Programs & Examples On #Acceleratorkey

A set of one or several keys to quickly access a menu or function. It is also called a hot key.

How to verify that a specific method was not called using Mockito?

As a more general pattern to follow, I tend to use an @After block in the test:

@After
public void after() {
    verifyNoMoreInteractions(<your mock1>, <your mock2>...);
}

Then the test is free to verify only what should be called.

Also, I found that I often forgot to check for "no interactions", only to later discover that things were being called that shouldn't have been.

So I find this pattern useful for catching all unexpected calls that haven't specifically been verified.

How can I specify working directory for popen

subprocess.Popen takes a cwd argument to set the Current Working Directory; you'll also want to escape your backslashes ('d:\\test\\local'), or use r'd:\test\local' so that the backslashes aren't interpreted as escape sequences by Python. The way you have it written, the \t part will be translated to a tab.

So, your new line should look like:

subprocess.Popen(r'c:\mytool\tool.exe', cwd=r'd:\test\local')

To use your Python script path as cwd, import os and define cwd using this:

os.path.dirname(os.path.realpath(__file__)) 

Add/delete row from a table

JavaScript with a few modifications:

function deleteRow(btn) {
  var row = btn.parentNode.parentNode;
  row.parentNode.removeChild(row);
}

And the HTML with a little difference:

<table id="dsTable">
  <tbody>
    <tr>
      <td>Relationship Type</td>
      <td>Date of Birth</td>
      <td>Gender</td>
    </tr>
    <tr>
      <td>Spouse</td>
      <td>1980-22-03</td>
      <td>female</td>
      <td><input type="button" value="Add" onclick="add()"/></td>
      <td><input type="button" value="Delete" onclick="deleteRow(this)"/></td>
    </tr>
    <tr>
      <td>Child</td>
      <td>2008-23-06</td>
      <td>female</td>
      <td><input type="button" value="Add" onclick="add()"/></td>
      <td><input type="button" value="Delete" onclick="deleteRow(this)"/></td>
    </tr>
  </tbody>
</table>???????????????????????????????????

How to add buttons at top of map fragment API v2 layout

Button Above The Map

If this is what you want ...simply add button inside the Fragment.

<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/map"
    android:name="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.LocationChooser">


    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="right|top"
        android:text="Demo Button" 
        android:padding="10dp"
        android:layout_marginTop="20dp"
        android:paddingRight="10dp"/>

</fragment>

Multiple aggregations of the same column using pandas GroupBy.agg()

TLDR; Pandas groupby.agg has a new, easier syntax for specifying (1) aggregations on multiple columns, and (2) multiple aggregations on a column. So, to do this for pandas >= 0.25, use

df.groupby('dummy').agg(Mean=('returns', 'mean'), Sum=('returns', 'sum'))

           Mean       Sum
dummy                    
1      0.036901  0.369012

OR

df.groupby('dummy')['returns'].agg(Mean='mean', Sum='sum')

           Mean       Sum
dummy                    
1      0.036901  0.369012

Pandas >= 0.25: Named Aggregation

Pandas has changed the behavior of GroupBy.agg in favour of a more intuitive syntax for specifying named aggregations. See the 0.25 docs section on Enhancements as well as relevant GitHub issues GH18366 and GH26512.

From the documentation,

To support column-specific aggregation with control over the output column names, pandas accepts the special syntax in GroupBy.agg(), known as “named aggregation”, where

  • The keywords are the output column names
  • The values are tuples whose first element is the column to select and the second element is the aggregation to apply to that column. Pandas provides the pandas.NamedAgg namedtuple with the fields ['column', 'aggfunc'] to make it clearer what the arguments are. As usual, the aggregation can be a callable or a string alias.

You can now pass a tuple via keyword arguments. The tuples follow the format of (<colName>, <aggFunc>).

import pandas as pd

pd.__version__                                                                                                                            
# '0.25.0.dev0+840.g989f912ee'

# Setup
df = pd.DataFrame({'kind': ['cat', 'dog', 'cat', 'dog'],
                   'height': [9.1, 6.0, 9.5, 34.0],
                   'weight': [7.9, 7.5, 9.9, 198.0]
})

df.groupby('kind').agg(
    max_height=('height', 'max'), min_weight=('weight', 'min'),)

      max_height  min_weight
kind                        
cat          9.5         7.9
dog         34.0         7.5

Alternatively, you can use pd.NamedAgg (essentially a namedtuple) which makes things more explicit.

df.groupby('kind').agg(
    max_height=pd.NamedAgg(column='height', aggfunc='max'), 
    min_weight=pd.NamedAgg(column='weight', aggfunc='min')
)

      max_height  min_weight
kind                        
cat          9.5         7.9
dog         34.0         7.5

It is even simpler for Series, just pass the aggfunc to a keyword argument.

df.groupby('kind')['height'].agg(max_height='max', min_height='min')    

      max_height  min_height
kind                        
cat          9.5         9.1
dog         34.0         6.0       

Lastly, if your column names aren't valid python identifiers, use a dictionary with unpacking:

df.groupby('kind')['height'].agg(**{'max height': 'max', ...})

Pandas < 0.25

In more recent versions of pandas leading upto 0.24, if using a dictionary for specifying column names for the aggregation output, you will get a FutureWarning:

df.groupby('dummy').agg({'returns': {'Mean': 'mean', 'Sum': 'sum'}})
# FutureWarning: using a dict with renaming is deprecated and will be removed 
# in a future version

Using a dictionary for renaming columns is deprecated in v0.20. On more recent versions of pandas, this can be specified more simply by passing a list of tuples. If specifying the functions this way, all functions for that column need to be specified as tuples of (name, function) pairs.

df.groupby("dummy").agg({'returns': [('op1', 'sum'), ('op2', 'mean')]})

        returns          
            op1       op2
dummy                    
1      0.328953  0.032895

Or,

df.groupby("dummy")['returns'].agg([('op1', 'sum'), ('op2', 'mean')])

            op1       op2
dummy                    
1      0.328953  0.032895

Comparing two columns, and returning a specific adjacent cell in Excel

Here is what needs to go in D1: =VLOOKUP(C1, $A$1:$B$4, 2, FALSE)

You should then be able to copy this down to the rest of column D.

How do I auto-resize an image to fit a 'div' container?

Do not apply an explicit width or height to the image tag. Instead, give it:

max-width:100%;
max-height:100%;

Also, height: auto; if you want to specify a width only.

Example: http://jsfiddle.net/xwrvxser/1/

_x000D_
_x000D_
img {_x000D_
    max-width: 100%;_x000D_
    max-height: 100%;_x000D_
}_x000D_
_x000D_
.portrait {_x000D_
    height: 80px;_x000D_
    width: 30px;_x000D_
}_x000D_
_x000D_
.landscape {_x000D_
    height: 30px;_x000D_
    width: 80px;_x000D_
}_x000D_
_x000D_
.square {_x000D_
    height: 75px;_x000D_
    width: 75px;_x000D_
}
_x000D_
Portrait Div_x000D_
<div class="portrait">_x000D_
    <img src="http://i.stack.imgur.com/xkF9Q.jpg">_x000D_
</div>_x000D_
_x000D_
Landscape Div_x000D_
<div class="landscape">_x000D_
    <img src="http://i.stack.imgur.com/xkF9Q.jpg">_x000D_
</div>_x000D_
_x000D_
Square Div_x000D_
<div class="square">_x000D_
    <img src="http://i.stack.imgur.com/xkF9Q.jpg">_x000D_
</div>
_x000D_
_x000D_
_x000D_

What's the difference between .so, .la and .a library files?

.so files are dynamic libraries. The suffix stands for "shared object", because all the applications that are linked with the library use the same file, rather than making a copy in the resulting executable.

.a files are static libraries. The suffix stands for "archive", because they're actually just an archive (made with the ar command -- a predecessor of tar that's now just used for making libraries) of the original .o object files.

.la files are text files used by the GNU "libtools" package to describe the files that make up the corresponding library. You can find more information about them in this question: What are libtool's .la file for?

Static and dynamic libraries each have pros and cons.

Static pro: The user always uses the version of the library that you've tested with your application, so there shouldn't be any surprising compatibility problems.

Static con: If a problem is fixed in a library, you need to redistribute your application to take advantage of it. However, unless it's a library that users are likely to update on their own, you'd might need to do this anyway.

Dynamic pro: Your process's memory footprint is smaller, because the memory used for the library is amortized among all the processes using the library.

Dynamic pro: Libraries can be loaded on demand at run time; this is good for plugins, so you don't have to choose the plugins to be used when compiling and installing the software. New plugins can be added on the fly.

Dynamic con: The library might not exist on the system where someone is trying to install the application, or they might have a version that's not compatible with the application. To mitigate this, the application package might need to include a copy of the library, so it can install it if necessary. This is also often mitigated by package managers, which can download and install any necessary dependencies.

Dynamic con: Link-Time Optimization is generally not possible, so there could possibly be efficiency implications in high-performance applications. See the Wikipedia discussion of WPO and LTO.

Dynamic libraries are especially useful for system libraries, like libc. These libraries often need to include code that's dependent on the specific OS and version, because kernel interfaces have changed. If you link a program with a static system library, it will only run on the version of the OS that this library version was written for. But if you use a dynamic library, it will automatically pick up the library that's installed on the system you run on.

npm ERR! registry error parsing json - While trying to install Cordova for Ionic Framework in Windows 8

I had similar problem. I r?n npm cache clear, closed android SDK manager(which was open before) and re-ran npm install -g cordova and that was enough to solve the problem.

Starting ssh-agent on Windows 10 fails: "unable to start ssh-agent service, error :1058"

Yeah, as others have suggested, this error seems to mean that ssh-agent is installed but its service (on windows) hasn't been started.

You can check this by running in Windows PowerShell:

> Get-Service ssh-agent

And then check the output of status is not running.

Status   Name               DisplayName
------   ----               -----------
Stopped  ssh-agent          OpenSSH Authentication Agent

Then check that the service has been disabled by running

> Get-Service ssh-agent | Select StartType

StartType
---------
Disabled

I suggest setting the service to start manually. This means that as soon as you run ssh-agent, it'll start the service. You can do this through the Services GUI or you can run the command in admin mode:

 > Get-Service -Name ssh-agent | Set-Service -StartupType Manual

Alternatively, you can set it through the GUI if you prefer.

services.msc showing the properties of the OpenSSH Agent

Effectively use async/await with ASP.NET Web API

I am not very sure whether it will make any difference in performance of my API.

Bear in mind that the primary benefit of asynchronous code on the server side is scalability. It won't magically make your requests run faster. I cover several "should I use async" considerations in my article on async ASP.NET.

I think your use case (calling other APIs) is well-suited for asynchronous code, just bear in mind that "asynchronous" does not mean "faster". The best approach is to first make your UI responsive and asynchronous; this will make your app feel faster even if it's slightly slower.

As far as the code goes, this is not asynchronous:

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountries()
{
  var response = _service.Process<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
  return Task.FromResult(response);
}

You'd need a truly asynchronous implementation to get the scalability benefits of async:

public async Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return await _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Or (if your logic in this method really is just a pass-through):

public Task<BackOfficeResponse<List<Country>>> ReturnAllCountriesAsync()
{
  return _service.ProcessAsync<List<Country>>(BackOfficeEndpoint.CountryEndpoint, "returnCountries");
}

Note that it's easier to work from the "inside out" rather than the "outside in" like this. In other words, don't start with an asynchronous controller action and then force downstream methods to be asynchronous. Instead, identify the naturally asynchronous operations (calling external APIs, database queries, etc), and make those asynchronous at the lowest level first (Service.ProcessAsync). Then let the async trickle up, making your controller actions asynchronous as the last step.

And under no circumstances should you use Task.Run in this scenario.

SQLite with encryption/password protection

Keep in mind, the following is not intended to be a substitute for a proper security solution.

After playing around with this for four days, I've put together a solution using only the open source System.Data.SQLite package from NuGet. I don't know how much protection this provides. I'm only using it for my own course of study. This will create the DB, encrypt it, create a table, and add data.

using System.Data.SQLite;

namespace EncryptDB
{
    class Program
    {
        static void Main(string[] args)
        {
            string connectionString = @"C:\Programming\sqlite3\db.db";
            string passwordString = "password";
            byte[] passwordBytes = GetBytes(passwordString);
            SQLiteConnection.CreateFile(connectionString);
            SQLiteConnection conn = new SQLiteConnection("Data Source=" + connectionString + ";Version=3;");
            conn.SetPassword(passwordBytes);
            conn.Open();
            SQLiteCommand sqlCmd = new SQLiteCommand("CREATE TABLE data(filename TEXT, filepath TEXT, filelength INTEGER, directory TEXT)", conn);
            sqlCmd.ExecuteNonQuery();
            sqlCmd = new SQLiteCommand("INSERT INTO data VALUES('name', 'path', 200, 'dir')", conn);
            sqlCmd.ExecuteNonQuery();
            conn.Close();
        }
        static byte[] GetBytes(string str)
        {
            byte[] bytes = new byte[str.Length * sizeof(char)];
            bytes = System.Text.Encoding.Default.GetBytes(str);
            return bytes;
        }
    }
}

Optionally, you can remove conn.SetPassword(passwordBytes);, and replace it with conn.ChangePassword("password"); which needs to be placed after conn.Open(); instead of before. Then you won't need the GetBytes method.

To decrypt, it's just a matter of putting the password in your connection string before the call to open.

        string filename = @"C:\Programming\sqlite3\db.db";
        string passwordString = "password";
        SQLiteConnection conn = new SQLiteConnection("Data Source=" + filename + ";Version=3;Password=" + passwordString + ";");
        conn.Open();

How to check the exit status using an if statement

Using zsh you can simply use:

if [[ $(false)? -eq 1 ]]; then echo "yes" ;fi

When using bash & set -e is on you can use:

false || exit_code=$?
if [[ ${exit_code} -ne 0 ]]; then echo ${exit_code}; fi

How do I get my C# program to sleep for 50 msec?

Use this code

using System.Threading;
// ...
Thread.Sleep(50);

Can a CSS class inherit one or more other classes?

For those who are not satisfied with the mentioned (excellent) posts, you can use your programming skills to make a variable (PHP or whichever) and have it store the multiple class names.

That's the best hack I could come up with.

<style>
.red { color: red; }
.bold { font-weight: bold; }
</style>

<? define('DANGERTEXT','red bold'); ?>

Then apply the global variable to the element you desire rather than the class names themselves

<span class="<?=DANGERTEXT?>"> Le Champion est Ici </span>

Composer: file_put_contents(./composer.json): failed to open stream: Permission denied

To resolve this, you should open up a terminal window and type this command:

sudo chown -R user ~/.composer (with user being your current user, in your case, kramer65)

After you have ran this command, you should have permission to run your composer global require command.

You may also need to remove the .composer file from the current directory, to do this open up a terminal window and type this command:

sudo rm -rf .composer

How to close the command line window after running a batch file?

Your code is absolutely fine. It just needs "exit 0" for a cleaner exit.

 tncserver.exe C:\Work -p4 -b57600 -r -cFE -tTNC426B
 exit 0

get the latest fragment in backstack

Looks like something has changed for the better, because code below works perfectly for me, but I didn't find it in already provided answers.

Kotlin:

supportFragmentManager.fragments[supportFragmentManager.fragments.size - 1]

Java:

getSupportFragmentManager().getFragments()
.get(getSupportFragmentManager().getFragments().size() - 1)

Difference between webdriver.get() and webdriver.navigate()

Not sure it applies here also but in the case of protractor when using navigate().to(...) the history is being kept but when using get() it is lost.

One of my test was failing because I was using get() 2 times in a row and then doing a navigate().back(). Because the history was lost, when going back it went to the about page and an error was thrown:

Error: Error while waiting for Protractor to sync with the page: {}

Print content of JavaScript object?

Simple function to alert contents of an object or an array .
Call this function with an array or string or an object it alerts the contents.

Function

function print_r(printthis, returnoutput) {
    var output = '';

    if($.isArray(printthis) || typeof(printthis) == 'object') {
        for(var i in printthis) {
            output += i + ' : ' + print_r(printthis[i], true) + '\n';
        }
    }else {
        output += printthis;
    }
    if(returnoutput && returnoutput == true) {
        return output;
    }else {
        alert(output);
    }
}

Usage

var data = [1, 2, 3, 4];
print_r(data);

How to set timeout for a line of c# code

I use something like this (you should add code to deal with the various fails):

    var response = RunTaskWithTimeout<ReturnType>(
        (Func<ReturnType>)delegate { return SomeMethod(someInput); }, 30);


    /// <summary>
    /// Generic method to run a task on a background thread with a specific timeout, if the task fails,
    /// notifies a user
    /// </summary>
    /// <typeparam name="T">Return type of function</typeparam>
    /// <param name="TaskAction">Function delegate for task to perform</param>
    /// <param name="TimeoutSeconds">Time to allow before task times out</param>
    /// <returns></returns>
    private T RunTaskWithTimeout<T>(Func<T> TaskAction, int TimeoutSeconds)
    {
        Task<T> backgroundTask;

        try
        {
            backgroundTask = Task.Factory.StartNew(TaskAction);
            backgroundTask.Wait(new TimeSpan(0, 0, TimeoutSeconds));
        }
        catch (AggregateException ex)
        {
            // task failed
            var failMessage = ex.Flatten().InnerException.Message);
            return default(T);
        }
        catch (Exception ex)
        {
            // task failed
            var failMessage = ex.Message;
            return default(T);
        }

        if (!backgroundTask.IsCompleted)
        {
            // task timed out
            return default(T);
        }

        // task succeeded
        return backgroundTask.Result;
    }

New features in java 7

In addition to what John Skeet said, here's an overview of the Java 7 project. It includes a list and description of the features.

Note: JDK 7 was released on July 28, 2011, so you should now go to the official java SE site.

How to check a string against null in java?

There are two ways to do it..Say String==null or string.equals()..

public class IfElse {

    public int ifElseTesting(String a){
        //return null;
        return (a== null)? 0: a.length();
    }

}

public class ShortCutifElseTesting {

    public static void main(String[] args) {

        Scanner scanner=new Scanner(System.in);
        System.out.println("enter the string please:");
        String a=scanner.nextLine();
        /*
        if (a.equals(null)){
            System.out.println("you are not correct");
        }
        else if(a.equals("bangladesh")){
            System.out.println("you are right");
        }
        else
            System.out.println("succesful tested");

        */
        IfElse ie=new IfElse();
        int result=ie.ifElseTesting(a);
        System.out.println(result);

    }

}

Check this example..Here is an another example of shortcut version of If Else..

Change values on matplotlib imshow() graph axis

I would try to avoid changing the xticklabels if possible, otherwise it can get very confusing if you for example overplot your histogram with additional data.

Defining the range of your grid is probably the best and with imshow it can be done by adding the extent keyword. This way the axes gets adjusted automatically. If you want to change the labels i would use set_xticks with perhaps some formatter. Altering the labels directly should be the last resort.

fig, ax = plt.subplots(figsize=(6,6))

ax.imshow(hist, cmap=plt.cm.Reds, interpolation='none', extent=[80,120,32,0])
ax.set_aspect(2) # you may also use am.imshow(..., aspect="auto") to restore the aspect ratio

enter image description here

biggest integer that can be stored in a double

9007199254740992 (that's 9,007,199,254,740,992) with no guarantees :)

Program

#include <math.h>
#include <stdio.h>

int main(void) {
  double dbl = 0; /* I started with 9007199254000000, a little less than 2^53 */
  while (dbl + 1 != dbl) dbl++;
  printf("%.0f\n", dbl - 1);
  printf("%.0f\n", dbl);
  printf("%.0f\n", dbl + 1);
  return 0;
}

Result

9007199254740991
9007199254740992
9007199254740992

Javascript Uncaught Reference error Function is not defined

Change the wrapping from "onload" to "No wrap - in <body>"

The function defined has a different scope.

Filter object properties by key in ES6

Another short way

_x000D_
_x000D_
function filterByKey(v,keys){
  const newObj ={};
  keys.forEach(key=>{v[key]?newObj[key]=v[key]:''});
  return newObj;
}

//given
let obj ={ foo: "bar", baz: 42,baz2:"blabla" , "spider":"man", monkey:true};

//when
let outObj =filterByKey(obj,["bar","baz2","monkey"]);

//then 
console.log(outObj);
  //{
  //  "baz2": "blabla",
  //  "monkey": true
  //}
_x000D_
_x000D_
_x000D_

How to convert numbers between hexadecimal and decimal

Hex to Decimal Conversion

Convert.ToInt32(number, 16);

Decimal to Hex Conversion

int.Parse(number, System.Globalization.NumberStyles.HexNumber)

For more details Check this article

How do I create a self-signed certificate for code signing on Windows?

Updated Answer

If you are using the following Windows versions or later: Windows Server 2012, Windows Server 2012 R2, or Windows 8.1 then MakeCert is now deprecated, and Microsoft recommends using the PowerShell Cmdlet New-SelfSignedCertificate.

If you're using an older version such as Windows 7, you'll need to stick with MakeCert or another solution. Some people suggest the Public Key Infrastructure Powershell (PSPKI) Module.

Original Answer

While you can create a self-signed code-signing certificate (SPC - Software Publisher Certificate) in one go, I prefer to do the following:

Creating a self-signed certificate authority (CA)

makecert -r -pe -n "CN=My CA" -ss CA -sr CurrentUser ^
         -a sha256 -cy authority -sky signature -sv MyCA.pvk MyCA.cer

(^ = allow batch command-line to wrap line)

This creates a self-signed (-r) certificate, with an exportable private key (-pe). It's named "My CA", and should be put in the CA store for the current user. We're using the SHA-256 algorithm. The key is meant for signing (-sky).

The private key should be stored in the MyCA.pvk file, and the certificate in the MyCA.cer file.

Importing the CA certificate

Because there's no point in having a CA certificate if you don't trust it, you'll need to import it into the Windows certificate store. You can use the Certificates MMC snapin, but from the command line:

certutil -user -addstore Root MyCA.cer

Creating a code-signing certificate (SPC)

makecert -pe -n "CN=My SPC" -a sha256 -cy end ^
         -sky signature ^
         -ic MyCA.cer -iv MyCA.pvk ^
         -sv MySPC.pvk MySPC.cer

It is pretty much the same as above, but we're providing an issuer key and certificate (the -ic and -iv switches).

We'll also want to convert the certificate and key into a PFX file:

pvk2pfx -pvk MySPC.pvk -spc MySPC.cer -pfx MySPC.pfx

If you want to protect the PFX file, add the -po switch, otherwise PVK2PFX creates a PFX file with no passphrase.

Using the certificate for signing code

signtool sign /v /f MySPC.pfx ^
              /t http://timestamp.url MyExecutable.exe

(See why timestamps may matter)

If you import the PFX file into the certificate store (you can use PVKIMPRT or the MMC snapin), you can sign code as follows:

signtool sign /v /n "Me" /s SPC ^
              /t http://timestamp.url MyExecutable.exe

Some possible timestamp URLs for signtool /t are:

  • http://timestamp.verisign.com/scripts/timstamp.dll
  • http://timestamp.globalsign.com/scripts/timstamp.dll
  • http://timestamp.comodoca.com/authenticode

Full Microsoft documentation

Downloads

For those who are not .NET developers, you will need a copy of the Windows SDK and .NET framework. A current link is available here: SDK & .NET (which installs makecert in C:\Program Files\Microsoft SDKs\Windows\v7.1). Your mileage may vary.

MakeCert is available from the Visual Studio Command Prompt. Visual Studio 2015 does have it, and it can be launched from the Start Menu in Windows 7 under "Developer Command Prompt for VS 2015" or "VS2015 x64 Native Tools Command Prompt" (probably all of them in the same folder).

Maven project.build.directory

It points to your top level output directory (which by default is target):

https://web.archive.org/web/20150527103929/http://docs.codehaus.org/display/MAVENUSER/MavenPropertiesGuide

EDIT: As has been pointed out, Codehaus is now sadly defunct. You can find details about these properties from Sonatype here:

http://books.sonatype.com/mvnref-book/reference/resource-filtering-sect-properties.html#resource-filtering-sect-project-properties

If you are ever trying to reference output directories in Maven, you should never use a literal value like target/classes. Instead you should use property references to refer to these directories.

    project.build.sourceDirectory
    project.build.scriptSourceDirectory
    project.build.testSourceDirectory
    project.build.outputDirectory
    project.build.testOutputDirectory
    project.build.directory

sourceDirectory, scriptSourceDirectory, and testSourceDirectory provide access to the source directories for the project. outputDirectory and testOutputDirectory provide access to the directories where Maven is going to put bytecode or other build output. directory refers to the directory which contains all of these output directories.

Django URL Redirect

You can try the Class Based View called RedirectView

from django.views.generic.base import RedirectView

urlpatterns = patterns('',
    url(r'^$', 'macmonster.views.home'),
    #url(r'^macmon_home$', 'macmonster.views.home'),
    url(r'^macmon_output/$', 'macmonster.views.output'),
    url(r'^macmon_about/$', 'macmonster.views.about'),
    url(r'^.*$', RedirectView.as_view(url='<url_to_home_view>', permanent=False), name='index')
)

Notice how as url in the <url_to_home_view> you need to actually specify the url.

permanent=False will return HTTP 302, while permanent=True will return HTTP 301.

Alternatively you can use django.shortcuts.redirect

Update for Django 2+ versions

With Django 2+, url() is deprecated and replaced by re_path(). Usage is exactly the same as url() with regular expressions. For replacements without the need of regular expression, use path().

from django.urls import re_path

re_path(r'^.*$', RedirectView.as_view(url='<url_to_home_view>', permanent=False), name='index')

Getting activity from context in android

This method should be helpful..!

public Activity getActivityByContext(Context context){

if(context == null){
    return null;
    }

else if((context instanceof ContextWrapper) && (context instanceof Activity)){
        return (Activity) context;
    }

else if(context instanceof ContextWrapper){
        return getActivity(((ContextWrapper) context).getBaseContext());
    }

return null;

    }

I hope this helps.. Merry coding!

How to delete all instances of a character in a string in python?

# s1 == source string
# char == find this character
# repl == replace with this character
def findreplace(s1, char, repl):
    s1 = s1.replace(char, repl)
    return s1

# find each 'i' in the string and replace with a 'u'
print findreplace('it is icy', 'i', 'u')
# output
''' ut us ucy '''

Write / add data in JSON file using Node.js

you should read the file, every time you want to add a new property to the json, and then add the the new properties

var fs = require('fs');
fs.readFile('data.json',function(err,content){
  if(err) throw err;
  var parseJson = JSON.parse(content);
  for (i=0; i <11 ; i++){
   parseJson.table.push({id:i, square:i*i})
  }
  fs.writeFile('data.json',JSON.stringify(parseJson),function(err){
    if(err) throw err;
  })
})

Run ssh and immediately execute command

You can use the LocalCommand command-line option if the PermitLocalCommand option is enabled:

ssh username@hostname -o LocalCommand="tmux list-sessions"

For more details about the available options, see the ssh_config man page.

IntelliJ IDEA "cannot resolve symbol" and "cannot resolve method"

I was facing the same problem when import projects into IntelliJ.

for in my case first, check SDK details and check you have configured JDK correctly or not.

Go to File-> Project Structure-> platform Settings-> SDKs

Check your JDK is correct or not.

enter image description here

Next, I Removed project from IntelliJ and delete all IntelliJ and IDE related files and folder from the project folder (.idea, .settings, .classpath, dependency-reduced-pom). Also, delete the target folder and re-import the project.

The above solution worked in my case.

Finding the number of days between two dates

function get_daydiff($end_date,$today)
{
    if($today=='')
    {
        $today=date('Y-m-d');
    }
    $str = floor(strtotime($end_date)/(60*60*24)) - floor(strtotime($today)/(60*60*24));
    return $str;
}
$d1 = "2018-12-31";
$d2 = "2018-06-06";
echo get_daydiff($d1, $d2);

How does one reorder columns in a data frame?

# reorder by column name
data <- data[c("A", "B", "C")]

#reorder by column index
data <- data[c(1,3,2)]

Convert generic List/Enumerable to DataTable?

If you want to use reflection and set columns order/ include only some columns/ Exclude some columns try this:

        private static DataTable ConvertToDataTable<T>(IList<T> data, string[] fieldsToInclude = null,
string[] fieldsToExclude = null)
    {
        PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(typeof(T));
        DataTable table = new DataTable();
        foreach (PropertyDescriptor prop in properties)
        {
            if ((fieldsToInclude != null && !fieldsToInclude.Contains(prop.Name)) ||
                (fieldsToExclude != null && fieldsToExclude.Contains(prop.Name)))
                continue;
            table.Columns.Add(prop.Name, Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType);
        }

        foreach (T item in data)
        {
            var atLeastOnePropertyExists = false;
            DataRow row = table.NewRow();
            foreach (PropertyDescriptor prop in properties)
            {

                if ((fieldsToInclude != null && !fieldsToInclude.Contains(prop.Name)) ||
(fieldsToExclude != null && fieldsToExclude.Contains(prop.Name)))
                    continue;

                row[prop.Name] = prop.GetValue(item) ?? DBNull.Value;
                atLeastOnePropertyExists = true;
            }

            if(atLeastOnePropertyExists) table.Rows.Add(row);
        }


        if (fieldsToInclude != null)
            SetColumnsOrder(table, fieldsToInclude);

        return table;

    }

    private static void SetColumnsOrder(DataTable table, params String[] columnNames)
    {
        int columnIndex = 0;
        foreach (var columnName in columnNames)
        {
            table.Columns[columnName].SetOrdinal(columnIndex);
            columnIndex++;
        }
    }

jQuery change event on dropdown

The html

<select id="drop"  name="company" class="company btn btn-outline   dropdown-toggle" >
   <option value="demo1">Group Medical</option>
   <option value="demo">Motor Insurance</option>
</select>

Script.js

$("#drop").change(function () {                            
   var category= $('select[name=company]').val() // Here we can get the value of selected item
   alert(category); 
});

Is PowerShell ready to replace my Cygwin shell on Windows?

As my recent experiments led me into depths of PowerShell and .NET calls, I must say that PowerShell can replace Cygwin and Unix shell.

I'm not sure about Perl, but since both PowerShell and Perl are Turing complete as programming languages, I give this as a yes to replacing Perl too.

One thing that PowerShell has above Cygwin and ordinary Bash under *nix, is its ability to perform sandboxed DLL calls, manipulating the operating system via direct API calls, WMI methods and even COM objects. How about launching Internet Explorer via code, then doing whatever you want with its displayed document, effectively emulating a back-end for a Web server?

How about gathering data from SQL servers and other data providers, parse them and export as CSV, mail messages, text and actually any kind of existing and non-existing file formats? (With proper skills of creating a valid file out of data received, of course, but CSV are readily available).

And there is an extra security available via signed cmdlets and scripts, group policies, and execution policies that help prevent malicious code from running on your system even if you run them as administrator.

About what commands are implemented - the answer by Richard lists them and PowerShell's capability of emulating their functionality already.

About whether PowerShell is strong to warrant switching over - this is more a matter of personal preference, although as more and more Windows services are providing PowerShell cmdlets to control them, not using PowerShell with these services present is considered a hindrance. (Hyper-V server is the primary such service, and it also provides the ability to do more with PowerShell cmdlets than with GUI!)

Probably this answer is five years late, but still, if someone performs administrative tasks or general scripting of various stuff on Windows, they should definitely try harnessing PowerShell for their purposes.

How can you print a variable name in python?

For the revised question of how to read in configuration parameters, I'd strongly recommend saving yourself some time and effort and use ConfigParser or (my preferred tool) ConfigObj.

They can do everything you need, they're easy to use, and someone else has already worried about how to get them to work properly!

CONVERT Image url to Base64

Here's the Typescript version of Abubakar Ahmad's answer

function imageTo64(
  url: string, 
  callback: (path64: string | ArrayBuffer) => void
): void {
  const xhr = new XMLHttpRequest();
  xhr.open('GET', url);
  xhr.responseType = 'blob';
  xhr.send();

  xhr.onload = (): void => {
    const reader = new FileReader();
    reader.readAsDataURL(xhr.response);
    reader.onloadend = (): void => callback(reader.result);
  }
}

Creating an Arraylist of Objects

ArrayList<Matrices> list = new ArrayList<Matrices>();
list.add( new Matrices(1,1,10) );
list.add( new Matrices(1,2,20) );

Angular ng-if="" with multiple arguments

Just to clarify, be aware bracket placement is important!

These can be added to any HTML tags... span, div, table, p, tr, td etc.

AngularJS

ng-if="check1 && !check2" -- AND NOT
ng-if="check1 || check2" -- OR
ng-if="(check1 || check2) && check3" -- AND/OR - Make sure to use brackets

Angular2+

*ngIf="check1 && !check2" -- AND NOT
*ngIf="check1 || check2" -- OR
*ngIf="(check1 || check2) && check3" -- AND/OR - Make sure to use brackets

It's best practice not to do calculations directly within ngIfs, so assign the variables within your component, and do any logic there.

boolean check1 = Your conditional check here...
...

PHP how to get value from array if key is in a variable

It should work the way you intended.

$array = array('value-0', 'value-1', 'value-2', 'value-3', 'value-4', 'value-5' /* … */);
$key = 4;
$value = $array[$key];
echo $value; // value-4

But maybe there is no element with the key 4. If you want to get the fiveth item no matter what key it has, you can use array_slice:

$value = array_slice($array, 4, 1);

Rails 3 execute custom sql query without a model

Maybe try this:

ActiveRecord::Base.establish_connection(...)
ActiveRecord::Base.connection.execute(...)

Export pictures from excel file into jpg using VBA

If i remember correctly, you need to use the "Shapes" property of your sheet.

Each Shape object has a TopLeftCell and BottomRightCell attributes that tell you the position of the image.

Here's a piece of code i used a while ago, roughly adapted to your needs. I don't remember the specifics about all those ChartObjects and whatnot, but here it is:

For Each oShape In ActiveSheet.Shapes
    strImageName = ActiveSheet.Cells(oShape.TopLeftCell.Row, 1).Value
    oShape.Select
    'Picture format initialization
    Selection.ShapeRange.PictureFormat.Contrast = 0.5: Selection.ShapeRange.PictureFormat.Brightness = 0.5: Selection.ShapeRange.PictureFormat.ColorType = msoPictureAutomatic: Selection.ShapeRange.PictureFormat.TransparentBackground = msoFalse: Selection.ShapeRange.Fill.Visible = msoFalse: Selection.ShapeRange.Line.Visible = msoFalse: Selection.ShapeRange.Rotation = 0#: Selection.ShapeRange.PictureFormat.CropLeft = 0#: Selection.ShapeRange.PictureFormat.CropRight = 0#: Selection.ShapeRange.PictureFormat.CropTop = 0#: Selection.ShapeRange.PictureFormat.CropBottom = 0#: Selection.ShapeRange.ScaleHeight 1#, msoTrue, msoScaleFromTopLeft: Selection.ShapeRange.ScaleWidth 1#, msoTrue, msoScaleFromTopLeft
    '/Picture format initialization
    Application.Selection.CopyPicture
    Set oDia = ActiveSheet.ChartObjects.Add(0, 0, oShape.Width, oShape.Height)
    Set oChartArea = oDia.Chart
    oDia.Activate
    With oChartArea
        .ChartArea.Select
        .Paste
        .Export ("H:\Webshop_Zpider\Strukturbildene\" & strImageName & ".jpg")
    End With
    oDia.Delete 'oChartArea.Delete
Next

Does JSON syntax allow duplicate keys in an object?

The JSON spec says this:

An object is an unordered set of name/value pairs.

The important part here is "unordered": it implies uniqueness of keys, because the only thing you can use to refer to a specific pair is its key.

In addition, most JSON libs will deserialize JSON objects to hash maps/dictionaries, where keys are guaranteed unique. What happens when you deserialize a JSON object with duplicate keys depends on the library: in most cases, you'll either get an error, or only the last value for each duplicate key will be taken into account.

For example, in Python, json.loads('{"a": 1, "a": 2}') returns {"a": 2}.

How to get distinct values from an array of objects in JavaScript?

I know my code is little length and little time complexity but it's understandable so I tried this way.

I'm trying to develop prototype based function here and code also change.

Here,Distinct is my own prototype function.

_x000D_
_x000D_
<script>_x000D_
  var array = [{_x000D_
      "name": "Joe",_x000D_
      "age": 17_x000D_
    },_x000D_
    {_x000D_
      "name": "Bob",_x000D_
      "age": 17_x000D_
    },_x000D_
    {_x000D_
      "name": "Carl",_x000D_
      "age": 35_x000D_
    }_x000D_
  ]_x000D_
_x000D_
  Array.prototype.Distinct = () => {_x000D_
    var output = [];_x000D_
    for (let i = 0; i < array.length; i++) {_x000D_
      let flag = true;_x000D_
      for (let j = 0; j < output.length; j++) {_x000D_
        if (array[i].age == output[j]) {_x000D_
          flag = false;_x000D_
          break;_x000D_
        }_x000D_
      }_x000D_
      if (flag)_x000D_
        output.push(array[i].age);_x000D_
    }_x000D_
    return output;_x000D_
  }_x000D_
  //Distinct is my own function_x000D_
  console.log(array.Distinct());_x000D_
</script>
_x000D_
_x000D_
_x000D_

Get Wordpress Category from Single Post

For the lazy and the learning, to put it into your theme, Rfvgyhn's full code

<?php $category = get_the_category();
$firstCategory = $category[0]->cat_name; echo $firstCategory;?>

Calling a method inside another method in same class

It is just an overload. The add method is from the ArrayList class. Look that Staff inherits from it.

Using ListView : How to add a header view?

You simply can't use View as a Header of ListView.

Because the view which is being passed in has to be inflated.

Look at my answer at Android ListView addHeaderView() nullPointerException for predefined Views for more info.

EDIT:

Look at this tutorial Android ListView and ListActivity - Tutorial .

EDIT 2: This link is broken Android ListActivity with a header or footer

Getting specified Node values from XML document

Just like you do for getting something from the CNode you also need to do for the ANode

XmlNodeList xnList = xml.SelectNodes("/Element[@*]");
foreach (XmlNode xn in xnList)
{
  XmlNode anode = xn.SelectSingleNode("ANode");
    if (anode!= null)
    {
        string id = anode["ID"].InnerText;
        string date = anode["Date"].InnerText;
        XmlNodeList CNodes = xn.SelectNodes("ANode/BNode/CNode");
        foreach (XmlNode node in CNodes)
        {
         XmlNode example = node.SelectSingleNode("Example");
         if (example != null)
         {
            string na = example["Name"].InnerText;
            string no = example["NO"].InnerText;
         }
        }
    }
}

403 Access Denied on Tomcat 8 Manager App without prompting for user/password

  1. Go and Check if a user is created or not if no please create a user by opening a file in /apache-tomcat-9.0.20/tomcat-users.xml add a line into it

    <user username="tomcat" password="tomcat" roles="admin-gui,manager-gui,manager-script" />

  2. Goto /apache-tomcat-9.0.20/webapps/manager/META-INF/ open context.xml comment everything in context tag example:

<Context antiResourceLocking="false" privileged="true" >
     <!--Valve className="org.apache.catalina.valves.RemoteAddrValve"
            allow="127\.\d+\.\d+\.\d+|::1|0:0:0:0:0:0:0:1" /-->
   </Context>

How do I access my webcam in Python?

John Montgomery's, answer is great, but at least on Windows, it is missing the line

vc.release()

before

cv2.destroyWindow("preview")

Without it, the camera resource is locked, and can not be captured again before the python console is killed.

What is JSONP, and why was it created?

TL;DR

JSONP is an old trick invented to bypass the security restriction that forbids us to get JSON data that is in a different website (a different origin1) than the one we are navigating in.

The trick works by using a <script> tag that asks for the JSON from that place, e.g.: { "user":"Smith" }, but wrapped in a function, the actual JSONP ("JSON with Padding"):

peopleDataJSONP({"user":"Smith"})

Receiving it in this form enables us to use the data within our peopleDataJSONP function. JSONP is a bad practice and not needed anymore, don't use it (read below).


The problem

Say we want to use on ourweb.com some JSON data (or any raw data really) hosted at anotherweb.com. If we were to use GET request (think XMLHttpRequest, or fetch call, $.ajax, etc.), our browser would tell us it's not allowed with this ugly error:

Chrome CORS console error

How to get the data we want? Well, <script> tags are not subjected to this whole server (origin1) restriction! That's why we can load a library like jQuery or Google Maps from any server, such as a CDN, without any errors.

Here's the important point: if you think about it, those libraries are actual, runnable JS code (usually a massive function with all the logic inside). But raw data? JSON data is not code. There's nothing to run; it's just plain text.

Therefore, there's no way to handle or manipulate our precious data. The browser will download the data pointed at by our <script> tag and when processing it'll rightfully complain:

wtf is this {"user":"Smith"} crap we loaded? It's not code. I can't compute, syntax error!


The JSONP hack

The old/hacky way to utilize that data? If we could make plain text somehow runnable, we could grab it on runtime. So we need anotherweb.com to send it with some logic, so when it's loaded, your code in the browser will be able to use said data. We need two things: 1) to get the data in a way that it can be run, and 2) write some code in the client so that when the data runs, this code is called and we get to use the data.

For 1) we ask the foreign server to send us the JSON data inside a JS function. The data itself is set up as that function's input. It looks like this:

peopleDataJSONP({"user":"Smith"})

which makes it JS code our browser will parse and run without complaining! Exactly like it does with the jQuery library. To receive the data like that, the client "asks" the JSONP-friendly server for it, usually done like this:

<script src="https://anotherweb.com/api/data-from-people.json?myCallback=peopleDataJSONP"></script>

As per 2), since our browser will receive the JSONP with that function name, we need a function with the same name in our code, like this:

function peopleDataJSONP(data){
  alert(data.user); // "Smith"
}

The browser will download the JSONP and run it, which calls our function, where the argument data will be the JSON data from anotherweb.com. We can now do with our data whatever we want to.


Don't use JSONP, use CORS

JSONP is a cross-site hack with a few downsides:

  • We can only perform GET requests
  • Since it's a GET request triggered by a simple script tag, we don't get helpful errors or progress info
  • There are also some security concerns, like running in your client JS code that could be changed to a malicious payload
  • It only solves the problem with JSON data, but Same-Origin security policy applies to other data (WebFonts, images/video drawn with drawImage()...)
  • It's not very elegant nor readable.

The takeaway is that there's no need to use it nowadays.

You should read about CORS here, but the gist of it is:

Cross-Origin Resource Sharing (CORS) is a mechanism that uses additional HTTP headers to tell browsers to give a web application running at one origin, access to selected resources from a different origin. A web application executes a cross-origin HTTP request when it requests a resource that has a different origin (domain, protocol, or port) from its own.



  1. origin is defined by 3 things: protocol, port, and host. So, for example, https://web.com is a different origin than http://web.com (different protocol) and https://web.com:8081 (different port) and obviously https://thatotherweb.net (different host)

How to set the matplotlib figure default size in ipython notebook?

Just for completeness, this also works

from IPython.core.pylabtools import figsize
figsize(14, 7)

It is a wrapper aroung the rcParams solution

How can I disable notices and warnings in PHP within the .htaccess file?

If you are in a shared hosting plan that doesn't have PHP installed as a module you will get a 500 server error when adding those flags to the .htaccess file.

But you can add the line

ini_set('display_errors','off');

on top of your .php file and it should work without any errors.

Docker error: invalid reference format: repository name must be lowercase

A "reference" in docker is a pointer to an image. It may be an image name, an image ID, include a registry server in the name, use a sha256 tag to pin the image, and anything else that can be used to point to the image you want to run.

The invalid reference format error message means docker cannot convert the string you've provided to an image. This may be an invalid name, or it may be from a parsing error earlier in the docker run command line if that's how you run the image. With a compose file, if you expand a variable in the image name, that variable may not be expanding correctly.

With the docker run command line, this is often the result in not quoting parameters with spaces, and mistaking the order of the command line. The command line is ordered as:

docker ${args_to_docker} run ${args_to_run} image_ref ${cmd_to_exec}

The most common error in passing args to the run is a volume mapping expanding a path name that includes a space in it, and not quoting the path or escaping the space. E.g.

docker run -v $(pwd):/data image_ref

And the fix is as easy as:

docker run -v "$(pwd):/data" image_ref

Jenkins: Failed to connect to repository

I had the exact same problem. The way I solved it on Mac is this:

  1. Switch to jenkins user (sudo -iu jenkins)
  2. Run: ssh-keygen (Note - You are creating ssh key pairs for jenkins user now. You should see something like this : Enter file in which to save the key (/Users/Shared/Jenkins/.ssh/id_rsa):
  3. Keep pressing Enter for default value till end
  4. Run the command showing in the Jenkins error message, on your teminal (eg : "git ls-remote -h [email protected]:adolfosrs/jenkins-test.git HEAD")
  5. You will be asked if you want to continue. Say yes
  6. The Github repo will be added to your known_hosts file in : /Users/Shared/Jenkins/.ssh/
  7. Go back to Jenkins portal and try your Github SSH url
  8. It should work. Good Luck

Send value of submit button when form gets posted

You could use something like this to give your button a value:

<?php
if (isset($_POST['submit'])) {
  $aSubmitVal = array_keys($_POST['submit'])[0];
  echo 'The button value is: ' . $aSubmitVal;
}
?>
<form action="/" method="post">
  <input id="someId" type="submit" name="submit[SomeValue]" value="Button name">
</form>

This will give you the string "SomeValue" as a result

https://i.imgur.com/28gr7Uy.gif

ip address validation in python using regex

Use anchors instead:

aa=re.match(r"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$",ip)

These make sure that the start and end of the string are matched at the start and end of the regex. (well, technically, you don't need the starting ^ anchor because it's implicit in the .match() method).

Then, check if the regex did in fact match before trying to access its results:

if aa:
    ip = aa.group()

Of course, this is not a good approach for validating IP addresses (check out gnibbler's answer for a proper method). However, regexes can be useful for detecting IP addresses in a larger string:

ip_candidates = re.findall(r"\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b", ip)

Here, the \b word boundary anchors make sure that the digits don't exceed 3 for each segment.

How to make flutter app responsive according to different screen size?

  padding: EdgeInsets.only(
      left: 4.0,
      right: ResponsiveWidget.isSmallScreen(context) ? 4: 74, //Check for screen type
      top: 10,
      bottom: 40),

This is fine by Google's recommendation but may be not perfect.

JQuery select2 set default value from an option in list?

$("#id").select2("val", null); //this will not work..you can try

You should actually do this...intialise and then set the value..well this is also the way it worked for me.

$("#id").select2().select2("val", null);
$("#id").select2().select2("val", 'oneofthevaluehere');

Get current URL/URI without some of $_GET variables

Yii 1

Yii::app()->request->url

For Yii2:

Yii::$app->request->url

Java double comparison epsilon

Floating point numbers only have so many significant digits, but they can go much higher. If your app will ever handle large numbers, you will notice the epsilon value should be different.

0.001+0.001 = 0.002 BUT 12,345,678,900,000,000,000,000+1=12,345,678,900,000,000,000,000 if you are using floating point and double. It's not a good representation of money, unless you are damn sure you'll never handle more than a million dollars in this system.

Get month name from Date

If you don't want to use an external library, or store an array of month names, or if the ECMAScript Internationalization API is not good enough because of browser compatibility you can always do it the old-fashioned way by extracting the info from the date output:

var now = new Date();
var monthAbbrvName = now.toDateString().substring(4, 7);

This would give you the abbreviated month name, e.g. Oct. I believe the date will come in all sorts of formats depending on the initialization and your locale so take a look at what toDateString() returns and recalculate your substring() values based on that.

How to convert String to DOM Document object in java?

you can try

DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader("<root><node1></node1></root>"));

Document doc = db.parse(is);

refer this http://www.java2s.com/Code/Java/XML/ParseanXMLstringUsingDOMandaStringReader.htm

Sending the bearer token with axios

The second parameter of axios.post is data (not config). config is the third parameter. Please see this for details: https://github.com/mzabriskie/axios#axiosposturl-data-config

Open text file and program shortcut in a Windows batch file

Its very simple, 1)Just go on directory where the file us stored 2)then enter command i.e. type filename.file_extention e.g type MyFile.tx

WAMP shows error 'MSVCR100.dll' is missing when install

I encountered this problem when my operating system was in French, and I was installing Wampserver in English.

I am pretty sure that Microsoft Redistributable packages were installed since I was already working with Visual Studio. I think the issue may have been because of changes in path names with different languages. However, when I installed wampserver in French, everything worked perfectly.

How to prevent page scrolling when scrolling a DIV element?

If you don't care about the compatibility with older IE versions (< 8), you could make a custom jQuery plugin and then call it on the overflowing element.

This solution has an advantage over the one Šime Vidas proposed, as it doesn't overwrite the scrolling behavior - it just blocks it when appropriate.

$.fn.isolatedScroll = function() {
    this.bind('mousewheel DOMMouseScroll', function (e) {
        var delta = e.wheelDelta || (e.originalEvent && e.originalEvent.wheelDelta) || -e.detail,
            bottomOverflow = this.scrollTop + $(this).outerHeight() - this.scrollHeight >= 0,
            topOverflow = this.scrollTop <= 0;

        if ((delta < 0 && bottomOverflow) || (delta > 0 && topOverflow)) {
            e.preventDefault();
        }
    });
    return this;
};

$('.scrollable').isolatedScroll();

Allow only numbers to be typed in a textbox

You also can use some HTML5 attributes, some browsers might already take advantage of them (type="number" min="0").

Whatever you do, remember to re-check your inputs on the server side: you can never assume the client-side validation has been performed.

How to embed image or picture in jupyter notebook, either from a local machine or from a web resource?

Here's how you can do it with Markdown:

![Image of Yaktocat](https://octodex.github.com/images/yaktocat.png)

View the change history of a file using Git versioning

You can use vscode with GitLens, it's a very powerful tool. After installed GitLens, go to GitLens tab, select FILE HISTORY and you can browse it.

enter image description here

Installing Numpy on 64bit Windows 7 with Python 2.7.3

Try the (unofficial) binaries in this site:

http://www.lfd.uci.edu/~gohlke/pythonlibs/#numpy

You can get the newest numpy x64 with or without Intel MKL libs for Python 2.7 or Python 3.

Understanding timedelta

why do I have to pass seconds = uptime to timedelta

Because timedelta objects can be passed seconds, milliseconds, days, etc... so you need to specify what are you passing in (this is why you use the explicit key). Typecasting to int is superfluous as they could also accept floats.

and why does the string casting works so nicely that I get HH:MM:SS ?

It's not the typecasting that formats, is the internal __str__ method of the object. In fact you will achieve the same result if you write:

print datetime.timedelta(seconds=int(uptime))

Remove all multiple spaces in Javascript and replace with single space

You can also replace without a regular expression.

while(str.indexOf('  ')!=-1)str.replace('  ',' ');

How to maintain state after a page refresh in React.js?

I consider state to be for view only information and data that should persist beyond the view state is better stored as props. URL params are useful when you want to be able to link to a page or share the URL deep in to the app but otherwise clutter the address bar.

Take a look at Redux-Persist (if you're using redux) https://github.com/rt2zz/redux-persist

IPython/Jupyter Problems saving notebook as PDF

If you are using sagemath cloud version, you can simply go to the left corner,
select File --> Download as --> Pdf via LaTeX (.pdf)
Check the screenshot if you want.

Screenshot Convert ipynb to pdf

If it dosn't work for any reason, you can try another way.
select File --> Print Preview and then on the preview
right click --> Print and then select save as pdf.

Convert NaN to 0 in javascript

Methods that use isNaN do not work if you're trying to use parseInt, for example:

parseInt("abc"); // NaN
parseInt(""); // NaN
parseInt("14px"); // 14

But in the second case isNaN produces false (i.e. the null string is a number)

n="abc"; isNaN(n) ? 0 : parseInt(n); // 0
n=""; isNaN(n) ? 0: parseInt(n); // NaN
n="14px"; isNaN(n) ? 0 : parseInt(n); // 14

In summary, the null string is considered a valid number by isNaN but not by parseInt. Verified with Safari, Firefox and Chrome on OSX Mojave.

ASP.Net MVC: How to display a byte array image from model

This worked for me

<img src="data:image;base64,@System.Convert.ToBase64String(Model.CategoryPicture.Content)" width="80" height="80"/>     

How can I explicitly free memory in Python?

You can't explicitly free memory. What you need to do is to make sure you don't keep references to objects. They will then be garbage collected, freeing the memory.

In your case, when you need large lists, you typically need to reorganize the code, typically using generators/iterators instead. That way you don't need to have the large lists in memory at all.

http://www.prasannatech.net/2009/07/introduction-python-generators.html

How to get a index value from foreach loop in jstl

<a onclick="getCategoryIndex(${myIndex.index})" href="#">${categoryName}</a>

above line was giving me an error. So I wrote down in below way which is working fine for me.

<a onclick="getCategoryIndex('<c:out value="${myIndex.index}"/>')" href="#">${categoryName}</a>

Maybe someone else might get same error. Look at this guys!

How to create an AVD for Android 4.0

This site Android Create AVD shows you how to install the latest version of the Android SDK and AVD version 4 in Eclipse with video and screenshots if you're still stuck?

Adding a JAR to an Eclipse Java library

As of Helios Service Release 2, there is no longer support for JAR files.You can add them, but Eclipse will not recognize them as libraries, therefore you can only "import" but can never use.

c# datatable insert column at position 0

    //Example to define how to do :

    DataTable dt = new DataTable();   

    dt.Columns.Add("ID");
    dt.Columns.Add("FirstName");
    dt.Columns.Add("LastName");
    dt.Columns.Add("Address");
    dt.Columns.Add("City");
           //  The table structure is:
            //ID    FirstName   LastName    Address     City

       //Now we want to add a PhoneNo column after the LastName column. For this we use the                               
             //SetOrdinal function, as iin:
        dt.Columns.Add("PhoneNo").SetOrdinal(3);

            //3 is the position number and positions start from 0.`enter code here`

               //Now the table structure will be:
              // ID      FirstName   LastName    PhoneNo    Address     City

Caused by: java.security.UnrecoverableKeyException: Cannot recover key

In order to not have the Cannot recover key exception, I had to apply the Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files to the installation of Java that was running my application. Version 8 of those files can be found here or the latest version should be listed on this page. The download includes a file that explains how to apply the policy files.


Since JDK 8u151 it isn't necessary to add policy files. Instead the JCE jurisdiction policy files are controlled by a Security property called crypto.policy. Setting that to unlimited with allow unlimited cryptography to be used by the JDK. As the release notes linked to above state, it can be set by Security.setProperty() or via the java.security file. The java.security file could also be appended to by adding -Djava.security.properties=my_security.properties to the command to start the program as detailed here.


Since JDK 8u161 unlimited cryptography is enabled by default.

how to view the contents of a .pem certificate

Use the -printcert command like this:

keytool -printcert -file certificate.pem

ORA-12528: TNS Listener: all appropriate instances are blocking new connections. Instance "CLRExtProc", status UNKNOWN

set ORACLE_SID=<YOUR_SID>
sqlplus "/as sysdba"
alter system disable restricted session;

or maybe

shutdown abort;

or maybe

lsnrctl stop

lsnrctl start

Best way to convert an ArrayList to a string

Android has a TextUtil class you can use http://developer.android.com/reference/android/text/TextUtils.html

String implode = TextUtils.join("\t", list);

Loop Through Each HTML Table Column and Get the Data using jQuery

When you create your table, put your td with class = "suma"

$(function(){   

   //funcion suma todo

   var sum = 0;
   $('.suma').each(function(x,y){
       sum += parseInt($(this).text());                                   
   })           
   $('#lblTotal').text(sum);   

   // funcion suma por check                                           

    $( "input:checkbox").change(function(){
    if($(this).is(':checked')){     
        $(this).parent().parent().find('td:last').addClass('suma2');
   }else{       
        $(this).parent().parent().find('td:last').removeClass('suma2');
   }    
   suma2Total();                                                           
   })                                                      

   function suma2Total(){
      var sum2 = 0;
      $('.suma2').each(function(x,y){
        sum2 += parseInt($(this).text());       
      })
      $('#lblTotal2').text(sum2);                                              
   }                                                                      
});

Ejemplo completo

How to set fake GPS location on IOS real device

you can do it on real device by run device in Debug mode

Click Debug->Simulate Location -> add .gpx file for your location during run time

How can I check whether a radio button is selected with JavaScript?

An example:

if (!checkRadioArray(document.ExamEntry.level)) { 
    msg+="What is your level of entry? \n"; 
    document.getElementById('entry').style.color="red"; 
    result = false; 
} 

if(msg==""){ 
    return result;  
} 
else{ 
    alert(msg) 
    return result;
} 

function Radio() { 
    var level = radio.value; 
    alert("Your level is: " + level + " \nIf this is not the level your taking then please choose another.") 
} 

function checkRadioArray(radioButtons) { 
    for(var r=0;r < radioButtons.length; r++) { 
        if (radioButtons[r].checked) { 
            return true; 
        } 
    } 
    return false; 
} 

Converting a string to JSON object

var Data=[{"id": "name2", "label": "Quantity"}]

Pass the string variable into Json parse :

Objdata= Json.parse(Data);

Force hide address bar in Chrome on Android

Check this has everything you need

http://www.html5rocks.com/en/mobile/fullscreen/

The Chrome team has recently implemented a feature that tells the browser to launch the page fullscreen when the user has added it to the home screen. It is similar to the iOS Safari model.

<meta name="mobile-web-app-capable" content="yes">

width:auto for <input> fields

It may not be exactly what you want, but my workaround is to apply the autowidth styling to a wrapper div - then set your input to 100%.

How to update (append to) an href in jquery?

var _href = $("a.directions-link").attr("href");
$("a.directions-link").attr("href", _href + '&saddr=50.1234567,-50.03452');

To loop with each()

$("a.directions-link").each(function() {
   var $this = $(this);       
   var _href = $this.attr("href"); 
   $this.attr("href", _href + '&saddr=50.1234567,-50.03452');
});

Check box size change with CSS

input fields can be styled as you wish. So instead of zoom, you could have

input[type="checkbox"]{
  width: 30px; /*Desired width*/
  height: 30px; /*Desired height*/
}

EDIT:

You would have to add extra rules like this:

input[type="checkbox"]{
  width: 30px; /*Desired width*/
  height: 30px; /*Desired height*/
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

Check this fiddle http://jsfiddle.net/p36tqqyq/1/

Convert UIImage to NSData and convert back to UIImage in Swift?

UIImage(data:imageData,scale:1.0) presuming the image's scale is 1.

In swift 4.2, use below code for get Data().

image.pngData()

Get the first element of each tuple in a list in Python

You can use list comprehension:

res_list = [i[0] for i in rows]

This should make the trick

RecyclerView - Get view at particular position

You can simply use "findViewHolderForAdapterPosition" method of recycler view and you will get a viewHolder object from that then typecast that viewholder into your adapter viewholder so you can directly access your viewholder's views

following is the sample code for kotlin

 val viewHolder = recyclerView.findViewHolderForAdapterPosition(position)
 val textview=(viewHolder as YourViewHolder).yourTextView

How to send data with angularjs $http.delete() request?

$http.delete method doesn't accept request body. You can try this workaround :

$http( angular.merge({}, config || {}, {
    method  : 'delete',
    url     : _url,
    data    : _data
}));

where in config you can pass config data like headers etc.

Controlling fps with requestAnimationFrame?

How to throttle requestAnimationFrame to a specific frame rate

Demo throttling at 5 FPS: http://jsfiddle.net/m1erickson/CtsY3/

This method works by testing the elapsed time since executing the last frame loop.

Your drawing code executes only when your specified FPS interval has elapsed.

The first part of the code sets some variables used to calculate elapsed time.

var stop = false;
var frameCount = 0;
var $results = $("#results");
var fps, fpsInterval, startTime, now, then, elapsed;


// initialize the timer variables and start the animation

function startAnimating(fps) {
    fpsInterval = 1000 / fps;
    then = Date.now();
    startTime = then;
    animate();
}

And this code is the actual requestAnimationFrame loop which draws at your specified FPS.

// the animation loop calculates time elapsed since the last loop
// and only draws if your specified fps interval is achieved

function animate() {

    // request another frame

    requestAnimationFrame(animate);

    // calc elapsed time since last loop

    now = Date.now();
    elapsed = now - then;

    // if enough time has elapsed, draw the next frame

    if (elapsed > fpsInterval) {

        // Get ready for next frame by setting then=now, but also adjust for your
        // specified fpsInterval not being a multiple of RAF's interval (16.7ms)
        then = now - (elapsed % fpsInterval);

        // Put your drawing code here

    }
}

Can I compile all .cpp files in src/ to .o's in obj/, then link to binary in ./?

Wildcard works for me also, but I'd like to give a side note for those using directory variables. Always use slash for folder tree (not backslash), otherwise it will fail:

BASEDIR = ../..
SRCDIR = $(BASEDIR)/src
INSTALLDIR = $(BASEDIR)/lib

MODULES = $(wildcard $(SRCDIR)/*.cpp)
OBJS = $(wildcard *.o)

Creating a LINQ select from multiple tables

If you don't want to use anonymous types b/c let's say you're passing the object to another method, you can use the LoadWith load option to load associated data. It requires that your tables are associated either through foreign keys or in your Linq-to-SQL dbml model.

db.DeferredLoadingEnabled = false;
DataLoadOptions dlo = new DataLoadOptions();
dlo.LoadWith<ObjectPermissions>(op => op.Pages)
db.LoadOptions = dlo;

var pageObject = from op in db.ObjectPermissions
         select op;

// no join needed

Then you can call

pageObject.Pages.PageID

Depending on what your data looks like, you'd probably want to do this the other way around,

DataLoadOptions dlo = new DataLoadOptions();
dlo.LoadWith<Pages>(p => p.ObjectPermissions)
db.LoadOptions = dlo;

var pageObject = from p in db.Pages
                 select p;

// no join needed

var objectPermissionName = pageObject.ObjectPermissions.ObjectPermissionName;

How to list all `env` properties within jenkins pipeline job?

The pure Groovy solutions that read the global env variable don't print all environment variables (e. g. they are missing variables from the environment block, from withEnv context and most of the machine-specific variables from the OS). Using shell steps it is possible to get a more complete set, but that requires a node context, which is not always wanted.

Here is a solution that uses the getContext step to retrieve and print the complete set of environment variables, including pipeline parameters, for the current context.

Caveat: Doesn't work in Groovy sandbox. You can use it from a trusted shared library though.

def envAll = getContext( hudson.EnvVars )
echo envAll.collect{ k, v -> "$k = $v" }.join('\n')

PHP: merge two arrays while keeping keys instead of reindexing?

While this question is quite old I just want to add another possibility of doing a merge while keeping keys.

Besides adding key/values to existing arrays using the + sign you could do an array_replace.

$a = array('foo' => 'bar', 'some' => 'string');
$b = array(42 => 'answer to the life and everything', 1337 => 'leet');

$merged = array_replace($a, $b);

The result will be:

Array
(
  [foo] => bar
  [some] => string
  [42] => answer to the life and everything
  [1337] => leet
)

Same keys will be overwritten by the latter array.
There is also an array_replace_recursive, which do this for subarrays, too.

Live example on 3v4l.org

Bootstrap - 5 column layout

.col-xs-2{
    background:#00f;
    color:#FFF;
}
.col-half-offset{
    margin-left:4.166666667%
}
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet"/>
<div class="container">
    <div class="row" style="border: 1px solid red">
        <div class="col-xs-4" id="p1">One</div>
        <div class="col-xs-4 col-half-offset" id="p2">Two</div>
        <div class="col-xs-4 col-half-offset" id="p3">Three</div>
        <div>Test</div>
    </div>
</div>

get UTC time in PHP

date("Y-m-d H:i:s", time() - date("Z"))

MySQL: Quick breakdown of the types of joins

Full Outer join don't exist in mysql , you might need to use a combination of left and right join.

Remove querystring from URL

If using backbone.js (which contains url anchor as route), url query string may appear:

  1. before url anchor:

    var url = 'http://example.com?a=1&b=3#routepath/subpath';
    
  2. after url anchor:

    var url = 'http://example.com#routepath/subpath?a=1&b=3';
    

Solution:

window.location.href.replace(window.location.search, '');
// run as: 'http://example.com#routepath/subpath?a=1&b=3'.replace('?a=1&b=3', '');

Solving Quadratic Equation

import math   
a = int(input("Enter the coefficients of a: "))
b = int(input("Enter the coefficients of b: "))
c = int(input("Enter the coefficients of c: "))

d = b**2-4*a*c # discriminant

if d < 0:
    print ("This equation has no real solution")
elif d == 0:
    x = (-b+math.sqrt(b**2-4*a*c))/2*a
    print (("This equation has one solutions: "), x)
#add the extra () above or it does not show the answer just the text.
else:
    x1 = (-b+math.sqrt((b**2)-(4*(a*c))))/(2*a)
    x2 = (-b-math.sqrt((b**2)-(4*(a*c))))/(2*a)
    print ("This equation has two solutions: ", x1, " or", x2)

convert month from name to number

Maybe use a combination with strtotime() and date()?

Google OAuth 2 authorization - Error: redirect_uri_mismatch

I needed to create a new client ID under APIs & Services -> Credentials -> Create credentials -> OAuth -> Other

Then I downloaded and used the client_secret.json with my command line program that is uploading to my youtube account. I was trying to use a Web App OAuth client ID which was giving me the redirect URI error in browser.

How to find the location of the Scheduled Tasks folder

I want to extend @Jan answer:

It's seems, that Task Scheduler 1.0 API uses C:\Windows\Tasks folder for create and enumerate tasks (this example), while Task Scheduler 2.0 API uses C:\Windows\System32\Tasks to create and enumerate tasks (this example).

It's also seems, that windows console utility schtasks and GUI utility taskschd.msc uses Task Scheduler 2.0 API.

P.S. I found, that if task placed in C:\Windows\Tasks and have not set AccountInformation, then task won't be displayed in windows console and GUI schedulers. If you set AccountInformation (even "" for SYSTEM account) and set flag TASK_FLAG_RUN_ONLY_IF_LOGGED_ON - task will be displayed in all standard applications.

Solution found here

Where to find htdocs in XAMPP Mac

Open xampp application, then do the following:

  1. go to: volumes,

  2. click the [mount] button, and

  3. finally click explore.

Querying DynamoDB by date

Updated Answer:

DynamoDB allows for specification of secondary indexes to aid in this sort of query. Secondary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist within each hash key partition, thus requiring the hash key to also be specified when making the query.

For the use case in this question, you would want to use a global secondary index on the "CreatedAt" field.

For more on DynamoDB secondary indexes see the secondary index documentation

Original Answer:

DynamoDB does not allow indexed lookups on the range key only. The hash key is required such that the service knows which partition to look in to find the data.

You can of course perform a scan operation to filter by the date value, however this would require a full table scan, so it is not ideal.

If you need to perform an indexed lookup of records by time across multiple primary keys, DynamoDB might not be the ideal service for you to use, or you might need to utilize a separate table (either in DynamoDB or a relational store) to store item metadata that you can perform an indexed lookup against.

Scheduling Python Script to run every hour accurately

   #For scheduling task execution
import schedule
import time

def job():
    print("I'm working...")

schedule.every(1).minutes.do(job)
#schedule.every().hour.do(job)
#schedule.every().day.at("10:30").do(job)
#schedule.every(5).to(10).minutes.do(job)
#schedule.every().monday.do(job)
#schedule.every().wednesday.at("13:15").do(job)
#schedule.every().minute.at(":17").do(job)

while True:
    schedule.run_pending()
    time.sleep(1)

How is using OnClickListener interface different via XML and Java code?

These are exactly the same. android:onClick was added in API level 4 to make it easier, more Javascript-web-like, and drive everything from the XML. What it does internally is add an OnClickListener on the Button, which calls your DoIt method.

Here is what using a android:onClick="DoIt" does internally:

Button button= (Button) findViewById(R.id.buttonId);
button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        DoIt(v);
    }
});

The only thing you trade off by using android:onClick, as usual with XML configuration, is that it becomes a bit more difficult to add dynamic content (programatically, you could decide to add one listener or another depending on your variables). But this is easily defeated by adding your test within the DoIt method.

HTML form with side by side input fields

You could use the {display: inline-flex;} this would produce this: inline-flex

Changing Fonts Size in Matlab Plots

If you want to change font size for all the text in a figure, you can use findall to find all text handles, after which it's easy:

figureHandle = gcf;
%# make all text in the figure to size 14 and bold
set(findall(figureHandle,'type','text'),'fontSize',14,'fontWeight','bold')

C# switch on type

There is a simple answer to this question which uses a dictionary of types to look up a lambda function. Here is how it might be used:

var ts = new TypeSwitch()
    .Case((int x) => Console.WriteLine("int"))
    .Case((bool x) => Console.WriteLine("bool"))
    .Case((string x) => Console.WriteLine("string"));

ts.Switch(42);
ts.Switch(false);
ts.Switch("hello");

There is also a generalized solution to this problem in terms of pattern matching (both types and run-time checked conditions):

var getRentPrice = new PatternMatcher<int>()
    .Case<MotorCycle>(bike => 100 + bike.Cylinders * 10) 
    .Case<Bicycle>(30) 
    .Case<Car>(car => car.EngineType == EngineType.Diesel, car => 220 + car.Doors * 20)
    .Case<Car>(car => car.EngineType == EngineType.Gasoline, car => 200 + car.Doors * 20)
    .Default(0);

var vehicles = new object[] {
    new Car { EngineType = EngineType.Diesel, Doors = 2 },
    new Car { EngineType = EngineType.Diesel, Doors = 4 },
    new Car { EngineType = EngineType.Gasoline, Doors = 3 },
    new Car { EngineType = EngineType.Gasoline, Doors = 5 },
    new Bicycle(),
    new MotorCycle { Cylinders = 2 },
    new MotorCycle { Cylinders = 3 },
};

foreach (var v in vehicles)
{
    Console.WriteLine("Vehicle of type {0} costs {1} to rent", v.GetType(), getRentPrice.Match(v));
}

How to make Python script run as service?

I use this code to daemonize my applications. It allows you start/stop/restart the script using the following commands.

python myscript.py start
python myscript.py stop
python myscript.py restart

In addition to this I also have an init.d script for controlling my service. This allows you to automatically start the service when your operating system boots-up.

Here is a simple example to get your going. Simply move your code inside a class, and call it from the run function inside MyDeamon.

import sys
import time

from daemon import Daemon


class YourCode(object):
    def run(self):
        while True:
            time.sleep(1)


class MyDaemon(Daemon):
    def run(self):
        # Or simply merge your code with MyDaemon.
        your_code = YourCode()
        your_code.run()


if __name__ == "__main__":
    daemon = MyDaemon('/tmp/daemon-example.pid')
    if len(sys.argv) == 2:
        if 'start' == sys.argv[1]:
            daemon.start()
        elif 'stop' == sys.argv[1]:
            daemon.stop()
        elif 'restart' == sys.argv[1]:
            daemon.restart()
        else:
            print "Unknown command"
            sys.exit(2)
        sys.exit(0)
    else:
        print "usage: %s start|stop|restart" % sys.argv[0]
        sys.exit(2)

Upstart

If you are running an operating system that is using Upstart (e.g. CentOS 6) - you can also use Upstart to manage the service. If you use Upstart you can keep your script as is, and simply add something like this under /etc/init/my-service.conf

start on started sshd
stop on runlevel [!2345]

exec /usr/bin/python /opt/my_service.py
respawn

You can then use start/stop/restart to manage your service.

e.g.

start my-service
stop my-service
restart my-service

A more detailed example of working with upstart is available here.

Systemd

If you are running an operating system that uses Systemd (e.g. CentOS 7) you can take a look at the following Stackoverflow answer.

jQuery Popup Bubble/Tooltip

I have programmed an useful jQuery Plugin to create easily smart bubble popups with only a line of code in jQuery!

What You can do: - attach popups to any DOM element! - mouseover/mouseout events automatically managed! - set custom popups events! - create smart shadowed popups! (in IE too!) - choose popup’s style templates at runtime! - insert HTML messages inside popups! - set many options as: distances, velocity, delays, colors…

Popup’s shadows and colorized templates are fully supported by Internet Explorer 6+, Firefox, Opera 9+, Safari

You can download sources from http://plugins.jquery.com/project/jqBubblePopup

Installing PDO driver on MySQL Linux server

Basically the answer from Jani Hartikainen is right! I upvoted his answer. What was missing on my system (based on Ubuntu 15.04) was to enable PDO Extension in my php.ini

extension=pdo.so
extension=pdo_mysql.so

restart the webserver (e.g. with "sudo service apache2 restart") -> every fine :-)

To find where your current active php.ini file is located you can use phpinfo() or some other hints from here: https://www.ostraining.com/blog/coding/phpini-file/

How do you find the current user in a Windows environment?

You can use the username variable: %USERNAME%

How can I install a CPAN module into a local directory?

For Makefile.PL-based distributions, use the INSTALL_BASE option when generating Makefiles:

perl Makefile.PL INSTALL_BASE=/mydir/perl

C++ Boost: undefined reference to boost::system::generic_category()

It's a linker problem. Include the static library path into your project.

For Qt Creator open the project file .pro and add the following line:

LIBS += -L<path for boost libraries in the system> -lboost_system

In my case Ubuntu x86_64:

LIBS += -L/usr/lib/x86_64-linux-gnu -lboost_system

For Codeblocks, open up Settings->Compiler...->Linker settings tab and add:

boost_system

to the Link libraries text widget and press OK button.

Convert JSONObject to Map

The best way to convert it to HashMap<String, Object> is this:

HashMap<String, Object> result = new ObjectMapper().readValue(jsonString, new TypeReference<Map<String, Object>>(){}));

Best practice to return errors in ASP.NET Web API

You can throw a HttpResponseException

HttpResponseMessage response = 
    this.Request.CreateErrorResponse(HttpStatusCode.BadRequest, "your message");
throw new HttpResponseException(response);

Warning: mysql_fetch_array() expects parameter 1 to be resource, boolean given in

The code you have posted doesn't include a call to mysql_fetch_array(). However, what is most likely going wrong is that you are issuing a query that returns an error message, in which case the return value from the query function is false, and attempting to call mysql_fetch_array() on it doesn't work (because boolean false is not a mysql result object).

How to import Angular Material in project?

I am using Angular CLI 9.1.4 and all i did was just run:

ng add @angular/material

And all the angular material packages were installed and my package.json file was updated.

This is the easiest way to get that done.

Best practice to validate null and empty collection in Java

For all the collections including map use: isEmpty method which is there on these collection objects. But you have to do a null check before:

Map<String, String> map;

........
if(map!=null && !map.isEmpty())
......

How can I use/create dynamic template to compile dynamic Component with Angular 2.0?

I myself am trying to see how can I update RC4 to RC5 and thus I stumbled upon this entry and new approach to dynamic component creation still holds a bit of mystery to me, so I wont suggest anything on component factory resolver.

But, what I can suggest is a bit clearer approach to component creation on this scenario - just use switch in template that would create string editor or text editor according to some condition, like this:

<form [ngSwitch]="useTextarea">
    <string-editor *ngSwitchCase="false" propertyName="'code'" 
                 [entity]="entity"></string-editor>
    <text-editor *ngSwitchCase="true" propertyName="'code'" 
                 [entity]="entity"></text-editor>
</form>

And by the way, "[" in [prop] expression have a meaning, this indicates one way data binding, hence you can and even should omit those in case if you know that you do not need to bind property to variable.

UnicodeEncodeError: 'ascii' codec can't encode character at special name

Try setting the system default encoding as utf-8 at the start of the script, so that all strings are encoded using that.

Example -

import sys
reload(sys)
sys.setdefaultencoding('utf-8')

The above should set the default encoding as utf-8 .

How to get every first element in 2 dimensional list

Try using

for i in a :
  print(i[0])

i represents individual row in a.So,i[0] represnts the 1st element of each row.

How to align text below an image in CSS?

I created a jsfiddle for you here: JSFiddle HTML & CSS Example

CSS

div.raspberry {
    float: left;
    margin: 2px;
}

div p {
    text-align: center;
}

HTML (apply CSS above to get what you need)

<div>
    <div class = "raspberry">
        <img src="http://31.media.tumblr.com/tumblr_lwlpl7ZE4z1r8f9ino1_500.jpg" width="100" height="100" alt="Screen 2"/>
        <p>Raspberry <br> For You!</p>
    </div>
    <div class = "raspberry">
        <img src="http://31.media.tumblr.com/tumblr_lwlpl7ZE4z1r8f9ino1_500.jpg" width="100" height="100" alt="Screen 3"/>
        <p>Raspberry <br> For You!</p>
    </div>
    <div class = "raspberry">
        <img src="http://31.media.tumblr.com/tumblr_lwlpl7ZE4z1r8f9ino1_500.jpg" width="100" height="100" alt="Screen 3"/>
        <p>Raspberry <br> For You!</p>
    </div>
</div>

Format datetime in asp.net mvc 4

Thanks Darin, For me, to be able to post to the create method, It only worked after I modified the BindModel code to :

public override object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
    var displayFormat = bindingContext.ModelMetadata.DisplayFormatString;
    var value = bindingContext.ValueProvider.GetValue(bindingContext.ModelName);

    if (!string.IsNullOrEmpty(displayFormat) && value != null)
    {
        DateTime date;
        displayFormat = displayFormat.Replace("{0:", string.Empty).Replace("}", string.Empty);
        // use the format specified in the DisplayFormat attribute to parse the date
         if (DateTime.TryParse(value.AttemptedValue, CultureInfo.GetCultureInfo("en-GB"), DateTimeStyles.None, out date))
        {
            return date;
        }
        else
        {
            bindingContext.ModelState.AddModelError(
                bindingContext.ModelName,
                string.Format("{0} is an invalid date format", value.AttemptedValue)
            );
        }
    }

    return base.BindModel(controllerContext, bindingContext);
}

Hope this could help someone else...

Eliminate extra separators below UITableView

Advancing J. Costa's solution: You can make a global change to the table by putting this line of code:

[[UITableView appearance] setTableFooterView:[[UIView alloc] initWithFrame:CGRectZero]];

inside the first possible method (usually in AppDelegate, in: application:didFinishLaunchingWithOptions: method).

How do I display a MySQL error in PHP for a long query that depends on the user input?

The suggestions don't work because they are for the standard MySQL driver, not for mysqli:

$this->db_link->error contains the error if one did occur

Or

mysqli_error($this->db_link)

will work.

Disable submit button on form submit

A more simplier way. I've tried this and it worked fine for me:

$(':input[type=submit]').prop('disabled', true);

How to make one Observable sequence wait for another to complete before emitting?

Here's a reusable way of doing it (it's typescript but you can adapt it to js):

export function waitFor<T>(signal: Observable<any>) {
    return (source: Observable<T>) =>
        new Observable<T>(observer =>
            signal.pipe(first())
                .subscribe(_ =>
                    source.subscribe(observer)
                )
        );
}

and you can use it like any operator:

var two = someOtherObservable.pipe(waitFor(one), take(1));

It's basically an operator that defers the subscribe on the source observable until the signal observable emits the first event.

Good ways to sort a queryset? - Django

Here's a way that allows for ties for the cut-off score.

author_count = Author.objects.count()
cut_off_score = Author.objects.order_by('-score').values_list('score')[min(30, author_count)]
top_authors = Author.objects.filter(score__gte=cut_off_score).order_by('last_name')

You may get more than 30 authors in top_authors this way and the min(30,author_count) is there incase you have fewer than 30 authors.

Leaflet changing Marker color

Html code for adding map

<div id="map" style="height:480px; width:360px;"></div>

css for loading map

.leaflet-div-icon
{
    background-image: url('http://cloudmade.com/images/layout/cm-logo.png');
}

Logic for changing marker colour


var map = L.map('map').setView([51.5, -0.09], 13);
        
L.marker([51.49, -0.09]).addTo(map)
    .bindPopup('Demo CSS3 popup. <br> Easily customizable.');
        
const myCustomColour = '#5f93ed'
        
const markerHtmlStyles = `
    background-color: ${myCustomColour};
    width: 15px;
    height: 15px;
    font-size:15px;
    text-align:center;
    display: block; 
`
        
function thing(ct) {
    return L.divIcon({
        className: "box",
        iconAnchor: [12, 25],
        labelAnchor: [-6, 0],
        popupAnchor: [0, -15],
        html: `<span style="${markerHtmlStyles}" >M</span>`
    })
}
       
L.marker([51.51, -0.09], {
    icon: thing("hello")
}).addTo(map)
    .bindPopup('divIcon CSS3 popup. <br> Supposed to be easily stylable.');

How do I break out of a loop in Perl?

Oh, I found it. You use last instead of break

for my $entry (@array){
    if ($string eq "text"){
         last;
    }
}

How to get the first element of an array?

Method that works with arrays, and it works with objects too (beware, objects don't have a guaranteed order!).

I prefer this method the most, because original array is not modified.

// In case of array
var arr = [];
arr[3] = 'first';
arr[7] = 'last';
var firstElement;
for(var i in arr){
    firstElement = arr[i];
    break;
}
console.log(firstElement);  // "first"

// In case of object
var obj = {
    first: 'first',
    last: 'last',
};

var firstElement;

for(var i in obj){
    firstElement = obj[i];
    break;
}

console.log(firstElement) // First;

Which HTML elements can receive focus?

Maybe this one can help:

_x000D_
_x000D_
function focus(el){_x000D_
 el.focus();_x000D_
 return el==document.activeElement;_x000D_
}
_x000D_
_x000D_
_x000D_

return value: true = success, false = failed

Reff: https://developer.mozilla.org/en-US/docs/Web/API/DocumentOrShadowRoot/activeElement https://developer.mozilla.org/en-US/docs/Web/API/HTMLElement/focus

How to check db2 version

You can query for the built-in session variables with SQL. To identify the version of DB2 on z/OS, you need the SYSIBM.VERSION variable. This will return the PRDID - the product identifier. You can look up the human-readable version in the Knowledge Center.

SELECT GETVARIABLE('SYSIBM.VERSION')
FROM SYSIBM.SYSDUMMY1;

-- for example, the above returns DSN10015
-- DSN10015 identifies DB2 10 in new-function mode (see second link above)

How do I convert uint to int in C#?

int intNumber = (int)uintNumber;

Depending on what kind of values you are expecting, you may want to check how big uintNumber is before doing the conversion. An int has a max value of about .5 of a uint.

How to detect online/offline event cross-browser?

Since recently, navigator.onLine shows the same on all major browsers, and is thus useable.

if (navigator.onLine) {
  // do things that need connection
} else {
  // do things that don't need connection
}

The oldest versions that support this in the right way are: Firefox 41, IE 9, Chrome 14 and Safari 5.

Currently this will represent almost the whole spectrum of users, but you should always check what the users of your page have of capabilities.

Previous to FF 41, it would only show false if the user put the browser manually in offline mode. In IE 8, the property was on the body, instead of window.

source: caniuse

Installing Homebrew on OS X

I faced the same problem of brew command not found while installing Homebrew on mac BigSur with M1 processor.

I - Install XCode if it is not installed yet.

II - Select terminal.app in Finder.

III - RMB click on Terminal and select "Get Info"

IV - Select Open using Rosetta checkbox.

V - Close any open Terminal windows.

VI - Open a new Terminal window and install Hobebrew:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"

VII - Test Homebrew installation.

IIX - Uncheck Open using Rosetta checkbox.

How do I update the password for Git?

In my Windows machine, I tried the solution of @nzrytmn i.e., Control Panel>Search Credentials>Select "ManageCredentials">modified new credentials under git option category corresponding to my username. And then,

Deleted current password:

git config --global --unset user.password

Added new password:

git config --global --add user.password "new_password"

And It worked for me.

How to count the number of occurrences of an element in a List

So do it the old fashioned way and roll your own:

Map<String, Integer> instances = new HashMap<String, Integer>();

void add(String name) {
     Integer value = instances.get(name);
     if (value == null) {
        value = new Integer(0);
        instances.put(name, value);
     }
     instances.put(name, value++);
}

What is the difference between `sorted(list)` vs `list.sort()`?

What is the difference between sorted(list) vs list.sort()?

  • list.sort mutates the list in-place & returns None
  • sorted takes any iterable & returns a new list, sorted.

sorted is equivalent to this Python implementation, but the CPython builtin function should run measurably faster as it is written in C:

def sorted(iterable, key=None):
    new_list = list(iterable)    # make a new list
    new_list.sort(key=key)       # sort it
    return new_list              # return it

when to use which?

  • Use list.sort when you do not wish to retain the original sort order (Thus you will be able to reuse the list in-place in memory.) and when you are the sole owner of the list (if the list is shared by other code and you mutate it, you could introduce bugs where that list is used.)
  • Use sorted when you want to retain the original sort order or when you wish to create a new list that only your local code owns.

Can a list's original positions be retrieved after list.sort()?

No - unless you made a copy yourself, that information is lost because the sort is done in-place.

"And which is faster? And how much faster?"

To illustrate the penalty of creating a new list, use the timeit module, here's our setup:

import timeit
setup = """
import random
lists = [list(range(10000)) for _ in range(1000)]  # list of lists
for l in lists:
    random.shuffle(l) # shuffle each list
shuffled_iter = iter(lists) # wrap as iterator so next() yields one at a time
"""

And here's our results for a list of randomly arranged 10000 integers, as we can see here, we've disproven an older list creation expense myth:

Python 2.7

>>> timeit.repeat("next(shuffled_iter).sort()", setup=setup, number = 1000)
[3.75168503401801, 3.7473005310166627, 3.753129180986434]
>>> timeit.repeat("sorted(next(shuffled_iter))", setup=setup, number = 1000)
[3.702025591977872, 3.709248117986135, 3.71071034099441]

Python 3

>>> timeit.repeat("next(shuffled_iter).sort()", setup=setup, number = 1000)
[2.797430992126465, 2.796825885772705, 2.7744789123535156]
>>> timeit.repeat("sorted(next(shuffled_iter))", setup=setup, number = 1000)
[2.675589084625244, 2.8019039630889893, 2.849375009536743]

After some feedback, I decided another test would be desirable with different characteristics. Here I provide the same randomly ordered list of 100,000 in length for each iteration 1,000 times.

import timeit
setup = """
import random
random.seed(0)
lst = list(range(100000))
random.shuffle(lst)
"""

I interpret this larger sort's difference coming from the copying mentioned by Martijn, but it does not dominate to the point stated in the older more popular answer here, here the increase in time is only about 10%

>>> timeit.repeat("lst[:].sort()", setup=setup, number = 10000)
[572.919036605, 573.1384446719999, 568.5923951]
>>> timeit.repeat("sorted(lst[:])", setup=setup, number = 10000)
[647.0584738299999, 653.4040515829997, 657.9457361929999]

I also ran the above on a much smaller sort, and saw that the new sorted copy version still takes about 2% longer running time on a sort of 1000 length.

Poke ran his own code as well, here's the code:

setup = '''
import random
random.seed(12122353453462456)
lst = list(range({length}))
random.shuffle(lst)
lists = [lst[:] for _ in range({repeats})]
it = iter(lists)
'''
t1 = 'l = next(it); l.sort()'
t2 = 'l = next(it); sorted(l)'
length = 10 ** 7
repeats = 10 ** 2
print(length, repeats)
for t in t1, t2:
    print(t)
    print(timeit(t, setup=setup.format(length=length, repeats=repeats), number=repeats))

He found for 1000000 length sort, (ran 100 times) a similar result, but only about a 5% increase in time, here's the output:

10000000 100
l = next(it); l.sort()
610.5015971539542
l = next(it); sorted(l)
646.7786222379655

Conclusion:

A large sized list being sorted with sorted making a copy will likely dominate differences, but the sorting itself dominates the operation, and organizing your code around these differences would be premature optimization. I would use sorted when I need a new sorted list of the data, and I would use list.sort when I need to sort a list in-place, and let that determine my usage.

How to extract text from a string using sed?

How about using grep -E?

echo "This is 02G05 a test string 20-Jul-2012" | grep -Eo '[0-9]+G[0-9]+'

MySQL SELECT x FROM a WHERE NOT IN ( SELECT x FROM b ) - Unexpected result

I'm a little out of touch with the details of how MySQL deals with nulls, but here's two things to try:

SELECT * FROM match WHERE id NOT IN 
    ( SELECT id FROM email WHERE id IS NOT NULL) ;

SELECT
    m.*
FROM
    match m
    LEFT OUTER JOIN email e ON
        m.id = e.id
        AND e.id IS NOT NULL
WHERE
    e.id IS NULL

The second query looks counter intuitive, but it does the join condition and then the where condition. This is the case where joins and where clauses are not equivalent.

How can you detect the version of a browser?

Detecting Browser and Its version

This code snippet is based on the article from MDN. Where they gave a brief hint about various keywords that can be used to detect the browser name.

reference

I have done few changes to detect browsers like Edge and UCBrowser

_x000D_
_x000D_
getBrowser = () => {
    const userAgent = navigator.userAgent;
    let browser = "unkown";
    // Detect browser name
    browser = (/ucbrowser/i).test(userAgent) ? 'UCBrowser' : browser;
    browser = (/edg/i).test(userAgent) ? 'Edge' : browser;
    browser = (/googlebot/i).test(userAgent) ? 'GoogleBot' : browser;
    browser = (/chromium/i).test(userAgent) ? 'Chromium' : browser;
    browser = (/firefox|fxios/i).test(userAgent) && !(/seamonkey/i).test(userAgent) ? 'Firefox' : browser;
    browser = (/; msie|trident/i).test(userAgent) && !(/ucbrowser/i).test(userAgent) ? 'IE' : browser;
    browser = (/chrome|crios/i).test(userAgent) && !(/opr|opera|chromium|edg|ucbrowser|googlebot/i).test(userAgent) ? 'Chrome' : browser;;
    browser = (/safari/i).test(userAgent) && !(/chromium|edg|ucbrowser|chrome|crios|opr|opera|fxios|firefox/i).test(userAgent) ? 'Safari' : browser;
    browser = (/opr|opera/i).test(userAgent) ? 'Opera' : browser;

    // detect browser version
    switch (browser) {
        case 'UCBrowser': return `${browser}/${browserVersion(userAgent,/(ucbrowser)\/([\d\.]+)/i)}`;
        case 'Edge': return `${browser}/${browserVersion(userAgent,/(edge|edga|edgios|edg)\/([\d\.]+)/i)}`;
        case 'GoogleBot': return `${browser}/${browserVersion(userAgent,/(googlebot)\/([\d\.]+)/i)}`;
        case 'Chromium': return `${browser}/${browserVersion(userAgent,/(chromium)\/([\d\.]+)/i)}`;
        case 'Firefox': return `${browser}/${browserVersion(userAgent,/(firefox|fxios)\/([\d\.]+)/i)}`;
        case 'Chrome': return `${browser}/${browserVersion(userAgent,/(chrome|crios)\/([\d\.]+)/i)}`;
        case 'Safari': return `${browser}/${browserVersion(userAgent,/(safari)\/([\d\.]+)/i)}`;
        case 'Opera': return `${browser}/${browserVersion(userAgent,/(opera|opr)\/([\d\.]+)/i)}`;
        case 'IE': const version = browserVersion(userAgent,/(trident)\/([\d\.]+)/i);
            // IE version is mapped using trident version 
            // IE/8.0 = Trident/4.0, IE/9.0 = Trident/5.0
            return version ? `${browser}/${parseFloat(version) + 4.0}` : `${browser}/7.0`;
        default: return `unknown/0.0.0.0`;
    }
}

browserVersion = (userAgent,regex) => {
    return userAgent.match(regex) ? userAgent.match(regex)[2] : null;
}

console.log(getBrowser());
_x000D_
_x000D_
_x000D_

How can I make SMTP authenticated in C#

To send a message through TLS/SSL, you need to set Ssl of the SmtpClient class to true.

string to = "[email protected]";
string from = "[email protected]";
MailMessage message = new MailMessage(from, to);
message.Subject = "Using the new SMTP client.";
message.Body = @"Using this new feature, you can send an e-mail message from an application very easily.";
SmtpClient client = new SmtpClient(server);
// Credentials are necessary if the server requires the client 
// to authenticate before it will send e-mail on the client's behalf.
client.UseDefaultCredentials = true;
client.EnableSsl = true;
client.Send(message);

Composer killed while updating

Solved on Laravel/Homestead (Vagrant Windows)

  1. Edit Homestead.yaml and increase memory from 2048 to 4096

  2. vagrant up

  3. vagrant ssh

  4. Install Symfony with this line on the folder you choose (must be without files)

    COMPOSER_MEMORY_LIMIT=-1 composer create-project symfony/website-skeleton . -s dev
    

Working copy XXX locked and cleanup failed in SVN

The easiest way to do this is show hidden folders and then open the .SVN folder. You should see a zero KB file named "lock" deleting this will fix the problem

Big-O summary for Java Collections Framework implementations?

The book Java Generics and Collections has this information (pages: 188, 211, 222, 240).

List implementations:

                      get  add  contains next remove(0) iterator.remove
ArrayList             O(1) O(1) O(n)     O(1) O(n)      O(n)
LinkedList            O(n) O(1) O(n)     O(1) O(1)      O(1)
CopyOnWrite-ArrayList O(1) O(n) O(n)     O(1) O(n)      O(n)

Set implementations:

                      add      contains next     notes
HashSet               O(1)     O(1)     O(h/n)   h is the table capacity
LinkedHashSet         O(1)     O(1)     O(1) 
CopyOnWriteArraySet   O(n)     O(n)     O(1) 
EnumSet               O(1)     O(1)     O(1) 
TreeSet               O(log n) O(log n) O(log n)
ConcurrentSkipListSet O(log n) O(log n) O(1)

Map implementations:

                      get      containsKey next     Notes
HashMap               O(1)     O(1)        O(h/n)   h is the table capacity
LinkedHashMap         O(1)     O(1)        O(1) 
IdentityHashMap       O(1)     O(1)        O(h/n)   h is the table capacity 
EnumMap               O(1)     O(1)        O(1) 
TreeMap               O(log n) O(log n)    O(log n) 
ConcurrentHashMap     O(1)     O(1)        O(h/n)   h is the table capacity 
ConcurrentSkipListMap O(log n) O(log n)    O(1)

Queue implementations:

                      offer    peek poll     size
PriorityQueue         O(log n) O(1) O(log n) O(1)
ConcurrentLinkedQueue O(1)     O(1) O(1)     O(n)
ArrayBlockingQueue    O(1)     O(1) O(1)     O(1)
LinkedBlockingQueue   O(1)     O(1) O(1)     O(1)
PriorityBlockingQueue O(log n) O(1) O(log n) O(1)
DelayQueue            O(log n) O(1) O(log n) O(1)
LinkedList            O(1)     O(1) O(1)     O(1)
ArrayDeque            O(1)     O(1) O(1)     O(1)
LinkedBlockingDeque   O(1)     O(1) O(1)     O(1)

The bottom of the javadoc for the java.util package contains some good links:

No signing certificate "iOS Distribution" found

enter image description here

Solution Steps:

  1. Unchecked "Automatically manage signing".

  2. Select "Provisioning profile" in "Signing (Release)" section.

  3. No signing certificate error will be show.

  4. Then below the error has a "Manage Certificates" button. click the button.

enter image description here

  1. This window will come. Click the + sign and click "iOS Distribution". xcode will create the private key for your distribution certificate and error will be gone.

Postgres user does not exist?

OS X tends to prefix the system account names with "_"; you don't say what version of OS X you're using, but at least in 10.8 and 10.9 the _postgres user exists in a default install. Note that you won't be able to su to this account (except as root), since it doesn't have a password. sudo -u _postgres, on the other hand, should work fine.

Exporting functions from a DLL with dllexport

If you want plain C exports, use a C project not C++. C++ DLLs rely on name-mangling for all the C++isms (namespaces etc...). You can compile your code as C by going into your project settings under C/C++->Advanced, there is an option "Compile As" which corresponds to the compiler switches /TP and /TC.

If you still want to use C++ to write the internals of your lib but export some functions unmangled for use outside C++, see the second section below.

Exporting/Importing DLL Libs in VC++

What you really want to do is define a conditional macro in a header that will be included in all of the source files in your DLL project:

#ifdef LIBRARY_EXPORTS
#    define LIBRARY_API __declspec(dllexport)
#else
#    define LIBRARY_API __declspec(dllimport)
#endif

Then on a function that you want to be exported you use LIBRARY_API:

LIBRARY_API int GetCoolInteger();

In your library build project create a define LIBRARY_EXPORTS this will cause your functions to be exported for your DLL build.

Since LIBRARY_EXPORTS will not be defined in a project consuming the DLL, when that project includes the header file of your library all of the functions will be imported instead.

If your library is to be cross-platform you can define LIBRARY_API as nothing when not on Windows:

#ifdef _WIN32
#    ifdef LIBRARY_EXPORTS
#        define LIBRARY_API __declspec(dllexport)
#    else
#        define LIBRARY_API __declspec(dllimport)
#    endif
#elif
#    define LIBRARY_API
#endif

When using dllexport/dllimport you do not need to use DEF files, if you use DEF files you do not need to use dllexport/dllimport. The two methods accomplish the same task different ways, I believe that dllexport/dllimport is the recommended method out of the two.

Exporting unmangled functions from a C++ DLL for LoadLibrary/PInvoke

If you need this to use LoadLibrary and GetProcAddress, or maybe importing from another language (i.e PInvoke from .NET, or FFI in Python/R etc) you can use extern "C" inline with your dllexport to tell the C++ compiler not to mangle the names. And since we are using GetProcAddress instead of dllimport we don't need to do the ifdef dance from above, just a simple dllexport:

The Code:

#define EXTERN_DLL_EXPORT extern "C" __declspec(dllexport)

EXTERN_DLL_EXPORT int getEngineVersion() {
  return 1;
}

EXTERN_DLL_EXPORT void registerPlugin(Kernel &K) {
  K.getGraphicsServer().addGraphicsDriver(
    auto_ptr<GraphicsServer::GraphicsDriver>(new OpenGLGraphicsDriver())
  );
}

And here's what the exports look like with Dumpbin /exports:

  Dump of file opengl_plugin.dll

  File Type: DLL

  Section contains the following exports for opengl_plugin.dll

    00000000 characteristics
    49866068 time date stamp Sun Feb 01 19:54:32 2009
        0.00 version
           1 ordinal base
           2 number of functions
           2 number of names

    ordinal hint RVA      name

          1    0 0001110E getEngineVersion = @ILT+265(_getEngineVersion)
          2    1 00011028 registerPlugin = @ILT+35(_registerPlugin)

So this code works fine:

m_hDLL = ::LoadLibrary(T"opengl_plugin.dll");

m_pfnGetEngineVersion = reinterpret_cast<fnGetEngineVersion *>(
  ::GetProcAddress(m_hDLL, "getEngineVersion")
);
m_pfnRegisterPlugin = reinterpret_cast<fnRegisterPlugin *>(
  ::GetProcAddress(m_hDLL, "registerPlugin")
);

How do you load custom UITableViewCells from Xib files?

Register

After iOS 7, this process has been simplified down to (swift 3.0):

// For registering nib files
tableView.register(UINib(nibName: "MyCell", bundle: Bundle.main), forCellReuseIdentifier: "cell")

// For registering classes
tableView.register(MyCellClass.self, forCellReuseIdentifier: "cell")

(Note) This is also achievable by creating the cells in the .xib or .stroyboard files, as prototype cells. If you need to attach a class to them, you can select the cell prototype and add the corresponding class (must be a descendant of UITableViewCell, of course).

Dequeue

And later on, dequeued using (swift 3.0):

override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
    let cell : UITableViewCell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)

    cell.textLabel?.text = "Hello"

    return cell
}

The difference being that this new method not only dequeues the cell, it also creates if non-existant (that means that you don't have to do if (cell == nil) shenanigans), and the cell is ready to use just as in the example above.

(Warning) tableView.dequeueReusableCell(withIdentifier:for:) has the new behavior, if you call the other one (without indexPath:) you get the old behavior, in which you need to check for nil and instance it yourself, notice the UITableViewCell? return value.

if let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath) as? MyCellClass
{
    // Cell be casted properly
    cell.myCustomProperty = true
}
else
{
    // Wrong type? Wrong identifier?
}

And of course, the type of the associated class of the cell is the one you defined in the .xib file for the UITableViewCell subclass, or alternatively, using the other register method.

Configuration

Ideally, your cells have been already configured in terms of appearance and content positioning (like labels and image views) by the time you registered them, and on the cellForRowAtIndexPath method you simply fill them in.

All together

class MyCell : UITableViewCell
{
    // Can be either created manually, or loaded from a nib with prototypes
    @IBOutlet weak var labelSomething : UILabel? = nil
}

class MasterViewController: UITableViewController 
{
    var data = ["Hello", "World", "Kinda", "Cliche", "Though"]

    // Register
    override func viewDidLoad()
    {
        super.viewDidLoad()

        tableView.register(MyCell.self, forCellReuseIdentifier: "mycell")
        // or the nib alternative
    }

    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int
    {
        return data.count
    }

    // Dequeue
    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
    {
        let cell = tableView.dequeueReusableCell(withIdentifier: "mycell", for: indexPath) as! MyCell

        cell.labelSomething?.text = data[indexPath.row]

        return cell
    }
}

And of course, this is all available in ObjC with the same names.

How do I get the path of the assembly the code is in?

You can get the bin path by AppDomain.CurrentDomain.RelativeSearchPath

How to sleep for five seconds in a batch file/cmd

It can be done with two simple lines in a batch file: write a temporary .vbs file in the %temp% folder and call it:

echo WScript.Sleep(5000) >"%temp%\sleep.vbs"
cscript "%temp%\sleep.vbs"

Why not use Double or Float to represent currency?

This is not a matter of accuracy, nor is it a matter of precision. It is a matter of meeting the expectations of humans who use base 10 for calculations instead of base 2. For example, using doubles for financial calculations does not produce answers that are "wrong" in a mathematical sense, but it can produce answers that are not what is expected in a financial sense.

Even if you round off your results at the last minute before output, you can still occasionally get a result using doubles that does not match expectations.

Using a calculator, or calculating results by hand, 1.40 * 165 = 231 exactly. However, internally using doubles, on my compiler / operating system environment, it is stored as a binary number close to 230.99999... so if you truncate the number, you get 230 instead of 231. You may reason that rounding instead of truncating would have given the desired result of 231. That is true, but rounding always involves truncation. Whatever rounding technique you use, there are still boundary conditions like this one that will round down when you expect it to round up. They are rare enough that they often will not be found through casual testing or observation. You may have to write some code to search for examples that illustrate outcomes that do not behave as expected.

Assume you want to round something to the nearest penny. So you take your final result, multiply by 100, add 0.5, truncate, then divide the result by 100 to get back to pennies. If the internal number you stored was 3.46499999.... instead of 3.465, you are going to get 3.46 instead 3.47 when you round the number to the nearest penny. But your base 10 calculations may have indicated that the answer should be 3.465 exactly, which clearly should round up to 3.47, not down to 3.46. These kinds of things happen occasionally in real life when you use doubles for financial calculations. It is rare, so it often goes unnoticed as an issue, but it happens.

If you use base 10 for your internal calculations instead of doubles, the answers are always exactly what is expected by humans, assuming no other bugs in your code.

Best way to remove from NSMutableArray while iterating?

Some of the other answers would have poor performance on very large arrays, because methods like removeObject: and removeObjectsInArray: involve doing a linear search of the receiver, which is a waste because you already know where the object is. Also, any call to removeObjectAtIndex: will have to copy values from the index to the end of the array up by one slot at a time.

More efficient would be the following:

NSMutableArray *array = ...
NSMutableArray *itemsToKeep = [NSMutableArray arrayWithCapacity:[array count]];
for (id object in array) {
    if (! shouldRemove(object)) {
        [itemsToKeep addObject:object];
    }
}
[array setArray:itemsToKeep];

Because we set the capacity of itemsToKeep, we don't waste any time copying values during a resize. We don't modify the array in place, so we are free to use Fast Enumeration. Using setArray: to replace the contents of array with itemsToKeep will be efficient. Depending on your code, you could even replace the last line with:

[array release];
array = [itemsToKeep retain];

So there isn't even a need to copy values, only swap a pointer.

How to convert string to boolean in typescript Angular 4

Method 1 :

var stringValue = "true";
var boolValue = (/true/i).test(stringValue) //returns true

Method 2 :

var stringValue = "true";
var boolValue = (stringValue =="true");   //returns true

Method 3 :

var stringValue = "true";
var boolValue = JSON.parse(stringValue);   //returns true

Method 4 :

var stringValue = "true";
var boolValue = stringValue.toLowerCase() == 'true'; //returns true

Method 5 :

var stringValue = "true";
var boolValue = getBoolean(stringValue); //returns true
function getBoolean(value){
   switch(value){
        case true:
        case "true":
        case 1:
        case "1":
        case "on":
        case "yes":
            return true;
        default: 
            return false;
    }
}

source: http://codippa.com/how-to-convert-string-to-boolean-javascript/

How to get a variable value if variable name is stored as string?

Had the same issue with arrays, here is how to do it if you're manipulating arrays too :

array_name="ARRAY_NAME"
ARRAY_NAME=("Val0" "Val1" "Val2")

ARRAY=$array_name[@]
echo "ARRAY=${ARRAY}"
ARRAY=("${!ARRAY}")
echo "ARRAY=${ARRAY[@]}"
echo "ARRAY[0]=${ARRAY[0]}"
echo "ARRAY[1]=${ARRAY[1]}"
echo "ARRAY[2]=${ARRAY[2]}"

This will output :

ARRAY=ARRAY_NAME[@]
ARRAY=Val0 Val1 Val2
ARRAY[0]=Val0
ARRAY[1]=Val1
ARRAY[2]=Val2

SQL multiple column ordering

The other answers lack a concrete example, so here it goes:

Given the following People table:

 FirstName |  LastName   |  YearOfBirth
----------------------------------------
  Thomas   | Alva Edison |   1847
  Benjamin | Franklin    |   1706
  Thomas   | More        |   1478
  Thomas   | Jefferson   |   1826

If you execute the query below:

SELECT * FROM People ORDER BY FirstName DESC, YearOfBirth ASC

The result set will look like this:

 FirstName |  LastName   |  YearOfBirth
----------------------------------------
  Thomas   | More        |   1478
  Thomas   | Jefferson   |   1826
  Thomas   | Alva Edison |   1847
  Benjamin | Franklin    |   1706

How to plot multiple functions on the same figure, in Matplotlib?

To plot multiple graphs on the same figure you will have to do:

from numpy import *
import math
import matplotlib.pyplot as plt

t = linspace(0, 2*math.pi, 400)
a = sin(t)
b = cos(t)
c = a + b

plt.plot(t, a, 'r') # plotting t, a separately 
plt.plot(t, b, 'b') # plotting t, b separately 
plt.plot(t, c, 'g') # plotting t, c separately 
plt.show()

enter image description here

How to install sklearn?

I would recommend you look at getting the anaconda package, it will install and configure Sklearn and its dependencies.

https://www.continuum.io

Move textfield when keyboard appears swift

If you are like me who has tried all the above solutions and still your problem is not solved, I have a got a great solution for you that works like a charm. First I want clarify few things about some of solutions mentioned above.

  1. In my case IQkeyboardmanager was working only when there is no auto layout applied on the elements, if it is applied then IQkeyboard manager will not work the way we think.
  2. Same thing with upward movement of self.view.
  3. i have wriiten a objective c header with a swift support for pushing UITexfield upward when user clicks on it, solving the problem of keyboard covering the UITextfield : https://github.com/coolvasanth/smart_keyboard.
  4. One who has An intermediate or higher level in iOS app development can easily understand the repository and implement it. All the best

push multiple elements to array

There are many answers recommend to use: Array.prototype.push(a, b). It's nice way, BUT if you will have really big b, you will have stack overflow error (because of too many args). Be careful here.

See What is the most efficient way to concatenate N arrays? for more details.

Sort a list of tuples by 2nd item (integer value)

>>> from operator import itemgetter
>>> data = [('abc', 121),('abc', 231),('abc', 148), ('abc',221)]
>>> sorted(data,key=itemgetter(1))
[('abc', 121), ('abc', 148), ('abc', 221), ('abc', 231)]

IMO using itemgetter is more readable in this case than the solution by @cheeken. It is also faster since almost all of the computation will be done on the c side (no pun intended) rather than through the use of lambda.

>python -m timeit -s "from operator import itemgetter; data = [('abc', 121),('abc', 231),('abc', 148), ('abc',221)]" "sorted(data,key=itemgetter(1))"
1000000 loops, best of 3: 1.22 usec per loop

>python -m timeit -s "data = [('abc', 121),('abc', 231),('abc', 148), ('abc',221)]" "sorted(data,key=lambda x: x[1])"
1000000 loops, best of 3: 1.4 usec per loop

Entity Framework and Connection Pooling

Below code helped my object to be refreshed with fresh database values. The Entry(object).Reload() command forces the object to recall database values

GM_MEMBERS member = DatabaseObjectContext.GM_MEMBERS.FirstOrDefault(p => p.Username == username && p.ApplicationName == this.ApplicationName);
DatabaseObjectContext.Entry(member).Reload();

How do I merge a git tag onto a branch

Remember before you merge you need to update the tag, it's quite different from branches (git pull origin tag_name won't update your local tags). Thus, you need the following command:

git fetch --tags origin

Then you can perform git merge tag_name to merge the tag onto a branch.

Validating IPv4 addresses with regexp

Following is the regex expression to validate the IP-Address.

^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$

How to calculate cumulative normal distribution?

Taken from above:

from scipy.stats import norm
>>> norm.cdf(1.96)
0.9750021048517795
>>> norm.cdf(-1.96)
0.024997895148220435

For a two-tailed test:

Import numpy as np
z = 1.96
p_value = 2 * norm.cdf(-np.abs(z))
0.04999579029644087

submitting a form when a checkbox is checked

Yes, this is possible.

<form id="formName" action="<?php echo $_SERVER['PHP_SELF'];?>" method="get">
    <input type ="checkbox" name="cBox[]" value = "3" onchange="document.getElementById('formName').submit()">3</input>
    <input type ="checkbox" name="cBox[]" value = "4" onchange="document.getElementById('formName').submit()">4</input>
    <input type ="checkbox" name="cBox[]" value = "5" onchange="document.getElementById('formName').submit()">5</input>
    <input type="submit" name="submit" value="Search" />
</form>

By adding onchange="document.getElementById('formName').submit()" to each checkbox, you'll submit any time a checkbox is changed.

If you're OK with jQuery, it's even easier (and unobtrusive):

$(document).ready(function(){
    $("#formname").on("change", "input:checkbox", function(){
        $("#formname").submit();
    });
});

For any number of checkboxes in your form, when the "change" event happens, the form is submitted. This will even work if you dynamically create more checkboxes thanks to the .on() method.

How to use if - else structure in a batch file?

Here's my code Example for if..else..if
which do the following

Prompt user for Process Name

If the process name is invalid
Then it's write to user

Error : The Processor above doesn't seem to be exist 

if the process name is services
Then it's write to user

Error : You can't kill the Processor above 

if the process name is valid and not services
Then it's write to user

the process has been killed via taskill

so i called it Process killer.bat
Here's my Code:

@echo off

:Start
Rem preparing the batch  
cls
Title Processor Killer
Color 0B
Echo Type Processor name to kill It (Without ".exe")
set /p ProcessorTokill=%=%  

:tasklist
tasklist|find /i "%ProcessorTokill%.exe">nul & if errorlevel 1 (
REM check if the process name is invalid 
Cls 
Title %ProcessorTokill% Not Found
Color 0A
echo %ProcessorTokill%
echo Error : The Processor above doesn't seem to be exist    

) else if %ProcessorTokill%==services (
REM check if the process name is services and doesn't kill it
Cls 
Color 0c
Title Permission denied 
echo "%ProcessorTokill%.exe"
echo Error : You can't kill the Processor above 

) else (
REM if the process name is valid and not services
Cls 
Title %ProcessorTokill% Found
Color 0e
echo %ProcessorTokill% Found
ping localhost -n 2 -w 1000>nul
echo Killing %ProcessorTokill% ...
taskkill /f /im %ProcessorTokill%.exe /t>nul
echo %ProcessorTokill% Killed...
)

pause>nul



REM If else if Template
REM if thing1 (
REM Command here 2 ! 
REM ) else if thing2 (
REM command here 2 !
REM ) else (
REM command here 3 !
REM )

Async image loading from url inside a UITableView cell - image changes to wrong image while scrolling

/* I have done it this way, and also tested it */

Step 1 = Register custom cell class (in case of prototype cell in table) or nib (in case of custom nib for custom cell) for table like this in viewDidLoad method:

[self.yourTableView registerClass:[CustomTableViewCell class] forCellReuseIdentifier:@"CustomCell"];

OR

[self.yourTableView registerNib:[UINib nibWithNibName:@"CustomTableViewCell" bundle:nil] forCellReuseIdentifier:@"CustomCell"];

Step 2 = Use UITableView's "dequeueReusableCellWithIdentifier: forIndexPath:" method like this (for this, you must register class or nib) :

   - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
            CustomTableViewCell * cell = [tableView dequeueReusableCellWithIdentifier:@"CustomCell" forIndexPath:indexPath];

            cell.imageViewCustom.image = nil; // [UIImage imageNamed:@"default.png"];
            cell.textLabelCustom.text = @"Hello";

            dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
                // retrive image on global queue
                UIImage * img = [UIImage imageWithData:[NSData dataWithContentsOfURL:     [NSURL URLWithString:kImgLink]]];

                dispatch_async(dispatch_get_main_queue(), ^{

                    CustomTableViewCell * cell = (CustomTableViewCell *)[tableView cellForRowAtIndexPath:indexPath];
                  // assign cell image on main thread
                    cell.imageViewCustom.image = img;
                });
            });

            return cell;
        }

How to choose an AWS profile when using boto3 to connect to CloudFront

This section of the boto3 documentation is helpful.

Here's what worked for me:

session = boto3.Session(profile_name='dev')
client = session.client('cloudfront')

Xcode 12, building for iOS Simulator, but linking in object file built for iOS, for architecture arm64

Switch Build Configuration back to Debug mode or turn on Build Active Architecture Only for both Debug and Release mode. The reason is your library/framework doesn't support new Simulator architecture ARM64 (run on Mac with Apple Silicon processor)

Reading an Excel file in PHP

I'm using below excel file url: https://github.com/inventorbala/Sample-Excel-files/blob/master/sample-excel-files.xlsx

Output:

Array
    (
        [0] => Array
            (
                [store_id] => 3716
                [employee_uid] => 664368
                [opus_id] => zh901j
                [item_description] => PRE ATT $75 PNLS 90EXP
                [opus_transaction_date] => 2019-10-18
                [opus_transaction_num] => X2MBV1DJKSLQW
                [opus_invoice_num] => O3716IN3409
                [customer_name] => BILL PHILLIPS
                [mobile_num] => 4052380136
                [opus_amount] => 75
                [rq4_amount] => 0
                [difference] => -75
                [ocomment] => Re-Upload: We need RQ4 transaction for October.  If you're unable to provide the October invoice, it will be counted as EPin shortage.
                [mark_delete] => 0
                [upload_date] => 2019-10-20
            )

        [1] => Array
            (
                [store_id] => 2710
                [employee_uid] => 75899
                [opus_id] => dc288t
                [item_description] => PRE ATT $50 PNLS 90EXP
                [opus_transaction_date] => 2019-10-18
                [opus_transaction_num] => XJ90419JKT9R9
                [opus_invoice_num] => M2710IN868
                [customer_name] => CALEB MENDEZ
                [mobile_num] => 6517672079
                [opus_amount] => 50
                [rq4_amount] => 0
                [difference] => -50
                [ocomment] => No Response.  Re-Upload
                [mark_delete] => 0
                [upload_date] => 2019-10-20
            )

        [2] => Array
            (
                [store_id] => 0136
                [employee_uid] => 70167
                [opus_id] => fv766x
                [item_description] => PRE ATT $50 PNLS 90EXP
                [opus_transaction_date] => 2019-10-18
                [opus_transaction_num] => XQ57316JKST1V
                [opus_invoice_num] => GONZABP25622
                [customer_name] => FAUSTINA CASTILLO
                [mobile_num] => 8302638628
                [opus_amount] => 100
                [rq4_amount] => 50
                [difference] => -50
                [ocomment] => Re-Upload: We have been charged in opus for $100. Provide RQ4 invoice number for remaining amount
                [mark_delete] => 0
                [upload_date] => 2019-10-20
            )

        [3] => Array
            (
                [store_id] => 3264
                [employee_uid] => 23723
                [opus_id] => aa297h
                [item_description] => PRE ATT $25 PNLS 90EXP
                [opus_transaction_date] => 2019-10-19
                [opus_transaction_num] => XR1181HJKW9MP
                [opus_invoice_num] => C3264IN1588
                [customer_name] => SOPHAT VANN
                [mobile_num] => 9494668372
                [opus_amount] => 70
                [rq4_amount] => 25
                [difference] => -45
                [ocomment] => No Response.  Re-Upload
                [mark_delete] => 0
                [upload_date] => 2019-10-20
            )

        [4] => Array
            (
                [store_id] => 4166
                [employee_uid] => 568494
                [opus_id] => ab7598
                [item_description] => PRE ATT $40 RTR
                [opus_transaction_date] => 2019-10-20
                [opus_transaction_num] => X8F58P3JL2RFU
                [opus_invoice_num] => I4166IN2481
                [customer_name] => KELLY MC GUIRE
                [mobile_num] => 6189468180
                [opus_amount] => 40
                [rq4_amount] => 0
                [difference] => -40
                [ocomment] => Re-Upload: The invoice number that you provided (I4166IN2481) belongs to September transaction.  We need RQ4 transaction for October.  If you're unable to provide the October invoice, it will be counted as EPin shortage.
                [mark_delete] => 0
                [upload_date] => 2019-10-21
            )

        [5] => Array
            (
                [store_id] => 4508
                [employee_uid] => 552502
                [opus_id] => ec850x
                [item_description] => $30 RTR
                [opus_transaction_date] => 2019-10-20
                [opus_transaction_num] => XPL7M1BJL1W5D
                [opus_invoice_num] => M4508IN6024
                [customer_name] => PREPAID CUSTOMER
                [mobile_num] => 6019109730
                [opus_amount] => 30
                [rq4_amount] => 0
                [difference] => -30
                [ocomment] => Re-Upload: The invoice number you provided (M4508IN7217) belongs to a different phone number.  We need RQ4 transaction for the phone number in question.  If you're unable to provide the RQ4 invoice for this transaction, it will be counted as EPin shortage.
                [mark_delete] => 0
                [upload_date] => 2019-10-21
            )

        [6] => Array
            (
                [store_id] => 3904
                [employee_uid] => 35818
                [opus_id] => tj539j
                [item_description] => PRE $45 PAYG PINLESS REFILL
                [opus_transaction_date] => 2019-10-20
                [opus_transaction_num] => XM1PZQSJL215F
                [opus_invoice_num] => N3904IN1410
                [customer_name] => DORTHY JONES
                [mobile_num] => 3365982631
                [opus_amount] => 90
                [rq4_amount] => 45
                [difference] => -45
                [ocomment] => Re-Upload: Please email the details to Treasury and confirm
                [mark_delete] => 0
                [upload_date] => 2019-10-21
            )

        [7] => Array
            (
                [store_id] => 1820
                [employee_uid] => 59883
                [opus_id] => cb9406
                [item_description] => PRE ATT $25 PNLS 90EXP
                [opus_transaction_date] => 2019-10-20
                [opus_transaction_num] => XTBJO14JL25OE
                [opus_invoice_num] => SEVIEIN19013
                [customer_name] => RON NELSON
                [mobile_num] => 8653821076
                [opus_amount] => 25
                [rq4_amount] => 5
                [difference] => -20
                [ocomment] => Re-Upload: We have been charged in opus for $25. Provide RQ4 invoice number for remaining amount
                [mark_delete] => 0
                [upload_date] => 2019-10-21
            )

        [8] => Array
            (
                [store_id] => 0178
                [employee_uid] => 572547
                [opus_id] => ms5674
                [item_description] => PRE $45 PAYG PINLESS REFILL
                [opus_transaction_date] => 2019-10-21
                [opus_transaction_num] => XT29916JL4S69
                [opus_invoice_num] => T0178BP1590
                [customer_name] => GABRIEL LONGORIA JR
                [mobile_num] => 4322133450
                [opus_amount] => 45
                [rq4_amount] => 0
                [difference] => -45
                [ocomment] => Re-Upload: Please email the details to Treasury and confirm
                [mark_delete] => 0
                [upload_date] => 2019-10-22
            )

        [9] => Array
            (
                [store_id] => 2180
                [employee_uid] => 7842
                [opus_id] => lm854y
                [item_description] => $30 RTR
                [opus_transaction_date] => 2019-10-21
                [opus_transaction_num] => XC9U712JL4LA4
                [opus_invoice_num] => KETERIN1836
                [customer_name] => PETE JABLONSKI
                [mobile_num] => 9374092680
                [opus_amount] => 30
                [rq4_amount] => 40
                [difference] => 10
                [ocomment] => Re-Upload: Credit the remaining balance to customers account in OPUS and email confirmation to Treasury
                [mark_delete] => 0
                [upload_date] => 2019-10-22
            )


      .
      .
      .
 [63] => Array
            (
                [store_id] => 0175
                [employee_uid] => 33738
                [opus_id] => ph5953
                [item_description] => PRE ATT $40 RTR
                [opus_transaction_date] => 2019-10-21
                [opus_transaction_num] => XE5N31DJL51RA
                [opus_invoice_num] => T0175IN4563
                [customer_name] => WILLIE TAYLOR
                [mobile_num] => 6822701188
                [opus_amount] => 40
                [rq4_amount] => 50
                [difference] => 10
                [ocomment] => Re-Upload: Credit the remaining balance to customers account in OPUS and email confirmation to Treasury
                [mark_delete] => 0
                [upload_date] => 2019-10-22
            ) 

    )

How can I download HTML source in C#

You can get it with:

var html = new System.Net.WebClient().DownloadString(siteUrl)

querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript

querySelector can be a complete CSS(3)-Selector with IDs and Classes and Pseudo-Classes together like this:

'#id.class:pseudo'

// or

'tag #id .class .class.class'

with getElementsByClassName you can just define a class

'class'

with getElementById you can just define an id

'id'

Directory.GetFiles: how to get only filename, not full path?

You can use System.IO.Path.GetFileName to do this.

E.g.,

string[] files = Directory.GetFiles(dir);
foreach(string file in files)
    Console.WriteLine(Path.GetFileName(file));

While you could use FileInfo, it is much more heavyweight than the approach you are already using (just retrieving file paths). So I would suggest you stick with GetFiles unless you need the additional functionality of the FileInfo class.

How do I get the domain originating the request in express.js?

Instead of:

var host = req.get('host');
var origin = req.get('origin');

you can also use:

var host = req.headers.host;
var origin = req.headers.origin;

java - path to trustStore - set property doesn't work?

Looks like you have a typo -- "trustStrore" should be "trustStore", i.e.

System.setProperty("javax.net.ssl.trustStrore", "cacerts.jks");

should be:

System.setProperty("javax.net.ssl.trustStore", "cacerts.jks");

Insert multiple rows WITHOUT repeating the "INSERT INTO ..." part of the statement?

You could do this (ugly but it works):

INSERT INTO dbo.MyTable (ID, Name) 
select * from
(
 select 123, 'Timmy'
  union all
 select 124, 'Jonny' 
  union all
 select 125, 'Sally'
 ...
) x