Programs & Examples On #Setrlimit

system call included in POSIX which allows setting of limits on operating system resources like CPU, memory, files and possibly others

How to disable horizontal scrolling of UIScrollView?

Use this single line.

self.automaticallyAdjustsScrollViewInsets = NO;

how to create insert new nodes in JsonNode?

These methods are in ObjectNode: the division is such that most read operations are included in JsonNode, but mutations in ObjectNode and ArrayNode.

Note that you can just change first line to be:

ObjectNode jNode = mapper.createObjectNode();
// version ObjectMapper has should return ObjectNode type

or

ObjectNode jNode = (ObjectNode) objectCodec.createObjectNode();
// ObjectCodec is in core part, must be of type JsonNode so need cast

Why am I getting the error "connection refused" in Python? (Sockets)

I was being able to ping my connection but was STILL getting the 'connection refused' error. Turns out I was pinging myself! That's what the problem was.

Fake "click" to activate an onclick method

var clickEvent = new MouseEvent('click', {
  view: window,
  bubbles: true,
  cancelable: true
});
var element = document.getElementById('element-id'); 
var cancelled = !element.dispatchEvent(clickEvent);
if (cancelled) {
  // A handler called preventDefault.
  alert("cancelled");
} else {
  // None of the handlers called preventDefault.
  alert("not cancelled");
}

element.dispatchEvent is supported in all major browsers. The example above is based on an sample simulateClick() function on MDN.

CMD what does /im (taskkill)?

it allows you to kill a task based on the image name like taskkill /im iexplore.exe or taskkill /im notepad.exe

Python 3 sort a dict by its values

To sort a dictionary and keep it functioning as a dictionary afterwards, you could use OrderedDict from the standard library.

If that's not what you need, then I encourage you to reconsider the sort functions that leave you with a list of tuples. What output did you want, if not an ordered list of key-value pairs (tuples)?

How to use PDO to fetch results array in PHP?

Take a look at the PDOStatement.fetchAll method. You could also use fetch in an iterator pattern.

Code sample for fetchAll, from the PHP documentation:

<?php
$sth = $dbh->prepare("SELECT name, colour FROM fruit");
$sth->execute();

/* Fetch all of the remaining rows in the result set */
print("Fetch all of the remaining rows in the result set:\n");
$result = $sth->fetchAll(\PDO::FETCH_ASSOC);
print_r($result);

Results:

Array
(
    [0] => Array
        (
            [NAME] => pear
            [COLOUR] => green
        )

    [1] => Array
        (
            [NAME] => watermelon
            [COLOUR] => pink
        )
)

PHP php_network_getaddresses: getaddrinfo failed: No such host is known

Your "localhost" cannot resolve the name www.google.com, which means your machine doesn't/can't reach a valid dns server.

Try ping google.com on the console of that machine to verify this.

Empty ArrayList equals null

Just as zero is a number - just a number that represents none - an empty list is still a list, just a list with nothing in it. null is no list at all; it's therefore different from an empty list.

Similarly, a list that contains null items is a list, and is not an empty list. Because it has items in it; it doesn't matter that those items are themselves null. As an example, a list with three null values in it, and nothing else: what is its length? Its length is 3. The empty list's length is zero. And, of course, null doesn't have a length.

What is Options +FollowSymLinks?

Parameter Options FollowSymLinks enables you to have a symlink in your webroot pointing to some other file/dir. With this disabled, Apache will refuse to follow such symlink. More secure Options SymLinksIfOwnerMatch can be used instead - this will allow you to link only to other files which you do own.

If you use Options directive in .htaccess with parameter which has been forbidden in main Apache config, server will return HTTP 500 error code.

Allowed .htaccess options are defined by directive AllowOverride in the main Apache config file. To allow symlinks, this directive need to be set to All or Options.

Besides allowing use of symlinks, this directive is also needed to enable mod_rewrite in .htaccess context. But for this, also the more secure SymLinksIfOwnerMatch option can be used.

using lodash .groupBy. how to add your own keys for grouped output?

I would suggest a different approach, using my own library you could do this in a few lines:

var groupMe = sequence(
  groupBy(pluck('color')),
  forOwn(function(acc, k, v) {
    acc.push({colors: k, users: v});
    return acc;
  },[])
);

var result = groupMe(collection);

This would a be a bit difficult with lodash or Underscore because the arguments are in the opposite order order, so you'd have to use _.partial a lot.

Sublime 3 - Set Key map for function Goto Definition

If you want to see how to do a proper definition go into Sublime Text->Preferences->Key Bindings - Default and search for the command you want to override.

{ "keys": ["f12"], "command": "goto_definition" },
{ "keys": ["super+alt+down"], "command": "goto_definition" }

Those are two that show in my Default.

On Mac I copied the second to override.

in Sublime Text -> Preferences -> Key Bindings - User I added this

/* Beginning of File */

[
    {
        "keys": ["super+shift+i"], "command": "goto_definition" 
    }
]

/* End of File */

This binds it to the Command + Shift + 1 combination on mac.

Scroll / Jump to id without jQuery

below code might help you

var objControl=document.getElementById("divid");
objControl.scrollTop = objControl.offsetTop;

How can I listen for keypress event on the whole page?

If you want to perform any event on any specific keyboard button press, in that case, you can use @HostListener. For this, you have to import HostListener in your component ts file.

import { HostListener } from '@angular/core';
then use below function anywhere in your component ts file.

@HostListener('document:keyup', ['$event'])
  handleDeleteKeyboardEvent(event: KeyboardEvent) {
    if(event.key === 'Delete')
    {
      // remove something...
    }
  }

Android Saving created bitmap to directory on sd card

Pass bitmap to the saveImage Method, It will save your bitmap in the name of a saveBitmap, inside created test folder.

private void saveImage(Bitmap data) {
                    File createFolder = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),"test");
                    if(!createFolder.exists())
                    createFolder.mkdir();
                    File saveImage = new File(createFolder,"saveBitmap.jpg");
                    try {
                        OutputStream outputStream = new FileOutputStream(saveImage);
                        data.compress(Bitmap.CompressFormat.JPEG,100,outputStream);
                        outputStream.flush();
                        outputStream.close();
                    } catch (FileNotFoundException e) {
                        e.printStackTrace();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }

and use this:

  saveImage(bitmap);

How to get a product's image in Magento?

If you have the product collection object like:

$collection = Mage::getModel('catalog/product')->getCollection(); 

Now you can get product sku using $_product->getSku() if you can't get image path with

echo $this->helper('catalog/image')->init($_product,'small_image')->resize(135);

Or

$_product->getImageUrl();

Then you can add a little code

$productModel = Mage::getModel('catalog/product');
$_prod = $productModel->loadByAttribute('sku', $_product->getSku()); 
$_prod->getImageUrl();

What is the ellipsis (...) for in this method signature?

The way to use the ellipsis or varargs inside the method is as if it were an array:

public void PrintWithEllipsis(String...setOfStrings) {
    for (String s : setOfStrings)
        System.out.println(s);
}

This method can be called as following:

obj.PrintWithEllipsis(); // prints nothing
obj.PrintWithEllipsis("first"); // prints "first"
obj.PrintWithEllipsis("first", "second"); // prints "first\nsecond"

Inside PrintWithEllipsis, the type of setOfStrings is an array of String. So you could save the compiler some work and pass an array:

String[] argsVar = {"first", "second"};
obj.PrintWithEllipsis(argsVar);

For varargs methods, a sequence parameter is treated as being an array of the same type. So if two signatures differ only in that one declares a sequence and the other an array, as in this example:

void process(String[] s){}
void process(String...s){}

then a compile-time error occurs.

Source: The Java Programming Language specification, where the technical term is variable arity parameter rather than the common term varargs.

How can I get log4j to delete old rotating log files?

There is no default value to control deleting old log files created by DailyRollingFileAppender. But you can write your own custom Appender that deletes old log files in much the same way as setting maxBackupIndex does for RollingFileAppender.

Simple instructions found here

From 1:

If you are trying to use the Apache Log4J DailyRollingFileAppender for a daily log file, you may need to want to specify the maximum number of files which should be kept. Just like rolling RollingFileAppender supports maxBackupIndex. But the current version of Log4j (Apache log4j 1.2.16) does not provide any mechanism to delete old log files if you are using DailyRollingFileAppender. I tried to make small modifications in the original version of DailyRollingFileAppender to add maxBackupIndex property. So, it would be possible to clean up old log files which may not be required for future usage.

Invoking modal window in AngularJS Bootstrap UI using JavaScript

Open modal windows with passing data to dialog

In case if someone interests to pass data to dialog:

app.controller('ModalCtrl', function($scope,  $modal) {
      
      $scope.name = 'theNameHasBeenPassed';

      $scope.showModal = function() {
        
        $scope.opts = {
        backdrop: true,
        backdropClick: true,
        dialogFade: false,
        keyboard: true,
        templateUrl : 'modalContent.html',
        controller : ModalInstanceCtrl,
        resolve: {} // empty storage
          };
          
        
        $scope.opts.resolve.item = function() {
            return angular.copy(
                                {name: $scope.name}
                          ); // pass name to resolve storage
        }
        
          var modalInstance = $modal.open($scope.opts);
          
          modalInstance.result.then(function(){
            //on ok button press 
          },function(){
            //on cancel button press
            console.log("Modal Closed");
          });
      };                   
})

var ModalInstanceCtrl = function($scope, $modalInstance, $modal, item) {
    
     $scope.item = item;
    
      $scope.ok = function () {
        $modalInstance.close();
      };
      
      $scope.cancel = function () {
        $modalInstance.dismiss('cancel');
      };
}

Demo Plunker

What are ODEX files in Android?

The blog article is mostly right, but not complete. To have a full understanding of what an odex file does, you have to understand a little about how application files (APK) work.

Applications are basically glorified ZIP archives. The java code is stored in a file called classes.dex and this file is parsed by the Dalvik JVM and a cache of the processed classes.dex file is stored in the phone's Dalvik cache.

An odex is basically a pre-processed version of an application's classes.dex that is execution-ready for Dalvik. When an application is odexed, the classes.dex is removed from the APK archive and it does not write anything to the Dalvik cache. An application that is not odexed ends up with 2 copies of the classes.dex file--the packaged one in the APK, and the processed one in the Dalvik cache. It also takes a little longer to launch the first time since Dalvik has to extract and process the classes.dex file.

If you are building a custom ROM, it's a really good idea to odex both your framework JAR files and the stock apps in order to maximize the internal storage space for user-installed apps. If you want to theme, then simply deodex -> apply your theme -> reodex -> release.

To actually deodex, use small and baksmali:

https://github.com/JesusFreke/smali/wiki/DeodexInstructions

How to programmatically add controls to a form in VB.NET

To add controls dynamically to the form, do the following code. Here we are creating textbox controls to add dynamically.

Public Class Form1
    Private m_TextBoxes() As TextBox = {}

    Private Sub Button1_Click(ByVal sender As System.Object, _
                              ByVal e As System.EventArgs) _
                              Handles Button1.Click

        ' Get the index for the new control.
        Dim i As Integer = m_TextBoxes.Length

        ' Make room.
        ReDim Preserve m_TextBoxes(i)

        ' Create and initialize the control.
        m_TextBoxes(i) = New TextBox
        With m_TextBoxes(i)
            .Name = "TextBox" & i.ToString()
            If m_TextBoxes.Length < 2 Then
                ' Position the first one.
                .SetBounds(8, 8, 100, 20)
            Else
                ' Position subsequent controls.
                .Left = m_TextBoxes(i - 1).Left
                .Top = m_TextBoxes(i - 1).Top + m_TextBoxes(i - _
                    1).Height + 4
                .Size = m_TextBoxes(i - 1).Size
            End If

            ' Save the control's index in the Tag property.
            ' (Or you can get this from the Name.)
            .Tag = i
        End With

        ' Give the control an event handler.
        AddHandler m_TextBoxes(i).TextChanged, AddressOf TextBox_TextChanged

        ' Add the control to the form.
        Me.Controls.Add(m_TextBoxes(i))
    End Sub

    'When you enter text in one of the TextBoxes, the TextBox_TextChanged event
    'handler displays the control's name and its current text.
    Private Sub TextBox_TextChanged(ByVal sender As  _
    System.Object, ByVal e As System.EventArgs)
        ' Display the current text.
        Dim txt As TextBox = DirectCast(sender, TextBox)
        Debug.WriteLine(txt.Name & ": [" & txt.Text & "]")
    End Sub
End Class

Second line in li starts under the bullet after CSS-reset

I second Dipaks' answer, but often just the text-indent is enough as you may/maynot be positioning the ul for better layout control.

ul li{
text-indent: -1em;
}

BackgroundWorker vs background Thread

I want to point out one behavior of BackgroundWorker class that wasn't mentioned yet. You can make a normal Thread to run in background by setting the Thread.IsBackground property.

Background threads are identical to foreground threads, except that background threads do not prevent a process from terminating. [1]

You can test this behavoir by calling the following method in the constructor of your form window.

void TestBackgroundThread()
{
    var thread = new Thread((ThreadStart)delegate()
    {
        long count = 0;
        while (true)
        {
            count++;
            Debug.WriteLine("Thread loop count: " + count);
        }
    });

    // Choose one option:
    thread.IsBackground = true; // <--- This will make the thread run in background
    thread.IsBackground = false; // <--- This will delay program termination

    thread.Start();
}

When the IsBackground property is set to true and you close the window, then your application will terminate normaly.

But when the IsBackground property is set to false (by default) and you close the window, then just the window will disapear but the process will still keep running.

The BackgroundWorker class utilize a Thread that runs in the background.

Laravel: Error [PDOException]: Could not Find Driver in PostgreSQL

For PHP 7 in Ubuntu you can also do:

sudo apt-get install php7.0-pgsql

So, now you can do not uncomment lines in php.ini

UPD: I have a same error, so problem was not in driver. I changed my database.ini, but every time I saw an error. And I change database config in .env and errors gone.

Add a properties file to IntelliJ's classpath

I spent quite a lot of time figuring out how to do this in Intellij 13x. I apparently never added the properties files to the artifacts that required them, which is a separate step in Intellij. The setup below also works when you have a properties file that is shared by multiple modules.

  • Go to your project setup (CTRL + ALT + SHIFT + S)
  • In the list, select the module that you want to add one or more properties files to.
  • On the right, select the Dependencies tab.
  • Click the green plus and select "Jars or directories".
  • Now select the folder that contains the property file(s). (I haven't tried including an individual file)
  • Intellij will now ask you what the "category" of the selected file is. Choose "classes" (even though they are not).
  • Now you must add the properties files to the artifact. Intellij will give you the shortcut shown below. It will show errors in the red part at the bottom and a 'red lightbulb' that when clicked shows you an option to add the files to the artifact. You can also go to the 'artifacts' section and add the files to the artifacts manually.

enter image description here

How to set text color to a text view programmatically

Great answers. Adding one that loads the color from an Android resources xml but still sets it programmatically:

textView.setTextColor(getResources().getColor(R.color.some_color));

Please note that from API 23, getResources().getColor() is deprecated. Use instead:

textView.setTextColor(ContextCompat.getColor(context, R.color.some_color));

where the required color is defined in an xml as:

<resources>
  <color name="some_color">#bdbdbd</color>
</resources>

Update:

This method was deprecated in API level 23. Use getColor(int, Theme) instead.

Check this.

Android Split string

     String s = "having Community Portal|Help Desk|Local Embassy|Reference Desk|Site News";
     StringTokenizer st = new StringTokenizer(s, "|");
        String community = st.nextToken();
        String helpDesk = st.nextToken(); 
        String localEmbassy = st.nextToken();
        String referenceDesk = st.nextToken();
        String siteNews = st.nextToken();

Convert String to double in Java

Used this to convert any String number to double when u need int just convert the data type from num and num2 to int ; took all the cases for any string double with Eng:"Bader Qandeel"

public static double str2doubel(String str) {
    double num = 0;
    double num2 = 0;
    int idForDot = str.indexOf('.');
    boolean isNeg = false;
    String st;
    int start = 0;
    int end = str.length();

    if (idForDot != -1) {
        st = str.substring(0, idForDot);
        for (int i = str.length() - 1; i >= idForDot + 1; i--) {
            num2 = (num2 + str.charAt(i) - '0') / 10;
        }
    } else {
        st = str;
    }

    if (st.charAt(0) == '-') {
        isNeg = true;
        start++;
    } else if (st.charAt(0) == '+') {
        start++;
    }

    for (int i = start; i < st.length(); i++) {
        if (st.charAt(i) == ',') {
            continue;
        }
        num *= 10;
        num += st.charAt(i) - '0';
    }

    num = num + num2;
    if (isNeg) {
        num = -1 * num;
    }
    return num;
}

How to use orderby with 2 fields in linq?

MyList.OrderBy(x => x.StartDate).ThenByDescending(x => x.EndDate);

Any way to make a WPF textblock selectable?

According to Windows Dev Center:

TextBlock.IsTextSelectionEnabled property

[ Updated for UWP apps on Windows 10. For Windows 8.x articles, see the archive ]

Gets or sets a value that indicates whether text selection is enabled in the TextBlock, either through user action or calling selection-related API.

Conditionally Remove Dataframe Rows with R

Subset is your safest and easiest answer.

subset(dataframe, A==B & E!=0)

Real data example with mtcars

subset(mtcars, cyl==6 & am!=0)

Numbering rows within groups in a data frame

Another dplyr possibility could be:

df %>%
 group_by(cat) %>%
 mutate(num = 1:n())

   cat      val   num
   <fct>  <dbl> <int>
 1 aaa   0.0564     1
 2 aaa   0.258      2
 3 aaa   0.308      3
 4 aaa   0.469      4
 5 aaa   0.552      5
 6 bbb   0.170      1
 7 bbb   0.370      2
 8 bbb   0.484      3
 9 bbb   0.547      4
10 bbb   0.812      5
11 ccc   0.280      1
12 ccc   0.398      2
13 ccc   0.625      3
14 ccc   0.763      4
15 ccc   0.882      5

Getting a 500 Internal Server Error on Laravel 5+ Ubuntu 14.04

A frequent issue when using git:

Laravel's .gitignore ignores the .env file which when missing generates this error

Solved this by manually adding an .env file on the server or uploading it through FTP

How do I disable directory browsing?

Edit/Create an .htaccess file inside /galerias with this:

Options -Indexes

Directory browsing is provided by the mod_autoindex module.

hash keys / values as array

Here are implementations from phpjs.org:

This is not my code, I'm just pointing you to a useful resource.

AngularJS POST Fails: Response for preflight has invalid HTTP status code 404

For a Node.js app, in the server.js file before registering all of my own routes, I put the code below. It sets the headers for all responses. It also ends the response gracefully if it is a pre-flight "OPTIONS" call and immediately sends the pre-flight response back to the client without "nexting" (is that a word?) down through the actual business logic routes. Here is my server.js file. Relevant sections highlighted for Stackoverflow use.

// server.js

// ==================
// BASE SETUP

// import the packages we need
var express    = require('express');
var app        = express();
var bodyParser = require('body-parser');
var morgan     = require('morgan');
var jwt        = require('jsonwebtoken'); // used to create, sign, and verify tokens

// ====================================================
// configure app to use bodyParser()
// this will let us get the data from a POST
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());

// Logger
app.use(morgan('dev'));

// -------------------------------------------------------------
// STACKOVERFLOW -- PAY ATTENTION TO THIS NEXT SECTION !!!!!
// -------------------------------------------------------------

//Set CORS header and intercept "OPTIONS" preflight call from AngularJS
var allowCrossDomain = function(req, res, next) {
    res.header('Access-Control-Allow-Origin', '*');
    res.header('Access-Control-Allow-Methods', 'GET,PUT,POST,DELETE');
    res.header('Access-Control-Allow-Headers', 'Content-Type');
    if (req.method === "OPTIONS") 
        res.send(200);
    else 
        next();
}

// -------------------------------------------------------------
// STACKOVERFLOW -- END OF THIS SECTION, ONE MORE SECTION BELOW
// -------------------------------------------------------------


// =================================================
// ROUTES FOR OUR API

var route1 = require("./routes/route1");
var route2 = require("./routes/route2");
var error404 = require("./routes/error404");


// ======================================================
// REGISTER OUR ROUTES with app

// -------------------------------------------------------------
// STACKOVERFLOW -- PAY ATTENTION TO THIS NEXT SECTION !!!!!
// -------------------------------------------------------------

app.use(allowCrossDomain);

// -------------------------------------------------------------
//  STACKOVERFLOW -- OK THAT IS THE LAST THING.
// -------------------------------------------------------------

app.use("/api/v1/route1/", route1);
app.use("/api/v1/route2/", route2);
app.use('/', error404);

// =================
// START THE SERVER

var port = process.env.PORT || 8080;        // set our port
app.listen(port);
console.log('API Active on port ' + port);

MVC If statement in View

You only need to prefix an if statement with @ if you're not already inside a razor code block.

Edit: You have a couple of things wrong with your code right now.

You're declaring nmb, but never actually doing anything with the value. So you need figure out what that's supposed to actually be doing. In order to fix your code, you need to make a couple of tiny changes:

@if (ViewBag.Articles != null)
{
    int nmb = 0;
    foreach (var item in ViewBag.Articles)
    {
        if (nmb % 3 == 0)
        {
            @:<div class="row"> 
        }

        <a href="@Url.Action("Article", "Programming", new { id = item.id })">
            <div class="tasks">
                <div class="col-md-4">
                    <div class="task important">
                        <h4>@item.Title</h4>
                        <div class="tmeta">
                            <i class="icon-calendar"></i>
                                @item.DateAdded - Pregleda:@item.Click
                            <i class="icon-pushpin"></i> Authorrr
                        </div>
                    </div>
                </div>
            </div>
        </a>
        if (nmb % 3 == 0)
        {
            @:</div>
        }
    }
}

The important part here is the @:. It's a short-hand of <text></text>, which is used to force the razor engine to render text.

One other thing, the HTML standard specifies that a tags can only contain inline elements, and right now, you're putting a div, which is a block-level element, inside an a.

How to use a table type in a SELECT FROM statement?

Thanks for all help at this issue. I'll post here my solution:

Package Header

CREATE OR REPLACE PACKAGE X IS
  TYPE exch_row IS RECORD(
    currency_cd VARCHAR2(9),
    exch_rt_eur NUMBER,
    exch_rt_usd NUMBER);
  TYPE exch_tbl IS TABLE OF X.exch_row;

  FUNCTION GetExchangeRate RETURN X.exch_tbl PIPELINED;
END X;

Package Body

CREATE OR REPLACE PACKAGE BODY X IS
  FUNCTION GetExchangeRate RETURN X.exch_tbl
    PIPELINED AS
    exch_rt_usd NUMBER := 1.0; --todo
    rw exch_row;
  BEGIN

    FOR rw IN (SELECT c.currency_cd AS currency_cd, e.exch_rt AS exch_rt_eur, (e.exch_rt / exch_rt_usd) AS exch_rt_usd
                 FROM exch e, currency c
                WHERE c.currency_key = e.currency_key
                  ) LOOP
      PIPE ROW(rw);
    END LOOP;
  END;


  PROCEDURE DoIt IS
  BEGIN
    DECLARE
      CURSOR c0 IS
        SELECT i.DOC,
               i.doc_currency,
               i.net_value,
               i.net_value / rt.exch_rt_usd AS net_value_in_usd,
               i.net_value / rt.exch_rt_eur AS net_value_in_euro,
          FROM item i, (SELECT * FROM TABLE(X.GetExchangeRate())) rt
         WHERE i.doc_currency = rt.currency_cd;

      TYPE c0_type IS TABLE OF c0%ROWTYPE;

      items c0_type;
    BEGIN
      OPEN c0;

      LOOP
        FETCH c0 BULK COLLECT
          INTO items LIMIT batchsize;

        EXIT WHEN items.COUNT = 0;
        FORALL i IN items.FIRST .. items.LAST SAVE EXCEPTIONS
          INSERT INTO detail_items VALUES items (i);

      END LOOP;

      CLOSE c0;

      COMMIT;

    EXCEPTION
      WHEN OTHERS THEN
        RAISE;
    END;
  END;

END X;

Please review.

Get restaurants near my location

Is this what you are looking for?

https://maps.googleapis.com/maps/api/place/search/xml?location=49.260691,-123.137784&radius=500&sensor=false&key=*PlacesAPIKey*&types=restaurant

types is optional

append new row to old csv file python

If the file exists and contains data, then it is possible to generate the fieldname parameter for csv.DictWriter automatically:

# read header automatically
with open(myFile, "r") as f:
    reader = csv.reader(f)
    for header in reader:
        break

# add row to CSV file
with open(myFile, "a", newline='') as f:
    writer = csv.DictWriter(f, fieldnames=header)
    writer.writerow(myDict)

ClassCastException, casting Integer to Double

Well the code you've shown doesn't actually include adding any Integers to the ArrayList - but if you do know that you've got integers, you can use:

sum = (double) ((Integer) marks.get(i)).intValue();

That will convert it to an int, which can then be converted to double. You can't just cast directly between the boxed classes.

Note that if you can possibly use generics for your ArrayList, your code will be clearer.

docker-compose up for only certain containers

You usually don't want to do this. With Docker Compose you define services that compose your app. npm and manage.py are just management commands. You don't need a container for them. If you need to, say create your database tables with manage.py, all you have to do is:

docker-compose run client python manage.py create_db

Think of it as the one-off dynos Heroku uses.

If you really need to treat these management commands as separate containers (and also use Docker Compose for these), you could create a separate .yml file and start Docker Compose with the following command:

docker-compose up -f my_custom_docker_compose.yml

How to make a <div> appear in front of regular text/tables

You can use the stacking index of the div to make it appear on top of anything else. Make it a larger value that other elements and it well be on top of others.

use z-index property. See Specifying the stack level: the 'z-index' property and

Elaborate description of Stacking Contexts

Something like

#divOnTop { z-index: 1000; }

<div id="divOnTop">I am on top</div>

What you have to look out for will be IE6. In IE 6 some elements like <select> will be placed on top of an element with z-index value higher than the <select>. You can have a workaround for this by placing an <iframe> behind the div.

See this Internet Explorer z-index bug?

Babel command not found

For those using Yarn as their package manager instead of npm:

yarn global add babel-cli

syntax error, unexpected T_VARIABLE

There is no semicolon at the end of that instruction causing the error.

EDIT

Like RiverC pointed out, there is no semicolon at the end of the previous line!

require ("scripts/connect.php") 

EDIT

It seems you have no-semicolons whatsoever.

http://php.net/manual/en/language.basic-syntax.instruction-separation.php

As in C or Perl, PHP requires instructions to be terminated with a semicolon at the end of each statement.

SELECT only rows that contain only alphanumeric characters in MySQL

Your statement matches any string that contains a letter or digit anywhere, even if it contains other non-alphanumeric characters. Try this:

SELECT * FROM table WHERE column REGEXP '^[A-Za-z0-9]+$';

^ and $ require the entire string to match rather than just any portion of it, and + looks for 1 or more alphanumberic characters.

You could also use a named character class if you prefer:

SELECT * FROM table WHERE column REGEXP '^[[:alnum:]]+$';

How to get JSON objects value if its name contains dots?

If json object key/name contains dot......! like

var myJson = {"my.name":"vikas","my.age":27}

Than you can access like

myJson["my.name"]
myJson["my.age"]

How do I update an entity using spring-data-jpa?

Since the answer by @axtavt focuses on JPA not spring-data-jpa

To update an entity by querying then saving is not efficient because it requires two queries and possibly the query can be quite expensive since it may join other tables and load any collections that have fetchType=FetchType.EAGER

Spring-data-jpa supports update operation.
You have to define the method in Repository interface.and annotated it with @Query and @Modifying.

@Modifying
@Query("update User u set u.firstname = ?1, u.lastname = ?2 where u.id = ?3")
void setUserInfoById(String firstname, String lastname, Integer userId);

@Query is for defining custom query and @Modifying is for telling spring-data-jpa that this query is an update operation and it requires executeUpdate() not executeQuery().

You can specify other return types:
int - the number of records being updated.
boolean - true if there is a record being updated. Otherwise, false.


Note: Run this code in a Transaction.

How to take keyboard input in JavaScript?

Since event.keyCode is deprecated, I found the event.key useful in javascript. Below is an example for getting the names of the keyboard keys pressed (using an input element). They are given as a KeyboardEvent key text property:

_x000D_
_x000D_
function setMyKeyDownListener() {_x000D_
    window.addEventListener(_x000D_
      "keydown",_x000D_
      function(event) {MyFunction(event.key)}_x000D_
    )_x000D_
}_x000D_
_x000D_
function MyFunction (the_Key) {_x000D_
    alert("Key pressed is: "+the_Key);_x000D_
}
_x000D_
html { font-size: 4vw; background-color: green; color: white; padding: 1em; }
_x000D_
<body onload="setMyKeyDownListener()">_x000D_
    <div>_x000D_
        <input id="MyInputId">_x000D_
    </div>_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

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).

Run PHP function on html button click

If you want to make a server request you should use AJAX, so you can send your desired parameters to the server and it can run whatever php you want with these parameters.

Example with pure javascript:

<input type="text" id="name" value="..."/>
<input type="text" id="location" value="..."/>
<input type="button" onclick="ajaxFunction();" value="Submit" />
<div id="ajaxDiv"></div>
<script type="text/javascript">    
    function ajaxFunction(){
        var ajaxRequest;  // The variable that makes Ajax possible!

        try{
            // Opera 8.0+, Firefox, Safari
            ajaxRequest = new XMLHttpRequest();
        } catch (e){
            // Internet Explorer Browsers
            try{
                ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (e) {
                try{
                    ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
                } catch (e){
                    // Something went wrong
                    alert("Your browser broke!");
                    return false;
                }
            }
        }
        // Create a function that will receive data sent from the server
        ajaxRequest.onreadystatechange = function(){
            if(ajaxRequest.readyState == 4){
                var ajaxDisplay = document.getElementById('ajaxDiv');
                ajaxDisplay.innerHTML = ajaxRequest.responseText;
            }
        }
        var name = document.getElementById('name').value;
        var location = document.getElementById('location').value;
        var queryString = "?name=" + name + "&location=" + location;
        ajaxRequest.open("POST", "some.php" + queryString, true);
        ajaxRequest.send(null); 
    }
</script>

Example with jQuery Ajax: http://api.jquery.com/jQuery.ajax/

$.ajax({
  type: "POST",
  url: "some.php",
  data: { name: "John", location: "Boston" }
}).done(function( msg ) {
  alert( "Data Saved: " + msg );
});

You can have one file with functions called for example functions.php

functions.php

<?php
  myFunction($Name, $Location) {
      // etc...
  }
  myFunction2() {
  }
  // ... many functions
?>

some.php

<?php include("functions.php");    
$Name = $_POST['name'];
$Location = $_POST['location'];

myFunction($Name, $Location);

// make what you want with these variables...?>

Position a CSS background image x pixels from the right?

Solution for negative values. Adjust the padding-right to move the image.

<div style='overflow:hidden;'>

    <div style='width:100% background:url(images.jpg) top right; padding-right:50px;'>

    </div>

</div>

Generate 'n' unique random numbers within a range

You could add to a set until you reach n:

setOfNumbers = set()
while len(setOfNumbers) < n:
    setOfNumbers.add(random.randint(numLow, numHigh))

Be careful of having a smaller range than will fit in n. It will loop forever, unable to find new numbers to insert up to n

How can I explicitly free memory in Python?

According to Python Official Documentation, you can force the Garbage Collector to release unreferenced memory with gc.collect(). Example:

import gc
gc.collect()

how to display toolbox on the left side of window of Visual Studio Express for windows phone 7 development?

I had this problem with Blend for Visual Studio 2015. The Toolbox would just not appear anymore. This turns out to be because Blend is not Visual Studio!

(You can edit your code in Blend and build and run it... It certainly seems like Visual Studio, but it isn't. I'm not sure what the purpose of Blend is...)

You can tell you are in Blend if the task bar icon has big "B" in it. To switch from Blend to Visual Studio, go to View-> Edit in Visual Studio.... It will open up another application that looks just like Blend, except the Solution Explorer is on the right instead of the left, and now you have a toolbox...

Is the server running on host "localhost" (::1) and accepting TCP/IP connections on port 5432?

The postgresql server might be down and the solution might be as simple as running:

sudo service postgresql start

which fixed the issue for me.

Checking Value of Radio Button Group via JavaScript?

To get the value you would do this:

document.getElementById("genderf").value;

But to check, whether the radio button is checked or selected:

document.getElementById("genderf").checked;

The type is defined in an assembly that is not referenced, how to find the cause?

I had this issue on a newly created solution that used existing projects. For some reason, one project could not "see" one other project, even though it had the same reference as every other project, and the referenced project was also building. I suspect that it was failing to detect something having to do with multiple target frameworks, because it was building in one framework but not the other.

Cleaning and rebuilding didn't work, and restarting VS didn't work.

What ended up working was opening a "Developer Command Prompt for VS 2019" and then issuing a msbuild MySolution.sln command. This completed successfully, and afterwards VS started building successfully also.

How to send an object from one Android Activity to another using Intents?

in your class model (Object) implement Serializable, for Example:

public class MensajesProveedor implements Serializable {

    private int idProveedor;


    public MensajesProveedor() {
    }

    public int getIdProveedor() {
        return idProveedor;
    }

    public void setIdProveedor(int idProveedor) {
        this.idProveedor = idProveedor;
    }


}

and your first Activity

MensajeProveedor mp = new MensajeProveedor();
Intent i = new Intent(getApplicationContext(), NewActivity.class);
                i.putExtra("mensajes",mp);
                startActivity(i);

and your second Activity (NewActivity)

        MensajesProveedor  mensajes = (MensajesProveedor)getIntent().getExtras().getSerializable("mensajes");

good luck!!

#1071 - Specified key was too long; max key length is 1000 bytes

run this query before creating or altering table.

SET @@global.innodb_large_prefix = 1;

this will set max key length to 3072 bytes

How to convert datetime to integer in python

I think I have a shortcut for that:

# Importing datetime.
from datetime import datetime

# Creating a datetime object so we can test.
a = datetime.now()

# Converting a to string in the desired format (YYYYMMDD) using strftime
# and then to int.
a = int(a.strftime('%Y%m%d'))

Rails 3 migrations: Adding reference column?

Please note that you will most likely need an index on that column too.

class AddUserReferenceToTester < ActiveRecord::Migration
  def change
    add_column :testers, :user_id, :integer
    add_index  :testers, :user_id
  end
end

ERROR: Cannot open source file " "

You need to check your project settings, under C++, check include directories and make sure it points to where GameEngine.h resides, the other issue could be that GameEngine.h is not in your source file folder or in any include directory and resides in a different folder relative to your project folder. For instance you have 2 projects ProjectA and ProjectB, if you are including GameEngine.h in some source/header file in ProjectA then to include it properly, assuming that ProjectB is in the same parent folder do this:

include "../ProjectB/GameEngine.h"

This is if you have a structure like this:

Root\ProjectA

Root\ProjectB <- GameEngine.h actually lives here

base_url() function not working in codeigniter

In order to use base_url(), you must first have the URL Helper loaded. This can be done either in application/config/autoload.php (on or around line 67):

$autoload['helper'] = array('url');

Or, manually:

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

Once it's loaded, be sure to keep in mind that base_url() doesn't implicitly print or echo out anything, rather it returns the value to be printed:

echo base_url();

Remember also that the value returned is the site's base url as provided in the config file. CodeIgniter will accomodate an empty value in the config file as well:

If this (base_url) is not set then CodeIgniter will guess the protocol, domain and path to your installation.

application/config/config.php, line 13

How can I tell gcc not to inline a function?

static __attribute__ ((noinline))  void foo()
{

}

This is what worked for me.

Python Linked List

Expanding Nick Stinemates's answer

class Node(object):
    def __init__(self):
        self.data = None
        self.next = None

class LinkedList:
    def __init__(self):
        self.head = None

    def prepend_node(self, data):
        new_node = Node()
        new_node.data = data
        new_node.next = self.head
        self.head = new_node

    def append_node(self, data):
        new_node = Node()
        new_node.data = data
        current = self.head
        while current.next:
            current = current.next
        current.next = new_node

    def reverse(self):
        """ In-place reversal, modifies exiting list"""
        previous = None
        current_node = self.head

        while current_node:
            temp =  current_node.next
            current_node.next = previous
            previous = current_node
            current_node = temp
        self.head = previous

    def search(self, data):
        current_node = self.head
        try:
            while current_node.data != data:
                current_node = current_node.next
            return True
        except:
            return False

    def display(self):
        if self.head is None:
            print("Linked list is empty")
        else:
            current_node = self.head
            while current_node:
                print(current_node.data)
                current_node = current_node.next

    def list_length(self):
        list_length = 0
        current_node = self.head
        while current_node:
            list_length += 1
            current_node = current_node.next
        return list_length


def main():
    linked_list = LinkedList()

    linked_list.prepend_node(1)
    linked_list.prepend_node(2)
    linked_list.prepend_node(3)
    linked_list.append_node(24)
    linked_list.append_node(25)
    linked_list.display()
    linked_list.reverse()
    linked_list.display()
    print(linked_list.search(1))
    linked_list.reverse()
    linked_list.display()
    print("Lenght of singly linked list is: " + str(linked_list.list_length()))


if __name__ == "__main__":
    main()

Maven: add a folder or jar file into current classpath

From docs and example it is not clear that classpath manipulation is not allowed.

<configuration>
 <compilerArgs>
  <arg>classpath=${basedir}/lib/bad.jar</arg>
 </compilerArgs>
</configuration>

But see Java docs (also https://www.cis.upenn.edu/~bcpierce/courses/629/jdkdocs/tooldocs/solaris/javac.html)

-classpath path Specifies the path javac uses to look up classes needed to run javac or being referenced by other classes you are compiling. Overrides the default or the CLASSPATH environment variable if it is set.

Maybe it is possible to get current classpath and extend it,
see in maven, how output the classpath being used?

    <properties>
      <cpfile>cp.txt</cpfile>
    </properties>

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-dependency-plugin</artifactId>
    <version>2.9</version>
    <executions>
      <execution>
        <id>build-classpath</id>
        <phase>generate-sources</phase>
        <goals>
          <goal>build-classpath</goal>
        </goals>
        <configuration>
          <outputFile>${cpfile}</outputFile>
        </configuration>
      </execution>
    </executions>
  </plugin>

Read file (Read a file into a Maven property)

<plugin>
  <groupId>org.codehaus.gmaven</groupId>
  <artifactId>gmaven-plugin</artifactId>
  <version>1.4</version>
  <executions>
    <execution>
      <phase>generate-resources</phase>
      <goals>
        <goal>execute</goal>
      </goals>
      <configuration>
        <source>
          def file = new File(project.properties.cpfile)
          project.properties.cp = file.getText()
        </source>
      </configuration>
    </execution>
  </executions>
</plugin>

and finally

  <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>3.6.1</version>
    <configuration>
      <compilerArgs>
         <arg>classpath=${cp}:${basedir}/lib/bad.jar</arg>
      </compilerArgs>
    </configuration>
   </plugin>

Image.open() cannot identify image file - Python?

I had a same issue.

from PIL import Image

instead of

import Image

fixed the issue

Change Text Color of Selected Option in a Select Box

You could do it like this.

jsFiddle

JS

var select = document.getElementById('mySelect');
select.onchange = function () {
    select.className = this.options[this.selectedIndex].className;
}

CSS

.redText {
    background-color:#F00;
}
.greenText {
    background-color:#0F0;
}
.blueText {
    background-color:#00F;
}

You could use option { background-color: #FFF; } if you want the list to be white.

HTML

<select id="mySelect" class="greenText">
    <option class="greenText" value="apple" >Apple</option>
    <option class="redText"   value="banana" >Banana</option>
    <option class="blueText" value="grape" >Grape</option>
</select>

Since this is a select it doesn't really make sense to use .yellowText as none selected if that's what you were getting at as something must be selected.

C# Checking if button was clicked

These helped me a lot: I wanted to save values from my gridview, and it was reloading my gridview /overriding my new values, as i have IsPostBack inside my PageLoad.

if (HttpContext.Current.Request["MYCLICKEDBUTTONID"] == null)
{
   //Do not reload the gridview.

}
else
{
   reload my gridview.
}

SOURCE: http://bytes.com/topic/asp-net/answers/312809-please-help-how-identify-button-clicked

How do I conditionally add attributes to React components?

This should work, since your state will change after the Ajax call, and the parent component will re-render.

render : function () {
    var item;
    if (this.state.isRequired) {
        item = <MyOwnInput attribute={'whatever'} />
    } else {
        item = <MyOwnInput />
    }
    return (
        <div>
            {item}
        </div>
    );
}

How do you add an array to another array in Ruby and not end up with a multi-dimensional result?

The cleanest approach is to use the Array#concat method; it will not create a new array (unlike Array#+ which will do the same thing but create a new array).

Straight from the docs (http://www.ruby-doc.org/core-1.9.3/Array.html#method-i-concat):

concat(other_ary)

Appends the elements of other_ary to self.

So

[1,2].concat([3,4])  #=> [1,2,3,4]  

Array#concat will not flatten a multidimensional array if it is passed in as an argument. You'll need to handle that separately:

arr= [3,[4,5]]
arr= arr.flatten   #=> [3,4,5]
[1,2].concat(arr)  #=> [1,2,3,4,5]

Lastly, you can use our corelib gem (https://github.com/corlewsolutions/corelib) which adds useful helpers to the Ruby core classes. In particular we have an Array#add_all method which will automatically flatten multidimensional arrays before executing the concat.

Angular 2 - Setting selected value on dropdown list

Angular 2 simple dropdown selected value

It may help someone as I need to only show selected value, don't need to declare something in component and etc.

If your status is coming from the database then you can show selected value this way.

<div class="form-group">
    <label for="status">Status</label>
    <select class="form-control" name="status" [(ngModel)]="category.status">
       <option [value]="1" [selected]="category.status ==1">Active</option>
       <option [value]="0" [selected]="category.status ==0">In Active</option>
    </select>
</div>

How to add action listener that listens to multiple buttons

The problem is that button1 is a local variable. You could do it by just change the way you add the actionListener.

button.addActionListener(new ActionListener() {  
            public void actionPerformed(ActionEvent e)
            {
                //button is pressed
                System.out.println("You clicked the button");
            }});

Or you make button1 a global variable.

adding 1 day to a DATETIME format value

You can use

$now = new DateTime();
$date = $now->modify('+1 day')->format('Y-m-d H:i:s');

Activating Anaconda Environment in VsCode

Unfortunately, this does not work on macOS. Despite the fact that I have export CONDA_DEFAULT_ENV='$HOME/anaconda3/envs/dev' in my .zshrc and "python.pythonPath": "${env.CONDA_DEFAULT_ENV}/bin/python", in my VSCode prefs, the built-in terminal does not use that environment's Python, even if I have started VSCode from the command line where that variable is set.

Generate a UUID on iOS from Swift

For Swift 3, many Foundation types have dropped the 'NS' prefix, so you'd access it by UUID().uuidString.

MySQL date format DD/MM/YYYY select query?

SELECT DATE_FORMAT(somedate, "%d/%m/%Y") AS formatted_date
..........
ORDER BY formatted_date DESC

How to hide column of DataGridView when using custom DataSource?

In some cases, it might be a bad idea to first add the column to the DataGridView and then hide it.

I for example have a class that has an NHibernate proxy for an Image property for company logos. If I accessed that property (e.g. by calling its ToString method to show that in a DataGridView), it would download the image from the SQL server. If I had a list of Company objects and used that as the dataSource of the DataGridView like that, then (I suspect) it would download ALL the logos BEFORE I could hide the column.

To prevent this, I used the custom attribute

 [System.ComponentModel.Browsable(false)]

on the image property, so that the DataGridView ignores the property (doesn't create the column and doesn't call the ToString methods).

 public class Company
 {
     ...
     [System.ComponentModel.Browsable(false)]
     virtual public MyImageClass Logo { get; set;}

How to convert string representation of list to a list?

The eval is dangerous - you shouldn't execute user input.

If you have 2.6 or newer, use ast instead of eval:

>>> import ast
>>> ast.literal_eval('["A","B" ,"C" ," D"]')
["A", "B", "C", " D"]

Once you have that, strip the strings.

If you're on an older version of Python, you can get very close to what you want with a simple regular expression:

>>> x='[  "A",  " B", "C","D "]'
>>> re.findall(r'"\s*([^"]*?)\s*"', x)
['A', 'B', 'C', 'D']

This isn't as good as the ast solution, for example it doesn't correctly handle escaped quotes in strings. But it's simple, doesn't involve a dangerous eval, and might be good enough for your purpose if you're on an older Python without ast.

How can I add (simple) tracing in C#?

I followed around five different answers as well as all the blog posts in the previous answers and still had problems. I was trying to add a listener to some existing code that was tracing using the TraceSource.TraceEvent(TraceEventType, Int32, String) method where the TraceSource object was initialised with a string making it a 'named source'.

For me the issue was not creating a valid combination of source and switch elements to target this source. Here is an example that will log to a file called tracelog.txt. For the following code:

TraceSource source = new TraceSource("sourceName");
source.TraceEvent(TraceEventType.Verbose, 1, "Trace message");

I successfully managed to log with the following diagnostics configuration:

<system.diagnostics>
    <sources>
        <source name="sourceName" switchName="switchName">
            <listeners>
                <add
                    name="textWriterTraceListener"
                    type="System.Diagnostics.TextWriterTraceListener"
                    initializeData="tracelog.txt" />
            </listeners>
        </source>
    </sources>

    <switches>
        <add name="switchName" value="Verbose" />
    </switches>
</system.diagnostics>

How to get array keys in Javascript?

widthRange.map(function(_, i) { return i });

or

widthRange.map((_, i) => i);

How to decode a QR-code image in (preferably pure) Python?

There is a library called BoofCV which claims to better than ZBar and other libraries.
Here are the steps to use that (any OS).

Pre-requisites:

  • Ensure JDK 14+ is installed and set in $PATH
  • pip install pyboof

Class to decode:

import os
import numpy as np
import pyboof as pb

pb.init_memmap() #Optional

class QR_Extractor:
    # Src: github.com/lessthanoptimal/PyBoof/blob/master/examples/qrcode_detect.py
    def __init__(self):
        self.detector = pb.FactoryFiducial(np.uint8).qrcode()
    
    def extract(self, img_path):
        if not os.path.isfile(img_path):
            print('File not found:', img_path)
            return None
        image = pb.load_single_band(img_path, np.uint8)
        self.detector.detect(image)
        qr_codes = []
        for qr in self.detector.detections:
            qr_codes.append({
                'text': qr.message,
                'points': qr.bounds.convert_tuple()
            })
        return qr_codes

Usage:

qr_scanner = QR_Extractor()
output = qr_scanner.extract('Your-Image.jpg')
print(output)

Tested and works on Python 3.8 (Windows & Ubuntu)

Swift Beta performance: sorting arrays

As of Xcode 7 you can turn on Fast, Whole Module Optimization. This should increase your performance immediately.

enter image description here

How to get day of the month?

It is simplified a lot in version Java 8. I have given some util methods below.

To get the day of the month in the format of int for the given day, month, and year.

    public static int findDay(final int month, final int day, final int year) {
        // System.out.println(LocalDate.of(year, month, day).getDayOfMonth());
        return LocalDate.of(year, month, day).getDayOfMonth();
    }

To get current day of the month in the format of int.

    public static int findDay(final int month, final int day, final int year) {
        // System.out.println(LocalDate.now(ZoneId.of("Asia/Kolkata")).getDayOfMonth());
        return LocalDate.now(ZoneId.of("Asia/Kolkata")).getDayOfMonth();
    }

To get the day of the week in the format of String for the given day, month, and year.

    public static String findDay(final int month, final int day, final int year) {
        // System.out.println(LocalDate.of(year, month, day).getDayOfWeek());
        return LocalDate.of(year, month, day).getDayOfWeek().toString();
    }

To get current day of the week in the format of String.

    public static String findDay(final int month, final int day, final int year) {
        // System.out.println(LocalDate.now(ZoneId.of("Asia/Kolkata"))..getDayOfWeek());
        return LocalDate.now(ZoneId.of("Asia/Kolkata")).getDayOfWeek().toString();
    }

Open a file with Notepad in C#

System.Diagnostics.Process.Start( "notepad.exe", "text.txt");

ps1 cannot be loaded because running scripts is disabled on this system

If you are using visual studio code:

  1. Open terminal
  2. Run the command: Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy Unrestricted
  3. Then run the command protractor conf.js

This is related to protractor test script execution related and I faced the same issue and it was resolved like this.

How to use background thread in swift?

Dan Beaulieu's answer in swift5 (also working since swift 3.0.1).

Swift 5.0.1

extension DispatchQueue {

    static func background(delay: Double = 0.0, background: (()->Void)? = nil, completion: (() -> Void)? = nil) {
        DispatchQueue.global(qos: .background).async {
            background?()
            if let completion = completion {
                DispatchQueue.main.asyncAfter(deadline: .now() + delay, execute: {
                    completion()
                })
            }
        }
    }

}

Usage

DispatchQueue.background(delay: 3.0, background: {
    // do something in background
}, completion: {
    // when background job finishes, wait 3 seconds and do something in main thread
})

DispatchQueue.background(background: {
    // do something in background
}, completion:{
    // when background job finished, do something in main thread
})

DispatchQueue.background(delay: 3.0, completion:{
    // do something in main thread after 3 seconds
})

How to obfuscate Python code effectively?

Try this python obfuscator:

pyob.oxyry.com pyob.oxyry.c

__all__ = ['foo']

a = 'a'
_b = 'b'

def foo():
    print(a)

def bar():
    print(_b)

def _baz():
    print(a + _b)

foo()
bar()
_baz()

will translated to

__all__ =['foo']#line:1
OO00OO0OO0O00O0OO ='a'#line:3
_O00OO0000OO0O0O0O ='b'#line:4
def foo ():#line:6
    print (OO00OO0OO0O00O0OO )#line:7
def O0000000OOOO00OO0 ():#line:9
    print (_O00OO0000OO0O0O0O )#line:10
def _OOO00000O000O0OOO ():#line:12
    print (OO00OO0OO0O00O0OO +_O00OO0000OO0O0O0O )#line:13
foo ()#line:15
O0000000OOOO00OO0 ()#line:16
_OOO00000O000O0OOO ()#line:17

How can I find out a file's MIME type (Content-Type)?

one of the other tool (besides file) you can use is xdg-mime

eg xdg-mime query filetype <file>

if you have yum,

yum install xdg-utils.noarch

An example comparison of xdg-mime and file on a Subrip(subtitles) file

$ xdg-mime query filetype subtitles.srt
application/x-subrip

$ file --mime-type subtitles.srt
subtitles.srt: text/plain

in the above file only show it as plain text.

Tool to compare directories (Windows 7)

The tool that richardtz suggests is excellent.

Another one that is amazing and comes with a 30 day free trial is Araxis Merge. This one does a 3 way merge and is much more feature complete than winmerge, but it is a commercial product.

You might also like to check out Scott Hanselman's developer tool list, which mentions a couple more in addition to winmerge

Java String to Date object of the format "yyyy-mm-dd HH:mm:ss"

For future reference:

 yyyy => 4 digit year
 MM   => 2 digit month (you must type MM in ALL CAPS)
 dd   => 2 digit "day of the month"

 HH   => 2-digit "hour in day" (0 to 23)
 mm   => 2-digit minute (you must type mm in lowercase)
 ss   => 2-digit seconds
 SSS  => milliseconds

So "yyyy-MM-dd HH:mm:ss" returns "2018-01-05 09:49:32"

But "MMM dd, yyyy hh:mm a" returns "Jan 05, 2018 09:49 am"

The so-called examples at https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html show only output. They do not tell you what formats to use!

How to uninstall/upgrade Angular CLI?

 $ npm uninstall -g angular-cli 
 $ npm cache clean 
 $ npm install -g angular-cli

Counting the number of non-NaN elements in a numpy ndarray in Python

np.count_nonzero(~np.isnan(data))

~ inverts the boolean matrix returned from np.isnan.

np.count_nonzero counts values that is not 0\false. .sum should give the same result. But maybe more clearly to use count_nonzero

Testing speed:

In [23]: data = np.random.random((10000,10000))

In [24]: data[[np.random.random_integers(0,10000, 100)],:][:, [np.random.random_integers(0,99, 100)]] = np.nan

In [25]: %timeit data.size - np.count_nonzero(np.isnan(data))
1 loops, best of 3: 309 ms per loop

In [26]: %timeit np.count_nonzero(~np.isnan(data))
1 loops, best of 3: 345 ms per loop

In [27]: %timeit data.size - np.isnan(data).sum()
1 loops, best of 3: 339 ms per loop

data.size - np.count_nonzero(np.isnan(data)) seems to barely be the fastest here. other data might give different relative speed results.

Collections.sort with multiple fields

Sorting with multiple fields in Java8

package com.java8.chapter1;

import java.util.Arrays;
import java.util.Comparator;
import java.util.List;
import static java.util.Comparator.*;



 public class Example1 {

    public static void main(String[] args) {
        List<Employee> empList = getEmpList();


        // Before Java 8 
        empList.sort(new Comparator<Employee>() {

            @Override
            public int compare(Employee o1, Employee o2) {
                int res = o1.getDesignation().compareTo(o2.getDesignation());
                if (res == 0) {
                    return o1.getSalary() > o2.getSalary() ? 1 : o1.getSalary() < o2.getSalary() ? -1 : 0;
                } else {
                    return res;
                }

            }
        });
        for (Employee emp : empList) {
            System.out.println(emp);
        }
        System.out.println("---------------------------------------------------------------------------");

        // In Java 8

        empList.sort(comparing(Employee::getDesignation).thenComparing(Employee::getSalary));
        empList.stream().forEach(System.out::println);

    }
    private static List<Employee> getEmpList() {
        return Arrays.asList(new Employee("Lakshman A", "Consultent", 450000),
                new Employee("Chaitra S", "Developer", 250000), new Employee("Manoj PVN", "Developer", 250000),
                new Employee("Ramesh R", "Developer", 280000), new Employee("Suresh S", "Developer", 270000),
                new Employee("Jaishree", "Opearations HR", 350000));
    }
}

class Employee {
    private String fullName;
    private String designation;
    private double salary;

    public Employee(String fullName, String designation, double salary) {
        super();
        this.fullName = fullName;
        this.designation = designation;
        this.salary = salary;
    }

    public String getFullName() {
        return fullName;
    }

    public String getDesignation() {
        return designation;
    }

    public double getSalary() {
        return salary;
    }

    @Override
    public String toString() {
        return "Employee [fullName=" + fullName + ", designation=" + designation + ", salary=" + salary + "]";
    }

}

How can I create a progress bar in Excel VBA?

You can add a Form and name it as Form1, add a Frame to it as Frame1 as well as Label1 too. Set Frame1 width to 200, Back Color to Blue. Place the code in the module and check if it helps.

    Sub Main()
    Dim i As Integer
    Dim response
    Form1.Show vbModeless
    Form1.Frame1.Width = 0
    For i = 10 To 10000
        With Form1
            .Label1.Caption = Round(i / 100, 0) & "%"
            .Frame1.Width = Round(i / 100, 0) * 2
             DoEvents
        End With
    Next i

    Application.Wait Now + 0.0000075

    Unload Form1

    response = MsgBox("100% Done", vbOKOnly)

    End Sub

If you want to display on the Status Bar then you can use other way that's simpler:

   Sub Main()
   Dim i As Integer
   Dim response
   For i = 10 To 10000
        Application.StatusBar = Round(i / 100, 0) & "%"
   Next i

   Application.Wait Now + 0.0000075

   response = MsgBox("100% Done", vbOKOnly)

   End Sub

Disable sorting on last column when using jQuery DataTables

for disable sorting on any column in datatable use the following

aoColumnDefs: [{ "aTargets": [ 0 ], "bSortable": false}],

it means "aTargets": [ 0 ] is the column id starting from 0

so in your case it becomes:

 $(".tableSort").dataTable({
        aaSorting: [[0, 'asc']],
        aoColumnDefs: [
            { "aTargets": [ -1 ], "bSortable": false},
        ]
    });

Is there a way to use SVG as content in a pseudo element :before or :after

You can add the SVG as background-image of an empty :after or :before.

Here you go:

.anchor:before {
  display: block;
  content: ' ';
  background-image: url('../images/anchor.svg');
  background-size: 28px 28px;
  height: 28px;
  width: 28px;
}

Conditionally formatting cells if their value equals any value of another column

I was looking into this and loved the approach from peege using a for loop! (because I'm learning VBA at the moment)

However, if we are trying to match "any" value of another column, how about using nested loops like the following?

Sub MatchAndColor()

Dim lastRow As Long
Dim sheetName As String


sheetName = "Sheet1"            'Insert your sheet name here
lastRow = Sheets(sheetName).Range("A" & Rows.Count).End(xlUp).Row

For lRowA = 1 To lastRow         'Loop through all rows
    For lRowB = 1 To lastRow
        If Sheets(sheetName).Cells(lRowA, "A") = Sheets(sheetName).Cells(lRowB, "B") Then

        Sheets(sheetName).Cells(lRowA, "A").Interior.ColorIndex = 3  'Set Color to RED
    End If

Next lRowB
Next lRowA

End Sub

Spring Security redirect to previous page after successful login

You can use a Custom SuccessHandler extending SimpleUrlAuthenticationSuccessHandler for redirecting users to different URLs when login according to their assigned roles.

CustomSuccessHandler class provides custom redirect functionality:

package com.mycompany.uomrmsweb.configuration;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.web.DefaultRedirectStrategy;
import org.springframework.security.web.RedirectStrategy;
import org.springframework.security.web.authentication.SimpleUrlAuthenticationSuccessHandler;
import org.springframework.stereotype.Component;

@Component
public class CustomSuccessHandler extends SimpleUrlAuthenticationSuccessHandler{

    private RedirectStrategy redirectStrategy = new DefaultRedirectStrategy();

    @Override
    protected void handle(HttpServletRequest request, HttpServletResponse response, Authentication authentication) throws IOException {
        String targetUrl = determineTargetUrl(authentication);

        if (response.isCommitted()) {
            System.out.println("Can't redirect");
            return;
        }

        redirectStrategy.sendRedirect(request, response, targetUrl);
    }

    protected String determineTargetUrl(Authentication authentication) {
        String url="";

        Collection<? extends GrantedAuthority> authorities =  authentication.getAuthorities();

        List<String> roles = new ArrayList<String>();

        for (GrantedAuthority a : authorities) {
            roles.add(a.getAuthority());
        }

        if (isStaff(roles)) {
            url = "/staff";
        } else if (isAdmin(roles)) {
            url = "/admin";
        } else if (isStudent(roles)) {
            url = "/student";
        }else if (isUser(roles)) {
            url = "/home";
        } else {
            url="/Access_Denied";
        }

        return url;
    }

    public void setRedirectStrategy(RedirectStrategy redirectStrategy) {
        this.redirectStrategy = redirectStrategy;
    }
    protected RedirectStrategy getRedirectStrategy() {
        return redirectStrategy;
    }

    private boolean isUser(List<String> roles) {
        if (roles.contains("ROLE_USER")) {
            return true;
        }
        return false;
    }

    private boolean isStudent(List<String> roles) {
        if (roles.contains("ROLE_Student")) {
            return true;
        }
        return false;
    }

    private boolean isAdmin(List<String> roles) {
        if (roles.contains("ROLE_SystemAdmin") || roles.contains("ROLE_ExaminationsStaff")) {
            return true;
        }
        return false;
    }

    private boolean isStaff(List<String> roles) {
        if (roles.contains("ROLE_AcademicStaff") || roles.contains("ROLE_UniversityAdmin")) {
            return true;
        }
        return false;
    }
}

Extending Spring SimpleUrlAuthenticationSuccessHandler class and overriding handle() method which simply invokes a redirect using configured RedirectStrategy [default in this case] with the URL returned by the user defined determineTargetUrl() method. This method extracts the Roles of currently logged in user from Authentication object and then construct appropriate URL based on there roles. Finally RedirectStrategy , which is responsible for all redirections within Spring Security framework , redirects the request to specified URL.

Registering CustomSuccessHandler using SecurityConfiguration class:

package com.mycompany.uomrmsweb.configuration;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
import org.springframework.security.core.userdetails.UserDetailsService;

@Configuration
@EnableWebSecurity
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {

    @Autowired
    @Qualifier("customUserDetailsService")
    UserDetailsService userDetailsService;

    @Autowired
    CustomSuccessHandler customSuccessHandler;

    @Autowired
    public void configureGlobalSecurity(AuthenticationManagerBuilder auth) throws Exception {
            auth.userDetailsService(userDetailsService);
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests()
        .antMatchers("/", "/home").access("hasRole('USER')")
        .antMatchers("/admin/**").access("hasRole('SystemAdmin') or hasRole('ExaminationsStaff')")
        .antMatchers("/staff/**").access("hasRole('AcademicStaff') or hasRole('UniversityAdmin')")
        .antMatchers("/student/**").access("hasRole('Student')")  
                    .and().formLogin().loginPage("/login").successHandler(customSuccessHandler)
        .usernameParameter("username").passwordParameter("password")
        .and().csrf()
        .and().exceptionHandling().accessDeniedPage("/Access_Denied");
    }
}

successHandler is the class responsible for eventual redirection based on any custom logic, which in this case will be to redirect the user [to student/admin/staff ] based on his role [USER/Student/SystemAdmin/UniversityAdmin/ExaminationsStaff/AcademicStaff].

How to get a list of column names

$<?
$db = sqlite_open('mysqlitedb');
$cols = sqlite_fetch_column_types('form name'$db, SQLITE_ASSOC);
foreach ($cols as $column => $type) {
  echo "Column: $column  Type: $type\n";
}

Java equivalent to #region in C#

No equivalent in the language... Based on IDEs...

For example in netbeans:

NetBeans/Creator supports this syntax:

// <editor-fold defaultstate="collapsed" desc="Your Fold Comment">
...
// </editor-fold>

http://forums.java.net/jive/thread.jspa?threadID=1311

Formatting a number with exactly two decimals in JavaScript

This is an old topic but still top-ranked Google results and the solutions offered share the same floating point decimals issue. Here is the (very generic) function I use, thanks to MDN:

function round(value, exp) {
  if (typeof exp === 'undefined' || +exp === 0)
    return Math.round(value);

  value = +value;
  exp = +exp;

  if (isNaN(value) || !(typeof exp === 'number' && exp % 1 === 0))
    return NaN;

  // Shift
  value = value.toString().split('e');
  value = Math.round(+(value[0] + 'e' + (value[1] ? (+value[1] + exp) : exp)));

  // Shift back
  value = value.toString().split('e');
  return +(value[0] + 'e' + (value[1] ? (+value[1] - exp) : -exp));
}

As we can see, we don't get these issues:

round(1.275, 2);   // Returns 1.28
round(1.27499, 2); // Returns 1.27

This genericity also provides some cool stuff:

round(1234.5678, -2);   // Returns 1200
round(1.2345678e+2, 2); // Returns 123.46
round("123.45");        // Returns 123

Now, to answer the OP's question, one has to type:

round(10.8034, 2).toFixed(2); // Returns "10.80"
round(10.8, 2).toFixed(2);    // Returns "10.80"

Or, for a more concise, less generic function:

function round2Fixed(value) {
  value = +value;

  if (isNaN(value))
    return NaN;

  // Shift
  value = value.toString().split('e');
  value = Math.round(+(value[0] + 'e' + (value[1] ? (+value[1] + 2) : 2)));

  // Shift back
  value = value.toString().split('e');
  return (+(value[0] + 'e' + (value[1] ? (+value[1] - 2) : -2))).toFixed(2);
}

You can call it with:

round2Fixed(10.8034); // Returns "10.80"
round2Fixed(10.8);    // Returns "10.80"

Various examples and tests (thanks to @t-j-crowder!):

_x000D_
_x000D_
function round(value, exp) {_x000D_
  if (typeof exp === 'undefined' || +exp === 0)_x000D_
    return Math.round(value);_x000D_
_x000D_
  value = +value;_x000D_
  exp = +exp;_x000D_
_x000D_
  if (isNaN(value) || !(typeof exp === 'number' && exp % 1 === 0))_x000D_
    return NaN;_x000D_
_x000D_
  // Shift_x000D_
  value = value.toString().split('e');_x000D_
  value = Math.round(+(value[0] + 'e' + (value[1] ? (+value[1] + exp) : exp)));_x000D_
_x000D_
  // Shift back_x000D_
  value = value.toString().split('e');_x000D_
  return +(value[0] + 'e' + (value[1] ? (+value[1] - exp) : -exp));_x000D_
}_x000D_
function naive(value, exp) {_x000D_
  if (!exp) {_x000D_
    return Math.round(value);_x000D_
  }_x000D_
  var pow = Math.pow(10, exp);_x000D_
  return Math.round(value * pow) / pow;_x000D_
}_x000D_
function test(val, places) {_x000D_
  subtest(val, places);_x000D_
  val = typeof val === "string" ? "-" + val : -val;_x000D_
  subtest(val, places);_x000D_
}_x000D_
function subtest(val, places) {_x000D_
  var placesOrZero = places || 0;_x000D_
  var naiveResult = naive(val, places);_x000D_
  var roundResult = round(val, places);_x000D_
  if (placesOrZero >= 0) {_x000D_
    naiveResult = naiveResult.toFixed(placesOrZero);_x000D_
    roundResult = roundResult.toFixed(placesOrZero);_x000D_
  } else {_x000D_
    naiveResult = naiveResult.toString();_x000D_
    roundResult = roundResult.toString();_x000D_
  }_x000D_
  $("<tr>")_x000D_
    .append($("<td>").text(JSON.stringify(val)))_x000D_
    .append($("<td>").text(placesOrZero))_x000D_
    .append($("<td>").text(naiveResult))_x000D_
    .append($("<td>").text(roundResult))_x000D_
    .appendTo("#results");_x000D_
}_x000D_
test(0.565, 2);_x000D_
test(0.575, 2);_x000D_
test(0.585, 2);_x000D_
test(1.275, 2);_x000D_
test(1.27499, 2);_x000D_
test(1234.5678, -2);_x000D_
test(1.2345678e+2, 2);_x000D_
test("123.45");_x000D_
test(10.8034, 2);_x000D_
test(10.8, 2);_x000D_
test(1.005, 2);_x000D_
test(1.0005, 2);
_x000D_
table {_x000D_
  border-collapse: collapse;_x000D_
}_x000D_
table, td, th {_x000D_
  border: 1px solid #ddd;_x000D_
}_x000D_
td, th {_x000D_
  padding: 4px;_x000D_
}_x000D_
th {_x000D_
  font-weight: normal;_x000D_
  font-family: sans-serif;_x000D_
}_x000D_
td {_x000D_
  font-family: monospace;_x000D_
}
_x000D_
<table>_x000D_
  <thead>_x000D_
    <tr>_x000D_
      <th>Input</th>_x000D_
      <th>Places</th>_x000D_
      <th>Naive</th>_x000D_
      <th>Thorough</th>_x000D_
    </tr>_x000D_
  </thead>_x000D_
  <tbody id="results">_x000D_
  </tbody>_x000D_
</table>_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

How can I convert a string to a number in Perl?

In comparisons it makes a difference if a scalar is a number of a string. And it is not always decidable. I can report a case where perl retrieved a float in "scientific" notation and used that same a few lines below in a comparison:

use strict;
....
next unless $line =~ /and your result is:\s*(.*)/;
my $val = $1;
if ($val < 0.001) {
   print "this is small\n";
}

And here $val was not interpreted as numeric for e.g. "2e-77" retrieved from $line. Adding 0 (or 0.0 for good ole C programmers) helped.

How to submit http form using C#

I needed to have a button handler that created a form post to another application within the client's browser. I landed on this question but didn't see an answer that suited my scenario. This is what I came up with:

      protected void Button1_Click(object sender, EventArgs e)
        {

            var formPostText = @"<html><body><div>
<form method=""POST"" action=""OtherLogin.aspx"" name=""frm2Post"">
  <input type=""hidden"" name=""field1"" value=""" + TextBox1.Text + @""" /> 
  <input type=""hidden"" name=""field2"" value=""" + TextBox2.Text + @""" /> 
</form></div><script type=""text/javascript"">document.frm2Post.submit();</script></body></html>
";
            Response.Write(formPostText);
        }

Getting java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory exception

Check whether the jars are imported properly. I imported them using build path. But it didn't recognise the jar in WAR/lib folder. Later, I copied the same jar to war/lib folder. It works fine now. You can refresh / clean your project.

Soft hyphen in HTML (<wbr> vs. &shy;)

I use &shy;, inserted manually where necessary.

I always find it a pity that people don’t use techniques because there is some—maybe old or strange—browser around which doesn’t handle them the way they were specified. I found that &shy; is working properly in both recent Internet Explorer and Firefox browsers, that should be enough. You may include a browser check telling people to use something mature or continue at their own risk if they come around with some strange browser.

Syllabification isn’t that easy and I cannot recommend leaving it to some Javascript. It’s a language specific topic and may need to be carefully revised by the deskman if you don’t want it to turn your text irritating. Some languages, such as German, form compound words and are likely to lead to decomposition problems. E.g. Spargelder (germ. saved money, pl.) may, by syllabification rules, be wrapped in two places (Spar-gel-der). However, wrapping it in the second position, turns the first part to show up as Spargel- (germ. asparagus), activating a completely misleading concept in the head of the reader and therefore shoud be avoided.

And what about the string Wachstube? It could either mean ‘guardroom’ (Wach-stu-be) or ‘tube of wax’ (Wachs-tu-be). You may probably find other examples in other languages as well. You should aim to provide an environment in which the deskman can be supported in creating a well-syllabified text, proof-reading every critical word.

Jenkins: Is there any way to cleanup Jenkins workspace?

Assuming the question is about cleaning the workspace of the current job, you can run:

test -n "$WORKSPACE" && rm -rf "$WORKSPACE"/*

How to grant permission to users for a directory using command line in Windows?

  1. navigate to top level directory you want to set permissions to with explorer
  2. type cmd in the address bar of your explorer window
  3. enter icacls . /grant John:(OI)(CI)F /T where John is the username
  4. profit

Just adding this because it seemed supremely easy this way and others may profit - all credit goes to Calin Darie.

Android Respond To URL in Intent

I did it! Using <intent-filter>. Put the following into your manifest file:

<intent-filter>
  <action android:name="android.intent.action.VIEW" />
  <category android:name="android.intent.category.DEFAULT" />
  <category android:name="android.intent.category.BROWSABLE" />
  <data android:host="www.youtube.com" android:scheme="http" />
</intent-filter>

This works perfectly!

Is there a way to check which CSS styles are being used or not used on a web page?

Take a look at UnCSS. It helps in creating a CSS file of used CSS.

How to run shell script on host from docker container?

Write a simple server python server listening on a port (say 8080), bind the port -p 8080:8080 with the container, make a HTTP request to localhost:8080 to ask the python server running shell scripts with popen, run a curl or writing code to make a HTTP request curl -d '{"foo":"bar"}' localhost:8080

#!/usr/bin/python
from BaseHTTPServer import BaseHTTPRequestHandler,HTTPServer
import subprocess
import json

PORT_NUMBER = 8080

# This class will handles any incoming request from
# the browser 
class myHandler(BaseHTTPRequestHandler):
        def do_POST(self):
                content_len = int(self.headers.getheader('content-length'))
                post_body = self.rfile.read(content_len)
                self.send_response(200)
                self.end_headers()
                data = json.loads(post_body)

                # Use the post data
                cmd = "your shell cmd"
                p = subprocess.Popen(cmd, stdout=subprocess.PIPE, shell=True)
                p_status = p.wait()
                (output, err) = p.communicate()
                print "Command output : ", output
                print "Command exit status/return code : ", p_status

                self.wfile.write(cmd + "\n")
                return
try:
        # Create a web server and define the handler to manage the
        # incoming request
        server = HTTPServer(('', PORT_NUMBER), myHandler)
        print 'Started httpserver on port ' , PORT_NUMBER

        # Wait forever for incoming http requests
        server.serve_forever()

except KeyboardInterrupt:
        print '^C received, shutting down the web server'
        server.socket.close()

How to dump raw RTSP stream to file?

With this command I had poor image quality

ffmpeg -i rtsp://192.168.XXX.XXX:554/live.sdp -vcodec copy -acodec copy -f mp4 -y MyVideoFFmpeg.mp4

With this, almost without delay, I got good image quality.

ffmpeg -i rtsp://192.168.XXX.XXX:554/live.sdp -b 900k -vcodec copy -r 60 -y MyVdeoFFmpeg.avi

CKEditor, Image Upload (filebrowserUploadUrl)

For those have same problem in Grails ckeditor plugin Give

filebrowserUploadUrl:'/YourAppName/ck/ofm'

to invoke the function that handles image uploade.if you want use your own customized function you can give that file path.

Python function pointer

def f(a,b):
    return a+b

xx = 'f'
print eval('%s(%s,%s)'%(xx,2,3))

OUTPUT

 5

Private Variables and Methods in Python

Double underscore. That mangles the name. The variable can still be accessed, but it's generally a bad idea to do so.

Use single underscores for semi-private (tells python developers "only change this if you absolutely must") and doubles for fully private.

Getting the HTTP Referrer in ASP.NET

I'm using .Net Core 2 mvc, this one work for me ( to get the previews page) :

HttpContext.Request.Headers["Referer"];

Force file download with php using header()

Here is a snippet from me in testing... obviously passing via get to the script may not be the best... should post or just send an id and grab guid from db... anyhow.. this worked. I take the URL and convert it to a path.

// Initialize a file URL to the variable
$file = $_GET['url'];
$file = str_replace(Polepluginforrvms_Plugin::$install_url, $DOC_ROOT.'/pole-permitter/', $file );

$quoted = sprintf('"%s"', addcslashes(basename($file), '"\\'));
$size   = filesize($file);

header( "Content-type: application/octet-stream" );
header( "Content-Disposition: attachment; filename={$quoted}" );
header( "Content-length: " . $size );
header( "Pragma: no-cache" );
header( "Expires: 0" );
readfile( "{$file}" );

Append value to empty vector in R?

FWIW: analogous to python's append():

b <- 1
b <- c(b, 2)

How do I display a text file content in CMD?

Using a single PowerShell command to retrieve the file ending:

powershell -nologo "& "Get-Content -Wait c:\logFile.log -Tail 10"

It applies to PowerShell 3.0 and newer.

Another option is to create a file called TAIL.CMD with this code:

powershell -nologo "& "Get-Content -Wait %1 -Tail %2"

Change image source with JavaScript

Hi i tried to integrate with your code.

Can you have a look at this?

Thanks M.S

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
_x000D_
<!--TODO: need to integrate this code into the project to change images added 05/21/2016:-->_x000D_
_x000D_
<script type="text/javascript">_x000D_
    function changeImage(a) {_x000D_
        document.getElementById("img").src=a;_x000D_
    }_x000D_
</script>_x000D_
_x000D_
_x000D_
 _x000D_
<title> Fluid Selection </title>_x000D_
<!-- css -->_x000D_
 <link rel="stylesheet" href="bootstrap-3/css/bootstrap.min.css">_x000D_
 <link rel="stylesheet" href="css/main.css">_x000D_
<!-- end css -->_x000D_
<!-- Java script files -->_x000D_
<!-- Date.js date os javascript helper -->_x000D_
    <script src="js/date.js"> </script>_x000D_
_x000D_
<!-- jQuery (necessary for Bootstrap's JavaScript plugins) -->_x000D_
 <script src="js/jquery-2.1.1.min.js"></script>_x000D_
_x000D_
<!-- Include all compiled plugins (below), or include individual files as needed -->_x000D_
 <script src="bootstrap-3/js/bootstrap.min.js"> </script>_x000D_
 <script src="js/library.js"> </script>_x000D_
 <script src="js/sfds.js"> </script>_x000D_
 <script src="js/main.js"> </script>_x000D_
_x000D_
<!-- End Java script files -->_x000D_
_x000D_
<!--added on 05/28/2016-->_x000D_
_x000D_
<style>_x000D_
/* The Modal (background) */_x000D_
.modal {_x000D_
    display: none; /* Hidden by default */_x000D_
    position: fixed; /* Stay in place */_x000D_
    z-index:40001; /* High z-index to ensure it appears above all content */ _x000D_
    padding-top: 100px; /* Location of the box */_x000D_
    left: 0;_x000D_
    top: 0;_x000D_
    width: 100%; /* Full width */_x000D_
    height: 100%; /* Full height */_x000D_
    overflow: auto; /* Enable scroll if needed */_x000D_
   _x000D_
    background-color: rgba(0,0,0,0.9); /* Black w/ opacity */_x000D_
}_x000D_
_x000D_
/* Modal Content */_x000D_
.modal-content {_x000D_
    position: relative;_x000D_
    background-color: #fefefe;_x000D_
    margin: auto;_x000D_
    padding: 0;_x000D_
    border: 1px solid #888;_x000D_
    width: 40%;_x000D_
    box-shadow: 0 4px 8px 0 rgba(0,0,0,0.2),0 6px 20px 0 rgba(0,0,0,0.19);_x000D_
    -webkit-animation-name: animatetop;_x000D_
    -webkit-animation-duration: 0.4s;_x000D_
    animation-name: animatetop;_x000D_
    animation-duration: 0.4s_x000D_
 opacity:.5; /* Sets opacity so it's partly transparent */ -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=50)"; _x000D_
 /* IE     _x000D_
 transparency */ filter:alpha(opacity=50); /* More IE transparency */ z-index:40001; } _x000D_
}_x000D_
_x000D_
/* Add Animation */_x000D_
@-webkit-keyframes animatetop {_x000D_
    from {top:-300px; opacity:0} _x000D_
    to {top:0; opacity:1}_x000D_
}_x000D_
_x000D_
@keyframes animatetop {_x000D_
    from {top:-300px; opacity:0}_x000D_
    to {top:0; opacity:1}_x000D_
}_x000D_
_x000D_
/* The Close Button */_x000D_
.close {_x000D_
    _x000D_
}_x000D_
_x000D_
.close:hover,_x000D_
.close:focus {_x000D_
    color: #000;_x000D_
    text-decoration: none;_x000D_
    cursor:pointer;_x000D_
}_x000D_
_x000D_
/* The Close Button */_x000D_
.close2 {_x000D_
    _x000D_
}_x000D_
_x000D_
_x000D_
.close2:focus {_x000D_
    color: #000;_x000D_
    text-decoration: none;_x000D_
    cursor:pointer;_x000D_
}_x000D_
_x000D_
.modal-header {_x000D_
 color: #000;_x000D_
    padding: 2px 16px;_x000D_
 }_x000D_
_x000D_
.modal-body {padding: 2px 16px;}_x000D_
 _x000D_
 _x000D_
}_x000D_
_x000D_
.modal-footer {_x000D_
    padding: 2px 16px;_x000D_
    background-color: #000099;_x000D_
    color: white;_x000D_
}_x000D_
_x000D_
_x000D_
</style>_x000D_
_x000D_
<script>_x000D_
 $(document).ready(function() {_x000D_
 _x000D_
 _x000D_
  $("#water").click(function(event){_x000D_
   var $this= $(this);_x000D_
   if($this.hasClass('clicked')){_x000D_
    $this.removeClass('clicked');_x000D_
    SFDS.setFluidType(0);_x000D_
    $this.find('h3').text('Select the H20 Fluid Type');_x000D_
    }else{_x000D_
     SFDS.setFluidType(1);_x000D_
     $this.addClass('clicked');_x000D_
     $this.find('h3').text('H20 Selected');_x000D_
_x000D_
   }_x000D_
  });_x000D_
  _x000D_
  $("#saline").click(function(event){_x000D_
   var $this= $(this);_x000D_
   if($this.hasClass('clicked')){_x000D_
    $this.removeClass('clicked');_x000D_
    SFDS.setFluidType(0);_x000D_
    $this.find('h3').text('Select the NaCL Fluid Type');_x000D_
    }else{_x000D_
     SFDS.setFluidType(1);_x000D_
     $this.addClass('clicked');_x000D_
     $this.find('h3').text('NaCL Selected');_x000D_
     _x000D_
  _x000D_
  _x000D_
   }_x000D_
  });_x000D_
  _x000D_
 });_x000D_
</script>_x000D_
</head>_x000D_
<body>_x000D_
<div class="container-fluid">_x000D_
 <header>_x000D_
  <div class="row">_x000D_
   <div class="col-xs-6">_x000D_
    <div id="date"><span class="date_time"></span></div>_x000D_
   </div>_x000D_
   <div class="col-xs-6">_x000D_
    <div id="time" class="text-right"><span class="date_time"></span></div>_x000D_
   </div>_x000D_
  </div>_x000D_
 </header>_x000D_
_x000D_
 <div class="row">_x000D_
  <div class="col-md-offset-1 col-sm-3 col-xs-8 col-xs-offset-2 col-sm-offset-0">_x000D_
   <div id="fluid" class="main_button center-block">_x000D_
    <div class="large_circle_button, main_img"> _x000D_
     <h2>Select<br>Fluid</h2>_x000D_
     <img class="center-block large_button_image" src="images/dropwater.png" alt=""/> _x000D_
    </div>_x000D_
    <h1></h1>_x000D_
   </div>_x000D_
  </div>_x000D_
  <div class=" col-md-6 col-sm-offset-1 col-sm-8 col-xs-12">_x000D_
   <div class="row">_x000D_
    <div class="col-xs-12">_x000D_
     <div id="water" class="large_rectangle_button">_x000D_
      <div class="label_wrapper">_x000D_
       <h3>Sterile<br>Water</h3>_x000D_
      </div>_x000D_
      <div id="thumb_img" class="image_wrapper">_x000D_
       <img src="images/dropsterilewater.png" alt="Sterile Water" class="sterile_water_image" onclick='changeImage("images/dropsterilewater.png");'>_x000D_
      </div>_x000D_
      <img src="images/checkmark.png" class="button_checkmark" width="96" height="88">_x000D_
     </div>_x000D_
    </div>_x000D_
    <div class="col-xs-12">_x000D_
     <div id="saline" class="large_rectangle_button">_x000D_
      <div class="label_wrapper">_x000D_
       <h3>Sterile<br>0.9% NaCL</h3>_x000D_
      </div>_x000D_
      <div class="image_wrapper">_x000D_
       <img src="images/cansterilesaline.png" alt= "Sterile Saline" class="sterile_salt_image" onclick='changeImage("images/imagecansterilesaline.png");'>_x000D_
      </div>_x000D_
      <img src="images/checkmark.png" class="button_checkmark" width="96" height="88">_x000D_
_x000D_
     </div>_x000D_
    </div>_x000D_
    <div class="col-xs-12">_x000D_
     <div class="small_rectangle_button">_x000D_
      _x000D_
      <!-- Trigger/Open The Modal -->_x000D_
      <div id="myBtn" class="label_wrapper">_x000D_
       <h3>Change<br>Cartridge</h3>_x000D_
      </div>_x000D_
      <div class="image_wrapper">_x000D_
       <img src="images/changecartridge.png" alt="" class="change_cartrige_image" />_x000D_
      </div>_x000D_
     </div>_x000D_
    </div>_x000D_
    _x000D_
     <!-- The Modal -->_x000D_
     <div id="myModal" class="modal">_x000D_
_x000D_
       <!-- Modal content -->_x000D_
       <div class="modal-content">_x000D_
      <div class="modal-header">_x000D_
        <span class="close"><img src="images/x-icon.png"></span>_x000D_
        <h2>Change Cartridge Instructions</h2>_x000D_
      </div>_x000D_
      <div class="modal-body">_x000D_
        <h4>Lorem ipsum dolor sit amet, dicant nonumes volutpat cu eum, in nulla molestie vim, nec probo option iracundia ut. Tale inermis scripserit ne cum, his no errem minimum commune, usu accumsan omnesque in. Eu has nihil dolor debitis, ad nobis impedit per. Dicat mnesarchum quo at, debet abhorreant consectetuer sea te, postea adversarium et eos. At alii dicit his, liber tantas suscipit sea in, id pri erat probatus. Vel nostro periculis dissentiet te, ut ubique noster vix. Id honestatis disputationi vel, ne vix assum constituam.</h4>                                                   _x000D_
                           <a href="#"><img src="images/video-icon.png" alt="click here for video"> </a>_x000D_
                           <a href="#close2" title="Close" class="close2"><img src="images/cancel-icon.png" alt="Cancel"></a>_x000D_
_x000D_
                          _x000D_
      </div>_x000D_
      <div class="modal-footer">_x000D_
        <h4></h4>_x000D_
      </div>_x000D_
       </div>_x000D_
_x000D_
     </div>_x000D_
     _x000D_
     <!--for comparison-->_x000D_
_x000D_
_x000D_
     _x000D_
_x000D_
     _x000D_
     <script>_x000D_
     // Get the modal_x000D_
     var modal = document.getElementById('myModal');_x000D_
_x000D_
     // Get the button that opens the modal_x000D_
     var btn = document.getElementById("myBtn");_x000D_
_x000D_
     // Get the <span> element that closes the modal_x000D_
     var span = document.getElementsByClassName("close")[0];_x000D_
     _x000D_
_x000D_
     // When the user clicks the button, open the modal _x000D_
     btn.onclick = function() {_x000D_
      modal.style.display = "block";_x000D_
     }_x000D_
_x000D_
     // When the user clicks on <span> (x), close the modal_x000D_
     span.onclick = function() {_x000D_
      modal.style.display = "none";_x000D_
     }_x000D_
_x000D_
     // When the user clicks anywhere outside of the modal, close it_x000D_
     window.onclick = function(event) {_x000D_
      if (event.target == modal) {_x000D_
       modal.style.display = "none";_x000D_
      }_x000D_
      _x000D_
      _x000D_
     }_x000D_
     </script>_x000D_
                    _x000D_
_x000D_
    _x000D_
    _x000D_
    _x000D_
    _x000D_
    _x000D_
   </div>_x000D_
  </div>_x000D_
 </div>_x000D_
</div>_x000D_
<footer class="footer navbar-fixed-bottom">_x000D_
 <div class="container-fluid">_x000D_
  <div class="row cols-bottom">_x000D_
   <div class="col-sm-3">_x000D_
    <a href="main.html">_x000D_
    <div class="small_circle_button">     _x000D_
     <img src="images/buttonback.png" alt="back to home" class="settings"/> <!--  width="49" height="48" -->_x000D_
    </div>_x000D_
   </div></a><div class=" col-sm-6">_x000D_
    <div id="stop_button" >_x000D_
     <img src="images/stop.png" alt="stop" class="center-block stop_button" /> <!-- width="140" height="128" -->_x000D_
    </div>_x000D_
     _x000D_
   </div><div class="col-sm-3">_x000D_
    <div id="parker" class="pull-right">_x000D_
     <img src="images/parkerlogo.png" alt="parkerlogo" /> <!-- width="131" height="65" -->_x000D_
    </div>_x000D_
   </div>_x000D_
  </div>_x000D_
 </div>_x000D_
</footer>_x000D_
_x000D_
_x000D_
</body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

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

You have 2 different versions of JSON.NET library in your solution. To solve this you should upgrade them to latest version. Follow these steps:

1-Open solution explorer 2-Right Click on solution name 3-Select Manage Nuget Packages for Solution 4-Select Updates from menu 5-Update JSON.NET package

This will resolve your issue.

link: Could not load file or assembly 'Newtonsoft.Json, Version=7.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed' or one of its dependencies

Set a thin border using .css() in javascript

After a few futile hours battling with a 'SyntaxError: missing : after property id' message I can now expand on this topic:

border-width is a valid css property but it is not included in the jQuery css oject definition, so .css({border-width: '2px'}) will cause an error, but it's quite happy with .css({'border-width': '2px'}), presumably property names in quotes are just passed on as received.

phpMyAdmin ERROR: mysqli_real_connect(): (HY000/1045): Access denied for user 'pma'@'localhost' (using password: NO)

I solved the problem by adding the line skip-grant-tables to the my.ini:

# The MySQL server
[mysqld]
skip-grant-tables
port= 3306
...

Under XAMPP Control Panel > Section "MySQL" > Config > my.ini

Why does Java have an "unreachable statement" compiler error?

One of the goals of compilers is to rule out classes of errors. Some unreachable code is there by accident, it's nice that javac rules out that class of error at compile time.

For every rule that catches erroneous code, someone will want the compiler to accept it because they know what they're doing. That's the penalty of compiler checking, and getting the balance right is one of the tricker points of language design. Even with the strictest checking there's still an infinite number of programs that can be written, so things can't be that bad.

What is the max size of localStorage values?

I wrote this simple code that is testing localStorage size in bytes.

https://github.com/gkucmierz/Test-of-localStorage-limits-quota

const check = bytes => {
  try {
    localStorage.clear();
    localStorage.setItem('a', '0'.repeat(bytes));
    localStorage.clear();
    return true;
  } catch(e) {
    localStorage.clear();
    return false;
  }
};

Github pages:

https://gkucmierz.github.io/Test-of-localStorage-limits-quota/

I have the same results on desktop chrome, opera, firefox, brave and mobile chrome which is ~5Mbytes

enter image description here

And half smaller result in safari ~2Mbytes

enter image description here

What are database constraints?

  1. UNIQUE constraint (of which a PRIMARY KEY constraint is a variant). Checks that all values of a given field are unique across the table. This is X-axis constraint (records)

  2. CHECK constraint (of which a NOT NULL constraint is a variant). Checks that a certain condition holds for the expression over the fields of the same record. This is Y-axis constraint (fields)

  3. FOREIGN KEY constraint. Checks that a field's value is found among the values of a field in another table. This is Z-axis constraint (tables).

Can the :not() pseudo-class have multiple arguments?

If you install the "cssnext" Post CSS plugin, then you can safely start using the syntax that you want to use right now.

Using cssnext will turn this:

input:not([type="radio"], [type="checkbox"]) {
  /* css here */
}

Into this:

input:not([type="radio"]):not([type="checkbox"]) {
  /* css here */
}

https://cssnext.github.io/features/#not-pseudo-class

How do you pass a function as a parameter in C?

Pass address of a function as parameter to another function as shown below

#include <stdio.h>

void print();
void execute(void());

int main()
{
    execute(print); // sends address of print
    return 0;
}

void print()
{
    printf("Hello!");
}

void execute(void f()) // receive address of print
{
    f();
}

Also we can pass function as parameter using function pointer

#include <stdio.h>

void print();
void execute(void (*f)());

int main()
{
    execute(&print); // sends address of print
    return 0;
}

void print()
{
    printf("Hello!");
}

void execute(void (*f)()) // receive address of print
{
    f();
}

JPA - Returning an auto generated id after persist()

You could also use GenerationType.TABLE instead of IDENTITY which is only available after the insert.

Is it better to use std::memcpy() or std::copy() in terms to performance?

Always use std::copy because memcpy is limited to only C-style POD structures, and the compiler will likely replace calls to std::copy with memcpy if the targets are in fact POD.

Plus, std::copy can be used with many iterator types, not just pointers. std::copy is more flexible for no performance loss and is the clear winner.

Convert string to title case with JavaScript

There's been some great answers, but, with many people using regex to find the word, but, for some reason, nobody else uses regex to replace the first character. For explanation, I'll provide a long solution and a shorter one.

The long solution (more explanatory). By using regular expression [^\s_\-/]* we can find every word in the sentence. Subsequently, we can use the regular expression . to match to the first character in a word. Using the regular expression version of replace for both of these, we can change the solution like this:

_x000D_
_x000D_
function toUpperCase(str) { return str.toUpperCase(); }_x000D_
function capitalizeWord(word) { return word.replace(/./, toUpperCase); }_x000D_
function capitalize(sentence) { return sentence.toLowerCase().replace(/[^\s_\-/]*/g, capitalizeWord); }_x000D_
_x000D_
console.log(capitalize("hello world")); // Outputs: Hello World
_x000D_
_x000D_
_x000D_

For a single function that does the same thing, we nest the replace calls as follows:

_x000D_
_x000D_
function capitalize(sentence) {_x000D_
  return sentence.toLowerCase().replace(/[^\s_\-/]*/g, function (word) {_x000D_
    return word.replace(/./, function (ch) { return ch.toUpperCase(); } );_x000D_
  } );_x000D_
}_x000D_
_x000D_
console.log(capitalize("hello world")); // Outputs: Hello World
_x000D_
_x000D_
_x000D_

Javascript for "Add to Home Screen" on iPhone?

The only way to add any book marks in MobileSafari (including ones on the home screen) is with the builtin UI, and that Apples does not provide anyway to do this from scripts within a page. In fact, I am pretty sure there is no mechanism for doing this on the desktop version of Safari either.

Border Height on CSS

Just like everyone else said, you can't control border height. But there are workarounds, here's what I do:

table {
  position: relative;
}

table::before { /* ::after works too */
  content: "";
  position: absolute;
  right: 0; /* Change direction for a different side*/
  z-index: 100; 
  width: 3px; /* Thickness */
  height: 10px;
  background: #555; /* Color */
}

You can set height to inherit for the height of the table or calc(inherit - 2px) for a 2px smaller border. Remember, inherit has no effect when the table height isn't set.

Use height: 50% for half a border.

Demo

Having links relative to root?

Use this code "./" as root on the server as it works for me

<a href="./fruits/index.html">Back to Fruits List</a>

but when you are on a local machine use the following code "../" as the root relative path

<a href="../fruits/index.html">Back to Fruits List</a>

Get error message if ModelState.IsValid fails?

Ok Check and Add to Watch:

  1. Do a breakpoint at your ModelState line in your Code
  2. Add your model state to your Watch
  3. Expand ModelState "Values"
  4. Expand Values "Results View"

Now you can see a list of all SubKey with its validation state at end of value.

So search for the Invalid value.

Textarea Auto height

For those of us accomplishing this with Angular JS, I used a directive

HTML:

<textarea elastic ng-model="someProperty"></textarea>

JS:

.directive('elastic', [
    '$timeout',
    function($timeout) {
        return {
            restrict: 'A',
            link: function($scope, element) {
                $scope.initialHeight = $scope.initialHeight || element[0].style.height;
                var resize = function() {
                    element[0].style.height = $scope.initialHeight;
                    element[0].style.height = "" + element[0].scrollHeight + "px";
                };
                element.on("input change", resize);
                $timeout(resize, 0);
            }
        };
    }
]);

$timeout queues an event that will fire after the DOM loads, which is what's necessary to get the right scrollHeight (otherwise you'll get undefined)

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

Well, yes, and no...

I understand that you want your local copies to "override" what's in the remote, but, oh, man, if someone has modified the files in the remote repo in some different way, and you just ignore their changes and try to "force" your own changes without even looking at possible conflicts, well, I weep for you (and your coworkers) ;-)

That said, though, it's really easy to do the "right thing..."

Step 1:

git stash

in your local repo. That will save away your local updates into the stash, then revert your modified files back to their pre-edit state.

Step 2:

git pull

to get any modified versions. Now, hopefully, that won't get any new versions of the files you're worried about. If it doesn't, then the next step will work smoothly. If it does, then you've got some work to do, and you'll be glad you did.

Step 3:

git stash pop

That will merge your modified versions that you stashed away in Step 1 with the versions you just pulled in Step 2. If everything goes smoothly, then you'll be all set!

If, on the other hand, there were real conflicts between what you pulled in Step 2 and your modifications (due to someone else editing in the interim), you'll find out and be told to resolve them. Do it.

Things will work out much better this way - it will probably keep your changes without any real work on your part, while alerting you to serious, serious issues.

HttpWebRequest-The remote server returned an error: (400) Bad Request

What type of authentication do you use? Send the credentials using the properties Ben said before and setup a cookie handler. You already allow redirection, check your webserver if any redirection occurs (NTLM auth does for sure). If there is a redirection you need to store the session which is mostly stored in a session cookie.

What is the difference between Sessions and Cookies in PHP?

A session is a chunk of data maintained at the server that maintains state between HTTP requests. HTTP is fundamentally a stateless protocol; sessions are used to give it statefulness.

A cookie is a snippet of data sent to and returned from clients. Cookies are often used to facilitate sessions since it tells the server which client handled which session. There are other ways to do this (query string magic etc) but cookies are likely most common for this.

how to change the default positioning of modal in bootstrap?

Add the following css to your html and try changing the top, right, bottom, left values.

.modal {
   position: absolute;
   top: 10px;
   right: 100px;
   bottom: 0;
   left: 0;
   z-index: 10040;
   overflow: auto;
   overflow-y: auto;
}

How to set multiple commands in one yaml file with Kubernetes?

If you're willing to use a Volume and a ConfigMap, you can mount ConfigMap data as a script, and then run that script:

---
apiVersion: v1
kind: ConfigMap
metadata:
  name: my-configmap
data:
  entrypoint.sh: |-
    #!/bin/bash
    echo "Do this"

    echo "Do that"
---
apiVersion: v1
kind: Pod
metadata:
  name: my-pod
spec:
  containers:
  - name: my-container
    image: "ubuntu:14.04"
    command:
    - /bin/entrypoint.sh
    volumeMounts:
    - name: configmap-volume
      mountPath: /bin/entrypoint.sh
      readOnly: true
      subPath: entrypoint.sh
  volumes:
  - name: configmap-volume
    configMap:
      defaultMode: 0700
      name: my-configmap

This cleans up your pod spec a little and allows for more complex scripting.

$ kubectl logs my-pod
Do this
Do that

Abstract Class vs Interface in C++

I assume that with interface you mean a C++ class with only pure virtual methods (i.e. without any code), instead with abstract class you mean a C++ class with virtual methods that can be overridden, and some code, but at least one pure virtual method that makes the class not instantiable. e.g.:

class MyInterface
{
public:
  // Empty virtual destructor for proper cleanup
  virtual ~MyInterface() {}

  virtual void Method1() = 0;
  virtual void Method2() = 0;
};


class MyAbstractClass
{
public:
  virtual ~MyAbstractClass();

  virtual void Method1();
  virtual void Method2();
  void Method3();

  virtual void Method4() = 0; // make MyAbstractClass not instantiable
};

In Windows programming, interfaces are fundamental in COM. In fact, a COM component exports only interfaces (i.e. pointers to v-tables, i.e. pointers to set of function pointers). This helps defining an ABI (Application Binary Interface) that makes it possible to e.g. build a COM component in C++ and use it in Visual Basic, or build a COM component in C and use it in C++, or build a COM component with Visual C++ version X and use it with Visual C++ version Y. In other words, with interfaces you have high decoupling between client code and server code.

Moreover, when you want to build DLL's with a C++ object-oriented interface (instead of pure C DLL's), as described in this article, it's better to export interfaces (the "mature approach") instead of C++ classes (this is basically what COM does, but without the burden of COM infrastructure).

I'd use an interface if I want to define a set of rules using which a component can be programmed, without specifying a concrete particular behavior. Classes that implement this interface will provide some concrete behavior themselves.

Instead, I'd use an abstract class when I want to provide some default infrastructure code and behavior, and make it possible to client code to derive from this abstract class, overriding the pure virtual methods with some custom code, and complete this behavior with custom code. Think for example of an infrastructure for an OpenGL application. You can define an abstract class that initializes OpenGL, sets up the window environment, etc. and then you can derive from this class and implement custom code for e.g. the rendering process and handling user input:

// Abstract class for an OpenGL app.
// Creates rendering window, initializes OpenGL; 
// client code must derive from it 
// and implement rendering and user input.
class OpenGLApp
{
public:
  OpenGLApp();
  virtual ~OpenGLApp();
  ...

  // Run the app    
  void Run();


  // <---- This behavior must be implemented by the client ---->

  // Rendering
  virtual void Render() = 0;

  // Handle user input
  // (returns false to quit, true to continue looping)
  virtual bool HandleInput() = 0;

  // <--------------------------------------------------------->


private:
  //
  // Some infrastructure code
  //
  ... 
  void CreateRenderingWindow();
  void CreateOpenGLContext();
  void SwapBuffers();
};


class MyOpenGLDemo : public OpenGLApp
{
public:
  MyOpenGLDemo();
  virtual ~MyOpenGLDemo();

  // Rendering
  virtual void Render();  // implements rendering code

  // Handle user input
  virtual bool HandleInput(); // implements user input handling


  //  ... some other stuff
};

PHPUnit assert that an exception was thrown?

public function testException() {
    try {
        $this->methodThatThrowsException();
        $this->fail("Expected Exception has not been raised.");
    } catch (Exception $ex) {
        $this->assertEquals($ex->getMessage(), "Exception message");
    }

}

WARNING: Can't verify CSRF token authenticity rails

  1. Make sure that you have <%= csrf_meta_tag %> in your layout
  2. Add a beforeSend to include the csrf-token in the ajax request to set the header. This is only required for post requests.

The code to read the csrf-token is available in the rails/jquery-ujs, so imho it is easiest to just use that, as follows:

$.ajax({
  url: url,
  method: 'post',
  beforeSend: $.rails.CSRFProtection,
  data: {
    // ...
  }
})

iPhone SDK on Windows (alternative solutions)

No, you must have an Intel Mac of some sort. I went to Best Buy and got a 24" iMac with 4G RAM for $1499 using their 18 month no interest promotion. I pay a minimum payment of something like $16 a month. As long as I pay the entire thing off within 18 months - no interest. That was the only way I was getting into iPhone development.

Converting XDocument to XmlDocument and vice versa

You could try writing the XDocument to an XmlWriter piped to an XmlReader for an XmlDocument.

If I understand the concepts properly, a direct conversion is not possible (the internal structure is different / simplified with XDocument). But then, I might be wrong...

Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled

In my case i have included jdbc api dependencies in the project so the "Hello World" not printed. After removing the below dependency it works like a charm.

       <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

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

If you have start-stop-daemon

start-stop-daemon --start --quiet -u username -g usergroup --exec command ...

[INSTALL_FAILED_NO_MATCHING_ABIS: Failed to extract native libraries, res=-113]

This is caused by a gradle dependency on some out-of-date thing which causes the error. Remove gradle dependencies until the error stops appearing. For me, it was:

implementation 'org.apache.directory.studio:org.apache.commons.io:2.4'

This line needed to be updated to a newer version such as:

api group: 'commons-io', name: 'commons-io', version: '2.6'

Elegant way to check for missing packages and install them?

You can just use the return value of require:

if(!require(somepackage)){
    install.packages("somepackage")
    library(somepackage)
}

I use library after the install because it will throw an exception if the install wasn't successful or the package can't be loaded for some other reason. You make this more robust and reuseable:

dynamic_require <- function(package){
  if(eval(parse(text=paste("require(",package,")")))) return True

  install.packages(package)
  return eval(parse(text=paste("require(",package,")")))
}

The downside to this method is that you have to pass the package name in quotes, which you don't do for the real require.

How can I do string interpolation in JavaScript?

Since ES6, you can use template literals:

_x000D_
_x000D_
const age = 3_x000D_
console.log(`I'm ${age} years old!`)
_x000D_
_x000D_
_x000D_

P.S. Note the use of backticks: ``.

ERROR 2006 (HY000): MySQL server has gone away

Just in case, to check variables you can use

$> mysqladmin variables -u user -p 

This will display the current variables, in this case max_allowed_packet, and as someone said in another answer you can set it temporarily with

mysql> SET GLOBAL max_allowed_packet=1072731894

In my case the cnf file was not taken into account and I don't know why, so the SET GLOBAL code really helped.

Unix shell script find out which directory the script file resides?

Assuming you're using bash

#!/bin/bash

current_dir=$(pwd)
script_dir=$(dirname "$0")

echo $current_dir
echo $script_dir

This script should print the directory that you're in, and then the directory the script is in. For example, when calling it from / with the script in /home/mez/, it outputs

/
/home/mez

Remember, when assigning variables from the output of a command, wrap the command in $( and ) - or you won't get the desired output.

ASP.NET Web Api: The requested resource does not support http method 'GET'

All above information is correct, I'd also like to point out that the [AcceptVerbs()] annotation exists in both the System.Web.Mvc and System.Web.Http namespaces.

You want to use the System.Web.Http if it's a Web API controller.

How do I dynamically change the content in an iframe using jquery?

var handle = setInterval(changeIframe, 30000);
var sites = ["google.com", "yahoo.com"];
var index = 0;

function changeIframe() {
  $('#frame')[0].src = sites[index++];
  index = index >= sites.length ? 0 : index;
}

How to write to a file, using the logging Python module?

An example of using logging.basicConfig rather than logging.fileHandler()

logging.basicConfig(filename=logname,
                            filemode='a',
                            format='%(asctime)s,%(msecs)d %(name)s %(levelname)s %(message)s',
                            datefmt='%H:%M:%S',
                            level=logging.DEBUG)

logging.info("Running Urban Planning")

self.logger = logging.getLogger('urbanGUI')

In order, the five parts do the following:

  1. set the output file (filename=logname)
  2. set it to append rather than overwrite (filemode='a')
  3. determine the format of the output message (format=...)
  4. determine the format of the output time (datefmt='%H:%M:%S')
  5. and determine the minimum message level it will accept (level=logging.DEBUG).

How to check radio button is checked using JQuery?

This is best practice

$("input[name='radioGroup']:checked").val()

Create directories using make file

make in, and off itself, handles directory targets just the same as file targets. So, it's easy to write rules like this:

outDir/someTarget: Makefile outDir
    touch outDir/someTarget

outDir:
    mkdir -p outDir

The only problem with that is, that the directories timestamp depends on what is done to the files inside. For the rules above, this leads to the following result:

$ make
mkdir -p outDir
touch outDir/someTarget
$ make
touch outDir/someTarget
$ make
touch outDir/someTarget
$ make
touch outDir/someTarget

This is most definitely not what you want. Whenever you touch the file, you also touch the directory. And since the file depends on the directory, the file consequently appears to be out of date, forcing it to be rebuilt.

However, you can easily break this loop by telling make to ignore the timestamp of the directory. This is done by declaring the directory as an order-only prerequsite:

# The pipe symbol tells make that the following prerequisites are order-only
#                           |
#                           v
outDir/someTarget: Makefile | outDir
    touch outDir/someTarget

outDir:
    mkdir -p outDir

This correctly yields:

$ make
mkdir -p outDir
touch outDir/someTarget
$ make
make: 'outDir/someTarget' is up to date.

TL;DR:

Write a rule to create the directory:

$(OUT_DIR):
    mkdir -p $(OUT_DIR)

And have the targets for the stuff inside depend on the directory order-only:

$(OUT_DIR)/someTarget: ... | $(OUT_DIR)

check if a file is open in Python

You could use with open("path") as file: so that it automatically closes, else if it's open in another process you can maybe try as in Tims example you should use except IOError to not ignore any other problem with your code :)

try:
   with open("path", "r") as file: # or just open
       # Code here
except IOError:
   # raise error or print

Android: Tabs at the BOTTOM

Not sure if it will work for all versions of Android (especially those with custom UI stuff), but I was able to remove the gray bar at the bottom by adding

 android:layout_marginBottom="-3dp"

to the TabWidget XML...

How create Date Object with values in java

import java.io.*;
import java.util.*;
import java.util.HashMap;

public class Solution 
{

    public static void main(String[] args)
    {
        HashMap<Integer,String> hm = new HashMap<Integer,String>();
        hm.put(1,"SUNDAY");
        hm.put(2,"MONDAY");
        hm.put(3,"TUESDAY");
        hm.put(4,"WEDNESDAY");
        hm.put(5,"THURSDAY");
        hm.put(6,"FRIDAY");
        hm.put(7,"SATURDAY");
        Scanner in = new Scanner(System.in);
        String month = in.next();
        String day = in.next();
        String year = in.next();

        String format = year + "/" + month + "/" + day;
        Date date = null;
        try
        {
            SimpleDateFormat formatter = new SimpleDateFormat("yyyy/MM/dd");
            date = formatter.parse(format);
        }
        catch(Exception e){
        }
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        int dayOfWeek = c.get(Calendar.DAY_OF_WEEK);
        System.out.println(hm.get(dayOfWeek));
    }
}

Not able to change TextField Border Color

That is not changing due to the default theme set to the screen.

So just change them for the widget you are drawing by wrapping your TextField with new ThemeData()

child: new Theme(
          data: new ThemeData(
            primaryColor: Colors.redAccent,
            primaryColorDark: Colors.red,
          ),
          child: new TextField(
            decoration: new InputDecoration(
                border: new OutlineInputBorder(
                    borderSide: new BorderSide(color: Colors.teal)),
                hintText: 'Tell us about yourself',
                helperText: 'Keep it short, this is just a demo.',
                labelText: 'Life story',
                prefixIcon: const Icon(
                  Icons.person,
                  color: Colors.green,
                ),
                prefixText: ' ',
                suffixText: 'USD',
                suffixStyle: const TextStyle(color: Colors.green)),
          ),
        ));

enter image description here

How to get .app file of a xcode application

You can find the .app file here:

~/Library/Developer/Xcode/DerivedData/{app name}/Build/Products/Deployment/ 

credit for path goes to this answer

SIDENOTE: I had a lot of fun trying to get this into my iPad after that. It worked however. Using Snow Leopard + Xcode 4.2 + iPad with IOS 5.1.1 :) - I used the iPhone configuration utility to get the app into the ipad (you have to add the app, then click on the device, then click "install" behind the app you just added in the "application library" of iphone configuration utility) and had to create a Distribution Provisioning Profile and get the WWDR certificate and finally change the build settings in Xcode after all the certificates were in place. See here

But after much fun I am now looking at my first app on my iPad :) - btw, for getting apps into the app store you need to create a app store Distribution Provisioning Profile, while for ad hoc installs like these you create an ad hoc one. There is a bit more to it, but I think these are the most important and tricky steps. Enjoy.

PS. Just remembered that you also have to set the build type (top left of Xcode) to "iOS device", otherwise it will never sign your application. So the path name above only has limited value: yes, it will have the .app file in it, but no you can't upload it (at least not using the iPhone configuration utility) since it is not code signed - you will get an "Could not copy validate signature" error. So change it to "iOS device" and build (remember to select the right certificates in the build section of Xcode as per the url info above). In that same build section, you can also set the "Installation Build Products Location" to a different path, so that you can determine where the .app (the one that is properly code signed) ends up.

What is this weird colon-member (" : ") syntax in the constructor?

That's constructor initialisation. It is the correct way to initialise members in a class constructor, as it prevents the default constructor being invoked.

Consider these two examples:

// Example 1
Foo(Bar b)
{
   bar = b;
}

// Example 2
Foo(Bar b)
   : bar(b)
{
}

In example 1:

Bar bar;  // default constructor
bar = b;  // assignment

In example 2:

Bar bar(b) // copy constructor

It's all about efficiency.

Can vue-router open a link in a new tab?

This worked for me-

let routeData = this.$router.resolve(
{
  path: '/resources/c-m-communities', 
  query: {'dataParameter': 'parameterValue'}
});
window.open(routeData.href, '_blank');

I modified @Rafael_Andrs_Cspedes_Basterio answer

Python: PIP install path, what is the correct location for this and other addons?

Modules go in site-packages and executables go in your system's executable path. For your environment, this path is /usr/local/bin/.

To avoid having to deal with this, simply use easy_install, distribute or pip. These tools know which files need to go where.

nginx: [emerg] "server" directive is not allowed here

Example valid nginx.conf for reverse proxy; In case someone is stuck like me. where 10.x.x.x is the server where you are running the nginx proxy server and to which you are connecting to with the browser, and 10.y.y.y is where your real web server is running

events {
  worker_connections  4096;  ## Default: 1024
}
http {
 server {
   listen 80;
   listen [::]:80;

   server_name 10.x.x.x;
 
   location / {
       proxy_pass http://10.y.y.y:80/;
       proxy_set_header Host $host;
   }
 }
}

Here is the snippet if you want to do SSL pass through. That is if 10.y.y.y is running a HTTPS webserver. Here 10.x.x.x, or where the nignx runs is listening to port 443, and all traffic to 443 is directed to your target web server

events {
  worker_connections  4096;  ## Default: 1024
}

stream {
  server {
    listen     443;
    proxy_pass 10.y.y.y:443;
  }
}

and you can serve it up in docker too

 docker run --name nginx-container --rm --net=host   -v /home/core/nginx/nginx.conf:/etc/nginx/nginx.conf nginx

Check whether a variable is a string in Ruby

In addition to the other answers, Class defines the method === to test whether an object is an instance of that class.

  • o.class class of o.
  • o.instance_of? c determines whether o.class == c
  • o.is_a? c Is o an instance of c or any of it's subclasses?
  • o.kind_of? c synonym for *is_a?*
  • c === o for a class or module, determine if *o.is_a? c* (String === "s" returns true)

Determine if char is a num or letter

You can normally check for ASCII letters or numbers using simple conditions

if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z'))
{
    /*This is an alphabet*/
}

For digits you can use

if (ch >= '0' && ch <= '9')
{
    /*It is a digit*/
}

But since characters in C are internally treated as ASCII values you can also use ASCII values to check the same.

How to check if a character is number or letter

How do you get the logical xor of two variables in Python?

This gets the logical exclusive XOR for two (or more) variables

str1 = raw_input("Enter string one:")
str2 = raw_input("Enter string two:")

any([str1, str2]) and not all([str1, str2])

The first problem with this setup is that it most likely traverses the whole list twice and, at a minimum, will check at least one of the elements twice. So it may increase code comprehension, but it doesn't lend to speed (which may differ negligibly depending on your use case).

The second problem with this setup is that it checks for exclusivity regardless of the number of variables. This is may at first be regarded as a feature, but the first problem becomes a lot more significant as the number of variables increases (if they ever do).

adb remount permission denied, but able to access super user in shell -- android

emulator -writable-system

For people using an Emulator: Another possibility is that you need to start the emulator with -writable-system. That was the only thing that worked for me when using the standard emulator packaged with android studio with a 4.1 image. Check here: https://stackoverflow.com/a/41332316/4962858

Function passed as template argument

Yes, it is valid.

As for making it work with functors as well, the usual solution is something like this instead:

template <typename F>
void doOperation(F f)
{
  int temp=0;
  f(temp);
  std::cout << "Result is " << temp << std::endl;
}

which can now be called as either:

doOperation(add2);
doOperation(add3());

See it live

The problem with this is that if it makes it tricky for the compiler to inline the call to add2, since all the compiler knows is that a function pointer type void (*)(int &) is being passed to doOperation. (But add3, being a functor, can be inlined easily. Here, the compiler knows that an object of type add3 is passed to the function, which means that the function to call is add3::operator(), and not just some unknown function pointer.)

How does spring.jpa.hibernate.ddl-auto property exactly work in Spring?

For the record, the spring.jpa.hibernate.ddl-auto property is Spring Data JPA specific and is their way to specify a value that will eventually be passed to Hibernate under the property it knows, hibernate.hbm2ddl.auto.

The values create, create-drop, validate, and update basically influence how the schema tool management will manipulate the database schema at startup.

For example, the update operation will query the JDBC driver's API to get the database metadata and then Hibernate compares the object model it creates based on reading your annotated classes or HBM XML mappings and will attempt to adjust the schema on-the-fly.

The update operation for example will attempt to add new columns, constraints, etc but will never remove a column or constraint that may have existed previously but no longer does as part of the object model from a prior run.

Typically in test case scenarios, you'll likely use create-drop so that you create your schema, your test case adds some mock data, you run your tests, and then during the test case cleanup, the schema objects are dropped, leaving an empty database.

In development, it's often common to see developers use update to automatically modify the schema to add new additions upon restart. But again understand, this does not remove a column or constraint that may exist from previous executions that is no longer necessary.

In production, it's often highly recommended you use none or simply don't specify this property. That is because it's common practice for DBAs to review migration scripts for database changes, particularly if your database is shared across multiple services and applications.

Getting Git to work with a proxy server - fails with "Request timed out"

I followed the most of the answers which was recommended here. First I got the following error:

fatal: unable to access 'https://github.com/folder/sample.git/': schannel: next InitializeSecurityContext failed: Unknown error (0x80092012) - The revocation function was unable to check revocation for the certificate.

Then I have tried the following command by @Salim Hamidi

git config --global http.proxy http://proxyuser:[email protected]:8080

But I got the following error:

fatal: unable to access 'https://github.com/folder/sample.git/': Received HTTP code 407 from proxy after CONNECT

This could happen if the proxy server can't verify the SSL certificate. So we want to make sure that the ssl verification is off (not recommended for non trusted sites), so I have done the following steps which was recommended by @Arpit but with slight changes:

1.First make sure to remove any previous proxy settings:

git config --global --unset http.proxy

2.Then list and get the gitconfig content

git config --list --show-origin

3.Last update the content of the gitconfig file as below:

[http]
sslCAInfo = C:/yourfolder/AppData/Local/Programs/Git/mingw64/ssl/certs/ca-bundle.crt
sslBackend = schannel
proxy = http://proxyuser:[email protected]:8080
sslverify = false
[https]
proxy = http://proxyuser:[email protected]:8080
sslverify = false

How to detect DataGridView CheckBox event change?

Here is some code:

private void dgvStandingOrder_CellContentClick(object sender, DataGridViewCellEventArgs e)
{
    if (dgvStandingOrder.Columns[e.ColumnIndex].Name == "IsSelected" && dgvStandingOrder.CurrentCell is DataGridViewCheckBoxCell)
    {
        bool isChecked = (bool)dgvStandingOrder[e.ColumnIndex, e.RowIndex].EditedFormattedValue;
        if (isChecked == false)
        {
            dgvStandingOrder.Rows[e.RowIndex].Cells["Status"].Value = "";
        }
        dgvStandingOrder.EndEdit();
    }
}

private void dgvStandingOrder_CellEndEdit(object sender, DataGridViewCellEventArgs e)
{

    dgvStandingOrder.CommitEdit(DataGridViewDataErrorContexts.Commit);
}

private void dgvStandingOrder_CurrentCellDirtyStateChanged(object sender, EventArgs e)
{
    if (dgvStandingOrder.CurrentCell is DataGridViewCheckBoxCell)
    {
        dgvStandingOrder.CommitEdit(DataGridViewDataErrorContexts.Commit);
    }
}

Pointers, smart pointers or shared pointers?

Smart pointers will clean themselves up after they go out of scope (thereby removing fear of most memory leaks). Shared pointers are smart pointers that keep a count of how many instances of the pointer exist, and only clean up the memory when the count reaches zero. In general, only use shared pointers (but be sure to use the correct kind--there is a different one for arrays). They have a lot to do with RAII.

Android device is not connected to USB for debugging (Android studio)

Found out for Samsung, Installing Kies also update the usb driver which solve my problem with connecting my Samsung Galaxy S Advance with Android 4.1.2 to Android Studio on Windows 7 64bit. In this case the devise manager shows device driver is updated and working, but when I connect my phone Android Studio does not recognize my device.

How to get names of classes inside a jar file?

You can use Java jar tool. List the content of jar file in a txt file and you can see all the classes in the jar.

jar tvf jarfile.jar

-t list table of contents for archive

-v generate verbose output on standard output

-f specify archive file name

Angular 6: How to set response type as text while making http call

On your backEnd, you should add:

@RequestMapping(value="/blabla",  produces="text/plain" , method = RequestMethod.GET)

On the frontEnd (Service):

methodBlabla() 
{
  const headers = new HttpHeaders().set('Content-Type', 'text/plain; charset=utf-8');
  return this.http.get(this.url,{ headers, responseType: 'text'});
}

Get day of week using NSDate

Swift 3 : Xcode 8 helper function:

func getDayOfWeek(fromDate date: Date) -> String? {
    let cal = Calendar(identifier: .gregorian)
    let dayOfWeek = cal.component(.weekday, from: date)
    switch dayOfWeek {
     case 1:
        return "Sunday"
    case 2:
        return "Monday"
    case 3:
        return "Tuesday"
    case 4:
        return "Wednesday"
    case 5:
        return "Thursday"
    case 6:
        return "Friday"
    case 7:
        return "Saturday"
    default:
        return nil
    }
}

How can I switch to a tag/branch in hg?

Once you have cloned the repo, you have everything: you can then hg up branchname or hg up tagname to update your working copy.

UP: hg up is a shortcut of hg update, which also has hg checkout alias for people with git habits.

[Microsoft][ODBC Driver Manager] Data source name not found and no default driver specified

Following the instructions here http://help.loftware.com/pages/viewpage.action?pageId=27099554 I had to install the Microsoft Access Database Engine 2010 Redistributable before I had the Excel driver installed to use the DSN-less connection I wanted to use from perl.

How do I rotate the Android emulator display?

Press Ctrl + F10 to rotate the emulator screen.

Gridview get Checkbox.Checked value

If you want a method other than findcontrol try the following:

 GridViewRow row = Gridview1.SelectedRow;
 int CustomerId = int.parse(row.Cells[0].Text);// to get the column value
 CheckBox checkbox1= row.Cells[0].Controls[0] as CheckBox; // you can access the controls like this

Onchange open URL via select - jQuery

If you don't want the url to put it on option's value, i'll give u example :

<select class="abc">
    <option value="0" href="hello">Hell</option>
    <option value="1" href="dello">Dell</option>
    <option value="2" href="cello">Cell</option>
</select>

    $("select").bind('change',function(){
        alert($(':selected',this).attr('href'));
    })

Getting error in console : Failed to load resource: net::ERR_CONNECTION_RESET

In my case i have used .woff files from git repository, and i noticed git has changed my binary files. That with some null character at the file endings. I have rechanged to the orgnal .woff source files and it has corrected!

Also i have understood visual studio controller sending corrupted error like ERR_CONNECTION_RESET from the controller when it gots null character

I shared for all who live this problem

How to remove extension from string (only real extension!)

EDIT: The smartest approach IMHO, it removes the last point and following text from a filename (aka the extension):

$name = basename($filename, '.' . end(explode('.', $filename)));

Cheers ;)

Split data frame string column into multiple columns

Notice that sapply with "[" can be used to extract either the first or second items in those lists so:

before$type_1 <- sapply(strsplit(as.character(before$type),'_and_'), "[", 1)
before$type_2 <- sapply(strsplit(as.character(before$type),'_and_'), "[", 2)
before$type <- NULL

And here's a gsub method:

before$type_1 <- gsub("_and_.+$", "", before$type)
before$type_2 <- gsub("^.+_and_", "", before$type)
before$type <- NULL

How to find length of digits in an integer?

As mentioned the dear user @Calvintwr, the function math.log10 has problem in a number outside of a range [-999999999999997, 999999999999997], where we get floating point errors. I had this problem with the JavaScript (the Google V8 and the NodeJS) and the C (the GNU GCC compiler), so a 'purely mathematically' solution is impossible here.


Based on this gist and the answer the dear user @Calvintwr

import math


def get_count_digits(number: int):
    """Return number of digits in a number."""

    if number == 0:
        return 1

    number = abs(number)

    if number <= 999999999999997:
        return math.floor(math.log10(number)) + 1

    count = 0
    while number:
        count += 1
        number //= 10
    return count

I tested it on numbers with length up to 20 (inclusive) and all right. It must be enough, because the length max integer number on a 64-bit system is 19 (len(str(sys.maxsize)) == 19).

assert get_count_digits(-99999999999999999999) == 20
assert get_count_digits(-10000000000000000000) == 20
assert get_count_digits(-9999999999999999999) == 19
assert get_count_digits(-1000000000000000000) == 19
assert get_count_digits(-999999999999999999) == 18
assert get_count_digits(-100000000000000000) == 18
assert get_count_digits(-99999999999999999) == 17
assert get_count_digits(-10000000000000000) == 17
assert get_count_digits(-9999999999999999) == 16
assert get_count_digits(-1000000000000000) == 16
assert get_count_digits(-999999999999999) == 15
assert get_count_digits(-100000000000000) == 15
assert get_count_digits(-99999999999999) == 14
assert get_count_digits(-10000000000000) == 14
assert get_count_digits(-9999999999999) == 13
assert get_count_digits(-1000000000000) == 13
assert get_count_digits(-999999999999) == 12
assert get_count_digits(-100000000000) == 12
assert get_count_digits(-99999999999) == 11
assert get_count_digits(-10000000000) == 11
assert get_count_digits(-9999999999) == 10
assert get_count_digits(-1000000000) == 10
assert get_count_digits(-999999999) == 9
assert get_count_digits(-100000000) == 9
assert get_count_digits(-99999999) == 8
assert get_count_digits(-10000000) == 8
assert get_count_digits(-9999999) == 7
assert get_count_digits(-1000000) == 7
assert get_count_digits(-999999) == 6
assert get_count_digits(-100000) == 6
assert get_count_digits(-99999) == 5
assert get_count_digits(-10000) == 5
assert get_count_digits(-9999) == 4
assert get_count_digits(-1000) == 4
assert get_count_digits(-999) == 3
assert get_count_digits(-100) == 3
assert get_count_digits(-99) == 2
assert get_count_digits(-10) == 2
assert get_count_digits(-9) == 1
assert get_count_digits(-1) == 1
assert get_count_digits(0) == 1
assert get_count_digits(1) == 1
assert get_count_digits(9) == 1
assert get_count_digits(10) == 2
assert get_count_digits(99) == 2
assert get_count_digits(100) == 3
assert get_count_digits(999) == 3
assert get_count_digits(1000) == 4
assert get_count_digits(9999) == 4
assert get_count_digits(10000) == 5
assert get_count_digits(99999) == 5
assert get_count_digits(100000) == 6
assert get_count_digits(999999) == 6
assert get_count_digits(1000000) == 7
assert get_count_digits(9999999) == 7
assert get_count_digits(10000000) == 8
assert get_count_digits(99999999) == 8
assert get_count_digits(100000000) == 9
assert get_count_digits(999999999) == 9
assert get_count_digits(1000000000) == 10
assert get_count_digits(9999999999) == 10
assert get_count_digits(10000000000) == 11
assert get_count_digits(99999999999) == 11
assert get_count_digits(100000000000) == 12
assert get_count_digits(999999999999) == 12
assert get_count_digits(1000000000000) == 13
assert get_count_digits(9999999999999) == 13
assert get_count_digits(10000000000000) == 14
assert get_count_digits(99999999999999) == 14
assert get_count_digits(100000000000000) == 15
assert get_count_digits(999999999999999) == 15
assert get_count_digits(1000000000000000) == 16
assert get_count_digits(9999999999999999) == 16
assert get_count_digits(10000000000000000) == 17
assert get_count_digits(99999999999999999) == 17
assert get_count_digits(100000000000000000) == 18
assert get_count_digits(999999999999999999) == 18
assert get_count_digits(1000000000000000000) == 19
assert get_count_digits(9999999999999999999) == 19
assert get_count_digits(10000000000000000000) == 20
assert get_count_digits(99999999999999999999) == 20

All example of codes tested with the Python 3.5

What is "origin" in Git?

Git has the concept of "remotes", which are simply URLs to other copies of your repository. When you clone another repository, Git automatically creates a remote named "origin" and points to it.

You can see more information about the remote by typing git remote show origin.

Specifying maxlength for multiline textbox

MaxLength is now supported as of .NET 4.7.2, so as long as you upgrade your project to .NET 4.7.2 or above, it will work automatically.

You can see this in the release notes here - specifically:

Enable ASP.NET developers to specify MaxLength attribute for Multiline asp:TextBox. [449020, System.Web.dll, Bug]

Finding all the subsets of a set

You dont have to mess with recursion and other complex algorithms. You can find all subsets using bit patterns (decimal to binary) of all numbers between 0 and 2^(N-1). Here N is cardinality or number-of-items in that set. The technique is explained here with an implementation and demo.

http://codeding.com/?article=12

How to ignore a particular directory or file for tslint?

As an addition

To disable all rules for the next line // tslint:disable-next-line

To disable specific rules for the next line: // tslint:disable-next-line:rule1 rule2...

To disable all rules for the current line: someCode(); // tslint:disable-line

To disable specific rules for the current line: someCode(); // tslint:disable-line:rule1

How do I concatenate two strings in C?

Without GNU extension:

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

int main(void) {
    const char str1[] = "First";
    const char str2[] = "Second";
    char *res;

    res = malloc(strlen(str1) + strlen(str2) + 1);
    if (!res) {
        fprintf(stderr, "malloc() failed: insufficient memory!\n");
        return EXIT_FAILURE;
    }

    strcpy(res, str1);
    strcat(res, str2);

    printf("Result: '%s'\n", res);
    free(res);
    return EXIT_SUCCESS;
}

Alternatively with GNU extension:

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void) {
    const char str1[] = "First";
    const char str2[] = "Second";
    char *res;

    if (-1 == asprintf(&res, "%s%s", str1, str2)) {
        fprintf(stderr, "asprintf() failed: insufficient memory!\n");
        return EXIT_FAILURE;
    }

    printf("Result: '%s'\n", res);
    free(res);
    return EXIT_SUCCESS;
}

See malloc, free and asprintf for more details.

How to update primary key

If you are sure that this change is suitable for the environment you're working in: set the FK conditions on the secondary tables to UPDATE CASCADING.

For example, if using SSMS as GUI:

  1. right click on the key
  2. select Modify
  3. Fold out 'INSERT And UPDATE Specific'
  4. For 'Update Rule', select Cascade.
  5. Close the dialog and save the key.

When you then update a value in the PK column in your primary table, the FK references in the other tables will be updated to point at the new value, preserving data integrity.

Recursive sub folder search and return files in a list python

If you don't mind installing an additional light library, you can do this:

pip install plazy

Usage:

import plazy

txt_filter = lambda x : True if x.endswith('.txt') else False
files = plazy.list_files(root='data', filter_func=txt_filter, is_include_root=True)

The result should look something like this:

['data/a.txt', 'data/b.txt', 'data/sub_dir/c.txt']

It works on both Python 2.7 and Python 3.

Github: https://github.com/kyzas/plazy#list-files

Disclaimer: I'm an author of plazy.

Displaying tooltip on mouse hover of a text

For the sake of ease of use and understandability.

You can simply put a Tooltip anywhere on your form (from toolbox). You will then be given an options in the Properties of everything else in your form to determine what is displayed in that Tooltip (it reads something like "ToolTip on toolTip1"). Anytime you hover on an object, the text in that property will be displayed as a tooltip.

This does not cover custom on-the-fly tooltips like the original question is asking for. But I am leaving this here for others that do not need

What is the difference between include and require in Ruby?

'Load'- inserts a file's contents.(Parse file every time the file is being called)

'Require'- inserts a file parsed content.(File parsed once and stored in memory)

'Include'- includes the module into the class and can use methods inside the module as class's instance method

'Extend'- includes the module into the class and can use methods inside the module as class method

socket.emit() vs. socket.send()

Simple and precise (Source: Socket.IO google group):

socket.emit allows you to emit custom events on the server and client

socket.send sends messages which are received with the 'message' event