Programs & Examples On #Console.writeline

Writes the specified data, followed by the current line terminator, to the standard output stream.

How can I write these variables into one line of code in C#?

You can do your whole program in one line! Yes, that is right, one line!

Console.WriteLine(DateTime.Now.ToString("yyyy.MM.dd"));

You may notice that I did not use the same date format as you. That is because you should use the International Date Format as described in this W3C document. Every time you don't use it, somewhere a cute little animal dies.

Where does Console.WriteLine go in ASP.NET?

if you happened to use NLog in your ASP.net project, you can add a Debugger target:

<targets>
    <target name="debugger" xsi:type="Debugger"
            layout="${date:format=HH\:mm\:ss}|${pad:padding=5:inner=${level:uppercase=true}}|${message} "/>

and writes logs to this target for the levels you want:

<rules>
    <logger name="*" minlevel="Trace" writeTo="debugger" />

now you have console output just like Jetty in "Output" window of VS, and make sure you are running in Debug Mode(F5).

$(document).on('click', '#id', function() {}) vs $('#id').on('click', function(){})

Consider following code

<ul id="myTask">
  <li>Coding</li>
  <li>Answering</li>
  <li>Getting Paid</li>
</ul>

Now, here goes the difference

// Remove the myTask item when clicked.
$('#myTask').children().click(function () {
  $(this).remove()
});

Now, what if we add a myTask again?

$('#myTask').append('<li>Answer this question on SO</li>');

Clicking this myTask item will not remove it from the list, since it doesn't have any event handlers bound. If instead we'd used .on, the new item would work without any extra effort on our part. Here's how the .on version would look:

$('#myTask').on('click', 'li', function (event) {
  $(event.target).remove()
});

Summary:

The difference between .on() and .click() would be that .click() may not work when the DOM elements associated with the .click() event are added dynamically at a later point while .on() can be used in situations where the DOM elements associated with the .on() call may be generated dynamically at a later point.

How to check if a date is in a given range?

Convert them into dates or timestamp integers and then just check of $date_from_user is <= $end_date and >= $start_date

If statement for strings in python?

If should be if. Your program should look like this:

answer = raw_input("Is the information correct? Enter Y for yes or N for no")
if answer.upper() == 'Y':
    print("this will do the calculation")
else:
    exit()

Note also that the indentation is important, because it marks a block in Python.

Difference between binary semaphore and mutex

Mutex is used to protect the sensitive code and data, semaphore is used to synchronization.You also can have practical use with protect the sensitive code, but there might be a risk that release the protection by the other thread by operation V.So The main difference between bi-semaphore and mutex is the ownership.For instance by toilet , Mutex is like that one can enter the toilet and lock the door, no one else can enter until the man get out, bi-semaphore is like that one can enter the toilet and lock the door, but someone else could enter by asking the administrator to open the door, it's ridiculous.

How to convert "0" and "1" to false and true

(returnValue != "1" ? false : true);

Create a function with optional call variables

Powershell provides a lot of built-in support for common parameter scenarios, including mandatory parameters, optional parameters, "switch" (aka flag) parameters, and "parameter sets."

By default, all parameters are optional. The most basic approach is to simply check each one for $null, then implement whatever logic you want from there. This is basically what you have already shown in your sample code.

If you want to learn about all of the special support that Powershell can give you, check out these links:

about_Functions

about_Functions_Advanced

about_Functions_Advanced_Parameters

How do I access named capturing groups in a .NET Regex?

The following code sample, will match the pattern even in case of space characters in between. i.e. :

<td><a href='/path/to/file'>Name of File</a></td>

as well as:

<td> <a      href='/path/to/file' >Name of File</a>  </td>

Method returns true or false, depending on whether the input htmlTd string matches the pattern or no. If it matches, the out params contain the link and name respectively.

/// <summary>
/// Assigns proper values to link and name, if the htmlId matches the pattern
/// </summary>
/// <returns>true if success, false otherwise</returns>
public static bool TryGetHrefDetails(string htmlTd, out string link, out string name)
{
    link = null;
    name = null;

    string pattern = "<td>\\s*<a\\s*href\\s*=\\s*(?:\"(?<link>[^\"]*)\"|(?<link>\\S+))\\s*>(?<name>.*)\\s*</a>\\s*</td>";

    if (Regex.IsMatch(htmlTd, pattern))
    {
        Regex r = new Regex(pattern,  RegexOptions.IgnoreCase | RegexOptions.Compiled);
        link = r.Match(htmlTd).Result("${link}");
        name = r.Match(htmlTd).Result("${name}");
        return true;
    }
    else
        return false;
}

I have tested this and it works correctly.

How do I do top 1 in Oracle?

Use:

SELECT x.*
  FROM (SELECT fname 
          FROM MyTbl) x
 WHERE ROWNUM = 1

If using Oracle9i+, you could look at using analytic functions like ROW_NUMBER() but they won't perform as well as ROWNUM.

Epoch vs Iteration when training neural networks

To understand the difference between these you must understand the Gradient Descent Algorithm and its Variants.

Before I start with the actual answer, I would like to build some background.

A batch is the complete dataset. Its size is the total number of training examples in the available dataset.

Mini-batch size is the number of examples the learning algorithm processes in a single pass (forward and backward).

A Mini-batch is a small part of the dataset of given mini-batch size.

Iterations is the number of batches of data the algorithm has seen (or simply the number of passes the algorithm has done on the dataset).

Epochs is the number of times a learning algorithm sees the complete dataset. Now, this may not be equal to the number of iterations, as the dataset can also be processed in mini-batches, in essence, a single pass may process only a part of the dataset. In such cases, the number of iterations is not equal to the number of epochs.

In the case of Batch gradient descent, the whole batch is processed on each training pass. Therefore, the gradient descent optimizer results in smoother convergence than Mini-batch gradient descent, but it takes more time. The batch gradient descent is guaranteed to find an optimum if it exists.

Stochastic gradient descent is a special case of mini-batch gradient descent in which the mini-batch size is 1.

Batch gradient descent vs Mini-batch gradient descent

Comparison of batch, stochastic and mini-batch gradient descents.

git index.lock File exists when I try to commit, but cannot delete the file

On Linux, Unix, Git Bash, or Cygwin, try:

rm -f .git/index.lock

On Windows Command Prompt, try:

del .git\index.lock


For Windows:

  • From a PowerShell console opened as administrator, try

    rm -Force ./.git/index.lock
    
  • If that does not work, you must kill all git.exe processes

    taskkill /F /IM git.exe
    

    SUCCESS: The process "git.exe" with PID 20448 has been terminated.
    SUCCESS: The process "git.exe" with PID 11312 has been terminated.
    SUCCESS: The process "git.exe" with PID 23868 has been terminated.
    SUCCESS: The process "git.exe" with PID 27496 has been terminated.
    SUCCESS: The process "git.exe" with PID 33480 has been terminated.
    SUCCESS: The process "git.exe" with PID 28036 has been terminated. \

    rm -Force ./.git/index.lock
    

What's the best way to store a group of constants that my program uses?

Yes, a static class for storing constants would be just fine, except for constants that are related to specific types.

How can I include null values in a MIN or MAX?

Use the analytic function :

select case when 
    max(field) keep (dense_rank first order by datfin desc nulls first) is null then 1 
    else 0 end as flag 
from MYTABLE;

SVN: Is there a way to mark a file as "do not commit"?

You can configure the "ignore-on-commit" changelist directly with TortoiseSVN. No need to configure any other changelist including all the others files

1) Click "SVN Commit..." (we will not commit, just a way to find a graphical menu for the changelist) 2) On the list Right click on the file you want to exclude. 3) Menu: move to changelist > ignore-on-commit

The next time you do a SVN Commit... The files will appear unchecked at the end of the list, under the category ignore-on-commit.

Tested with : TortoiseSVN 1.8.7, Build 25475 - 64 Bit , 2014/05/05 20:52:12, Subversion 1.8.9, -release

Using different Web.config in development and production environment

I'd like to know, too. This helps isolate the problem for me

<connectionStrings configSource="connectionStrings.config"/>

I then keep a connectionStrings.config as well as a "{host} connectionStrings.config". It's still a problem, but if you do this for sections that differ in the two environments, you can deploy and version the same web.config.

(And I don't use VS, btw.)

How to capture Curl output to a file?

For a single file you can use -O instead of -o filename to use the last segment of the URL path as the filename. Example:

curl http://example.com/folder/big-file.iso -O

will save the results to a new file named big-file.iso in the current folder. In this way it works similar to wget but allows you to specify other curl options that are not available when using wget.

Running interactive commands in Paramiko

I'm not familiar with paramiko, but this may work:

ssh_stdin.write('input value')
ssh_stdin.flush()

For information on stdin:

http://docs.python.org/library/sys.html?highlight=stdin#sys.stdin

How do I check if a variable is of a certain type (compare two types) in C?

As another answer mentioned, you can now do this in C11 with _Generic.

For example, here's a macro that will check if some input is compatible with another type:

#include <stdbool.h>
#define isCompatible(x, type) _Generic(x, type: true, default: false)

You can use the macro like so:

double doubleVar;
if (isCompatible(doubleVar, double)) {
    printf("doubleVar is of type double!\n");  // prints
}

int intVar;
if (isCompatible(intVar, double)) {
    printf("intVar is compatible with double too!\n");  // doesn't print
}

This can also be used on other types, including structs. E.g.

struct A {
    int x;
    int y;
};

struct B {
    double a;
    double b;
};

int main(void)
{    
    struct A AVar = {4, 2};
    struct B BVar = {4.2, 5.6};

    if (isCompatible(AVar, struct A)) {
        printf("Works on user-defined types!\n");  // prints
    }

    if (isCompatible(BVar, struct A)) {
        printf("And can differentiate between them too!\n");  // doesn't print
    }

    return 0;
}

And on typedefs.

typedef char* string;

string greeting = "Hello world!";
if (isCompatible(greeting, string)) {
    printf("Can check typedefs.\n");
}

However, it doesn't always give you the answer you expect. For instance, it can't distinguish between an array and a pointer.

int intArray[] = {4, -9, 42, 3};

if (isCompatible(intArray, int*)) {
    printf("Treats arrays like pointers.\n");
}

// The code below doesn't print, even though you'd think it would
if (isCompatible(intArray, int[4])) {
    printf("But at least this works.\n");
}

Answer borrowed from here: http://www.robertgamble.net/2012/01/c11-generic-selections.html

Resizable table columns with jQuery

I tried to add to @user686605's work:

1) changed the cursor to col-resize at the th border

2) fixed the highlight text issue when resizing

I partially succeeded at both. Maybe someone who is better at CSS can help move this forward?

http://jsfiddle.net/telefonica/L2f7F/4/

HTML

<!--Click on th and drag...-->
<table>
    <thead>
        <tr>
            <th><div class="noCrsr">th 1</div></th>
            <th><div class="noCrsr">th 2</div></th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>td 1</td>
            <td>td 2</td>
        </tr>
    </tbody>
</table>

JS

$(function() {
    var pressed = false;
    var start = undefined;
    var startX, startWidth;

    $("table th").mousedown(function(e) {
        start = $(this);
        pressed = true;
        startX = e.pageX;
        startWidth = $(this).width();
        $(start).addClass("resizing");
        $(start).addClass("noSelect");
    });

    $(document).mousemove(function(e) {
        if(pressed) {
            $(start).width(startWidth+(e.pageX-startX));
        }
    });

    $(document).mouseup(function() {
        if(pressed) {
            $(start).removeClass("resizing");
            $(start).removeClass("noSelect");
            pressed = false;
        }
    });
});

CSS

table {
    border-width: 1px;
    border-style: solid;
    border-color: black;
    border-collapse: collapse;
}

table td {
    border-width: 1px;
    border-style: solid;
    border-color: black;
}

table th {
    border: 1px;
    border-style: solid;
    border-color: black;
    background-color: green;
    cursor: col-resize;
}

table th.resizing {
    cursor: col-resize;
}

.noCrsr {
    cursor: default;
    margin-right: +5px;
}

.noSelect {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
}

awk partly string match (if column/word partly matches)

Print lines where the third field is either snow or snowman only:

awk '$3~/^snow(man)?$/' file

Center button under form in bootstrap

With Bootstrap you can simply use class text-center:

<div class="container">
    <div class="row">
        <form>
            <input class="input-xxlarge" type="text" placeholder="Email..">
        </form>

        <div class="text-center">
            <button type="submit" class="btn">Confirm</button>
        </div>
    </div>
</div>

DEMO

How to remove all click event handlers using jQuery?

If you used...

$(function(){
    function myFunc() {
        // ... do something ...
    };
    $('#saveBtn').click(myFunc);
});

... then it will be easier to unbind later.

What is the difference between DBMS and RDBMS?

DBMS : Data Base Management System ..... for storage of data and efficient retrieval of data. Eg: Foxpro

1)A DBMS has to be persistent (it should be accessible when the program created the data donot exist or even the application that created the data restarted).

2) DBMS has to provide some uniform methods independent of a specific application for accessing the information that is stored.

3)DBMS does not impose any constraints or security with regard to data manipulation. It is user or the programmer responsibility to ensure the ACID PROPERTY of the database

4)In DBMS Normalization process will not be present

5)In dbms no relationship concept

6)It supports Single User only

7)It treats Data as Files internally

8)It supports 3 rules of E.F.CODD out off 12 rules

9)It requires low Software and Hardware Requirements.

FoxPro, IMS are Examples

RDBMS: Relational Data Base Management System

.....the database which is used by relations(tables) to acquire information retrieval Eg: oracle, SQL..,

1)RDBMS is based on relational model, in which data is represented in the form of relations, with enforced relationships between the tables.

2)RDBMS defines the integrity constraint for the purpose of holding ACID PROPERTY.

3)In RDBMS, normalization process will be present to check the database table cosistency

4)RDBMS helps in recovery of the database in case of loss of data

5)It is used to establish the relationship concept between two database objects, i.e, tables

6)It supports multiple users

7)It treats data as Tables internally

8)It supports minimum 6 rules of E.F.CODD

9)It requires High software and hardware

Get input value from TextField in iOS alert in Swift

Updated for Swift 3 and above:

//1. Create the alert controller.
let alert = UIAlertController(title: "Some Title", message: "Enter a text", preferredStyle: .alert)

//2. Add the text field. You can configure it however you need.
alert.addTextField { (textField) in
    textField.text = "Some default text"
}

// 3. Grab the value from the text field, and print it when the user clicks OK.
alert.addAction(UIAlertAction(title: "OK", style: .default, handler: { [weak alert] (_) in
    let textField = alert.textFields![0] // Force unwrapping because we know it exists.
    print("Text field: \(textField.text)")
}))

// 4. Present the alert.
self.present(alert, animated: true, completion: nil)

Swift 2.x

Assuming you want an action alert on iOS:

//1. Create the alert controller.            
var alert = UIAlertController(title: "Some Title", message: "Enter a text", preferredStyle: .Alert)

//2. Add the text field. You can configure it however you need.
alert.addTextFieldWithConfigurationHandler({ (textField) -> Void in
    textField.text = "Some default text."
})

//3. Grab the value from the text field, and print it when the user clicks OK. 
alert.addAction(UIAlertAction(title: "OK", style: .Default, handler: { [weak alert] (action) -> Void in
    let textField = alert.textFields![0] as UITextField
    println("Text field: \(textField.text)")
}))

// 4. Present the alert.
self.presentViewController(alert, animated: true, completion: nil)

calling parent class method from child class object in java

Use the keyword super within the overridden method in the child class to use the parent class method. You can only use the keyword within the overridden method though. The example below will help.

public class Parent {
    public int add(int m, int n){
        return m+n;
    }
}


public class Child extends Parent{
    public int add(int m,int n,int o){
        return super.add(super.add(m, n),0);
    }

}


public class SimpleInheritanceTest {
    public static void main(String[] a){
        Child child = new Child();
        child.add(10, 11);
    }
}

The add method in the Child class calls super.add to reuse the addition logic.

How to list active / open connections in Oracle?

select 
    count(1) "NO. Of DB Users", 
    to_char(sysdate,'DD-MON-YYYY:HH24:MI:SS') sys_time
from 
    v$session 
where 
    username is NOT  NULL;

Setting button text via javascript

The value of a button element isn't the displayed text, contrary to what happens to input elements of type button.

You can do this :

 b.appendChild(document.createTextNode('test value'));

Demonstration

Connecting PostgreSQL 9.2.1 with Hibernate

This is a hibernate.cfg.xml for posgresql and it will help you with basic hibernate configurations for posgresql.

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>
        <property name="hibernate.dialect">org.hibernate.dialect.PostgreSQLDialect</property>
        <property name="hibernate.connection.driver_class">org.postgresql.Driver</property>
        <property name="hibernate.connection.username">postgres</property>
        <property name="hibernate.connection.password">password</property>
        <property name="hibernate.connection.url">jdbc:postgresql://localhost:5432/hibernatedb</property>



        <property name="connection_pool_size">1</property>

        <property name="hbm2ddl.auto">create</property>

        <property name="show_sql">true</property>



       <mapping class="org.javabrains.sanjaya.dto.UserDetails"/>

    </session-factory>
</hibernate-configuration>

Maven dependencies are failing with a 501 error

I have the same issue, but I use GitLab instead of Jenkins. The steps I had to do to get over the issue:

  1. My project is in GitLab so it uses the .yml file which points to a Docker image I have to do continuous integration, and the image it uses has the http://maven URLs. So I changed that to https://maven.
  2. That same Dockerfile image had an older version of Maven 3.0.1 that gave me issues just overnight. I updated the Dockerfile to get the latest version 3.6.3
  3. I then deployed that image to my online repository, and updated my Maven project ymlfile to use that new image.
  4. And lastly, I updated my main projects POM file to reference https://maven... instead of http://maven

I realize that is more specific to my setup. But without doing all of the steps above I would still continue to get this error message Return code is: 501 , ReasonPhrase:HTTPS Required

Rearrange columns using cut

using just the shell,

while read -r col1 col2
do
  echo $col2 $col1
done <"file"

curl: (35) SSL connect error

curl 7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.19.1 Basic ECC zlib/1.2.3 libidn/1.18 libssh2/1.4.2

You are using a very old version of curl. My guess is that you run into the bug described 6 years ago. Fix is to update your curl.

How to open a web server port on EC2 instance

Follow the steps that are described on this answer just instead of using the drop down, type the port (8787) in "port range" an then "Add rule".

Go to the "Network & Security" -> Security Group settings in the left hand navigation

enter image description here Find the Security Group that your instance is apart of Click on Inbound Rules enter image description here Use the drop down and add HTTP (port 80) enter image description here Click Apply and enjoy

C++ initial value of reference to non-const must be an lvalue

The &nKByte creates a temporary value, which cannot be bound to a reference to non-const.

You could change void test(float *&x) to void test(float * const &x) or you could just drop the pointer altogether and use void test(float &x); /*...*/ test(nKByte);.

Convert integer to binary in C#

Convert from any classic base to any base in C#

String number = "100";
int fromBase = 16;
int toBase = 10;

String result = Convert.ToString(Convert.ToInt32(number, fromBase), toBase);

// result == "256"

Supported bases are 2, 8, 10 and 16

Including external jar-files in a new jar-file build with Ant

You can use a bit of functionality that is already built in to the ant jar task.

If you go to The documentation for the ant jar task and scroll down to the "merging archives" section there's a snippet for including the all the *.class files from all the jars in you "lib/main" directory:

<jar destfile="build/main/checksites.jar">
    <fileset dir="build/main/classes"/>
    <restrict>
        <name name="**/*.class"/>
        <archives>
            <zips>
                <fileset dir="lib/main" includes="**/*.jar"/>
            </zips>
        </archives>
    </restrict>
    <manifest>
      <attribute name="Main-Class" value="com.acme.checksites.Main"/>
    </manifest>
</jar>

This Creates an executable jar file with a main class "com.acme.checksites.Main", and embeds all the classes from all the jars in lib/main.

It won't do anything clever in case of namespace conflicts, duplicates and things like that. Also, it will include all class files, also the ones that you don't use, so the combined jar file will be full size.

If you need more advanced things like that, take a look at like one-jar and jar jar links

How to set the part of the text view is clickable

more generic answer in kotlin

   fun setClickableText(view: TextView, firstSpan: String, secondSpan: String) {
    val context = view.context
    val builder = SpannableStringBuilder()
    val unClickableSpan = SpannableString(firstSpan)
    val span = SpannableString(" "+secondSpan)

    builder.append(unClickableSpan);
    val clickableSpan: ClickableSpan = object : ClickableSpan() {
        override fun onClick(textView: View) {
            val intent = Intent(context, HomeActivity::class.java)
         context.startActivity(intent)
        }

        override fun updateDrawState(ds: TextPaint) {
            super.updateDrawState(ds)
            ds.isUnderlineText = true
            ds.setTypeface(Typeface.create(Typeface.DEFAULT, Typeface.ITALIC));
        }
    }
    builder.append(span);
    builder.setSpan(clickableSpan, firstSpan.length, firstSpan.length+secondSpan.length+1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE)

    view.setText(builder,TextView.BufferType.SPANNABLE)
    view.setMovementMethod(LinkMovementMethod.getInstance());


}

How to remove leading zeros from alphanumeric text?

Without using Regex or substring() function on String which will be inefficient -

public static String removeZero(String str){
        StringBuffer sb = new StringBuffer(str);
        while (sb.length()>1 && sb.charAt(0) == '0')
            sb.deleteCharAt(0);
        return sb.toString();  // return in String
    }

Can I grep only the first n lines of a file?

The output of head -10 file can be piped to grep in order to accomplish this:

head -10 file | grep …

Using Perl:

perl -ne 'last if $. > 10; print if /pattern/' file

X-Frame-Options on apache

This worked for me on all browsers:

  1. Created one page with all my javascript
  2. Created a 2nd page on the same server and embedded the first page using the object tag.
  3. On my third party site I used the Object tag to embed the 2nd page.
  4. Created a .htaccess file on the original server in the public_html folder and put Header unset X-Frame-Options in it.

javax.net.ssl.SSLHandshakeException: Remote host closed connection during handshake during web service communicaiton

Not an answer yet, but too much for a comment. This is clearly not a server cert problem; the symptoms of that are quite different. From your system's POV, the server appears to be closing during the handshake. There are two possibilities:

The server really is closing, which is a SSL/TLS protocol violation though a fairly minor one; there are quite a few reasons a server might fail to handshake with you but it should send a fatal alert first, which your JSSE or the weblogic equivalent should indicate. In this case there may well be some useful information in the server log, if you are able (and permitted) to communicate with knowledgeable server admin(s). Or you can try putting a network monitor on your client machine, or one close enough it sees all your traffic; personally I like www.wireshark.org. But this usually shows only that the close came immediately after the ClientHello, which doesn't narrow it down much. You don't say if you are supposed to and have configured a "client cert" (actually key&cert, in the form of a Java privateKeyEntry) for this server; if that is required by the server and not correct, some servers may perceive that as an attack and knowingly violate protocol by closing even though officially they should send an alert.

Or, some middlebox in the network, most often a firewall or purportedly-transparent proxy, is deciding it doesn't like your connection and forcing a close. The Proxy you use is an obvious suspect; when you say the "same code" works to other hosts, confirm if you mean through the same proxy (not just a proxy) and using HTTPS (not clear HTTP). If that isn't so, try testing to other hosts with HTTPS through the proxy (you needn't send a full SOAP request, just a GET / if enough). If you can, try connecting without the proxy, or possibly a different proxy, and connecting HTTP (not S) through the proxy to the host (if both support clear) and see if those work.

If you don't mind publishing the actual host (but definitely not any authentication credentials) others can try it. Or you can go to www.ssllabs.com and request they test the server (without publishing the results); this will try several common variations on SSL/TLS connection and report any errors it sees, as well as any security weaknesses.

async await return Task

This is a Task that is returning a Task of type String (C# anonymous function or in other word a delegation is used 'Func')

    public static async Task<string> MyTask()
    {
        //C# anonymous AsyncTask
        return await Task.FromResult<string>(((Func<string>)(() =>
        {
            // your code here
            return  "string result here";

        }))());
    }

Node.js + Nginx - What now?

I proxy independent Node Express applications through Nginx.

Thus new applications can be easily mounted and I can also run other stuff on the same server at different locations.

Here are more details on my setup with Nginx configuration example:

Deploy multiple Node applications on one web server in subfolders with Nginx

Things get tricky with Node when you need to move your application from from localhost to the internet.

There is no common approach for Node deployment.

Google can find tons of articles on this topic, but I was struggling to find the proper solution for the setup I need.

Basically, I have a web server and I want Node applications to be mounted to subfolders (i.e. http://myhost/demo/pet-project/) without introducing any configuration dependency to the application code.

At the same time I want other stuff like blog to run on the same web server.

Sounds simple huh? Apparently not.

In many examples on the web Node applications either run on port 80 or proxied by Nginx to the root.

Even though both approaches are valid for certain use cases, they do not meet my simple yet a little bit exotic criteria.

That is why I created my own Nginx configuration and here is an extract:

upstream pet_project {
  server localhost:3000;
}

server {
  listen 80;
  listen [::]:80;
  server_name frontend;

  location /demo/pet-project {
    alias /opt/demo/pet-project/public/;
    try_files $uri $uri/ @pet-project;
  }

  location @pet-project {
    rewrite /demo/pet-project(.*) $1 break;

    proxy_set_header X-Real-IP $remote_addr;
    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
    proxy_set_header Host $proxy_host;
    proxy_set_header X-NginX-Proxy true;

    proxy_pass http://pet_project;
    proxy_redirect http://pet_project/ /demo/pet-project/;
  }
}

From this example you can notice that I mount my Pet Project Node application running on port 3000 to http://myhost/demo/pet-project.

First Nginx checks if whether the requested resource is a static file available at /opt/demo/pet-project/public/ and if so it serves it as is that is highly efficient, so we do not need to have a redundant layer like Connect static middleware.

Then all other requests are overwritten and proxied to Pet Project Node application, so the Node application does not need to know where it is actually mounted and thus can be moved anywhere purely by configuration.

proxy_redirect is a must to handle Location header properly. This is extremely important if you use res.redirect() in your Node application.

You can easily replicate this setup for multiple Node applications running on different ports and add more location handlers for other purposes.

From: http://skovalyov.blogspot.dk/2012/07/deploy-multiple-node-applications-on.html

Add to integers in a list

Yes, it is possible since lists are mutable.

Look at the built-in enumerate() function to get an idea how to iterate over the list and find each entry's index (which you can then use to assign to the specific list item).

Editing an item in a list<T>

class1 item = lst[index];
item.foo = bar;

Converting Varchar Value to Integer/Decimal Value in SQL Server

The reason could be that the summation exceeded the required number of digits - 4. If you increase the size of the decimal to decimal(10,2), it should work

 SELECT SUM(convert(decimal(10,2), Stuff)) as result FROM table

OR

 SELECT SUM(CAST(Stuff AS decimal(6,2))) as result FROM table

How to get index of an item in java.util.Set

you can extend LinkedHashSet adding your desired getIndex() method. It's 15 minutes to implement and test it. Just go through the set using iterator and counter, check the object for equality. If found, return the counter.

Garbage collector in Android

There is no need to call the garbage collector after an OutOfMemoryError.

It's Javadoc clearly states:

Thrown when the Java Virtual Machine cannot allocate an object because it is out of memory, and no more memory could be made available by the garbage collector.

So, the garbage collector already tried to free up memory before generating the error but was unsuccessful.

Detect If Browser Tab Has Focus

Surprising to see nobody mentioned document.hasFocus

if (document.hasFocus()) console.log('Tab is active')

MDN has more information.

How to check if an element is in an array

Swift

If you are not using object then you can user this code for contains.

let elements = [ 10, 20, 30, 40, 50]

if elements.contains(50) {

   print("true")

}

If you are using NSObject Class in swift. This variables is according to my requirement. you can modify for your requirement.

var cliectScreenList = [ATModelLeadInfo]()
var cliectScreenSelectedObject: ATModelLeadInfo!

This is for a same data type.

{ $0.user_id == cliectScreenSelectedObject.user_id }

If you want to AnyObject type.

{ "\($0.user_id)" == "\(cliectScreenSelectedObject.user_id)" }

Full condition

if cliectScreenSelected.contains( { $0.user_id == cliectScreenSelectedObject.user_id } ) == false {

    cliectScreenSelected.append(cliectScreenSelectedObject)

    print("Object Added")

} else {

    print("Object already exists")

 }

how to put image in center of html page?

Put your image in a container div then use the following CSS (changing the dimensions to suit your image.

.imageContainer{
        position: absolute;
        width: 100px; /*the image width*/
        height: 100px; /*the image height*/
        left: 50%;
        top: 50%;
        margin-left: -50px; /*half the image width*/
        margin-top: -50px; /*half the image height*/
    }

Multiple Inheritance in C#

I created a C# post-compiler that enables this kind of thing:

using NRoles;

public interface IFirst { void FirstMethod(); }
public interface ISecond { void SecondMethod(); }

public class RFirst : IFirst, Role {
  public void FirstMethod() { Console.WriteLine("First"); }
}

public class RSecond : ISecond, Role {
  public void SecondMethod() { Console.WriteLine("Second"); }
}

public class FirstAndSecond : Does<RFirst>, Does<RSecond> { }

You can run the post-compiler as a Visual Studio post-build-event:

C:\some_path\nroles-v0.1.0-bin\nutate.exe "$(TargetPath)"

In the same assembly you use it like this:

var fas = new FirstAndSecond();
fas.As<RFirst>().FirstMethod();
fas.As<RSecond>().SecondMethod();

In another assembly you use it like this:

var fas = new FirstAndSecond();
fas.FirstMethod();
fas.SecondMethod();

Send POST data on redirect with JavaScript/jQuery?

Here is a method, which does not use jQuery. I used it to create a bookmarklet, which checks the current page on w3-html-validator.

var f = document.createElement('form');
f.action='http://validator.w3.org/check';
f.method='POST';
f.target='_blank';

var i=document.createElement('input');
i.type='hidden';
i.name='fragment';
i.value='<!DOCTYPE html>'+document.documentElement.outerHTML;
f.appendChild(i);

document.body.appendChild(f);
f.submit();

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

In my case I was trying to run on an watchOS 7 simulator in Relese mode but the iOS 14 simulator was in Debug mode.

So simply putting both sims in Debug/Release mode solved the problem for me!

No module named pkg_resources

It was all running good in my system. The moment i used- pip install virtualenv problems started happening. Probably it broke the path to the setup files

Getting value of HTML Checkbox from onclick/onchange events

The short answer:

Use the click event, which won't fire until after the value has been updated, and fires when you want it to:

<label><input type='checkbox' onclick='handleClick(this);'>Checkbox</label>

function handleClick(cb) {
  display("Clicked, new value = " + cb.checked);
}

Live example | Source

The longer answer:

The change event handler isn't called until the checked state has been updated (live example | source), but because (as Tim Büthe points out in the comments) IE doesn't fire the change event until the checkbox loses focus, you don't get the notification proactively. Worse, with IE if you click a label for the checkbox (rather than the checkbox itself) to update it, you can get the impression that you're getting the old value (try it with IE here by clicking the label: live example | source). This is because if the checkbox has focus, clicking the label takes the focus away from it, firing the change event with the old value, and then the click happens setting the new value and setting focus back on the checkbox. Very confusing.

But you can avoid all of that unpleasantness if you use click instead.

I've used DOM0 handlers (onxyz attributes) because that's what you asked about, but for the record, I would generally recommend hooking up handlers in code (DOM2's addEventListener, or attachEvent in older versions of IE) rather than using onxyz attributes. That lets you attach multiple handlers to the same element and lets you avoid making all of your handlers global functions.


An earlier version of this answer used this code for handleClick:

function handleClick(cb) {
  setTimeout(function() {
    display("Clicked, new value = " + cb.checked);
  }, 0);
}

The goal seemed to be to allow the click to complete before looking at the value. As far as I'm aware, there's no reason to do that, and I have no idea why I did. The value is changed before the click handler is called. In fact, the spec is quite clear about that. The version without setTimeout works perfectly well in every browser I've tried (even IE6). I can only assume I was thinking about some other platform where the change isn't done until after the event. In any case, no reason to do that with HTML checkboxes.

How to watch for form changes in Angular

UPD. The answer and demo are updated to align with latest Angular.


You can subscribe to entire form changes due to the fact that FormGroup representing a form provides valueChanges property which is an Observerable instance:

this.form.valueChanges.subscribe(data => console.log('Form changes', data));

In this case you would need to construct form manually using FormBuilder. Something like this:

export class App {
  constructor(private formBuilder: FormBuilder) {
    this.form = formBuilder.group({
      firstName: 'Thomas',
      lastName: 'Mann'
    })

    this.form.valueChanges.subscribe(data => {
      console.log('Form changes', data)
      this.output = data
    })
  }
}

Check out valueChanges in action in this demo: http://plnkr.co/edit/xOz5xaQyMlRzSrgtt7Wn?p=preview

What reference do I need to use Microsoft.Office.Interop.Excel in .NET?

I had the same issue and the Microsoft.Office.Interop was not appearing in "Add Reference" option once I upgraded VS2012 to VS2015. I basically repaired the installation (Control Panel > Programs & Features > VS 2012 > Right click Change > Repair) and added the Microsoft Office component. After that the same solution started working.

Handling onchange event in HTML.DropDownList Razor MVC

The way of dknaack does not work for me, I found this solution as well:

@Html.DropDownList("Chapters", ViewBag.Chapters as SelectList, 
                    "Select chapter", new { @onchange = "location = this.value;" })

where

@Html.DropDownList(controlName, ViewBag.property + cast, "Default value", @onchange event)

In the controller you can add:

DbModel db = new DbModel();    //entity model of Entity Framework

ViewBag.Chapters = new SelectList(db.T_Chapter, "Id", "Name");

How to display alt text for an image in chrome

Yes it's an issue in webkit and also reported in chromium: http://code.google.com/p/chromium/issues/detail?id=773 It's there since 2008... and still not fixed!!

I'm using a piece of javacsript and jQuery to make my way around this.

function showAlt(){$(this).replaceWith(this.alt)};
function addShowAlt(selector){$(selector).error(showAlt).attr("src", $(selector).src)};
addShowAlt("img");

If you only want one some images:

addShowAlt("#myImgID");

File Upload using AngularJS

in simple words

in Html - add below code only

     <form name="upload" class="form" data-ng-submit="addFile()">
  <input type="file" name="file" multiple 
 onchange="angular.element(this).scope().uploadedFile(this)" />
 <button type="submit">Upload </button>
</form>

in the controller - This function is called when you click "upload file button". it will upload the file. you can console it.

$scope.uploadedFile = function(element) {
$scope.$apply(function($scope) {
  $scope.files = element.files;         
});
}

add more in controllers - below code add into the function . This function is called when you click on button which is used "hitting the api (POST)". it will send file(which uploaded) and form-data to the backend .

var url = httpURL + "/reporttojson"
        var files=$scope.files;

         for ( var i = 0; i < files.length; i++)
         {
            var fd = new FormData();
             angular.forEach(files,function(file){
             fd.append('file',file);
             });
             var data ={
              msg : message,
              sub : sub,
              sendMail: sendMail,
              selectUsersAcknowledge:false
             };

             fd.append("data", JSON.stringify(data));
              $http.post(url, fd, {
               withCredentials : false,
               headers : {
                'Content-Type' : undefined
               },
             transformRequest : angular.identity
             }).success(function(data)
             {
                  toastr.success("Notification sent successfully","",{timeOut: 2000});
                  $scope.removereport()
                   $timeout(function() {
                    location.reload();
                }, 1000);

             }).error(function(data)
             {
              toastr.success("Error in Sending Notification","",{timeOut: 2000});
              $scope.removereport()
             });
        }

in this case .. i added below code as form data

var data ={
          msg : message,
          sub : sub,
          sendMail: sendMail,
          selectUsersAcknowledge:false
         };

Download a single folder or directory from a GitHub repo

For whatever reason, the svn solution does not work for me, and since I have no need of svn for anything else, it did not make sense to spend time trying to make it, so I looked for a simple solution using tools I already had. This script uses only curl and awk to download all files in a GitHub directory described as "/:user:repo/contents/:path".

The returned body of a call to the GitHub REST API "GET /repos/:user:repo/contents/:path" command returns an object that includes a "download_url" link for each file in a directory.

This command-line script calls that REST API using curl and sends the result through AWK, which filters out all but the "download_url" lines, erases quote marks and commas from the links, and then downloads the links using another call to curl.

curl -s https://api.github.com/repos/:user/:repo/contents/:path | awk \
     '/download_url/ { gsub("\"|,", "", $2); system("curl -O "$2"); }'

Apache Spark: map vs mapPartitions?

Imp. TIP :

Whenever you have heavyweight initialization that should be done once for many RDD elements rather than once per RDD element, and if this initialization, such as creation of objects from a third-party library, cannot be serialized (so that Spark can transmit it across the cluster to the worker nodes), use mapPartitions() instead of map(). mapPartitions() provides for the initialization to be done once per worker task/thread/partition instead of once per RDD data element for example : see below.

val newRd = myRdd.mapPartitions(partition => {
  val connection = new DbConnection /*creates a db connection per partition*/

  val newPartition = partition.map(record => {
    readMatchingFromDB(record, connection)
  }).toList // consumes the iterator, thus calls readMatchingFromDB 

  connection.close() // close dbconnection here
  newPartition.iterator // create a new iterator
})

Q2. does flatMap behave like map or like mapPartitions?

Yes. please see example 2 of flatmap.. its self explanatory.

Q1. What's the difference between an RDD's map and mapPartitions

map works the function being utilized at a per element level while mapPartitions exercises the function at the partition level.

Example Scenario : if we have 100K elements in a particular RDD partition then we will fire off the function being used by the mapping transformation 100K times when we use map.

Conversely, if we use mapPartitions then we will only call the particular function one time, but we will pass in all 100K records and get back all responses in one function call.

There will be performance gain since map works on a particular function so many times, especially if the function is doing something expensive each time that it wouldn't need to do if we passed in all the elements at once(in case of mappartitions).

map

Applies a transformation function on each item of the RDD and returns the result as a new RDD.

Listing Variants

def map[U: ClassTag](f: T => U): RDD[U]

Example :

val a = sc.parallelize(List("dog", "salmon", "salmon", "rat", "elephant"), 3)
 val b = a.map(_.length)
 val c = a.zip(b)
 c.collect
 res0: Array[(String, Int)] = Array((dog,3), (salmon,6), (salmon,6), (rat,3), (elephant,8)) 

mapPartitions

This is a specialized map that is called only once for each partition. The entire content of the respective partitions is available as a sequential stream of values via the input argument (Iterarator[T]). The custom function must return yet another Iterator[U]. The combined result iterators are automatically converted into a new RDD. Please note, that the tuples (3,4) and (6,7) are missing from the following result due to the partitioning we chose.

preservesPartitioning indicates whether the input function preserves the partitioner, which should be false unless this is a pair RDD and the input function doesn't modify the keys.

Listing Variants

def mapPartitions[U: ClassTag](f: Iterator[T] => Iterator[U], preservesPartitioning: Boolean = false): RDD[U]

Example 1

val a = sc.parallelize(1 to 9, 3)
 def myfunc[T](iter: Iterator[T]) : Iterator[(T, T)] = {
   var res = List[(T, T)]()
   var pre = iter.next
   while (iter.hasNext)
   {
     val cur = iter.next;
     res .::= (pre, cur)
     pre = cur;
   }
   res.iterator
 }
 a.mapPartitions(myfunc).collect
 res0: Array[(Int, Int)] = Array((2,3), (1,2), (5,6), (4,5), (8,9), (7,8)) 

Example 2

val x = sc.parallelize(List(1, 2, 3, 4, 5, 6, 7, 8, 9,10), 3)
 def myfunc(iter: Iterator[Int]) : Iterator[Int] = {
   var res = List[Int]()
   while (iter.hasNext) {
     val cur = iter.next;
     res = res ::: List.fill(scala.util.Random.nextInt(10))(cur)
   }
   res.iterator
 }
 x.mapPartitions(myfunc).collect
 // some of the number are not outputted at all. This is because the random number generated for it is zero.
 res8: Array[Int] = Array(1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 5, 7, 7, 7, 9, 9, 10) 

The above program can also be written using flatMap as follows.

Example 2 using flatmap

val x  = sc.parallelize(1 to 10, 3)
 x.flatMap(List.fill(scala.util.Random.nextInt(10))(_)).collect

 res1: Array[Int] = Array(1, 2, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 6, 6, 6, 6, 7, 7, 7, 8, 8, 8, 8, 8, 8, 8, 8, 9, 9, 9, 9, 9, 10, 10, 10, 10, 10, 10, 10, 10) 

Conclusion :

mapPartitions transformation is faster than map since it calls your function once/partition, not once/element..

Further reading : foreach Vs foreachPartitions When to use What?

Eclipse CDT project built but "Launch Failed. Binary Not Found"

This worked for me.

Go to Project --> Properties --> Run/Debug Settings --> Click on the configuration & click "Edit", it will now open a "Edit Configuration".

Hit on "Search Project" , select the binary file from the "Binaries" and hit ok.

Note : Before doing all this, make sure you have done the below

--> Binary is generated once you execute "Build All" or (Ctrl+B)

Can't concat bytes to str

subprocess.check_output() returns bytes.

so you need to convert '\n' to bytes as well:

 f.write (plaintext + b'\n')

hope this helps

Oracle: Call stored procedure inside the package

To those that are incline to use GUI:

Click Right mouse button on procecdure name then select Test

enter image description here

Then in new window you will see script generated just add the parameters and click on Start Debugger or F9

enter image description here

Hope this saves you some time.

Gradle sync failed: failed to find Build Tools revision 24.0.0 rc1

Go to Build Gradle (Module:app) Change the following. In my case, I choose 25.0.3

android {

    compileSdkVersion 25
    buildToolsVersion "25.0.3"
    defaultConfig {
        applicationId "com.example.cesarhcq.viisolutions"
        minSdkVersion 15
        targetSdkVersion 25

After that, it works fine!

URL encoding the space character: + or %20?

This confusion is because URLs are still 'broken' to this day.

Take "http://www.google.com" for instance. This is a URL. A URL is a Uniform Resource Locator and is really a pointer to a web page (in most cases). URLs actually have a very well-defined structure since the first specification in 1994.

We can extract detailed information about the "http://www.google.com" URL:

+---------------+-------------------+
|      Part     |      Data         |
+---------------+-------------------+
|  Scheme       | http              |
|  Host         | www.google.com    |
+---------------+-------------------+

If we look at a more complex URL such as:

"https://bob:[email protected]:8080/file;p=1?q=2#third"

we can extract the following information:

+-------------------+---------------------+
|        Part       |       Data          |
+-------------------+---------------------+
|  Scheme           | https               |
|  User             | bob                 |
|  Password         | bobby               |
|  Host             | www.lunatech.com    |
|  Port             | 8080                |
|  Path             | /file;p=1           |
|  Path parameter   | p=1                 |
|  Query            | q=2                 |
|  Fragment         | third               |
+-------------------+---------------------+

https://bob:[email protected]:8080/file;p=1?q=2#third
\___/   \_/ \___/ \______________/ \__/\_______/ \_/ \___/
  |      |    |          |          |      | \_/  |    |
Scheme User Password    Host       Port  Path |   | Fragment
        \_____________________________/       | Query
                       |               Path parameter
                   Authority

The reserved characters are different for each part.

For HTTP URLs, a space in a path fragment part has to be encoded to "%20" (not, absolutely not "+"), while the "+" character in the path fragment part can be left unencoded.

Now in the query part, spaces may be encoded to either "+" (for backwards compatibility: do not try to search for it in the URI standard) or "%20" while the "+" character (as a result of this ambiguity) has to be escaped to "%2B".

This means that the "blue+light blue" string has to be encoded differently in the path and query parts:

"http://example.com/blue+light%20blue?blue%2Blight+blue".

From there you can deduce that encoding a fully constructed URL is impossible without a syntactical awareness of the URL structure.

This boils down to:

You should have %20 before the ? and + after.

Source

json and empty array

The first version is a null object while the second is an Array object with zero elements.

Null may mean here for example that no location is available for that user, no location has been requested or that some restrictions apply. Hard to tell with no reference to the API.

Add & delete view from Layout

hi if are you new in android use this way Apply your view to make it gone GONE is one way, else, get hold of the parent view, and remove the child from there..... else get the parent layout and use this method an remove all child parentView.remove(child)

I would suggest using the GONE approach...

What are differences between AssemblyVersion, AssemblyFileVersion and AssemblyInformationalVersion?

AssemblyInformationalVersion and AssemblyFileVersion are displayed when you view the "Version" information on a file through Windows Explorer by viewing the file properties. These attributes actually get compiled in to a VERSION_INFO resource that is created by the compiler.

AssemblyInformationalVersion is the "Product version" value. AssemblyFileVersion is the "File version" value.

The AssemblyVersion is specific to .NET assemblies and is used by the .NET assembly loader to know which version of an assembly to load/bind at runtime.

Out of these, the only one that is absolutely required by .NET is the AssemblyVersion attribute. Unfortunately it can also cause the most problems when it changes indiscriminately, especially if you are strong naming your assemblies.

Increasing Heap Size on Linux Machines

You can use the following code snippet :

java -XX:+PrintFlagsFinal -Xms512m -Xmx1024m -Xss512k -XX:PermSize=64m -XX:MaxPermSize=128m
    -version | grep -iE 'HeapSize|PermSize|ThreadStackSize'

In my pc I am getting following output :

    uintx InitialHeapSize                          := 536870912       {product}
    uintx MaxHeapSize                              := 1073741824      {product}
    uintx PermSize                                 := 67108864        {pd product}
    uintx MaxPermSize                              := 134217728       {pd product}
     intx ThreadStackSize                          := 512             {pd product}

How do you rebase the current branch's changes on top of changes being merged in?

Another way to look at it is to consider git rebase master as:

Rebase the current branch on top of master

Here , 'master' is the upstream branch, and that explain why, during a rebase, ours and theirs are reversed.

How to install a certificate in Xcode (preparing for app store submission)

These instructions are for XCode 6.4 (since I couldn't find the update for the recent versions even this was a bit outdated)

a) Part on the developers' website:

Sign in into: https://developer.apple.com/

Member Center

Certificates, Identifiers & Profiles

Certificates>All

Click "+" to add, and then follow the instructions. You will need to open "Keychain Access.app", there under "Keychain Access" menu > "Certificate Assistant>", choose "Request a Certificate From a Certificate Authority" etc.

b) XCode part:

After all, you need to go to XCode, and open XCode>Preferences..., choose your Apple ID > View Details... > click that rounded arrow to update as well as "+" to check for iOS Distribution or iOS Developer Signing Identities.

How do you move a file?

Transferring a file using TortoiseSVN:

Step:1 Please Select the files which you want to move, Right-click and drag the files to the folder which you to move them to, A window will popup after follow the below instruction

SVN option

Step 2: After you click the above the commit the file as below mention

SVN Commit

Method to find string inside of the text file. Then getting the following lines up to a certain limit

When you are reading the file, have you considered reading it line by line? This would allow you to check if your line contains the file as your are reading, and you could then perform whatever logic you needed based on that?

Scanner scanner = new Scanner("Student.txt");
String currentLine;

while((currentLine = scanner.readLine()) != null)
{
    if(currentLine.indexOf("Your String"))
    {
         //Perform logic
    }
}

You could use a variable to hold the line number, or you could also have a boolean indicating if you have passed the line that contains your string:

Scanner scanner = new Scanner("Student.txt");
String currentLine;
int lineNumber = 0;
Boolean passedLine = false;
while((currentLine = scanner.readLine()) != null)
{
    if(currentLine.indexOf("Your String"))
    {
         //Do task
         passedLine = true;
    }
    if(passedLine)
    {
       //Do other task after passing the line.
    }
    lineNumber++;
}

Does return stop a loop?

This code will exit the loop after the first iteration in a for of loop:

const objc = [{ name: 1 }, { name: 2 }, { name: 3 }];
for (const iterator of objc) {
  if (iterator.name == 2) {
    return;
  }
  console.log(iterator.name);// 1
}

the below code will jump on the condition and continue on a for of loop:

const objc = [{ name: 1 }, { name: 2 }, { name: 3 }];

for (const iterator of objc) {
  if (iterator.name == 2) {
    continue;
  }
  console.log(iterator.name); // 1  , 3
}

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

first, check your pillow version

python -c 'import PIL; print PIL.PILLOW_VERSION'

I use pip install --upgrade pillow upgrade the version from 2.7 to 2.9(or 3.0) fixed this.

How to leave/exit/deactivate a Python virtualenv

Simply type the following command on the command line inside the virtual environment:

deactivate

Git submodule push

A submodule is nothing but a clone of a git repo within another repo with some extra meta data (gitlink tree entry, .gitmodules file )

$ cd your_submodule
$ git checkout master
<hack,edit>
$ git commit -a -m "commit in submodule"
$ git push
$ cd ..
$ git add your_submodule
$ git commit -m "Updated submodule"

How to get datas from List<Object> (Java)?

System.out.println("Element "+i+list.get(0));}

Should be

System.out.println("Element "+i+list.get(i));}

To use the JSF tags, you give the dataList value attribute a reference to your list of elements, and the var attribute is a local name for each element of that list in turn. Inside the dataList, you use properties of the object (getters) to output the information about that individual object:

<t:dataList id="myDataList" value="#{houseControlList}" var="element" rows="3" >
...
<t:outputText id="houseId" value="#{element.houseId}"/>
...
</t:dataList>

Get number days in a specified month using JavaScript?

Date.prototype.monthDays= function(){
    var d= new Date(this.getFullYear(), this.getMonth()+1, 0);
    return d.getDate();
}

Break when a value changes using the Visual Studio debugger

You can probably make a clever use of the DebugBreak() function.

CSS: How to have position:absolute div inside a position:relative div not be cropped by an overflow:hidden on a container

If there is other content not being shown inside the outer-div (the green box), why not have that content wrapped inside another div, let's call it "content". Have overflow hidden on this new inner-div, but keep overflow visible on the green box.

The only catch is that you will then have to mess around to make sure that the content div doesn't interfere with the positioning of the red box, but it sounds like you should be able to fix that with little headache.

<div id="1" background: #efe; padding: 5px; width: 125px">
    <div id="content" style="overflow: hidden;">
    </div>
    <div id="2" style="position: relative; background: #fee; padding: 2px; width: 100px; height: 100px">
        <div id="3" style="position: absolute; top: 10px; background: #eef; padding: 2px; width: 75px; height: 150px"/>
    </div>
</div>

How to set Google Chrome in WebDriver

I'm using this since the begin and it always work. =)

System.setProperty("webdriver.chrome.driver", "C:\\pathto\\my\\chromedriver.exe");
WebDriver driver = new ChromeDriver();
driver.get("http://www.google.com");

RESTful API methods; HEAD & OPTIONS

OPTIONS tells you things such as "What methods are allowed for this resource".

HEAD gets the HTTP header you would get if you made a GET request, but without the body. This lets the client determine caching information, what content-type would be returned, what status code would be returned. The availability is only a small part of it.

.htaccess 301 redirect of single page

You could also use a RewriteRule if you wanted the ability to template match and redirect urls.

Closing database connections in Java

When you are done with using your Connection, you need to explicitly close it by calling its close() method in order to release any other database resources (cursors, handles, etc.) the connection may be holding on to.

Actually, the safe pattern in Java is to close your ResultSet, Statement, and Connection (in that order) in a finally block when you are done with them. Something like this:

Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;

try {
    // Do stuff
    ...

} catch (SQLException ex) {
    // Exception handling stuff
    ...
} finally {
    if (rs != null) {
        try {
            rs.close();
        } catch (SQLException e) { /* Ignored */}
    }
    if (ps != null) {
        try {
            ps.close();
        } catch (SQLException e) { /* Ignored */}
    }
    if (conn != null) {
        try {
            conn.close();
        } catch (SQLException e) { /* Ignored */}
    }
}

The finally block can be slightly improved into (to avoid the null check):

} finally {
    try { rs.close(); } catch (Exception e) { /* Ignored */ }
    try { ps.close(); } catch (Exception e) { /* Ignored */ }
    try { conn.close(); } catch (Exception e) { /* Ignored */ }
}

But, still, this is extremely verbose so you generally end up using an helper class to close the objects in null-safe helper methods and the finally block becomes something like this:

} finally {
    DbUtils.closeQuietly(rs);
    DbUtils.closeQuietly(ps);
    DbUtils.closeQuietly(conn);
}

And, actually, the Apache Commons DbUtils has a DbUtils class which is precisely doing that, so there isn't any need to write your own.

Calling startActivity() from outside of an Activity?

This same error I have faced in case of getting Notification in latest Android devices 9 and 10.

It depends on Launch mode how you are handling it. Use below code:- android:launchMode="singleTask"

Add this flag with Intent:- intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

Create an array with same element repeated multiple times

I had problems with the mentioned methods when I use an array like

var array = ['foo', 'bar', 'foobar'];
var filled = array.fill(7);

//filled should be ['foo', 'bar', 'foobar', 'foo', 'bar', 'foobar', 'foo']

To get this I'm using:

Array.prototype.fill = function(val){
    var l = this.length;
    if(l < val){
        for(var i = val-1-l; i >= 0; i--){
            this[i+l] = this[i % l];
        }
    }
    return this;
};

Java - Check if input is a positive integer, negative integer, natural number and so on.

(You should you as Else-If statement to check the for the three different state (positive, negative, 0)

Here is a simple example (excludes the possibility of non-integer values)

  import java.util.Scanner;

  public class Compare {

   public static void main(String[] args) { 

    Scanner input = new Scanner(System.in);

    System.out.print("Enter a number: ");
    int number = input.nextInt();

    if( number == 0)
    { System.out.println("Number is equal to zero"); }
    else if (number > 0)
    { System.out.println("Number is positive"); }
    else 
    { System.out.println("Number is negative"); }


  }
 }

What does axis in pandas mean?

I think there is an another way to understand it.

For a np.array,if we want eliminate columns we use axis = 1; if we want eliminate rows, we use axis = 0.

np.mean(np.array(np.ones(shape=(3,5,10))),axis = 0).shape # (5,10)
np.mean(np.array(np.ones(shape=(3,5,10))),axis = 1).shape # (3,10)
np.mean(np.array(np.ones(shape=(3,5,10))),axis = (0,1)).shape # (10,)

For pandas object, axis = 0 stands for row-wise operation and axis = 1 stands for column-wise operation. This is different from numpy by definition, we can check definitions from numpy.doc and pandas.doc

CSS: How to change colour of active navigation page menu

Add ID current for active/current page:

<div class="menuBar">
  <ul>
  <li id="current"><a href="index.php">HOME</a></li>
  <li><a href="two.php">PORTFOLIO</a></li>
  <li><a href="three.php">ABOUT</a></li>
  <li><a href="four.php">CONTACT</a></li>
  <li><a href="five.php">SHOP</a></li>
 </ul>

#current a { color: #ff0000; }

Auto refresh page every 30 seconds

If you want refresh the page you could use like this, but refreshing the page is usually not the best method, it better to try just update the content that you need to be updated.

javascript:

<script language="javascript">
setTimeout(function(){
   window.location.reload(1);
}, 30000);
</script>

Use of "global" keyword in Python

It means that you should not do the following:

x = 1

def myfunc():
  global x

  # formal parameter
  def localfunction(x):
    return x+1

  # import statement
  import os.path as x

  # for loop control target
  for x in range(10):
    print x

  # class definition
  class x(object):
    def __init__(self):
      pass

  #function definition
  def x():
    print "I'm bad"

Excel VBA Open a Folder

I use this to open a workbook and then copy that workbook's data to the template.

Private Sub CommandButton24_Click()
Set Template = ActiveWorkbook
 With Application.FileDialog(msoFileDialogOpen)
    .InitialFileName = "I:\Group - Finance" ' Yu can select any folder you want
    .Filters.Clear
    .Title = "Your Title"
    If Not .Show Then
        MsgBox "No file selected.": Exit Sub
    End If
    Workbooks.OpenText .SelectedItems(1)

'The below is to copy the file into a new sheet in the workbook and paste those values in sheet 1

    Set myfile = ActiveWorkbook
    ActiveWorkbook.Sheets(1).Copy after:=ThisWorkbook.Sheets(1)
    myfile.Close
    Template.Activate
    ActiveSheet.Cells.Select
    Selection.Copy
    Sheets("Sheet1").Select
    Cells.Select
    ActiveSheet.Paste

End With

Java, List only subdirectories from a directory, not files

I'd like to use the java.io.File functionality,

In 2012 (date of the question) yes, not today. java.nio API has to be favored for such requirements.

Terrible with so many answers, but not the simple way that I would use that is Files.walk().filter().collect().

Globally two approaches are possible :

1)Files.walk(Path start, ) has no maxDepth limitations while

2)Files.walk(Path start, int maxDepth, FileVisitOption... options) allows to set it.

Without specifying any depth limitation, it would give :

Path directory = Paths.get("/foo/bar");

try {
    List<Path> directories =
            Files.walk(directory)
                 .filter(Files::isDirectory)
                 .collect(Collectors.toList());
} catch (IOException e) {
    // process exception
}

And if for legacy reasons, you need to get a List of File you can just add a map(Path::toFile) operation before the collect :

Path directory = Paths.get("/foo/bar");

try {
    List<File> directories =
            Files.walk(directory)
                 .filter(Files::isDirectory)
                 .map(Path::toFile)
                 .collect(Collectors.toList());
} catch (IOException e) {
    // process exception
}

react-router go back a page how do you configure history?

In react-router v4.x you can use history.goBack which is equivalent to history.go(-1).

App.js

import React from "react";
import { render } from "react-dom";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";
import Home from "./Home";
import About from "./About";
import Contact from "./Contact";
import Back from "./Back";

const styles = {
  fontFamily: "sans-serif",
  textAlign: "left"
};

const App = () => (
  <div style={styles}>
    <Router>
      <div>
        <ul>
          <li><Link to="/">Home</Link></li>
          <li><Link to="/about">About</Link></li>
          <li><Link to="/contact">Contact</Link></li>
        </ul>

        <hr />

        <Route exact path="/" component={Home} />
        <Route path="/about" component={About} />
        <Route path="/contact" component={Contact} />

        <Back />{/* <----- This is component that will render Back button */}
      </div>
    </Router>
  </div>
);

render(<App />, document.getElementById("root"));

Back.js

import React from "react";
import { withRouter } from "react-router-dom";

const Back = ({ history }) => (
  <button onClick={history.goBack}>Back to previous page</button>
);

export default withRouter(Back);

Demo: https://codesandbox.io/s/ywmvp95wpj

Please remember that by using history your users can leave because history.goBack() can load a page that visitor has visited before opening your application.


To prevent such situation as described above, I've created a simple library react-router-last-location that watch your users last location.

Usage is very straight forward. First you need to install react-router-dom and react-router-last-location from npm.

npm install react-router-dom react-router-last-location --save

Then use LastLocationProvider as below:

App.js

import React from "react";
import { render } from "react-dom";
import { BrowserRouter as Router, Route, Link } from "react-router-dom";
import { LastLocationProvider } from "react-router-last-location";
//              ?
//              |
//              |
//
//       Import provider
//
import Home from "./Home";
import About from "./About";
import Contact from "./Contact";
import Back from "./Back";

const styles = {
  fontFamily: "sans-serif",
  textAlign: "left"
};

const App = () => (
  <div style={styles}>
    <h5>Click on About to see your last location</h5>
    <Router>
      <LastLocationProvider>{/* <---- Put provider inside <Router> */}
        <div>
          <ul>
            <li><Link to="/">Home</Link></li>
            <li><Link to="/about">About</Link></li>
            <li><Link to="/contact">Contact</Link></li>
          </ul>

          <hr />

          <Route exact path="/" component={Home} />
          <Route path="/about" component={About} />
          <Route path="/contact" component={Contact} />

          <Back />
        </div>
      </LastLocationProvider>
    </Router>
  </div>
);

render(<App />, document.getElementById("root"));

Back.js

import React from "react";
import { Link } from "react-router-dom";
import { withLastLocation } from "react-router-last-location";
//              ?
//              |
//              |
//
//    `withLastLocation` higher order component
//    will pass `lastLocation` to your component               
//
//                   |
//                   |
//                   ?
const Back = ({ lastLocation }) => (
  lastLocation && <Link to={lastLocation || '/'}>Back to previous page</Link>
);


//          Remember to wrap
//   your component before exporting
//
//                   |
//                   |
//                   ?
export default withLastLocation(Back);

Demo: https://codesandbox.io/s/727nqm99jj

How to remove unused dependencies from composer?

In fact, it is very easy.

composer update

will do all this for you, but it will also update the other packages.

To remove a package without updating the others, specifiy that package in the command, for instance:

composer update monolog/monolog

will remove the monolog/monolog package.

Nevertheless, there may remain some empty folders or files that cannot be removed automatically, and that have to be removed manually.

Check if the file exists using VBA

Function FileExists(fullFileName As String) As Boolean
    FileExists = VBA.Len(VBA.Dir(fullFileName)) > 0
End Function

Sleep function in C++

Prior to C++11, there was no portable way to do this.

A portable way is to use Boost or Ace library. There is ACE_OS::sleep(); in ACE.

MVC3 DropDownListFor - a simple example?

You should do like this:

@Html.DropDownListFor(m => m.ContribType, 
                new SelectList(Model.ContribTypeOptions, 
                               "ContribId", "Value"))

Where:

m => m.ContribType

is a property where the result value will be.

How to get Database Name from Connection String using SqlConnectionStringBuilder

You can use InitialCatalog Property or builder["Database"] works as well. I tested it with different case and it still works.

Drawing an image from a data URL to a canvas

function drawDataURIOnCanvas(strDataURI, canvas) {
    "use strict";
    var img = new window.Image();
    img.addEventListener("load", function () {
        canvas.getContext("2d").drawImage(img, 0, 0);
    });
    img.setAttribute("src", strDataURI);
}

Django template how to look up a dictionary value with a variable

env: django 2.1.7

view:

dict_objs[query_obj.id] = {'obj': query_obj, 'tag': str_tag}
return render(request, 'obj.html', {'dict_objs': dict_objs})

template:

{% for obj_id,dict_obj in dict_objs.items %}
<td>{{ dict_obj.obj.obj_name }}</td>
<td style="display:none">{{ obj_id }}</td>
<td>{{ forloop.counter }}</td>
<td>{{ dict_obj.obj.update_timestamp|date:"Y-m-d H:i:s"}}</td>

How can I detect window size with jQuery?

You cannot really find the display resolution from a web page. There is a CSS Media Queries statement for it, but it is poorly implemented in most devices and browsers, if at all. However, you do not need to know the resolution of the display, because changing it causes the (pixel) width of the window to change, which can be detected using the methods others have described:

$(window).resize(function() {
  // This will execute whenever the window is resized
  $(window).height(); // New height
  $(window).width(); // New width
});

You can also use CSS Media Queries in browsers that support them to adapt your page's style to various display widths, but you should really be using em units and percentages and min-width and max-width in your CSS if you want a proper flexible layout. Gmail probably uses a combination of all these.

Returning the product of a list

One option is to use numba and the @jit or @njit decorator. I also made one or two little tweaks to your code (at least in Python 3, "list" is a keyword that shouldn't be used for a variable name):

@njit
def njit_product(lst):
    p = lst[0]  # first element
    for i in lst[1:]:  # loop over remaining elements
        p *= i
    return p

For timing purposes, you need to run once to compile the function first using numba. In general, the function will be compiled the first time it is called, and then called from memory after that (faster).

njit_product([1, 2])  # execute once to compile

Now when you execute your code, it will run with the compiled version of the function. I timed them using a Jupyter notebook and the %timeit magic function:

product(b)  # yours
# 32.7 µs ± 510 ns per loop (mean ± std. dev. of 7 runs, 10000 loops each)

njit_product(b)
# 92.9 µs ± 392 ns per loop (mean ± std. dev. of 7 runs, 10000 loops each)

Note that on my machine, running Python 3.5, the native Python for loop was actually the fastest. There may be a trick here when it comes to measuring numba-decorated performance with Jupyter notebooks and the %timeit magic function. I am not sure that the timings above are correct, so I recommend trying it out on your system and seeing if numba gives you a performance boost.

error: unknown type name ‘bool’

C90 does not support the boolean data type.

C99 does include it with this include:

#include <stdbool.h>

How to reference a .css file on a razor view?

layout works the same as an master page. any css reference that layout has, any child pages will have.

Scott Gu has an excellent explanation here

SQL: IF clause within WHERE clause

In sql server I had same problem I wanted to use an and statement only if parameter is false and on true I had to show both values true and false so I used it this way

(T.IsPublic = @ShowPublic or  @ShowPublic = 1)

How can I determine if a .NET assembly was built for x86 or x64?

Just for clarification, CorFlags.exe is part of the .NET Framework SDK. I have the development tools on my machine, and the simplest way for me determine whether a DLL is 32-bit only is to:

  1. Open the Visual Studio Command Prompt (In Windows: menu Start/Programs/Microsoft Visual Studio/Visual Studio Tools/Visual Studio 2008 Command Prompt)

  2. CD to the directory containing the DLL in question

  3. Run corflags like this: corflags MyAssembly.dll

You will get output something like this:

Microsoft (R) .NET Framework CorFlags Conversion Tool.  Version  3.5.21022.8
Copyright (c) Microsoft Corporation.  All rights reserved.

Version   : v2.0.50727
CLR Header: 2.5
PE        : PE32
CorFlags  : 3
ILONLY    : 1
32BIT     : 1
Signed    : 0

As per comments the flags above are to be read as following:

  • Any CPU: PE = PE32 and 32BIT = 0
  • x86: PE = PE32 and 32BIT = 1
  • 64-bit: PE = PE32+ and 32BIT = 0

java.util.regex - importance of Pattern.compile()?

Compile parses the regular expression and builds an in-memory representation. The overhead to compile is significant compared to a match. If you're using a pattern repeatedly it will gain some performance to cache the compiled pattern.

Getting 400 bad request error in Jquery Ajax POST

You need to build query from "data" object using the following function

function buildQuery(obj) {
        var Result= '';
        if(typeof(obj)== 'object') {
            jQuery.each(obj, function(key, value) {
                Result+= (Result) ? '&' : '';
                if(typeof(value)== 'object' && value.length) {
                    for(var i=0; i<value.length; i++) {
                        Result+= [key+'[]', encodeURIComponent(value[i])].join('=');
                    }
                } else {
                    Result+= [key, encodeURIComponent(value)].join('=');
                }
            });
        }
        return Result;
    }

and then proceed with

var data= {
"subject:title":"Test Name",
"subject:description":"Creating test subject to check POST method API",
"sub:tags": ["facebook:work, facebook:likes"],
"sampleSize" : 10,
"values": ["science", "machine-learning"]
}

$.ajax({
  type: 'POST',
  url: "http://localhost:8080/project/server/rest/subjects",
  data: buildQuery(data),
  error: function(e) {
    console.log(e);
  }
});

How do I perform an insert and return inserted identity with Dapper?

There is a great library to make your life easier Dapper.Contrib.Extensions. After including this you can just write:

public int Add(Transaction transaction)
{
        using (IDbConnection db = Connection)
        {
                return (int)db.Insert(transaction);
        }
}

How To have Dynamic SQL in MySQL Stored Procedure

I don't believe MySQL supports dynamic sql. You can do "prepared" statements which is similar, but different.

Here is an example:

mysql> PREPARE stmt FROM 
    -> 'select count(*) 
    -> from information_schema.schemata 
    -> where schema_name = ? or schema_name = ?'
;
Query OK, 0 rows affected (0.00 sec)
Statement prepared
mysql> EXECUTE stmt 
    -> USING @schema1,@schema2
+----------+
| count(*) |
+----------+
|        2 |
+----------+
1 row in set (0.00 sec)
mysql> DEALLOCATE PREPARE stmt;

The prepared statements are often used to see an execution plan for a given query. Since they are executed with the execute command and the sql can be assigned to a variable you can approximate the some of the same behavior as dynamic sql.

Here is a good link about this:

Don't forget to deallocate the stmt using the last line!

Good Luck!

How to create large PDF files (10MB, 50MB, 100MB, 200MB, 500MB, 1GB, etc.) for testing purposes?

The most simple tool: use pdftk (or pdftk.exe, if you are on Windows):

pdftk 10_MB.pdf 100_MB.pdf cat output 110_MB.pdf

This will be a valid PDF. Download pdftk here.

Update: if you want really large (and valid!), non-optimized PDFs, use this command:

pdftk 100MB.pdf 100MB.pdf 100MB.pdf 100MB.pdf 100MB.pdf cat output 500_MB.pdf

or even (if you are on Linux, Unix or Mac OS X):

pdftk $(for i in $(seq 1 100); do echo -n "100MB.pdf "; done) cat output 10_GB.pdf

Browser: Identifier X has already been declared

The problem solved when I don't use any declaration like var, let or const

2D character array initialization in C

char **options[2][100];

declares a size-2 array of size-100 arrays of pointers to pointers to char. You'll want to remove one *. You'll also want to put your string literals in double quotes.

Non-conformable arrays error in code

The problem is that omega in your case is matrix of dimensions 1 * 1. You should convert it to a vector if you wish to multiply t(X) %*% X by a scalar (that is omega)

In particular, you'll have to replace this line:

omega   = rgamma(1,a0,1) / L0

with:

omega   = as.vector(rgamma(1,a0,1) / L0)

everywhere in your code. It happens in two places (once inside the loop and once outside). You can substitute as.vector(.) or c(t(.)). Both are equivalent.

Here's the modified code that should work:

gibbs = function(data, m01 = 0, m02 = 0, k01 = 0.1, k02 = 0.1, 
                     a0 = 0.1, L0 = 0.1, nburn = 0, ndraw = 5000) {
    m0      = c(m01, m02) 
    C0      = matrix(nrow = 2, ncol = 2) 
    C0[1,1] = 1 / k01 
    C0[1,2] = 0 
    C0[2,1] = 0 
    C0[2,2] = 1 / k02 
    beta    = mvrnorm(1,m0,C0) 
    omega   = as.vector(rgamma(1,a0,1) / L0)
    draws   = matrix(ncol = 3,nrow = ndraw) 
    it      = -nburn 

    while (it < ndraw) {
        it    = it + 1 
        C1    = solve(solve(C0) + omega * t(X) %*% X) 
        m1    = C1 %*% (solve(C0) %*% m0 + omega * t(X) %*% y)
        beta  = mvrnorm(1, m1, C1) 
        a1    = a0 + n / 2 
        L1    = L0 + t(y - X %*% beta) %*% (y - X %*% beta) / 2 
        omega = as.vector(rgamma(1, a1, 1) / L1)
        if (it > 0) { 
            draws[it,1] = beta[1]
            draws[it,2] = beta[2]
            draws[it,3] = omega
        }
    }
    return(draws)
}

Convert unix time stamp to date in java

Java 8 introduces the Instant.ofEpochSecond utility method for creating an Instant from a Unix timestamp, this can then be converted into a ZonedDateTime and finally formatted, e.g.:

final DateTimeFormatter formatter = 
    DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

final long unixTime = 1372339860;
final String formattedDtm = Instant.ofEpochSecond(unixTime)
        .atZone(ZoneId.of("GMT-4"))
        .format(formatter);

System.out.println(formattedDtm);   // => '2013-06-27 09:31:00'

I thought this might be useful for people who are using Java 8.

How to use concerns in Rails 4

It's worth to mention that using concerns is considered bad idea by many.

  1. like this guy
  2. and this one

Some reasons:

  1. There is some dark magic happening behind the scenes - Concern is patching include method, there is a whole dependency handling system - way too much complexity for something that's trivial good old Ruby mixin pattern.
  2. Your classes are no less dry. If you stuff 50 public methods in various modules and include them, your class still has 50 public methods, it's just that you hide that code smell, sort of put your garbage in the drawers.
  3. Codebase is actually harder to navigate with all those concerns around.
  4. Are you sure all members of your team have same understanding what should really substitute concern?

Concerns are easy way to shoot yourself in the leg, be careful with them.

How do I do string replace in JavaScript to convert ‘9.61’ to ‘9:61’?

Do it like this:

var value = $("#text").val(); // value = 9.61 use $("#text").text() if you are not on select box...
value = value.replace(".", ":"); // value = 9:61
// can then use it as
$("#anothertext").val(value);

Updated to reflect to current version of jQuery. And also there are a lot of answers here that would best fit to any same situation as this. You, as a developer, need to know which is which.

Replace all occurrences

To replace multiple characters at a time use some thing like this: name.replace(/&/g, "-"). Here I am replacing all & chars with -. g means "global"

Note - you may need to add square brackets to avoid an error - title.replace(/[+]/g, " ")

credits vissu and Dante Cullari

Convert Python dictionary to JSON array

If you use Python 2, don't forget to add the UTF-8 file encoding comment on the first line of your script.

# -*- coding: UTF-8 -*-

This will fix some Unicode problems and make your life easier.

Getting value of selected item in list box as string

If you want to retrieve your value from an list box you should try this:

String itemSelected = numberListBox.GetItemText(numberListBox.SelectedItem);

Meaning of = delete after function declaration

  1. = 0 means that a function is pure virtual and you cannot instantiate an object from this class. You need to derive from it and implement this method
  2. = delete means that the compiler will not generate those constructors for you. AFAIK this is only allowed on copy constructor and assignment operator. But I am not too good at the upcoming standard.

Plain Old CLR Object vs Data Transfer Object

Don't even call them DTOs. They're called Models....Period. Models never have behavior. I don't know who came up with this dumb term DTO but it must be a .NET thing is all I can figure. Think of view models in MVC, same dam** thing, models are used to transfer state between layers server side or over the wire period, they are all models. Properties with data. These are models you pass ove the wire. Models, Models Models. That's it.

I wish the stupid term DTO would go away from our vocabulary.

How to detect when facebook's FB.init is complete

Another way to check if FB has initialized is by using the following code:

ns.FBInitialized = function () {
    return typeof (FB) != 'undefined' && window.fbAsyncInit.hasRun;
};

Thus in your page ready event you could check ns.FBInitialized and defer the event to later phase by using setTimeOut.

qmake: could not find a Qt installation of ''

For my Qt 5.7, open QtCreator, go to Tools -> Options -> Build & Run -> Qt Versions gave me the location of qmake.

What is the $$hashKey added to my JSON.stringify result

Angular adds this to keep track of your changes, so it knows when it needs to update the DOM.

If you use angular.toJson(obj) instead of JSON.stringify(obj) then Angular will strip out these internal-use values for you.

Also, if you change your repeat expression to use the track by {uniqueProperty} suffix, Angular won't have to add $$hashKey at all. For example

<ul>
    <li ng-repeat="link in navLinks track by link.href">
        <a ng-href="link.href">{{link.title}}</a>
    </li>
</ul>

Just always remember you need the "link." part of the expression - I always tend to forget that. Just track by href will surely not work.

JAVA_HOME is set to an invalid directory:

You need to set with only C:\Program Files\Java\jdk1.8.0_12.

And check with using new cmd. It will be updated

List<Map<String, String>> vs List<? extends Map<String, String>>

The difference is that, for example, a

List<HashMap<String,String>>

is a

List<? extends Map<String,String>>

but not a

List<Map<String,String>>

So:

void withWilds( List<? extends Map<String,String>> foo ){}
void noWilds( List<Map<String,String>> foo ){}

void main( String[] args ){
    List<HashMap<String,String>> myMap;

    withWilds( myMap ); // Works
    noWilds( myMap ); // Compiler error
}

You would think a List of HashMaps should be a List of Maps, but there's a good reason why it isn't:

Suppose you could do:

List<HashMap<String,String>> hashMaps = new ArrayList<HashMap<String,String>>();

List<Map<String,String>> maps = hashMaps; // Won't compile,
                                          // but imagine that it could

Map<String,String> aMap = Collections.singletonMap("foo","bar"); // Not a HashMap

maps.add( aMap ); // Perfectly legal (adding a Map to a List of Maps)

// But maps and hashMaps are the same object, so this should be the same as

hashMaps.add( aMap ); // Should be illegal (aMap is not a HashMap)

So this is why a List of HashMaps shouldn't be a List of Maps.

Editable 'Select' element

Thanks to @Arraxas's anwser, I customized the arrow and make the input element auto-adaptive to the select element, and it looks good on Chrome, Firefox of my Android mobile phone (set color:transparent for select and some color for option to hide text display of the select because the input and .combobox div:after cannot completely cover select).

_x000D_
_x000D_
/* https://stackoverflow.com/questions/13694271/modify-select-so-only-the-first-one-is-gray/41941056#41941056
select option:first-child, */
.combobox select, .combobox select option { color: #000000; }
.combobox select:invalid, .combobox select option[value=""] { color:grey; }

.combobox {position:absolute; left:80px; top:6px;}
.combobox>div { position:relative; font-size:1em; }
.combobox select {
    font-size:inherit; color:transparent;
    padding:0; -moz-appearance:none; -webkit-appearance:none; appearance:none;
    border:1px solid blueviolet;
}
.combobox input {
    position:absolute;top:1px;left:0px; text-overflow:ellipsis;
    box-sizing:border-box; padding:0px; margin:0px; height:calc(100% - 1px); width:calc(100% - 20px);
    border:1px solid blueviolet; border-right:none; border-top:none;
}
.combobox>div:after{
    position:absolute; top:0px; right:0px; height:100%; width:20px;
    box-sizing:border-box; content:"?"; border:1px solid blueviolet; pointer-events:none;
    display:flex; flex-direction:row; align-items:center; justify-content:center;
}
.combobox select:focus, .combobox input:focus {outline:none;}
_x000D_
<!-- mandatory benefits/social security/welfare -->
<div class="combobox"><div>
    <select id=MandatoryBenefits onchange="this.nextElementSibling.value=this.value" required>
        <option value="" selected>Select ...</option>
        <option value="Pension">Pension %</option>
        <option value="Medical">Medical %</option>
        <option value="Unemployment">Unemployment %</option>
        <option value="Injury">Injury %</option>
        <option value="Maternity">Maternity %</option>
        <option value="Serious Illness">Serious Illness %</option>
        <option value="Housing Fund">Housing Fund %</option>
    </select>
    <input type="text" value="" onchange="this.previousElementSibling.selectedIndex=0"
        oninput="this.previousElementSibling.options[0].value=this.value; this.previousElementSibling.options[0].innerHTML=this.value" />
</div></div>
_x000D_
_x000D_
_x000D_

online demo (@jsbin)

HTML5 Video Autoplay not working correctly

Chrome does not allow autoplay if the video is not muted. Try using this:

<video width="440px" loop="true" autoplay="autoplay" controls muted>
  <source src="http://www.tuscorlloyds.com/CorporateVideo.mp4" type="video/mp4" />
  <source src="http://www.tuscorlloyds.com/CorporateVideo.ogv" type="video/ogv" />
  <source src="http://www.tuscorlloyds.com/CorporateVideo.webm" type="video/webm" />
</video>

anchor jumping by using javascript

Not enough rep for a comment.

The getElementById() based method in the selected answer won't work if the anchor has name but not id set (which is not recommended, but does happen in the wild).

Something to bare in mind if you don't have control of the document markup (e.g. webextension).

The location based method in the selected answer can also be simplified with location.replace:

function jump(hash) { location.replace("#" + hash) }

Xampp localhost/dashboard

Here's what's actually happening localhost means that you want to open htdocs. First it will search for any file named index.php or index.html. If one of those exist it will open the file. If neither of those exist then it will open all folder/file inside htdocs directory which is what you want.

So, the simplest solution is to rename index.php or index.html to index2.php etc.

How does one output bold text in Bash?

The most compatible way of doing this is using tput to discover the right sequences to send to the terminal:

bold=$(tput bold)
normal=$(tput sgr0)

then you can use the variables $bold and $normal to format things:

echo "this is ${bold}bold${normal} but this isn't"

gives

this is bold but this isn't

How to comment multiple lines in Visual Studio Code?

First, select the lines you want to comment/uncomment (CTRL+L is convenient to select a few lines)

Then:

  • To toggle line comments, execute editor.action.commentLine (CTRL+/ on Windows)

    or

  • To add line comments, execute editor.action.addCommentLine (CTRL+K CTRL+C)

    To remove line comments, execute editor.action.removeCommentLine (CTRL+K CTRL+U)

    or

  • To toggle a block comment, execute editor.action.blockComment (SHIFT-ALT-A)

See the official doc : Key Bindings for Visual Studio Code

javascript - Create Simple Dynamic Array

var arr = [];
for(var i=1; i<=mynumber; i++) {
   arr.push(i.toString());
}

is there a tool to create SVG paths from an SVG file?

Gimp can be used to convert SVGs with primitives (e.g. rects, circles, etc.) into a single path which can be used within HTML5.

  1. First download Gimp: https://www.gimp.org/downloads/
  2. Export your SVG as a .svg file with any tool of choice e.g. Illustrator. Don't worry if the SVG output is messy for now, Gimp will clean it up
  3. Import the SVG file into Gimp with File -> Open, and the following (or similar) dialog should show up:

Gimp SVG Open Dialog

Check both the Import Paths and Merge imported paths options

  1. Then go to Windows->Dockable Dialogues->Paths
  2. Right-click on the single path which says Imported Path and you should see the following dialog:

enter image description here

  1. Click Export Path... and save this text file to a location of your choice
  2. Locate and open up this file with a text editor of your choice e.g Notepad, TextEdit
  3. Copy the text within the <path d="copy this text here" />
  4. Since Gimp formats the text with lots of spaces, you may need to re-format it, by removing some of the spaces to paste it into your HTML in a single line

increment date by one month

Use DateTime::add.

$start = new DateTime("2010-12-11", new DateTimeZone("UTC"));
$month_later = clone $start;
$month_later->add(new DateInterval("P1M"));

I used clone because add modifies the original object, which might not be desired.

Install / upgrade gradle on Mac OS X

Another alternative is to use sdkman. An advantage of sdkman over brew is that many versions of gradle are supported. (brew only supports the latest version and 2.14.) To install sdkman execute:

curl -s "https://get.sdkman.io" | bash

Then follow the instructions. Go here for more installation information. Once sdkman is installed use the command:

sdk install gradle

Or to install a specific version:

sdk install gradle 2.2

Or use to use a specific installed version:

sdk use gradle 2.2

To see which versions are installed and available:

sdk list gradle

For more information go here.

pip: no module named _internal

For the current user only:

easy_install --user pip

or

python -m pip install --upgrade --user pip

The second may give /usr/bin/python: No module named pip Even if which pip finds the module named pip. In this case try the easy_install

The import org.junit cannot be resolved

If you use maven and this piece of code is located in the main folder, try relocating it to the test folder.

How to use glyphicons in bootstrap 3.0

If you are using grunt to build your application, it's possible that during build the paths change. In this case you need to modify your grunt file like this:

copy: {
        main: {
            files: [{
                src: ['fonts/**'],
                dest: 'dist/fonts/',
                filter: 'isFile',
                expand: true,
                flatten: true
            }, {
                src: ['bower_components/font-awesome/fonts/**'],
                dest: 'dist/css/',
                filter: 'isFile',
                expand: true,
                flatten: false
            }]
        }
    },

Laravel Mail::send() sending to multiple to or bcc addresses

the accepted answer does not work any longer with laravel 5.3 because mailable tries to access ->email and results in

ErrorException in Mailable.php line 376: Trying to get property of non-object

a working code for laravel 5.3 is this:

$users_temp = explode(',', '[email protected],[email protected]');
    $users = [];
    foreach($users_temp as $key => $ut){
      $ua = [];
      $ua['email'] = $ut;
      $ua['name'] = 'test';
      $users[$key] = (object)$ua;
    }
 Mail::to($users)->send(new OrderAdminSendInvoice($o));

Is either GET or POST more secure than the other?

The GET request is marginally less secure than the POST request. Neither offers true "security" by itself; using POST requests will not magically make your website secure against malicious attacks by a noticeable amount. However, using GET requests can make an otherwise secure application insecure.

The mantra that you "must not use GET requests to make changes" is still very much valid, but this has little to do with malicious behaviour. Login forms are the ones most sensitive to being sent using the wrong request type.

Search spiders and web accelerators

This is the real reason you should use POST requests for changing data. Search spiders will follow every link on your website, but will not submit random forms they find.

Web accelerators are worse than search spiders, because they run on the client’s machine, and "click" all links in the context of the logged in user. Thus, an application that uses a GET request to delete stuff, even if it requires an administrator, will happily obey the orders of the (non-malicious!) web accelerator and delete everything it sees.

Confused deputy attack

A confused deputy attack (where the deputy is the browser) is possible regardless of whether you use a GET or a POST request.

On attacker-controlled websites GET and POST are equally easy to submit without user interaction.

The only scenario in which POST is slightly less susceptible is that many websites that aren’t under the attacker’s control (say, a third-party forum) allow embedding arbitrary images (allowing the attacker to inject an arbitrary GET request), but prevent all ways of injecting an arbitary POST request, whether automatic or manual.

One might argue that web accelerators are an example of confused deputy attack, but that’s just a matter of definition. If anything, a malicious attacker has no control over this, so it’s hardly an attack, even if the deputy is confused.

Proxy logs

Proxy servers are likely to log GET URLs in their entirety, without stripping the query string. POST request parameters are not normally logged. Cookies are unlikely to be logged in either case. (example)

This is a very weak argument in favour of POST. Firstly, un-encrypted traffic can be logged in its entirety; a malicious proxy already has everything it needs. Secondly, the request parameters are of limited use to an attacker: what they really need is the cookies, so if the only thing they have are proxy logs, they are unlikely to be able to attack either a GET or a POST URL.

There is one exception for login requests: these tend to contain the user’s password. Saving this in the proxy log opens up a vector of attack that is absent in the case of POST. However, login over plain HTTP is inherently insecure anyway.

Proxy cache

Caching proxies might retain GET responses, but not POST responses. Having said that, GET responses can be made non-cacheable with less effort than converting the URL to a POST handler.

HTTP "Referer"

If the user were to navigate to a third party website from the page served in response to a GET request, that third party website gets to see all the GET request parameters.

Belongs to the category of "reveals request parameters to a third party", whose severity depends on what is present in those parameters. POST requests are naturally immune to this, however to exploit the GET request a hacker would need to insert a link to their own website into the server’s response.

Browser history

This is very similar to the "proxy logs" argument: GET requests are stored in the browser history along with their parameters. The attacker can easily obtain these if they have physical access to the machine.

Browser refresh action

The browser will retry a GET request as soon as the user hits "refresh". It might do that when restoring tabs after shutdown. Any action (say, a payment) will thus be repeated without warning.

The browser will not retry a POST request without a warning.

This is a good reason to use only POST requests for changing data, but has nothing to do with malicious behaviour and, hence, security.

So what should I do?

  • Use only POST requests to change data, mainly for non-security-related reasons.
  • Use only POST requests for login forms; doing otherwise introduces attack vectors.
  • If your site performs sensitive operations, you really need someone who knows what they’re doing, because this can’t be covered in a single answer. You need to use HTTPS, HSTS, CSP, mitigate SQL injection, script injection (XSS), CSRF, and a gazillion of other things that may be specific to your platform (like the mass assignment vulnerability in various frameworks: ASP.NET MVC, Ruby on Rails, etc.). There is no single thing that will make the difference between "secure" (not exploitable) and "not secure".

Over HTTPS, POST data is encoded, but could URLs be sniffed by a 3rd party?

No, they can’t be sniffed. But the URLs will be stored in the browser history.

Would it be fair to say the best practice is to avoid possible placing sensitive data in the POST or GET altogether and using server side code to handle sensitive information instead?

Depends on how sensitive it is, or more specifically, in what way. Obviously the client will see it. Anyone with physical access to the client’s computer will see it. The client can spoof it when sending it back to you. If those matter then yes, keep the sensitive data on the server and don’t let it leave.

How to get the element clicked (for the whole document)?

You need to use the event.target which is the element which originally triggered the event. The this in your example code refers to document.

In jQuery, that's...

$(document).click(function(event) {
    var text = $(event.target).text();
});

Without jQuery...

document.addEventListener('click', function(e) {
    e = e || window.event;
    var target = e.target || e.srcElement,
        text = target.textContent || target.innerText;   
}, false);

Also, ensure if you need to support < IE9 that you use attachEvent() instead of addEventListener().

MySQL root access from all hosts

Update the bind-address = 0.0.0.0 in the /etc/mysql/mysql.conf.d/mysqld.cnf and from the mysql command line allow the root user to connect from any Ip.

Below was the only commands worked for mysql-8.0 as other were failing with error syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'IDENTIFIED BY 'abcd'' at line 1

GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost';
UPDATE mysql.user SET host='%' WHERE user='root';

Restart the mysql client

sudo service mysql restart

What is the difference between :focus and :active?

Using "focus" will give keyboard users the same effect that mouse users get when they hover with a mouse. "Active" is needed to get the same effect in Internet Explorer.

The reality is, these states do not work as they should for all users. Not using all three selectors creates accessibility issues for many keyboard-only users who are physically unable to use a mouse. I invite you to take the #nomouse challenge (nomouse dot org).

Concatenating Matrices in R

Sounds like you're looking for rbind:

> a<-matrix(nrow=10,ncol=5)
> b<-matrix(nrow=20,ncol=5)
> dim(rbind(a,b))
[1] 30  5

Similarly, cbind stacks the matrices horizontally.

I am not entirely sure what you mean by the last question ("Can I do this for matrices of different rows and columns.?")

How do I scroll to an element within an overflowed Div?

I've adjusted Glenn Moss' answer to account for the fact that overflow div might not be at the top of the page.

parentDiv.scrollTop(parentDiv.scrollTop() + (innerListItem.position().top - parentDiv.position().top) - (parentDiv.height()/2) + (innerListItem.height()/2)  )

I was using this on a google maps application with a responsive template. On resolution > 800px, the list was on the left side of the map. On resolution < 800 the list was below the map.

Concatenate two char* strings in a C program

strcat concats str2 onto str1

You'll get runtime errors because str1 is not being properly allocated for concatenation

How to insert data into elasticsearch

I started off using curl, but since have migrated to use kibana. Here is some more information on the ELK stack from elastic.co (E elastic search, K kibana): https://www.elastic.co/elk-stack

With kibana your POST requests are a bit more simple:

POST /<INDEX_NAME>/<TYPE_NAME>
{
    "field": "value",
    "id": 1,
    "account_id": 213,
    "name": "kimchy"
}

When should an IllegalArgumentException be thrown?

Throwing runtime exceptions "sparingly" isn't really a good policy -- Effective Java recommends that you use checked exceptions when the caller can reasonably be expected to recover. (Programmer error is a specific example: if a particular case indicates programmer error, then you should throw an unchecked exception; you want the programmer to have a stack trace of where the logic problem occurred, not to try to handle it yourself.)

If there's no hope of recovery, then feel free to use unchecked exceptions; there's no point in catching them, so that's perfectly fine.

It's not 100% clear from your example which case this example is in your code, though.

How to show disable HTML select option in by default?

If you are using jQuery to fill your select element, you can use this:

html

<select id="tagging"></select>

js

array_of_options = ['Choose Tagging', 'Option A', 'Option B', 'Option C']

$.each(array_of_options, function(i, item) {
    if(i==0) { sel_op = 'selected'; dis_op = 'disabled'; } else { sel_op = ''; dis_op = ''; }
    $('<option ' + sel_op + ' ' + dis_op + '/>').val(item).html(item).appendTo('#tagging');
  })

This will allow the user to see the first option as a disabled heading ('Choose Tagging'), and select all other options.

enter image description here

regular expression to validate datetime format (MM/DD/YYYY)


In this case, to validate Date (DD-MM-YYYY) or (DD/MM/YYYY), with a year between 1900 and 2099,like this with month and Days validation

if (!Regex.Match(txtDob.Text, @"^(0[1-9]|1[0-9]|2[0-9]|3[0,1])([/+-])(0[1-9]|1[0-2])([/+-])(19|20)[0-9]{2}$").Success)                  
{
   MessageBox.Show("InValid Date of Birth");
   txtDob.Focus();
}

Android DialogFragment vs Dialog

You can create generic DialogFragment subclasses like YesNoDialog and OkDialog, and pass in title and message if you use dialogs a lot in your app.

public class YesNoDialog extends DialogFragment
{
    public static final String ARG_TITLE = "YesNoDialog.Title";
    public static final String ARG_MESSAGE = "YesNoDialog.Message";

    public YesNoDialog()
    {

    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        Bundle args = getArguments();
        String title = args.getString(ARG_TITLE);
        String message = args.getString(ARG_MESSAGE);

        return new AlertDialog.Builder(getActivity())
            .setTitle(title)
            .setMessage(message)
            .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {
                    getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_OK, null);
                }
            })
            .setNegativeButton(android.R.string.no, new DialogInterface.OnClickListener()
            {
                @Override
                public void onClick(DialogInterface dialog, int which)
                {
                    getTargetFragment().onActivityResult(getTargetRequestCode(), Activity.RESULT_CANCELED, null);
                }
            })
            .create();
    }
}

Then call it using the following:

    DialogFragment dialog = new YesNoDialog();
    Bundle args = new Bundle();
    args.putString(YesNoDialog.ARG_TITLE, title);
    args.putString(YesNoDialog.ARG_MESSAGE, message);
    dialog.setArguments(args);
    dialog.setTargetFragment(this, YES_NO_CALL);
    dialog.show(getFragmentManager(), "tag");

And handle the result in onActivityResult.

Generate random array of floats between a range

Why not to combine random.uniform with a list comprehension?

>>> def random_floats(low, high, size):
...    return [random.uniform(low, high) for _ in xrange(size)]
... 
>>> random_floats(0.5, 2.8, 5)
[2.366910411506704, 1.878800401620107, 1.0145196974227986, 2.332600336488709, 1.945869474662082]

Static extension methods

specifically I want to overload Boolean.Parse to allow an int argument.

Would an extension for int work?

public static bool ToBoolean(this int source){
    // do it
    // return it
}

Then you can call it like this:

int x = 1;

bool y = x.ToBoolean();

Show history of a file?

You can use git log to display the diffs while searching:

git log -p -- path/to/file

Command to collapse all sections of code?

None of these worked for me. What I found was, in the editor, search the Keyboard Shortcuts file for editor.foldRecursively. That will give you the latest binding. In my case it was CMD + K, CMD + [.

How can I protect my .NET assemblies from decompilation?

If you want to fully protect your app from decompilation, look at Aladdin's Hasp. You can wrap your assemblies in an encrypted shell that can only be accessed by your application. Of course one wonders how they're able to do this but it works. I don't know however if they protect your app from runtime attachment/reflection which is what Crack.NET is able to do.

-- Edit Also be careful of compiling to native code as a solution...there are decompilers for native code as well.

How can I keep Bootstrap popovers alive while being hovered?

I agree that the best way is to use the one given by: David Chase, Cu Ly, and others that the simplest way to do this is to use the container: $(this) property as follows:

$(selectorString).each(function () {
  var $this = $(this);
  $this.popover({
    html: true,
    placement: "top",
    container: $this,
    trigger: "hover",
    title: "Popover",
    content: "Hey, you hovered on element"
  });
});

I want to point out here that the popover in this case will inherit all properties of the current element. So, for example, if you do this for a .btn element(bootstrap), you won't be able to select text inside the popover. Just wanted to record that since I spent quite some time banging my head on this.

Pass a PHP string to a JavaScript variable (and escape newlines)

function escapeJavaScriptText($string)
{
    return str_replace("\n", '\n', str_replace('"', '\"', addcslashes(str_replace("\r", '', (string)$string), "\0..\37'\\")));
}

Where can I find jenkins restful api reference?

Additional Solution: use Restul api wrapper libraries written in Java / python / Ruby - An object oriented wrappers which aim to provide a more conventionally way of controlling a Jenkins server.

For documentation and links: Remote Access API

How to run iPhone emulator WITHOUT starting Xcode?

is it helpful to you see the image enter image description here

Edit

Now with new Xcode if the icon of the Xcode is on dock you can just right click it and form the menu you can select Open Developer Tool and in the sub menu you can select the iOS Simulator to open the simulator without opening the Xcode.!enter image description here

Function Pointers in Java

Relative to most people here I am new to java but since I haven't seen a similar suggestion I have another alternative to suggest. Im not sure if its a good practice or not, or even suggested before and I just didn't get it. I just like it since I think its self descriptive.

 /*Just to merge functions in a common name*/
 public class CustomFunction{ 
 public CustomFunction(){}
 }

 /*Actual functions*/
 public class Function1 extends CustomFunction{
 public Function1(){}
 public void execute(){...something here...}
 }

 public class Function2 extends CustomFunction{
 public Function2(){}
 public void execute(){...something here...}
 }

 .....
 /*in Main class*/
 CustomFunction functionpointer = null;

then depending on the application, assign

 functionpointer = new Function1();
 functionpointer = new Function2();

etc.

and call by

 functionpointer.execute();

Create array of regex matches

(4castle's answer is better than the below if you can assume Java >= 9)

You need to create a matcher and use that to iteratively find matches.

 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 ...

 List<String> allMatches = new ArrayList<String>();
 Matcher m = Pattern.compile("your regular expression here")
     .matcher(yourStringHere);
 while (m.find()) {
   allMatches.add(m.group());
 }

After this, allMatches contains the matches, and you can use allMatches.toArray(new String[0]) to get an array if you really need one.


You can also use MatchResult to write helper functions to loop over matches since Matcher.toMatchResult() returns a snapshot of the current group state.

For example you can write a lazy iterator to let you do

for (MatchResult match : allMatches(pattern, input)) {
  // Use match, and maybe break without doing the work to find all possible matches.
}

by doing something like this:

public static Iterable<MatchResult> allMatches(
      final Pattern p, final CharSequence input) {
  return new Iterable<MatchResult>() {
    public Iterator<MatchResult> iterator() {
      return new Iterator<MatchResult>() {
        // Use a matcher internally.
        final Matcher matcher = p.matcher(input);
        // Keep a match around that supports any interleaving of hasNext/next calls.
        MatchResult pending;

        public boolean hasNext() {
          // Lazily fill pending, and avoid calling find() multiple times if the
          // clients call hasNext() repeatedly before sampling via next().
          if (pending == null && matcher.find()) {
            pending = matcher.toMatchResult();
          }
          return pending != null;
        }

        public MatchResult next() {
          // Fill pending if necessary (as when clients call next() without
          // checking hasNext()), throw if not possible.
          if (!hasNext()) { throw new NoSuchElementException(); }
          // Consume pending so next call to hasNext() does a find().
          MatchResult next = pending;
          pending = null;
          return next;
        }

        /** Required to satisfy the interface, but unsupported. */
        public void remove() { throw new UnsupportedOperationException(); }
      };
    }
  };
}

With this,

for (MatchResult match : allMatches(Pattern.compile("[abc]"), "abracadabra")) {
  System.out.println(match.group() + " at " + match.start());
}

yields

a at 0
b at 1
a at 3
c at 4
a at 5
a at 7
b at 8
a at 10

git status shows fatal: bad object HEAD

Make a copy of your git dir in your local host and run git init there once again. Push the project to a brand new reprository.

Remove a data connection from an Excel 2010 spreadsheet in compatibility mode

I have experienced that a drop-down menu, referring to a control range (for example after copying sheets from one workbook to another), will keep that cell reference after copying the worksheet, and keeps a data connection which is invisible in "Connections". I found this in the "Search" menu in the ribbon, where an arrow can be selected to mark objects. Underneath the arrow is a menu selection to see all the objects listed in a panel. Then you can delete those unwanted objects and the data source/connection is gone...

IntelliJ shortcut to show a popup of methods in a class that can be searched

If you are running on Linux (I tested in Ubuntu 10.04), the shortcut is Ctrl + F12 (same of Windows)

How to add property to a class dynamically?

Only way to dynamically attach a property is to create a new class and its instance with your new property.

class Holder: p = property(lambda x: vs[i], self.fn_readonly)
setattr(self, k, Holder().p)

Pretty Printing JSON with React

Here is a demo react_hooks_debug_print.html in react hooks that is based on Chris's answer. The json data example is from https://json.org/example.html.

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>Hello World</title>
    <script src="https://unpkg.com/react@16/umd/react.development.js"></script>
    <script src="https://unpkg.com/react-dom@16/umd/react-dom.development.js"></script>

    <!-- Don't use this in production: -->
    <script src="https://unpkg.com/[email protected]/babel.min.js"></script>
  </head>
  <body>
    <div id="root"></div>
    <script src="https://raw.githubusercontent.com/cassiozen/React-autobind/master/src/autoBind.js"></script>

    <script type="text/babel">

let styles = {
  root: { backgroundColor: '#1f4662', color: '#fff', fontSize: '12px', },
  header: { backgroundColor: '#193549', padding: '5px 10px', fontFamily: 'monospace', color: '#ffc600', },
  pre: { display: 'block', padding: '10px 30px', margin: '0', overflow: 'scroll', }
}

let data = {
  "glossary": {
    "title": "example glossary",
    "GlossDiv": {
      "title": "S",
      "GlossList": {
        "GlossEntry": {
          "ID": "SGML",
          "SortAs": "SGML",
          "GlossTerm": "Standard Generalized Markup Language",
          "Acronym": "SGML",
          "Abbrev": "ISO 8879:1986",
          "GlossDef": {
            "para": "A meta-markup language, used to create markup languages such as DocBook.",
            "GlossSeeAlso": [
              "GML",
              "XML"
            ]
          },
          "GlossSee": "markup"
        }
      }
    }
  }
}

const DebugPrint = () => {
  const [show, setShow] = React.useState(false);

  return (
    <div key={1} style={styles.root}>
    <div style={styles.header} onClick={ ()=>{setShow(!show)} }>
        <strong>Debug</strong>
    </div>
    { show 
      ? (
      <pre style={styles.pre}>
       {JSON.stringify(data, null, 2) }
      </pre>
      )
      : null
    }
    </div>
  )
}

ReactDOM.render(
  <DebugPrint data={data} />, 
  document.getElementById('root')
);

    </script>

  </body>
</html>

Or in the following way, add the style into header:

    <style>
.root { background-color: #1f4662; color: #fff; fontSize: 12px; }
.header { background-color: #193549; padding: 5px 10px; fontFamily: monospace; color: #ffc600; }
.pre { display: block; padding: 10px 30px; margin: 0; overflow: scroll; }
    </style>

And replace DebugPrint with the follows:

const DebugPrint = () => {
  // https://stackoverflow.com/questions/30765163/pretty-printing-json-with-react
  const [show, setShow] = React.useState(false);

  return (
    <div key={1} className='root'>
    <div className='header' onClick={ ()=>{setShow(!show)} }>
        <strong>Debug</strong>
    </div>
    { show 
      ? (
      <pre className='pre'>
       {JSON.stringify(data, null, 2) }
      </pre>
      )
      : null
    }
    </div>
  )
}

Turn off deprecated errors in PHP 5.3

All the previous answers are correct. Since no one have hinted out how to turn off all errors in PHP, I would like to mention it here:

error_reporting(0); // Turn off warning, deprecated,
                    // notice everything except error

Somebody might find it useful...

How to add a custom CA Root certificate to the CA Store used by pip in Windows?

I think nt86's solution is the most appropriate because it leverages the underlying Windows infrastructure (certificate store). But it doesn't explain how to install python-certifi-win32 to start with since pip is non functional.

The trick is to use --trustedhost to install python-certifi-win32 and then after that, pip will automatically use the windows certificate store to load the certificate used by the proxy.

So in a nutshell, you should do:

pip install python-certifi-win32 -trustedhost pypi.org

and after that you should be good to go

How to copy a java.util.List into another java.util.List

You can use addAll().

eg : wsListCopy.addAll(wsList);

How to find a Java Memory Leak

NetBeans has a built-in profiler.

How can I parse a JSON file with PHP?

More standard answer:

$jsondata = file_get_contents(PATH_TO_JSON_FILE."/jsonfile.json");

$array = json_decode($jsondata,true);

foreach($array as $k=>$val):
    echo '<b>Name: '.$k.'</b></br>';
    $keys = array_keys($val);
    foreach($keys as $key):
        echo '&nbsp;'.ucfirst($key).' = '.$val[$key].'</br>';
    endforeach;
endforeach;

And the output is:

Name: John
 Status = Wait
Name: Jennifer
 Status = Active
Name: James
 Status = Active
 Age = 56
 Count = 10
 Progress = 0.0029857
 Bad = 0

Singleton with Arguments in Java

Singleton is, of course, an "anti-pattern" (assuming a definition of a static with variable state).

If you want a fixed set of immutable value objects, then enums are the way to go. For a large, possibly open-ended set of values, you can use a Repository of some form - usually based on a Map implementation. Of course, when you are dealing with statics be careful with threading (either synchronise sufficiently widely or use a ConcurrentMap either checking that another thread hasn't beaten you or use some form of futures).

Getting the last element of a list

Another method:

some_list.reverse() 
some_list[0]

I get conflicting provisioning settings error when I try to archive to submit an iOS app

I had this same error, but I had already checked "Automatically manage signing".

The solution was to uncheck it, then check it again and reselect the Team. Xcode then fixed whatever was causing the issue on its own.

How do I get the current date and time in PHP?

You can simply use this code to get current date and time

echo date('r', time());

Set the location in iPhone Simulator

As of Xcode 11.6 and Swift 5.3, facility to simulate custom location has been moved from "Debug" to "Features" in iOS Simulator menu.

Android Error - Open Failed ENOENT

With sdk, you can't write to the root of internal storage. This cause your error.

Edit :

Based on your code, to use internal storage with sdk:

final File dir = new File(context.getFilesDir() + "/nfs/guille/groce/users/nicholsk/workspace3/SQLTest");
dir.mkdirs(); //create folders where write files
final File file = new File(dir, "BlockForTest.txt");

How to download file from database/folder using php

I have changed to your code with little modification will works well. Here is the code:

butangDonload.php

<?php
$file = "logo_ldg.png"; //Let say If I put the file name Bang.png
echo "<a href='download1.php?nama=".$file."'>download</a> ";
?>

download.php

<?php
$name= $_GET['nama'];

    header('Content-Description: File Transfer');
    header('Content-Type: application/force-download');
    header("Content-Disposition: attachment; filename=\"" . basename($name) . "\";");
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($name));
    ob_clean();
    flush();
    readfile("your_file_path/".$name); //showing the path to the server where the file is to be download
    exit;
?>

Here you need to show the path from where the file to be download. i.e. will just give the file name but need to give the file path for reading that file. So, it should be replaced by I have tested by using your code and modifying also will works.

The EntityManager is closed

Symfony v4.1.6

Doctrine v2.9.0

Process inserting duplicates in a repository

  1. Get access a registry in your repo


    //begin of repo
    
    /** @var RegistryInterface */
    protected $registry;
    
    public function __construct(RegistryInterface $registry)
    {
        $this->registry = $registry;
        parent::__construct($registry, YourEntity::class);
    }

  1. Wrap risky code into transaction and reset manager in case of exception


    //in repo method
    $em = $this->getEntityManager();
    
    $em->beginTransaction();
    try {
        $em->persist($yourEntityThatCanBeDuplicate);
        $em->flush();
        $em->commit();
    
    } catch (\Throwable $e) {
        //Rollback all nested transactions
        while ($em->getConnection()->getTransactionNestingLevel() > 0) {
            $em->rollback();
        }
        
        //Reset the default em
        if (!$em->isOpen()) {
            $this->registry->resetManager();
        }
    }

Get time difference between two dates in seconds

The Code

var startDate = new Date();
// Do your operations
var endDate   = new Date();
var seconds = (endDate.getTime() - startDate.getTime()) / 1000;

Or even simpler (endDate - startDate) / 1000 as pointed out in the comments unless you're using typescript.


The explanation

You need to call the getTime() method for the Date objects, and then simply subtract them and divide by 1000 (since it's originally in milliseconds). As an extra, when you're calling the getDate() method, you're in fact getting the day of the month as an integer between 1 and 31 (not zero based) as opposed to the epoch time you'd get from calling the getTime() method, representing the number of milliseconds since January 1st 1970, 00:00


Rant

Depending on what your date related operations are, you might want to invest in integrating a library such as date.js or moment.js which make things so much easier for the developer, but that's just a matter of personal preference.

For example in moment.js we would do moment1.diff(moment2, "seconds") which is beautiful.


Useful docs for this answer

How to get english language word database?

You may check *spell en-GB dictionary used by Mozilla, OpenOffice, plenty of other software.

how to run python files in windows command prompt?

First go to the directory where your python script is present by using-

cd path/to/directory

then simply do:

python file_name.py

In WPF, what are the differences between the x:Name and Name attributes?

When you declare a Button element in XAML you are referring to a class defined in windows run time called Button.

Button has many attribute such as background, text, margin, ..... and an attribute called Name.

Now when you declare a Button in XAML is like creating an anonymous object that happened to have an attribute called Name.

In general you can not refer to an anonymous object, but in WPF framework XAML processor enables you to refer to that object by whatever value you have given to Name attribute.

So far so good.

Another way to create an object is create a named object instead of anonymous object. In this case XAML namespace has an attribute for an object called Name (and since it is in XAML name space thus have X:) that you may set so you can identify your object and refer to it.

Conclusion:

Name is an attribute of a specific object, but X:Name is one attribute of that object (there is a class that defines a general object).

Proper way to exit command line program?

Take a look at Job Control on UNIX systems

If you don't have control of your shell, simply hitting ctrl + C should stop the process. If that doesn't work, you can try ctrl + Z and using the jobs and kill -9 %<job #> to kill it. The '-9' is a type of signal. You can man kill to see a list of signals.

Correct syntax to compare values in JSTL <c:if test="${values.type}=='object'">

The comparison needs to be evaluated fully inside EL ${ ... }, not outside.

<c:if test="${values.type eq 'object'}">

As to the docs, those ${} things are not JSTL, but EL (Expression Language) which is a whole subject at its own. JSTL (as every other JSP taglib) is just utilizing it. You can find some more EL examples here.

<c:if test="#{bean.booleanValue}" />
<c:if test="#{bean.intValue gt 10}" />
<c:if test="#{bean.objectValue eq null}" />
<c:if test="#{bean.stringValue ne 'someValue'}" />
<c:if test="#{not empty bean.collectionValue}" />
<c:if test="#{not bean.booleanValue and bean.intValue ne 0}" />
<c:if test="#{bean.enumValue eq 'ONE' or bean.enumValue eq 'TWO'}" />

See also:


By the way, unrelated to the concrete problem, if I guess your intent right, you could also just call Object#getClass() and then Class#getSimpleName() instead of adding a custom getter.

<c:forEach items="${list}" var="value">
    <c:if test="${value['class'].simpleName eq 'Object'}">
        <!-- code here -->
    </c:if>
</c:forEeach>

See also:

Grab a segment of an array in Java without creating a new array on heap

If you're seeking a pointer style aliasing approach, so that you don't even need to allocate space and copy the data then I believe you're out of luck.

System.arraycopy() will copy from your source to destination, and efficiency is claimed for this utility. You do need to allocate the destination array.

Where can I find my Facebook application id and secret key?

Just simply click on your app name and look on your right, you app id should be there

For your app secret, u have to click show.

enter image description here

Hope that helps !

ggplot2 line chart gives "geom_path: Each group consist of only one observation. Do you need to adjust the group aesthetic?"

I found this can also occur if the most of the data plotted is outside of the axis limits. In that case, adjust the axis scales accordingly.

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

For others needing a key binding:

{ "keys": ["ctrl+="], "command": "upper_case" },
{ "keys": ["ctrl+-"], "command": "lower_case" }

How to post ASP.NET MVC Ajax form using JavaScript rather than submit button

Try the following way:

<input type="submit" value="Search" class="search-btn" />
<a href="javascript:;" onclick="$('.search-btn').click();">Go</a>

PHP - add 1 day to date format mm-dd-yyyy

Actually I wanted same alike thing, To get one year backward date, for a given date! :-)

With the hint of above answer from @mohammad mohsenipur I got to the following link, via his given link!

Luckily, there is a method same as date_add method, named date_sub method! :-) I do the following to get done what I wanted!

$date = date_create('2000-01-01');
date_sub($date, date_interval_create_from_date_string('1 years'));
echo date_format($date, 'Y-m-d');

Hopes this answer will help somebody too! :-)

Good luck guys!

Display image as grayscale using matplotlib

try this:

import pylab
from scipy import misc

pylab.imshow(misc.lena(),cmap=pylab.gray())
pylab.show()

How to delete row in gridview using rowdeleting event?

I know this is a late answer but still it would help someone in need of a solution. I recommend to use OnRowCommand for delete operation along with DataKeyNames, keep OnRowDeleting function to avoid exception.

<asp:gridview ID="Gridview1" runat="server" ShowFooter="true" 
     AutoGenerateColumns="false" OnRowDeleting="Gridview1_RowDeleting" OnRowCommand="Gridview1_RowCommand" DataKeyNames="ID">

Include DataKeyNames="ID" in the gridView and specify the same in link button.

<asp:LinkButton ID="lnkdelete" runat="server" CommandName="Delete" CommandArgument='<%#Eval("ID")%>'>Delete</asp:LinkButton>

protected void Gridview1_RowCommand(object sender, GridViewCommandEventArgs e)
{
  if (e.CommandName == "Delete")
    {
      int ID = Convert.ToInt32(e.CommandArgument);
      //now perform the delete operation using ID value
    }
}

protected void Gridview1_RowDeleting(object sender, GridViewDeleteEventArgs e)    
{
//Leave it blank
}

If this is helpful, give me +