a DataFrame, is so that in addition to being able to use the Spark-provided methods of a DataFrame, you can also issue SQL queries via the sqlContext.sql( sqlQuery ) method, that use that DataFrame as an SQL table. The tableName parameter specifies the table name to use for that DataFrame in the SQL queries.

df_asPerson.registerTempTable("dfperson");
df_asProfile.registerTempTable("dfprofile")

sqlContext.sql("""SELECT dfperson.name, dfperson.age, dfprofile.profileDescription
                  FROM  dfperson JOIN  dfprofile
                  ON dfperson.personid == dfprofile.personid""")

If you want to know more about joins pls see this nice post : beyond-traditional-join-with-apache-spark

enter image description here

Note : 1) As mentioned by @RaphaelRoth ,

val resultDf = PersonDf.join(ProfileDf,Seq("personId")) is good approach since it doesnt have duplicate columns from both sides if you are using inner join with same table.
2) Spark 2.x example updated in another answer with full set of join operations supported by spark 2.x with examples + result

TIP :

Also, important thing in joins : broadcast function can help to give hint please see my answer

Is it possible to specify proxy credentials in your web.config?

You can specify credentials by adding a new Generic Credential of your proxy server in Windows Credentials Manager:

1 In Web.config

<system.net>    
<defaultProxy enabled="true" useDefaultCredentials="true">      
<proxy usesystemdefault="True" />      
</defaultProxy>    
</system.net>
  1. In Credential Manager >> Add a Generic Credential

Internet or network address: your proxy address
User name: your user name
Password: you pass

This configuration worked for me, without change the code.

ImportError: No module named model_selection

Your sklearn version is too low, model_selection is imported by 0.18.1, so please update the sklearn version.

How to add an ORDER BY clause using CodeIgniter's Active Record methods?

I believe the get() function immediately runs the select query and does not accept ORDER BY conditions as parameters. I think you'll need to separately declare the conditions, then run the query. Give this a try:

$this->db->from($this->table_name);
$this->db->order_by("name", "asc");
$query = $this->db->get(); 
return $query->result();

CodeIgniter Documentation order_by()

How to show shadow around the linearlayout in Android?

Actually I agree with @odedbreiner but I put the dialog_frame inside the first layer and hide the black background under the white layer.

    <?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:drawable="@android:drawable/dialog_frame"
        android:right="2dp" android:left="2dp" android:bottom="2dp" android:top="5dp" >
        <shape android:shape="rectangle">
            <corners android:radius="5dp"/>
        </shape>
    </item>
    <item>
        <shape
            android:shape="rectangle">
            <solid android:color="@android:color/white"/>
            <corners android:radius="5dp"/>
        </shape>
    </item>
</layer-list>

Adding a legend to PyPlot in Matplotlib in the simplest manner possible

You can access the Axes instance (ax) with plt.gca(). In this case, you can use

plt.gca().legend()

You can do this either by using the label= keyword in each of your plt.plot() calls or by assigning your labels as a tuple or list within legend, as in this working example:

import numpy as np
import matplotlib.pyplot as plt
x = np.linspace(-0.75,1,100)
y0 = np.exp(2 + 3*x - 7*x**3)
y1 = 7-4*np.sin(4*x)
plt.plot(x,y0,x,y1)
plt.gca().legend(('y0','y1'))
plt.show()

pltGcaLegend

However, if you need to access the Axes instance more that once, I do recommend saving it to the variable ax with

ax = plt.gca()

and then calling ax instead of plt.gca().

Why doesn't java.io.File have a close method?

A BufferedReader can be opened and closed but a File is never opened, it just represents a path in the filesystem.

How do I convert an ANSI encoded file to UTF-8 with Notepad++?

Maybe this is not the answer you needed, but I encountered similar problem, so I decided to put it here.

I needed to convert 500 xml files to UTF8 via Notepad++. Why Notepad++? When I used the option "Encode in UTF8" (many other converters use the same logic) it messed up all special characters, so I had to use "Convert to UTF8" explicitly.


Here some simple steps to convert multiple files via Notepad++ without messing up with special characters (for ex. diacritical marks).

  1. Run Notepad++ and then open menu Plugins->Plugin Manager->Show Plugin Manager
  2. Install Python Script. When plugin is installed, restart the application.
  3. Choose menu Plugins->Python Script->New script.
  4. Choose its name, and then past the following code:

convertToUTF8.py

import os
import sys
from Npp import notepad # import it first!

filePathSrc="C:\\Users\\" # Path to the folder with files to convert
for root, dirs, files in os.walk(filePathSrc):
    for fn in files: 
        if fn[-4:] == '.xml': # Specify type of the files
            notepad.open(root + "\\" + fn)      
            notepad.runMenuCommand("Encoding", "Convert to UTF-8")
            # notepad.save()
            # if you try to save/replace the file, an annoying confirmation window would popup.
            notepad.saveAs("{}{}".format(fn[:-4], '_utf8.xml')) 
            notepad.close()

After all, run the script

What is the easiest way to clear a database from the CLI with manage.py in Django?

Quickest (drops and creates all tables including data):

./manage.py reset appname | ./manage.py dbshell

Caution:

  • Might not work on Windows correctly.
  • Might keep some old tables in the db

jQuery/JavaScript to replace broken images

I got the same problem. This code works well on my case.

// Replace broken images by a default img
$('img').each(function(){
    if($(this).attr('src') === ''){
      this.src = '/default_feature_image.png';
    }
});

SQL join: selecting the last records in a one-to-many relationship

Please try this,

SELECT 
c.Id,
c.name,
(SELECT pi.price FROM purchase pi WHERE pi.Id = MAX(p.Id)) AS [LastPurchasePrice]
FROM customer c INNER JOIN purchase p 
ON c.Id = p.customerId 
GROUP BY c.Id,c.name;

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

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

How to link to specific line number on github

Click the line number, and then copy and paste the link from the address bar. To select a range, click the number, and then shift click the later number.

Alternatively, the links are a relatively simple format, just append #L<number> to the end for that specific line number, using the link to the file. Here's a link to the third line of the git repository's README:

https://github.com/git/git/blob/master/README#L3

Screenshot with highlighted line and the modified address line

How to edit the legend entry of a chart in Excel?

There are 3 ways to do this:

1. Define the Series names directly

Right-click on the Chart and click Select Data then edit the series names directly as shown below.

enter image description here

You can either specify the values directly e.g. Series 1 or specify a range e.g. =A2

enter image description here

2. Create a chart defining upfront the series and axis labels

Simply select your data range (in similar format as I specified) and create a simple bar chart. The labels should be defined automatically. enter image description here

3. Define the legend (series names) using VBA

Similarly you can define the series names dynamically using VBA. A simple example below:

ActiveChart.ChartArea.Select
ActiveChart.FullSeriesCollection(1).Name = "=""Hello"""

This will redefine the first series name. Just change the index from (1) to e.g. (2) and so on to change the following series names. What does the VBA above do? It sets the series name to Hello as "=""Hello""" translates to ="Hello" (" have to be escaped by a preceding ").

"Expected BEGIN_OBJECT but was STRING at line 1 column 1"

I have come to share an solution. The error happened to me after forcing the notbook to hang up. possible solution clean preject.

Scatter plots in Pandas/Pyplot: How to plot by category

It's rather hacky, but you could use one1 as a Float64Index to do everything in one go:

df.set_index('one').sort_index().groupby('key1')['two'].plot(style='--o', legend=True)

enter image description here

Note that as of 0.20.3, sorting the index is necessary, and the legend is a bit wonky.

Understanding repr( ) function in Python

str() is used for creating output for end user while repr() is used for debuggin development.And it's represent the official of object.

Example:

>>> import datetime
>>> today = datetime.datetime.now()
>>> str(today)
'2018-04-08 18:00:15.178404'
>>> repr(today)
'datetime.datetime(2018, 4, 8, 18, 3, 21, 167886)'

From output we see that repr() shows the official representation of date object.

Display / print all rows of a tibble (tbl_df)

The tibble vignette has an updated way to change its default printing behavior:

You can control the default appearance with options:

options(tibble.print_max = n, tibble.print_min = m): if there are more than n rows, print only the first m rows. Use options(tibble.print_max = Inf) to always show all rows.

options(tibble.width = Inf) will always print all columns, regardless of the width of the screen.

examples

This will always print all rows:

options(tibble.print_max = Inf)

This will not actually limit the printing to 50 lines:

options(tibble.print_max = 50)

But this will restrict printing to 50 lines:

options(tibble.print_max = 50, tibble.print_min = 50)

How do I use Spring Boot to serve static content located in Dropbox folder?

Based on @Dave Syers answer I add the following class to my Spring Boot project:

@Configuration
public class StaticResourceConfiguration extends WebMvcConfigurerAdapter {

 private static final Logger LOG = LoggerFactory.getLogger(StaticResourceConfiguration.class);

 @Value("${static.path}")
 private String staticPath;

 @Override
 public void addResourceHandlers(ResourceHandlerRegistry registry) {

    if(staticPath != null) {
        LOG.info("Serving static content from " + staticPath);
        registry.addResourceHandler("/**").addResourceLocations("file:" + staticPath);
    }
 }

 // see https://stackoverflow.com/questions/27381781/java-spring-boot-how-to-map-my-my-app-root-to-index-html
 @Override
 public void addViewControllers(ViewControllerRegistry registry) {
    registry.addViewController("/").setViewName("redirect:/index.html");
 }
}

This allows me to start my spring boot app with the parameter --static.path like

java -jar spring-app-1.0-SNAPSHOT.jar --static.path=/path/to/my/static-files/

This can be very handy for development and testing.

Add and remove a class on click using jQuery?

Why not try something like this?

$('#menu li a').on('click', function(){
    $('#menu li a.current').removeClass('current');
    $(this).addClass('current');
});

JSFiddle

How to sum digits of an integer in java?

The following method will do the task:

public static int sumOfDigits(int n) {
    String digits = new Integer(n).toString();
    int sum = 0;
    for (char c: digits.toCharArray())
        sum += c - '0';
    return sum;
}

You can use it like this:

System.out.printf("Sum of digits = %d%n", sumOfDigits(321));

MySQL and GROUP_CONCAT() maximum length

The short answer: the setting needs to be setup when the connection to the MySQL server is established. For example, if using MYSQLi / PHP, it will look something like this:

$ myConn = mysqli_init(); 
$ myConn->options(MYSQLI_INIT_COMMAND, 'SET SESSION group_concat_max_len = 1000000');

Therefore, if you are using a home-brewed framework, well, you need to look for the place in the code when the connection is establish and provide a sensible value.

I am still using Codeigniter 3 on 2020, so in this framework, the code to add is in the application/system/database/drivers/mysqli/mysqli_driver.php, the function is named db_connect();

public function db_connect($persistent = FALSE)
    {
        // Do we have a socket path?
        if ($this->hostname[0] === '/')
        {
            $hostname = NULL;
            $port = NULL;
            $socket = $this->hostname;
        }
        else
        {
            $hostname = ($persistent === TRUE)
                ? 'p:'.$this->hostname : $this->hostname;
            $port = empty($this->port) ? NULL : $this->port;
            $socket = NULL;
        }

        $client_flags = ($this->compress === TRUE) ? MYSQLI_CLIENT_COMPRESS : 0;
        $this->_mysqli = mysqli_init();

        $this->_mysqli->options(MYSQLI_OPT_CONNECT_TIMEOUT, 10);
        $this->_mysqli->options(MYSQLI_INIT_COMMAND, 'SET SESSION group_concat_max_len = 1000000');

...
    }

Ctrl+click doesn't work in Eclipse Juno

You need to rebuild your workspace using CTRL+B. I a problem where I'd be able to go to the function declarations but for some I wouldn't. After a rebuild, I could do all. I hope that helps.

How to upgrade Angular CLI to the latest version

If you have any difficulties managing your global CLI version it is better to use NVM: MAC, Windows.

To update the local CLI in your Angular project follow this steps:

Starting from CLI v6 you can just run ng update in order to get your dependencies updated automatically to a new version.

ng update @angular/cli

With ng update sometimes you might want to add --force flag.

You can also pass --all flag to upgrade all packages at the same time.

ng update --all --force

If you want just to migrate CLI just run this:

ng update @angular/cli --migrateOnly

You can also pass flag --from=from- version from which to migrate from, e.g --from=1.7.4. This flag is only available with a single package being updated, and only on migration only.

After update is done make sure that the version of typescript you got installed supported by your current angular version, otherwise you might need to downgrade the typescript version. Also bear in mind that usually the latest version of angular won't support the latest version of the typescript.

Checkout Angular CLI / Angular / NodeJS / Typescript compatibility versions here

Also checkout this guide Updating your Angular projects and update.angular.io


OLD ANSWER:
All you need to do is to diff with angular-cli-diff and apply the changes in your current project.

Here is the steps:

  1. Say you go from 1.4. to 1.5 then you do https://github.com/cexbrayat/angular-cli-diff/compare/1.4.0...1.5.0
  2. click on File changed tab
  3. Apply the changes to your current project.
  4. npm install / yarn
  5. Test all npm scripts (more details here: https://stackoverflow.com/a/45431592/415078)

Executing "SELECT ... WHERE ... IN ..." using MySQLdb

args should be tuple.

eg:

args = ('A','B')

args = ('A',) # in case of single

How to display the first few characters of a string in Python?

If you want first 2 letters and last 2 letters of a string then you can use the following code: name = "India" name[0:2]="In" names[-2:]="ia"

How to make a radio button unchecked by clicking it?

If you use Iclick pluging, it is as simply as you see below.

 $('#radio1').iCheck('uncheck');

Can't perform a React state update on an unmounted component

I had this warning possibly because of calling setState from an effect hook (This is discussed in these 3 issues linked together).

Anyway, upgrading the react version removed the warning.

SQL Server SELECT INTO @variable?

You cannot SELECT .. INTO .. a TABLE VARIABLE. The best you can do is create it first, then insert into it. Your 2nd snippet has to be

DECLARE @TempCustomer TABLE
(
   CustomerId uniqueidentifier,
   FirstName nvarchar(100),
   LastName nvarchar(100),
   Email nvarchar(100)
);
INSERT INTO 
    @TempCustomer 
SELECT 
    CustomerId, 
    FirstName, 
    LastName, 
    Email 
FROM 
    Customer
WHERE 
    CustomerId = @CustomerId

How can I create a self-signed cert for localhost?

you could try mkcert.

macos: brew install mkcert

Setting an int to Infinity in C++

int min and max values

Int -2,147,483,648 / 2,147,483,647 Int 64 -9,223,372,036,854,775,808 / 9,223,372,036,854,775,807

i guess you could set a to equal 9,223,372,036,854,775,807 but it would need to be an int64

if you always want a to be grater that b why do you need to check it? just set it to be true always

This table does not contain a unique column. Grid edit, checkbox, Edit, Copy and Delete features are not available

I have been faced with this problem.

The cause is your table doesn't have a primary key field.

And I have a simple solution: Set a field to primary key to specific field that suits your business logic.

For example, I have database thesis_db and field thesis_id, I will press button Primary (key icon) to set thesis_id to become primary key field:

enter image description here

Is there a numpy builtin to reject outliers from a list

Something important when dealing with outliers is that one should try to use estimators as robust as possible. The mean of a distribution will be biased by outliers but e.g. the median will be much less.

Building on eumiro's answer:

def reject_outliers(data, m = 2.):
    d = np.abs(data - np.median(data))
    mdev = np.median(d)
    s = d/mdev if mdev else 0.
    return data[s<m]

Here I have replace the mean with the more robust median and the standard deviation with the median absolute distance to the median. I then scaled the distances by their (again) median value so that m is on a reasonable relative scale.

Note that for the data[s<m] syntax to work, data must be a numpy array.

How to comment out a block of Python code in Vim

There are some good plugins to help comment/uncomment lines. For example The NERD Commenter.

The matching wildcard is strict, but no declaration can be found for element 'tx:annotation-driven'

In my case this was actually a symptom of the server, hosted on AWS, lacking an IP for the external network. It would attempt to download namespaces from springframework.org and fail to make a connection.

Array.push() and unique items

You can use the Set structure from ES6 to make your code faster and more readable:

// Create Set
this.items = new Set();

add(item) {
    this.items.add(item);

    // Set to array
    console.log([...this.items]);
}

How to get city name from latitude and longitude coordinates in Google Maps?

 com.alibaba.fastjson.JSONObject jsonObject = com.alibaba.fastjson.JSONObject.parseObject(data);
        if("OK".equals(jsonObject.getString("status"))){
            String formatted_address;
            JSONArray results = jsonObject.getJSONArray("results");
            if(results != null && results.size() > 0){
                com.alibaba.fastjson.JSONObject object = results.getJSONObject(0);
                String addressComponents = object.getString("address_components");
                formatted_address = object.getString("formatted_address");
                Log.e("amaya","formatted_address="+formatted_address+"--url="+url);
                if(findCity){
                    boolean finded = false;
                    JSONArray ac = JSONArray.parseArray(addressComponents);
                    if(ac != null && ac.size() > 0){
                        for(int i=0;i<ac.size();i++){
                            com.alibaba.fastjson.JSONObject jo = ac.getJSONObject(i);
                            JSONArray types = jo.getJSONArray("types");
                            if(types != null && types.size() > 0){
                                for(int j=0;j<ac.size();j++){
                                    String string = types.getString(i);
                                    if("administrative_area_level_1".equals(string)){
                                        finded = true;
                                        break;
                                    }
                                }
                            }
                            if(finded) break;
                        }
                    }
                    Log.e("amaya","city="+formatted_address);
                }else{
                    Log.e("amaya","poiName="+hotspotPoi.getPoi_name()+"--"+hotspotPoi);
                }
                if(hotspotPoi != null) hotspotPoi.setPoi_name(formatted_address);
                EventBus.getDefault().post(new AmayaEvent.GeoEvent(hotspotPoi));
            }
        }

this is a method to parse google feedback data.

How to use activity indicator view on iPhone?

Create:

spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhiteLarge];
[spinner setCenter:CGPointMake(kScreenWidth/2.0, kScreenHeight/2.0)]; // I do this because I'm in landscape mode
[self.view addSubview:spinner]; // spinner is not visible until started

Start:

[spinner startAnimating]; 

Stop:

 [spinner stopAnimating];

When you're finally done, remove the spinner from the view and release.

How do I mock a REST template exchange?

If anyone is still facing this issue, Captor annotation worked for me

@Captor
private ArgumentCaptor<Object> argumentCaptor;

Then I was able to mock the request by:

ResponseEntity<YourTestResponse> testEntity = new ResponseEntity<>(
    getTestFactoryResponse(), 
    HttpStatus.OK);
when(mockRestTemplate.exchange((String) argumentCaptor.capture(), 
    (HttpMethod) argumentCaptor.capture(), 
    (HttpEntity<?>) argumentCaptor.capture(), 
    (Class<YourTestResponse.class>) any())
).thenReturn(testEntity);

How to detect if a string contains special characters?

SELECT * FROM tableName WHERE columnName LIKE "%#%" OR columnName LIKE "%$%" OR (etc.)

ArrayList initialization equivalent to array initialization

Yes.

new ArrayList<String>(){{
   add("A");
   add("B");
}}

What this is actually doing is creating a class derived from ArrayList<String> (the outer set of braces do this) and then declare a static initialiser (the inner set of braces). This is actually an inner class of the containing class, and so it'll have an implicit this pointer. Not a problem unless you want to serialise it, or you're expecting the outer class to be garbage collected.

I understand that Java 7 will provide additional language constructs to do precisely what you want.

EDIT: recent Java versions provide more usable functions for creating such collections, and are worth investigating over the above (provided at a time prior to these versions)

Max tcp/ip connections on Windows Server 2008

How many thousands of users?

I've run some TCP/IP client/server connection tests in the past on Windows 2003 Server and managed more than 70,000 connections on a reasonably low spec VM. (see here for details: http://www.lenholgate.com/blog/2005/10/the-64000-connection-question.html). I would be extremely surprised if Windows 2008 Server is limited to less than 2003 Server and, IMHO, the posting that Cloud links to is too vague to be much use. This kind of question comes up a lot, I blogged about why I don't really think that it's something that you should actually worry about here: http://www.serverframework.com/asynchronousevents/2010/12/one-million-tcp-connections.html.

Personally I'd test it and see. Even if there is no inherent limit in the Windows 2008 Server version that you intend to use there will still be practical limits based on memory, processor speed and server design.

If you want to run some 'generic' tests you can use my multi-client connection test and the associated echo server. Detailed here: http://www.lenholgate.com/blog/2005/11/windows-tcpip-server-performance.html and here: http://www.lenholgate.com/blog/2005/11/simple-echo-servers.html. These are what I used to run my own tests for my server framework and these are what allowed me to create 70,000 active connections on a Windows 2003 Server VM with 760MB of memory.

Edited to add details from the comment below...

If you're already thinking of multiple servers I'd take the following approach.

  1. Use the free tools that I link to and prove to yourself that you can create a reasonable number of connections onto your target OS (beware of the Windows limits on dynamic ports which may cause your client connections to fail, search for MAX_USER_PORT).

  2. during development regularly test your actual server with test clients that can create connections and actually 'do something' on the server. This will help to prevent you building the server in ways that restrict its scalability. See here: http://www.serverframework.com/asynchronousevents/2010/10/how-to-support-10000-or-more-concurrent-tcp-connections-part-2-perf-tests-from-day-0.html

cd into directory without having permission

I know this post is old, but what i had to do in the case of the above answers on Linux machine was:

sudo chmod +x directory

Installed Java 7 on Mac OS X but Terminal is still using version 6

In case if you have several Java versions on your machine and you want to choose it dynamically at runtime, i.e, in my case, I have two versions:

ls -la /Library/Java/JavaVirtualMachines
drwxr-xr-x  3 root  wheel    96B Nov 16  2014 jdk1.7.0_71.jdk/
drwxr-xr-x  3 root  wheel    96B Mar  1  2015 jdk1.8.0_31.jdk/

You can change them by modifying the /etc/profile content. Just add (or modify) the following two lines at the end of the file:

export JAVA_HOME=YOUR_JAVA_PATH/Contents/Home
export PATH=$JAVA_HOME/bin:$PATH

In my case, it should be like the following if I want to use:

Java 7:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.7.0_71.jdk/Contents/Home
export PATH=$JAVA_HOME/bin:$PATH

Java 8:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_31.jdk/Contents/Home
export PATH=$JAVA_HOME/bin:$PATH

After saving the file, please run source /etc/profile and it should work. Here are results when I use the first and second option accordingly:

Java 7:

java -version
java version "1.7.0_71"
Java(TM) SE Runtime Environment (build 1.7.0_71-b14)

Java 8:

java -version 
java version "1.8.0_31"
Java(TM) SE Runtime Environment (build 1.8.0_31-b13)

The process is similar if your java folder is located in different locations.

Count number of rows matching a criteria

mydata$sCode == "CA" will return a boolean array, with a TRUE value everywhere that the condition is met. To illustrate:

> mydata = data.frame(sCode = c("CA", "CA", "AC"))
> mydata$sCode == "CA"
[1]  TRUE  TRUE FALSE

There are a couple of ways to deal with this:

  1. sum(mydata$sCode == "CA"), as suggested in the comments; because TRUE is interpreted as 1 and FALSE as 0, this should return the numer of TRUE values in your vector.

  2. length(which(mydata$sCode == "CA")); the which() function returns a vector of the indices where the condition is met, the length of which is the count of "CA".

Edit to expand upon what's happening in #2:

> which(mydata$sCode == "CA")
[1] 1 2

which() returns a vector identify each column where the condition is met (in this case, columns 1 and 2 of the dataframe). The length() of this vector is the number of occurences.

Get everything after and before certain character in SQL Server

Inspired by the work of Josien, I wondered about a simplification.

Would this also work? Much shorter:

SELECT SUBSTRING(col, CHARINDEX ('/', col) + 1, CHARINDEX ('.', col) - CHARINDEX ('/', col) - 1);

(I can't test right now because of right issues at my company SQL server, which is a problem in its own right)

T-SQL: Export to new Excel file

This is by far the best post for exporting to excel from SQL:

http://www.sqlteam.com/forums/topic.asp?TOPIC_ID=49926

To quote from user madhivanan,

Apart from using DTS and Export wizard, we can also use this query to export data from SQL Server2000 to Excel

Create an Excel file named testing having the headers same as that of table columns and use these queries

1 Export data to existing EXCEL file from SQL Server table

insert into OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
    'Excel 8.0;Database=D:\testing.xls;', 
    'SELECT * FROM [SheetName$]') select * from SQLServerTable

2 Export data from Excel to new SQL Server table

select * 
into SQLServerTable FROM OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
    'Excel 8.0;Database=D:\testing.xls;HDR=YES', 
    'SELECT * FROM [Sheet1$]')

3 Export data from Excel to existing SQL Server table (edited)

Insert into SQLServerTable Select * FROM OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
    'Excel 8.0;Database=D:\testing.xls;HDR=YES', 
    'SELECT * FROM [SheetName$]')

4 If you dont want to create an EXCEL file in advance and want to export data to it, use

EXEC sp_makewebtask 
    @outputfile = 'd:\testing.xls', 
    @query = 'Select * from Database_name..SQLServerTable', 
    @colheaders =1, 
    @FixedFont=0,@lastupdated=0,@resultstitle='Testing details'

(Now you can find the file with data in tabular format)

5 To export data to new EXCEL file with heading(column names), create the following procedure

create procedure proc_generate_excel_with_columns
(
    @db_name    varchar(100),
    @table_name varchar(100),   
    @file_name  varchar(100)
)
as

--Generate column names as a recordset
declare @columns varchar(8000), @sql varchar(8000), @data_file varchar(100)
select 
    @columns=coalesce(@columns+',','')+column_name+' as '+column_name 
from 
    information_schema.columns
where 
    table_name=@table_name
select @columns=''''''+replace(replace(@columns,' as ',''''' as '),',',',''''')

--Create a dummy file to have actual data
select @data_file=substring(@file_name,1,len(@file_name)-charindex('\',reverse(@file_name)))+'\data_file.xls'

--Generate column names in the passed EXCEL file
set @sql='exec master..xp_cmdshell ''bcp " select * from (select '+@columns+') as t" queryout "'+@file_name+'" -c'''
exec(@sql)

--Generate data in the dummy file
set @sql='exec master..xp_cmdshell ''bcp "select * from '+@db_name+'..'+@table_name+'" queryout "'+@data_file+'" -c'''
exec(@sql)

--Copy dummy file to passed EXCEL file
set @sql= 'exec master..xp_cmdshell ''type '+@data_file+' >> "'+@file_name+'"'''
exec(@sql)

--Delete dummy file 
set @sql= 'exec master..xp_cmdshell ''del '+@data_file+''''
exec(@sql)

After creating the procedure, execute it by supplying database name, table name and file path:

EXEC proc_generate_excel_with_columns 'your dbname', 'your table name','your file path'

Its a whomping 29 pages but that is because others show various other ways as well as people asking questions just like this one on how to do it.

Follow that thread entirely and look at the various questions people have asked and how they are solved. I picked up quite a bit of knowledge just skimming it and have used portions of it to get expected results.

To update single cells

A member also there Peter Larson posts the following: I think one thing is missing here. It is great to be able to Export and Import to Excel files, but how about updating single cells? Or a range of cells?

This is the principle of how you do manage that

update OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=c:\test.xls;hdr=no', 
'SELECT * FROM [Sheet1$b7:b7]') set f1 = -99

You can also add formulas to Excel using this:

update OPENROWSET('Microsoft.Jet.OLEDB.4.0', 
'Excel 8.0;Database=c:\test.xls;hdr=no', 
'SELECT * FROM [Sheet1$b7:b7]') set f1 = '=a7+c7'

Exporting with column names using T-SQL

Member Mladen Prajdic also has a blog entry on how to do this here

References: www.sqlteam.com (btw this is an excellent blog / forum for anyone looking to get more out of SQL Server). For error referencing I used this

Errors that may occur

If you get the following error:

OLE DB provider 'Microsoft.Jet.OLEDB.4.0' cannot be used for distributed queries

Then run this:

sp_configure 'show advanced options', 1;
GO
RECONFIGURE;
GO
sp_configure 'Ad Hoc Distributed Queries', 1;
GO
RECONFIGURE;
GO

In what cases will HTTP_REFERER be empty

HTTP_REFERER - sent by the browser, stating the last page the browser viewed!

If you trusting [HTTP_REFERER] for any reason that is important, you should not, since it can be faked easily:

  1. Some browsers limit access to not allow HTTP_REFERER to be passed
  2. Type a address in the address bar will not pass the HTTP_REFERER
  3. open a new browser window will not pass the HTTP_REFERER, because HTTP_REFERER = NULL
  4. has some browser addon that blocks it for privacy reasons. Some firewalls and AVs do to.

Try this firefox extension, you'll be able to set any headers you want:

@Master of Celebration:

Firefox:

extensions: refspoof, refontrol, modify headers, no-referer

Completely disable: the option is available in about:config under "network.http.sendRefererHeader" and you want to set this to 0 to disable referer passing.

Google chrome / Chromium:

extensions: noref, spoofy, external noreferrer

Completely disable: Chnage ~/.config/google-chrome/Default/Preferences or ~/.config/chromium/Default/Preferences and set this:

{
   ...
   "enable_referrers": false,
   ...
}

Or simply add --no-referrers to shortcut or in cli:

google-chrome --no-referrers

Opera:

Completely disable: Settings > Preferences > Advanced > Network, and uncheck "Send referrer information"

Spoofing web service:

http://referer.us/

Standalone filtering proxy (spoof any header):

Privoxy

Spoofing http_referer when using wget

‘--referer=url’

Spoofing http_referer when using curl

-e, --referer

Spoofing http_referer wth telnet

telnet www.yoursite.com 80 (press return)
GET /index.html HTTP/1.0 (press return)
Referer: http://www.hah-hah.com (press return)
(press return again)

Bootstrap 3 Glyphicons CDN

Although Bootstrap CDN restored glyphicons to bootstrap.min.css, Bootstrap CDN's Bootswatch css files doesn't include glyphicons.

For example Amelia theme: http://bootswatch.com/amelia/

Default Amelia has glyphicons in this file: http://bootswatch.com/amelia/bootstrap.min.css

But Bootstrap CDN's css file doesn't include glyphicons: http://netdna.bootstrapcdn.com/bootswatch/3.0.0/amelia/bootstrap.min.css

So as @edsioufi mentioned, you should include you should include glphicons css, if you use Bootswatch files from the bootstrap CDN. File: http://netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap-glyphicons.css

Multiple Python versions on the same machine?

I'm using Mac & the best way that worked for me is using pyenv!

The commands below are for Mac but pretty similar to Linux (see the links below)

#Install pyenv
brew update
brew install pyenv

Let's say you have python 3.6 as your primary version on your mac:

python --version 

Output:

Python <your current version>

Now Install python 3.7, first list all

pyenv install -l

Let's take 3.7.3:

pyenv install 3.7.3

Make sure to run this in the Terminal (add it to ~/.bashrc or ~/.zshrc):

export PATH="/Users/username/.pyenv:$PATH"
eval "$(pyenv init -)"

Now let's run it only on the opened terminal/shell:

pyenv shell 3.7.3

Now run

python --version

Output:

Python 3.7.3

And not less important unset it in the opened shell/iTerm:

pyenv shell --unset

You can run it globally or locally as well

How to insert TIMESTAMP into my MySQL table?

Please try CURRENT_TIME() or now() functions

"INSERT INTO contactinfo (name, email, subject, date, comments)
VALUES ('$name', '$email', '$subject', NOW(), '$comments')"

OR

"INSERT INTO contactinfo (name, email, subject, date, comments)
VALUES ('$name', '$email', '$subject', CURRENT_TIME(), '$comments')"

OR you could try with PHP date function here:

$date = date("Y-m-d H:i:s");

How to combine two or more querysets in a Django view?

In case you want to chain a lot of querysets, try this:

from itertools import chain
result = list(chain(*docs))

where: docs is a list of querysets

How do I run a Python script from C#?

Execute Python script from C

Create a C# project and write the following code.

using System;
using System.Diagnostics;
using System.IO;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            run_cmd();
        }

        private void run_cmd()
        {

            string fileName = @"C:\sample_script.py";

            Process p = new Process();
            p.StartInfo = new ProcessStartInfo(@"C:\Python27\python.exe", fileName)
            {
                RedirectStandardOutput = true,
                UseShellExecute = false,
                CreateNoWindow = true
            };
            p.Start();

            string output = p.StandardOutput.ReadToEnd();
            p.WaitForExit();

            Console.WriteLine(output);

            Console.ReadLine();

        }
    }
}

Python sample_script

print "Python C# Test"

You will see the 'Python C# Test' in the console of C#.

Android turn On/Off WiFi HotSpot programmatically

Here's the complete solution if you want to implement the wifi hotspot feature programmatically in your android app.

SOLUTION FOR API < 26:

For devices < API 26. There is no public API by Android for this purpose. So, in order to work with those APIs you've to access private APIs through reflection. It is not recommended but if you've no other options left, then here's a trick.

First of all, you need to have this permission in your manifest,

  <uses-permission  
  android:name="android.permission.WRITE_SETTINGS"  
  tools:ignore="ProtectedPermissions"/>

  <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
  <uses-permission android:name="android.permission.CHANGE_WIFI_STATE"/>
  <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>

Here's how you can ask it on run-time:

 private boolean showWritePermissionSettings() {    
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M  
    && Build.VERSION.SDK_INT < Build.VERSION_CODES.O) { 
  if (!Settings.System.canWrite(this)) {    
    Log.v("DANG", " " + !Settings.System.canWrite(this));   
    Intent intent = new Intent(android.provider.Settings.ACTION_MANAGE_WRITE_SETTINGS); 
    intent.setData(Uri.parse("package:" + this.getPackageName()));  
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); 
    this.startActivity(intent); 
    return false;   
  } 
}   
return true; //Permission already given 
}

You can then access the setWifiEnabled method through reflection. This returns true if the action you asked for is being process correctly i.e. enabling/disabling hotspot.

     public boolean setWifiEnabled(WifiConfiguration wifiConfig, boolean enabled) { 
 WifiManager wifiManager;
try {   
  if (enabled) { //disables wifi hotspot if it's already enabled    
    wifiManager.setWifiEnabled(false);  
  } 

   Method method = wifiManager.getClass()   
      .getMethod("setWifiApEnabled", WifiConfiguration.class, boolean.class);   
  return (Boolean) method.invoke(wifiManager, wifiConfig, enabled); 
} catch (Exception e) { 
  Log.e(this.getClass().toString(), "", e); 
  return false; 
}   
}

You can also get the wificonfiguration of your hotspot through reflection. I've answered that method for this question on StackOverflow.

P.S: If you don't want to turn on hotspot programmatically, you can start this intent and open the wifi settings screen for user to turn it on manually.

SOLUTION FOR API >= 26:

Finally, android released an official API for versions >= Oreo. You can just use the public exposed API by android i.e. startLocalOnlyHotspot

It turns on a local hotspot without internet access. Which thus can be used to host a server or transfer files.

It requires Manifest.permission.CHANGE_WIFI_STATE and ACCESS_FINE_LOCATION permissions.

Here's a simple example of how you can turn on hotspot using this API.

private WifiManager wifiManager;
WifiConfiguration currentConfig;
WifiManager.LocalOnlyHotspotReservation hotspotReservation;

The method to turn on hotspot:

@RequiresApi(api = Build.VERSION_CODES.O)
public void turnOnHotspot() {

      wifiManager.startLocalOnlyHotspot(new WifiManager.LocalOnlyHotspotCallback() {

        @Override
        public void onStarted(WifiManager.LocalOnlyHotspotReservation reservation) {
          super.onStarted(reservation);
          hotspotReservation = reservation;
          currentConfig = hotspotReservation.getWifiConfiguration();

          Log.v("DANG", "THE PASSWORD IS: "
              + currentConfig.preSharedKey
              + " \n SSID is : "
              + currentConfig.SSID);

          hotspotDetailsDialog();

        }

        @Override
        public void onStopped() {
          super.onStopped();
          Log.v("DANG", "Local Hotspot Stopped");
        }

        @Override
        public void onFailed(int reason) {
          super.onFailed(reason);
          Log.v("DANG", "Local Hotspot failed to start");
        }
      }, new Handler());
    }
`

Here's how you can get details of the locally created hotspot

private void hotspotDetaisDialog()
{

    Log.v(TAG, context.getString(R.string.hotspot_details_message) + "\n" + context.getString(
              R.string.hotspot_ssid_label) + " " + currentConfig.SSID + "\n" + context.getString(
              R.string.hotspot_pass_label) + " " + currentConfig.preSharedKey);

}

If it throws, a security exception even after giving the required permissions then you should try enabling your location using GPS. Here's the solution.

Recently, I've developed a demo app called Spotserve. That turns on wifi hotspot for all devices with API>=15 and hosts a demo server on that hotspot. You can check that for more details. Hope this helps!

Is there a way to avoid null check before the for-each loop iteration starts?

It's already 2017, and you can now use Apache Commons Collections4

The usage:

for(Object obj : CollectionUtils.emptyIfNull(list1)){
    // Do your stuff
}

How to add Active Directory user group as login in SQL Server

You can use T-SQL:

use master
GO
CREATE LOGIN [NT AUTHORITY\LOCALSERVICE] FROM WINDOWS WITH
DEFAULT_DATABASE=yourDbName
GO
CREATE LOGIN [NT AUTHORITY\NETWORKSERVICE] FROM WINDOWS WITH
DEFAULT_DATABASE=yourDbName

I use this as a part of restore from production server to testing machine:

USE master
GO
ALTER DATABASE yourDbName SET OFFLINE WITH ROLLBACK IMMEDIATE
RESTORE DATABASE yourDbName FROM DISK = 'd:\DropBox\backup\myDB.bak'
ALTER DATABASE yourDbName SET ONLINE
GO
CREATE LOGIN [NT AUTHORITY\LOCALSERVICE] FROM WINDOWS WITH
DEFAULT_DATABASE=yourDbName
GO
CREATE LOGIN [NT AUTHORITY\NETWORKSERVICE] FROM WINDOWS WITH
DEFAULT_DATABASE=yourDbName
GO

You will need to use localized name of services in case of German or French Windows, see How to create a SQL Server login for a service account on a non-English Windows?

How to sort a file in-place

No answers about few files, so:

sort -u file1 file2 -o file1

XML Parser for C

You can try ezxml -- it's a lightweight parser written entirely in C.

For C++ you can check out TinyXML++

Find out whether radio button is checked with JQuery?

As Parag's solution threw an error for me, here's my solution (combining David Hedlund's and Parag's):

if (!$("input[name='name']").is(':checked')) {
   alert('Nothing is checked!');
}
else {
   alert('One of the radio buttons is checked!');
}

This worked fine for me!

how to convert long date value to mm/dd/yyyy format

Try something like this:

public class test 
{  

    public static void main(String a[])
    {  
        long tmp = 1346524199000;  

        Date d = new Date(tmp);  
        System.out.println(d);  
    }  
} 

The type or namespace name could not be found

Other problem that might be causing such behavior are build configurations.

I had two projects with configurations set to be built to specific folders. Like Debug and Any CPU and in second it was Debug and x86.

What I did I went to Solution->Context menu->Properties->Configuration properties->Configuration and I set all my projects to use same configurations Debug and x86 and also checked Build tick mark.

Then projects started to build correctly and were able to see namespaces.

How do I loop through items in a list box and then remove those item?

You can't make modification to the collection being iterated within the ForEach block.

A quick fix is to iterate over a copy of the collection. An easy way to make this copy is through the ArrayList constructor. The DataRowView objects in the copied collection will refer to, and be able to modify, the same underlying data as your code.

For Each item As DataRowView In New System.Collections.ArrayList(lbOrdersNeedToBeVoided.Items)

please read http://social.msdn.microsoft.com/Forums/en-AU/vbgeneral/thread/b4d1f649-d78a-4e5b-8ad8-1940e3379bed

How to determine the current language of a wordpress page when using polylang?

pll_current_language

Returns the current language

Usage:

pll_current_language( $value ); 
  • $value => (optional) either name or locale or slug, defaults to slug

returns either the full name, or the WordPress locale (just as the WordPress core function ‘get_locale’ or the slug ( 2-letters code) of the current language.

Delay/Wait in a test case of Xcode UI testing

In my case sleep created side effect so I used wait

let _ = XCTWaiter.wait(for: [XCTestExpectation(description: "Hello World!")], timeout: 2.0)

URL Encoding using C#

I have written a C# method that url-encodes ALL symbols:

    /// <summary>
    /// !#$345Hf} ? %21%23%24%33%34%35%48%66%7D
    /// </summary>
    public static string UrlEncodeExtended( string value )
    {
        char[] chars = value.ToCharArray();
        StringBuilder encodedValue = new StringBuilder();
        foreach (char c in chars)
        {
            encodedValue.Append( "%" + ( (int)c ).ToString( "X2" ) );
        }
        return encodedValue.ToString();
    }

Vertical align middle with Bootstrap responsive grid

Add !important rule to display: table of your .v-center class.

.v-center {
    display:table !important;
    border:2px solid gray;
    height:300px;
}

Your display property is being overridden by bootstrap to display: block.

Example

What is JavaScript garbage collection?

Eric Lippert wrote a detailed blog post about this subject a while back (additionally comparing it to VBScript). More accurately, he wrote about JScript, which is Microsoft's own implementation of ECMAScript, although very similar to JavaScript. I would imagine that you can assume the vast majority of behaviour would be the same for the JavaScript engine of Internet Explorer. Of course, the implementation will vary from browser to browser, though I suspect you could take a number of the common principles and apply them to other browsers.

Quoted from that page:

JScript uses a nongenerational mark-and-sweep garbage collector. It works like this:

  • Every variable which is "in scope" is called a "scavenger". A scavenger may refer to a number, an object, a string, whatever. We maintain a list of scavengers -- variables are moved on to the scav list when they come into scope and off the scav list when they go out of scope.

  • Every now and then the garbage collector runs. First it puts a "mark" on every object, variable, string, etc – all the memory tracked by the GC. (JScript uses the VARIANT data structure internally and there are plenty of extra unused bits in that structure, so we just set one of them.)

  • Second, it clears the mark on the scavengers and the transitive closure of scavenger references. So if a scavenger object references a nonscavenger object then we clear the bits on the nonscavenger, and on everything that it refers to. (I am using the word "closure" in a different sense than in my earlier post.)

  • At this point we know that all the memory still marked is allocated memory which cannot be reached by any path from any in-scope variable. All of those objects are instructed to tear themselves down, which destroys any circular references.

The main purpose of garbage collection is to allow the programmer not to worry about memory management of the objects they create and use, though of course there's no avoiding it sometimes - it is always beneficial to have at least a rough idea of how garbage collection works.

Historical note: an earlier revision of the answer had an incorrect reference to the delete operator. In JavaScript the delete operator removes a property from an object, and is wholly different to delete in C/C++.

Loop through files in a directory using PowerShell

If you need to loop inside a directory recursively for a particular kind of file, use the below command, which filters all the files of doc file type

$fileNames = Get-ChildItem -Path $scriptPath -Recurse -Include *.doc

If you need to do the filteration on multiple types, use the below command.

$fileNames = Get-ChildItem -Path $scriptPath -Recurse -Include *.doc,*.pdf

Now $fileNames variable act as an array from which you can loop and apply your business logic.

How to send cookies in a post request with the Python Requests library?

Just to extend on the previous answer, if you are linking two requests together and want to send the cookies returned from the first one to the second one (for example, maintaining a session alive across requests) you can do:

import requests
r1 = requests.post('http://www.yourapp.com/login')
r2 = requests.post('http://www.yourapp.com/somepage',cookies=r1.cookies)

Combine two data frames by rows (rbind) when they have different sets of columns

You could also use sjmisc::add_rows(), which uses dplyr::bind_rows(), but unlike bind_rows(), add_rows() preserves attributes and hence is useful for labelled data.

See following example with a labelled dataset. The frq()-function prints frequency tables with value labels, if the data is labelled.

library(sjmisc)
library(dplyr)

data(efc)
# select two subsets, with some identical and else different columns
x1 <- efc %>% select(1:5) %>% slice(1:10)
x2 <- efc %>% select(3:7) %>% slice(11:20)

str(x1)
#> 'data.frame':    10 obs. of  5 variables:
#>  $ c12hour : num  16 148 70 168 168 16 161 110 28 40
#>   ..- attr(*, "label")= chr "average number of hours of care per week"
#>  $ e15relat: num  2 2 1 1 2 2 1 4 2 2
#>   ..- attr(*, "label")= chr "relationship to elder"
#>   ..- attr(*, "labels")= Named num  1 2 3 4 5 6 7 8
#>   .. ..- attr(*, "names")= chr  "spouse/partner" "child" "sibling" "daughter or son -in-law" ...
#>  $ e16sex  : num  2 2 2 2 2 2 1 2 2 2
#>   ..- attr(*, "label")= chr "elder's gender"
#>   ..- attr(*, "labels")= Named num  1 2
#>   .. ..- attr(*, "names")= chr  "male" "female"
#>  $ e17age  : num  83 88 82 67 84 85 74 87 79 83
#>   ..- attr(*, "label")= chr "elder' age"
#>  $ e42dep  : num  3 3 3 4 4 4 4 4 4 4
#>   ..- attr(*, "label")= chr "elder's dependency"
#>   ..- attr(*, "labels")= Named num  1 2 3 4
#>   .. ..- attr(*, "names")= chr  "independent" "slightly dependent" "moderately dependent" "severely dependent"

bind_rows(x1, x1) %>% frq(e42dep)
#> 
#> # e42dep <numeric> 
#> # total N=20  valid N=20  mean=3.70  sd=0.47
#>  
#>   val frq raw.prc valid.prc cum.prc
#>     3   6      30        30      30
#>     4  14      70        70     100
#>  <NA>   0       0        NA      NA

add_rows(x1, x1) %>% frq(e42dep)
#> 
#> # elder's dependency (e42dep) <numeric> 
#> # total N=20  valid N=20  mean=3.70  sd=0.47
#>  
#>  val                label frq raw.prc valid.prc cum.prc
#>    1          independent   0       0         0       0
#>    2   slightly dependent   0       0         0       0
#>    3 moderately dependent   6      30        30      30
#>    4   severely dependent  14      70        70     100
#>   NA                   NA   0       0        NA      NA

setup script exited with error: command 'x86_64-linux-gnu-gcc' failed with exit status 1

below answer worked for me, you can try:

sudo apt-get install python3-lxml

Using reCAPTCHA on localhost

You can write "localhost" or "127.0.0.1" but URL must be the same

Example : Google Domains Add-> localhost URL => localhost/login.php

Example : Google Domains Add-> 127.0.0.1 URL => 127.0.0.1/login.php

Why is NULL undeclared?

NULL isn't a native part of the core C++ language, but it is part of the standard library. You need to include one of the standard header files that include its definition. #include <cstddef> or #include <stddef.h> should be sufficient.

The definition of NULL is guaranteed to be available if you include cstddef or stddef.h. It's not guaranteed, but you are very likely to get its definition included if you include many of the other standard headers instead.

Run chrome in fullscreen mode on Windows

Update 03-Oct-19

new script that displays 10second countdown then launches chrome/chromiumn in fullscreen kiosk mode.

more updates to chrome required script update to allow autoplaying video with audio. Note --overscroll-history-navigation=0 isn't working currently will need to disable this flag by going to chrome://flags/#overscroll-history-navigation in your browser and setting to disabled.

@echo off
echo Countdown to application launch...
timeout /t 10
"C:\Program Files (x86)\chrome-win32\chrome.exe" --chrome --kiosk http://localhost/xxxx --incognito --disable-pinch --no-user-gesture-required --overscroll-history-navigation=0
exit

might need to set chrome://flags/#autoplay-policy if running an older version of chrome (60 below)

Update 11-May-16

There have been many updates to chrome since I posted this and have had to alter the script alot to keep it working as I needed.

Couple of issues with newer versions of chrome:

  • built in pinch to zoom
  • Chrome restore error always showing after forced shutdown
  • auto update popup

Because of the restore error switched out to incognito mode as this launches a clear version all the time and does not save what the user was viewing and so if it crashes there is nothing to restore. Also the auto up in newer versions of chrome being a pain to try and disable I switched out to use chromium as it does not auto update and still gives all the modern features of chrome. Note make sure you download the top version of chromium this comes with all audio and video codecs as the basic version of chromium does not support all codecs.

Chromium download link

@echo off

echo Step 1 of 2: Waiting a few seconds before starting the Kiosk...

"C:\windows\system32\ping" -n 5 -w 1000 127.0.0.1 >NUL

echo Step 2 of 5: Waiting a few more seconds before starting the browser...

"C:\windows\system32\ping" -n 5 -w 1000 127.0.0.1 >NUL

echo Final 'invisible' step: Starting the browser, Finally...

"C:\Program Files (x86)\Google\Chromium\chrome.exe" --chrome --kiosk http://127.0.0.1/xxxx --incognito --disable-pinch --overscroll-history-navigation=0

exit

Outdated

I use this for exhibitions to lock down screens. I think its what your looking for.

  • Start chrome and go to www.google.com drag and drop the url out onto the desktop
  • rename it to something handy for this example google_homepage
  • drop this now into your c directory, click on my computer c: and drop this file in there
  • start chrome again go to settings and under on start up select open a specific page and set your home page here.

Next part is the script that I use to start close and restart chrome again in kiosk mode. The locations is where I have chrome installed so it might be abit different for you depending on your install.

Open your text editor of choice or just notepad and past the below code in, make sure its in the same format/order as below. Save it to your desktop as what ever you like so for this example chrome_startup_script.txt next right click it and rename, remove the txt from the end and put in bat instead. double click this to launch the script to see if its working correctly.

A command line box should appear and run through the script, chrome will start and then close down the reason to do this is to remove any error reports such as if the pc crashed, when chrome starts again without this it would show the yellow error bar at the top saying chrome did not shut down properly would you like to restore it. After a few seconds chrome should start again and in kiosk mode and will point to what ever homepage you have set.

@echo off
echo Step 1 of 5: Waiting a few seconds before starting the Kiosk...
"C:\windows\system32\ping" -n 31 -w 1000 127.0.0.1 >NUL
echo Step 2 of 5: Starting browser as a pre-start to delete error messages...
"C:\google_homepage.url"
echo Step 3 of 5: Waiting a few seconds before killing the browser task...
"C:\windows\system32\ping" -n 11 -w 1000 127.0.0.1 >NUL
echo Step 4 of 5: Killing the browser task gracefully to avoid session restore...
Taskkill /IM chrome.exe
echo Step 5 of 5: Waiting a few seconds before restarting the browser...
"C:\windows\system32\ping" -n 11 -w 1000 127.0.0.1 >NUL
echo Final 'invisible' step: Starting the browser, Finally...
"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --kiosk --overscroll-history-navigation=0"
exit

Note: The number after the -n of the ping is the amount of seconds (minus one second) to wait before starting the link (or application in the next line)

Finally if this is all working then you can drag and drop the .bat file into the startup folder in windows and this script will launch each time windows starts.


Update:

With recent versions of chrome they have really got into enabling touch gestures, this means that swiping left or right on a touchscreen will cause the browser to go forward or backward in history. To prevent this we need to disable the history navigation on the back and forward buttons to do that add the following --overscroll-history-navigation=0 to the end of the script.

How to take character input in java

I had the same struggle and I this is what I used:

} public static void main(String[] args) {

Scanner scan = new Scanner(System.in);
System.out.print("Please enter the string: ");
String input = scan.next();
System.out.print("Please enter the required symbol: ");
String symbol = scan.next();        
char symbolChar = symbol.charAt(0);

This works just fine. The idea is to get from the string the only char in it.

Can you hide the controls of a YouTube embed without enabling autoplay?

To remove you tube controls and title you can do something like this

_x000D_
_x000D_
<iframe width="560" height="315" src="https://www.youtube.com/embed/zP0Wnb9RI9Q?autoplay=1&showinfo=0&controls=0" frameborder="0" allowfullscreen ></iframe>
_x000D_
_x000D_
_x000D_

code with output

showinfo=0 is used to remove title and &controls=0 is used for remove controls like volume,play,pause,expend.

String representation of an Enum

Unfortunately reflection to get attributes on enums is quite slow:

See this question: Anyone know a quick way to get to custom attributes on an enum value?

The .ToString() is quite slow on enums too.

You can write extension methods for enums though:

public static string GetName( this MyEnum input ) {
    switch ( input ) {
        case MyEnum.WINDOWSAUTHENTICATION:
            return "Windows";
        //and so on
    }
}

This isn't great, but will be quick and not require the reflection for attributes or field name.


C#6 Update

If you can use C#6 then the new nameof operator works for enums, so nameof(MyEnum.WINDOWSAUTHENTICATION) will be converted to "WINDOWSAUTHENTICATION" at compile time, making it the quickest way to get enum names.

Note that this will convert the explicit enum to an inlined constant, so it doesn't work for enums that you have in a variable. So:

nameof(AuthenticationMethod.FORMS) == "FORMS"

But...

var myMethod = AuthenticationMethod.FORMS;
nameof(myMethod) == "myMethod"

How to return rows from left table not found in right table?

Try This

SELECT f.*
FROM first_table f LEFT JOIN second_table s ON f.key=s.key
WHERE s.key is NULL

For more please read this article : Joins in Sql Server

enter image description here

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

http://dev.mysql.com/doc/refman/5.0/en/insert-select.html

For case1:

INSERT INTO TAB_STUDENT(name_student, id_teacher_fk)
SELECT 'Joe The Student', id_teacher
  FROM TAB_TEACHER
 WHERE name_teacher = 'Professor Jack'
 LIMIT 1

For case2 you just have to do 2 separate insert statements

Convert DateTime to a specified Format

Easy peasy:

var date = DateTime.Parse("14/11/2011"); // may need some Culture help here
Console.Write(date.ToString("yyyy-MM-dd"));

Take a look at DateTime.ToString() method, Custom Date and Time Format Strings and Standard Date and Time Format Strings

string customFormattedDateTimeString = DateTime.Now.ToString("yyyy-MM-dd");

C# Clear all items in ListView

I would suggest to remove the rows from the underlying DataTable, or if you don't need the datatable anymore, set the datasource to null.

Concatenating bits in VHDL

The concatenation operator '&' is allowed on the right side of the signal assignment operator '<=', only

How do I get the value of text input field using JavaScript?

Just try this ..

_x000D_
_x000D_
function handleValueChange() {
    var y = document.getElementById('textbox_id').value;
    var x = document.getElementById('result');
    x.innerHTML = y;
}

function changeTextarea() {
  var a = document.getElementById('text-area').value;
  var b = document.getElementById('text-area-result');
  b.innerHTML = a;
}
_x000D_
input {
  padding: 5px;
}

p {
  white-space: pre;
}
_x000D_
<input type="text" id="textbox_id" placeholder="Enter string here..." oninput="handleValueChange()">
<p id="result"></p>

<textarea name="" id="text-area" cols="20" rows="5" oninput="changeTextarea()"></textarea>
<p id="text-area-result"></p>
_x000D_
_x000D_
_x000D_

find index of an int in a list

Use the .IndexOf() method of the list. Specs for the method can be found on MSDN.

Adding items to an object through the .push() method

so it's easy)))

Watch this...

    var stuff = {};
    $('input[type=checkbox]').each(function(i, e) {
        stuff[i] = e.checked;
    });

And you will have:

Object {0: true, 1: false, 2: false, 3: false}

Or:

$('input[type=checkbox]').each(function(i, e) {
    stuff['row'+i] = e.checked;
});

You will have:

Object {row0: true, row1: false, row2: false, row3: false}

Or:

$('input[type=checkbox]').each(function(i, e) {
    stuff[e.className+i] = e.checked;
});

You will have:

Object {checkbox0: true, checkbox1: false, checkbox2: false, checkbox3: false}

Simple UDP example to send and receive data from same socket

(I presume you are aware that using UDP(User Datagram Protocol) does not guarantee delivery, checks for duplicates and congestion control and will just answer your question).

In your server this line:

var data = udpServer.Receive(ref groupEP);

re-assigns groupEP from what you had to a the address you receive something on.

This line:

udpServer.Send(new byte[] { 1 }, 1); 

Will not work since you have not specified who to send the data to. (It works on your client because you called connect which means send will always be sent to the end point you connected to, of course we don't want that on the server as we could have many clients). I would:

UdpClient udpServer = new UdpClient(UDP_LISTEN_PORT);

while (true)
{
    var remoteEP = new IPEndPoint(IPAddress.Any, 11000);
    var data = udpServer.Receive(ref remoteEP);
    udpServer.Send(new byte[] { 1 }, 1, remoteEP); // if data is received reply letting the client know that we got his data          
}

Also if you have server and client on the same machine you should have them on different ports.

Show MySQL host via SQL Command

show variables where Variable_name='hostname'; 

That could help you !!

Connection Java-MySql : Public Key Retrieval is not allowed

If you are getting the following error while connecting the mysql (either local or mysql container running the mysql):

java.sql.SQLNonTransientConnectionException: Public Key Retrieval is not allowed

Solution: Add the following line in your database service:

command: --default-authentication-plugin=mysql_native_password

Find the unique values in a column and then sort them

sorted return a new sorted list from the items in iterable.

CODE

import pandas as pd
df = pd.DataFrame({'A':[1,1,3,2,6,2,8]})
a = df['A'].unique()
print sorted(a)

OUTPUT

[1, 2, 3, 6, 8]

How to Remove the last char of String in C#?

newString = yourString.Substring(0, yourString.length -1);

Android Studio: Drawable Folder: How to put Images for Multiple dpi?

You don't create subfolders of the drawable folder but rather 'sibling' folders next to it under the /res folder for the different screen densities or screen sizes. The /drawable folder (without any dimension) is mostly used for drawables that don't relate to any screen sizes like selectors.

See this screenshot (use the name drawable-hdpi instead of mipmap-hdpi):

enter image description here

How do I use typedef and typedef enum in C?

typedef enum state {DEAD,ALIVE} State;
|     | |                     | |   |^ terminating semicolon, required! 
|     | |   type specifier    | |   |
|     | |                     | ^^^^^  declarator (simple name)
|     | |                     |    
|     | ^^^^^^^^^^^^^^^^^^^^^^^  
|     |
^^^^^^^-- storage class specifier (in this case typedef)

The typedef keyword is a pseudo-storage-class specifier. Syntactically, it is used in the same place where a storage class specifier like extern or static is used. It doesn't have anything to do with storage. It means that the declaration doesn't introduce the existence of named objects, but rather, it introduces names which are type aliases.

After the above declaration, the State identifier becomes an alias for the type enum state {DEAD,ALIVE}. The declaration also provides that type itself. However that isn't typedef doing it. Any declaration in which enum state {DEAD,ALIVE} appears as a type specifier introduces that type into the scope:

enum state {DEAD, ALIVE} stateVariable;

If enum state has previously been introduced the typedef has to be written like this:

typedef enum state State;

otherwise the enum is being redefined, which is an error.

Like other declarations (except function parameter declarations), the typedef declaration can have multiple declarators, separated by a comma. Moreover, they can be derived declarators, not only simple names:

typedef unsigned long ulong, *ulongptr;
|     | |           | |  1 | |   2   |
|     | |           | |    | ^^^^^^^^^--- "pointer to" declarator
|     | |           | ^^^^^^------------- simple declarator
|     | ^^^^^^^^^^^^^-------------------- specifier-qualifier list
^^^^^^^---------------------------------- storage class specifier

This typedef introduces two type names ulong and ulongptr, based on the unsigned long type given in the specifier-qualifier list. ulong is just a straight alias for that type. ulongptr is declared as a pointer to unsigned long, thanks to the * syntax, which in this role is a kind of type construction operator which deliberately mimics the unary * for pointer dereferencing used in expressions. In other words ulongptr is an alias for the "pointer to unsigned long" type.

Alias means that ulongptr is not a distinct type from unsigned long *. This is valid code, requiring no diagnostic:

unsigned long *p = 0;
ulongptr q = p;

The variables q and p have exactly the same type.

The aliasing of typedef isn't textual. For instance if user_id_t is a typedef name for the type int, we may not simply do this:

unsigned user_id_t uid;  // error! programmer hoped for "unsigned int uid". 

This is an invalid type specifier list, combining unsigned with a typedef name. The above can be done using the C preprocessor:

#define user_id_t int
unsigned user_id_t uid;

whereby user_id_t is macro-expanded to the token int prior to syntax analysis and translation. While this may seem like an advantage, it is a false one; avoid this in new programs.

Among the disadvantages that it doesn't work well for derived types:

 #define silly_macro int *

 silly_macro not, what, you, think;

This declaration doesn't declare what, you and think as being of type "pointer to int" because the macro-expansion is:

 int * not, what, you, think;

The type specifier is int, and the declarators are *not, what, you and think. So not has the expected pointer type, but the remaining identifiers do not.

And that's probably 99% of everything about typedef and type aliasing in C.

Double Iteration in List Comprehension

This memory technic helps me a lot:

[ <RETURNED_VALUE> <OUTER_LOOP1> <INNER_LOOP2> <INNER_LOOP3> ... <OPTIONAL_IF> ]

And now you can think about Return + Outer-loop as the only Right Order

Knowing above, the order in list comprehensive even for 3 loops seem easy:


c=[111, 222, 333]
b=[11, 22, 33]
a=[1, 2, 3]

print(
  [
    (i, j, k)                            # <RETURNED_VALUE> 
    for i in a for j in b for k in c     # in order: loop1, loop2, loop3
    if i < 2 and j < 20 and k < 200      # <OPTIONAL_IF>
  ]
)
[(1, 11, 111)]

because the above is just a:

for i in a:                         # outer loop1 GOES SECOND
  for j in b:                       # inner loop2 GOES THIRD
    for k in c:                     # inner loop3 GOES FOURTH
      if i < 2 and j < 20 and k < 200:
        print((i, j, k))            # returned value GOES FIRST

for iterating one nested list/structure, technic is the same: for a from the question:

a = [[1,2],[3,4]]
[i2    for i1 in a      for i2 in i1]
which return [1, 2, 3, 4]

for one another nested level

a = [[[1, 2], [3, 4]], [[5, 6], [7, 8, 9]], [[10]]]
[i3    for i1 in a      for i2 in i1     for i3 in i2]
which return [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

and so on