Programs & Examples On #String algorithm

BATCH file asks for file or folder

The virtual parent trick

Assuming you have your source and destination file in

%SRC_FILENAME% and %DST_FILENAME%

you could use a 2 step method:

@REM on my win 7 system mkdir creates all parent directories also
mkdir "%DST_FILENAME%\.."
xcopy "%SRC_FILENAME% "%DST_FILENAME%\.."

this would be resolved to e.g

mkdir "c:\destination\b\c\file.txt\.."
@REM The special trick here is that mkdir can create the parent
@REM directory of a "virtual" directory (c:\destination\b\c\file.txt\) that 
@REM doesn't even need to exist.
@REM So the directory "c:\destination\b\c" is created here.
@REM mkdir "c:\destination\b\c\dummystring\.." would have the same effect

xcopy "c:\source\b\c\file.txt" "c:\destination\b\c\file.txt\.."
@REM xcopy computes the real location of  "c:\destination\b\c\file.txt\.."
@REM which is the now existing directory "c:\destination\b\c"
@REM (the parent directory of the "virtual" directory c:\destination\b\c\file.txt\).

I came to the idea when I stumbled over some really wild ../..-constructs in the command lines generated from a build process.

Error: expected type-specifier before 'ClassName'

For future people struggling with a similar problem, the situation is that the compiler simply cannot find the type you are using (even if your Intelisense can find it).

This can be caused in many ways:

  • You forgot to #include the header that defines it.
  • Your inclusion guards (#ifndef BLAH_H) are defective (your #ifndef BLAH_H doesn't match your #define BALH_H due to a typo or copy+paste mistake).
  • Your inclusion guards are accidentally used twice (two separate files both using #define MYHEADER_H, even if they are in separate directories)
  • You forgot that you are using a template (eg. new Vector() should be new Vector<int>())
  • The compiler is thinking you meant one scope when really you meant another (For example, if you have NamespaceA::NamespaceB, AND a <global scope>::NamespaceB, if you are already within NamespaceA, it'll look in NamespaceA::NamespaceB and not bother checking <global scope>::NamespaceB) unless you explicitly access it.
  • You have a name clash (two entities with the same name, such as a class and an enum member).

To explicitly access something in the global namespace, prefix it with ::, as if the global namespace is a namespace with no name (e.g. ::MyType or ::MyNamespace::MyType).

How to decrease prod bundle size?

I have a angular 5 + spring boot app(application.properties 1.3+) with help of compression(link attached below) was able to reduce the size of main.bundle.ts size from 2.7 MB to 530 KB.

Also by default --aot and --build-optimizer are enabled with --prod mode you need not specify those separately.

https://stackoverflow.com/a/28216983/9491345

Difference between string and char[] types in C++

Well, string type is a completely managed class for character strings, while char[] is still what it was in C, a byte array representing a character string for you.

In terms of API and standard library everything is implemented in terms of strings and not char[], but there are still lots of functions from the libc that receive char[] so you may need to use it for those, apart from that I would always use std::string.

In terms of efficiency of course a raw buffer of unmanaged memory will almost always be faster for lots of things, but take in account comparing strings for example, std::string has always the size to check it first, while with char[] you need to compare character by character.

How can I do division with variables in a Linux shell?

To get the numbers after decimal point, you can do this:-

read num1 num2
div=`echo $num1 / $num2 | bc -l`
echo $div

Failed to add a service. Service metadata may not be accessible. Make sure your service is running and exposing metadata.`

You need to add a metadata exchange (mex) endpoint to your service:

<services>
   <service name="MyService.MyService" behaviorConfiguration="metadataBehavior">
      <endpoint 
          address="http://localhost/MyService.svc" 
          binding="customBinding" bindingConfiguration="jsonpBinding" 
          behaviorConfiguration="MyService.MyService"
          contract="MyService.IMyService"/>
      <endpoint 
          address="mex" 
          binding="mexHttpBinding" 
          contract="IMetadataExchange"/>
   </service>
</services>

Now, you should be able to get metadata for your service

Update: ok, so you're just launching this from Visual Studio - in that case, it will be hosted in Cassini, the built-in web server. That beast however only supports HTTP - you're not using that protocol in your binding...

Also, since you're hosting this in Cassini, the address of your service will be dictated by Cassini - you don't get to define anything.

So my suggestion would be:

  • try to use http binding (just now for testing)
  • get this to work
  • once you know it works, change it to your custom binding and host it in IIS

So I would change the config to:

<behaviors>
   <serviceBehaviors>
      <behavior name="metadataBehavior">
         <serviceMetadata httpGetEnabled="true" />
      </behavior>
   </serviceBehaviors>
</behaviors>
<services>
   <service name="MyService.MyService" behaviorConfiguration="metadataBehavior">
      <endpoint 
          address=""   <!-- don't put anything here - Cassini will determine address -->
          binding="basicHttpBinding" 
          contract="MyService.IMyService"/>
      <endpoint 
          address="mex" 
          binding="mexHttpBinding" 
          contract="IMetadataExchange"/>
   </service>
</services>

Once you have that, try to do a View in Browser on your SVC file in your Visual Studio solution - if that doesn't work, you still have a major problem of some sort.

If it works - now you can press F5 in VS and your service should come up, and using the WCF Test Client app, you should be able to get your service metadata from a) the address that Cassini started your service on, or b) the mex address (Cassini's address + /mex)

How to call Makefile from another Makefile?

It seems clear that $(TESTS) is empty so your 1.4.0 makefile is effectively

all: 

clean:
  rm -f  gtest.a gtest_main.a *.o

Indeed, all has nothing to do. and clean does exactly what it says rm -f gtest.a ...

How to have a drop down <select> field in a rails form?

Please have a look here

Either you can use rails tag Or use plain HTML tags

Rails tag

<%= select("Contact", "email_provider", Contact::PROVIDERS, {:include_blank => true}) %>

*above line of code would become HTML code(HTML Tag), find it below *

HTML tag

<select name="Contact[email_provider]">
  <option></option>
  <option>yahoo</option>
  <option>gmail</option>
  <option>msn</option>
</select>

Spring Boot how to hide passwords in properties file

In case you are using quite popular in Spring Boot environment Kubernetes (K8S) or OpenShift, there's a possibility to store and retrieve application properties on runtime. This technique called secrets. In your configuration yaml file for Kubernetes or OpenShift you declare variable and placeholder for it, and on K8S\OpenShift side declare actual value which corresponds to this placeholder. For implementation details, see: K8S: https://kubernetes.io/docs/concepts/configuration/secret/ OpenShift: https://docs.openshift.com/container-platform/3.11/dev_guide/secrets.html

How to check that Request.QueryString has a specific value or not in ASP.NET?

You can just check for null:

if(Request.QueryString["aspxerrorpath"]!=null)
{
   //your code that depends on aspxerrorpath here
}

How do you read scanf until EOF in C?

You need to check the return value against EOF, not against 1.

Note that in your example, you also used two different variable names, words and word, only declared words, and didn't declare its length, which should be 16 to fit the 15 characters read in plus a NUL character.

Understanding passport serialize deserialize

For anyone using Koa and koa-passport:

Know that the key for the user set in the serializeUser method (often a unique id for that user) will be stored in:

this.session.passport.user

When you set in done(null, user) in deserializeUser where 'user' is some user object from your database:

this.req.user OR this.passport.user

for some reason this.user Koa context never gets set when you call done(null, user) in your deserializeUser method.

So you can write your own middleware after the call to app.use(passport.session()) to put it in this.user like so:

app.use(function * setUserInContext (next) {
  this.user = this.req.user
  yield next
})

If you're unclear on how serializeUser and deserializeUser work, just hit me up on twitter. @yvanscher

how to bind img src in angular 2 in ngFor?

Angular 2 and Angular 4 

In a ngFor loop it must be look like this:

<div class="column" *ngFor="let u of events ">
                <div class="thumb">
                    <img src="assets/uploads/{{u.image}}">
                    <h4>{{u.name}}</h4>
                </div>
                <div class="info">
                    <img src="assets/uploads/{{u.image}}">
                    <h4>{{u.name}}</h4>
                    <p>{{u.text}}</p>
                </div>
            </div>

How can I make Java print quotes, like "Hello"?

System.out.println("\"Hello\""); 

problem with <select> and :after with CSS in WebKit

This post may help http://bavotasan.com/2011/style-select-box-using-only-css/

He is using a outside div with a class for resolving this issue.

<div class="styled-select">
  <select>
    <option>Here is the first option</option>
    <option>The second option</option>
  </select>
</div>

Get full query string in C# ASP.NET

I have tested your example, and while Request.QueryString is not convertible to a string neither implicit nor explicit still the .ToString() method returns the correct result.

Further more when concatenating with a string using the "+" operator as in your example it will also return the correct result (because this behaves as if .ToString() was called).

As such there is nothing wrong with your code, and I would suggest that your issue was because of a typo in your code writing "Querystring" instead of "QueryString".

And this makes more sense with your error message since if the problem is that QueryString is a collection and not a string it would have to give another error message.

How to get mouse position in jQuery without mouse-events?

I don't believe there's a way to query the mouse position, but you can use a mousemove handler that just stores the information away, so you can query the stored information.

jQuery(function($) {
    var currentMousePos = { x: -1, y: -1 };
    $(document).mousemove(function(event) {
        currentMousePos.x = event.pageX;
        currentMousePos.y = event.pageY;
    });

    // ELSEWHERE, your code that needs to know the mouse position without an event
    if (currentMousePos.x < 10) {
        // ....
    }
});

But almost all code, other than setTimeout code and such, runs in response to an event, and most events provide the mouse position. So your code that needs to know where the mouse is probably already has access to that information...

Change a Nullable column to NOT NULL with Default Value

Try this

ALTER TABLE table_name ALTER COLUMN col_name data_type NOT NULL;

Iterate through DataSet

Just loop...

foreach(var table in DataSet1.Tables) {
    foreach(var col in table.Columns) {
       ...
    }
    foreach(var row in table.Rows) {
        object[] values = row.ItemArray;
        ...
    }
}

Python - How to concatenate to a string in a for loop?

This should work:

endstring = ''.join(list)

CSS hide scroll bar, but have element scrollable

if you use sass, you can try this

&::-webkit-scrollbar { 

}

Your password does not satisfy the current policy requirements

In my opinion setting the "validate_password_policy" to "low" or uninstalling the "validate password plugin" is not the right thing to do. You must never compromise with security of your database (unless you don't really care). I am wondering why people are even suggesting these options when you simply can pick a good password.

To overcome this problem, I executed following command in mysql: SHOW VARIABLES LIKE 'validate_password%' as suggested by @JNevill. My "validate_password_policy" was set to Medium, along with other things. Here is the screenshot of its execution: Validate Password Policy

The result is self explanatory. For a valid password (when Password policy is set to medium):

  • Password must be at least 8 characters long
  • Mixed case count is 1 (At least 1 letter in small and 1 letter in caps)
  • Number count is 1
  • Minimum special Character count is 1

So a valid password must obey the policy. Examples of valid password for above rules maybe:

  • Student123@
  • NINZAcoder$100
  • demoPass#00

You can pick any combination as long as it satisfies the policy.

For other "validate_password_policy" you can simply look the values for different options and pick your password accordingly (I haven't tried for "STRONG").

https://dev.mysql.com/doc/refman/5.6/en/validate-password-options-variables.html

drag drop files into standard html file input

This is an improvement, bugfix, and modification of the example that William Entriken gave here. There were some issues with it. For example the normal button from <input type="file" /> didn't do anything (in case the user wanted to upload the file that way).

Notice: I am making a webapp that only I use, so this is only tested (and refined) for Firefox. I am sure though that this code is of value even if you develop for the crossbrowser situation.

_x000D_
_x000D_
function readFile(e) {
  var files;
  if (e.target.files) {
    files=e.target.files
  } else {
    files=e.dataTransfer.files
  }
  if (files.length==0) {
    alert('What you dropped is not a file.');
    return;
  }
  var file=files[0];
  document.getElementById('fileDragName').value = file.name
  document.getElementById('fileDragSize').value = file.size
  document.getElementById('fileDragType').value = file.type
  reader = new FileReader();
  reader.onload = function(e) {
    document.getElementById('fileDragData').value = e.target.result;
  }
  reader.readAsDataURL(file);
}
function getTheFile(e) {
  e.target.style.borderColor='#ccc';
  readFile(e);
}
_x000D_
<input type="file" onchange="readFile(event)">
<input id="fileDragName">
<input id="fileDragSize">
<input id="fileDragType">
<input id="fileDragData">
<div style="width:200px; height:200px; border: 10px dashed #ccc"
     ondragover="this.style.borderColor='#0c0';return false;"       
     ondragleave="this.style.borderColor='#ccc'"       
     ondrop="getTheFile(event); return false;"       
></div>
_x000D_
_x000D_
_x000D_

Changing image size in Markdown

You could just use some HTML in your Markdown:

<img src="drawing.jpg" alt="drawing" width="200"/>

Or via style attribute (not supported by GitHub)

<img src="drawing.jpg" alt="drawing" style="width:200px;"/>

Or you could use a custom CSS file as described in this answer on Markdown and image alignment

![drawing](drawing.jpg)

CSS in another file:

img[alt=drawing] { width: 200px; }

Get individual query parameters from Uri

I had to do this for a modern windows app. I used the following:

public static class UriExtensions
{
    private static readonly Regex _regex = new Regex(@"[?&](\w[\w.]*)=([^?&]+)");

    public static IReadOnlyDictionary<string, string> ParseQueryString(this Uri uri)
    {
        var match = _regex.Match(uri.PathAndQuery);
        var paramaters = new Dictionary<string, string>();
        while (match.Success)
        {
            paramaters.Add(match.Groups[1].Value, match.Groups[2].Value);
            match = match.NextMatch();
        }
        return paramaters;
    }
}

update query with join on two tables

Officially, the SQL languages does not support a JOIN or FROM clause in an UPDATE statement unless it is in a subquery. Thus, the Hoyle ANSI approach would be something like

Update addresses
Set cid = (
            Select c.id
            From customers As c
            where c.id = a.id
            )
Where Exists    (
                Select 1
                From customers As C1
                Where C1.id = addresses.id
                )

However many DBMSs such Postgres support the use of a FROM clause in an UPDATE statement. In many cases, you are required to include the updating table and alias it in the FROM clause however I'm not sure about Postgres:

Update addresses
Set cid = c.id
From addresses As a
    Join customers As c
        On c.id = a.id

Set database from SINGLE USER mode to MULTI USER

I actually had an issue where my db was pretty much locked by the processes and a race condition with them, by the time I got one command executed refreshed and they had it locked again... I had to run the following commands back to back in SSMS and got me offline and from there I did my restore and came back online just fine, the two queries where:

First ran:

USE master
GO

DECLARE @kill varchar(8000) = '';
SELECT @kill = @kill + 'kill ' + CONVERT(varchar(5), spid) + ';'
FROM master..sysprocesses 
WHERE dbid = db_id('<yourDbName>')

EXEC(@kill);

Then immediately after (in second query window):

USE master ALTER DATABASE <yourDbName> SET OFFLINE WITH ROLLBACK IMMEDIATE

Did what I needed and then brought it back online. Thanks to all who wrote these pieces out for me to combine and solve my problem.

Random color generator

So whilst all the answers here are good I wanted a bit more control over the output. For instance I'd like to prevent any near white shades, whilst ensuring I get bright vibrant colours not washed out shades.

function generateColor(ranges) {
            if (!ranges) {
                ranges = [
                    [150,256],
                    [0, 190],
                    [0, 30]
                ];
            }
            var g = function() {
                //select random range and remove
                var range = ranges.splice(Math.floor(Math.random()*ranges.length), 1)[0];
                //pick a random number from within the range
                return Math.floor(Math.random() * (range[1] - range[0])) + range[0];
            }
            return "rgb(" + g() + "," + g() + "," + g() +")";
        };

So now I can specify 3 arbitrary ranges to pick rgb values from. You can call it with no arguments and get my default set which will usually generate a quite vibrant colour with once obvious dominant shade, or you can supply your own array of ranges.

Package name does not correspond to the file path - IntelliJ

I created a package under folder src which resolved this problem.

project structure

Get GPS location via a service in Android

I don't understand what exactly is the problem with implementing location listening functionality in the Service. It looks pretty similar to what you do in Activity. Just define a location listener and register for location updates. You can refer to the following code as example:

Manifest file:

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name" >
    <activity android:label="@string/app_name" android:name=".LocationCheckerActivity" >
        <intent-filter >
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <service android:name=".MyService" android:process=":my_service" />
</application>

The service file:

import android.app.Service;
import android.content.Context;
import android.content.Intent;
import android.location.Location;
import android.location.LocationManager;
import android.os.Bundle;
import android.os.IBinder;
import android.util.Log;

public class MyService extends Service {

    private static final String TAG = "BOOMBOOMTESTGPS";
    private LocationManager mLocationManager = null;
    private static final int LOCATION_INTERVAL = 1000;
    private static final float LOCATION_DISTANCE = 10f;

    private class LocationListener implements android.location.LocationListener {
        Location mLastLocation;

        public LocationListener(String provider) {
            Log.e(TAG, "LocationListener " + provider);
            mLastLocation = new Location(provider);
        }

        @Override
        public void onLocationChanged(Location location) {
            Log.e(TAG, "onLocationChanged: " + location);
            mLastLocation.set(location);
        }

        @Override
        public void onProviderDisabled(String provider) {
            Log.e(TAG, "onProviderDisabled: " + provider);
        }

        @Override
        public void onProviderEnabled(String provider) {
            Log.e(TAG, "onProviderEnabled: " + provider);
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
            Log.e(TAG, "onStatusChanged: " + provider);
        }
    }

    LocationListener[] mLocationListeners = new LocationListener[]{
            new LocationListener(LocationManager.GPS_PROVIDER),
            new LocationListener(LocationManager.NETWORK_PROVIDER)
    };

    @Override
    public IBinder onBind(Intent arg0) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.e(TAG, "onStartCommand");
        super.onStartCommand(intent, flags, startId);
        return START_STICKY;
    }

    @Override
    public void onCreate() {
        Log.e(TAG, "onCreate");
        initializeLocationManager();
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[1]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "network provider does not exist, " + ex.getMessage());
        }
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[0]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "gps provider does not exist " + ex.getMessage());
        }
    }

    @Override
    public void onDestroy() {
        Log.e(TAG, "onDestroy");
        super.onDestroy();
        if (mLocationManager != null) {
            for (int i = 0; i < mLocationListeners.length; i++) {
                try {
                    mLocationManager.removeUpdates(mLocationListeners[i]);
                } catch (Exception ex) {
                    Log.i(TAG, "fail to remove location listners, ignore", ex);
                }
            }
        }
    }

    private void initializeLocationManager() {
        Log.e(TAG, "initializeLocationManager");
        if (mLocationManager == null) {
            mLocationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
        }
    }
}

PDOException SQLSTATE[HY000] [2002] No such file or directory

In may case, I'd simply used

vagrant up

instead of

homestead up

for my forge larval setup using homestead. I'm assuming this meant the site was getting served, but the MySQL server wasn't ever booted. When I used the latter command to launch my vagrant box, the error went away.

Renaming files using node.js

You'll need to use fs for that: http://nodejs.org/api/fs.html

And in particular the fs.rename() function:

var fs = require('fs');
fs.rename('/path/to/Afghanistan.png', '/path/to/AF.png', function(err) {
    if ( err ) console.log('ERROR: ' + err);
});

Put that in a loop over your freshly-read JSON object's keys and values, and you've got a batch renaming script.

fs.readFile('/path/to/countries.json', function(error, data) {
    if (error) {
        console.log(error);
        return;
    }

    var obj = JSON.parse(data);
    for(var p in obj) {
        fs.rename('/path/to/' + obj[p] + '.png', '/path/to/' + p + '.png', function(err) {
            if ( err ) console.log('ERROR: ' + err);
        });
    }
});

(This assumes here that your .json file is trustworthy and that it's safe to use its keys and values directly in filenames. If that's not the case, be sure to escape those properly!)

angular2 submit form by pressing enter without submit button

If you want to include both - accept on enter and accept on click then do -

 <div class="form-group">
    <input class="form-control"   type="text" 
    name="search" placeholder="Enter Search Text"
              [(ngModel)]="filterdata"  
           (keyup.enter)="searchByText(filterdata)">
  <button type="submit"  
          (click)="searchByText(filterdata)" >

  </div>

Python Pip install Error: Unable to find vcvarsall.bat. Tried all solutions

Try installing this, it's a known workaround for enabling the C++ compiler for Python 2.7.

In my experience, when pip does not find vcvarsall.bat compiler, all I do is opening a Visual Studio console as it set the path variables to call vcvarsall.bat directly and then I run pip on this command line.

Convert PDF to PNG using ImageMagick

Reducing the image size before output results in something that looks sharper, in my case:

convert -density 300 a.pdf -resize 25% a.png

Java Code for calculating Leap Year

public static void main(String[] args)
{

String strDate="Feb 2013";
        String[] strArray=strDate.split("\\s+");        

        Calendar cal = Calendar.getInstance();
        cal.setTime(new SimpleDateFormat("MMM").parse(strArray[0].toString()));
        int monthInt = cal.get(Calendar.MONTH);
        monthInt++;
        cal.set(Calendar.YEAR, Integer.parseInt(strArray[1]));          
        strDate=strArray[1].toString()+"-"+monthInt+"-"+cal.getActualMaximum(Calendar.DAY_OF_MONTH);

        System.out.println(strDate);    



}

How do I remove all null and empty string values from an object?

There is a very simple way to remove NULL values from JSON object. By default JSON object includes NULL values. Following can be used to remove NULL from JSON string

JsonConvert.SerializeObject(yourClassObject, new JsonSerializerSettings() {
                                       NullValueHandling = NullValueHandling.Ignore})) 

SQL Server: combining multiple rows into one row

There's a convenient method for this in MySql called GROUP_CONCAT. An equivalent for SQL Server doesn't exist, but you can write your own using the SQLCLR. Luckily someone already did that for you.

Your query then turns into this (which btw is a much nicer syntax):

SELECT CUSTOMFIELD, ISSUE, dbo.GROUP_CONCAT(STRINGVALUE)
FROM Jira.customfieldvalue
WHERE CUSTOMFIELD = 12534 AND ISSUE = 19602
GROUP BY CUSTOMFIELD, ISSUE

But please note that this method is good for at the most 100 rows within a group. Beyond that, you'll have major performance problems. SQLCLR aggregates have to serialize any intermediate results and that quickly piles up to quite a lot of work. Keep this in mind!

Interestingly the FOR XML doesn't suffer from the same problem but instead uses that horrendous syntax.

Conflict with dependency 'com.android.support:support-annotations' in project ':app'. Resolved versions for app (26.1.0) and test app (27.1.1) differ.

Important Update

Go to project level build.gradle, define global variables

// Top-level build file where you can add configuration options common to all sub-projects/modules.

buildscript {
    ext.kotlinVersion = '1.2.61'

    ext.global_minSdkVersion = 16
    ext.global_targetSdkVersion = 28
    ext.global_buildToolsVersion = '28.0.1'
    ext.global_supportLibVersion = '27.1.1'
}

Go to app level build.gradle, and use global variables

app build.gradle

android {
    compileSdkVersion global_targetSdkVersion
    buildToolsVersion global_buildToolsVersion
    defaultConfig {
        minSdkVersion global_minSdkVersion
        targetSdkVersion global_targetSdkVersion
}
...

dependencies {
    implementation "com.android.support:appcompat-v7:$global_supportLibVersion"
    implementation "com.android.support:recyclerview-v7:$global_supportLibVersion"
    // and so on...
}

some library build.gradle

android {
    compileSdkVersion global_targetSdkVersion
    buildToolsVersion global_buildToolsVersion
    defaultConfig {
        minSdkVersion global_minSdkVersion
        targetSdkVersion global_targetSdkVersion
}
...

dependencies {
    implementation "com.android.support:appcompat-v7:$global_supportLibVersion"
    implementation "com.android.support:recyclerview-v7:$global_supportLibVersion"
    // and so on...
}

The solution is to make your versions same as in all modules. So that you don't have conflicts.

Important Tips

I felt when I have updated versions of everything- gradle, sdks, libraries etc. then I face less errors. Because developers are working hard to make it easy development on Android Studio.

Always have latest but stable versions Unstable versions are alpha, beta and rc, ignore them in developing.

I have updated all below in my projects, and I don't face these errors anymore.

Happy coding! :)

Determine function name from within that function (without using traceback)

This is pretty easy to accomplish with a decorator.

>>> from functools import wraps

>>> def named(func):
...     @wraps(func)
...     def _(*args, **kwargs):
...         return func(func.__name__, *args, **kwargs)
...     return _
... 

>>> @named
... def my_func(name, something_else):
...     return name, something_else
... 

>>> my_func('hello, world')
('my_func', 'hello, world')

c# replace \" characters

In .NET Framework 4 and MVC this is the only representation that worked:

Replace(@"""","")

Using a backslash in whatever combination did not work...

jquery can't get data attribute value

Use plain javascript methods

$x10Device = this.dataset("x10");

How to Create an excel dropdown list that displays text with a numeric hidden value

Data validation drop down

There is a list option in Data validation. If this is combined with a VLOOKUP formula you would be able to convert the selected value into a number.

The steps in Excel 2010 are:

  • Create your list with matching values.
  • On the Data tab choose Data Validation
  • The Data validation form will be displayed
  • Set the Allow dropdown to List
  • Set the Source range to the first part of your list
  • Click on OK (User messages can be added if required)

In a cell enter a formula like this

=VLOOKUP(A2,$D$3:$E$5,2,FALSE)

which will return the matching value from the second part of your list.

Screenshot of Data validation list

Form control drop down

Alternatively, Form controls can be placed on a worksheet. They can be linked to a range and return the position number of the selected value to a specific cell.

The steps in Excel 2010 are:

  • Create your list of data in a worksheet
  • Click on the Developer tab and dropdown on the Insert option
  • In the Form section choose Combo box or List box
  • Use the mouse to draw the box on the worksheet
  • Right click on the box and select Format control
  • The Format control form will be displayed
  • Click on the Control tab
  • Set the Input range to your list of data
  • Set the Cell link range to the cell where you want the number of the selected item to appear
  • Click on OK

Screenshot of form control

Redefine tab as 4 spaces

There are few settings which define whether to use spaces or tabs.

So here are handy functions which can be defined in your ~/.vimrc file:

function! UseTabs()
  set tabstop=4     " Size of a hard tabstop (ts).
  set shiftwidth=4  " Size of an indentation (sw).
  set noexpandtab   " Always uses tabs instead of space characters (noet).
  set autoindent    " Copy indent from current line when starting a new line (ai).
endfunction

function! UseSpaces()
  set tabstop=2     " Size of a hard tabstop (ts).
  set shiftwidth=2  " Size of an indentation (sw).
  set expandtab     " Always uses spaces instead of tab characters (et).
  set softtabstop=0 " Number of spaces a <Tab> counts for. When 0, featuer is off (sts).
  set autoindent    " Copy indent from current line when starting a new line.
  set smarttab      " Inserts blanks on a <Tab> key (as per sw, ts and sts).
endfunction

Usage:

:call UseTabs()
:call UseSpaces()

To use it per file extensions, the following syntax can be used (added to .vimrc):

au! BufWrite,FileWritePre *.module,*.install call UseSpaces()

See also: Converting tabs to spaces.


Here is another snippet from Wikia which can be used to toggle between tabs and spaces:

" virtual tabstops using spaces
set shiftwidth=4
set softtabstop=4
set expandtab
" allow toggling between local and default mode
function TabToggle()
  if &expandtab
    set shiftwidth=8
    set softtabstop=0
    set noexpandtab
  else
    set shiftwidth=4
    set softtabstop=4
    set expandtab
  endif
endfunction
nmap <F9> mz:execute TabToggle()<CR>'z

It enables using 4 spaces for every tab and a mapping to F9 to toggle the settings.

Download image with JavaScript

As @Ian explained, the problem is that jQuery's click() is not the same as the native one.

Therefore, consider using vanilla-js instead of jQuery:

var a = document.createElement('a');
a.href = "img.png";
a.download = "output.png";
document.body.appendChild(a);
a.click();
document.body.removeChild(a);

Demo

How to launch an application from a browser?

Some applications launches themselves by protocols. like itunes with "itms://" links. I don't know however how you can register that with windows.

Android: disabling highlight on listView click

For me android:focusableInTouchMode="true" is the way to go. android:listSelector="@android:color/transparent" is of no use. Note that I am using a custom listview with a number of objects in each row.

How to create JSON Object using String?

JSONArray may be what you want.

String message;
JSONObject json = new JSONObject();
json.put("name", "student");

JSONArray array = new JSONArray();
JSONObject item = new JSONObject();
item.put("information", "test");
item.put("id", 3);
item.put("name", "course1");
array.put(item);

json.put("course", array);

message = json.toString();

// message
// {"course":[{"id":3,"information":"test","name":"course1"}],"name":"student"}

Are there any standard exit status codes in Linux?

To a first approximation, 0 is success, non-zero is failure, with 1 being general failure, and anything larger than one being a specific failure. Aside from the trivial exceptions of false and test, which are both designed to give 1 for success, there's a few other exceptions I found.

More realistically, 0 means success or maybe failure, 1 means general failure or maybe success, 2 means general failure if 1 and 0 are both used for success, but maybe sucess as well.

The diff command gives 0 if files compared are identical, 1 if they differ, and 2 if binaries are different. 2 also means failure. The less command gives 1 for failure unless you fail to supply an argument, in which case, it exits 0 despite failing.

The more command and the spell command give 1 for failure, unless the failure is a result of permission denied, nonexistent file, or attempt to read a directory. In any of these cases, they exit 0 despite failing.

Then the expr command gives 1 for success unless the output is the empty string or zero, in which case, 0 is success. 2 and 3 are failure.

Then there's cases where success or failure is ambiguous. When grep fails to find a pattern, it exits 1, but it exits 2 for a genuine failure (like permission denied). Klist also exits 1 when it fails to find a ticket, although this isn't really any more of a failure than when grep doesn't find a pattern, or when you ls an empty directory.

So, unfortunately, the unix powers that be don't seem to enforce any logical set of rules, even on very commonly used executables.

Rendering an array.map() in React

Add up to Dmitry's answer, if you don't want to handle unique key IDs manually, you can use React.Children.toArray as proposed in the React documentation

React.Children.toArray

Returns the children opaque data structure as a flat array with keys assigned to each child. Useful if you want to manipulate collections of children in your render methods, especially if you want to reorder or slice this.props.children before passing it down.

Note:

React.Children.toArray() changes keys to preserve the semantics of nested arrays when flattening lists of children. That is, toArray prefixes each key in the returned array so that each element’s key is scoped to the input array containing it.

 <div>
    <ul>
      {
        React.Children.toArray(
          this.state.data.map((item, i) => <li>Test</li>)
        )
      }
    </ul>
  </div>

How to force a component's re-rendering in Angular 2?

tx, found the workaround I needed:

  constructor(private zone:NgZone) {
    // enable to for time travel
    this.appStore.subscribe((state) => {
        this.zone.run(() => {
            console.log('enabled time travel');
        });
    });

running zone.run will force the component to re-render

How to sort the letters in a string alphabetically in Python

You can use reduce

>>> a = 'ZENOVW'
>>> reduce(lambda x,y: x+y, sorted(a))
'ENOVWZ'

Android Studio Stuck at Gradle Download on create new project

I had fixed this problem by removing the .gradle folder

in windows: C:\Users{Logged in User}.gradle

Sending HTTP POST with System.Net.WebClient

Based on @carlosfigueira 's answer, I looked further into WebClient's methods and found UploadValues, which is exactly what I want:

Using client As New Net.WebClient
    Dim reqparm As New Specialized.NameValueCollection
    reqparm.Add("param1", "somevalue")
    reqparm.Add("param2", "othervalue")
    Dim responsebytes = client.UploadValues(someurl, "POST", reqparm)
    Dim responsebody = (New Text.UTF8Encoding).GetString(responsebytes)
End Using

The key part is this:

client.UploadValues(someurl, "POST", reqparm)

It sends whatever verb I type in, and it also helps me create a properly url encoded form data, I just have to supply the parameters as a namevaluecollection.

Which comment style should I use in batch files?

Comments with REM

A REM can remark a complete line, also a multiline caret at the line end, if it's not the end of the first token.

REM This is a comment, the caret is ignored^
echo This line is printed

REM This_is_a_comment_the_caret_appends_the_next_line^
echo This line is part of the remark

REM followed by some characters .:\/= works a bit different, it doesn't comment an ampersand, so you can use it as inline comment.

echo First & REM. This is a comment & echo second

But to avoid problems with existing files like REM, REM.bat or REM;.bat only a modified variant should be used.

REM^;<space>Comment

And for the character ; is also allowed one of ;,:\/=

REM is about 6 times slower than :: (tested on Win7SP1 with 100000 comment lines).
For a normal usage it's not important (58µs versus 360µs per comment line)

Comments with ::

A :: always executes a line end caret.

:: This is also a comment^
echo This line is also a comment

Labels and also the comment label :: have a special logic in parenthesis blocks.
They span always two lines SO: goto command not working.
So they are not recommended for parenthesis blocks, as they are often the cause for syntax errors.

With ECHO ON a REM line is shown, but not a line commented with ::

Both can't really comment out the rest of the line, so a simple %~ will cause a syntax error.

REM This comment will result in an error %~ ...

But REM is able to stop the batch parser at an early phase, even before the special character phase is done.

@echo ON
REM This caret ^ is visible

You can use &REM or &:: to add a comment to the end of command line. This approach works because '&' introduces a new command on the same line.

Comments with percent signs %= comment =%

There exists a comment style with percent signs.

In reality these are variables but they are expanded to nothing.
But the advantage is that they can be placed in the same line, even without &.
The equal sign ensures, that such a variable can't exists.

echo Mytest
set "var=3"     %= This is a comment in the same line=%

The percent style is recommended for batch macros, as it doesn't change the runtime behaviour, as the comment will be removed when the macro is defined.

set $test=(%\n%
%=Start of code=% ^
echo myMacro%\n%
)

Sorting hashmap based on keys

Use sorted TreeMap:

Map<String, Float> map = new TreeMap<>(yourMap);

It will automatically put entries sorted by keys. I think natural String ordering will be fine in your case.

Note that HashMap due to lookup optimizations does not preserve order.

Scroll to element on click in Angular 4

You can achieve that by using the reference to an angular DOM element as follows:

Here is the example in stackblitz

the component template:

<div class="other-content">
      Other content
      <button (click)="element.scrollIntoView({ behavior: 'smooth', block: 'center' })">
        Click to scroll
      </button>
    </div>
    <div id="content" #element>
      Some text to scroll
</div>

What is the difference between children and childNodes in JavaScript?

Pick one depends on the method you are looking for!?

I will go with ParentNode.children:

As it provides namedItem method that allows me directly to get one of the children elements without looping through all children or avoiding to use getElementById etc.

e.g.

ParentNode.children.namedItem('ChildElement-ID'); // JS
ref.current.children.namedItem('ChildElement-ID'); // React
this.$refs.ref.children.namedItem('ChildElement-ID'); // Vue

I will go with Node.childNodes:

As it provides forEach method when I work with window.IntersectionObserver e.g.

nodeList.forEach((node) => { observer.observe(node) })
// IE11 does not support forEach on nodeList, but easy to be polyfilled.

On Chrome 83

Node.childNodes provides entries, forEach, item, keys, length and values

ParentNode.children provides item, length and namedItem

Firebase FCM notifications click_action payload

If your app is in background, Firebase will not trigger onMessageReceived(). Why.....? I have no idea. In this situation, I do not see any point in implementing FirebaseMessagingService.

According to docs, if you want to process background message arrival, you have to send 'click_action' with your message. But it is not possible if you send message from Firebase console, only via Firebase API. It means you will have to build your own "console" in order to enable marketing people to use it. So, this makes Firebase console also quite useless!

There is really good, promising, idea behind this new tool, but executed badly.

I suppose we will have to wait for new versions and improvements/fixes!

SQL Server date format yyyymmdd

You can do as follows:

Select Format(test.Time, 'yyyyMMdd')
From TableTest test

How to position three divs in html horizontally?

I know this is a very old question. Just posting this here as I solved this problem using FlexBox. Here is the solution

_x000D_
_x000D_
#container {
  height: 100%;
  width: 100%;
  display: flex;
}
#leftThing {
  width: 25%;
  background-color: blue;
}
#content {
  width: 50%;
  background-color: green;
}
#rightThing {
  width: 25%;
  background-color: yellow;
}
_x000D_
<div id="container">

  <div id="leftThing">
    Left Side Menu
  </div>

  <div id="content">
    Random Content
  </div>

  <div id="rightThing">
    Right Side Menu
  </div>

</div>
_x000D_
_x000D_
_x000D_

Just had to add display:flex to the container! No floats required.

SQL MERGE statement to update data

I often used Bacon Bits great answer as I just can not memorize the syntax.

But I usually add a CTE as an addition to make the DELETE part more useful because very often you will want to apply the merge only to a part of the target table.

WITH target as (
    SELECT * FROM dbo.energydate WHERE DateTime > GETDATE()
)
MERGE INTO target WITH (HOLDLOCK)
USING dbo.temp_energydata AS source
    ON target.webmeterID = source.webmeterID
    AND target.DateTime = source.DateTime
WHEN MATCHED THEN 
    UPDATE SET target.kWh = source.kWh
WHEN NOT MATCHED BY TARGET THEN
    INSERT (webmeterID, DateTime, kWh)
    VALUES (source.webmeterID, source.DateTime, source.kWh)
WHEN NOT MATCHED BY SOURCE THEN
    DELETE

<hr> tag in Twitter Bootstrap not functioning correctly?

the css property of <hr> are :

hr {
  -moz-border-bottom-colors: none;
  -moz-border-image: none;
  -moz-border-left-colors: none;
  -moz-border-right-colors: none;
  -moz-border-top-colors: none;
  border-color: #EEEEEE -moz-use-text-color #FFFFFF;
  border-style: solid none;
  border-width: 1px 0;
  margin: 18px 0;
}

It correspond to a 1px horizontal line with a very light grey and vertical margin of 18px.

and because <hr> is inside a <div> without class the width depends on the content of the <div>

if you would like the <hr> to be full width, replace <div> with <div class='row'><div class='span12'> (with according closing tags).

If you expect something different, describe what you expect by adding a comment.

What is the difference between a cer, pvk, and pfx file?

Windows uses .cer extension for an X.509 certificate. These can be in "binary" (ASN.1 DER), or it can be encoded with Base-64 and have a header and footer applied (PEM); Windows will recognize either. To verify the integrity of a certificate, you have to check its signature using the issuer's public key... which is, in turn, another certificate.

Windows uses .pfx for a PKCS #12 file. This file can contain a variety of cryptographic information, including certificates, certificate chains, root authority certificates, and private keys. Its contents can be cryptographically protected (with passwords) to keep private keys private and preserve the integrity of root certificates.

Windows uses .pvk for a private key file. I'm not sure what standard (if any) Windows follows for these. Hopefully they are PKCS #8 encoded keys. Emmanuel Bourg reports that these are a proprietary format. Some documentation is available.

You should never disclose your private key. These are contained in .pfx and .pvk files.

Generally, you only exchange your certificate (.cer) and the certificates of any intermediate issuers (i.e., the certificates of all of your CAs, except the root CA) with other parties.

Create Directory if it doesn't exist with Ruby

How about just Dir.mkdir('dir') rescue nil ?

Converting 'ArrayList<String> to 'String[]' in Java

If your application is already using Apache Commons lib, you can slightly modify the accepted answer to not create a new empty array each time:

List<String> list = ..;
String[] array = list.toArray(ArrayUtils.EMPTY_STRING_ARRAY);

// or if using static import
String[] array = list.toArray(EMPTY_STRING_ARRAY);

There are a few more preallocated empty arrays of different types in ArrayUtils.

Also we can trick JVM to create en empty array for us this way:

String[] array = list.toArray(ArrayUtils.toArray());

// or if using static import
String[] array = list.toArray(toArray());

But there's really no advantage this way, just a matter of taste, IMO.

String length in bytes in JavaScript

This would work for BMP and SIP/SMP characters.

    String.prototype.lengthInUtf8 = function() {
        var asciiLength = this.match(/[\u0000-\u007f]/g) ? this.match(/[\u0000-\u007f]/g).length : 0;
        var multiByteLength = encodeURI(this.replace(/[\u0000-\u007f]/g)).match(/%/g) ? encodeURI(this.replace(/[\u0000-\u007f]/g, '')).match(/%/g).length : 0;
        return asciiLength + multiByteLength;
    }

    'test'.lengthInUtf8();
    // returns 4
    '\u{2f894}'.lengthInUtf8();
    // returns 4
    '???? ?????'.lengthInUtf8();
    // returns 19, each Arabic/Persian alphabet character takes 2 bytes. 
    '??,JavaScript ??'.lengthInUtf8();
    // returns 26, each Chinese character/punctuation takes 3 bytes. 

How to merge 2 JSON objects from 2 files using jq?

Since 1.4 this is now possible with the * operator. When given two objects, it will merge them recursively. For example,

jq -s '.[0] * .[1]' file1 file2

Important: Note the -s (--slurp) flag, which puts files in the same array.

Would get you:

{
  "value1": 200,
  "timestamp": 1382461861,
  "value": {
    "aaa": {
      "value1": "v1",
      "value2": "v2",
      "value3": "v3",
      "value4": 4
    },
    "bbb": {
      "value1": "v1",
      "value2": "v2",
      "value3": "v3"
    },
    "ccc": {
      "value1": "v1",
      "value2": "v2"
    },
    "ddd": {
      "value3": "v3",
      "value4": 4
    }
  },
  "status": 200
}

If you also want to get rid of the other keys (like your expected result), one way to do it is this:

jq -s '.[0] * .[1] | {value: .value}' file1 file2

Or the presumably somewhat more efficient (because it doesn't merge any other values):

jq -s '.[0].value * .[1].value | {value: .}' file1 file2

Interface vs Abstract Class (general OO)

Copied from CLR via C# by Jeffrey Richter...

I often hear the question, “Should I design a base type or an interface?” The answer isn’t always clearcut.

Here are some guidelines that might help you:

¦¦ IS-A vs. CAN-DO relationship A type can inherit only one implementation. If the derived type can’t claim an IS-A relationship with the base type, don’t use a base type; use an interface. Interfaces imply a CAN-DO relationship. If the CAN-DO functionality appears to belong with various object types, use an interface. For example, a type can convert instances of itself to another type (IConvertible), a type can serialize an instance of itself (ISerializable), etc. Note that value types must be derived from System.ValueType, and therefore, they cannot be derived from an arbitrary base class. In this case, you must use a CAN-DO relationship and define an interface.

¦¦ Ease of use It’s generally easier for you as a developer to define a new type derived from a base type than to implement all of the methods of an interface. The base type can provide a lot of functionality, so the derived type probably needs only relatively small modifications to its behavior. If you supply an interface, the new type must implement all of the members.

¦¦ Consistent implementation No matter how well an interface contract is documented, it’s very unlikely that everyone will implement the contract 100 percent correctly. In fact, COM suffers from this very problem, which is why some COM objects work correctly only with Microsoft Word or with Windows Internet Explorer. By providing a base type with a good default implementation, you start off using a type that works and is well tested; you can then modify parts that need modification.

¦¦ Versioning If you add a method to the base type, the derived type inherits the new method, you start off using a type that works, and the user’s source code doesn’t even have to be recompiled. Adding a new member to an interface forces the inheritor of the interface to change its source code and recompile.

How to put two divs side by side

<div style="display: inline">
    <div style="width:80%; display: inline-block; float:left; margin-right: 10px;"></div>
    <div style="width: 19%; display: inline-block; border: 1px solid red"></div>
</div>

Where to place the 'assets' folder in Android Studio?

Click over main ? new -> directory ? and type as name "assets"

or... main -> new -> folder -> assets folder (see image)

enter image description here

Postgres: How to convert a json string to text?

Mr. Curious was curious about this as well. In addition to the #>> '{}' operator, in 9.6+ one can get the value of a jsonb string with the ->> operator:

select to_jsonb('Some "text"'::TEXT)->>0;
  ?column?
-------------
 Some "text"
(1 row)

If one has a json value, then the solution is to cast into jsonb first:

select to_json('Some "text"'::TEXT)::jsonb->>0;
  ?column?
-------------
 Some "text"
(1 row)

No process is on the other end of the pipe (SQL Server 2012)

Had this error too, the cause was simple, but not obvious: incorrect password. Not sure why I didn't get just "Login failed" from freshly installed SQL 2016 server.

Pass Multiple Parameters to jQuery ajax call

            data: JSON.stringify({ "objectnameOFcontroller": data, "Sel": $(th).val() }),

controller object name

Pandas merge two dataframes with different columns

I think in this case concat is what you want:

In [12]:

pd.concat([df,df1], axis=0, ignore_index=True)
Out[12]:
   attr_1  attr_2  attr_3  id  quantity
0       0       1     NaN   1        20
1       1       1     NaN   2        23
2       1       1     NaN   3        19
3       0       0     NaN   4        19
4       1     NaN       0   5         8
5       0     NaN       1   6        13
6       1     NaN       1   7        20
7       1     NaN       1   8        25

by passing axis=0 here you are stacking the df's on top of each other which I believe is what you want then producing NaN value where they are absent from their respective dfs.

Custom Cell Row Height setting in storyboard is not responding

One other thing you can do is to go to your Document Outline, select the table view that your prototype cell is nested. Then on the Size Inspector, change your table view Row Height to your desired value and uncheck the Automatic box.

How do I increment a DOS variable in a FOR /F loop?

I would like to add that in case in you create local variables within the loop, they need to be expanded using the bang(!) notation as well. Extending the example at https://stackoverflow.com/a/2919699 above, if we want to create counter-based output filenames

set TEXT_T="myfile.txt"

set /a c=1

setlocal ENABLEDELAYEDEXPANSION

FOR /F "tokens=1 usebackq" %%i in (%TEXT_T%) do (
    set /a c=c+1
    set OUTPUT_FILE_NAME=output_!c!.txt
    echo Output file is !OUTPUT_FILE_NAME!
    echo %%i, !c!
)

endlocal

How to display a json array in table format?

var data = [
    {
        id : "001",
        name : "apple",
        category : "fruit",
        color : "red"
    },
    {
        id : "002",
        name : "melon",
        category : "fruit",
        color : "green"
    },
    {
        id : "003",
        name : "banana",
        category : "fruit",
        color : "yellow"
    }
];

for(var i = 0, len = data.length; i < length; i++) {
    var temp = '<tr><td>' + data[i].id + '</td>';
    temp+= '<td>' + data[i].name+ '</td>';
    temp+= '<td>' + data[i].category + '</td>';
    temp+= '<td>' + data[i].color + '</td></tr>';
    $('table tbody').append(temp));
}

Calling Scalar-valued Functions in SQL

Can do the following

PRINT dbo.[FunctionName] ( [Parameter/Argument] )

E.g.:

PRINT dbo.StringSplit('77,54')

How to vertically center a "div" element for all browsers using CSS?

I find this one most useful.. it gives the most accurate 'H' layout and is very simple to understand.

The benefit in this markup is that you define your content size in a single place -> "PageContent".
The Colors of the page background and its horizontal margins are defined in their corresponding divs.

<div id="PageLayoutConfiguration" 
     style="display: table;
     position:absolute; top: 0px; right: 0px; bottom: 0px; left: 0px;
     width: 100%; height: 100%;">

        <div id="PageBackground" 
             style="display: table-cell; vertical-align: middle;
             background-color: purple;">

            <div id="PageHorizontalMargins"
                 style="width: 100%;
                 background-color: seashell;">

                <div id="PageContent" 
                     style="width: 1200px; height: 620px; margin: 0 auto;
                     background-color: grey;">

                     my content goes here...

                </div>
            </div>
        </div>
    </div>

And here with CSS separated:

<div id="PageLayoutConfiguration">
     <div id="PageBackground">
          <div id="PageHorizontalMargins">
               <div id="PageContent">
                     my content goes here...
               </div>
          </div>
     </div>
</div>

#PageLayoutConfiguration{
   display: table; width: 100%; height: 100%;
   position:absolute; top: 0px; right: 0px; bottom: 0px; left: 0px;
}

#PageBackground{
   display: table-cell; vertical-align: middle;
   background-color: purple;
}

#PageHorizontalMargins{
   style="width: 100%;
   background-color: seashell;
}
#PageContent{
   width: 1200px; height: 620px; margin: 0 auto;
   background-color: grey;
}

What good technology podcasts are out there?

Most of the podcasts I listened to are already discussed above.

  • .NET Rocks
  • HanselMinutes
  • RunAsRadio
  • Mondays (for when you are bored with development stuffs)
  • Herding Code
  • Arcast (used to)
  • AudibleAjax
  • OpenWeb

There are some bits from OOPSLA that were interesting as well (not long running podcasts, but it's nice to hear).

MVC4 Passing model from view to controller

I hope this complete example will help you.

This is the TaxiInfo class which holds information about a taxi ride:

namespace Taxi.Models
{
    public class TaxiInfo
    {
        public String Driver { get; set; }
        public Double Fare { get; set; }
        public Double Distance { get; set; }
        public String StartLocation { get; set; }
        public String EndLocation { get; set; }
    }
}

We also have a convenience model which holds a List of TaxiInfo(s):

namespace Taxi.Models
{
    public class TaxiInfoSet
    {
        public List<TaxiInfo> TaxiInfoList { get; set; }

        public TaxiInfoSet(params TaxiInfo[] TaxiInfos)
        {
            TaxiInfoList = new List<TaxiInfo>();

            foreach(var TaxiInfo in TaxiInfos)
            {
                TaxiInfoList.Add(TaxiInfo);
            }
        }
    }
}

Now in the home controller we have the default Index action which for this example makes two taxi drivers and adds them to the list contained in a TaxiInfo:

public ActionResult Index()
{
    var taxi1 = new TaxiInfo() { Fare = 20.2, Distance = 15, Driver = "Billy", StartLocation = "Perth", EndLocation = "Brisbane" };
    var taxi2 = new TaxiInfo() { Fare = 2339.2, Distance = 1500, Driver = "Smith", StartLocation = "Perth", EndLocation = "America" };

    return View(new TaxiInfoSet(taxi1,taxi2));
}

The code for the view is as follows:

@model Taxi.Models.TaxiInfoSet
@{
    ViewBag.Title = "Index";
}

<h2>Index</h2>

@foreach(var TaxiInfo in Model.TaxiInfoList){
    <form>
        <h1>Cost: [email protected]</h1>
        <h2>Distance: @(TaxiInfo.Distance) km</h2>
        <p>
            Our diver, @TaxiInfo.Driver will take you from @TaxiInfo.StartLocation to @TaxiInfo.EndLocation
        </p>
        @Html.ActionLink("Home","Booking",TaxiInfo)
    </form>
}

The ActionLink is responsible for the re-directing to the booking action of the Home controller (and passing in the appropriate TaxiInfo object) which is defiend as follows:

    public ActionResult Booking(TaxiInfo Taxi)
    {
        return View(Taxi);
    }

This returns a the following view:

@model Taxi.Models.TaxiInfo

@{
    ViewBag.Title = "Booking";
}

<h2>Booking For</h2>
<h1>@Model.Driver, going from @Model.StartLocation to @Model.EndLocation (a total of @Model.Distance km) for [email protected]</h1>

A visual tour:

The Index view

The Booking view

Count character occurrences in a string in C++

#include <algorithm>

std::string s = "a_b_c";
size_t n = std::count(s.begin(), s.end(), '_');

Why does this SQL code give error 1066 (Not unique table/alias: 'user')?

Your error is because you have:

     JOIN user ON article.author_id = user.id
LEFT JOIN user ON article.modified_by = user.id

You have two instances of the same table, but the database can't determine which is which. To fix this, you need to use table aliases:

     JOIN USER u ON article.author_id = u.id
LEFT JOIN USER u2 ON article.modified_by = u2.id

It's good habit to always alias your tables, unless you like writing the full table name all the time when you don't have situations like these.

The next issues to address will be:

SELECT article.* , section.title, category.title, user.name, user.name

1) Never use SELECT * - always spell out the columns you want, even if it is the entire table. Read this SO Question to understand why.

2) You'll get ambiguous column errors relating to the user.name columns because again, the database can't tell which table instance to pull data from. Using table aliases fixes the issue:

SELECT article.* , section.title, category.title, u.name, u2.name

Find the nth occurrence of substring in a string

This is the answer you really want:

def Find(String,ToFind,Occurence = 1):
index = 0 
count = 0
while index <= len(String):
    try:
        if String[index:index + len(ToFind)] == ToFind:
            count += 1
        if count == Occurence:
               return index
               break
        index += 1
    except IndexError:
        return False
        break
return False

How do I get a consistent byte representation of strings in C# without manually specifying an encoding?

byte[] strToByteArray(string str)
{
    System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding();
    return enc.GetBytes(str);
}

Keyboard shortcut to paste clipboard content into command prompt window (Win XP)

I personally use a little AutoHotkey script to remap certain keyboard functions, for the console window (CMD) I use:

; Redefine only when the active window is a console window 
#IfWinActive ahk_class ConsoleWindowClass

; Close Command Window with Ctrl+w
$^w::
WinGetTitle sTitle
If (InStr(sTitle, "-")=0) { 
    Send EXIT{Enter}
} else {
    Send ^w
}

return 


; Ctrl+up / Down to scroll command window back and forward
^Up::
Send {WheelUp}
return

^Down::
Send {WheelDown}
return


; Paste in command window
^V::
; Spanish menu (Editar->Pegar, I suppose English version is the same, Edit->Paste)
Send !{Space}ep
return

#IfWinActive 

Create web service proxy in Visual Studio from a WSDL file

save the file on your disk and then use the following as URL:

file://your_path/your_file.wsdl

javax.persistence.NoResultException: No entity found for query

When using java 8, you may take advantage of stream API and simplify code to

return (YourEntityClass) entityManager.createQuery()
....
.getResultList()
.stream().findFirst();

That will give you java.util.Optional

If you prefer null instead, all you need is

 ...
.getResultList()
.stream().findFirst().orElse(null);

navigator.geolocation.getCurrentPosition sometimes works sometimes doesn't

The second parameter passed to Geolocation.getCurrentPosition() is the function you want to handle any geolocation errors. The error handler function itself receives a PositionError object with details about why the geolocation attempt failed. I recommend outputting the error to the console if you have any issues:

var positionOptions = { timeout: 10000 };
navigator.geolocation.getCurrentPosition(updateLocation, errorHandler, positionOptions);
function updateLocation(position) {
  // The geolocation succeeded, and the position is available
}
function errorHandler(positionError) {
  if (window.console) {
    console.log(positionError);
  }
}

Doing this in my code revealed the message "Network location provider at 'https://www.googleapis.com/' : Returned error code 400". Turns out Google Chrome uses the Google APIs to get a location on devices that don't have GPS built in (for example, most desktop computers). Google returns an approximate latitude/longitude based on the user's IP address. However, in developer builds of Chrome (such as Chromium on Ubuntu) there is no API access key included in the browser build. This causes the API request to fail silently. See Chromium Issue 179686: Geolocation giving 403 error for details.

Display XML content in HTML page

If you treat the content as text, not HTML, then DOM operations should cause the data to be properly encoded. Here's how you'd do it in jQuery:

$('#container').text(xmlString);

Here's how you'd do it with standard DOM methods:

document.getElementById('container')
        .appendChild(document.createTextNode(xmlString));

If you're placing the XML inside of HTML through server-side scripting, there are bound to be encoding functions to allow you to do that (if you add what your server-side technology is, we can give you specific examples of how you'd do it).

How to write :hover using inline style?

Not gonna happen with CSS only

Inline javascript

<a href='index.html' 
    onmouseover='this.style.textDecoration="none"' 
    onmouseout='this.style.textDecoration="underline"'>
    Click Me
</a>

In a working draft of the CSS2 spec it was declared that you could use pseudo-classes inline like this:

<a href="http://www.w3.org/Style/CSS"
   style="{color: blue; background: white}  /* a+=0 b+=0 c+=0 */
      :visited {color: green}           /* a+=0 b+=1 c+=0 */
      :hover {background: yellow}       /* a+=0 b+=1 c+=0 */
      :visited:hover {color: purple}    /* a+=0 b+=2 c+=0 */
     ">
</a>

but it was never implemented in the release of the spec as far as I know.

http://www.w3.org/TR/2002/WD-css-style-attr-20020515#pseudo-rules

Angular JS POST request not sending JSON data

$http({
    url: '/api/user',
    method: "POST",
    data: angular.toJson(yourData)
}).success(function (data, status, headers, config) {
    $scope.users = data.users;
}).error(function (data, status, headers, config) {
    $scope.status = status + ' ' + headers;
});

PHP + curl, HTTP POST sample code?

Procedural

// set post fields
$post = [
    'username' => 'user1',
    'password' => 'passuser1',
    'gender'   => 1,
];

$ch = curl_init('http://www.example.com');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $post);

// execute!
$response = curl_exec($ch);

// close the connection, release resources used
curl_close($ch);

// do anything you want with your response
var_dump($response);

Object oriented

<?php

// mutatis mutandis
namespace MyApp\Http;

class CurlPost
{
    private $url;
    private $options;
           
    /**
     * @param string $url     Request URL
     * @param array  $options cURL options
     */
    public function __construct($url, array $options = [])
    {
        $this->url = $url;
        $this->options = $options;
    }

    /**
     * Get the response
     * @return string
     * @throws \RuntimeException On cURL error
     */
    public function __invoke(array $post)
    {
        $ch = \curl_init($this->url);
        
        foreach ($this->options as $key => $val) {
            \curl_setopt($ch, $key, $val);
        }

        \curl_setopt($ch, \CURLOPT_RETURNTRANSFER, true);
        \curl_setopt($ch, \CURLOPT_POSTFIELDS, $post);

        $response = \curl_exec($ch);
        $error    = \curl_error($ch);
        $errno    = \curl_errno($ch);
        
        if (\is_resource($ch)) {
            \curl_close($ch);
        }

        if (0 !== $errno) {
            throw new \RuntimeException($error, $errno);
        }
        
        return $response;
    }
}

Usage

// create curl object
$curl = new \MyApp\Http\CurlPost('http://www.example.com');

try {
    // execute the request
    echo $curl([
        'username' => 'user1',
        'password' => 'passuser1',
        'gender'   => 1,
    ]);
} catch (\RuntimeException $ex) {
    // catch errors
    die(sprintf('Http error %s with code %d', $ex->getMessage(), $ex->getCode()));
}

Side note here: it would be best to create some kind of interface called AdapterInterface for example with getResponse() method and let the class above implement it. Then you can always swap this implementation with another adapter of your like, without any side effects to your application.

Using HTTPS / encrypting traffic

Usually there's a problem with cURL in PHP under the Windows operating system. While trying to connect to a https protected endpoint, you will get an error telling you that certificate verify failed.

What most people do here is to tell the cURL library to simply ignore certificate errors and continue (curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);). As this will make your code work, you introduce huge security hole and enable malicious users to perform various attacks on your app like Man In The Middle attack or such.

Never, ever do that. Instead, you simply need to modify your php.ini and tell PHP where your CA Certificate file is to let it verify certificates correctly:

; modify the absolute path to the cacert.pem file
curl.cainfo=c:\php\cacert.pem

The latest cacert.pem can be downloaded from the Internet or extracted from your favorite browser. When changing any php.ini related settings remember to restart your webserver.

Redirecting to a page after submitting form in HTML

What you could do is, a validation of the values, for example:

if the value of the input of fullanme is greater than some value length and if the value of the input of address is greater than some value length then redirect to a new page, otherwise shows an error for the input.

_x000D_
_x000D_
// We access to the inputs by their id's
let fullname = document.getElementById("fullname");
let address = document.getElementById("address");

// Error messages
let errorElement = document.getElementById("name_error");
let errorElementAddress = document.getElementById("address_error");

// Form
let contactForm = document.getElementById("form");

// Event listener
contactForm.addEventListener("submit", function (e) {
  let messageName = [];
  let messageAddress = [];
  
    if (fullname.value === "" || fullname.value === null) {
    messageName.push("* This field is required");
  }

  if (address.value === "" || address.value === null) {
    messageAddress.push("* This field is required");
  }

  // Statement to shows the errors
  if (messageName.length || messageAddress.length > 0) {
    e.preventDefault();
    errorElement.innerText = messageName;
    errorElementAddress.innerText = messageAddress;
  }
  
   // if the values length is filled and it's greater than 2 then redirect to this page
    if (
    (fullname.value.length > 2,
    address.value.length > 2)
  ) {
    e.preventDefault();
    window.location.assign("https://www.google.com");
  }

});
_x000D_
.error {
  color: #000;
}

.input-container {
  display: flex;
  flex-direction: column;
  margin: 1rem auto;
}
_x000D_
<html>
  <body>
    <form id="form" method="POST">
    <div class="input-container">
    <label>Full name:</label>
      <input type="text" id="fullname" name="fullname">
      <div class="error" id="name_error"></div>
      </div>
      
      <div class="input-container">
      <label>Address:</label>
      <input type="text" id="address" name="address">
      <div class="error" id="address_error"></div>
      </div>
      <button type="submit" id="submit_button" value="Submit request" >Submit</button>
    </form>
  </body>
</html>
_x000D_
_x000D_
_x000D_

How to bind 'touchstart' and 'click' events but not respond to both?

Instead of the timeout you could use a counter:

var count = 0;
$thing.bind('touchstart click', function(){
  count++;
  if (count %2 == 0) { //count 2% gives the remaining counts when devided by 2
    // do something
  }

  return false
});

How to use double or single brackets, parentheses, curly braces

The difference between test, [ and [[ is explained in great details in the BashFAQ.

To cut a long story short: test implements the old, portable syntax of the command. In almost all shells (the oldest Bourne shells are the exception), [ is a synonym for test (but requires a final argument of ]). Although all modern shells have built-in implementations of [, there usually still is an external executable of that name, e.g. /bin/[.

[[ is a new improved version of it, which is a keyword, not a program. This has beneficial effects on the ease of use, as shown below. [[ is understood by KornShell and BASH (e.g. 2.03), but not by the older POSIX or BourneShell.

And the conclusion:

When should the new test command [[ be used, and when the old one [? If portability to the BourneShell is a concern, the old syntax should be used. If on the other hand the script requires BASH or KornShell, the new syntax is much more flexible.

How to create an 2D ArrayList in java?

I want to create a 2D array that each cell is an ArrayList!

If you want to create a 2D array of ArrayList.Then you can do this :

ArrayList[][] table = new ArrayList[10][10];
table[0][0] = new ArrayList(); // add another ArrayList object to [0,0]
table[0][0].add(); // add object to that ArrayList

How to check if the key pressed was an arrow key in Java KeyListener?

public void keyPressed(KeyEvent e) {
    if (e.getKeyCode() == KeyEvent.VK_RIGHT ) {
            //Right arrow key code
    } else if (e.getKeyCode() == KeyEvent.VK_LEFT ) {
            //Left arrow key code
    } else if (e.getKeyCode() == KeyEvent.VK_UP ) {
            //Up arrow key code
    } else if (e.getKeyCode() == KeyEvent.VK_DOWN ) {
            //Down arrow key code
    }

    repaint();
}

The KeyEvent codes are all a part of the API: http://docs.oracle.com/javase/7/docs/api/java/awt/event/KeyEvent.html

What is a stack trace, and how can I use it to debug my application errors?

In simple terms, a stack trace is a list of the method calls that the application was in the middle of when an Exception was thrown.

Simple Example

With the example given in the question, we can determine exactly where the exception was thrown in the application. Let's have a look at the stack trace:

Exception in thread "main" java.lang.NullPointerException
        at com.example.myproject.Book.getTitle(Book.java:16)
        at com.example.myproject.Author.getBookTitles(Author.java:25)
        at com.example.myproject.Bootstrap.main(Bootstrap.java:14)

This is a very simple stack trace. If we start at the beginning of the list of "at ...", we can tell where our error happened. What we're looking for is the topmost method call that is part of our application. In this case, it's:

at com.example.myproject.Book.getTitle(Book.java:16)

To debug this, we can open up Book.java and look at line 16, which is:

15   public String getTitle() {
16      System.out.println(title.toString());
17      return title;
18   }

This would indicate that something (probably title) is null in the above code.

Example with a chain of exceptions

Sometimes applications will catch an Exception and re-throw it as the cause of another Exception. This typically looks like:

34   public void getBookIds(int id) {
35      try {
36         book.getId(id);    // this method it throws a NullPointerException on line 22
37      } catch (NullPointerException e) {
38         throw new IllegalStateException("A book has a null property", e)
39      }
40   }

This might give you a stack trace that looks like:

Exception in thread "main" java.lang.IllegalStateException: A book has a null property
        at com.example.myproject.Author.getBookIds(Author.java:38)
        at com.example.myproject.Bootstrap.main(Bootstrap.java:14)
Caused by: java.lang.NullPointerException
        at com.example.myproject.Book.getId(Book.java:22)
        at com.example.myproject.Author.getBookIds(Author.java:36)
        ... 1 more

What's different about this one is the "Caused by". Sometimes exceptions will have multiple "Caused by" sections. For these, you typically want to find the "root cause", which will be one of the lowest "Caused by" sections in the stack trace. In our case, it's:

Caused by: java.lang.NullPointerException <-- root cause
        at com.example.myproject.Book.getId(Book.java:22) <-- important line

Again, with this exception we'd want to look at line 22 of Book.java to see what might cause the NullPointerException here.

More daunting example with library code

Usually stack traces are much more complex than the two examples above. Here's an example (it's a long one, but demonstrates several levels of chained exceptions):

javax.servlet.ServletException: Something bad happened
    at com.example.myproject.OpenSessionInViewFilter.doFilter(OpenSessionInViewFilter.java:60)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.example.myproject.ExceptionHandlerFilter.doFilter(ExceptionHandlerFilter.java:28)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at com.example.myproject.OutputBufferFilter.doFilter(OutputBufferFilter.java:33)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
    at org.mortbay.jetty.Server.handle(Server.java:326)
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
    at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:943)
    at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
    at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
    at org.mortbay.jetty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
    at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)
Caused by: com.example.myproject.MyProjectServletException
    at com.example.myproject.MyServlet.doPost(MyServlet.java:169)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
    at com.example.myproject.OpenSessionInViewFilter.doFilter(OpenSessionInViewFilter.java:30)
    ... 27 more
Caused by: org.hibernate.exception.ConstraintViolationException: could not insert: [com.example.myproject.MyEntity]
    at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:96)
    at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
    at org.hibernate.id.insert.AbstractSelectingDelegate.performInsert(AbstractSelectingDelegate.java:64)
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2329)
    at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2822)
    at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:71)
    at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:268)
    at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:321)
    at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:204)
    at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:130)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:210)
    at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:56)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:195)
    at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:50)
    at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:93)
    at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:705)
    at org.hibernate.impl.SessionImpl.save(SessionImpl.java:693)
    at org.hibernate.impl.SessionImpl.save(SessionImpl.java:689)
    at sun.reflect.GeneratedMethodAccessor5.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.hibernate.context.ThreadLocalSessionContext$TransactionProtectionWrapper.invoke(ThreadLocalSessionContext.java:344)
    at $Proxy19.save(Unknown Source)
    at com.example.myproject.MyEntityService.save(MyEntityService.java:59) <-- relevant call (see notes below)
    at com.example.myproject.MyServlet.doPost(MyServlet.java:164)
    ... 32 more
Caused by: java.sql.SQLException: Violation of unique constraint MY_ENTITY_UK_1: duplicate value(s) for column(s) MY_COLUMN in statement [...]
    at org.hsqldb.jdbc.Util.throwError(Unknown Source)
    at org.hsqldb.jdbc.jdbcPreparedStatement.executeUpdate(Unknown Source)
    at com.mchange.v2.c3p0.impl.NewProxyPreparedStatement.executeUpdate(NewProxyPreparedStatement.java:105)
    at org.hibernate.id.insert.AbstractSelectingDelegate.performInsert(AbstractSelectingDelegate.java:57)
    ... 54 more

In this example, there's a lot more. What we're mostly concerned about is looking for methods that are from our code, which would be anything in the com.example.myproject package. From the second example (above), we'd first want to look down for the root cause, which is:

Caused by: java.sql.SQLException

However, all the method calls under that are library code. So we'll move up to the "Caused by" above it, and look for the first method call originating from our code, which is:

at com.example.myproject.MyEntityService.save(MyEntityService.java:59)

Like in previous examples, we should look at MyEntityService.java on line 59, because that's where this error originated (this one's a bit obvious what went wrong, since the SQLException states the error, but the debugging procedure is what we're after).

Cleaning up old remote git branches

This command will "dry run" delete all remote (origin) merged branches, apart from master. You can change that, or, add additional branches after master: grep -v for-example-your-branch-here |

git branch -r --merged | 
  grep origin | 
  grep -v '>' | 
  grep -v master | 
  xargs -L1 | 
  awk '{sub(/origin\//,"");print}'| 
  xargs git push origin --delete --dry-run

If it looks good, remove the --dry-run. Additionally, you may like to test this on a fork first.

How to attach source or JavaDoc in eclipse for any jar file e.g. JavaFX?

You could specify the online Javadoc location for a particular JAR in Eclipse. This saved my day when I wasn't able to find any downloadable Javadocs for Kafka.

  1. In the Package Explorer, right click on the intended JAR (under the project's Referenced Libraries or Maven Dependences or anything as such) and click on Properties.
  2. Click on Javadoc Location.
  3. In the Javadoc location path field under Javadoc URL, enter the URL of the online Javadocs, which most likely ends with /<version>/javadoc/. For example, Kafka 2.3.0's Javadocs are located at http://www.apache.org/dist/kafka/2.3.0/javadoc/ (you might want to change https to http in your URL, as it raised an invalid location warning after clicking on Validate... for me).

Retrieving a Foreign Key value with django-rest-framework serializers

This solution is better because of no need to define the source model. But the name of the serializer field should be the same as the foreign key field name

class ItemSerializer(serializers.ModelSerializer):
    category = serializers.SlugRelatedField(read_only=True, slug_field='title')

    class Meta:
        model = Item
        fields = ('id', 'name', 'category')

Angular JS break ForEach

I realise this is old, but an array filter may do what you need:

var arr = [0, 1, 2].filter(function (count) {
    return count < 1;
});

You can then run arr.forEach and other array functions.

I realise that if you intend to cut down on loop operations altogether, this will probably not do what you want. For that you best use while.

Extracting the top 5 maximum values in excel

Put the data into a Pivot Table and do a top n filter on it

Excel Demo

android adb turn on wifi via adb

I was in the same situation on a Samsung Mini II. I got around it eventually by holding down the power button until the "power off" menu appeared. From this menu it was possible to enable the network data connection.

Then signing in to my google account using @googlemail.com (rather than @gmail.com) seemed to do the trick. Though the change of address may just have given the phone time to warm up the 3g connection rather than making any real difference.

Error:Execution failed for task ':app:compileDebugKotlin'. > Compilation error. See log for more details

In my case, I attempted to upgrade play_servicesand firebase versions to 15.0. Going back to 11.4.2 fixed my issue...

What are the nuances of scope prototypal / prototypical inheritance in AngularJS?

I would like to add an example of prototypical inheritance with javascript to @Scott Driscoll answer. We'll be using classical inheritance pattern with Object.create() which is a part of EcmaScript 5 specification.

First we create "Parent" object function

function Parent(){

}

Then add a prototype to "Parent" object function

 Parent.prototype = {
 primitive : 1,
 object : {
    one : 1
   }
}

Create "Child" object function

function Child(){

}

Assign child prototype (Make child prototype inherit from parent prototype)

Child.prototype = Object.create(Parent.prototype);

Assign proper "Child" prototype constructor

Child.prototype.constructor = Child;

Add method "changeProps" to a child prototype, which will rewrite "primitive" property value in Child object and change "object.one" value both in Child and Parent objects

Child.prototype.changeProps = function(){
    this.primitive = 2;
    this.object.one = 2;
};

Initiate Parent (dad) and Child (son) objects.

var dad = new Parent();
var son = new Child();

Call Child (son) changeProps method

son.changeProps();

Check the results.

Parent primitive property did not change

console.log(dad.primitive); /* 1 */

Child primitive property changed (rewritten)

console.log(son.primitive); /* 2 */

Parent and Child object.one properties changed

console.log(dad.object.one); /* 2 */
console.log(son.object.one); /* 2 */

Working example here http://jsbin.com/xexurukiso/1/edit/

More info on Object.create here https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/create

One line if statement not working

From what I know

3 one-liners

  1. a = 10 if <condition>

example:

a = 10 if true # a = 10
b = 10 if false # b = nil
  1. a = 10 unless <condition>

example:

a = 10 unless false # a = 10
b = 10 unless true # b = nil
  1. a = <condition> ? <a> : <b>

example:

a = true ? 10 : 100 # a = 10
a = false ? 10 : 100 # a = 100

I hope it helps.

What is the purpose of the HTML "no-js" class?

When Modernizr runs, it removes the "no-js" class and replaces it with "js". This is a way to apply different CSS rules depending on whether or not Javascript support is enabled.

See Modernizer's source code.

How to remove tab indent from several lines in IDLE?

Depends on your editor.

Have you tried Shift+Tab?

How to create a jQuery plugin with methods?

I think this might help you...

_x000D_
_x000D_
(function ( $ ) {_x000D_
  _x000D_
    $.fn.highlight = function( options ) {_x000D_
  _x000D_
        // This is the easiest way to have default options._x000D_
        var settings = $.extend({_x000D_
            // These are the defaults._x000D_
            color: "#000",_x000D_
            backgroundColor: "yellow"_x000D_
        }, options );_x000D_
  _x000D_
        // Highlight the collection based on the settings variable._x000D_
        return this.css({_x000D_
            color: settings.color,_x000D_
            backgroundColor: settings.backgroundColor_x000D_
        });_x000D_
  _x000D_
    };_x000D_
  _x000D_
}( jQuery ));
_x000D_
_x000D_
_x000D_

In the above example i had created a simple jquery highlight plugin.I had shared an article in which i had discussed about How to Create Your Own jQuery Plugin from Basic to Advance. I think you should check it out... http://mycodingtricks.com/jquery/how-to-create-your-own-jquery-plugin/

Get url without querystring

this.Request.RawUrl.Substring(0, this.Request.RawUrl.IndexOf('?'))

Apply function to each element of a list

Or, alternatively, you can take a list comprehension approach:

>>> mylis = ['this is test', 'another test']
>>> [item.upper() for item in mylis]
['THIS IS TEST', 'ANOTHER TEST']

Gradle project refresh failed after Android Studio update

File -> Invalidate Caches / Restart -> Invalidate and Restart worked for me.

Insert an element at a specific index in a list and return the updated list

The cleanest approach is to copy the list and then insert the object into the copy. On Python 3 this can be done via list.copy:

new = old.copy()
new.insert(index, value)

On Python 2 copying the list can be achieved via new = old[:] (this also works on Python 3).

In terms of performance there is no difference to other proposed methods:

$ python --version
Python 3.8.1
$ python -m timeit -s "a = list(range(1000))" "b = a.copy(); b.insert(500, 3)"
100000 loops, best of 5: 2.84 µsec per loop
$ python -m timeit -s "a = list(range(1000))" "b = a.copy(); b[500:500] = (3,)"
100000 loops, best of 5: 2.76 µsec per loop

Finding the indices of matching elements in list in Python

>>> average =  [1,3,2,1,1,0,24,23,7,2,727,2,7,68,7,83,2]
>>> matches = [i for i in range(0,len(average)) if average[i]<2 or average[i]>4]
>>> matches
[0, 3, 4, 5, 6, 7, 8, 10, 12, 13, 14, 15]

Full examples of using pySerial package

Blog post Serial RS232 connections in Python

import time
import serial

# configure the serial connections (the parameters differs on the device you are connecting to)
ser = serial.Serial(
    port='/dev/ttyUSB1',
    baudrate=9600,
    parity=serial.PARITY_ODD,
    stopbits=serial.STOPBITS_TWO,
    bytesize=serial.SEVENBITS
)

ser.isOpen()

print 'Enter your commands below.\r\nInsert "exit" to leave the application.'

input=1
while 1 :
    # get keyboard input
    input = raw_input(">> ")
        # Python 3 users
        # input = input(">> ")
    if input == 'exit':
        ser.close()
        exit()
    else:
        # send the character to the device
        # (note that I happend a \r\n carriage return and line feed to the characters - this is requested by my device)
        ser.write(input + '\r\n')
        out = ''
        # let's wait one second before reading output (let's give device time to answer)
        time.sleep(1)
        while ser.inWaiting() > 0:
            out += ser.read(1)

        if out != '':
            print ">>" + out

When running WebDriver with Chrome browser, getting message, "Only local connections are allowed" even though browser launches properly

Very often this error appears if you use incompatible versions of Selenium and ChromeDriver.

Selenium 3.0.1 for Maven project:

    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>3.0.1</version>
    </dependency>

ChromeDriver 2.27: https://sites.google.com/a/chromium.org/chromedriver/downloads

Android Stop Emulator from Command Line

To stop all running emulators we use this command:

adb devices | grep emulator | cut -f1 | while read line; do adb -s $line emu kill; done

receiving error: 'Error: SSL Error: SELF_SIGNED_CERT_IN_CHAIN' while using npm

The repository no longer supports self-signed certificates. You need to upgrade npm.

// Disable the certificate temporarily in order to do the upgrade
npm config set ca ""

// Upgrade npm. -g (global) means you need root permissions; be root 
// or prepend `sudo`
sudo npm install npm -g

// Undo the previous config change
npm config delete ca

// For Ubuntu/Debian-sid/Mint, node package is renamed to nodejs which 
// npm cannot find. Fix this:
sudo ln -s /usr/bin/nodejs /usr/bin/node

You need to open a new terminal session in order to use the updated npm.

Source: This was originally an edit on jnylen's answer. Although the guidelines say "We welcome all constructive edits, but please make them substantial," the edit was rejected due to "This edit changes too much in the original post; the original meaning or intent of the post would be lost." I guess the community prefers a separate answer.

Getting only 1 decimal place

Are you trying to represent it with only one digit:

print("{:.1f}".format(number)) # Python3
print "%.1f" % number          # Python2

or actually round off the other decimal places?

round(number,1)

or even round strictly down?

math.floor(number*10)/10

ASP.NET strange compilation error

I just ran into this on .NET 4.6.1 and it ultimately had a simple solution - I removed (actually commented out) the section in the web.config and the web forms application came back to life. See what-exactly-does-system-codedom-compilers-do-in-web-config-in-mvc-5 for more info.

It worked for me.

urlencode vs rawurlencode?

I believe urlencode is for query parameters, whereas the rawurlencode is for the path segments. This is mainly due to %20 for path segments vs + for query parameters. See this answer which talks about the spaces: When to encode space to plus (+) or %20?

However %20 now works in query parameters as well, which is why rawurlencode is always safer. However the plus sign tends to be used where user experience of editing and readability of query parameters matter.

Note that this means rawurldecode does not decode + into spaces (http://au2.php.net/manual/en/function.rawurldecode.php). This is why the $_GET is always automatically passed through urldecode, which means that + and %20 are both decoded into spaces.

If you want the encoding and decoding to be consistent between inputs and outputs and you have selected to always use + and not %20 for query parameters, then urlencode is fine for query parameters (key and value).

The conclusion is:

Path Segments - always use rawurlencode/rawurldecode

Query Parameters - for decoding always use urldecode (done automatically), for encoding, both rawurlencode or urlencode is fine, just choose one to be consistent, especially when comparing URLs.

How do I escape reserved words used as column names? MySQL/Create Table

You should use back tick character (`) eg:

create table if not exists misc_info (
id INTEGER PRIMARY KEY AUTO_INCREMENT NOT NULL,
`key` TEXT UNIQUE NOT NULL,
value TEXT NOT NULL)ENGINE=INNODB;

What is Cache-Control: private?

Cache-Control: private

Indicates that all or part of the response message is intended for a single user and MUST NOT be cached by a shared cache, such as a proxy server.

From RFC2616 section 14.9.1

How to remove item from array by value?

You can do it with these two ways:

const arr = ['1', '2', '3', '4'] // we wanna delete number "3"
  1. The first way:

    arr.indexOf('3') !== -1 && arr.splice(arr.indexOf('3'), 1)
    
  2. The second way (ES6) specially without mutate:

    const newArr = arr.filter(e => e !== '3')
    

Float and double datatype in Java

Floating-point numbers, also known as real numbers, are used when evaluating expressions that require fractional precision. For example, calculations such as square root, or transcendentals such as sine and cosine, result in a value whose precision requires a floating-point type. Java implements the standard (IEEE–754) set of floatingpoint types and operators. There are two kinds of floating-point types, float and double, which represent single- and double-precision numbers, respectively. Their width and ranges are shown here:


   Name     Width in Bits   Range 
    double  64              1 .7e–308 to 1.7e+308
    float   32              3 .4e–038 to 3.4e+038


float

The type float specifies a single-precision value that uses 32 bits of storage. Single precision is faster on some processors and takes half as much space as double precision, but will become imprecise when the values are either very large or very small. Variables of type float are useful when you need a fractional component, but don't require a large degree of precision.

Here are some example float variable declarations:

float hightemp, lowtemp;


double

Double precision, as denoted by the double keyword, uses 64 bits to store a value. Double precision is actually faster than single precision on some modern processors that have been optimized for high-speed mathematical calculations. All transcendental math functions, such as sin( ), cos( ), and sqrt( ), return double values. When you need to maintain accuracy over many iterative calculations, or are manipulating large-valued numbers, double is the best choice.

NVIDIA-SMI has failed because it couldn't communicate with the NVIDIA driver

My system version: ubuntu 20.04 LTS.

  • I solved this by generate a new MOK and enroll it into shim.

  • Without disable of Secure Boot, although it also really works for me.

  • Simply execute this command and follow what it suggests:

    sudo update-secureboot-policy --enroll-key
    

According to ubuntu's wiki: How can I do non-automated signing of drivers

What is an Android PendingIntent?

A Pending Intent specifies an action to take in the future. It lets you pass a future Intent to another application and allow that application to execute that Intent as if it had the same permissions as your application, whether or not your application is still around when the Intent is eventually invoked.

It is a token that you give to a foreign application which allows the foreign application to use your application’s permissions to execute a predefined piece of code.

If you give the foreign application an Intent, and that application sends/broadcasts the Intent you gave, they will execute the Intent with their own permissions. But if you instead give the foreign application a Pending Intent you created using your own permission, that application will execute the contained Intent using your application’s permission.

To perform a broadcast via a pending intent so get a PendingIntent via PendingIntent.getBroadcast(). To perform an activity via an pending intent you receive the activity via PendingIntent.getActivity().

It is an Intent action that you want to perform, but at a later time. Think of it a putting an Intent on ice. The reason it’s needed is because an Intent must be created and launched from a valid Context in your application, but there are certain cases where one is not available at the time you want to run the action because you are technically outside the application’s context (the two common examples are launching an Activity from a Notification or a BroadcastReceiver.

By creating a PendingIntent you want to use to launch, say, an Activity while you have the Context to do so (from inside another Activity or Service) you can pass that object around to something external in order for it to launch part of your application on your behalf.

A PendingIntent provides a means for applications to work, even after their process exits. Its important to note that even after the application that created the PendingIntent has been killed, that Intent can still run. A description of an Intent and target action to perform with it. Instances of this class are created with getActivity(Context, int, Intent, int), getBroadcast(Context, int, Intent, int), getService (Context, int, Intent, int); the returned object can be handed to other applications so that they can perform the action you described on your behalf at a later time.

By giving a PendingIntent to another application, you are granting it the right to perform the operation you have specified as if the other application was yourself (with the same permissions and identity). As such, you should be careful about how you build the PendingIntent: often, for example, the base Intent you supply will have the component name explicitly set to one of your own components, to ensure it is ultimately sent there and nowhere else.

A PendingIntent itself is simply a reference to a token maintained by the system describing the original data used to retrieve it. This means that, even if its owning application’s process is killed, the PendingIntent itself will remain usable from other processes that have been given it. If the creating application later re-retrieves the same kind of PendingIntent (same operation, same Intent action, data, categories, and components, and same flags), it will receive a PendingIntent representing the same token if that is still valid, and can thus call cancel() to remove it.

Full path from file input using jQuery

You can't: It's a security feature in all modern browsers.

For IE8, it's off by default, but can be reactivated using a security setting:

When a file is selected by using the input type=file object, the value of the value property depends on the value of the "Include local directory path when uploading files to a server" security setting for the security zone used to display the Web page containing the input object.

The fully qualified filename of the selected file is returned only when this setting is enabled. When the setting is disabled, Internet Explorer 8 replaces the local drive and directory path with the string C:\fakepath\ in order to prevent inappropriate information disclosure.

In all other current mainstream browsers I know of, it is also turned off. The file name is the best you can get.

More detailed info and good links in this question. It refers to getting the value server-side, but the issue is the same in JavaScript before the form's submission.

Using Case/Switch and GetType to determine the object

This won't directly solve your problem as you want to switch on your own user-defined types, but for the benefit of others who only want to switch on built-in types, you can use the TypeCode enumeration:

switch (Type.GetTypeCode(node.GetType()))
{
    case TypeCode.Decimal:
        // Handle Decimal
        break;

    case TypeCode.Int32:
        // Handle Int32
        break;
     ...
}

How do I convert an object to an array?

You can quickly convert deeply nested objects to associative arrays by relying on the behavior of the JSON encode/decode functions:

$array = json_decode(json_encode($response->response->docs), true);

What are XAND and XOR

XOR (not neither and not both) B'0110' is the inverse (dual) of IFF (if and only if) B'1001'.

Access Control Request Headers, is added to header in AJAX request with jQuery

Try to use the rack-cors gem. And add the header field in your Ajax call.

Accessing AppDelegate from framework?

If you're creating a framework the whole idea is to make it portable. Tying a framework to the app delegate defeats the purpose of building a framework. What is it you need the app delegate for?

Sending emails in Node.js?

campaign is a comprehensive solution for sending emails in Node, and it comes with a very simple API.

You instance it like this.

var client = require('campaign')({
  from: '[email protected]'
});

To send emails, you can use Mandrill, which is free and awesome. Just set your API key, like this:

process.env.MANDRILL_APIKEY = '<your api key>';

(if you want to send emails using another provider, check the docs)

Then, when you want to send an email, you can do it like this:

client.sendString('<p>{{something}}</p>', {
  to: ['[email protected]', '[email protected]'],
  subject: 'Some Subject',
  preview': 'The first line',
  something: 'this is what replaces that thing in the template'
}, done);

The GitHub repo has pretty extensive documentation.

How do I remove all non alphanumeric characters from a string except dash?

The regex is [^\w\s\-]*:

\s is better to use instead of space (), because there might be a tab in the text.

Remove privileges from MySQL database

As a side note, the reason revoke usage on *.* from 'phpmyadmin'@'localhost'; does not work is quite simple : There is no grant called USAGE.

The actual named grants are in the MySQL Documentation

The grant USAGE is a logical grant. How? 'phpmyadmin'@'localhost' has an entry in mysql.user where user='phpmyadmin' and host='localhost'. Any row in mysql.user semantically means USAGE. Running DROP USER 'phpmyadmin'@'localhost'; should work just fine. Under the hood, it's really doing this:

DELETE FROM mysql.user WHERE user='phpmyadmin' and host='localhost';
DELETE FROM mysql.db   WHERE user='phpmyadmin' and host='localhost';
FLUSH PRIVILEGES;

Therefore, the removal of a row from mysql.user constitutes running REVOKE USAGE, even though REVOKE USAGE cannot literally be executed.

StringBuilder vs String concatenation in toString() in Java

In Java 9 the version 1 should be faster because it is converted to invokedynamic call. More details can be found in JEP-280:

The idea is to replace the entire StringBuilder append dance with a simple invokedynamic call to java.lang.invoke.StringConcatFactory, that will accept the values in the need of concatenation.

Getting a list of values from a list of dicts

Assuming every dict has a value key, you can write (assuming your list is named l)

[d['value'] for d in l]

If value might be missing, you can use

[d['value'] for d in l if 'value' in d]

How to preserve insertion order in HashMap?

LinkedHashMap is precisely what you're looking for.

It is exactly like HashMap, except that when you iterate over it, it presents the items in the insertion order.

I am getting "java.lang.ClassNotFoundException: com.google.gson.Gson" error even though it is defined in my classpath

In case of a JSP/Servlet webapplication, you just need to drop 3rd party JAR files in /WEB-INF/lib folder. If the project is a Dynamic Web Project, then Eclipse will automatically take care about setting the buildpath right as well. You do not need to fiddle with Eclipse buildpath. Don't forget to undo it all.

File opens instead of downloading in internet explorer in a href link

This must be a matter of http headers.

see here: HTTP Headers for File Downloads

The server should tell your browser to download the file by sending

Content-Type: application/octet-stream; 
Content-Disposition: attachment;

in the headers

How to establish a connection pool in JDBC?

As answered by others, you will probably be happy with Apache Dbcp or c3p0. Both are popular, and work fine.

Regarding your doubt

Doesn't javax.sql or java.sql have pooled connection implementations? Why wouldn't it be best to use these?

They don't provide implementations, rather interfaces and some support classes, only revelant to the programmers that implement third party libraries (pools or drivers). Normally you don't even look at that. Your code should deal with the connections from your pool just as they were "plain" connections, in a transparent way.

Creating a div element inside a div element in javascript

'b' should be in capital letter in document.getElementById modified code jsfiddle

function test()
{

var element = document.createElement("div");
element.appendChild(document.createTextNode('The man who mistook his wife for a hat'));
document.getElementById('lc').appendChild(element);
 //document.body.appendChild(element);
 }

method in class cannot be applied to given types

The generateNumbers(int[] numbers) function definition has arguments (int[] numbers)that expects an array of integers. However, in the main, generateNumbers(); doesn't have any arguments.

To resolve it, simply add an array of numbers to the arguments while calling thegenerateNumbers() function in the main.

how to call javascript function in html.actionlink in asp.net mvc?

@Html.ActionLink("Edit","ActionName",new{id=item.id},new{onclick="functionname();"})

Access the css ":after" selector with jQuery

You can't manipulate :after, because it's not technically part of the DOM and therefore is inaccessible by any JavaScript. But you can add a new class with a new :after specified.

CSS:

.pageMenu .active.changed:after { 
/* this selector is more specific, so it takes precedence over the other :after */
    border-top-width: 22px;
    border-left-width: 22px;
    border-right-width: 22px;
}

JS:

$('.pageMenu .active').toggleClass('changed');

UPDATE: while it's impossible to directly modify the :after content, there are ways to read and/or override it using JavaScript. See "Manipulating CSS pseudo-elements using jQuery (e.g. :before and :after)" for a comprehensive list of techniques.

C - freeing structs

First you should know, how much memory is allocated when you define and allocate memory in below case.

   typedef struct person{
       char firstName[100], surName[51]
  } PERSON;
  PERSON *testPerson = (PERSON*) malloc(sizeof(PERSON));

1) The sizeof(PERSON) now returns 151 bytes (Doesn't include padding)

2) The memory of 151 bytes is allocated in heap.

3) To free, call free(testPerson).

but If you declare your structure as

  typedef struct person{
      char *firstName, *surName;
  } PERSON;
  PERSON *testPerson = (PERSON*) malloc(sizeof(PERSON));

then

1) The sizeof(PERSON) now returns 8 bytes (Doesn't include padding)

2) Need to allocate memory for firstName and surName by calling malloc() or calloc(). like

        testPerson->firstName = (char *)malloc(100);

3) To free, first free the members in the struct than free the struct. i.e, free(testPerson->firstName); free(testPerson->surName); free(testPerson);

Calling a rest api with username and password - how to

You can also use the RestSharp library for example

var userName = "myuser";
var password = "mypassword";
var host = "170.170.170.170:333";
var client = new RestClient("https://" + host + "/method1");            
client.Authenticator = new HttpBasicAuthenticator(userName, password);            
var request = new RestRequest(Method.POST); 
request.AddHeader("Accept", "application/json");
request.AddHeader("Cache-Control", "no-cache");
request.AddHeader("Content-Type", "application/json");            
request.AddParameter("application/json","{}",ParameterType.RequestBody);
IRestResponse response = client.Execute(request);

file_get_contents("php://input") or $HTTP_RAW_POST_DATA, which one is better to get the body of JSON request?

Your second question is easy, GET has a size limitation of 1-2 kilobytes on both the server and browser side, so any kind of larger amounts of data you'd have to send through POST.

Change SQLite database mode to read-write

To share personal experience I encountered with this error that eventually fix both. Might not necessarily be related to your issue but it appears this error is so generic that it can be attributed to gazillion things.

  1. Database instance open in another application. My DB appeared to have been in a "locked" state so it transition to read only mode. I was able to track it down by stopping the a 2nd instance of the application sharing the DB.

  2. Directory tree permission - please be sure to ensure user account has permission not just at the file level but at the entire upper directory level all the way to / level.

Thanks

JSON Stringify changes time of date because of UTC

Got around this issue by using the moment.js library (the non-timezone version).

var newMinDate = moment(datePicker.selectedDates[0]);
var newMaxDate = moment(datePicker.selectedDates[1]);

// Define the data to ask the server for
var dataToGet = {"ArduinoDeviceIdentifier":"Temperatures",
                "StartDate":newMinDate.format('YYYY-MM-DD HH:mm'),
                "EndDate":newMaxDate.format('YYYY-MM-DD HH:mm')
};

alert(JSON.stringify(dataToGet));

I was using the flatpickr.min.js library. The time of the resulting JSON object created matches the local time provided but the date picker.

How many concurrent AJAX (XmlHttpRequest) requests are allowed in popular browsers?

Wrote my own test. tested the code on stackoverflow, works fine tells me that chrome/FF can do 6

var change = 0;
var simultanius = 0;
var que = 20; // number of tests

Array(que).join(0).split(0).forEach(function(a,i){
    var xhr = new XMLHttpRequest;
    xhr.open("GET", "/?"+i); // cacheBust
    xhr.onreadystatechange = function() {
        if(xhr.readyState == 2){
            change++;
            simultanius = Math.max(simultanius, change);
        }
        if(xhr.readyState == 4){
            change--;
            que--;
            if(!que){
                console.log(simultanius);
            }
        }
    };
    xhr.send();
});

it works for most websites that can trigger readystate change event at different times. (aka: flushing)

I notice on my node.js server that i had to output at least 1025 bytes to trigger the event/flush. otherwise the events would just trigger all three state at once when the request is complete so here is my backend:

var app = require('express')();

app.get("/", function(req,res) {
    res.write(Array(1025).join("a"));
    setTimeout(function() {
        res.end("a");
    },500);
});

app.listen(80);

Update

I notice that You can now have up to 2x request if you are using both xhr and fetch api at the same time

_x000D_
_x000D_
var change = 0;_x000D_
var simultanius = 0;_x000D_
var que = 30; // number of tests_x000D_
_x000D_
Array(que).join(0).split(0).forEach(function(a,i){_x000D_
    fetch("/?b"+i).then(r => {_x000D_
        change++;_x000D_
        simultanius = Math.max(simultanius, change);_x000D_
        return r.text()_x000D_
    }).then(r => {_x000D_
        change--;_x000D_
        que--;_x000D_
        if(!que){_x000D_
            console.log(simultanius);_x000D_
        }_x000D_
    });_x000D_
});_x000D_
_x000D_
Array(que).join(0).split(0).forEach(function(a,i){_x000D_
    var xhr = new XMLHttpRequest;_x000D_
    xhr.open("GET", "/?a"+i); // cacheBust_x000D_
    xhr.onreadystatechange = function() {_x000D_
        if(xhr.readyState == 2){_x000D_
            change++;_x000D_
            simultanius = Math.max(simultanius, change);_x000D_
        }_x000D_
        if(xhr.readyState == 4){_x000D_
            change--;_x000D_
            que--;_x000D_
            if(!que){_x000D_
                document.body.innerHTML = simultanius;_x000D_
            }_x000D_
        }_x000D_
    };_x000D_
    xhr.send();_x000D_
});
_x000D_
_x000D_
_x000D_

How to put labels over geom_bar for each bar in R with ggplot2

To add to rcs' answer, if you want to use position_dodge() with geom_bar() when x is a POSIX.ct date, you must multiply the width by 86400, e.g.,

ggplot(data=dat, aes(x=Types, y=Number, fill=sample)) + 
 geom_bar(position = "dodge", stat = 'identity') +
 geom_text(aes(label=Number), position=position_dodge(width=0.9*86400), vjust=-0.25)

What's the syntax for mod in java

you should examine the specification before using 'remainder' operator % :

http://java.sun.com/docs/books/jls/third_edition/html/expressions.html#15.17.3

// bad enough implementation of isEven method, for fun. so any worse?
boolean isEven(int num)
{
    num %= 10;
    if(num == 1)
       return false;
    else if(num == 0)
       return true;
    else
       return isEven(num + 2);
}
isEven = isEven(a);

How to navigate to a section of a page

My Solutions:

$("body").scrollspy({ target: ".target", offset: fix_header_height });

$(".target").click(function() {
 $("body").animate(
  {
   scrollTop: $($(this).attr("href")).offset().top - fix_header_height
  },
  500
 );
 return;
});

Pandas df.to_csv("file.csv" encode="utf-8") still gives trash characters for minus sign

Your "bad" output is UTF-8 displayed as CP1252.

On Windows, many editors assume the default ANSI encoding (CP1252 on US Windows) instead of UTF-8 if there is no byte order mark (BOM) character at the start of the file. While a BOM is meaningless to the UTF-8 encoding, its UTF-8-encoded presence serves as a signature for some programs. For example, Microsoft Office's Excel requires it even on non-Windows OSes. Try:

df.to_csv('file.csv',encoding='utf-8-sig')

That encoder will add the BOM.

Dynamically Add C# Properties at Runtime

you could deserialize your json string into a dictionary and then add new properties then serialize it.

 var jsonString = @"{}";

        var jsonDoc = JsonSerializer.Deserialize<Dictionary<string, object>>(jsonString);

        jsonDoc.Add("Name", "Khurshid Ali");

        Console.WriteLine(JsonSerializer.Serialize(jsonDoc));

How do I filter an array with TypeScript in Angular 2?

To filter an array irrespective of the property type (i.e. for all property types), we can create a custom filter pipe

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: "filter" })
export class ManualFilterPipe implements PipeTransform {
  transform(itemList: any, searchKeyword: string) {
    if (!itemList)
      return [];
    if (!searchKeyword)
      return itemList;
    let filteredList = [];
    if (itemList.length > 0) {
      searchKeyword = searchKeyword.toLowerCase();
      itemList.forEach(item => {
        //Object.values(item) => gives the list of all the property values of the 'item' object
        let propValueList = Object.values(item);
        for(let i=0;i<propValueList.length;i++)
        {
          if (propValueList[i]) {
            if (propValueList[i].toString().toLowerCase().indexOf(searchKeyword) > -1)
            {
              filteredList.push(item);
              break;
            }
          }
        }
      });
    }
    return filteredList;
  }
}

//Usage

//<tr *ngFor="let company of companyList | filter: searchKeyword"></tr>

Don't forget to import the pipe in the app module

We might need to customize the logic to filer with dates.

How to dynamically set bootstrap-datepicker's date value?

For datetimepickers use this this work for me

$('#lastdate1').data({date: '2016-07-05'});
$('#lastdate1').datetimepicker('update');
$('#lastdate1').datetimepicker().children('input').val('2016-07-05');

How to display tables on mobile using Bootstrap?

After researching for almost 1 month i found the below code which is working very beautifully and 100% perfectly on my website. To check the preview how it is working you can check from the link. https://www.jobsedit.in/state-government-jobs/

CSS CODE-----

@media only screen and (max-width: 500px)  {
    .resp table  { 
        display: block ; 
    }   
    .resp th  { 
        position: absolute;
        top: -9999px;
        left: -9999px;
        display:block ;
    }   
     .resp tr { 
    border: 1px solid #ccc;
    display:block;
    }   
    .resp td  { 
        /* Behave  like a "row" */
        border: none;
        border-bottom: 1px solid #eee; 
        position: relative;
        width:100%;
        background-color:White;
        text-indent: 50%; 
        text-align:left;
        padding-left: 0px;
        display:block;      
    }
    .resp  td:nth-child(1)  {
        border: none;
        border-bottom: 1px solid #eee; 
        position: relative;
        font-size:20px;
        text-indent: 0%;
        text-align:center;
}   
    .resp td:before  { 
        /* Now like a table header */
        position: absolute;
        /* Top/left values mimic padding */
        top: 6px;
        left: 6px;
        width: 45%; 
        text-indent: 0%;
        text-align:left;
        white-space: nowrap;
        background-color:White;
        font-weight:bold;
    }
    /*
    Label the data
    */
    .resp td:nth-of-type(2):before  { content: attr(data-th) }
    .resp td:nth-of-type(3):before  { content: attr(data-th) }
    .resp td:nth-of-type(4):before  { content: attr(data-th) }
    .resp td:nth-of-type(5):before  { content: attr(data-th) }
    .resp td:nth-of-type(6):before  { content: attr(data-th) }
    .resp td:nth-of-type(7):before  { content: attr(data-th) }
    .resp td:nth-of-type(8):before  { content: attr(data-th) }
    .resp td:nth-of-type(9):before  { content: attr(data-th) }
    .resp td:nth-of-type(10):before  { content: attr(data-th) }
}

HTML CODE --

<table>
<tr>
<td data-th="Heading 1"></td>
<td data-th="Heading 2"></td>
<td data-th="Heading 3"></td>
<td data-th="Heading 4"></td>
<td data-th="Heading 5"></td>
</tr>
</table>

How to browse localhost on Android device?

If you want to access a server running on your PC from your Android device via your wireless network, first run the command ipconfig on your PC (use run (Windows logo + R), cmd, ipconfig).

Note the IPv4 address: (it should be 192.168.0.x) for some x. Use this as the server IP address, together with the port number, e.g. 192.168.0.7:8080, in your code.

Your Android device will then access the server via your wireless network router.

How do I get the SelectedItem or SelectedIndex of ListView in vb.net?

ListView.FocusedItem.Index 

or you can use foreach loop like this

int index= -1;
foreach (ListViewItem itm in listView1.SelectedItems)
{
    if (itm.Selected)
    {
        index= itm.Index;
    }
}

Username and password in https url

When you put the username and password in front of the host, this data is not sent that way to the server. It is instead transformed to a request header depending on the authentication schema used. Most of the time this is going to be Basic Auth which I describe below. A similar (but significantly less often used) authentication scheme is Digest Auth which nowadays provides comparable security features.

With Basic Auth, the HTTP request from the question will look something like this:

GET / HTTP/1.1
Host: example.com
Authorization: Basic Zm9vOnBhc3N3b3Jk

The hash like string you see there is created by the browser like this: base64_encode(username + ":" + password).

To outsiders of the HTTPS transfer, this information is hidden (as everything else on the HTTP level). You should take care of logging on the client and all intermediate servers though. The username will normally be shown in server logs, but the password won't. This is not guaranteed though. When you call that URL on the client with e.g. curl, the username and password will be clearly visible on the process list and might turn up in the bash history file.

When you send passwords in a GET request as e.g. http://example.com/login.php?username=me&password=secure the username and password will always turn up in server logs of your webserver, application server, caches, ... unless you specifically configure your servers to not log it. This only applies to servers being able to read the unencrypted http data, like your application server or any middleboxes such as loadbalancers, CDNs, proxies, etc. though.

Basic auth is standardized and implemented by browsers by showing this little username/password popup you might have seen already. When you put the username/password into an HTML form sent via GET or POST, you have to implement all the login/logout logic yourself (which might be an advantage and allows you to more control over the login/logout flow for the added "cost" of having to implement this securely again). But you should never transfer usernames and passwords by GET parameters. If you have to, use POST instead. The prevents the logging of this data by default.

When implementing an authentication mechanism with a user/password entry form and a subsequent cookie-based session as it is commonly used today, you have to make sure that the password is either transported with POST requests or one of the standardized authentication schemes above only.

Concluding I could say, that transfering data that way over HTTPS is likely safe, as long as you take care that the password does not turn up in unexpected places. But that advice applies to every transfer of any password in any way.

Redirect with CodeIgniter

redirect()

URL Helper


The redirect statement in code igniter sends the user to the specified web page using a redirect header statement.

This statement resides in the URL helper which is loaded in the following way:

$this->load->helper('url');

The redirect function loads a local URI specified in the first parameter of the function call and built using the options specified in your config file.

The second parameter allows the developer to use different HTTP commands to perform the redirect "location" or "refresh".

According to the Code Igniter documentation: "Location is faster, but on Windows servers it can sometimes be a problem."

Example:

if ($user_logged_in === FALSE)
{
     redirect('/account/login', 'refresh');
}

How do I break out of a loop in Perl?

Additional data (in case you have more questions):

FOO: {
       for my $i ( @listone ){
          for my $j ( @listtwo ){
                 if ( cond( $i,$j ) ){

                    last FOO;  # --->
                                   # |
                 }                 # |
          }                        # |
       }                           # |
 } # <-------------------------------

Delete all lines starting with # or ; in Notepad++

Find:

^[#;].*

Replace with nothing. The ^ indicates the start of a line, the [#;] is a character class to match either # or ;, and .* matches anything else in the line.

In versions of Notepad++ before 6.0, you won't be able to actually remove the lines due to a limitation in its regex engine; the replacement results in blank lines for each line matched. In other words, this:

# foo
; bar
statement;

Will turn into:



statement;

However, the replacement will work in Notepad++ 6.0 if you add \r, \n or \r\n to the end of the pattern, depending on which line ending your file is using, resulting in:

statement;

What is the correct way of reading from a TCP socket in C/C++?

1) Others (especially dirkgently) have noted that buffer needs to be allocated some memory space. For smallish values of N (say, N <= 4096), you can also allocate it on the stack:

#define BUFFER_SIZE 4096
char buffer[BUFFER_SIZE]

This saves you the worry of ensuring that you delete[] the buffer should an exception be thrown.

But remember that stacks are finite in size (so are heaps, but stacks are finiter), so you don't want to put too much there.

2) On a -1 return code, you should not simply return immediately (throwing an exception immediately is even more sketchy.) There are certain normal conditions that you need to handle, if your code is to be anything more than a short homework assignment. For example, EAGAIN may be returned in errno if no data is currently available on a non-blocking socket. Have a look at the man page for read(2).

How to execute a shell script from C in Linux?

If you're ok with POSIX, you can also use popen()/pclose()

#include <stdio.h>
#include <stdlib.h>

int main(void) {
/* ls -al | grep '^d' */
  FILE *pp;
  pp = popen("ls -al", "r");
  if (pp != NULL) {
    while (1) {
      char *line;
      char buf[1000];
      line = fgets(buf, sizeof buf, pp);
      if (line == NULL) break;
      if (line[0] == 'd') printf("%s", line); /* line includes '\n' */
    }
    pclose(pp);
  }
  return 0;
}

Removing an element from an Array (Java)

Use an ArrayList:

alist.remove(1); //removes the element at position 1

Create a new Ruby on Rails application using MySQL instead of SQLite

If you already have a rails project, change the adapter in the config/database.yml file to mysql and make sure you specify a valid username and password, and optionally, a socket:

development:
  adapter: mysql2
  database: db_name_dev
  username: koploper
  password:
  host: localhost
  socket: /tmp/mysql.sock

Next, make sure you edit your Gemfile to include the mysql2 or activerecord-jdbcmysql-adapter (if using jruby).

Fast way to concatenate strings in nodeJS/JavaScript

You asked about performance. See this perf test comparing 'concat', '+' and 'join' - in short the + operator wins by far.

ImportError: No module named PyQt4

You have to check which Python you are using. I had the same problem because the Python I was using was not the same one that brew was using. In your command line:

  1. which python
    output: /usr/bin/python
  2. which brew
    output: /usr/local/bin/brew     //so they are different
  3. cd /usr/local/lib/python2.7/site-packages
  4. ls   //you can see PyQt4 and sip are here
  5. Now you need to add usr/local/lib/python2.7/site-packages to your python path.
  6. open ~/.bash_profile   //you will open your bash_profile file in your editor
  7. Add 'export PYTHONPATH=/usr/local/lib/python2.7/site-packages:$PYTHONPATH' to your bash file and save it
  8. Close your terminal and restart it to reload the shell
  9. python
  10. import PyQt4    // it is ok now

Converting a column within pandas dataframe from int to string

In [16]: df = DataFrame(np.arange(10).reshape(5,2),columns=list('AB'))

In [17]: df
Out[17]: 
   A  B
0  0  1
1  2  3
2  4  5
3  6  7
4  8  9

In [18]: df.dtypes
Out[18]: 
A    int64
B    int64
dtype: object

Convert a series

In [19]: df['A'].apply(str)
Out[19]: 
0    0
1    2
2    4
3    6
4    8
Name: A, dtype: object

In [20]: df['A'].apply(str)[0]
Out[20]: '0'

Don't forget to assign the result back:

df['A'] = df['A'].apply(str)

Convert the whole frame

In [21]: df.applymap(str)
Out[21]: 
   A  B
0  0  1
1  2  3
2  4  5
3  6  7
4  8  9

In [22]: df.applymap(str).iloc[0,0]
Out[22]: '0'

df = df.applymap(str)

Neither BindingResult nor plain target object for bean name available as request attribute

I had a similar problem in IntelliJ IDEA. My code was 100% correct, but after starting the Tomcat, you receive an exception. java.lang.IllegalStateException: Neither BindingResult

I just removed and added again Tomcat configuration. And it worked for me.

A picture Tomcat configuration

enter image description here

What's the UIScrollView contentInset property for?

It sets the distance of the inset between the content view and the enclosing scroll view.

Obj-C

aScrollView.contentInset = UIEdgeInsetsMake(0, 0, 0, 7.0);

Swift 5.0

aScrollView.contentInset = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 7.0)

Here's a good iOS Reference Library article on scroll views that has an informative screenshot (fig 1-3) - I'll replicate it via text here:

  _|?_cW_?_|_?_
   |       | 
---------------
   |content| ?
 ? |content| contentInset.top
cH |content|
 ? |content| contentInset.bottom
   |content| ?
---------------
  _|_______|___ 
             ?


   (cH = contentSize.height; cW = contentSize.width)

The scroll view encloses the content view plus whatever padding is provided by the specified content insets.

What to do about Eclipse's "No repository found containing: ..." error messages?

Quick answer

Go to Help → Install new software → Here uncheck “Contact all update sites during install to find required software”

Eclipse will prompt that the content isn't authorized or something like that. just ignore and continue. then everything will be OK.

At least this trick resolved my problems similar like this:

An error occurred while collecting items to be installed session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=). No repository found containing: osgi.bundle,org.eclipse.emf,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.ant,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.codegen,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.codegen.ecore,2.8.1.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.codegen.ecore.ui,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.codegen.ui,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.common,2.8.0.v20120911-0500 No repository found containing: osgi.bundle,org.eclipse.emf.common.ui,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.converter,2.5.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.databinding,1.2.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.databinding.edit,1.2.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.ecore,2.8.1.v20120911-0500 No repository found containing: osgi.bundle,org.eclipse.emf.ecore.change,2.8.0.v20120911-0500 No repository found containing: osgi.bundle,org.eclipse.emf.ecore.change.edit,2.5.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.ecore.edit,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.ecore.editor,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.ecore.xmi,2.8.0.v20120911-0500 No repository found containing: osgi.bundle,org.eclipse.emf.edit,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.edit.ui,2.8.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.exporter,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.importer,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.importer.ecore,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.importer.java,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.importer.rose,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore.editor,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore2ecore,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore2ecore.editor,2.5.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore2xml,2.7.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ecore2xml.ui,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.emf.mapping.ui,2.6.0.v20120917-0436 No repository found containing: osgi.bundle,org.eclipse.wst.common.project.facet.core,1.4.300.v201111030424 No repository found containing: osgi.bundle,org.eclipse.wst.common.project.facet.ui,1.4.300.v201111030424 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.codegen.ecore,2.8.1.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.codegen.ecore.ui,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.codegen,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.codegen.ui,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.common,2.8.0.v20120911-0500 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.common.ui,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.converter,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.databinding.edit,1.2.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.databinding,1.2.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.ecore.edit,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.ecore.editor,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.ecore,2.8.1.v20120911-0500 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.edit,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.edit.ui,2.8.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf,2.8.1.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.mapping.ecore.editor,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.mapping.ecore,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.mapping,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.emf.mapping.ui,2.7.0.v20120917-0436 No repository found containing: org.eclipse.update.feature,org.eclipse.wst.common.fproj,3.4.0.v201202292300-377F8N8s735555393B7B

Convert timestamp to date in MySQL query

you can try this
The date is of timestamp type which has the following format: ‘YYYY-MM-DD HH:MM:SS’ or ‘2008-10-05 21:34:02.’

$res = mysql_query("SELECT date FROM times;");
while ( $row = mysql_fetch_array($res) ) {
   echo $row['date'] . "
";
}

The PHP strtotime function parses the MySQL timestamp into a Unix timestamp which can be utilized for further parsing or formatting in the PHP date function.

Here are some other sample date output formats that may be of practical use:

echo date("F j, Y g:i a", strtotime($row["date"]));                  // October 5, 2008 9:34 pm
echo date("m.d.y", strtotime($row["date"]));                         // 10.05.08
echo date("j, n, Y", strtotime($row["date"]));                       // 5, 10, 2008
echo date("Ymd", strtotime($row["date"]));                           // 20081005
echo date('\i\t \i\s \t\h\e jS \d\a\y.', strtotime($row["date"]));   // It is the 5th day.
echo date("D M j G:i:s T Y", strtotime($row["date"]));               // Sun Oct 5 21:34:02 PST 2008

How to force table cell <td> content to wrap?

if you want to wrap the data in td then you can use the below code

td{
    width:60%;
    word-break: break-word;
    }

How to hash some string with sha256 in Java?

Full example hash to string as another string.

public static String sha256(String base) {
    try{
        MessageDigest digest = MessageDigest.getInstance("SHA-256");
        byte[] hash = digest.digest(base.getBytes("UTF-8"));
        StringBuffer hexString = new StringBuffer();

        for (int i = 0; i < hash.length; i++) {
            String hex = Integer.toHexString(0xff & hash[i]);
            if(hex.length() == 1) hexString.append('0');
            hexString.append(hex);
        }

        return hexString.toString();
    } catch(Exception ex){
       throw new RuntimeException(ex);
    }
}

How to check Django version

There are various ways to get the Django version. You can use any one of the following given below according to your requirements.

Note: If you are working in a virtual environment then please load your python environment


Terminal Commands

  1. python -m django --version
  2. django-admin --version or django-admin.py version
  3. ./manage.py --version or python manage.py --version
  4. pip freeze | grep Django
  5. python -c "import django; print(django.get_version())"
  6. python manage.py runserver --version

Django Shell Commands

  1. import django django.get_version() OR django.VERSION
  2. from django.utils import version version.get_version() OR version.get_complete_version()
  3. import pkg_resources pkg_resources.get_distribution('django').version

(Feel free to modify this answer, if you have some kind of correction or you want to add more related information.)

Automatically creating directories with file output

The os.makedirs function does this. Try the following:

import os
import errno

filename = "/foo/bar/baz.txt"
if not os.path.exists(os.path.dirname(filename)):
    try:
        os.makedirs(os.path.dirname(filename))
    except OSError as exc: # Guard against race condition
        if exc.errno != errno.EEXIST:
            raise

with open(filename, "w") as f:
    f.write("FOOBAR")

The reason to add the try-except block is to handle the case when the directory was created between the os.path.exists and the os.makedirs calls, so that to protect us from race conditions.


In Python 3.2+, there is a more elegant way that avoids the race condition above:

import os

filename = "/foo/bar/baz.txt"
os.makedirs(os.path.dirname(filename), exist_ok=True)
with open(filename, "w") as f:
    f.write("FOOBAR")

How to open the terminal in Atom?

For Windows follow the below steps

(1)go to file>setting and click on install enter image description here

(2) then type "platformio-ide-terminal" in packages and hit install enter image description here (3) after finish install restart atom and press

 ctrl + ~ for opening the terminal `~` is the key below `Esc`

enter image description here

welcome ;-)

jquery - fastest way to remove all rows from a very large table

$("#your-table-id").empty();

That's as fast as you get.

How do I completely rename an Xcode project (i.e. inclusive of folders)?

Adding to the accepted answer by Luke West. If you have any entitlements:

  1. Close Xcode
  2. Change the entitlements filename
  3. Go into Xcode, select the entitlements file should be highlighted red, in the File inspector select the Folder icon and select your renamed file.
  4. Go into Build Settings, and search "entitlements" and update the folder name and file name for the entitlement.
  5. Clean and rebuild

Is there an eval() function in Java?

With Java 9, we get access to jshell, so one can write something like this:

import jdk.jshell.JShell;
import java.lang.StringBuilder;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;

public class Eval {
    public static void main(String[] args) throws IOException {
        try(JShell js = JShell.create(); BufferedReader br = new BufferedReader(new InputStreamReader(System.in))) {

            js.onSnippetEvent(snip -> {
                if (snip.status() == jdk.jshell.Snippet.Status.VALID) {
                    System.out.println("? " + snip.value());
                }
            });

            System.out.print("> ");
            for (String line = br.readLine(); line != null; line = br.readLine()) {
                js.eval(js.sourceCodeAnalysis().analyzeCompletion(line).source());
                System.out.print("> ");
            }
        }
    }
}

Sample run:

> 1 + 2 / 4 * 3
? 1
> 32 * 121
? 3872
> 4 * 5
? 20
> 121 * 51
? 6171
>

Slightly op, but that's what Java currently has to offer

How can I tell where mongoDB is storing data? (its not in the default /data/db!)

While this question is targeted for Linux/Unix instances of Mongo, it's one of the first search results regardless of the operating system used, so for future Windows users that find this:

If MongoDB is set up as a Windows Service in the default manner, you can usually find it by looking at the 'Path to executable' entry in the MongoDB Service's Properties:

Properties Window showing 'Path to Executable' option

PHP: Get key from array?

Another way to use key($array) in a foreach loop is by using next($array) at the end of the loop, just make sure each iteration calls the next() function (in case you have complex branching inside the loop)

How to use UTF-8 in resource properties with ResourceBundle

Here's a Java 7 solution that uses Guava's excellent support library and the try-with-resources construct. It reads and writes properties files using UTF-8 for the simplest overall experience.

To read a properties file as UTF-8:

File file =  new File("/path/to/example.properties");

// Create an empty set of properties
Properties properties = new Properties();

if (file.exists()) {

  // Use a UTF-8 reader from Guava
  try (Reader reader = Files.newReader(file, Charsets.UTF_8)) {
    properties.load(reader);
  } catch (IOException e) {
    // Do something
  }
}

To write a properties file as UTF-8:

File file =  new File("/path/to/example.properties");

// Use a UTF-8 writer from Guava
try (Writer writer = Files.newWriter(file, Charsets.UTF_8)) {
  properties.store(writer, "Your title here");
  writer.flush();
} catch (IOException e) {
  // Do something
}

Curl command line for consuming webServices?

If you want a fluffier interface than the terminal, http://hurl.it/ is awesome.

Angularjs if-then-else construction in expression

You can easily use ng-show such as :

    <div ng-repeater="item in items">
        <div>{{item.description}}</div>
        <div ng-show="isExists(item)">available</div>
        <div ng-show="!isExists(item)">oh no, you don't have it</div>
    </div>

For more complex tests, you can use ng-switch statements :

    <div ng-repeater="item in items">
        <div>{{item.description}}</div>
        <div ng-switch on="isExists(item)">
            <span ng-switch-when="true">Available</span>
            <span ng-switch-default>oh no, you don't have it</span>
        </div>
    </div>

How to write to an existing excel file without overwriting data (using pandas)?

There is a better solution in pandas 0.24:

with pd.ExcelWriter(path, mode='a') as writer:
    s.to_excel(writer, sheet_name='another sheet', index=False)

before:

enter image description here

after:

enter image description here

so upgrade your pandas now:

pip install --upgrade pandas

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

In Java 7 you have the new Paths api. The modern and cleanest solution is:

Paths.get("C:/aaa/bbb/ccc/ddd/test.java").getParent().getFileName();

Result would be:

C:/aaa/bbb/ccc/ddd