Programs & Examples On #Tunneling

Tunneling is a technique that enables remote access users to connect to a variety of network resources through a public data network.

ssh: check if a tunnel is alive

We can check using ps command

# ps -aux | grep ssh

Will show all shh service running and we can find the tunnel service listed

How to pass command line arguments to a rake task

One thing I don't see here is how to handle arbitrary arguments. If you pass arguments that are not listed in the task definition, they are still accessible under args.extras:

task :thing, [:foo] do |task, args|
  puts args[:foo]     # named argument
  puts args.extras    # any additional arguments that were passed
end

Get Date in YYYYMMDD format in windows batch file

If, after reading the other questions and viewing the links mentioned in the comment sections, you still can't figure it out, read on.

First of all, where you're going wrong is the offset.

It should look more like this...

set mydate=%date:~10,4%%date:~6,2%/%date:~4,2%
echo %mydate%

If the date was Tue 12/02/2013 then it would display it as 2013/02/12.

To remove the slashes, the code would look more like

set mydate=%date:~10,4%%date:~7,2%%date:~4,2%
echo %mydate%

which would output 20130212

And a hint for doing it in the future, if mydate equals something like %date:~10,4%%date:~7,2% or the like, you probably forgot a tilde (~).

Execute script after specific delay using JavaScript

I had some ajax commands I wanted to run with a delay in between. Here is a simple example of one way to do that. I am prepared to be ripped to shreds though for my unconventional approach. :)

//  Show current seconds and milliseconds
//  (I know there are other ways, I was aiming for minimal code
//  and fixed width.)
function secs()
{
    var s = Date.now() + ""; s = s.substr(s.length - 5);
  return s.substr(0, 2) + "." + s.substr(2);
}

//  Log we're loading
console.log("Loading: " + secs());

//  Create a list of commands to execute
var cmds = 
[
    function() { console.log("A: " + secs()); },
    function() { console.log("B: " + secs()); },
    function() { console.log("C: " + secs()); },
    function() { console.log("D: " + secs()); },
    function() { console.log("E: " + secs()); },
  function() { console.log("done: " + secs()); }
];

//  Run each command with a second delay in between
var ms = 1000;
cmds.forEach(function(cmd, i)
{
    setTimeout(cmd, ms * i);
});

// Log we've loaded (probably logged before first command)
console.log("Loaded: " + secs());

You can copy the code block and paste it into a console window and see something like:

Loading: 03.077
Loaded: 03.078
A: 03.079
B: 04.075
C: 05.075
D: 06.075
E: 07.076
done: 08.076

Enable PHP Apache2

You have two ways to enable it.

First, you can set the absolute path of the php module file in your httpd.conf file like this:

LoadModule php5_module /path/to/mods-available/libphp5.so

Second, you can link the module file to the mods-enabled directory:

ln -s /path/to/mods-available/libphp5.so /path/to/mods-enabled/libphp5.so

How to schedule a function to run every hour on Flask?

You could try using APScheduler's BackgroundScheduler to integrate interval job into your Flask app. Below is the example that uses blueprint and app factory (init.py) :

from datetime import datetime

# import BackgroundScheduler
from apscheduler.schedulers.background import BackgroundScheduler
from flask import Flask

from webapp.models.main import db 
from webapp.controllers.main import main_blueprint    

# define the job
def hello_job():
    print('Hello Job! The time is: %s' % datetime.now())

def create_app(object_name):
    app = Flask(__name__)
    app.config.from_object(object_name)
    db.init_app(app)
    app.register_blueprint(main_blueprint)
    # init BackgroundScheduler job
    scheduler = BackgroundScheduler()
    # in your case you could change seconds to hours
    scheduler.add_job(hello_job, trigger='interval', seconds=3)
    scheduler.start()

    try:
        # To keep the main thread alive
        return app
    except:
        # shutdown if app occurs except 
        scheduler.shutdown()

Hope it helps :)

Ref :

  1. https://github.com/agronholm/apscheduler/blob/master/examples/schedulers/background.py

Windows XP or later Windows: How can I run a batch file in the background with no window displayed?

You can run your .bat file through a .vbs file
Copy the following code into your .vbs file :

Dim WshShell
Dim obj
Set WshShell = WScript.CreateObject("WScript.Shell") 
obj = WshShell.Run("C:\Users\file1.bat", 0) 
obj = WshShell.Run("C:\Users\file2.bat", 0)  and so on
set WshShell = Nothing 

How to insert a line break in a SQL Server VARCHAR/NVARCHAR string

All of these options work depending on your situation, but you may not see any of them work if you're using SSMS (as mentioned in some comments SSMS hides CR/LFs)

So rather than driving yourself round the bend, Check this setting in

Tools | Options

which will replace the

How to convert a boolean array to an int array

I know you asked for non-looping solutions, but the only solutions I can come up with probably loop internally anyway:

map(int,y)

or:

[i*1 for i in y]

or:

import numpy
y=numpy.array(y)
y*1

Angular 4: How to include Bootstrap?

In Angular4 as you deal with @types system, you should do following things,

Do,

1) npm install --save @types/jquery
2) npm install --save @types/bootstrap

tsconfig.json

look for types array and add jquery and bootstrap entries,

"types": [
      "jquery",
      "bootstrap",  
      "node"
]

Index.html

in head section add following entries,

  <link href="node_modules/bootstrap/dist/css/bootstrap.min.css" rel="stylesheet">
  <script src="node_modules/jquery/dist/jquery.min.js "></script>
  <script src="node_modules/bootstrap/dist/js/bootstrap.js "></script>

And start using jquery and bootstrap both.

CodeIgniter - accessing $config variable in view

$this->config->item() works fine.

For example, if the config file contains $config['foo'] = 'bar'; then $this->config->item('foo') == 'bar'

How to figure out the SMTP server host?

To automate the answer of @Jordan S. Jones at WIN/DOS command-line,

Put this in a batch file named: getmns.bat (get mail name server):

@echo off
if @%1==@ goto USAGE
echo set type=MX>mnscmd.txt
echo %1>>mnscmd.txt
echo exit>>mnscmd.txt
nslookup<mnscmd.txt>mnsresult.txt
type mnsresult.txt
del mnsresult.txt
goto END
:USAGE
echo usage:
echo %0 domainname.ext
:END
echo.

For example:

getmns google.com

output:

google.com      MX preference = 20, mail exchanger = alt1.aspmx.l.google.com
google.com      MX preference = 10, mail exchanger = aspmx.l.google.com
google.com      MX preference = 50, mail exchanger = alt4.aspmx.l.google.com
google.com      MX preference = 40, mail exchanger = alt3.aspmx.l.google.com
google.com      MX preference = 30, mail exchanger = alt2.aspmx.l.google.com

alt4.aspmx.l.google.com internet address = 74.125.25.27
alt3.aspmx.l.google.com internet address = 173.194.72.27
aspmx.l.google.com      internet address = 173.194.65.27
alt1.aspmx.l.google.com internet address = 74.125.200.27
alt2.aspmx.l.google.com internet address = 64.233.187.27

For example to pipe the result again into a file do:

getmns google.com > google.mns.txt

:-D

Basic HTTP and Bearer Token Authentication

I had a similar problem - authenticate device and user at device. I used a Cookie header alongside an Authorization: Bearer... header. One header authenticated the device, the other authenticated the user. I used a Cookie header because these are commonly used for authentication.

How to use ES6 Fat Arrow to .filter() an array of objects

You can't implicitly return with an if, you would need the braces:

let adults = family.filter(person => { if (person.age > 18) return person} );

It can be simplified though:

let adults = family.filter(person => person.age > 18);

Create Generic method constraining T to an Enum

You can define a static constructor for the class that will check that the type T is an enum and throw an exception if it is not. This is the method mentioned by Jeffery Richter in his book CLR via C#.

internal sealed class GenericTypeThatRequiresAnEnum<T> {
    static GenericTypeThatRequiresAnEnum() {
        if (!typeof(T).IsEnum) {
        throw new ArgumentException("T must be an enumerated type");
        }
    }
}

Then in the parse method, you can just use Enum.Parse(typeof(T), input, true) to convert from string to the enum. The last true parameter is for ignoring case of the input.

Batch program to to check if process exists

TASKLIST does not set errorlevel.

echo off
tasklist /fi "imagename eq notepad.exe" |find ":" > nul
if errorlevel 1 taskkill /f /im "notepad.exe"
exit

should do the job, since ":" should appear in TASKLIST output only if the task is NOT found, hence FIND will set the errorlevel to 0 for not found and 1 for found

Nevertheless,

taskkill /f /im "notepad.exe"

will kill a notepad task if it exists - it can do nothing if no notepad task exists, so you don't really need to test - unless there's something else you want to do...like perhaps

echo off
tasklist /fi "imagename eq notepad.exe" |find ":" > nul
if errorlevel 1 taskkill /f /im "notepad.exe"&exit

which would appear to do as you ask - kill the notepad process if it exists, then exit - otherwise continue with the batch

Equal height rows in a flex container

The answer is NO.

The reason is provided in the flexbox specification:

6. Flex Lines

In a multi-line flex container, the cross size of each line is the minimum size necessary to contain the flex items on the line.

In other words, when there are multiple lines in a row-based flex container, the height of each line (the "cross size") is the minimum height necessary to contain the flex items on the line.

Equal height rows, however, are possible in CSS Grid Layout:

Otherwise, consider a JavaScript alternative.

How to get the background color of an HTML element?

It depends which style from the div you need. Is this a background style which was defined in CSS or background style which was added through javascript(inline) to the current node?

In case of CSS style, you should use computed style. Like you do in getStyle().

With inline style you should use node.style reference: x.style.backgroundColor;

Also notice, that you pick the style by using camelCase/non hyphen reference, so not background-color, but backgroundColor;

What does java.lang.Thread.interrupt() do?

An interrupt is an indication to a thread that it should stop what it is doing and do something else. It's up to the programmer to decide exactly how a thread responds to an interrupt, but it is very common for the thread to terminate. A very good referance: https://docs.oracle.com/javase/tutorial/essential/concurrency/interrupt.html

Binding Combobox Using Dictionary as the Datasource

A dictionary cannot be directly used as a data source, you should do more.

SortedDictionary<string, int> userCache =  UserCache.getSortedUserValueCache();
KeyValuePair<string, int> [] ar= new KeyValuePair<string,int>[userCache.Count];
userCache.CopyTo(ar, 0);
comboBox1.DataSource = ar; new BindingSource(ar, "Key"); //This line is causing the error
comboBox1.DisplayMember = "Value";
comboBox1.ValueMember = "Key";

How to find the most recent file in a directory using .NET, and without looping?

Another approach if you are using Directory.EnumerateFiles and want to read files in latest modified by first.

foreach (string file in Directory.EnumerateFiles(fileDirectory, fileType).OrderByDescending(f => new FileInfo(f).LastWriteTime))

}

mySQL select IN range

To select data in numerical range you can use BETWEEN which is inclusive.

SELECT JOB FROM MYTABLE WHERE ID BETWEEN 10 AND 15;

Codeigniter: does $this->db->last_query(); execute a query?

For me save_queries option was turned off so,

$this->db->save_queries = TRUE; //Turn ON save_queries for temporary use.
$str = $this->db->last_query();
echo $str;

Ref: Can't get result from $this->db->last_query(); codeigniter

Google Map API - Removing Markers

Following code might be useful if someone is using React and has a different component of Marker and want to remove marker from map.

export default function useGoogleMapMarker(props) {
  const [marker, setMarker] = useState();

  useEffect(() => {
    // ...code
    const marker = new maps.Marker({ position, map, title, icon });
    // ...code
    setMarker(marker);
    return () => marker.setMap(null); // to remove markers when unmounts
  }, []);

  return marker;
}

How to open Console window in Eclipse?

From the menu bar, Window → Show View → Console. Alternately, use the keyboard shortcut:

  • Mac: Option-Command-Q, then C, or
  • Windows: Alt-Shift-Q, then C

enter image description here

Could not load file or assembly 'EntityFramework' after downgrading EF 5.0.0.0 --> 4.3.1.0

public Configuration()
{
    AutomaticMigrationsEnabled = false;

    // register mysql code generator

    SetSqlGenerator("MySql.Data.MySqlClient", new MySql.Data.Entity.MySqlMigrationSqlGenerator());
}

I find out that connector 6.6.4 will not work with Entity Framework 5 but with Entity Framework 4.3. So to downgrade issue the following commands in the package manager console:

Uninstall-Package EntityFramework

Install-Package EntityFramework -Version 4.3.1

Finally I do Update-Database -Verbose again and voila! The schema and tables are created. Wait for the next version of connector to use it with Entity Framework 5.

Full Screen DialogFragment in Android

I met the issue before when using a fullscreen dialogFragment: there is always a padding while having set fullscreen. try this code in dialogFragment's onActivityCreated() method:

public void onActivityCreated(Bundle savedInstanceState)
{   
    super.onActivityCreated(savedInstanceState);
    Window window = getDialog().getWindow();
    LayoutParams attributes = window.getAttributes();
    //must setBackgroundDrawable(TRANSPARENT) in onActivityCreated()
    window.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
    if (needFullScreen)
    {
        window.setLayout(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
    }
}

Hibernate dialect for Oracle Database 11g?

At least in case of EclipseLink 10g and 11g differ. Since 11g it is not recommended to use first_rows hint for pagination queries.

See "Is it possible to disable jpa hints per particular query". Such a query should not be used in 11g.

SELECT * FROM (
  SELECT /*+ FIRST_ROWS */ a.*, ROWNUM rnum  FROM (
    SELECT * FROM TABLES INCLUDING JOINS, ORDERING, etc.) a
  WHERE ROWNUM <= 10 )
WHERE rnum > 0;

But there can be other nuances.

background: fixed no repeat not working on mobile

I have found a great solution for fixed backgrounds on mobile devices requiring no JavaScript at all.

body:before {
  content: "";
  display: block;
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  z-index: -10;
  background: url(photos/2452.jpg) no-repeat center center;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}

Please be aware of the negative z-index value of -10. html root element default z-index is 0. This value must be the smallest z-index to have it as background.

Spark : how to run spark file from spark shell

You can use either sbt or maven to compile spark programs. Simply add the spark as dependency to maven

<repository>
      <id>Spark repository</id>
      <url>http://www.sparkjava.com/nexus/content/repositories/spark/</url>
</repository>

And then the dependency:

<dependency>
      <groupId>spark</groupId>
      <artifactId>spark</artifactId>
      <version>1.2.0</version>
</dependency>

In terms of running a file with spark commands: you can simply do this:

echo"
   import org.apache.spark.sql.*
   ssc = new SQLContext(sc)
   ssc.sql("select * from mytable").collect
" > spark.input

Now run the commands script:

cat spark.input | spark-shell

CSS Change List Item Background Color with Class

Scenario: I have a navigation menu like this. Note: Link <a> is child of list item <li>. I wanted to change the background of the selected list item and remove the background color of unselected list item.

<nav>
        <ul>
            <li><a href="#">Intro</a></li>
            <li><a href="#">Size</a></li>
            <li><a href="#">Play</a></li>
            <li><a href="#">Food</a></li>
        </ul>
        <div class="clear"></div>

       </nav>

I tried to add a class .active into the list item using jQuery but it was not working

.active
{
    background-color: #480048;
}

$("nav li a").click(function () {
        $(this).parent().addClass("active");
        $(this).parent().siblings().removeClass("active");
    });

Solution: Basically, using .active class changing the background-color of list item does not work. So I changed the css class name from .active to "nav li.active a" so using the same javascript it will add the .active class into the selected list item. Now if the list item <li> has .active class then css will change the background color of the child of that list item <a>.

nav li.active a
{
    background-color: #480048;
}

Tab space instead of multiple non-breaking spaces ("nbsp")?

If whitespace becomes that important, it may be better to use preformatted text and the <pre> tag.

Background blur with CSS

There is a simple and very common technique by using 2 background images: a crisp and a blurry one. You set the crisp image as a background for the body and the blurry one as a background image for your container. The blurry image must be set to fixed positioning and the alignment is 100% perfect. I used it before and it works.

body {
    background: url(yourCrispImage.jpg) no-repeat;
}

#container {
    background: url(yourBlurryImage.jpg) no-repeat fixed;
}

You can see a working example at the following fiddle: http://jsfiddle.net/jTUjT/5/. Try to resize the browser and see that the alignment never fails.


If only CSS element() was supported by other browsers other than Mozilla's -moz-element() you could create great effects. See this demo with Mozilla.

Does Python have a ternary conditional operator?

Ternary conditional operator simply allows testing a condition in a single line replacing the multiline if-else making the code compact.

Syntax :

[on_true] if [expression] else [on_false]

1- Simple Method to use ternary operator:

# Program to demonstrate conditional operator
a, b = 10, 20
# Copy value of a in min if a < b else copy b
min = a if a < b else b
print(min)  # Output: 10

2- Direct Method of using tuples, Dictionary, and lambda:

# Python program to demonstrate ternary operator
a, b = 10, 20
# Use tuple for selecting an item
print( (b, a) [a < b] )
# Use Dictionary for selecting an item
print({True: a, False: b} [a < b])
# lamda is more efficient than above two methods
# because in lambda  we are assure that
# only one expression will be evaluated unlike in
# tuple and Dictionary
print((lambda: b, lambda: a)[a < b]()) # in output you should see three 10

3- Ternary operator can be written as nested if-else:

# Python program to demonstrate nested ternary operator
a, b = 10, 20
print ("Both a and b are equal" if a == b else "a is greater than b"
        if a > b else "b is greater than a")

Above approach can be written as:

# Python program to demonstrate nested ternary operator
a, b = 10, 20
if a != b:
    if a > b:
        print("a is greater than b")
    else:
        print("b is greater than a")
else:
    print("Both a and b are equal") 
# Output: b is greater than a

Is it possible to use jQuery .on and hover?

$("#MyTableData").on({

 mouseenter: function(){

    //stuff to do on mouse enter
    $(this).css({'color':'red'});

},
mouseleave: function () {
    //stuff to do on mouse leave
    $(this).css({'color':'blue'});

}},'tr');

Format Date time in AngularJS

we can format the date on view side in angular is very easy....please check the below example:

{{dt | date : "dd-MM-yyyy"}}

Can you style an html radio button to look like a checkbox?

This is my solution using only CSS (Jsfiddle: http://jsfiddle.net/xykPT/).

enter image description here

_x000D_
_x000D_
div.options > label > input {_x000D_
 visibility: hidden;_x000D_
}_x000D_
_x000D_
div.options > label {_x000D_
 display: block;_x000D_
 margin: 0 0 0 -10px;_x000D_
 padding: 0 0 20px 0;  _x000D_
 height: 20px;_x000D_
 width: 150px;_x000D_
}_x000D_
_x000D_
div.options > label > img {_x000D_
 display: inline-block;_x000D_
 padding: 0px;_x000D_
 height:30px;_x000D_
 width:30px;_x000D_
 background: none;_x000D_
}_x000D_
_x000D_
div.options > label > input:checked +img {  _x000D_
 background: url(http://cdn1.iconfinder.com/data/icons/onebit/PNG/onebit_34.png);_x000D_
 background-repeat: no-repeat;_x000D_
 background-position:center center;_x000D_
 background-size:30px 30px;_x000D_
}
_x000D_
<div class="options">_x000D_
 <label title="item1">_x000D_
  <input type="radio" name="foo" value="0" /> _x000D_
  Item 1_x000D_
  <img />_x000D_
 </label>_x000D_
 <label title="item2">_x000D_
  <input type="radio" name="foo" value="1" />_x000D_
  Item 2_x000D_
  <img />_x000D_
 </label>   _x000D_
 <label title="item3">_x000D_
  <input type="radio" name="foo" value="2" />_x000D_
  Item 3_x000D_
  <img />_x000D_
 </label>_x000D_
</div>
_x000D_
_x000D_
_x000D_

NSDictionary - Need to check whether dictionary contains key-value pair or not

With literal syntax you can check as follows

static const NSString* kKeyToCheck = @"yourKey"
if (xyz[kKeyToCheck])
  NSLog(@"Key: %@, has Value: %@", kKeyToCheck, xyz[kKeyToCheck]);
else
 NSLog(@"Key pair do not exits for key: %@", kKeyToCheck); 

Printing everything except the first field with awk

If you're open to another Perl solution:

perl -ple 's/^(\S+)\s+(.*)/$2 $1/' file

How to create an empty DataFrame with a specified schema?

import scala.reflect.runtime.{universe => ru}
def createEmptyDataFrame[T: ru.TypeTag] =
    hiveContext.createDataFrame(sc.emptyRDD[Row],
      ScalaReflection.schemaFor(ru.typeTag[T].tpe).dataType.asInstanceOf[StructType]
    )
  case class RawData(id: String, firstname: String, lastname: String, age: Int)
  val sourceDF = createEmptyDataFrame[RawData]

What's the key difference between HTML 4 and HTML 5?

You'll want to check HTML5 Differences from HTML4: W3C Working Group Note 9 December 2014 for the complete differences. There are many new elements and element attributes. Some elements were removed and others have different semantic value than before.

There are also APIs defined, such as the use of canvas, to help build the next generation of web apps and make sure implementations are standardized.

Eclipse: Set maximum line length for auto formatting?

for XML line width, update preferences > XML > XML Files > Editor > Line width

Oracle 11g SQL to get unique values in one column of a multi-column query

For efficiency's sake you want to only hit the data once, as Harper does. However you don't want to use rank() because it will give you ties and further you want to group by language rather than order by language. From there you want add an order by clause to distinguish between rows, but you don't want to actually sort the data. To achieve this I would use "order by null" E.g.

count(*) over (group by language order by null)

What is the best JavaScript code to create an img element

Just for the sake of completeness, I would suggest using the InnerHTML way as well - even though I would not call it the best way...

document.getElementById("image-holder").innerHTML = "<img src='image.png' alt='The Image' />";

By the way, innerHTML is not that bad

Storing Form Data as a Session Variable

You can solve this problem using this code:

if(!empty($_GET['variable from which you get'])) 
{
$_SESSION['something']= $_GET['variable from which you get'];
}

So you get the variable from a GET form, you will store in the $_SESSION['whatever'] variable just once when $_GET['variable from which you get']is set and if it is empty $_SESSION['something'] will store the old parameter

How can I test a change made to Jenkinsfile locally?

For simplicity, you can create a Jenkinsfile at the root of the git repository, similar to the below example 'Jenkinsfile' based on the groovy syntax of the declarative pipeline.

pipeline {

    agent any

    stages {
        stage('Build the Project') {
            steps {
                git 'https://github.com/jaikrgupta/CarthageAPI-1.0.git'
                echo pwd()
                sh 'ls -alrt'
                sh 'pip install -r requirements.txt'
                sh 'python app.py &'
                echo "Build stage gets finished here"
            }
        }
        stage('Test') {
            steps {
                sh 'chmod 777 ./scripts/test-script.sh'
                sh './scripts/test-script.sh'
                sh 'cat ./test-reports/test_script.log'
                echo "Test stage gets finished here"
            }
        }
}

https://github.com/jaikrgupta/CarthageAPI-1.0.git

You can now set up a new item in Jenkins as a Pipeline job. Select the Definition as Pipeline script from SCM and Git for the SCM option. Paste the project's git repo link in the Repository URL and Jenkinsfile in the script name box. Then click on the lightweight checkout option and save the project. So whenever you pushed a commit to the git repo, you can always test the changes running the Build Now every time in Jenkins.

Please follow the instructions in the below visuals for easy setup a Jenkins Pipeline's job.

enter image description here

enter image description here

enter image description here

enter image description here

enter image description here

How to get image width and height in OpenCV?

Also for openCV in python you can do:

img = cv2.imread('myImage.jpg')
height, width, channels = img.shape 

What is a wrapper class?

Java programming provides wrapper class for each primitive data types, to convert a primitive data types to correspond object of wrapper class.

How to split data into trainset and testset randomly?

You could also use numpy. When your data is stored in a numpy.ndarray:

import numpy as np
from random import sample
l = 100 #length of data 
f = 50  #number of elements you need
indices = sample(range(l),f)

train_data = data[indices]
test_data = np.delete(data,indices)

return value after a promise

Use a pattern along these lines:

function getValue(file) {
  return lookupValue(file);
}

getValue('myFile.txt').then(function(res) {
  // do whatever with res here
});

(although this is a bit redundant, I'm sure your actual code is more complicated)

How to find all links / pages on a website

Another alternative might be

Array.from(document.querySelectorAll("a")).map(x => x.href)

With your $$( its even shorter

Array.from($$("a")).map(x => x.href)

Is it possible to make a Tree View with Angular?

Have a look at this fiddle

Original: http://jsfiddle.net/brendanowen/uXbn6/8/

Updated: http://jsfiddle.net/animaxf/uXbn6/4779/

This should give you a good idea of how to display a tree like structure using angular. It is kind of using recursion in html!

What does the NS prefix mean?

From Apple's developer docs:

Historical Note: If you’re wondering why so many of the classes you encounter have an NS prefix, it’s because of the past history of Cocoa and Cocoa Touch. Cocoa began life as the collected frameworks used to build apps for the NeXTStep operating system. When Apple purchased NeXT back in 1996, much of NeXTStep was incorporated into OS X, including the existing class names. Cocoa Touch was introduced as the iOS equivalent of Cocoa; some classes are available in both Cocoa and Cocoa Touch, though there are also a large number of classes unique to each platform. Two-letter prefixes like NS and UI (for User Interface elements on iOS) are reserved for use by Apple.

Source: Programming with Objective-C

Java: Unresolved compilation problem

Make sure you have removed unavailable libraries (jar files) from build path

How to check if array element exists or not in javascript?

Use typeof arrayName[index] === 'undefined'

i.e.

if(typeof arrayName[index] === 'undefined') {
    // does not exist
}
else {
    // does exist
}

How do I add a foreign key to an existing SQLite table?

First add a column in child table Cid as int then alter table with the code below. This way you can add the foreign key Cid as the primary key of parent table and use it as the foreign key in child table ... hope it will help you as it is good for me:

ALTER TABLE [child] 
  ADD CONSTRAINT [CId] 
  FOREIGN KEY ([CId]) 
  REFERENCES [Parent]([CId]) 
  ON DELETE CASCADE ON UPDATE NO ACTION;
GO

Exclude Blank and NA in R

A good idea is to set all of the "" (blank cells) to NA before any further analysis.

If you are reading your input from a file, it is a good choice to cast all "" to NAs:

foo <- read.table(file="Your_file.txt", na.strings=c("", "NA"), sep="\t") # if your file is tab delimited

If you have already your table loaded, you can act as follows:

foo[foo==""] <- NA

Then to keep only rows with no NA you may just use na.omit():

foo <- na.omit(foo)

Or to keep columns with no NA:

foo <- foo[, colSums(is.na(foo)) == 0] 

jQuery check if <input> exists and has a value

You could do:

if($('.input1').length && $('.input1').val().length)

length evaluates to false in a condition, when the value is 0.

Placing a textview on top of imageview in android

you can try this too. I use just framelayout.

 <FrameLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="@drawable/cover"
                android:gravity="bottom">

                <TextView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:textAppearance="?android:attr/textAppearanceMedium"
                    android:text="Hello !"
                    android:id="@+id/welcomeTV"
                    android:textColor="@color/textColor"
                    android:layout_gravity="left|bottom" />
            </FrameLayout>

How to merge rows in a column into one cell in excel?

I use the CONCATENATE method to take the values of a column and wrap quotes around them with columns in between in order to quickly populate the WHERE IN () clause of a SQL statement.

I always just type =CONCATENATE("'",B2,"'",",") and then select that and drag it down, which creates =CONCATENATE("'",B3,"'",","), =CONCATENATE("'",B4,"'",","), etc. then highlight that whole column, copy paste to a plain text editor and paste back if needed, thus stripping the row separation. It works, but again, just as a one time deal, this is not a good solution for someone who needs this all the time.

What is AF_INET, and why do I need it?

AF_INET is an address family that is used to designate the type of addresses that your socket can communicate with (in this case, Internet Protocol v4 addresses). When you create a socket, you have to specify its address family, and then you can only use addresses of that type with the socket. The Linux kernel, for example, supports 29 other address families such as UNIX (AF_UNIX) sockets and IPX (AF_IPX), and also communications with IRDA and Bluetooth (AF_IRDA and AF_BLUETOOTH, but it is doubtful you'll use these at such a low level).

For the most part, sticking with AF_INET for socket programming over a network is the safest option. There is also AF_INET6 for Internet Protocol v6 addresses.

Hope this helps,

EF Code First "Invalid column name 'Discriminator'" but no inheritance

I had a similar problem, not exactly the same conditions and then i saw this post. Hope it helps someone. Apparently i was using one of my EF entity models a base class for a type that was not specified as a db set in my dbcontext. To fix this issue i had to create a base class that had all the properties common to the two types and inherit from the new base class among the two types.

Example:

//Bad Flow
    //class defined in dbcontext as a dbset
    public class Customer{ 
       public int Id {get; set;}
       public string Name {get; set;}
    }

    //class not defined in dbcontext as a dbset
    public class DuplicateCustomer:Customer{ 
       public object DuplicateId {get; set;}
    }


    //Good/Correct flow*
    //Common base class
    public class CustomerBase{ 
       public int Id {get; set;}
       public string Name {get; set;}
    }

    //entity model referenced in dbcontext as a dbset
    public class Customer: CustomerBase{

    }

    //entity model not referenced in dbcontext as a dbset
    public class DuplicateCustomer:CustomerBase{

       public object DuplicateId {get; set;}

    }

What is the difference between IQueryable<T> and IEnumerable<T>?

We use IEnumerable and IQueryable to manipulate the data that is retrieved from database. IQueryable inherits from IEnumerable, so IQueryable does contain all the IEnumerable features. The major difference between IQueryable and IEnumerable is that IQueryable executes query with filters whereas IEnumerable executes the query first and then it filters the data based on conditions.

Find more detailed differentiation below :

IEnumerable

  1. IEnumerable exists in the System.Collections namespace
  2. IEnumerable execute a select query on the server side, load data in-memory on a client-side and then filter data
  3. IEnumerable is suitable for querying data from in-memory collections like List, Array
  4. IEnumerable is beneficial for LINQ to Object and LINQ to XML queries

IQueryable

  1. IQueryable exists in the System.Linq namespace
  2. IQueryable executes a 'select query' on server-side with all filters
  3. IQueryable is suitable for querying data from out-memory (like remote database, service) collections
  4. IQueryable is beneficial for LINQ to SQL queries

So IEnumerable is generally used for dealing with in-memory collection, whereas, IQueryable is generally used to manipulate collections.

How to add months to a date in JavaScript?

I would highly recommend taking a look at datejs. With it's api, it becomes drop dead simple to add a month (and lots of other date functionality):

var one_month_from_your_date = your_date_object.add(1).month();

What's nice about datejs is that it handles edge cases, because technically you can do this using the native Date object and it's attached methods. But you end up pulling your hair out over edge cases, which datejs has taken care of for you.

Plus it's open source!

How to convert a list of numbers to jsonarray in Python

Use the json module to produce JSON output:

import json

with open(outputfilename, 'wb') as outfile:
    json.dump(row, outfile)

This writes the JSON result directly to the file (replacing any previous content if the file already existed).

If you need the JSON result string in Python itself, use json.dumps() (added s, for 'string'):

json_string = json.dumps(row)

The L is just Python syntax for a long integer value; the json library knows how to handle those values, no L will be written.

Demo string output:

>>> import json
>>> row = [1L,[0.1,0.2],[[1234L,1],[134L,2]]]
>>> json.dumps(row)
'[1, [0.1, 0.2], [[1234, 1], [134, 2]]]'

XPath - Difference between node() and text()

For me it was a big difference when I faced this scenario (here my story:)

<?xml version="1.0" encoding="UTF-8"?>
<sentence id="S1.6">When U937 cells were infected with HIV-1, 
        
    <xcope id="X1.6.3">
        <cue ref="X1.6.3" type="negation">no</cue> 
                        
                        induction of NF-KB factor was detected
        
    </xcope>
                    
, whereas high level of progeny virions was produced, 
        
    <xcope id="X1.6.2">
        <cue ref="X1.6.2" type="speculation">suggesting</cue> that this factor was 
        <xcope id="X1.6.1">
            <cue ref="X1.6.1" type="negation">not</cue> required for viral replication
        </xcope>
    </xcope>.

</sentence>

I needed to extract text between tags and aggregate (by concat) the text including in innner tags.

/node() did the job, while /text() made half job

/text() only returned text not included in inner tags, because inner tags are not "text nodes". You may think, "just extract text included in the inner tags in an additional xpath", however, it becomes challenging to sort the text in this original order because you dont know where to place the aggregated text from the inner tags!because you dont know where to place the aggregated text from the inner nodes.

  1. When U937 cells were infected with HIV-1,
  2. no induction of NF-KB factor was detected
  3. , whereas high level of progeny virions was produced,
  4. suggesting that this factor was not required for viral replication
  5. .

Finally, /node() did exactly what I wanted, because it gets the text from inner tags too.

Twitter Bootstrap Modal Form Submit

Simple

<div class="modal-footer">
<button class="btn" data-dismiss="modal" aria-hidden="true">Close</button>
<button class="btn btn-primary" onclick="event.preventDefault();document.getElementById('your-form').submit();">Save changes</button>

Convert Map<String,Object> to Map<String,String>

Great solutions here, just one more option that taking into consideration handling of null values:

Map<String,Object> map = new HashMap<>();

Map<String,String> stringifiedMap = map.entrySet().stream()
             .filter(m -> m.getKey() != null && m.getValue() !=null)
             .collect(Collectors.toMap(Map.Entry::getKey, e -> (String)e.getValue()));

angularjs: allows only numbers to be typed into a text box

I know this is an old post but this adaptation of My Mai's answer works nicely for me...

angular.module("app").directive("numbersOnly", function() {
  return {
    require: "ngModel",
    restrict: "A",
    link: function(scope, element, attr, ctrl) {
        function inputValue(val) {
            if (val) {
                //transform val to a string so replace works
                var myVal = val.toString();

                //replace any non numeric characters with nothing
                var digits = myVal.replace(/\D/g, "");

                //if anything needs replacing - do it!
                if (digits !== myVal) {
                    ctrl.$setViewValue(digits);
                    ctrl.$render();
                }
                return parseFloat(digits);
            }
            return undefined;
        }
        ctrl.$parsers.push(inputValue);
    }
  };
});

How to vertically align <li> elements in <ul>?

Here's a good one:

Set line-height equal to whatever the height is; works like a charm!

E.g:

li {
    height: 30px;
    line-height: 30px;
}

Is there a pretty print for PHP?

Expanding on @stephen's answer, added a few very minor tweaks for display purposes.

function pp($arr){
    $retStr = '<ul>';
    if (is_array($arr)){
        foreach ($arr as $key=>$val){
            if (is_array($val)){
                $retStr .= '<li>' . $key . ' => array(' . pp($val) . '),</li>';
            }else{
                $retStr .= '<li>' . $key . ' => ' . ($val == '' ? '""' : $val) . ',</li>';
            }
        }
    }
    $retStr .= '</ul>';
    return $retStr;
}

Will format any multidimensional array like so:

enter image description here

How to find and replace with regex in excel

As an alternative to Regex, running:

Sub Replacer()
   Dim N As Long, i As Long
   N = Cells(Rows.Count, "A").End(xlUp).Row

   For i = 1 To N
      If Left(Cells(i, "A").Value, 9) = "texts are" Then
         Cells(i, "A").Value = "texts are replaced"
      End If
   Next i
End Sub

will produce:

enter image description here

how to execute php code within javascript

If you do not want to include the jquery library you can simple do the following

a) ad an iframe, size 0px so it is not visible, href is blank

b) execute this within your js code function

 window.frames['iframename'].location.replace('http://....your.php');

This will execute the php script and you can for example make a database update...

Using a dictionary to select function to execute

You can just use

myDict = {
    "P1": (lambda x: function1()),
    "P2": (lambda x: function2()),
    ...,
    "Pn": (lambda x: functionn())}
myItems = ["P1", "P2", ..., "Pn"]

for item in myItems:
    myDict[item]()

Escaping quotation marks in PHP

Save your text not in a PHP file, but in an ordinary text file called, say, "text.txt"

Then with one simple $text1 = file_get_contents('text.txt'); command have your text with not a single problem.

UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 23: ordinal not in range(128)

I was getting this error when executing in python3,I got the same program working by simply executing in python2

How to create checkbox inside dropdown?

Simply use bootstrap-multiselect where you can populate dropdown with multiselect option and many more feaatures.

For doc and tutorials you may visit below link

https://www.npmjs.com/package/bootstrap-multiselect

http://davidstutz.de/bootstrap-multiselect/

How do you programmatically set an attribute?

Usually, we define classes for this.

class XClass( object ):
   def __init__( self ):
       self.myAttr= None

x= XClass()
x.myAttr= 'magic'
x.myAttr

However, you can, to an extent, do this with the setattr and getattr built-in functions. However, they don't work on instances of object directly.

>>> a= object()
>>> setattr( a, 'hi', 'mom' )
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: 'object' object has no attribute 'hi'

They do, however, work on all kinds of simple classes.

class YClass( object ):
    pass

y= YClass()
setattr( y, 'myAttr', 'magic' )
y.myAttr

How to get the system uptime in Windows?

I use this little PowerShell snippet:

function Get-SystemUptime {
    $operatingSystem = Get-WmiObject Win32_OperatingSystem
    "$((Get-Date) - ([Management.ManagementDateTimeConverter]::ToDateTime($operatingSystem.LastBootUpTime)))"
}

which then yields something like the following:

PS> Get-SystemUptime
6.20:40:40.2625526

How to replace a string in multiple files in linux command line

Similar to Kaspar's answer but with the g flag to replace all the occurrences on a line.

find ./ -type f -exec sed -i 's/string1/string2/g' {} \;

For global case insensitive:

find ./ -type f -exec sed -i 's/string1/string2/gI' {} \;

Jquery click event not working after append method

Use on :

$('#registered_participants').on('click', '.new_participant_form', function() {

So that the click is delegated to any element in #registered_participants having the class new_participant_form, even if it's added after you bound the event handler.

How to open spss data files in excel?

I help develop the Colectica for Excel addin, which opens SPSS and Stata data files in Excel. This does not require ODBC configuration; it reads the file and then inserts the data and metadata into your worksheet.

The addin is downloadable from http://www.colectica.com/software/colecticaforexcel

Convert string (without any separator) to list

A python string is a list of characters. You can iterate over it right now!

justdigits = ""
for char in string:
    if char.isdigit():
        justdigits += str(char)

use std::fill to populate vector with increasing numbers

I know this is old question, but I am currently playing with library to handle exactly this problem. It requires c++14.

#include "htl.hpp"

htl::Token _;

std::vector<int> vec = _[0, _, 100];
// or
for (auto const e: _[0, _, 100]) { ... }

// supports also custom steps
// _[0, _%3, 100] == 0, 4, 7, 10, ...

Remove scroll bar track from ScrollView in Android

I'm a little confused why you are putting a WebView into a ScrollView in the first place. A WebView has it's own built-in scrolling system.

Regarding your actual question, if you want the Scrollbar to show up on top, you can use

view.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY) or   
android:scrollbarStyle="insideOverlay"

Use dynamic variable names in JavaScript

You can use the window object to get at it .

window['myVar']

window has a reference to all global variables and global functions you are using.

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

I would encourage you to see this youtube video which demonstrates the difference between C# bin and obj folders and also explains how we get the benefit of incremental/conditional compilation.

C# compilation is a two-step process, see the below diagram for more details:

  1. Compiling: In compiling phase individual C# code files are compiled into individual compiled units. These individual compiled code files go in the OBJ directory.
  2. Linking: In the linking phase these individual compiled code files are linked to create single unit DLL and EXE. This goes in the BIN directory.

C# bin vs obj folders

If you compare both bin and obj directory you will find greater number of files in the "obj" directory as it has individual compiled code files while "bin" has a single unit.

bin vs obj

Modulo operator with negative values

From ISO14882:2011(e) 5.6-4:

The binary / operator yields the quotient, and the binary % operator yields the remainder from the division of the first expression by the second. If the second operand of / or % is zero the behavior is undefined. For integral operands the / operator yields the algebraic quotient with any fractional part discarded; if the quotient a/b is representable in the type of the result, (a/b)*b + a%b is equal to a.

The rest is basic math:

(-7/3) => -2
-2 * 3 => -6
so a%b => -1

(7/-3) => -2
-2 * -3 => 6
so a%b => 1

Note that

If both operands are nonnegative then the remainder is nonnegative; if not, the sign of the remainder is implementation-defined.

from ISO14882:2003(e) is no longer present in ISO14882:2011(e)

Build error, This project references NuGet

This problem appeared for me when I was creating folders in the filesystem (not in my solution) and moved some projects around.

Turns out that the package paths are relative from the csproj files. So I had to change the "HintPath" of my references:

<Reference Include="EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL">
    <HintPath>..\packages\EntityFramework.6.1.3\lib\net45\EntityFramework.dll</HintPath>
    <Private>True</Private>
</Reference>

To:

<Reference Include="EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089, processorArchitecture=MSIL">
    <HintPath>..\..\packages\EntityFramework.6.1.3\lib\net45\EntityFramework.dll</HintPath>
    <Private>True</Private>
</Reference>

Notice the double "..\" in 'HintPath'.

I also had to change my error conditions, for example I had to change:

<Error Condition="!Exists('..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props'))" />

To:

<Error Condition="!Exists('..\..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props')" Text="$([System.String]::Format('$(ErrorText)', '..\..\packages\Microsoft.Net.Compilers.1.1.1\build\Microsoft.Net.Compilers.props'))" />

Again, notice the double "..\".

Retrieving data from a POST method in ASP.NET

The data from the request (content, inputs, files, querystring values) is all on this object HttpContext.Current.Request
To read the posted content

StreamReader reader = new StreamReader(HttpContext.Current.Request.InputStream);
string requestFromPost = reader.ReadToEnd();

To navigate through the all inputs

foreach (string key in HttpContext.Current.Request.Form.AllKeys)
{
   string value = HttpContext.Current.Request.Form[key];
}

Best way to get user GPS location in background in Android

You can archive it with a Service and Alarm Manager, but be careful with this, because if you setup a high priority you gonna drain the battery of the phone, in other hand, you really need notify the location every minute? This is because the only way to see a considerably change of the user location, it's traveling in a car or train. I only ask, because that gonna depend of you app and the requirement of the tracking.

JQuery Calculate Day Difference in 2 date textboxes

$("#edate").change(function(){

   var edate = new Date($('#edate').val());
   var sdate = new Date($('#sdate').val());
   
   days = (edate- sdate) / (1000 * 60 * 60 * 24);
   days=days+1;
   alert (days);
   $("#nod").val(days);
});

WindowsError: [Error 126] The specified module could not be found

NestedCaveats solution worked for me.

Imported my .dll files before importing torch and gpytorch, and all went smoothly.

So I just want to add that its not just importing pytorch but I can confirm that torch and gpytorch have this issue as well. I'd assume it covers any other torch-related libraries.

In AngularJS, what's the difference between ng-pristine and ng-dirty?

Both directives obviously serve the same purpose, and though it seems that the decision of the angular team to include both interfere with the DRY principle and adds to the payload of the page, it still is rather practical to have them both around. It is easier to style your input elements as you have both .ng-pristine and .ng-dirty available for styling in your css files. I guess this was the primary reason for adding both directives.

Docker error cannot delete docker container, conflict: unable to remove repository reference

There is a difference between docker images and docker containers. Check this SO Question.

In short, a container is a runnable instance of an image. which is why you cannot delete an image if there is a running container from that image. You just need to delete the container first.

docker ps -a                # Lists containers (and tells you which images they are spun from)

docker images               # Lists images 

docker rm <container_id>    # Removes a stopped container

docker rm -f <container_id> # Forces the removal of a running container (uses SIGKILL)

docker rmi <image_id>       # Removes an image 
                            # Will fail if there is a running instance of that image i.e. container

docker rmi -f <image_id>    # Forces removal of image even if it is referenced in multiple repositories, 
                            # i.e. same image id given multiple names/tags 
                            # Will still fail if there is a docker container referencing image

Update for Docker 1.13+ [Since Jan 2017]

In Docker 1.13, we regrouped every command to sit under the logical object it’s interacting with

Basically, above commands could also be rewritten, more clearly, as:

docker container ls -a
docker image ls
docker container rm <container_id>
docker image rm <image_id>

Also, if you want to remove EVERYTHING you could use:

docker system prune -a

WARNING! This will remove:

  • all stopped containers
  • all networks not used by at least one container
  • all unused images
  • all build cache

Execute an action when an item on the combobox is selected

this is how you do it with ActionLIstener

import java.awt.FlowLayout;
import java.awt.event.*;

import javax.swing.*;

public class MyWind extends JFrame{

    public MyWind() {
        initialize();
    }

    private void initialize() {
        setSize(300, 300);
        setLayout(new FlowLayout(FlowLayout.LEFT));
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTextField field = new JTextField();
        field.setSize(200, 50);
        field.setText("              ");

        JComboBox comboBox = new JComboBox();
        comboBox.setEditable(true);
        comboBox.addItem("item1");
        comboBox.addItem("item2");

        //
        // Create an ActionListener for the JComboBox component.
        //
        comboBox.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                //
                // Get the source of the component, which is our combo
                // box.
                //
                JComboBox comboBox = (JComboBox) event.getSource();

                Object selected = comboBox.getSelectedItem();
                if(selected.toString().equals("item1"))
                field.setText("30");
                else if(selected.toString().equals("item2"))
                    field.setText("40");

            }
        });
        getContentPane().add(comboBox);
        getContentPane().add(field);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new MyWind().setVisible(true);
            }
        });
    }
}

jquery toggle slide from left to right and back

Sliding from the right:

$('#example').animate({width:'toggle'},350);

Sliding to the left:

$('#example').toggle({ direction: "left" }, 1000);

How to show git log history (i.e., all the related commits) for a sub directory of a git repo?

You can use git log with the pathnames of the respective folders:

git log A B

The log will only show commits made in A and B. I usually throw in --stat to make things a little prettier, which helps for quick commit reviews.

How do I force "git pull" to overwrite local files?

An easier way would be to:

git checkout --theirs /path/to/file.extension
git pull origin master

This will override your local file with the file on git

Kotlin Error : Could not find org.jetbrains.kotlin:kotlin-stdlib-jre7:1.0.7

buildscript {
    **ext.kotlin_version = '1.1.1'**  //Add this line
    repositories {
        **jcenter()**                 //Add this line
        google()
    }
    dependencies {
//        classpath 'com.android.tools.build:gradle:3.0.1'
        classpath 'com.android.tools.build:gradle:3.1.0'

        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        **jcenter()**                 //Add this line
        google()
        maven { url "https://jitpack.io" }
    }
}

How do I change the data type for a column in MySQL?

If you want to change all columns of a certain type to another type, you can generate queries using a query like this:

select distinct concat('alter table ',
                       table_name,
                       ' modify ',
                       column_name,
                       ' <new datatype> ',
                       if(is_nullable = 'NO', ' NOT ', ''),
                       ' NULL;')
  from information_schema.columns
  where table_schema = '<your database>' 
    and column_type = '<old datatype>';

For instance, if you want to change columns from tinyint(4) to bit(1), run it like this:

select distinct concat('alter table ',
                       table_name,
                       ' modify ',
                       column_name,
                       ' bit(1) ',
                       if(is_nullable = 'NO', ' NOT ', ''),
                       ' NULL;')
  from information_schema.columns
  where table_schema = 'MyDatabase' 
    and column_type = 'tinyint(4)';

and get an output like this:

alter table table1 modify finished bit(1)  NOT  NULL;
alter table table2 modify canItBeTrue bit(1)  NOT  NULL;
alter table table3 modify canBeNull bit(1)  NULL;

!! Does not keep unique constraints, but should be easily fixed with another if-parameter to concat. I'll leave it up to the reader to implement that if needed..

How to create an alert message in jsp page after submit process is complete

You can also create a new jsp file sayng that form is submited and in your main action file just write its file name

Eg. Your form is submited is in a file succes.jsp Then your action file will have

Request.sendRedirect("success.jsp")

Classes cannot be accessed from outside package

Note that the default when you make a class is not public as far as packages are considered. Make sure that you actually write public class [MyClass] { when defining your class. I've made this mistake more times than I care to admit.

Change Default branch in gitlab

in the GitLab Enterprise Edition 12.2.0-pre you have to use following: Setting ? Repository ? Default Branch ( expand it) and change the default branch Here

Object passed as parameter to another class, by value or reference?

Assuming someTestObj is a class and not a struct, the object is passed by reference, which means that both obj and someTestObj refer to the same object. E.g. changing name in one will change it in the other. However, unlike if you passed it using the ref keyword, setting obj = somethingElse will not change someTestObj.

How to force garbage collector to run?

I think that .Net Framework does this automatically but just in case. First, make sure to select what you want to erase, and then call the garbage collector:

randomClass object1 = new randomClass
...
...
// Give a null value to the code you want to delete
object1 = null;
// Then call the garbage collector to erase what you gave the null value
GC.Collect();

I think that's it.. Hope I help someone.

How to filter (key, value) with ng-repeat in AngularJs?

My solution would be create custom filter and use it:

app.filter('with', function() {
  return function(items, field) {
        var result = {};
        angular.forEach(items, function(value, key) {
            if (!value.hasOwnProperty(field)) {
                result[key] = value;
            }
        });
        return result;
    };
});

And in html:

 <div ng-repeat="(k,v) in items | with:'secId'">
        {{k}} {{v.pos}}
 </div>

Display HTML snippets in HTML

Actually there is a way to do this. It has limitation (one), but is 100% standard, not deprecated (like xmp), and works.

And it's trivial. Here it is:

<div id="mydoc-src" style="display: none;">
LlNnlljn77fggggkk77csJJK8bbJBKJBkjjjjbbbJJLJLLJo
<!--
YOUR CODE HERE.
    <script src="WidgetsLib/all.js"></script>
    ^^ This is a text, no side effects trying to load it.
-->
LlNnlljn77fggggkk77csJJK8bbJBKJBkjjjjbbbJJLJLLJo
</div>

Please let me explain. First of all, ordinary HTML comment does the job, to prevent whole block be interpreted. You can easily add in it any tags, all of them will be ignored. Ignored from interpretation, but still available via innerHTML! So what is left, is to get the contents, and filter the preceding and trailing comment tokens.

Except (remember - the limitation) you can't put there HTML comments inside, since (at least in my Chrome) nesting of them is not supported, and very first '-->' will end the show.

Well, it is a nasty little limitation, but in certain cases it's not a problem at all, if your text is free of HTML comments. And, it's easier to escape one construct, then a whole bunch of them.

Now, what is that weird LlNnlljn77fggggkk77csJJK8bbJBKJBkjjjjbbbJJLJLLJo string? It's a random string, like a hash, unlikely to be used in the block, and used for? Here's the context, why I have used it. In my case, I took the contents of one DIV, then processed it with Showdown markdown, and then the output assigned into another div. The idea was, to write markdown inline in the HTML file, and just open in a browser and it would transform on the load on-the-fly. So, in my case, <!-- became transformed to <p><!--</p>, the comment properly escaped. It worked, but polluted the screen. So, to easily remove it with regex, the random string was used. Here's the code:

    var converter = new showdown.Converter();
    converter.setOption('simplifiedAutoLink', true);
    converter.setOption('tables', true);
    converter.setOption('tasklists', true);
    var src = document.getElementById("mydoc-src");
    var res = document.getElementById("mydoc-res");
    res.innerHTML = converter.makeHtml(src.innerHTML)
            .replace(/<p>.{0,10}LlNnlljn77fggggkk77csJJK8bbJBKJBkjjjjbbbJJLJLLJo.{0,10}<\/p>/g, "");
    src.innerHTML = '';

And it works.

If somebody is interested, this article is written using this technique. Feel free to download, and look inside the HTML file.

It depends what you are using it for. Is it user input? Then use <textarea>, and escape everything. In my case, and probably it's your case too, I simply used comments, and it does the job.

If you don't use markdown, and just want to get it as is from a tag, then it's even simpler:

<div id="mydoc-src" style="display: none;">
<!--
YOUR CODE HERE.
    <script src="WidgetsLib/all.js"></script>
    ^^ This is a text, no side effects trying to load it.
-->
</div>

and JavaScript code to get it:

    var src = document.getElementById("mydoc-src");
    var YOUR_CODE = src.innerHTML.replace(/(<!--|-->)/g, "");

ProcessBuilder: Forwarding stdout and stderr of started processes without blocking the main thread

It's as simple as following:

    File logFile = new File(...);
    ProcessBuilder pb = new ProcessBuilder()
        .command("somecommand", "arg1", "arg2")
    processBuilder.redirectErrorStream(true);
    processBuilder.redirectOutput(logFile);

by .redirectErrorStream(true) you tell process to merge error and output stream and then by .redirectOutput(file) you redirect merged output to a file.

Update:

I did manage to do this as follows:

public static void main(String[] args) {
    // Async part
    Runnable r = () -> {
        ProcessBuilder pb = new ProcessBuilder().command("...");
        // Merge System.err and System.out
        pb.redirectErrorStream(true);
        // Inherit System.out as redirect output stream
        pb.redirectOutput(ProcessBuilder.Redirect.INHERIT);
        try {
            pb.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    };
    new Thread(r, "asyncOut").start();
    // here goes your main part
}

Now you're able to see both outputs from main and asyncOut threads in System.out

What are alternatives to ExtJS?

Nothing compares to in terms of community size and presence on StackOverflow. Despite previous controversy, Ext JS now has a GPLv3 open source license. Its learning curve is long, but it can be quite rewarding once learned. Ext JS lacks a Material Design theme, and the team has repeatedly refused to release the source code on GitHub. For mobile, one must use the separate Sencha Touch library.

Have in mind also that,

large JavaScript libraries, such as YUI, have been receiving less attention from the community. Many developers today look at large JavaScript libraries as walled gardens they don’t want to be locked into.

-- Announcement of YUI development being ceased

That said, below are a number of Ext JS alternatives currently available.

Leading client widget libraries

  1. Blueprint is a React-based UI toolkit developed by big data analytics company Palantir in TypeScript, and "optimized for building complex data-dense interfaces for desktop applications". Actively developed on GitHub as of May 2019, with comprehensive documentation. Components range from simple (chips, toast, icons) to complex (tree, data table, tag input with autocomplete, date range picker. No accordion or resizer.

    Blueprint targets modern browsers (Chrome, Firefox, Safari, IE 11, and Microsoft Edge) and is licensed under a modified Apache license.

    Sandbox / demoGitHubDocs

  2. Webix - an advanced, easy to learn, mobile-friendly, responsive and rich free&open source JavaScript UI components library. Webix spun off from DHTMLX Touch (a project with 8 years of development behind it - see below) and went on to become a standalone UI components framework. The GPL3 edition allows commercial use and lets non-GPL applications using Webix keep their license, e.g. MIT, via a license exemption for FLOSS. Webix has 55 UI widgets, including trees, grids, treegrids and charts. Funding comes from a commercial edition with some advanced widgets (Pivot, Scheduler, Kanban, org chart etc.). Webix has an extensive list of free and commercial widgets, and integrates with most popular frameworks (React, Vue, Meteor, etc) and UI components.

    Webix

    Skins look modern, and include a Material Design theme. The Touch theme also looks quite Material Design-ish. See also the Skin Builder.

    Minimal GitHub presence, but includes the library code, and the documentation (which still needs major improvements). Webix suffers from a having a small team and a lack of marketing. However, they have been responsive to user feedback, both on GitHub and on their forum.

    The library was lean (128Kb gzip+minified for all 55 widgets as of ~2015), faster than ExtJS, dojo and others, and the design is pleasant-looking. The current version of Webix (v6, as of Nov 2018) got heavier (400 - 676kB minified but NOT gzipped).

    The demos on Webix.com look and function great. The developer, XB Software, uses Webix in solutions they build for paying customers, so there's likely a good, funded future ahead of it.

    Webix aims for backwards compatibility down to IE8, and as a result carries some technical debt.

    WikipediaGitHubPlayground/sandboxAdmin dashboard demoDemosWidget samples

  3. react-md - MIT-licensed Material Design UI components library for React. Responsive, accessible. Implements components from simple (buttons, cards) to complex (sortable tables, autocomplete, tags input, calendars). One lead author, ~1900 GitHub stars.

  4. - jQuery-based UI toolkit with 40+ basic open-source widgets, plus commercial professional widgets (grids, trees, charts etc.). Responsive&mobile support. Works with Bootstrap and AngularJS. Modern, with Material Design themes. The documentation is available on GitHub, which has enabled numerous contributions from users (4500+ commits, 500+ PRs as of Jan 2015).

    enter image description here

    Well-supported commercially, claiming millions of developers, and part of a large family of developer tools. Telerik has received many accolades, is a multi-national company (Bulgaria, US), was acquired by Progress Software, and is a thought leader.

    A Kendo UI Professional developer license costs $700 and posting access to most forums is conditioned upon having a license or being in the trial period.

    [Wikipedia] • GitHub/TelerikDemosPlaygroundTools

  5. OpenUI5 - jQuery-based UI framework with 180 widgets, Apache 2.0-licensed and fully-open sourced and funded by German software giant SAP SE.

    OpenUI5

    The community is much larger than that of Webix, SAP is hiring developers to grow OpenUI5, and they presented OpenUI5 at OSCON 2014.

    The desktop themes are rather lackluster, but the Fiori design for web and mobile looks clean and neat.

    WikipediaGitHubMobile-first controls demosDesktop controls demosSO

  6. DHTMLX - JavaScript library for building rich Web and Mobile apps. Looks most like ExtJS - check the demos. Has been developed since 2005 but still looks modern. All components except TreeGrid are available under GPLv2 but advanced features for many components are only available in the commercial PRO edition - see for example the tree. Claims to be used by many Fortune 500 companies.

    DHTMLX

    Minimal presence on GitHub (the main library code is missing) and StackOverflow but active forum. The documentation is not available on GitHub, which makes it difficult to improve by the community.

  7. Polymer, a Web Components polyfill, plus Polymer Paper, Google's implementation of the Material design. Aimed at web and mobile apps. Doesn't have advanced widgets like trees or even grids but the controls it provides are mobile-first and responsive. Used by many big players, e.g. IBM or USA Today.

    Polymer Paper Elements

  8. Ant Design claims it is "a design language for background applications", influenced by "nature" and helping designers "create low-entropy atmosphere for developer team". That's probably a poor translation from Chinese for "UI components for enterprise web applications". It's a React UI library written in TypeScript, with many components, from simple (buttons, cards) to advanced (autocomplete, calendar, tag input, table).

    The project was born in China, is popular with Chinese companies, and parts of the documentation are available only in Chinese. Quite popular on GitHub, yet it makes the mistake of splitting the community into Chinese and English chat rooms. The design looks Material-ish, but fonts are small and the information looks lost in a see of whitespace.

  9. PrimeUI - collection of 45+ rich widgets based on jQuery UI. Apache 2.0 license. Small GitHub community. 35 premium themes available.

  10. qooxdoo - "a universal JavaScript framework with a coherent set of individual components", developed and funded by German hosting provider 1&1 (see the contributors, one of the world's largest hosting companies. GPL/EPL (a business-friendly license).

    Mobile themes look modern but desktop themes look old (gradients).

    Qooxdoo

    WikipediaGitHubWeb/Mobile/Desktop demosWidgets Demo browserWidget browserSOPlaygroundCommunity

  11. jQuery UI - easy to pick up; looks a bit dated; lacks advanced widgets. Of course, you can combine it with independent widgets for particular needs, e.g. trees or other UI components, but the same can be said for any other framework.

  12. + Angular UI. While Angular is backed by Google, it's being radically revamped in the upcoming 2.0 version, and "users will need to get to grips with a new kind of architecture. It's also been confirmed that there will be no migration path from Angular 1.X to 2.0". Moreover, the consensus seems to be that Angular 2 won't really be ready for use until a year or two from now. Angular UI has relatively few widgets (no trees, for example).

  13. DojoToolkit and their powerful Dijit set of widgets. Completely open-sourced and actively developed on GitHub, but development is now (Nov 2018) focused on the new dojo.io framework, which has very few basic widgets. BSD/AFL license. Development started in 2004 and the Dojo Foundation is being sponsored by IBM, Google, and others - see Wikipedia. 7500 questions here on SO.

    Dojo Dijit

    Themes look desktop-oriented and dated - see the theme tester in dijit. The official theme previewer is broken and only shows "Claro". A Bootstrap theme exists, which looks a lot like Bootstrap, but doesn't use Bootstrap classes. In Jan 2015, I started a thread on building a Material Design theme for Dojo, which got quite popular within the first hours. However, there are questions regarding building that theme for the current Dojo 1.10 vs. the next Dojo 2.0. The response to that thread shows an active and wide community, covering many time zones.

    Unfortunately, Dojo has fallen out of popularity and fewer companies appear to use it, despite having (had?) a strong foothold in the enterprise world. In 2009-2012, its learning curve was steep and the documentation needed improvements; while the documentation has substantially improved, it's unclear how easy it is to pick up Dojo nowadays.

    With a Material Design theme, Dojo (2.0?) might be the killer UI components framework.

    WikipediaGitHubThemesDemosDesktop widgetsSO

  14. Enyo - front-end library aimed at mobile and TV apps (e.g. large touch-friendly controls). Developed by LG Electronix and Apache-licensed on GitHub.

  15. The radical Cappuccino - Objective-J (a superset of JavaScript) instead of HTML+CSS+DOM

  16. Mochaui, MooTools UI Library User Interface Library. <300 GitHub stars.

  17. CrossUI - cross-browser JS framework to develop and package the exactly same code and UI into Web Apps, Native Desktop Apps (Windows, OS X, Linux) and Mobile Apps (iOS, Android, Windows Phone, BlackBerry). Open sourced LGPL3. Featured RAD tool (form builder etc.). The UI looks desktop-, not web-oriented. Actively developed, small community. No presence on GitHub.

  18. ZinoUI - simple widgets. The DataTable, for instance, doesn't even support sorting.

  19. Wijmo - good-looking commercial widgets, with old (jQuery UI) widgets open-sourced on GitHub (their development stopped in 2013). Developed by ComponentOne, a division of GrapeCity. See Wijmo Complete vs. Open.

  20. CxJS - commercial JS framework based on React, Babel and webpack offering form elements, form validation, advanced grid control, navigational elements, tooltips, overlays, charts, routing, layout support, themes, culture dependent formatting and more.

CxJS

Widgets - Demo Apps - Examples - GitHub

Full-stack frameworks

  1. SproutCore - developed by Apple for web applications with native performance, handling large data sets on the client. Powers iCloud.com. Not intended for widgets.

  2. Wakanda: aimed at business/enterprise web apps - see What is Wakanda?. Architecture:

  3. Servoy - "a cross platform frontend development and deployment environment for SQL databases". Boasts a "full WYSIWIG (What You See Is What You Get) UI designer for HTML5 with built-in data-binding to back-end services", responsive design, support for HTML6 Web Components, Websockets and mobile platforms. Written in Java and generates JavaScript code using various JavaBeans.

  4. SmartClient/SmartGWT - mobile and cross-browser HTML5 UI components combined with a Java server. Aimed at building powerful business apps - see demos.

  5. Vaadin - full-stack Java/GWT + JavaScript/HTML3 web app framework

  6. Backbase - portal software

  7. Shiny - front-end library on top R, with visualization, layout and control widgets

  8. ZKOSS: Java+jQuery+Bootstrap framework for building enterprise web and mobile apps.

CSS libraries + minimal widgets

These libraries don't implement complex widgets such as tables with sorting/filtering, autocompletes, or trees.

  1. Bootstrap

  2. Foundation for Apps - responsive front-end framework on top of AngularJS; more of a grid/layout/navigation library

  3. UI Kit - similar to Bootstrap, with fewer widgets, but with official off-canvas.

Libraries using HTML Canvas

Using the canvas elements allows for complete control over the UI, and great cross-browser compatibility, but comes at the cost of missing native browser functionality, e.g. page search via Ctrl/Cmd+F.

  1. Zebra - demos

No longer developed as of Dec 2014

  1. Yahoo! User Interface - YUI, launched in 2005, but no longer maintained by the core contributors - see the announcement, which highlights reasons why large UI widget libraries are perceived as walled gardens that developers don't want to be locked into.
  2. echo3, GitHub. Supports writing either server-side Java applications that don't require developer knowledge of HTML, HTTP, or JavaScript, or client-side JavaScript-based applications do not require a server, but can communicate with one via AJAX. Last update: July 2013.
  3. ampleSDK
  4. Simpler widgets livepipe.net
  5. JxLib
  6. rialto
  7. Simple UI kit
  8. Prototype-ui

Other lists

Can I run a 64-bit VMware image on a 32-bit machine?

VMware? No. However, QEMU has an x86_64 system target that you can use. You likely won't be able to use a VMware image directly (IIRC, there's no conversion tool), but you can install the OS and such yourself and work inside it. QEMU can be a bit of a PITA to get up and running, but it tends to work quite nicely.

How to get data out of a Node.js http get request

from learnyounode:

var http = require('http')  

http.get(options, function (response) {  
  response.setEncoding('utf8')  
  response.on('data', console.log)  
  response.on('error', console.error)  
})

'options' is the host/path variable

Is it possible to force Excel recognize UTF-8 CSV files automatically?

Yes, this is possible. As previously noted by multiple users, there seems to be a problem with excel reading the correct Byte Order Mark when the file is encoded in UTF-8. With UTF-16 it does not seem to have a problem, so it is endemic to UTF-8. The solution I use for this is adding the BOM, TWICE. For this I execute the following sed command twice:

sed -I '1s/^/\xef\xbb\xbf/' *.csv

, where the wildcard can be replaced with any file name. However, this leads to a mutation of the sep= at the beginning of the .csv file. The .csv file will then open normally in excel, but with an extra row with "sep=" in the first cell. The "sep=" can also be removed in the source .csv itself, but when opening the file with VBA the delimiter should be specified:

Workbooks.Open(name, Format:=6, Delimiter:=";", Local:=True)

Format 6 is the .csv format. Set Local to true, in case there are dates in the file. If Local is not set to true the dates will be Americanized, which in some cases will corrupt the .csv format.

Python TypeError: not enough arguments for format string

You need to put the format arguments into a tuple (add parentheses):

instr = "'%s', '%s', '%d', '%s', '%s', '%s', '%s'" % (softname, procversion, int(percent), exe, description, company, procurl)

What you currently have is equivalent to the following:

intstr = ("'%s', '%s', '%d', '%s', '%s', '%s', '%s'" % softname), procversion, int(percent), exe, description, company, procurl

Example:

>>> "%s %s" % 'hello', 'world'
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: not enough arguments for format string
>>> "%s %s" % ('hello', 'world')
'hello world'

How to keep footer at bottom of screen

You could use position:fixed; to bottom.

eg:

#footer{
 position:fixed;
 bottom:0;
 left:0;
}

Update row values where certain condition is met in pandas

You can do the same with .ix, like this:

In [1]: df = pd.DataFrame(np.random.randn(5,4), columns=list('abcd'))

In [2]: df
Out[2]: 
          a         b         c         d
0 -0.323772  0.839542  0.173414 -1.341793
1 -1.001287  0.676910  0.465536  0.229544
2  0.963484 -0.905302 -0.435821  1.934512
3  0.266113 -0.034305 -0.110272 -0.720599
4 -0.522134 -0.913792  1.862832  0.314315

In [3]: df.ix[df.a>0, ['b','c']] = 0

In [4]: df
Out[4]: 
          a         b         c         d
0 -0.323772  0.839542  0.173414 -1.341793
1 -1.001287  0.676910  0.465536  0.229544
2  0.963484  0.000000  0.000000  1.934512
3  0.266113  0.000000  0.000000 -0.720599
4 -0.522134 -0.913792  1.862832  0.314315

EDIT

After the extra information, the following will return all columns - where some condition is met - with halved values:

>> condition = df.a > 0
>> df[condition][[i for i in df.columns.values if i not in ['a']]].apply(lambda x: x/2)

I hope this helps!

PHP Multidimensional Array Searching (Find key by specific value)

Very simple:

function myfunction($products, $field, $value)
{
   foreach($products as $key => $product)
   {
      if ( $product[$field] === $value )
         return $key;
   }
   return false;
}

How to copy data to clipboard in C#

On ASP.net web forms use in the @page AspCompat="true", add the system.windows.forms to you project. At your web.config add:

  <appSettings>
    <add key="aspnet:UseTaskFriendlySynchronizationContext" value="false" />
  </appSettings>

Then you can use:

Clipboard.SetText(CreateDescription());

Bug? #1146 - Table 'xxx.xxxxx' doesn't exist

Column names must be unique in the table. You cannot have two columns named asd in the same table.

How to convert a selection to lowercase or uppercase in Sublime Text

For Windows OS

For Uppercase CTRL + K + U

For Lowercase CTRL + K + L

Get the ID of a drawable in ImageView

I recently run into the same problem. I solved it by implementing my own ImageView class.

Here is my Kotlin implementation:

class MyImageView(context: Context): ImageView(context) {
    private var currentDrawableId: Int? = null

    override fun setImageResource(resId: Int) {
        super.setImageResource(resId)
        currentDrawableId = resId
    }

    fun getDrawableId() {
        return currentDrawableId
    }

    fun compareCurrentDrawable(toDrawableId: Int?): Boolean {
        if (toDrawableId == null || currentDrawableId != toDrawableId) {
            return false
        }

        return true
    }

}

Android: How to create a Dialog without a title?

Use below code before setcontentview :-

    Dialog dialog = new Dialog(this);
    dialog.requestWindowFeature(Window.FEATURE_NO_TITLE); 
    dialog.setContentView(R.layout.custom_dialog);

Note: You must have above code, in same order and line. requestWindowFeature must be before the setContentView line.

how to check if string contains '+' character

Why not just:

int plusIndex = s.indexOf("+");
if (plusIndex != -1) {
    String before = s.substring(0, plusIndex);
    // Use before
}

It's not really clear why your original version didn't work, but then you didn't say what actually happened. If you want to split not using regular expressions, I'd personally use Guava:

Iterable<String> bits = Splitter.on('+').split(s);
String firstPart = Iterables.getFirst(bits, "");

If you're going to use split (either the built-in version or Guava) you don't need to check whether it contains + first - if it doesn't there'll only be one result anyway. Obviously there's a question of efficiency, but it's simpler code:

// Calling split unconditionally
String[] parts = s.split("\\+");
s = parts[0];

Note that writing String[] parts is preferred over String parts[] - it's much more idiomatic Java code.

HTTP Status 500 - Error instantiating servlet class pkg.coreServlet

The servlet class should be in the WEB-INF/classes not WEB-INF/src.

How to change a css class style through Javascript?

You may also be interested in modifying it using jQuery: http://api.jquery.com/category/css/

how to use LIKE with column name

For SQLLite you will need to concat the strings

select * from list1 l, list2 ll 
WHERE l.name like "%"||ll.alias||"%";

Zero-pad digits in string

There's also str_pad

<?php
$input = "Alien";
echo str_pad($input, 10);                      // produces "Alien     "
echo str_pad($input, 10, "-=", STR_PAD_LEFT);  // produces "-=-=-Alien"
echo str_pad($input, 10, "_", STR_PAD_BOTH);   // produces "__Alien___"
echo str_pad($input, 6 , "___");               // produces "Alien_"
?>

Remove NA values from a vector

The na.omit function is what a lot of the regression routines use internally:

vec <- 1:1000
vec[runif(200, 1, 1000)] <- NA
max(vec)
#[1] NA
max( na.omit(vec) )
#[1] 1000

Android SDK Manager Not Installing Components

For Android Studio, selecting "Run As Administrator" while starting Android Studio helps.

How to open a website when a Button is clicked in Android application?

You can wrap the buttons in anchors that href to the appropriate website.

<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>
<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>
<a href="http://www.stackoverflow.com">
  <input type="button" value="Button" />
</a>

When the user clicks the button (input) they are directed to the destination specified in the href property of the anchor.

Edit: Oops, I didn't read "Eclipse" in the question title. My mistake.

Converting Integers to Roman Numerals - Java

I think if you study the theory of roman numerals carefully you don't require mappings for numbers 4,9,40 etc because the theory tells us if the roman numeral is IV = 5-1 = 4, hence when the prefix is smaller than the succeeding number in that case you have to subtract the former number from the succeeding number to get the actual value and this is what I have incorporated into my code for the problem, take a look and point out any mistakes if necessary, I followed this table to devise my logic - http://literacy.kent.edu/Minigrants/Cinci/romanchart.htm

import java.util.Set;
import java.io.File;
import java.util.HashMap;
import java.util.HashSet;
import java.io.FileReader;
import java.io.IOException;
import java.io.BufferedReader;

public class RomanStringToIntegerConversion {
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in)));
        String[] romanString = br.readLine().split("");

        HashMap<String, Integer> romanToIntegerMap = new HashMap<String, Integer>();
        romanToIntegerMap.put("I", 1);
        romanToIntegerMap.put("V", 5);
        romanToIntegerMap.put("X", 10);
        romanToIntegerMap.put("L", 50);
        romanToIntegerMap.put("C", 100);
        romanToIntegerMap.put("D", 500);
        romanToIntegerMap.put("M", 1000);

        int numLength = romanString.length;
        Set<Integer> lessIndices = new HashSet<Integer>();

        for(int i = 0; i < numLength; ++i){
            if(i+1 < numLength){
                if(romanToIntegerMap.get(romanString[i]) < romanToIntegerMap.get(romanString[i+1]))
                    lessIndices.add(i);
            }
        }

        int num = 0;
        for(int i = 0; i < numLength;){
            if(!lessIndices.contains(i)){
                num = num + romanToIntegerMap.get(romanString[i]);
                ++i;
            }
            else{
                num = num + romanToIntegerMap.get(romanString[i+1]) - romanToIntegerMap.get(romanString[i]);
                i+=2;
            }
        }
        System.out.println("The integer representation of the roman numeral is : " + num);
    }
}

Visual Studio opens the default browser instead of Internet Explorer

Also may be helpful for ASP.NET MVC:

In an MVC app, you have to right-click on Default.aspx, which is the only ‘real’ web page in that solution. The default page displays ‘Browse with…’

From http://avaricesoft.wordpress.com/2008/08/04/...

Convert a string date into datetime in Oracle

Hey I had the same problem. I tried to convert '2017-02-20 12:15:32' varchar to a date with TO_DATE('2017-02-20 12:15:32','YYYY-MM-DD HH24:MI:SS') and all I received was 2017-02-20 the time disappeared

My solution was to use TO_TIMESTAMP('2017-02-20 12:15:32','YYYY-MM-DD HH24:MI:SS') now the time doesn't disappear.

Checkboxes in web pages – how to make them bigger?

Pure modern 2020 CSS only decision, without blurry scaling or non-handy transforming. And with tick! =)

Works nice in Firefox and Chromium-based browsers.

So, you can rule your checkboxes purely ADAPTIVE, just by setting parent block's font-height and it will grow with text!

_x000D_
_x000D_
input[type='checkbox'] {_x000D_
  -moz-appearance: none;_x000D_
  -webkit-appearance: none;_x000D_
  appearance: none;_x000D_
  vertical-align: middle;_x000D_
  outline: none;_x000D_
  font-size: inherit;_x000D_
  cursor: pointer;_x000D_
  width: 1.0em;_x000D_
  height: 1.0em;_x000D_
  background: white;_x000D_
  border-radius: 0.25em;_x000D_
  border: 0.125em solid #555;_x000D_
  position: relative;_x000D_
}_x000D_
_x000D_
input[type='checkbox']:checked {_x000D_
  background: #adf;_x000D_
}_x000D_
_x000D_
input[type='checkbox']:checked:after {_x000D_
  content: "?";_x000D_
  position: absolute;_x000D_
  font-size: 90%;_x000D_
  left: 0.0625em;_x000D_
  top: -0.25em;_x000D_
}
_x000D_
<label for="check1"><input type="checkbox" id="check1" checked="checked" /> checkbox one</label>_x000D_
<label for="check2"><input type="checkbox" id="check2" /> another checkbox</label>
_x000D_
_x000D_
_x000D_

Setting POST variable without using form

If you want to set $_POST['text'] to another value, why not use:

$_POST['text'] = $var;

on next.php?

Java generics - get class?

Short answer: You can't.

Long answer:

Due to the way generics is implemented in Java, the generic type T is not kept at runtime. Still, you can use a private data member:

public class Foo<T> 
{
    private Class<T> type;

    public Foo(Class<T> type) { this.type = type; } 
}

Usage example:

Foo<Integer> test = new Foo<Integer>(Integer.class);

Typescript: How to define type for a function callback (as any function type, not universal any) used in a method parameter

The global type Function serves this purpose.

Additionally, if you intend to invoke this callback with 0 arguments and will ignore its return value, the type () => void matches all functions taking no arguments.


Update with details and improvements.

The answer and question here has way too many updoots not to mention the only-slightly more complex yet best-practice method:

Solution to your question

interface Easy_Fix_Solution {
    title: string;
    callback: Function;
}

NOTE: Please do not use Function as you most likely do not want any callback function. It's okay to be a little specific.

Improvement to that solution

interface Safer_Easy_Fix {
    title: string;
    callback: () => void;
}
interface Alternate_Syntax_4_Safer_Easy_Fix {
    title: string;
    callback(): void;
}

NOTE: The original author is correct, accepting no arguments and returning void is better.. it's much safer, it tells the consumer of your interface that you will not be doing anything with their return value, and that you will not be passing them any parameters.

And better yet Use generics. This interface would also work for the same () => void function types mentioned before.

interface Better_still_safe_but_way_more_flexible_fix {
    title: string;
    callback: <T = unknown, R = unknown>(args?: T) => R;
}
interface Alternate_Syntax_4_Better_still_safe_but_way_more_flexible_fix {
    title: string;
    callback<T = unknown, R = unknown>(args?: T): R;
}

NOTE: If you aren't 100% sure about the callback signature right now, please choose the void option above, or this generic option if you think you may extend functionality going forward. Callbacks usually receive some arguments of some sort, and sometimes the callback orchestrator even does something with the return value.

And a slightly more advanced usecase you shouldn't use unless you need it

This allows any number of arguments, of any type in T.

More details here.

interface Alternate_Syntax_4_Advanced {
    title: string;
    callback<T extends unknown[], R = unknown>(...args?: T): R;
}

How to convert AAR to JAR

For those, who want to do it automatically, I have wrote a little two-lines bash script which does next two things:

  1. Looks for all *.aar files and extracts classes.jar from them
  2. Renames extracted classes.jar to be like the aar but with a new extension

    find . -name '*.aar' -exec sh -c 'unzip -d `dirname {}` {} classes.jar' \;
    find . -name '*.aar' -exec sh -c 'mv `dirname {}`/classes.jar `echo {} | sed s/aar/jar/g`' \;
    

That's it!

Finding the id of a parent div using Jquery

This can be easily done by doing:

$(this).closest('table').attr('id');

You attach this to any object inside a table and it will return you the id of that table.

How do I reset a sequence in Oracle?

Stored procedure that worked for me

create or replace
procedure reset_sequence( p_seq_name in varchar2, tablename in varchar2 )
is
    l_val number;
    maxvalueid number;
begin
    execute immediate 'select ' || p_seq_name || '.nextval from dual' INTO l_val;
    execute immediate 'select max(id) from ' || tablename INTO maxvalueid;
    execute immediate 'alter sequence ' || p_seq_name || ' increment by -' || l_val || ' minvalue 0';
    execute immediate 'select ' || p_seq_name || '.nextval from dual' INTO l_val;
    execute immediate 'alter sequence ' || p_seq_name || ' increment by '|| maxvalueid ||' minvalue 0';  
    execute immediate 'select ' || p_seq_name || '.nextval from dual' INTO l_val;
    execute immediate 'alter sequence ' || p_seq_name || ' increment by 1 minvalue 0';
end;

How to use the stored procedure:

execute reset_sequence('company_sequence','company');

Send raw ZPL to Zebra printer via USB

Visual Studio C# solution (found at http://support.microsoft.com/kb/322091)

Step 1.) Create class RawPrinterHelper...

using System;
using System.IO;
using System.Runtime.InteropServices;

public class RawPrinterHelper
{
    // Structure and API declarions:
    [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
    public class DOCINFOA
    {
        [MarshalAs(UnmanagedType.LPStr)]
        public string pDocName;
        [MarshalAs(UnmanagedType.LPStr)]
        public string pOutputFile;
        [MarshalAs(UnmanagedType.LPStr)]
        public string pDataType;
    }
    [DllImport("winspool.Drv", EntryPoint = "OpenPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPStr)] string szPrinter, out IntPtr hPrinter, IntPtr pd);

    [DllImport("winspool.Drv", EntryPoint = "ClosePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool ClosePrinter(IntPtr hPrinter);

    [DllImport("winspool.Drv", EntryPoint = "StartDocPrinterA", SetLastError = true, CharSet = CharSet.Ansi, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool StartDocPrinter(IntPtr hPrinter, Int32 level, [In, MarshalAs(UnmanagedType.LPStruct)] DOCINFOA di);

    [DllImport("winspool.Drv", EntryPoint = "EndDocPrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool EndDocPrinter(IntPtr hPrinter);

    [DllImport("winspool.Drv", EntryPoint = "StartPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool StartPagePrinter(IntPtr hPrinter);

    [DllImport("winspool.Drv", EntryPoint = "EndPagePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool EndPagePrinter(IntPtr hPrinter);

    [DllImport("winspool.Drv", EntryPoint = "WritePrinter", SetLastError = true, ExactSpelling = true, CallingConvention = CallingConvention.StdCall)]
    public static extern bool WritePrinter(IntPtr hPrinter, IntPtr pBytes, Int32 dwCount, out Int32 dwWritten);

    // SendBytesToPrinter()
    // When the function is given a printer name and an unmanaged array
    // of bytes, the function sends those bytes to the print queue.
    // Returns true on success, false on failure.
    public static bool SendBytesToPrinter(string szPrinterName, IntPtr pBytes, Int32 dwCount)
    {
        Int32 dwError = 0, dwWritten = 0;
        IntPtr hPrinter = new IntPtr(0);
        DOCINFOA di = new DOCINFOA();
        bool bSuccess = false; // Assume failure unless you specifically succeed.

        di.pDocName = "My C#.NET RAW Document";
        di.pDataType = "RAW";

        // Open the printer.
        if (OpenPrinter(szPrinterName.Normalize(), out hPrinter, IntPtr.Zero))
        {
            // Start a document.
            if (StartDocPrinter(hPrinter, 1, di))
            {
                // Start a page.
                if (StartPagePrinter(hPrinter))
                {
                    // Write your bytes.
                    bSuccess = WritePrinter(hPrinter, pBytes, dwCount, out dwWritten);
                    EndPagePrinter(hPrinter);
                }
                EndDocPrinter(hPrinter);
            }
            ClosePrinter(hPrinter);
        }
        // If you did not succeed, GetLastError may give more information
        // about why not.
        if (bSuccess == false)
        {
            dwError = Marshal.GetLastWin32Error();
        }
        return bSuccess;
    }

    public static bool SendFileToPrinter(string szPrinterName, string szFileName)
    {
        // Open the file.
        FileStream fs = new FileStream(szFileName, FileMode.Open);
        // Create a BinaryReader on the file.
        BinaryReader br = new BinaryReader(fs);
        // Dim an array of bytes big enough to hold the file's contents.
        Byte[] bytes = new Byte[fs.Length];
        bool bSuccess = false;
        // Your unmanaged pointer.
        IntPtr pUnmanagedBytes = new IntPtr(0);
        int nLength;

        nLength = Convert.ToInt32(fs.Length);
        // Read the contents of the file into the array.
        bytes = br.ReadBytes(nLength);
        // Allocate some unmanaged memory for those bytes.
        pUnmanagedBytes = Marshal.AllocCoTaskMem(nLength);
        // Copy the managed byte array into the unmanaged array.
        Marshal.Copy(bytes, 0, pUnmanagedBytes, nLength);
        // Send the unmanaged bytes to the printer.
        bSuccess = SendBytesToPrinter(szPrinterName, pUnmanagedBytes, nLength);
        // Free the unmanaged memory that you allocated earlier.
        Marshal.FreeCoTaskMem(pUnmanagedBytes);
        return bSuccess;
    }
    public static bool SendStringToPrinter(string szPrinterName, string szString)
    {
        IntPtr pBytes;
        Int32 dwCount;
        // How many characters are in the string?
        dwCount = szString.Length;
        // Assume that the printer is expecting ANSI text, and then convert
        // the string to ANSI text.
        pBytes = Marshal.StringToCoTaskMemAnsi(szString);
        // Send the converted ANSI string to the printer.
        SendBytesToPrinter(szPrinterName, pBytes, dwCount);
        Marshal.FreeCoTaskMem(pBytes);
        return true;
    }
}

Step 2.) Create a form with text box and button (text box will hold the ZPL to send in this example). In button click event add code...

private void button1_Click(object sender, EventArgs e)
        {
            // Allow the user to select a printer.
            PrintDialog pd = new PrintDialog();
            pd.PrinterSettings = new PrinterSettings();
            if (DialogResult.OK == pd.ShowDialog(this))
            {
                // Send a printer-specific to the printer.
                RawPrinterHelper.SendStringToPrinter(pd.PrinterSettings.PrinterName, textBox1.Text);
                MessageBox.Show("Data sent to printer.");
            }
            else
            {
                MessageBox.Show("Data not sent to printer.");
            }
        }

With this solution, you can tweak to meet specific requirements. Perhaps hardcode the specific printer. Perhaps derive the ZPL text dynamically rather than from a text box. Whatever. Perhaps you don't need a graphical interface, but this shows how to send the ZPL. Your use depends on your needs.

Encapsulation vs Abstraction?

Abstraction is the concept of describing something in simpler terms, i.e abstracting away the details, in order to focus on what is important (This is also seen in abstract art, for example, where the artist focuses on the building blocks of images, such as colour or shapes). The same idea translates to OOP by using an inheritance hierarchy, where more abstract concepts are at the top and more concrete ideas, at the bottom, build upon their abstractions. At its most abstract level there is no implementation details at all and perhaps very few commonalities, which are added as the abstraction decreases.

As an example, at the top might be an interface with a single method, then the next level, provides several abstract classes, which may or may not fill in some of the details about the top level, but branches by adding their own abstract methods, then for each of these abstract classes are concrete classes providing implementations of all the remaining methods.

Encapsulation is a technique. It may or may not be for aiding in abstraction, but it is certainly about information hiding and/or organisation. It demands data and functions be grouped in some way - of course good OOP practice demands that they should be grouped by abstraction. However, there are other uses which just aid in maintainability etc.

How to kill a thread instantly in C#?

The reason it's hard to just kill a thread is because the language designers want to avoid the following problem: your thread takes a lock, and then you kill it before it can release it. Now anyone who needs that lock will get stuck.

What you have to do is use some global variable to tell the thread to stop. You have to manually, in your thread code, check that global variable and return if you see it indicates you should stop.

How do I change the font-size of an <option> element within <select>?

Like most form controls in HTML, the results of applying CSS to <select> and <option> elements vary a lot between browsers. Chrome, as you've found, won't let you apply and font styles to an <option> element directly --- if you do Inspect Element on it, you'll see the font-size: 14px declaration is crossed through as if it's been overridden by the cascade, but it's actually because Chrome is ignoring it.

However, Chrome will let you apply font styles to the <optgroup> element, so to achieve the result you want you can wrap all the <option>s in an <optgroup> and then apply your font styles to a .styled-select optgroup selector. If you want the optgroup sans-label, you may have to do some clever CSS with positioning or something to hide the white area at the top where the label would be shown, but that should be possible.

Forked to a new JSFiddle to show you what I mean:

http://jsfiddle.net/zRtbZ/

Windows Explorer "Command Prompt Here"


http://www.petefreitag.com/item/146.cfm

  • Open up windows explorer

  • Tools -> Folder Options.

  • File Types Tab

  • Select the Folder file type

  • Click Advanced

  • Click New

  • For the Action type what ever you want the context menu to display, I used Command Prompt.

  • For the Application used to perform the action use c:\windows\system32\cmd.exe (note on win2k you will want to specify the winnt directory instead of the windows directory)

Adding to a vector of pair

IMHO, a very nice solution is to use c++11 emplace_back function:

revenue.emplace_back("string", map[i].second);

It just creates a new element in place.

How do I solve this "Cannot read property 'appendChild' of null" error?

Your condition id !== 0 will always be different that zero because you are assigning a string value. On pages where the element with id views_slideshow_controls_text_next_slideshow-block is not found, you will still try to append the img element, which causes the Cannot read property 'appendChild' of null error.

Instead of assigning a string value, you can assign the DOM element and verify if it exists within the page.

window.onload = function loadContIcons() {
    var elem = document.createElement("img");
    elem.src = "http://arno.agnian.com/sites/all/themes/agnian/images/up.png";
    elem.setAttribute("class", "up_icon");

    var container = document.getElementById("views_slideshow_controls_text_next_slideshow-block");
    if (container !== null) {
        container.appendChild(elem);
    } else console.log("aaaaa");

    var elem1 = document.createElement("img");
    elem1.src = "http://arno.agnian.com/sites/all/themes/agnian/images/down.png";
    elem1.setAttribute("class", "down_icon");

    container = document.getElementById("views_slideshow_controls_text_previous_slideshow-block");
    if (container !== null) {
        container.appendChild(elem1);
    } else console.log("aaaaa");
}

What are file descriptors, explained in simple terms?

Any operating system has processes (p's) running, say p1, p2, p3 and so forth. Each process usually makes an ongoing usage of files.

Each process is consisted of a process tree (or a process table, in another phrasing).

Usually, Operating systems represent each file in each process by a number (that is to say, in each process tree/table).

The first file used in the process is file0, second is file1, third is file2, and so forth.

Any such number is a file descriptor.

File descriptors are usually integers (0, 1, 2 and not 0.5, 1.5, 2.5).

Given we often describe processes as "process-tables", and given that tables has rows (entries) we can say that the file descriptor cell in each entry, uses to represent the whole entry.

In a similar way, when you open a network socket, it has a socket descriptor.

In some operating systems, you can run out of file descriptors, but such case is extremely rare, and the average computer user shouldn't worry from that.

File descriptors might be global (process A starts in say 0, and ends say in 1 ; Process B starts say in 2, and ends say in 3) and so forth, but as far as I know, usually in modern operating systems, file descriptors are not global, and are actually process-specific (process A starts in say 0 and ends say in 5, while process B starts in 0 and ends say in 10).

How to change SmartGit's licensing option after 30 days of commercial use on ubuntu?

just delete the settings.xml and try againn to setup smartgitHg

How to use the PI constant in C++

On some (especially older) platforms (see the comments below) you might need to

#define _USE_MATH_DEFINES

and then include the necessary header file:

#include <math.h>

and the value of pi can be accessed via:

M_PI

In my math.h (2014) it is defined as:

# define M_PI           3.14159265358979323846  /* pi */

but check your math.h for more. An extract from the "old" math.h (in 2009):

/* Define _USE_MATH_DEFINES before including math.h to expose these macro
 * definitions for common math constants.  These are placed under an #ifdef
 * since these commonly-defined names are not part of the C/C++ standards.
 */

However:

  1. on newer platforms (at least on my 64 bit Ubuntu 14.04) I do not need to define the _USE_MATH_DEFINES

  2. On (recent) Linux platforms there are long double values too provided as a GNU Extension:

    # define M_PIl          3.141592653589793238462643383279502884L /* pi */
    

How to randomize Excel rows

Use Excel Online (Google Sheets).. And install Power Tools for Google Sheets.. Then in Google Sheets go to Addons tab and start Power Tools. Then choose Randomize from Power Tools menu. Select Shuffle. Then select choices of your test in excel sheet. Then select Cells in each row and click Shuffle from Power Tools menu. This will shuffle each row's selected cells independently from one another.

get the value of "onclick" with jQuery?

I'm not quite sure how to do this in jQuery... but this works:

var x = document.getElementById('google').attributes;
for (var i in x) {
 if (x[i].name == "onclick") alert(x[i].firstChild.data);
}

but like Harshath said it would be better if you used event listeners, as removing and adding this function back into the onclick event may be troublesome.

What is the difference between an expression and a statement in Python?

An expression is something that can be reduced to a value, for example "1+3" is an expression, but "foo = 1+3" is not.

It's easy to check:

print(foo = 1+3)

If it doesn't work, it's a statement, if it does, it's an expression.

Another statement could be:

class Foo(Bar): pass

as it cannot be reduced to a value.

Programmatically extract contents of InstallShield setup.exe

There's no supported way to do this, but won't you have to examine the files related to each installer to figure out how to actually install them after extracting them? Assuming you can spend the time to figure out which command-line applies, here are some candidate parameters that normally allow you to extract an installation.

MSI Based (may not result in a usable image for an InstallScript MSI installation):

  • setup.exe /a /s /v"/qn TARGETDIR=\"choose-a-location\""

    or, to also extract prerequisites (for versions where it works),

  • setup.exe /a"choose-another-location" /s /v"/qn TARGETDIR=\"choose-a-location\""

InstallScript based:

  • setup.exe /s /extract_all

Suite based (may not be obvious how to install the resulting files):

  • setup.exe /silent /stage_only ISRootStagePath="choose-a-location"

How to find elements with 'value=x'?

Use the following selector.

$('#attached_docs [value=123]').remove();

How can I check the size of a file in a Windows batch script?

Just saw this old question looking to see if Windows had something built in. The ~z thing is something I didn't know about, but not applicable for me. I ended up with a Perl one-liner:

@echo off

set yourfile=output.txt
set maxsize=10000

perl -e "-s $ENV{yourfile} > $ENV{maxsize} ? exit 1 : exit 0"
rem if %errorlevel%. equ 1. goto abort
if errorlevel 1 goto abort

echo OK!
exit /b 0

:abort
echo Bad!
exit /b 1

Padding or margin value in pixels as integer using jQuery

Parse int

parseInt(canvas.css("margin-left")); 

returns 0 for 0px

How to find all duplicate from a List<string>?

In .NET framework 3.5 and above you can use Enumerable.GroupBy which returns an enumerable of enumerables of duplicate keys, and then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable:

var duplicateKeys = list.GroupBy(x => x)
                        .Where(group => group.Count() > 1)
                        .Select(group => group.Key);

Select query to get data from SQL Server

you can use ExecuteScalar() in place of ExecuteNonQuery() to get a single result use it like this

Int32 result= (Int32) command.ExecuteScalar();
Console.WriteLine(String.Format("{0}", result));

It will execute the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.

As you want only one row in return, remove this use of SqlDataReader from your code

using (SqlDataReader reader = command.ExecuteReader())
{
    // iterate your results here
    Console.WriteLine(String.Format("{0}",reader["id"]));
}

because it will again execute your command and effect your page performance.

Resize to fit image in div, and center horizontally and vertically

NOT SUPPORTED BY IE

More info here: Can I Use?

_x000D_
_x000D_
.container {_x000D_
  overflow: hidden;_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
}_x000D_
_x000D_
.container img {_x000D_
  object-fit: cover;_x000D_
  width: 100%;_x000D_
  min-height: 100%;_x000D_
}
_x000D_
<div class='container'>_x000D_
    <img src='http://i.imgur.com/H9lpVkZ.jpg' />_x000D_
</div>
_x000D_
_x000D_
_x000D_

Adding image to JFrame

As martijn-courteaux said, create a custom component it's the better option. In C# exists a component called PictureBox and I tried to create this component for Java, here is the code:

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JComponent;

public class JPictureBox extends JComponent {

    private Icon icon = null;
    private final Dimension dimension = new Dimension(100, 100);
    private Image image = null;
    private ImageIcon ii = null;
    private SizeMode sizeMode = SizeMode.STRETCH;
    private int newHeight, newWidth, originalHeight, originalWidth;

    public JPictureBox() {
        JPictureBox.this.setPreferredSize(dimension);
        JPictureBox.this.setOpaque(false);
        JPictureBox.this.setSizeMode(SizeMode.STRETCH);
    }

    @Override
    public void paintComponent(Graphics g) {
        if (ii != null) {
            switch (getSizeMode()) {
                case NORMAL:
                    g.drawImage(image, 0, 0, ii.getIconWidth(), ii.getIconHeight(), null);
                    break;
                case ZOOM:
                    aspectRatio();
                    g.drawImage(image, 0, 0, newWidth, newHeight, null);
                    break;
                case STRETCH:
                    g.drawImage(image, 0, 0, this.getWidth(), this.getHeight(), null);
                    break;
                case CENTER:
                    g.drawImage(image, (int) (this.getWidth() / 2) - (int) (ii.getIconWidth() / 2), (int) (this.getHeight() / 2) - (int) (ii.getIconHeight() / 2), ii.getIconWidth(), ii.getIconHeight(), null);
                    break;
                default:
                    g.drawImage(image, 0, 0, this.getWidth(), this.getHeight(), null);
            }
        }
    }

    public Icon getIcon() {
        return icon;
    }

    public void setIcon(Icon icon) {
        this.icon = icon;
        ii = (ImageIcon) icon;
        image = ii.getImage();
        originalHeight = ii.getIconHeight();
        originalWidth = ii.getIconWidth();
    }

    public SizeMode getSizeMode() {
        return sizeMode;
    }

    public void setSizeMode(SizeMode sizeMode) {
        this.sizeMode = sizeMode;
    }

    public enum SizeMode {
        NORMAL,
        STRETCH,
        CENTER,
        ZOOM
    }

    private void aspectRatio() {
        if (ii != null) {
            newHeight = this.getHeight();
            newWidth = (originalWidth * newHeight) / originalHeight;
        }
    }

}

If you want to add an image, choose the JPictureBox, after that go to Properties and find "icon" property and select an image. If you want to change the sizeMode property then choose the JPictureBox, after that go to Properties and find "sizeMode" property, you can choose some values:

  • NORMAL value, the image is positioned in the upper-left corner of the JPictureBox.
  • STRETCH value causes the image to stretch or shrink to fit the JPictureBox.
  • ZOOM value causes the image to be stretched or shrunk to fit the JPictureBox; however, the aspect ratio in the original is maintained.
  • CENTER value causes the image to be centered in the client area.

If you want to learn more about this topic, you can check this video.

Also you can see the code on Gitlab or Github.

How to escape comma and double quote at same time for CSV file?

String stringWithQuates = "\""+ "your,comma,separated,string" + "\"";

this will retain the comma in CSV file

jQuery - setting the selected value of a select control via its text description

Easiest way with 1.7+ is:

$("#myDropDown option:text=" + myText +"").attr("selected", "selected"); 

1.9+

$("#myDropDown option:text=" + myText +"").prop("selected", "selected"); 

Tested and works.

How to exit from the application and show the home screen?

Maybe my code can hepls (Main_Activity.java):

    @Override
    protected void onDestroy() {
        super.onDestroy();
        this.finish();
        exit(0);
    }

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event)  {
        switch(keyCode)    {
            case KeyEvent.KEYCODE_BACK:
                AlertDialog.Builder builder = new AlertDialog.Builder(this);
                builder.setTitle("My application").setMessage("Keep playing?").setIcon(R.drawable.icon);
                // Go to backgroung
                builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) { moveTaskToBack(true); }
                });
                // Exit from app calling protected void onDestroy()
                builder.setNegativeButton("CLOSE APPLICATION", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) { onDestroy(); }
                });
                // Close this dialog
                builder.setNeutralButton("CANCEL", new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) { dialog.cancel(); }
                });
                AlertDialog dialog = builder.create();
                dialog.show();
                return true;
        }
        return false;
    }

Regular expression to match standard 10 digit phone number

The expressions for 1, 3 and 4 are quite similar, so you can use:

^([1-9]\d{2})([- .])(\d{3})$2(\d{4})$

Note that, depending on the language and brand of regexes used, you might need to put \2 instead of $2 or such matching might not be supported at all.

I see no good way to combine this with the format 2, apart from the obvious ^(regex for 1,3,4|regex for 2)$ which is ugly, clumsy and makes it hard to get out the parts of the numbers.

As for the area code, you can add (\+\d)? to the beginning to capture a single-digit area code (sorry, I don't know the format of your area codes).

cannot import name patterns

patterns module is not supported.. mine worked with this.

from django.conf.urls import *
from django.contrib import admin
admin.autodiscover()

urlpatterns = [
    url(r'^admin/', include(admin.site.urls)),
    # ... your url patterns
]

How to convert Moment.js date to users local timezone?

Use utcOffset function.

var testDateUtc = moment.utc("2015-01-30 10:00:00");
var localDate = moment(testDateUtc).utcOffset(10 * 60); //set timezone offset in minutes
console.log(localDate.format()); //2015-01-30T20:00:00+10:00

Postman: How to make multiple requests at the same time

If you are only doing GET requests and you need another simple solution from within your Chrome browser, just install the "Open Multiple URLs" extension:

https://chrome.google.com/webstore/detail/open-multiple-urls/oifijhaokejakekmnjmphonojcfkpbbh?hl=en

I've just ran 1500 url's at once, did lag google a bit but it works.

get the margin size of an element with jquery

From jQuery's website

Shorthand CSS properties (e.g. margin, background, border) are not supported. For example, if you want to retrieve the rendered margin, use: $(elem).css('marginTop') and $(elem).css('marginRight'), and so on.

Go to "next" iteration in JavaScript forEach loop

JavaScript's forEach works a bit different from how one might be used to from other languages for each loops. If reading on the MDN, it says that a function is executed for each of the elements in the array, in ascending order. To continue to the next element, that is, run the next function, you can simply return the current function without having it do any computation.

Adding a return and it will go to the next run of the loop:

_x000D_
_x000D_
var myArr = [1,2,3,4];_x000D_
_x000D_
myArr.forEach(function(elem){_x000D_
  if (elem === 3) {_x000D_
    return;_x000D_
  }_x000D_
_x000D_
  console.log(elem);_x000D_
});
_x000D_
_x000D_
_x000D_

Output: 1, 2, 4

Add primary key to existing table

I think something like this should work

-- drop current primary key constraint
ALTER TABLE dbo.persion 
DROP CONSTRAINT PK_persionId;
GO

-- add new auto incremented field
ALTER TABLE dbo.persion 
ADD pmid BIGINT IDENTITY;
GO

-- create new primary key constraint
ALTER TABLE dbo.persion 
ADD CONSTRAINT PK_persionId PRIMARY KEY NONCLUSTERED (pmid, persionId);
GO

The activity must be exported or contain an intent-filter

Sometimes if you change the starting activity you have to click edit in the run dropdown play button and in app change the Launch Options Activity to the one you have set the LAUNCHER intent filter in the manifest.

Check if ADODB connection is open

This is an old topic, but in case anyone else is still looking...

I was having trouble after an undock event. An open db connection saved in a global object would error, even after reconnecting to the network. This was due to the TCP connection being forcibly terminated by remote host. (Error -2147467259: TCP Provider: An existing connection was forcibly closed by the remote host.)

However, the error would only show up after the first transaction was attempted. Up to that point, neither Connection.State nor Connection.Version (per solutions above) would reveal any error.

So I wrote the small sub below to force the error - hope it's useful.

Performance testing on my setup (Access 2016, SQL Svr 2008R2) was approx 0.5ms per call.

Function adoIsConnected(adoCn As ADODB.Connection) As Boolean

    '----------------------------------------------------------------
    '#PURPOSE: Checks whether the supplied db connection is alive and
    '          hasn't had it's TCP connection forcibly closed by remote
    '          host, for example, as happens during an undock event
    '#RETURNS: True if the supplied db is connected and error-free, 
    '          False otherwise
    '#AUTHOR:  Belladonna
    '----------------------------------------------------------------

    Dim i As Long
    Dim cmd As New ADODB.Command

    'Set up SQL command to return 1
    cmd.CommandText = "SELECT 1"
    cmd.ActiveConnection = adoCn

    'Run a simple query, to test the connection
    On Error Resume Next
    i = cmd.Execute.Fields(0)
    On Error GoTo 0

    'Tidy up
    Set cmd = Nothing

    'If i is 1, connection is open
    If i = 1 Then
        adoIsConnected = True
    Else
        adoIsConnected = False
    End If

End Function

Combining (concatenating) date and time into a datetime

DECLARE @ADate Date, @ATime Time, @ADateTime Datetime

SELECT @ADate = '2010-02-20', @ATime = '18:53:00.0000000'

SET @ADateTime = CAST   (
    CONVERT(Varchar(10), @ADate, 112) + ' ' +   
    CONVERT(Varchar(8), @ATime) AS DateTime)

SELECT @ADateTime [A nice datetime :)]

This will render you a valid result.

Remove a modified file from pull request

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

Here's how I recommend you do this:

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

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

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

How to deal with missing src/test/java source folder in Android/Maven project?

This is possibly caused due to lost source directory.

Right click on the folder src -> Change to Source Folder

A non-blocking read on a subprocess.PIPE in Python

I have often had a similar problem; Python programs I write frequently need to have the ability to execute some primary functionality while simultaneously accepting user input from the command line (stdin). Simply putting the user input handling functionality in another thread doesn't solve the problem because readline() blocks and has no timeout. If the primary functionality is complete and there is no longer any need to wait for further user input I typically want my program to exit, but it can't because readline() is still blocking in the other thread waiting for a line. A solution I have found to this problem is to make stdin a non-blocking file using the fcntl module:

import fcntl
import os
import sys

# make stdin a non-blocking file
fd = sys.stdin.fileno()
fl = fcntl.fcntl(fd, fcntl.F_GETFL)
fcntl.fcntl(fd, fcntl.F_SETFL, fl | os.O_NONBLOCK)

# user input handling thread
while mainThreadIsRunning:
      try: input = sys.stdin.readline()
      except: continue
      handleInput(input)

In my opinion this is a bit cleaner than using the select or signal modules to solve this problem but then again it only works on UNIX...

Convert bytes to bits in python

Operations are much faster when you work at the integer level. In particular, converting to a string as suggested here is really slow.

If you want bit 7 and 8 only, use e.g.

val = (byte >> 6) & 3

(this is: shift the byte 6 bits to the right - dropping them. Then keep only the last two bits 3 is the number with the first two bits set...)

These can easily be translated into simple CPU operations that are super fast.

When to use .First and when to use .FirstOrDefault with LINQ?

.First will throw an exception when there are no results. .FirstOrDefault won't, it will simply return either null (reference types) or the default value of the value type. (e.g like 0 for an int.) The question here is not when you want the default type, but more: Are you willing to handle an exception or handle a default value? Since exceptions should be exceptional, FirstOrDefault is preferred when you're not sure if you're going to get results out of your query. When logically the data should be there, exception handling can be considered.

Skip() and Take() are normally used when setting up paging in results. (Like showing the first 10 results, and the next 10 on the next page, etc.)

Hope this helps.

make: Nothing to be done for `all'

Sometimes "Nothing to be done for all" error can be caused by spaces before command in makefile rule instead of tab. Please ensure that you use tabs instead of spaces inside of your rules.

all:
<\t>$(CC) $(CFLAGS) ...

instead of

all:
    $(CC) $(CFLAGS) ...

Please see the GNU make manual for the rule syntax description: https://www.gnu.org/software/make/manual/make.html#Rule-Syntax

AlertDialog styling - how to change style (color) of title, message, etc

It depends how much you want to customize the alert dialog. I have different steps in order to customize the alert dialog. Please visit: https://stackoverflow.com/a/33439849/5475941

enter image description here enter image description here enter image description here enter image description here

MySQL trigger if condition exists

I think you mean to update it back to the OLD password, when the NEW one is not supplied.

DROP TRIGGER IF EXISTS upd_user;

DELIMITER $$

    CREATE TRIGGER upd_user BEFORE UPDATE ON `user`
    FOR EACH ROW BEGIN
      IF (NEW.password IS NULL OR NEW.password = '') THEN
            SET NEW.password = OLD.password;
      ELSE
            SET NEW.password = Password(NEW.Password);
      END IF;
    END$$

DELIMITER ;

However, this means a user can never blank out a password.


If the password field (already encrypted) is being sent back in the update to mySQL, then it will not be null or blank, and MySQL will attempt to redo the Password() function on it. To detect this, use this code instead

DELIMITER $$

    CREATE TRIGGER upd_user BEFORE UPDATE ON `user`
    FOR EACH ROW BEGIN
      IF (NEW.password IS NULL OR NEW.password = '' OR NEW.password = OLD.password) THEN
            SET NEW.password = OLD.password;
      ELSE
            SET NEW.password = Password(NEW.Password);
      END IF;
    END$$

DELIMITER ;

jQuery ajax call to REST service

I think there is no need to specify

'http://localhost:8080`" 

in the URI part.. because. if you specify it, You'll have to change it manually for every environment.

Only

"/restws/json/product/get" also works

Easier way to create circle div than using an image?

basically this uses div's position absolute to place a character at the given coordinates. so using the parametric equation for a circle, you can draw a circle. if you were to change div's position to relative, it'll result in a sine wave...

in essence we are graphing equations by abusing the position property. i'm not versed well in css, so someone can surely make this more elegant. enjoy.

this works on all browsers and mobile devices (that i'm aware of). i use it on my own website to draw sine waves of text (www.cpixel.com). the original source of this code is found here: www.mathopenref.com/coordcirclealgorithm.html

    <html>
    <head></head>
    <body>
    <script language="Javascript">

    var x_center = 50; //0 in both x_center and y_center will place the center
    var y_center = 50; // at the top left of the browser
    var resolution_step = 360; //how many times to stop along the circle to plot your character.
    var radius = 50; //how big ya want your circle?
    var plot_character = "·"; //could use any character here, try letters/words for cool effects
    var div_top_offset=10;
    var div_left_offset=10;
    var x,y;

    for ( var angle_theta = 0;  angle_theta < 2 * Math.PI;  angle_theta += 2 * Math.PI/resolution_step ){
        x = x_center + radius * Math.cos(angle_theta);
        y = y_center - radius * Math.sin(angle_theta);
        document.write("<div style='position:absolute;top:" + (y+div_top_offset) + ";left:"+ (x+div_left_offset) + "'>" + plot_character + "</div>");
    }

    </script>
    </body>
    </html>

One-line list comprehension: if-else variants

I was able to do this

>>> [x if x % 2 != 0 else x * 100 for x in range(1,10)]
    [1, 200, 3, 400, 5, 600, 7, 800, 9]
>>>

What happened to the .pull-left and .pull-right classes in Bootstrap 4?

Changed to float-right float-left float-xx-left and float-xx-right

How to set auto increment primary key in PostgreSQL?

Try this command:

ALTER TABLE your_table ADD COLUMN key_column BIGSERIAL PRIMARY KEY;

Try it with the same DB-user as the one you have created the table.

How to vertically center a container in Bootstrap?

Update 2020

Bootstrap 4 includes flexbox, so the method of vertical centering is much easier and doesn't require extra CSS.

Just use the d-flex and align-items-center utility classes..

<div class="jumbotron d-flex align-items-center">
  <div class="container">
    content
  </div>
</div>

http://www.codeply.com/go/ui6ABmMTLv

Important: Vertical centering is relative to height. The parent container of the items you're attempting to center must have a defined height. If you want the height of the page use vh-100 or min-vh-100 on the parent! For example:

<div class="jumbotron d-flex align-items-center min-vh-100">
  <div class="container text-center">
    I am centered vertically
  </div>
</div>

Also see: https://stackoverflow.com/questions/42252443/vertical-align-center-in-bootstrap-4

Logo image and H1 heading on the same line

I'd use bootstrap and set the html as:

<div class="row">
    <div class="col-md-4">
        <img src="img/logo.png" alt="logo" />
    </div>
    <div class="col-md-8">
        <h1>My website name</h1>
    </div>
</div>

How to re-sign the ipa file?

Kind of old question, but with the latest XCode, codesign is easy:

$ codesign -s my_certificate example.ipa 

$ codesign -vv example.ipa
example.ipa: valid on disk
example.ipa: satisfies its Designated Requirement

maven... Failed to clean project: Failed to delete ..\org.ow2.util.asm-asm-tree-3.1.jar

For linux users: possible solution.

Build error due to "Failed to delete < any-file-or-folder >" will occur if there is by chance of only delete access provided to root user rather to normal-user.

Fix : type ll command to list file that cannot be deleted, if the file is given root access, change to normal user by :

sudo chown -R user-name:user-name filename

Later try for maven clean and build.

Which is a better way to check if an array has more than one element?

Obviously using count($arr) > 1 (sizeof is just an alias for count) is the best solution. Depending on the structure of your array, there might be tons of elements but no $array['1'] element.

Label python data points on plot

How about print (x, y) at once.

from matplotlib import pyplot as plt

fig = plt.figure()
ax = fig.add_subplot(111)

A = -0.75, -0.25, 0, 0.25, 0.5, 0.75, 1.0
B = 0.73, 0.97, 1.0, 0.97, 0.88, 0.73, 0.54

plt.plot(A,B)
for xy in zip(A, B):                                       # <--
    ax.annotate('(%s, %s)' % xy, xy=xy, textcoords='data') # <--

plt.grid()
plt.show()

enter image description here

Creating a copy of an object in C#

The easiest way to do this is writing a copy constructor in the MyClass class.

Something like this:

namespace Example
{
    class MyClass
    {
        public int val;

        public MyClass()
        {
        }

        public MyClass(MyClass other)
        {
            val = other.val;
        }
    }
}

The second constructor simply accepts a parameter of his own type (the one you want to copy) and creates a new object assigned with the same value

class Program
{
    static void Main(string[] args)
    {
        MyClass objectA = new MyClass();
        MyClass objectB = new MyClass(objectA);
        objectA.val = 10;
        objectB.val = 20;
        Console.WriteLine("objectA.val = {0}", objectA.val);
        Console.WriteLine("objectB.val = {0}", objectB.val);
        Console.ReadKey();
    }
}

output:

objectA.val = 10

objectB.val = 20               

vertical-align: middle with Bootstrap 2

i use this

<style>
html, body{height:100%;margin:0;padding:0 0} 
.container-fluid{height:100%;display:table;width:100%;padding-right:0;padding-left: 0}   
.row-fluid{height:100%;display:table-cell;vertical-align:middle;width:100%}
.centering{float:none;margin:0 auto} 
</style>
<body>
<div class="container-fluid">
     <div class="row-fluid">
     <div class="offset3 span6 centering">
            content here
         </div>
    </div>
 </div>
</body>

whitespaces in the path of windows filepath

There is no problem with whitespaces in the path since you're not using the "shell" to open the file. Here is a session from the windows console to prove the point. You're doing something else wrong

Python 2.7.2 (default, Jun 12 2011, 14:24:46) [MSC v.1500 64 bit (AMD64)] on wi
32
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>>
>>> os.makedirs("C:/ABC/SEM 2/testfiles")
>>> open("C:/ABC/SEM 2/testfiles/all.txt","w")
<open file 'C:/ABC/SEM 2/testfiles/all.txt', mode 'w' at 0x0000000001D95420>
>>> exit()

C:\Users\Gnibbler>dir "C:\ABC\SEM 2\testfiles"
 Volume in drive C has no label.
 Volume Serial Number is 46A0-BB64

 Directory of c:\ABC\SEM 2\testfiles

13/02/2013  10:20 PM    <DIR>          .
13/02/2013  10:20 PM    <DIR>          ..
13/02/2013  10:20 PM                 0 all.txt
               1 File(s)              0 bytes
               2 Dir(s)  78,929,309,696 bytes free

C:\Users\Gnibbler>