Programs & Examples On #Tee

tee is both a Linux syscall and a user program that duplicates the contents of a pipe. The tee syscall is effectively a userland function call that copies memory or remaps pages in a buffer owned by the kernel.

How to duplicate sys.stdout to a log file?

I had this same issue before and found this snippet very useful:

class Tee(object):
    def __init__(self, name, mode):
        self.file = open(name, mode)
        self.stdout = sys.stdout
        sys.stdout = self
    def __del__(self):
        sys.stdout = self.stdout
        self.file.close()
    def write(self, data):
        self.file.write(data)
        self.stdout.write(data)
    def flush(self):
        self.file.flush()

from: http://mail.python.org/pipermail/python-list/2007-May/438106.html

How do I write stderr to a file while using "tee" with a pipe?

The following will work for KornShell(ksh) where the process substitution is not available,

# create a combined(stdin and stdout) collector
exec 3 <> combined.log

# stream stderr instead of stdout to tee, while draining all stdout to the collector
./aaa.sh 2>&1 1>&3 | tee -a stderr.log 1>&3

# cleanup collector
exec 3>&-

The real trick here, is the sequence of the 2>&1 1>&3 which in our case redirects the stderr to stdout and redirects the stdout to descriptor 3. At this point the stderr and stdout are not combined yet.

In effect, the stderr(as stdin) is passed to tee where it logs to stderr.log and also redirects to descriptor 3.

And descriptor 3 is logging it to combined.log all the time. So the combined.log contains both stdout and stderr.

Displaying Windows command prompt output and redirecting it to a file

This works in real time but is also kind a ugly and the performance is slow. Not well tested either:

@echo off
cls
SET MYCOMMAND=dir /B
ECHO File called 'test.bat' > out.txt
for /f "usebackq delims=" %%I in (`%MYCOMMAND%`) do (
  ECHO %%I
  ECHO %%I >> out.txt
) 
pause

Deleting a pointer in C++

There is a rule in C++, for every new there is a delete.

  1. Why won't the first case work? Seems the most straightforward use to use and delete a pointer? The error says the memory wasn't allocated but 'cout' returned an address.

new is never called. So the address that cout prints is the address of the memory location of myVar, or the value assigned to myPointer in this case. By writing:

myPointer = &myVar;

you say:

myPointer = The address of where the data in myVar is stored

  1. On the second example the error is not being triggered but doing a cout of the value of myPointer still returns a memory address?

It returns an address that points to a memory location that has been deleted. Because first you create the pointer and assign its value to myPointer, second you delete it, third you print it. So unless you assign another value to myPointer, the deleted address will remain.

  1. Does #3 really work? Seems to work to me, the pointer is no longer storing an address, is this the proper way to delete a pointer?

NULL equals 0, you delete 0, so you delete nothing. And it's logic that it prints 0 because you did:

myPointer = NULL;

which equals:

myPointer = 0;

When to use static classes in C#

I do tend to use static classes for factories. For example, this is the logging class in one of my projects:

public static class Log
{
   private static readonly ILoggerFactory _loggerFactory =
      IoC.Resolve<ILoggerFactory>();

   public static ILogger For<T>(T instance)
   {
      return For(typeof(T));
   }

   public static ILogger For(Type type)
   {
      return _loggerFactory.GetLoggerFor(type);
   }
}

You might have even noticed that IoC is called with a static accessor. Most of the time for me, if you can call static methods on a class, that's all you can do so I mark the class as static for extra clarity.

Returning null in a method whose signature says return int?

Change your return type to java.lang.Integer . This way you can safely return null

How remove border around image in css?

it's a good idea to use a reset CSS. add this at the top of your CSS file

img, a {border:none, outline: none;}

hope this helps

nginx: send all requests to a single html page

Using just try_files didn't work for me - it caused a rewrite or internal redirection cycle error in my logs.

The Nginx docs had some additional details:

http://nginx.org/en/docs/http/ngx_http_core_module.html#try_files

So I ended up using the following:

root /var/www/mysite;

location / {
    try_files $uri /base.html;
}

location = /base.html {
    expires 30s;
}

how to add <script>alert('test');</script> inside a text box?

Ok to answer this . I simply converted my < and the > to &lt; and &gt;. What was happening previously is i used to set the text <script>alert('1')</script> but before setting the text in the input text browserconverts &lt; and &gt; as < and the >. So hence converting them again to &lt; and &gt;since browser will understand that as only tags and converts them , than executing the script inside <input type="text" />

How do I set up cron to run a file just once at a specific time?

You could put a crontab file in /etc/cron.d which would run a script that would run your command and then delete the crontab file in /etc/cron.d. Of course, that means your script would need to run as root.

maxFileSize and acceptFileTypes in blueimp file upload plugin do not work. Why?

As suggested in an earlier answer, we need to include two additional files - jquery.fileupload-process.js and then jquery.fileupload-validate.js However as I need to perform some additional ajax calls while adding a file, I am subscribing to the fileuploadadd event to perform those calls. Regarding such a usage the author of this plugin suggested the following

Please have a look here: https://github.com/blueimp/jQuery-File-Upload/wiki/Options#wiki-callback-options

Adding additional event listeners via bind (or on method with jQuery 1.7+) method is the preferred option to preserve callback settings by the jQuery File Upload UI version.

Alternatively, you can also simply start the processing in your own callback, like this: https://github.com/blueimp/jQuery-File-Upload/blob/master/js/jquery.fileupload-process.js#L50

Using the combination of the two suggested options, the following code works perfectly for me

$fileInput.fileupload({
    url: 'upload_url',
    type: 'POST',
    dataType: 'json',
    autoUpload: false,
    disableValidation: false,
    maxFileSize: 1024 * 1024,
    messages: {
        maxFileSize: 'File exceeds maximum allowed size of 1MB',
    }
});

$fileInput.on('fileuploadadd', function(evt, data) {
    var $this = $(this);
    var validation = data.process(function () {
        return $this.fileupload('process', data);
    });

    validation.done(function() {
        makeAjaxCall('some_other_url', { fileName: data.files[0].name, fileSizeInBytes: data.files[0].size })
            .done(function(resp) {
                data.formData = data.formData || {};
                data.formData.someData = resp.SomeData;
                data.submit();
        });
    });
    validation.fail(function(data) {
        console.log('Upload error: ' + data.files[0].error);
    });
});

Removing NA observations with dplyr::filter()

From @Ben Bolker:

[T]his has nothing specifically to do with dplyr::filter()

From @Marat Talipov:

[A]ny comparison with NA, including NA==NA, will return NA

From a related answer by @farnsy:

The == operator does not treat NA's as you would expect it to.

Think of NA as meaning "I don't know what's there". The correct answer to 3 > NA is obviously NA because we don't know if the missing value is larger than 3 or not. Well, it's the same for NA == NA. They are both missing values but the true values could be quite different, so the correct answer is "I don't know."

R doesn't know what you are doing in your analysis, so instead of potentially introducing bugs that would later end up being published an embarrassing you, it doesn't allow comparison operators to think NA is a value.

Using Selenium Web Driver to retrieve value of a HTML input

You can do like this :

webelement time=driver.findElement(By.id("input_name")).getAttribute("value");

this will give you the time displaying on the webpage.

SQL Server SELECT into existing table

There are two different ways to implement inserting data from one table to another table.

For Existing Table - INSERT INTO SELECT

This method is used when the table is already created in the database earlier and the data is to be inserted into this table from another table. If columns listed in insert clause and select clause are same, they are not required to list them. It is good practice to always list them for readability and scalability purpose.

----Create testable
CREATE TABLE TestTable (FirstName VARCHAR(100), LastName VARCHAR(100))
----INSERT INTO TestTable using SELECT
INSERT INTO TestTable (FirstName, LastName)
SELECT FirstName, LastName
FROM Person.Contact
WHERE EmailPromotion = 2
----Verify that Data in TestTable
SELECT FirstName, LastName
FROM TestTable
----Clean Up Database
DROP TABLE TestTable

For Non-Existing Table - SELECT INTO

This method is used when the table is not created earlier and needs to be created when data from one table is to be inserted into the newly created table from another table. The new table is created with the same data types as selected columns.

----Create a new table and insert into table using SELECT INSERT
SELECT FirstName, LastName
INTO TestTable
FROM Person.Contact
WHERE EmailPromotion = 2
----Verify that Data in TestTable
SELECT FirstName, LastName
FROM TestTable
----Clean Up Database
DROP TABLE TestTable

Ref 1 2

Put buttons at bottom of screen with LinearLayout?

You can bundle your Button(s) within a RelativeLayout even if your Parent Layout is Linear. Make Sure the outer most parent has android:layout_height attribute set to match_parent. And in that Button tag add 'android:alignParentBottom="True" '

RelativeLayout center vertical

For me, I had to remove

<item name="android:gravity">center_vertical</item>

from RelativeLayout, so children's configuration would work:

<item name="android:layout_centerVertical">true</item>

Could not find or load main class with a Jar File

I had a similar problem which I could solve by granting execute-privilege for all parent folders in which the jar-file is located (on a linux system).

Example:

/folder1/folder2/folder3/executable.jar

all 3 folders (folder1, folder2 and folder3) as well as the executable.jar need execute-privilege for the current user, otherwise the error "Could not find or load main class ..." is returned.

How do I center this form in css?

_x000D_
_x000D_
<!DOCTYPE html>_x000D_
<html>_x000D_
<head>_x000D_
    <title>Private</title>_x000D_
_x000D_
    <!-- local links -->_x000D_
<style>_x000D_
_x000D_
_x000D_
body{_x000D_
    background-color:#6e6969;_x000D_
    text-align:center;_x000D_
}_x000D_
body .form_wrapper{_x000D_
_x000D_
    display:inline-block;_x000D_
    background-color: #fff;_x000D_
    border-radius: 5px;_x000D_
    height: auto;_x000D_
    padding: 15px 18px;_x000D_
    margin: 10% auto;_x000D_
    margin-left: auto;_x000D_
    margin-right: auto;_x000D_
} _x000D_
</style>_x000D_
</head>_x000D_
<body>_x000D_
    <div class = "form_wrapper">_x000D_
        <form method="post" action="function.php">_x000D_
            <h1 class = "formHeading">Admin login form</h1>_x000D_
            <input type = "text" name = "username" id = "username"placeholder = "Enter Username" required = "required">_x000D_
            <input type = "password" name = "password" id  = "password" placeholder = "Enter password" required = "required">_x000D_
            <button type = "submit" >Login</button>_x000D_
            <a href = "#"> froget password!</a>_x000D_
            <a href = "#"><span>?</span>help</a>_x000D_
        </form>_x000D_
_x000D_
    </div>_x000D_
</body>_x000D_
_x000D_
_x000D_
</html>
_x000D_
_x000D_
_x000D_

Android, landscape only orientation?

Just two steps needed:

  1. Apply setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE); after setContentView().

  2. In the AndroidMainfest.xml, put this statement <activity android:name=".YOURCLASSNAME" android:screenOrientation="landscape" />

Hope it helps and happy coding :)

Iterating through populated rows

I'm going to make a couple of assumptions in my answer. I'm assuming your data starts in A1 and there are no empty cells in the first column of each row that has data.

This code will:

  1. Find the last row in column A that has data
  2. Loop through each row
  3. Find the last column in current row with data
  4. Loop through each cell in current row up to last column found.

This is not a fast method but will iterate through each one individually as you suggested is your intention.


Sub iterateThroughAll()
    ScreenUpdating = False
    Dim wks As Worksheet
    Set wks = ActiveSheet

    Dim rowRange As Range
    Dim colRange As Range

    Dim LastCol As Long
    Dim LastRow As Long
    LastRow = wks.Cells(wks.Rows.Count, "A").End(xlUp).Row

    Set rowRange = wks.Range("A1:A" & LastRow)

    'Loop through each row
    For Each rrow In rowRange
        'Find Last column in current row
        LastCol = wks.Cells(rrow, wks.Columns.Count).End(xlToLeft).Column
        Set colRange = wks.Range(wks.Cells(rrow, 1), wks.Cells(rrow, LastCol))

        'Loop through all cells in row up to last col
        For Each cell In colRange
            'Do something to each cell
            Debug.Print (cell.Value)
        Next cell
    Next rrow
    ScreenUpdating = True
End Sub

How enable auto-format code for Intellij IDEA?

You can do this with Save Actions plugin Refer This article on how to configure the plugin.

Save Actions plugin Supports configurable, Eclipse like, save actions, including "optimize imports", "reformat code", "rearrange code", "compile file" and some quick fixes for Java like "add / remove 'this' qualifier", etc. The plugin executes the configured actions when the file is synchronised (or saved) on disk.

  1. Install the plugin
  2. Go to Settings > Other settings > Save actions
  3. Tick Activate save actions on save
  4. Tick Reformat file
  5. Apply > OK

enter image description here

I prefer the hot-keys though, For Mac,

To format the code : Ctrl+Alt(Option)+L

And additionally I do,: Ctrl+Alt(Option)+O , This will remove unused imports and format the import list as well.

Detect whether there is an Internet connection available on Android

Also another important note. You have to set android.permission.ACCESS_NETWORK_STATE in your AndroidManifest.xml for this to work.

_ how could I have found myself the information I needed in the online documentation?

You just have to read the documentation the the classes properly enough and you'll find all answers you are looking for. Check out the documentation on ConnectivityManager. The description tells you what to do.

How to convert NSData to byte array in iPhone?

Already answered, but to generalize to help other readers:

    //Here:   NSData * fileData;
    uint8_t * bytePtr = (uint8_t  * )[fileData bytes];

    // Here, For getting individual bytes from fileData, uint8_t is used.
    // You may choose any other data type per your need, eg. uint16, int32, char, uchar, ... .
    // Make sure, fileData has atleast number of bytes that a single byte chunk would need. eg. for int32, fileData length must be > 4 bytes. Makes sense ?

    // Now, if you want to access whole data (fileData) as an array of uint8_t
    NSInteger totalData = [fileData length] / sizeof(uint8_t);

    for (int i = 0 ; i < totalData; i ++)
    {
        NSLog(@"data byte chunk : %x", bytePtr[i]);
    }

Difference between classification and clustering in data mining?

There are two definitions in data mining "Supervised" and "Unsupervised". When someone tells the computer, algorithm, code, ... that this thing is like an apple and that thing is like an orange, this is supervised learning and using supervised learning (like tags for each sample in a data set) for classifying the data, you'll get classification. But on the other hand if you let the computer find out what is what and differentiate between features of the given data set, in fact learning unsupervised, for classifying the data set this would be called clustering. In this case data that are fed to the algorithm don't have tags and the algorithm should find out different classes.

How to sum a variable by group

The answer provided by rcs works and is simple. However, if you are handling larger datasets and need a performance boost there is a faster alternative:

library(data.table)
data = data.table(Category=c("First","First","First","Second","Third", "Third", "Second"), 
                  Frequency=c(10,15,5,2,14,20,3))
data[, sum(Frequency), by = Category]
#    Category V1
# 1:    First 30
# 2:   Second  5
# 3:    Third 34
system.time(data[, sum(Frequency), by = Category] )
# user    system   elapsed 
# 0.008     0.001     0.009 

Let's compare that to the same thing using data.frame and the above above:

data = data.frame(Category=c("First","First","First","Second","Third", "Third", "Second"),
                  Frequency=c(10,15,5,2,14,20,3))
system.time(aggregate(data$Frequency, by=list(Category=data$Category), FUN=sum))
# user    system   elapsed 
# 0.008     0.000     0.015 

And if you want to keep the column this is the syntax:

data[,list(Frequency=sum(Frequency)),by=Category]
#    Category Frequency
# 1:    First        30
# 2:   Second         5
# 3:    Third        34

The difference will become more noticeable with larger datasets, as the code below demonstrates:

data = data.table(Category=rep(c("First", "Second", "Third"), 100000),
                  Frequency=rnorm(100000))
system.time( data[,sum(Frequency),by=Category] )
# user    system   elapsed 
# 0.055     0.004     0.059 
data = data.frame(Category=rep(c("First", "Second", "Third"), 100000), 
                  Frequency=rnorm(100000))
system.time( aggregate(data$Frequency, by=list(Category=data$Category), FUN=sum) )
# user    system   elapsed 
# 0.287     0.010     0.296 

For multiple aggregations, you can combine lapply and .SD as follows

data[, lapply(.SD, sum), by = Category]
#    Category Frequency
# 1:    First        30
# 2:   Second         5
# 3:    Third        34

Getting current directory in VBScript

'-----Implementation of VB6 App object in VBScript-----
Class clsApplication
    Property Get Path()
          Dim sTmp
          If IsObject(Server) Then
               'Classic ASP
               Path = Server.MapPath("../")
          ElseIf IsObject(WScript) Then 
               'Windows Scripting Host
               Path = Left(WScript.ScriptFullName, InStr(WScript.ScriptFullName, WScript.ScriptName) - 2)
          ElseIf IsObject(window) Then
               'Internet Explorer HTML Application (HTA)
               sTmp = Replace( Replace(Unescape(window.location), "file:///", "") ,"/", "\")
               Path = Left(sTmp, InstrRev( sTmp , "\") - 1)
          End If
    End Property
End Class
Dim App : Set App = New clsApplication 'use as App.Path

Reloading .env variables without restarting server (Laravel 5, shared hosting)

It's possible that your configuration variables are cached. Verify your config/app.php as well as your .env file then try

php artisan cache:clear

on the command line.

How do I get a file name from a full path with PHP?

There are several ways to get the file name and extension. You can use the following one which is easy to use.

$url = 'http://www.nepaltraveldoor.com/images/trekking/nepal/annapurna-region/Annapurna-region-trekking.jpg';
$file = file_get_contents($url); // To get file
$name = basename($url); // To get file name
$ext = pathinfo($url, PATHINFO_EXTENSION); // To get extension
$name2 =pathinfo($url, PATHINFO_FILENAME); // File name without extension

How do I sort arrays using vbscript?

I know this is a pretty old topic but it might come in handy for anyone in the future. the script below does what the fella was trying to achieve purely using vbscript. when sorted terms starting in capital letters will have priority.

for a = UBound(ArrayOfTerms) - 1 To 0 Step -1
    for j= 0 to a
        if ArrayOfTerms(j)>ArrayOfTerms(j+1) then
            temp=ArrayOfTerms(j+1)
            ArrayOfTerms(j+1)=ArrayOfTerms(j)
            ArrayOfTerms(j)=temp
        end if
    next
next 

"No rule to make target 'install'"... But Makefile exists

I also came across the same error. Here is the fix: If you are using Cmake-GUI:

  1. Clean the cache of the loaded libraries in Cmake-GUI File menu.
  2. Configure the libraries.
  3. Generate the Unix file.

If you missed the 3rd step:

*** No rule to make target `install'. Stop.

error will occur.

One-liner if statements, how to convert this if-else-statement

All you'd need in your case is:

return expression;

The reason why is that the expression itself evaluates to a boolean value of true or false, so it's redundant to have an if block (or even a ?: operator).

How do I specify "close existing connections" in sql script

You can disconnect everyone and roll back their transactions with:

alter database [MyDatbase] set single_user with rollback immediate

After that, you can safely drop the database :)

Rails: Why "sudo" command is not recognized?

Sudo is a Unix specific command designed to allow a user to carry out administrative tasks with the appropriate permissions.

Windows does not have (need?) this.

Run the command with the sudo removed from the start.

Array copy values to keys in PHP

$final_array = array_combine($a, $a);

Reference: http://php.net/array-combine

P.S. Be careful with source array containing duplicated keys like the following:

$a = ['one','two','one'];

Note the duplicated one element.

Send email using java

import java.util.Date;
import java.util.Properties;

import javax.mail.Message;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;


public class SendEmail extends Object{

public static void main(String [] args)
{

    try{

        Properties props = new Properties();
        props.put("mail.smtp.host", "smtp.mail.yahoo.com"); // for gmail use smtp.gmail.com
        props.put("mail.smtp.auth", "true");
        props.put("mail.debug", "true"); 
        props.put("mail.smtp.starttls.enable", "true");
        props.put("mail.smtp.port", "465");
        props.put("mail.smtp.socketFactory.port", "465");
        props.put("mail.smtp.socketFactory.class", "javax.net.ssl.SSLSocketFactory");
        props.put("mail.smtp.socketFactory.fallback", "false");

        Session mailSession = Session.getInstance(props, new javax.mail.Authenticator() {

            protected PasswordAuthentication getPasswordAuthentication() {
                return new PasswordAuthentication("[email protected]", "password");
            }
        });

        mailSession.setDebug(true); // Enable the debug mode

        Message msg = new MimeMessage( mailSession );

        //--[ Set the FROM, TO, DATE and SUBJECT fields
        msg.setFrom( new InternetAddress( "[email protected]" ) );
        msg.setRecipients( Message.RecipientType.TO,InternetAddress.parse("[email protected]") );
        msg.setSentDate( new Date());
        msg.setSubject( "Hello World!" );

        //--[ Create the body of the mail
        msg.setText( "Hello from my first e-mail sent with JavaMail" );

        //--[ Ask the Transport class to send our mail message
        Transport.send( msg );

    }catch(Exception E){
        System.out.println( "Oops something has gone pearshaped!");
        System.out.println( E );
    }
}
}

Required jar files

Click here - How to add External Jars

Should I use window.navigate or document.location in JavaScript?

You can move your page using

window.location.href =Url;

PHP script to loop through all of the files in a directory?

Use the scandir() function:

<?php
    $directory = '/path/to/files';

    if (!is_dir($directory)) {
        exit('Invalid diretory path');
    }

    $files = array();
    foreach (scandir($directory) as $file) {
        if ($file !== '.' && $file !== '..') {
            $files[] = $file;
        }
    }

    var_dump($files);
?>

How do I cancel an HTTP fetch() request?

TL/DR:

fetch now supports a signal parameter as of 20 September 2017, but not all browsers seem support this at the moment.

2020 UPDATE: Most major browsers (Edge, Firefox, Chrome, Safari, Opera, and a few others) support the feature, which has become part of the DOM living standard. (as of 5 March 2020)

This is a change we will be seeing very soon though, and so you should be able to cancel a request by using an AbortControllers AbortSignal.

Long Version

How to:

The way it works is this:

Step 1: You create an AbortController (For now I just used this)

const controller = new AbortController()

Step 2: You get the AbortControllers signal like this:

const signal = controller.signal

Step 3: You pass the signal to fetch like so:

fetch(urlToFetch, {
    method: 'get',
    signal: signal, // <------ This is our AbortSignal
})

Step 4: Just abort whenever you need to:

controller.abort();

Here's an example of how it would work (works on Firefox 57+):

_x000D_
_x000D_
<script>_x000D_
    // Create an instance._x000D_
    const controller = new AbortController()_x000D_
    const signal = controller.signal_x000D_
_x000D_
    /*_x000D_
    // Register a listenr._x000D_
    signal.addEventListener("abort", () => {_x000D_
        console.log("aborted!")_x000D_
    })_x000D_
    */_x000D_
_x000D_
_x000D_
    function beginFetching() {_x000D_
        console.log('Now fetching');_x000D_
        var urlToFetch = "https://httpbin.org/delay/3";_x000D_
_x000D_
        fetch(urlToFetch, {_x000D_
                method: 'get',_x000D_
                signal: signal,_x000D_
            })_x000D_
            .then(function(response) {_x000D_
                console.log(`Fetch complete. (Not aborted)`);_x000D_
            }).catch(function(err) {_x000D_
                console.error(` Err: ${err}`);_x000D_
            });_x000D_
    }_x000D_
_x000D_
_x000D_
    function abortFetching() {_x000D_
        console.log('Now aborting');_x000D_
        // Abort._x000D_
        controller.abort()_x000D_
    }_x000D_
_x000D_
</script>_x000D_
_x000D_
_x000D_
_x000D_
<h1>Example of fetch abort</h1>_x000D_
<hr>_x000D_
<button onclick="beginFetching();">_x000D_
    Begin_x000D_
</button>_x000D_
<button onclick="abortFetching();">_x000D_
    Abort_x000D_
</button>
_x000D_
_x000D_
_x000D_

Sources:

How to add AUTO_INCREMENT to an existing column?

ALTER TABLE Table name ADD column datatype AUTO_INCREMENT,ADD primary key(column);

Getting "error": "unsupported_grant_type" when trying to get a JWT by calling an OWIN OAuth secured Web Api via Postman

  1. Note the URL: localhost:55828/token (not localhost:55828/API/token)
  2. Note the request data. Its not in json format, its just plain data without double quotes. [email protected]&password=Test123$&grant_type=password
  3. Note the content type. Content-Type: 'application/x-www-form-urlencoded' (not Content-Type: 'application/json')
  4. When you use JavaScript to make post request, you may use following:

    $http.post("localhost:55828/token", 
      "userName=" + encodeURIComponent(email) +
        "&password=" + encodeURIComponent(password) +
        "&grant_type=password",
      {headers: { 'Content-Type': 'application/x-www-form-urlencoded' }}
    ).success(function (data) {//...
    

See screenshots below from Postman:

Postman Request

Postman Request Header

How to use doxygen to create UML class diagrams from C++ source

Enterprise Architect will build a UML diagram from imported source code.

How to get length of a list of lists in python

This saves the data in a list of lists.

text = open("filetest.txt", "r")
data = [ ]
for line in text:
    data.append( line.strip().split() )

print "number of lines ", len(data)
print "number of columns ", len(data[0])

print "element in first row column two ", data[0][1]

What's the difference between "super()" and "super(props)" in React when using es6 classes?

When you pass props to super, the props get assigned to this. Take a look at the following scenario:

constructor(props) {
    super();
    console.log(this.props) //undefined
}

How ever when you do :

constructor(props) {
    super(props);
    console.log(this.props) //props will get logged.
}

How to dynamically remove items from ListView on a button click?

      private List<DataValue> datavalue=new ArrayList<Datavalue>;

     @Override
    public View getView(int position, View view, ViewGroup viewGroup) {

            view.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {

                datavalue.remove(position);
                notifyDataSetChanged();
            }
        });
    }
    }

keytool error bash: keytool: command not found

find your jre location ::sudo find / -name jre And then :: sudo update-alternatives --install /usr/bin/keytool keytool /opt/jdk/<jdk.verson>/jre/bin/keytool 100

Delete all data rows from an Excel table (apart from the first)

I suggest first clearcontents, then resize Table:

Sub DeleteTableRows(ByRef Table As ListObject)

     Dim R               As Range

On Error Resume Next

    Table.DataBodyRange.ClearContents
    Set R = Table.Range.Rows(1).Resize(2)
    Table.Resize R

On Error GoTo 0

End Sub

How to read file with space separated values in pandas

you can use regex as the delimiter:

pd.read_csv("whitespace.csv", header=None, delimiter=r"\s+")

How do you completely remove the button border in wpf?

You may already know that putting your Button inside of a ToolBar gives you this behavior, but if you want something that will work across ALL current themes with any sort of predictability, you'll need to create a new ControlTemplate.

Prashant's solution does not work with a Button not in a toolbar when the Button has focus. It also doesn't work 100% with the default theme in XP -- you can still see faint gray borders when your container Background is white.

Retrieve last 100 lines logs

len=`cat filename | wc -l`
len=$(( $len + 1 ))
l=$(( $len - 99 ))
sed -n "${l},${len}p" filename

first line takes the length (Total lines) of file then +1 in the total lines after that we have to fatch 100 records so, -99 from total length then just put the variables in the sed command to fetch the last 100 lines from file

I hope this will help you.

Keeping session alive with Curl and PHP

You have correctly used "CURLOPT_COOKIEJAR" (writing) but you also need to set "CURLOPT_COOKIEFILE" (reading)

curl_setopt ($ch, CURLOPT_COOKIEJAR, COOKIE_FILE); 
curl_setopt ($ch, CURLOPT_COOKIEFILE, COOKIE_FILE); 

Is there a Google Voice API?

I looked for a C/C++ API for Google Voice for quite a while and never found anything close (the closest was a C# API). Since I really needed it, I decided to just write one myself:

http://github.com/mastermind202/GoogleVoice

I hope others find it useful. Feedback and suggestions welcome.

How can I find the OWNER of an object in Oracle?

To find the name of the current user within an Oracle session, use the USER function.

Note that the owner of the constraint, the owner of the table containing the foreign key, and the owner of the referenced table may all be different. It sounds like it’s the table owner you’re interested in, in which case this should be close to what you want:

select Constraint_Name
from All_Constraints
where Table_Name = 'WHICHEVER_TABLE'
  and Constraint_Type = 'R' and Owner = User;

What is inf and nan?

You say:

when i do nan - inf i dont get -inf i get nan

This is because any operation containing NaN as an operand would return NaN.

A comparison with NaN would return an unordered result.

>>> float('Inf') == float('Inf')
True
>>> float('NaN') == float('NaN')
False

sql ORDER BY multiple values in specific order?

you can use position(text in text) in order by for ordering the sequence

Call a VBA Function into a Sub Procedure

Here are some of the different ways you can call things in Microsoft Access:

To call a form sub or function from a module

The sub in the form you are calling MUST be public, as in:

Public Sub DoSomething()
  MsgBox "Foo"
End Sub

Call the sub like this:

Call Forms("form1").DoSomething

The form must be open before you make the call.

To call an event procedure, you should call a public procedure within the form, and call the event procedure within this public procedure.

To call a subroutine in a module from a form

Public Sub DoSomethingElse()
  MsgBox "Bar"
End Sub

...just call it directly from your event procedure:

Call DoSomethingElse

To call a subroutine from a form without using an event procedure

If you want, you can actually bind the function to the form control's event without having to create an event procedure under the control. To do this, you first need a public function in the module instead of a sub, like this:

Public Function DoSomethingElse()
  MsgBox "Bar"
End Function

Then, if you have a button on the form, instead of putting [Event Procedure] in the OnClick event of the property window, put this:

=DoSomethingElse()

When you click the button, it will call the public function in the module.

To call a function instead of a procedure

If calling a sub looks like this:

Call MySub(MyParameter)

Then calling a function looks like this:

Result=MyFunction(MyFarameter)

where Result is a variable of type returned by the function.

NOTE: You don't always need the Call keyword. Most of the time, you can just call the sub like this:

MySub(MyParameter)

What are the rules for calling the superclass constructor?

Base class constructors are automatically called for you if they have no argument. If you want to call a superclass constructor with an argument, you must use the subclass's constructor initialization list. Unlike Java, C++ supports multiple inheritance (for better or worse), so the base class must be referred to by name, rather than "super()".

class SuperClass
{
    public:

        SuperClass(int foo)
        {
            // do something with foo
        }
};

class SubClass : public SuperClass
{
    public:

        SubClass(int foo, int bar)
        : SuperClass(foo)    // Call the superclass constructor in the subclass' initialization list.
        {
            // do something with bar
        }
};

More info on the constructor's initialization list here and here.

How to display a list of images in a ListView in Android?

File name should match the layout id which in this example is : items_list_item.xml in the layout folder of your application

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    >  

<ImageView android:id="@+id/R.id.list_item_image"
  android:layout_width="100dip"
  android:layout_height="wrap_content" />  
</LinearLayout>

How to change date format in JavaScript

Using the Datejs library, this can be as easy as:

Date.parse("05/05/2010").toString("MMMM yyyy");
//          parse date             convert to
//                                 string with
//                                 custom format

How to read a large file line by line?

If you're opening a big file, you probably want to use Generators alongside fgets() to avoid loading the whole file into memory:

/**
 * @return Generator
 */
$fileData = function() {
    $file = fopen(__DIR__ . '/file.txt', 'r');

    if (!$file)
        die('file does not exist or cannot be opened');

    while (($line = fgets($file)) !== false) {
        yield $line;
    }

    fclose($file);
};

Use it like this:

foreach ($fileData() as $line) {
    // $line contains current line
}

This way you can process individual file lines inside the foreach().

Note: Generators require >= PHP 5.5

How to save a PNG image server-side, from a base64 data string

You need to extract the base64 image data from that string, decode it and then you can save it to disk, you don't need GD since it already is a png.

$data = 'data:image/png;base64,AAAFBfj42Pj4';

list($type, $data) = explode(';', $data);
list(, $data)      = explode(',', $data);
$data = base64_decode($data);

file_put_contents('/tmp/image.png', $data);

And as a one-liner:

$data = base64_decode(preg_replace('#^data:image/\w+;base64,#i', '', $data));

An efficient method for extracting, decoding, and checking for errors is:

if (preg_match('/^data:image\/(\w+);base64,/', $data, $type)) {
    $data = substr($data, strpos($data, ',') + 1);
    $type = strtolower($type[1]); // jpg, png, gif

    if (!in_array($type, [ 'jpg', 'jpeg', 'gif', 'png' ])) {
        throw new \Exception('invalid image type');
    }
    $data = str_replace( ' ', '+', $data );
    $data = base64_decode($data);

    if ($data === false) {
        throw new \Exception('base64_decode failed');
    }
} else {
    throw new \Exception('did not match data URI with image data');
}

file_put_contents("img.{$type}", $data);

JavaScript dictionary with names

You may be trying to use a JSON object:

var myMappings = { "name": "10%", "phone": "10%", "address": "50%", etc.. }

To access:

myMappings.name;
myMappings.phone;
etc..

Auto expand a textarea using jQuery

Simple Solution:

HTML:

<textarea class='expand'></textarea>

JS:

$('textarea.expand').on('input', function() {
  $(this).scrollTop($(this).height());
});
$('textarea.expand').scroll(function() {
  var h = $(this).scrollTop();
  if (h > 0)
    $(this).height($(this).height() + h);
});

https://fiddle.jshell.net/7wsnwbzg/

How do I remove files saying "old mode 100755 new mode 100644" from unstaged changes in Git?

It seems you have changed some permissions of the directory. I did the following steps to restore it.

$  git diff > backup-diff.txt                ### in case you have some other code changes 

$  git checkout .

Difference in boto3 between resource, client, and session?

I'll try and explain it as simple as possible. So there is no guarantee of the accuracy of the actual terms.

Session is where to initiate the connectivity to AWS services. E.g. following is default session that uses the default credential profile(e.g. ~/.aws/credentials, or assume your EC2 using IAM instance profile )

sqs = boto3.client('sqs')
s3 = boto3.resource('s3')

Because default session is limit to the profile or instance profile used, sometimes you need to use the custom session to override the default session configuration (e.g. region_name, endpoint_url, etc. ) e.g.

# custom resource session must use boto3.Session to do the override
my_west_session = boto3.Session(region_name = 'us-west-2')
my_east_session = boto3.Session(region_name = 'us-east-1')
backup_s3 = my_west_session.resource('s3')
video_s3 = my_east_session.resource('s3')

# you have two choices of create custom client session. 
backup_s3c = my_west_session.client('s3')
video_s3c = boto3.client("s3", region_name = 'us-east-1')

Resource : This is the high-level service class recommended to be used. This allows you to tied particular AWS resources and passes it along, so you just use this abstraction than worry which target services are pointed to. As you notice from the session part, if you have a custom session, you just pass this abstract object than worrying about all custom regions,etc to pass along. Following is a complicated example E.g.

import boto3 
my_west_session = boto3.Session(region_name = 'us-west-2')
my_east_session = boto3.Session(region_name = 'us-east-1')
backup_s3 = my_west_session.resource("s3")
video_s3 = my_east_session.resource("s3")
backup_bucket = backup_s3.Bucket('backupbucket') 
video_bucket = video_s3.Bucket('videobucket')

# just pass the instantiated bucket object
def list_bucket_contents(bucket):
   for object in bucket.objects.all():
      print(object.key)

list_bucket_contents(backup_bucket)
list_bucket_contents(video_bucket)

Client is a low level class object. For each client call, you need to explicitly specify the targeting resources, the designated service target name must be pass long. You will lose the abstraction ability.

For example, if you only deal with the default session, this looks similar to boto3.resource.

import boto3 
s3 = boto3.client('s3')

def list_bucket_contents(bucket_name):
   for object in s3.list_objects_v2(Bucket=bucket_name) :
      print(object.key)

list_bucket_contents('Mybucket') 

However, if you want to list objects from a bucket in different regions, you need to specify the explicit bucket parameter required for the client.

import boto3 
backup_s3 = my_west_session.client('s3',region_name = 'us-west-2')
video_s3 = my_east_session.client('s3',region_name = 'us-east-1')

# you must pass boto3.Session.client and the bucket name 
def list_bucket_contents(s3session, bucket_name):
   response = s3session.list_objects_v2(Bucket=bucket_name)
   if 'Contents' in response:
     for obj in response['Contents']:
        print(obj['key'])

list_bucket_contents(backup_s3, 'backupbucket')
list_bucket_contents(video_s3 , 'videobucket') 

How do I UPDATE a row in a table or INSERT it if it doesn't exist?

I don't know that you are going to find a platform-neutral solution.

This is commonly called an "UPSERT".

See some related discussions:

How do you receive a url parameter with a spring controller mapping

You should be using @RequestParam instead of @ModelAttribute, e.g.

@RequestMapping("/{someID}")
public @ResponseBody int getAttr(@PathVariable(value="someID") String id, 
                                 @RequestParam String someAttr) {
}

You can even omit @RequestParam altogether if you choose, and Spring will assume that's what it is:

@RequestMapping("/{someID}")
public @ResponseBody int getAttr(@PathVariable(value="someID") String id, 
                                 String someAttr) {
}

WebSocket connection failed: Error during WebSocket handshake: Unexpected response code: 400

Problem solved! I just figured out how to solve the issue, but I would still like to know if this is normal behavior or not.

It seems that even though the Websocket connection establishes correctly (indicated by the 101 Switching Protocols request), it still defaults to long-polling. The fix was as simple as adding this option to the Socket.io connection function:

{transports: ['websocket']}

So the code finally looks like this:

const app = express();
const server = http.createServer(app);
var io = require('socket.io')(server);

io.on('connection', function(socket) {
  console.log('connected socket!');

  socket.on('greet', function(data) {
    console.log(data);
    socket.emit('respond', { hello: 'Hey, Mr.Client!' });
  });
  socket.on('disconnect', function() {
    console.log('Socket disconnected');
  });
});

and on the client:

var socket = io('ws://localhost:3000', {transports: ['websocket']});
socket.on('connect', function () {
  console.log('connected!');
  socket.emit('greet', { message: 'Hello Mr.Server!' });
});

socket.on('respond', function (data) {
  console.log(data);
});

And the messages now appear as frames:

working websockets

This Github issue pointed me in the right direction. Thanks to everyone who helped out!

ImportError: No module named enum

I ran into this issue with Python 3.6 and Python 3.7. The top answer (running pip install --upgrade pip enum34) did not solve the problem.


I don't know why, but the reason why this error happen is because enum.py was missing from .venv/myvenv/lib/python3.7/.

But the file was in /usr/lib/python3.7/.

Following this answer, I just created the symbolic link by myself :

ln -s /usr/lib/python3.7/enum.py .venv/myvenv/lib/python3.7/enum.py

Charts for Android

SciChart for Android is a relative newcomer, but brings extremely fast high performance real-time charting to the Android platform.

SciChart is a commercial control but available under royalty free distribution / per developer licensing. There is also free licensing available for educational use with some conditions.

Some useful links can be found below:

enter image description here

Disclosure: I am the tech lead on the SciChart project!

Comparing two dataframes and getting the differences

Hope this would be useful to you. ^o^

df1 = pd.DataFrame({'date': ['0207', '0207'], 'col1': [1, 2]})
df2 = pd.DataFrame({'date': ['0207', '0207', '0208', '0208'], 'col1': [1, 2, 3, 4]})
print(f"df1(Before):\n{df1}\ndf2:\n{df2}")
"""
df1(Before):
   date  col1
0  0207     1
1  0207     2

df2:
   date  col1
0  0207     1
1  0207     2
2  0208     3
3  0208     4
"""

old_set = set(df1.index.values)
new_set = set(df2.index.values)
new_data_index = new_set - old_set
new_data_list = []
for idx in new_data_index:
    new_data_list.append(df2.loc[idx])

if len(new_data_list) > 0:
    df1 = df1.append(new_data_list)
print(f"df1(After):\n{df1}")
"""
df1(After):
   date  col1
0  0207     1
1  0207     2
2  0208     3
3  0208     4
"""

Call PHP function from jQuery?

Thanks all. I took bits of each of your solutions and made my own.

The final working solution is:

<script type="text/javascript">
    $(document).ready(function(){
        $.ajax({
            url: '<?php bloginfo('template_url'); ?>/functions/twitter.php',
            data: "tweets=<?php echo $ct_tweets; ?>&account=<?php echo $ct_twitter; ?>",
            success: function(data) {
                $('#twitter-loader').remove();
                $('#twitter-container').html(data);
            }
        });
   });
</script>

Convert JSON String to Pretty Print JSON output using Jackson

For Jackson 1.9, We can use the following code for pretty print.

ObjectMapper objectMapper = new ObjectMapper();
objectMapper.enable(SerializationConfig.Feature.INDENT_OUTPUT);

IndexError: too many indices for array

I think the problem is given in the error message, although it is not very easy to spot:

IndexError: too many indices for array
xs  = data[:, col["l1"     ]]

'Too many indices' means you've given too many index values. You've given 2 values as you're expecting data to be a 2D array. Numpy is complaining because data is not 2D (it's either 1D or None).

This is a bit of a guess - I wonder if one of the filenames you pass to loadfile() points to an empty file, or a badly formatted one? If so, you might get an array returned that is either 1D, or even empty (np.array(None) does not throw an Error, so you would never know...). If you want to guard against this failure, you can insert some error checking into your loadfile function.

I highly recommend in your for loop inserting:

print(data)

This will work in Python 2.x or 3.x and might reveal the source of the issue. You might well find it is only one value of your outputs_l1 list (i.e. one file) that is giving the issue.

Android Studio: Module won't show up in "Edit Configuration"

Sometimes the errors exists in Android-manifest because of that there is cross like image over run/debug configuration hence try to look over if Android-manifest has any errors in just case.

What's the best three-way merge tool?

KDiff3 open source, cross platform

Same interface for Linux and Windows, very smart algorithm for solving conflicts, regular expressions for automatically solving conflicts, integrate with ClearCase, SVN, Git, MS Visual Studio, editable merged file, compare directories

Its keyboard-navigation is great: ctrl-arrows to navigate the diffs, ctrl-1, 2, 3 to do the merging.

Also, see https://stackoverflow.com/a/2434482/42473

enter image description here

SMTP Connect() failed. Message was not sent.Mailer error: SMTP Connect() failed

the solution is configure the gmail preferences, access to no secure application

How do I add the Java API documentation to Eclipse?

To use offline Java API Documentation in Eclipse, you need to download it first. The link for Java docs are (last updated on 2013-10-21):

Java 6
Page: http://www.oracle.com/technetwork/java/javase/downloads/jdk-6u25-doc-download-355137.html
Direct: http://download.oracle.com/otn-pub/java/jdk/6u30-b12/jdk-6u30-apidocs.zip

Java 7
Page: http://www.oracle.com/technetwork/java/javase/documentation/java-se-7-doc-download-435117.html

Java 8
Page: http://www.oracle.com/technetwork/java/javase/documentation/jdk8-doc-downloads-2133158.html

Java 9
Page:http://www.oracle.com/technetwork/java/javase/documentation/jdk9-doc-downloads-3850606.html

  1. Extract the zip file in your local directory.
  2. From eclipse Window --> Preferences --> Java --> "Installed JREs" select available JRE (jre6: C:\Program Files (x86)\Java\jre6 for instance) and click Edit.
  3. Select all the "JRE System libraries" using Control+A.
  4. Click "Javadoc Location"
  5. Change "Javadoc location path:" from "http://download.oracle.com/javase/6/docs/api/" to "file:/E:/Java/docs/api/".

It must work as it works for me. I don't need Internet connection to view Java API Documentation in Eclipse anymore.

Delimiters in MySQL

Delimiters other than the default ; are typically used when defining functions, stored procedures, and triggers wherein you must define multiple statements. You define a different delimiter like $$ which is used to define the end of the entire procedure, but inside it, individual statements are each terminated by ;. That way, when the code is run in the mysql client, the client can tell where the entire procedure ends and execute it as a unit rather than executing the individual statements inside.

Note that the DELIMITER keyword is a function of the command line mysql client (and some other clients) only and not a regular MySQL language feature. It won't work if you tried to pass it through a programming language API to MySQL. Some other clients like PHPMyAdmin have other methods to specify a non-default delimiter.

Example:

DELIMITER $$
/* This is a complete statement, not part of the procedure, so use the custom delimiter $$ */
DROP PROCEDURE my_procedure$$

/* Now start the procedure code */
CREATE PROCEDURE my_procedure ()
BEGIN    
  /* Inside the procedure, individual statements terminate with ; */
  CREATE TABLE tablea (
     col1 INT,
     col2 INT
  );

  INSERT INTO tablea
    SELECT * FROM table1;

  CREATE TABLE tableb (
     col1 INT,
     col2 INT
  );
  INSERT INTO tableb
    SELECT * FROM table2;
  
/* whole procedure ends with the custom delimiter */
END$$

/* Finally, reset the delimiter to the default ; */
DELIMITER ;

Attempting to use DELIMITER with a client that doesn't support it will cause it to be sent to the server, which will report a syntax error. For example, using PHP and MySQLi:

$mysqli = new mysqli('localhost', 'user', 'pass', 'test');
$result = $mysqli->query('DELIMITER $$');
echo $mysqli->error;

Errors with:

You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'DELIMITER $$' at line 1

Adding elements to a collection during iteration

Use ListIterator as follows:

List<String> l = new ArrayList<>();
l.add("Foo");
ListIterator<String> iter = l.listIterator(l.size());
while(iter.hasPrevious()){
    String prev=iter.previous();
    if(true /*You condition here*/){
        iter.add("Bah");
        iter.add("Etc");
    }
}

The key is to iterate in reverse order - then the added elements appear on the next iteration.

Polymorphism vs Overriding vs Overloading

Polymorphism means more than one form, same object performing different operations according to the requirement.

Polymorphism can be achieved by using two ways, those are

  1. Method overriding
  2. Method overloading

Method overloading means writing two or more methods in the same class by using same method name, but the passing parameters is different.

Method overriding means we use the method names in the different classes,that means parent class method is used in the child class.

In Java to achieve polymorphism a super class reference variable can hold the sub class object.

To achieve the polymorphism every developer must use the same method names in the project.

Convert a row of a data frame to vector

Columns of data frames are already vectors, you just have to pull them out. Note that you place the column you want after the comma, not before it:

> newV <- df[,1]
> newV
[1] 1 2 4 2

If you actually want a row, then do what Ben said and please use words correctly in the future.

Vue.js unknown custom element

This solved it for me: I supplied a third argument being an object.

in app.js (working with laravel and webpack):

Vue.component('news-item', require('./components/NewsItem.vue'), {
    name: 'news-item'
});

Android button font size

Button butt= new Button(_context);
butt.setTextAppearance(_context, R.style.ButtonFontStyle);

and in res/values/style.xml

<resources>   
    <style name="ButtonFontStyle">
            <item name="android:textSize">12sp</item>
    </style>
</resources>

Frontend tool to manage H2 database

I would like to suggest DBEAVER .it is based on eclipse and supports better data handling

How to delete from multiple tables in MySQL?

To anyone reading this in 2017, this is how I've done something similar.

DELETE pets, pets_activities FROM pets inner join pets_activities
on pets_activities.id = pets.id WHERE pets.`order` > :order AND 
pets.`pet_id` = :pet_id

Generally, to delete rows from multiple tables, the syntax I follow is given below. The solution is based on an assumption that there is some relation between the two tables.

DELETE table1, table2 FROM table1 inner join table2 on table2.id = table1.id
WHERE [conditions]

Bash: If/Else statement in one line

You can make full use of the && and || operators like this:

ps aux | grep some_proces[s] > /tmp/test.txt && echo 1 || echo 0

For excluding grep itself, you could also do something like:

ps aux | grep some_proces | grep -vw grep > /tmp/test.txt && echo 1 || echo 0

Data truncation: Data too long for column 'logo' at row 1

Use data type LONGBLOB instead of BLOB in your database table.

Why Visual Studio 2015 can't run exe file (ucrtbased.dll)?

I would like to suggest additional solution to fix this issue. So, I recommend to reinstall/install the latest Windows SDK. In my case it has helped me to fix the issue when using Qt with MSVC compiler to debug a program.

Copy every nth line from one sheet to another

If your original data is in column form with multiple columns and the first entry of your original data in C42, and you want your new (down-sampled) data to be in column form as well, but only every seventh row, then you will also need to subtract out the row number of the first entry, like so:

=OFFSET(C$42,(ROW(C42)-ROW(C$42))*7,0)

Python: AttributeError: '_io.TextIOWrapper' object has no attribute 'split'

You're not reading the file content:

my_file_contents = f.read()

See the docs for further infos

You could, without calling read() or readlines() loop over your file object:

f = open('goodlines.txt')
for line in f:
    print(line)

If you want a list out of it (without \n as you asked)

my_list = [line.rstrip('\n') for line in f]

How change default SVN username and password to commit changes?

since your local username on your laptop frequently does not match the server's username, you can set this in the ~/.subversion/servers file

Add the server to the [groups] section with a name, then add a section with that name and provide a username.

for example, for a login like [email protected] this is what your config would look like:

[groups]
exampleserver = svn.example.com

[exampleserver]
username = me

Maven version with a property

If you have a parent project you can set the version in the parent pom and in the children you can reference sibling libs with the ${project.version} or ${version} properties.

If you want to avoid to repeat the version of the parent in each children: you can do this:

<modelVersion>4.0.0</modelVersion>
<groupId>company</groupId>
<artifactId>build.parent</artifactId>
<version>${my.version}</version>
<packaging>pom</packaging>

<properties>
<my.version>1.1.2-SNAPSHOT</my.version>
</properties>

And then in your children pom you have to do:

    <parent>
      <artifactId>build.parent</artifactId>
      <groupId>company</groupId>
      <relativePath>../build.parent/pom.xml</relativePath>
      <version>${my.version}</version>
    </parent>

    <modelVersion>4.0.0</modelVersion>
    <groupId>company</groupId>
    <artifactId>artifact</artifactId>
    <packaging>eclipse-plugin</packaging>

    <dependencies>
        <dependency> 
           <groupId>company</groupId>
           <artifactId>otherartifact</artifactId>   
           <version>${my.version}</version>
or
           <version>${project.version}</version>
        </dependency>
    </dependencies>

hth

How to connect android emulator to the internet

I also experienced the same problem. The simplest solution I found out is:

  • Go to your Android\Sdk\emulator folder and open command prompt.
  • Type emulator -list-avds to see available emulator names.
  • Type emulator -avd name-of-your-device -netdelay none -netspeed full -dns-server 8.8.8.8 command and press enter.

Read line by line in bash script

If you want to use each of the lines of the file as command-line params for your application you can use the xargs command.

xargs -a <params_file> <command>

A params file with:

a
b
c
d

and the file tr.py:

import sys
print sys.argv

The execution of

xargs -a params ./tr.py

gives the result:

['./tr.py', 'a', 'b', 'c', 'd']

Check if PHP-page is accessed from an iOS device

function user_agent(){
    $iPod = strpos($_SERVER['HTTP_USER_AGENT'],"iPod");
    $iPhone = strpos($_SERVER['HTTP_USER_AGENT'],"iPhone");
    $iPad = strpos($_SERVER['HTTP_USER_AGENT'],"iPad");
    $android = strpos($_SERVER['HTTP_USER_AGENT'],"Android");
    file_put_contents('./public/upload/install_log/agent',$_SERVER['HTTP_USER_AGENT']);
    if($iPad||$iPhone||$iPod){
        return 'ios';
    }else if($android){
        return 'android';
    }else{
        return 'pc';
    }
}

Remove duplicate values from JS array

The simplest way to remove a duplicate is to do a for loop and compare the elements that are not the same and push them into the new array

 var array = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"];

 var removeDublicate = function(arr){
 var result = []
 var sort_arr = arr.sort() //=> optional
 for (var i = 0; i < arr.length; i++) {
        if(arr[ i + 1] !== arr[i] ){
            result.push(arr[i])
        }
 };
  return result
}  
console.log(removeDublicate(array))
==>  ["Adam", "Carl", "Jenny", "Matt", "Mike", "Nancy"]

Best Practice: Initialize JUnit class fields in setUp() or at declaration?

In addition to Alex B's answer.

It is even required to use the setUp method to instantiate resources in a certain state. Doing this in the constructor is not only a matter of timings, but because of the way JUnit runs the tests, each test state would be erased after running one.

JUnit first creates instances of the testClass for each test method and starts running the tests after each instance is created. Before running the test method, its setup method is ran, in which some state can be prepared.

If the database state would be created in the constructor, all instances would instantiate the db state right after each other, before running each tests. As of the second test, tests would run with a dirty state.

JUnits lifecycle:

  1. Create a different testclass instance for each test method
  2. Repeat for each testclass instance: call setup + call the testmethod

With some loggings in a test with two test methods you get: (number is the hashcode)

  • Creating new instance: 5718203
  • Creating new instance: 5947506
  • Setup: 5718203
  • TestOne: 5718203
  • Setup: 5947506
  • TestTwo: 5947506

sending mail from Batch file

PowerShell comes with a built in command for it. So running directly from a .bat file:

powershell -ExecutionPolicy ByPass -Command Send-MailMessage ^
    -SmtpServer server.address.name ^
    -To [email protected] ^
    -From [email protected] ^
    -Subject Testing ^
    -Body 123

NB -ExecutionPolicy ByPass is only needed if you haven't set up permissions for running PS from CMD

Also for those looking to call it from within powershell, drop everything before -Command [inclusive], and ` will be your escape character (not ^)

Gradient text color

The way this effect works is very simple. The element is given a background which is the gradient. It goes from one color to another depending on the colors and color-stop percentages given for it.

For example, in rainbow text sample (note that I've converted the gradient into the standard syntax):

  • The gradient starts at color #f22 at 0% (that is the left edge of the element). First color is always assumed to start at 0% even though the percentage is not mentioned explicitly.
  • Between 0% to 14.25%, the color changes from #f22 to #f2f gradually. The percenatge is set at 14.25 because there are seven color changes and we are looking for equal splits.
  • At 14.25% (of the container's size), the color will exactly be #f2f as per the gradient specified.
  • Similarly the colors change from one to another depending on the bands specified by color stop percentages. Each band should be a step of 14.25%.

So, we end up getting a gradient like in the below snippet. Now this alone would mean the background applies to the entire element and not just the text.

_x000D_
_x000D_
.rainbow {_x000D_
  background-image: linear-gradient(to right, #f22, #f2f 14.25%, #22f 28.5%, #2ff 42.75%, #2f2 57%, #2f2 71.25%, #ff2 85.5%, #f22);_x000D_
  color: transparent;_x000D_
}
_x000D_
<span class="rainbow">Rainbow text</span>
_x000D_
_x000D_
_x000D_

Since, the gradient needs to be applied only to the text and not to the element on the whole, we need to instruct the browser to clip the background from the areas outside the text. This is done by setting background-clip: text.

(Note that the background-clip: text is an experimental property and is not supported widely.)


Now if you want the text to have a simple 3 color gradient (that is, say from red - orange - brown), we just need to change the linear-gradient specification as follows:

  • First parameter is the direction of the gradient. If the color should be red at left side and brown at the right side then use the direction as to right. If it should be red at right and brown at left then give the direction as to left.
  • Next step is to define the colors of the gradient. Since our gradient should start as red on the left side, just specify red as the first color (percentage is assumed to be 0%).
  • Now, since we have two color changes (red - orange and orange - brown), the percentages must be set as 100 / 2 for equal splits. If equal splits are not required, we can assign the percentages as we wish.
  • So at 50% the color should be orange and then the final color would be brown. The position of the final color is always assumed to be at 100%.

Thus the gradient's specification should read as follows:

background-image: linear-gradient(to right, red, orange 50%, brown).

If we form the gradients using the above mentioned method and apply them to the element, we can get the required effect.

_x000D_
_x000D_
.red-orange-brown {_x000D_
  background-image: linear-gradient(to right, red, orange 50%, brown);_x000D_
  color: transparent;_x000D_
  -webkit-background-clip: text;_x000D_
  background-clip: text;_x000D_
}_x000D_
.green-yellowgreen-yellow-gold {_x000D_
  background-image: linear-gradient(to right, green, yellowgreen 33%, yellow 66%, gold);_x000D_
  color: transparent;_x000D_
  -webkit-background-clip: text;_x000D_
  background-clip: text;_x000D_
}
_x000D_
<span class="red-orange-brown">Red to Orange to Brown</span>_x000D_
_x000D_
<br>_x000D_
_x000D_
<span class="green-yellowgreen-yellow-gold">Green to Yellow-green to Yellow to Gold</span>
_x000D_
_x000D_
_x000D_

Use ffmpeg to add text subtitles

You are trying to mux subtitles as a subtitle stream. It is easy but different syntax is used for MP4 (or M4V) and MKV. In both cases you must specify video and audio codec, or just copy stream if you just want to add subtitle.

MP4:

ffmpeg -i input.mp4 -f srt -i input.srt \
-map 0:0 -map 0:1 -map 1:0 -c:v copy -c:a copy \
-c:s mov_text output.mp4

MKV:

ffmpeg -i input.mp4 -f srt -i input.srt \
-map 0:0 -map 0:1 -map 1:0 -c:v copy -c:a copy \
-c:s srt  output.mkv

Namespace not recognized (even though it is there)

In my case removing/adding that assembly worked.

How to get ID of the last updated row in MySQL?

This is the same method as Salman A's answer, but here's the code you actually need to do it.

First, edit your table so that it will automatically keep track of whenever a row is modified. Remove the last line if you only want to know when a row was initially inserted.

ALTER TABLE mytable
ADD lastmodified TIMESTAMP 
    DEFAULT CURRENT_TIMESTAMP 
    ON UPDATE CURRENT_TIMESTAMP;

Then, to find out the last updated row, you can use this code.

SELECT id FROM mytable ORDER BY lastmodified DESC LIMIT 1;

This code is all lifted from MySQL vs PostgreSQL: Adding a 'Last Modified Time' Column to a Table and MySQL Manual: Sorting Rows. I just assembled it.

how to change onclick event with jquery?

You can easily change the onclick event of an element with jQuery without running the new function with:

$("#id").attr("onclick","new_function_name()");

By writing this line you actually change the onclick attribute of #id.

You can also use:

document.getElementById("id").attribute("onclick","new_function_name()");

Can I do Model->where('id', ARRAY) multiple where conditions?

You can use whereIn which accepts an array as second paramter.

DB:table('table')
   ->whereIn('column', [value, value, value])
   ->get()

You can chain where multiple times.

DB:table('table')->where('column', 'operator', 'value')
    ->where('column', 'operator', 'value')
    ->where('column', 'operator', 'value')
    ->get();

This will use AND operator. if you need OR you can use orWhere method.

For advanced where statements

DB::table('table')
    ->where('column', 'operator', 'value')
    ->orWhere(function($query)
    {
        $query->where('column', 'operator', 'value')
            ->where('column', 'operator', 'value');
    })
    ->get();

Hiding and Showing TabPages in tabControl

Someone merged the C# answer into this one so I have to post my answer here. I didn't love the other solutions so I made a helper class that will make it easier to hide / show your tabs while retaining the order of tabs.

/// <summary>
/// Memorizes the order of tabs upon creation to make hiding / showing tabs more
/// straightforward. Instead of interacting with the TabCollection, use this class
/// instead.
/// </summary>
public class TabPageHelper
{
    private List<TabPage> _allTabs;
    private TabControl.TabPageCollection _tabCollection;
    public Dictionary<string, int> TabOrder { get; private set; }

    public TabPageHelper( TabControl.TabPageCollection tabCollection )
    {
        _allTabs = new List<TabPage>();
        TabOrder = new Dictionary<string, int>();
        foreach ( TabPage tab in tabCollection )
        {
            _allTabs.Add( tab );
        }
        _tabCollection = tabCollection;
        foreach ( int index in Enumerable.Range( 0, tabCollection.Count ) )
        {
            var tab = tabCollection[index];
            TabOrder[tab.Name] = index;
        }
    }

    public void ShowTabPage( string tabText )
    {
        TabPage page = _allTabs
            .Where( t => string.Equals( t.Text, tabText, StringComparison.CurrentCultureIgnoreCase ) )
            .First();
        int tabPageOrder = TabOrder[page.Name];
        if ( !_tabCollection.Contains( page ) )
        {
            _tabCollection.Insert( tabPageOrder, page );
        }
    }

    public void HideTabPage( string tabText )
    {
        TabPage page = _allTabs
            .Where( t => string.Equals( t.Text, tabText, StringComparison.CurrentCultureIgnoreCase ) )
            .First();
        int tabPageOrder = TabOrder[page.Name];
        if ( _tabCollection.Contains( page ) )
        {
            _tabCollection.Remove( page );
        }
    }
}

To use the class, instantiate it in your form load method after initializing your components by passing in the tab control's TabPages property.

public Form1()
{
    InitializeComponent();
    _tabHelper = new TabPageHelper( tabControl1.TabPages );
}

All of your tab pages should exist on application load (ie: in the Design view) because the class will remember the order of the tab pages when hiding / showing. You can hide or show them selectively throughout your application like this:

_tabHelper.HideTabPage("Settings");
_tabHelper.ShowTabPage("Schedule");

What requests do browsers' "F5" and "Ctrl + F5" refreshes generate?

It is up to the browser but they behave in similar ways.

I have tested FF, IE7, Opera and Chrome.

F5 usually updates the page only if it is modified. The browser usually tries to use all types of cache as much as possible and adds an "If-modified-since" header to the request. Opera differs by sending a "Cache-Control: no-cache".

CTRL-F5 is used to force an update, disregarding any cache. IE7 adds an "Cache-Control: no-cache", as does FF, which also adds "Pragma: no-cache". Chrome does a normal "If-modified-since" and Opera ignores the key.

If I remember correctly it was Netscape which was the first browser to add support for cache-control by adding "Pragma: No-cache" when you pressed CTRL-F5.

Edit: Updated table

The table below is updated with information on what will happen when the browser's refresh-button is clicked (after a request by Joel Coehoorn), and the "max-age=0" Cache-control-header.

Updated table, 27 September 2010

+------------------------------------------------------------+
¦  UPDATED   ¦                Firefox 3.x                    ¦
¦27 SEP 2010 ¦  +--------------------------------------------¦
¦            ¦  ¦             MSIE 8, 7                      ¦
¦ Version 3  ¦  ¦  +-----------------------------------------¦
¦            ¦  ¦  ¦          Chrome 6.0                     ¦
¦            ¦  ¦  ¦  +--------------------------------------¦
¦            ¦  ¦  ¦  ¦       Chrome 1.0                     ¦
¦            ¦  ¦  ¦  ¦  +-----------------------------------¦
¦            ¦  ¦  ¦  ¦  ¦    Opera 10, 9                    ¦
¦            ¦  ¦  ¦  ¦  ¦  +--------------------------------¦
¦            ¦  ¦  ¦  ¦  ¦  ¦                                ¦
+------------+--+--+--+--+--+--------------------------------¦
¦          F5¦IM¦I ¦IM¦IM¦C ¦                                ¦
¦    SHIFT-F5¦- ¦- ¦CP¦IM¦- ¦ Legend:                        ¦
¦     CTRL-F5¦CP¦C ¦CP¦IM¦- ¦ I = "If-Modified-Since"        ¦
¦      ALT-F5¦- ¦- ¦- ¦- ¦*2¦ P = "Pragma: No-cache"         ¦
¦    ALTGR-F5¦- ¦I ¦- ¦- ¦- ¦ C = "Cache-Control: no-cache"  ¦
+------------+--+--+--+--+--¦ M = "Cache-Control: max-age=0" ¦
¦      CTRL-R¦IM¦I ¦IM¦IM¦C ¦ - = ignored                    ¦
¦CTRL-SHIFT-R¦CP¦- ¦CP¦- ¦- ¦                                ¦
+------------+--+--+--+--+--¦                                ¦
¦       Click¦IM¦I ¦IM¦IM¦C ¦ With 'click' I refer to a      ¦
¦ Shift-Click¦CP¦I ¦CP¦IM¦C ¦ mouse click on the browsers    ¦
¦  Ctrl-Click¦*1¦C ¦CP¦IM¦C ¦ refresh-icon.                  ¦
¦   Alt-Click¦IM¦I ¦IM¦IM¦C ¦                                ¦
¦ AltGr-Click¦IM¦I ¦- ¦IM¦- ¦                                ¦
+------------------------------------------------------------+

Versions tested:

  • Firefox 3.1.6 and 3.0.6 (WINXP)
  • MSIE 8.0.6001 and 7.0.5730.11 (WINXP)
  • Chrome 6.0.472.63 and 1.0.151.48 (WINXP)
  • Opera 10.62 and 9.61 (WINXP)

Notes:

  1. Version 3.0.6 sends I and C, but 3.1.6 opens the page in a new tab, making a normal request with only "I".

  2. Version 10.62 does nothing. 9.61 might do C unless it was a typo in my old table.

Note about Chrome 6.0.472: If you do a forced reload (like CTRL-F5) it behaves like the url is internally marked to always do a forced reload. The flag is cleared if you go to the address bar and press enter.

Iframe positioning

Try adding the css style property

position:relative;

to the div tag , it works ,

Javascript: console.log to html

A little late to the party, but I took @Hristiyan Dodov's answer a bit further still.

All console methods are now rewired and in case of overflowing text, an optional autoscroll to bottom is included. Colors are now based on the logging method rather than the arguments.

_x000D_
_x000D_
rewireLoggingToElement(_x000D_
    () => document.getElementById("log"),_x000D_
    () => document.getElementById("log-container"), true);_x000D_
_x000D_
function rewireLoggingToElement(eleLocator, eleOverflowLocator, autoScroll) {_x000D_
    fixLoggingFunc('log');_x000D_
    fixLoggingFunc('debug');_x000D_
    fixLoggingFunc('warn');_x000D_
    fixLoggingFunc('error');_x000D_
    fixLoggingFunc('info');_x000D_
_x000D_
    function fixLoggingFunc(name) {_x000D_
        console['old' + name] = console[name];_x000D_
        console[name] = function(...arguments) {_x000D_
            const output = produceOutput(name, arguments);_x000D_
            const eleLog = eleLocator();_x000D_
_x000D_
            if (autoScroll) {_x000D_
                const eleContainerLog = eleOverflowLocator();_x000D_
                const isScrolledToBottom = eleContainerLog.scrollHeight - eleContainerLog.clientHeight <= eleContainerLog.scrollTop + 1;_x000D_
                eleLog.innerHTML += output + "<br>";_x000D_
                if (isScrolledToBottom) {_x000D_
                    eleContainerLog.scrollTop = eleContainerLog.scrollHeight - eleContainerLog.clientHeight;_x000D_
                }_x000D_
            } else {_x000D_
                eleLog.innerHTML += output + "<br>";_x000D_
            }_x000D_
_x000D_
            console['old' + name].apply(undefined, arguments);_x000D_
        };_x000D_
    }_x000D_
_x000D_
    function produceOutput(name, args) {_x000D_
        return args.reduce((output, arg) => {_x000D_
            return output +_x000D_
                "<span class=\"log-" + (typeof arg) + " log-" + name + "\">" +_x000D_
                    (typeof arg === "object" && (JSON || {}).stringify ? JSON.stringify(arg) : arg) +_x000D_
                "</span>&nbsp;";_x000D_
        }, '');_x000D_
    }_x000D_
}_x000D_
_x000D_
_x000D_
setInterval(() => {_x000D_
  const method = (['log', 'debug', 'warn', 'error', 'info'][Math.floor(Math.random() * 5)]);_x000D_
  console[method](method, 'logging something...');_x000D_
}, 200);
_x000D_
#log-container { overflow: auto; height: 150px; }_x000D_
_x000D_
.log-warn { color: orange }_x000D_
.log-error { color: red }_x000D_
.log-info { color: skyblue }_x000D_
.log-log { color: silver }_x000D_
_x000D_
.log-warn, .log-error { font-weight: bold; }
_x000D_
<div id="log-container">_x000D_
  <pre id="log"></pre>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to convert int to float in C?

Change your code to:

int total=0, number=0;
float percentage=0.0f;

percentage=((float)number/total)*100f;
printf("%.2f", (double)percentage);

Msg 102, Level 15, State 1, Line 1 Incorrect syntax near ' '

For the OP's command:

select compid,2, convert(datetime, '01/01/' + CONVERT(char(4),cal_yr) ,101) ,0,  Update_dt, th1, th2, th3_pc , Update_id, Update_dt,1
from  #tmp_CTF** 

I get this error:

Msg 102, Level 15, State 1, Line 2
Incorrect syntax near '*'.

when debugging something like this split the long line up so you'll get a better row number:

select compid
,2
, convert(datetime
, '01/01/' 
+ CONVERT(char(4)
,cal_yr) 
,101) 
,0
,  Update_dt
, th1
, th2
, th3_pc 
, Update_id
, Update_dt
,1
from  #tmp_CTF** 

this now results in:

Msg 102, Level 15, State 1, Line 16
Incorrect syntax near '*'.

which is probably just from the OP not putting the entire command in the question, or use [ ] braces to signify the table name:

from [#tmp_CTF**]

if that is the table name.

Given the lat/long coordinates, how can we find out the city/country?

Loc2country is a Golang based tool that returns the ISO alpha-3 country code for given location coordinates (lat/lon). It responds in microseconds. It uses a geohash to country map.

The geohash data is generated using georaptor.

We use geohash at level 6 for this tool, i.e., boxes of size 1.2km x 600m.

Random alpha-numeric string in JavaScript?

I just came across this as a really nice and elegant solution:

Math.random().toString(36).slice(2)

Notes on this implementation:

  • This will produce a string anywhere between zero and 12 characters long, usually 11 characters, due to the fact that floating point stringification removes trailing zeros.
  • It won't generate capital letters, only lower-case and numbers.
  • Because the randomness comes from Math.random(), the output may be predictable and therefore not necessarily unique.
  • Even assuming an ideal implementation, the output has at most 52 bits of entropy, which means you can expect a duplicate after around 70M strings generated.

How do I add a Fragment to an Activity with a programmatically created content view

After read all Answers I came up with elegant way:

public class MyActivity extends ActionBarActivity {

 Fragment fragment ;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    FragmentManager fm = getSupportFragmentManager();
    fragment = fm.findFragmentByTag("myFragmentTag");
    if (fragment == null) {
        FragmentTransaction ft = fm.beginTransaction();
        fragment =new MyFragment();
        ft.add(android.R.id.content,fragment,"myFragmentTag");
        ft.commit();
    }

}

basically you don't need to add a frameLayout as container of your fragment instead you can add straight the fragment into the android root View container

IMPORTANT: don't use replace fragment as most of the approach shown here, unless you don't mind to lose fragment variable instance state during onrecreation process.

How to find array / dictionary value using key?

It looks like you're writing PHP, in which case you want:

<?
$arr=array('us'=>'United', 'ca'=>'canada');
$key='ca';
echo $arr[$key];
?>

Notice that the ('us'=>'United', 'ca'=>'canada') needs to be a parameter to the array function in PHP.

Most programming languages that support associative arrays or dictionaries use arr['key'] to retrieve the item specified by 'key'

For instance:

Ruby

ruby-1.9.1-p378 > h = {'us' => 'USA', 'ca' => 'Canada' }
 => {"us"=>"USA", "ca"=>"Canada"} 
ruby-1.9.1-p378 > h['ca']
 => "Canada" 

Python

>>> h = {'us':'USA', 'ca':'Canada'}
>>> h['ca']
'Canada'

C#

class P
{
    static void Main()
    {
        var d = new System.Collections.Generic.Dictionary<string, string> { {"us", "USA"}, {"ca", "Canada"}};
        System.Console.WriteLine(d["ca"]);
    }
}

Lua

t = {us='USA', ca='Canada'}
print(t['ca'])
print(t.ca) -- Lua's a little different with tables

How to get multiple selected values of select box in php?

foreach ($_POST["select2"] as $selectedOption)
{    
    echo $selectedOption."\n";  
}

Sniffing/logging your own Android Bluetooth traffic

Also, this might help finding the actual location the btsnoop_hci.log is being saved:

adb shell "cat /etc/bluetooth/bt_stack.conf | grep FileName"

Print line numbers starting at zero using awk

Another option besides awk is nl which allows for options -v for setting starting value and -n <lf,rf,rz> for left, right and right with leading zeros justified. You can also include -s for a field separator such as -s "," for comma separation between line numbers and your data.

In a Unix environment, this can be done as

cat <infile> | ...other stuff... | nl -v 0 -n rz

or simply

nl -v 0 -n rz <infile>

Example:

echo "Here 
are
some 
words" > words.txt

cat words.txt | nl -v 0 -n rz

Out:

000000      Here
000001      are
000002      some
000003      words

Download multiple files as a zip-file using php

This is a working example of making ZIPs in PHP:

$zip = new ZipArchive();
$zip_name = time().".zip"; // Zip name
$zip->open($zip_name,  ZipArchive::CREATE);
foreach ($files as $file) {
  echo $path = "uploadpdf/".$file;
  if(file_exists($path)){
  $zip->addFromString(basename($path),  file_get_contents($path));  
  }
  else{
   echo"file does not exist";
  }
}
$zip->close();

Are multiple `.gitignore`s frowned on?

As a tangential note, one case where the ability to have multiple .gitignore files is very useful is if you want an extra directory in your working copy that you never intend to commit. Just put a 1-byte .gitignore (containing just a single asterisk) in that directory and it will never show up in git status etc.

javax.net.ssl.SSLException: Received fatal alert: protocol_version

public class SecureSocket {
static {
    // System.setProperty("javax.net.debug", "all");
    System.setProperty("https.protocols", "TLSv1,TLSv1.1,TLSv1.2");
}
public static void main(String[] args) {
    String GhitHubSSLFile = "https://raw.githubusercontent.com/Yash-777/SeleniumWebDrivers/master/pom.xml";
    try {
        String str = readCloudFileAsString(GhitHubSSLFile);
                // new String(Files.readAllBytes(Paths.get( "D:/Sample.file" )));

        System.out.println("Cloud File Data : "+ str);
    } catch (IOException e) {
        e.printStackTrace();
    }
}
public static String readCloudFileAsString( String urlStr ) throws java.io.IOException {
    if( urlStr != null && urlStr != "" ) {
        java.io.InputStream s = null;
        String content = null;
        try {
            URL url = new URL( urlStr );
            s = (java.io.InputStream) url.getContent();
            content = IOUtils.toString(s, "UTF-8");
        }  
        }
        return content.toString();
    }
    return null;
}

Factory Reset Help }

css transition opacity fade background

Please note that the problem is not white color. It is because it is being transparent.

When an element is made transparent, all of its child element's opacity; alpha filter in IE 6 7 etc, is changed to the new value.

So you cannot say that it is white!

You can place an element above it, and change that element's transparency to 1 while changing the image's transparency to .2 or what so ever you want to.

How do I force a DIV block to extend to the bottom of a page even if it has no content?

I dont have the code, but I know I did this once using a combination of height:1000px and margin-bottom: -1000px; Try that.

What's the proper way to install pip, virtualenv, and distribute for Python?

Python 3.4 onward

Python 3.3 adds the venv module, and Python 3.4 adds the ensurepip module. This makes bootstrapping pip as easy as:

python -m ensurepip

Perhaps preceded by a call to venv to do so inside a virtual environment.

Guaranteed pip is described in PEP 453.

How do you get the index of the current iteration of a foreach loop?

I wasn't sure what you were trying to do with the index information based on the question. However, in C#, you can usually adapt the IEnumerable.Select method to get the index out of whatever you want. For instance, I might use something like this for whether a value is odd or even.

string[] names = { "one", "two", "three" };
var oddOrEvenByName = names
    .Select((name, index) => new KeyValuePair<string, int>(name, index % 2))
    .ToDictionary(kvp => kvp.Key, kvp => kvp.Value);

This would give you a dictionary by name of whether the item was odd (1) or even (0) in the list.

Why use the INCLUDE clause when creating an index?

If the column is not in the WHERE/JOIN/GROUP BY/ORDER BY, but only in the column list in the SELECT clause is where you use INCLUDE.

The INCLUDE clause adds the data at the lowest/leaf level, rather than in the index tree. This makes the index smaller because it's not part of the tree

INCLUDE columns are not key columns in the index, so they are not ordered. This means it isn't really useful for predicates, sorting etc as I mentioned above. However, it may be useful if you have a residual lookup in a few rows from the key column(s)

Another MSDN article with a worked example

Disable sorting on last column when using jQuery DataTables

for disable sorting on any column in datatable use the following

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

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

so in your case it becomes:

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

Open another application from your own (intent)

    Intent intent = new Intent(Intent.ACTION_MAIN);
    intent.setComponent(ComponentName.unflattenFromString("com.google.android.maps.mytracks/com.google.android.apps.mytracks.MyTracks"));
    intent.addCategory(Intent.CATEGORY_LAUNCHER);
    startActivity(intent);

EDIT :

as suggested in comments, add one line before startActivity(intent);

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

How is malloc() implemented internally?

Simplistically malloc and free work like this:

malloc provides access to a process's heap. The heap is a construct in the C core library (commonly libc) that allows objects to obtain exclusive access to some space on the process's heap.

Each allocation on the heap is called a heap cell. This typically consists of a header that hold information on the size of the cell as well as a pointer to the next heap cell. This makes a heap effectively a linked list.

When one starts a process, the heap contains a single cell that contains all the heap space assigned on startup. This cell exists on the heap's free list.

When one calls malloc, memory is taken from the large heap cell, which is returned by malloc. The rest is formed into a new heap cell that consists of all the rest of the memory.

When one frees memory, the heap cell is added to the end of the heap's free list. Subsequent malloc's walk the free list looking for a cell of suitable size.

As can be expected the heap can get fragmented and the heap manager may from time to time, try to merge adjacent heap cells.

When there is no memory left on the free list for a desired allocation, malloc calls brk or sbrk which are the system calls requesting more memory pages from the operating system.

Now there are a few modification to optimize heap operations.

  • For large memory allocations (typically > 512 bytes, the heap manager may go straight to the OS and allocate a full memory page.
  • The heap may specify a minimum size of allocation to prevent large amounts of fragmentation.
  • The heap may also divide itself into bins one for small allocations and one for larger allocations to make larger allocations quicker.
  • There are also clever mechanisms for optimizing multi-threaded heap allocation.

Reliable way for a Bash script to get the full path to itself

You may try to define the following variable:

CWD="$(cd -P -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P)"

Or you can try the following function in Bash:

realpath () {
  [[ $1 = /* ]] && echo "$1" || echo "$PWD/${1#./}"
}

This function takes one argument. If the argument already has an absolute path, print it as it is, otherwise print $PWD variable + filename argument (without ./ prefix).

Related:

What is considered a good response time for a dynamic, personalized web application?

Our company has a 5 second response time standard limit, and we aim for 2-3 seconds in general. This accounts for 98% of page loads. A few particular tasks are allowed to go up to 15 seconds, but we then mitigate that time by putting up a page and refreshing every 5 seconds telling the user that we are still trying to process the request. That way the user sees that something is happening and doesn't just leave. Although, considering that I work on a website whose users are forced to use for business reasons, they aren't going to leave, but they are capable of complaining quite loudly.

In general, if the processing is going to take more than 5 seconds, put up a temporary page so that the user doesn't lose interest.

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

Are you sure you should be using POST not PUT?

POST is usually used with application/x-www-urlencoded formats. If you are using a REST API, you should maybe be using PUT? If you are uploading a file you probably need to use multipart/form-data. Not always, but usually, that is the right thing to do..

Also you don't seem to be using the credentials to log in - you need to use the Credentials property of the HttpWebRequest object to send the username and password.

Get Absolute Position of element within the window in wpf

I think what BrandonS wants is not the position of the mouse relative to the root element, but rather the position of some descendant element.

For that, there is the TransformToAncestor method:

Point relativePoint = myVisual.TransformToAncestor(rootVisual)
                              .Transform(new Point(0, 0));

Where myVisual is the element that was just double-clicked, and rootVisual is Application.Current.MainWindow or whatever you want the position relative to.

Maximum number of rows of CSV data in excel sheet

In my memory, excel (versions >= 2007) limits the power 2 of 20: 1.048.576 lines.

Csv is over to this boundary, like ordinary text file. So you will be care of the transfer between two formats.

How can I reset eclipse to default settings?

All the setting are stored in .metadata file in your workspace delete this and you are good to go

Default text which won't be shown in drop-down list

Kyle's solution worked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML. Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder. Something like:

<option selected disabled>Choose here</option>

The complete markup should be along these lines:

<select>
    <option selected disabled>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>
</select>

You can take a look at this fiddle, and here's the result:

enter image description here

If you do not want the sort of placeholder text to appear listed in the options once a user clicks on the select box just add the hidden attribute like so:

<select>
    <option selected disabled hidden>Choose here</option>
    <option value="1">One</option>
    <option value="2">Two</option>
    <option value="3">Three</option>
    <option value="4">Four</option>
    <option value="5">Five</option>
</select>

Check the fiddle here and the screenshot below.

enter image description here


Here is the solution:

<select>
    <option style="display:none;" selected>Select language</option>
    <option>Option 1</option>
    <option>Option 2</option>
</select>

How to convert an array into an object using stdClass()

The quick and dirty way is using json_encode and json_decode which will turn the entire array (including sub elements) into an object.

$clasa = json_decode(json_encode($clasa)); //Turn it into an object

The same can be used to convert an object into an array. Simply add , true to json_decode to return an associated array:

$clasa = json_decode(json_encode($clasa), true); //Turn it into an array

An alternate way (without being dirty) is simply a recursive function:

function convertToObject($array) {
    $object = new stdClass();
    foreach ($array as $key => $value) {
        if (is_array($value)) {
            $value = convertToObject($value);
        }
        $object->$key = $value;
    }
    return $object;
}

or in full code:

<?php
    function convertToObject($array) {
        $object = new stdClass();
        foreach ($array as $key => $value) {
            if (is_array($value)) {
                $value = convertToObject($value);
            }
            $object->$key = $value;
        }
        return $object;
    }

    $clasa = array(
            'e1' => array('nume' => 'Nitu', 'prenume' => 'Andrei', 'sex' => 'm', 'varsta' => 23),
            'e2' => array('nume' => 'Nae', 'prenume' => 'Ionel', 'sex' => 'm', 'varsta' => 27),
            'e3' => array('nume' => 'Noman', 'prenume' => 'Alice', 'sex' => 'f', 'varsta' => 22),
            'e4' => array('nume' => 'Geangos', 'prenume' => 'Bogdan', 'sex' => 'm', 'varsta' => 23),
            'e5' => array('nume' => 'Vasile', 'prenume' => 'Mihai', 'sex' => 'm', 'varsta' => 25)
    );

    $obj = convertToObject($clasa);
    print_r($obj);
?>

which outputs (note that there's no arrays - only stdClass's):

stdClass Object
(
    [e1] => stdClass Object
        (
            [nume] => Nitu
            [prenume] => Andrei
            [sex] => m
            [varsta] => 23
        )

    [e2] => stdClass Object
        (
            [nume] => Nae
            [prenume] => Ionel
            [sex] => m
            [varsta] => 27
        )

    [e3] => stdClass Object
        (
            [nume] => Noman
            [prenume] => Alice
            [sex] => f
            [varsta] => 22
        )

    [e4] => stdClass Object
        (
            [nume] => Geangos
            [prenume] => Bogdan
            [sex] => m
            [varsta] => 23
        )

    [e5] => stdClass Object
        (
            [nume] => Vasile
            [prenume] => Mihai
            [sex] => m
            [varsta] => 25
        )

)

So you'd refer to it by $obj->e5->nume.

DEMO

HTML-5 date field shows as "mm/dd/yyyy" in Chrome, even when valid date is set

In chrome to set the value you need to do YYYY-MM-DD i guess because this worked : http://jsfiddle.net/HudMe/6/

So to make it work you need to set the date as 2012-10-01

Ansible playbook shell output

I found using the minimal stdout_callback with ansible-playbook gave similar output to using ad-hoc ansible.

In your ansible.cfg (Note that I'm on OS X so modify the callback_plugins path to suit your install)

stdout_callback     = minimal
callback_plugins    = /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/ansible/plugins/callback

So that a ansible-playbook task like yours

---
-
  hosts: example
  gather_facts: no
  tasks:
    - shell: ps -eo pcpu,user,args | sort -r -k1 | head -n5

Gives output like this, like an ad-hoc command would

example | SUCCESS | rc=0 >>
%CPU USER     COMMAND
 0.2 root     sshd: root@pts/3
 0.1 root     /usr/sbin/CROND -n
 0.0 root     [xfs-reclaim/vda]
 0.0 root     [xfs_mru_cache]

I'm using ansible-playbook 2.2.1.0

Can't access to HttpContext.Current

Have you included the System.Web assembly in the application?

using System.Web;

If not, try specifying the System.Web namespace, for example:

 System.Web.HttpContext.Current

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

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

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

should be:

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

Postgres could not connect to server

If you shut down your system without quitting psql, postgres would not have removed some files.

I didn't find the file postmaster.pid in the location usr/local/var/postgres

So I did the below:

brew services start postgresql

The above command should let you start postgres

findViewById in Fragment

Use

imagebutton = (ImageButton) getActivity().findViewById(R.id.imagebutton1);

imageview = (ImageView) getActivity().findViewById(R.id.imageview1);

it will work

In Bash, how to add "Are you sure [Y/n]" to any command or alias?

Late to the game, but I created yet another variant of the confirm functions of previous answers:

confirm ()
{
    read -r -p "$(echo $@) ? [y/N] " YESNO

    if [ "$YESNO" != "y" ]; then
        echo >&2 "Aborting"
        exit 1
    fi

    CMD="$1"
    shift

    while [ -n "$1" ]; do
        echo -en "$1\0"
        shift
    done | xargs -0 "$CMD" || exit $?
}

To use it:

confirm your_command

Features:

  • prints your command as part of the prompt
  • passes arguments through using the NULL delimiter
  • preserves your command's exit state

Bugs:

  • echo -en works with bash but might fail in your shell
  • might fail if arguments interfere with echo or xargs
  • a zillion other bugs because shell scripting is hard

Node update a specific package

Use npm outdated to see Current and Latest version of all packages.


Then npm i packageName@versionNumber to install specific version : example npm i [email protected].

Or npm i packageName@latest to install latest version : example npm i browser-sync@latest.

How do I POST form data with UTF-8 encoding by using curl?

You CAN use UTF-8 in the POST request, all you need is to specify the charset in your request.

You should use this request:

curl -X POST -H "Content-Type: application/x-www-form-urlencoded; charset=utf-8" --data-ascii "content=derinhält&date=asdf" http://myserverurl.com/api/v1/somemethod

How to install PHP intl extension in Ubuntu 14.04

For php5 on Ubuntu 14.04

sudo apt-get install php5-intl

For php7 on Ubuntu 16.04

sudo apt-get install php7.0-intl

For php7.2 on Ubuntu 18.04

sudo apt-get install php7.2-intl

Anyway restart your apache after

sudo service apache2 restart

IMPORTANT NOTE: Keep in mind that your php in your terminal/command line has NOTHING todo with the php used by the apache webserver!

If the extension is already installed you should try to enable it. Either in the php.ini file or from command line.

Syntax:

php:

phpenmod [mod name]

apache:

a2enmod [mod name]

Override back button to act like home button

Most of the time you need to create a Service to perform something in the background, and your visible Activity simply controls this Service. (I'm sure the Music player works in the same way, so the example in the docs seems a bit misleading.) If that's the case, then your Activity can finish as usual and the Service will still be running.

A simpler approach is to capture the Back button press and call moveTaskToBack(true) as follows:

// 2.0 and above
@Override
public void onBackPressed() {
    moveTaskToBack(true);
}

// Before 2.0
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
        moveTaskToBack(true);
        return true;
    }
    return super.onKeyDown(keyCode, event);
}

I think the preferred option should be for an Activity to finish normally and be able to recreate itself e.g. reading the current state from a Service if needed. But moveTaskToBack can be used as a quick alternative on occasion.

NOTE: as pointed out by Dave below Android 2.0 introduced a new onBackPressed method, and these recommendations on how to handle the Back button.

SQL Server: Get table primary key using sql query

From memory, it's either this

SELECT * FROM sys.objects
WHERE type = 'PK' 
AND  object_id = OBJECT_ID ('tableName')

or this..

SELECT * FROM sys.objects
WHERE type = 'PK' 
AND  parent_object_id = OBJECT_ID ('tableName')

I think one of them should probably work depending on how the data is stored but I am afraid I have no access to SQL to actually verify the same.

Change the Value of h1 Element within a Form with JavaScript

You can also use this

document.querySelector('yourId').innerHTML = 'Content';

C# get string from textbox

The TextBox control has a Text property that you can use to get (or set) the text of the textbox.

How do you add an action to a button programmatically in xcode

Swift answer:

myButton.addTarget(self, action: "click:", for: .touchUpInside)

func click(sender: UIButton) {
    print("click")
}

Documentation: https://developer.apple.com/documentation/uikit/uicontrol/1618259-addtarget

How do I combine the first character of a cell with another cell in Excel?

Personally I like the & function for this

Assuming that you are using cells A1 and A2 for John Smith

=left(a1,1) & b1

If you want to add text between, for example a period

=left(a1,1) & "." & b1

Connect with SSH through a proxy

I was using the following lines in my .ssh/config (which can be replaced by suitable command line parameters) under Ubuntu

Host remhost
  HostName      my.host.com
  User          myuser
  ProxyCommand  nc -v -X 5 -x proxy-ip:1080 %h %p 2> ssh-err.log
  ServerAliveInterval 30
  ForwardX11 yes

When using it with Msys2, after installing gnu-netcat, file ssh-err.log showed that option -X does not exist. nc --help confirmed that, and seemed to show that there is no alternative option to handle proxies.

So I installed openbsd-netcat (pacman removed gnu-netcat after asking, since it conflicted with openbsd-netcat). On a first view, and checking the respective man pages, openbsd-netcat and Ubuntu netcat seem to very similar, in particular regarding options -X and -x. With this, I connected with no problems.

100% width in React Native Flexbox

Style ={{width : "100%"}}

try this:

StyleSheet generated: {
  "width": "80%",
  "textAlign": "center",
  "marginTop": 21.8625,
  "fontWeight": "bold",
  "fontSize": 16,
  "color": "rgb(24, 24, 24)",
  "fontFamily": "Trajan Pro",
  "textShadowColor": "rgba(255, 255, 255, 0.2)",
  "textShadowOffset": {
    "width": 0,
    "height": 0.5
  }
}

How to get a list of MySQL views?

Here's a way to find all the views in every database on your instance:

SELECT TABLE_SCHEMA, TABLE_NAME 
FROM information_schema.tables 
WHERE TABLE_TYPE LIKE 'VIEW';

How to clear radio button in Javascript?

if the id of the radio buttons are 'male' and 'female', value reset can be done by using jquery

$('input[id=male]').attr('checked',false);
$('input[id=female]').attr('checked',false);

Created Button Click Event c#

    public MainWindow()
    {
        // This button needs to exist on your form.
        myButton.Click += myButton_Click;
    }

    void myButton_Click(object sender, RoutedEventArgs e)
    {
        MessageBox.Show("Message here");
        this.Close();
    }

Pass a JavaScript function as parameter

You can use a JSON as well to store and send JS functions.

Check the following:

var myJSON = 
{
    "myFunc1" : function (){
        alert("a");
    }, 
    "myFunc2" : function (functionParameter){
        functionParameter();
    }
}



function main(){
    myJSON.myFunc2(myJSON.myFunc1);
}

This will print 'a'.

The following has the same effect with the above:

var myFunc1 = function (){
    alert('a');
}

var myFunc2 = function (functionParameter){
    functionParameter();
}

function main(){
    myFunc2(myFunc1);
}

Which is also has the same effect with the following:

function myFunc1(){
    alert('a');
}


function myFunc2 (functionParameter){
    functionParameter();
}

function main(){
    myFunc2(myFunc1);
}

And a object paradigm using Class as object prototype:

function Class(){
    this.myFunc1 =  function(msg){
        alert(msg);
    }

    this.myFunc2 = function(callBackParameter){
        callBackParameter('message');
    }
}


function main(){    
    var myClass = new Class();  
    myClass.myFunc2(myClass.myFunc1);
}

How to call javascript from a href?

Edit This will create a link with Edit after clicking on editing a function name as edit will be called.

What is the advantage of using REST instead of non-REST HTTP?

Query-strings can be ignored by search engines.

Choosing a jQuery datagrid plugin?

The three most used and well supported jQuery grid plugins today are SlickGrid, jqGrid and DataTables. See http://wiki.jqueryui.com/Grid-OtherGrids for more info.

Convert an image (selected by path) to base64 string

That way it's simpler, where you pass the image and then pass the format.

private static string ImageToBase64(Image image)
{
    var imageStream = new MemoryStream();
    try
    {           
        image.Save(imageStream, System.Drawing.Imaging.ImageFormat.Bmp);
        imageStream.Position = 0;
        var imageBytes = imageStream.ToArray();
        var ImageBase64 = Convert.ToBase64String(imageBytes);
        return ImageBase64;
    }
    catch (Exception ex)
    {
        return "Error converting image to base64!";
    }
    finally
    {
      imageStream.Dispose;
    }
}

C# Equivalent of SQL Server DataTypes

public static string FromSqlType(string sqlTypeString)
{
    if (! Enum.TryParse(sqlTypeString, out Enums.SQLType typeCode))
    {
        throw new Exception("sql type not found");
    }
    switch (typeCode)
    {
        case Enums.SQLType.varbinary:
        case Enums.SQLType.binary:
        case Enums.SQLType.filestream:
        case Enums.SQLType.image:
        case Enums.SQLType.rowversion:
        case Enums.SQLType.timestamp://?
            return "byte[]";
        case Enums.SQLType.tinyint:
            return "byte";
        case Enums.SQLType.varchar:
        case Enums.SQLType.nvarchar:
        case Enums.SQLType.nchar:
        case Enums.SQLType.text:
        case Enums.SQLType.ntext:
        case Enums.SQLType.xml:
            return "string";
        case Enums.SQLType.@char:
            return "char";
        case Enums.SQLType.bigint:
            return "long";
        case Enums.SQLType.bit:
            return "bool";
        case Enums.SQLType.smalldatetime:
        case Enums.SQLType.datetime:
        case Enums.SQLType.date:
        case Enums.SQLType.datetime2:
            return "DateTime";
        case Enums.SQLType.datetimeoffset:
            return "DateTimeOffset";
        case Enums.SQLType.@decimal:
        case Enums.SQLType.money:
        case Enums.SQLType.numeric:
        case Enums.SQLType.smallmoney:
            return "decimal";
        case Enums.SQLType.@float:
            return "double";
        case Enums.SQLType.@int:
            return "int";
        case Enums.SQLType.real:
            return "Single";
        case Enums.SQLType.smallint:
            return "short";
        case Enums.SQLType.uniqueidentifier:
            return "Guid";
        case Enums.SQLType.sql_variant:
            return "object";
        case Enums.SQLType.time:
            return "TimeSpan";
        default:
            throw new Exception("none equal type");
    }
}

public enum SQLType
{
    varbinary,//(1)
    binary,//(1)
    image,
    varchar,
    @char,
    nvarchar,//(1)
    nchar,//(1)
    text,
    ntext,
    uniqueidentifier,
    rowversion,
    bit,
    tinyint,
    smallint,
    @int,
    bigint,
    smallmoney,
    money,
    numeric,
    @decimal,
    real,
    @float,
    smalldatetime,
    datetime,
    sql_variant,
    table,
    cursor,
    timestamp,
    xml,
    date,
    datetime2,
    datetimeoffset,
    filestream,
    time,
}

Run / Open VSCode from Mac Terminal

I just want to pull out Benjamin Pasero's answer from inside his comment as it seems the best solution. It is the tip given on the Setting up Visual Studio Code page where it says ...

If you want to run VS Code from the terminal, append the following to your ~/.bash_profile file (~/.zshrc in case you use zsh).

code () { VSCODE_CWD="$PWD" open -n -b "com.microsoft.VSCode" --args $* ;}

Now, you can simply type code . in any folder to start editing files in that folder. [Or code test.txt to go to work on the test.txt file]

Tkinter understanding mainloop

while 1:
    root.update()

... is (very!) roughly similar to:

root.mainloop()

The difference is, mainloop is the correct way to code and the infinite loop is subtly incorrect. I suspect, though, that the vast majority of the time, either will work. It's just that mainloop is a much cleaner solution. After all, calling mainloop is essentially this under the covers:

while the_window_has_not_been_destroyed():
    wait_until_the_event_queue_is_not_empty()
    event = event_queue.pop()
    event.handle()

... which, as you can see, isn't much different than your own while loop. So, why create your own infinite loop when tkinter already has one you can use?

Put in the simplest terms possible: always call mainloop as the last logical line of code in your program. That's how Tkinter was designed to be used.

Replace new lines with a comma delimiter with Notepad++?

For Notepad++ 5.9

  1. Press Ctrl+H
  2. Select Search mode Extended(\n, \r, \t, \o, \x...)
  3. Enter Find what: \r\n
  4. Enter Replace with: ,
  5. Replace_All should get the required result.

Simple Digit Recognition OCR in OpenCV-Python

OCR which stands for Optical Character Recognition is a computer vision technique used to identify the different types of handwritten digits that are used in common mathematics. To perform OCR in OpenCV we will use the KNN algorithm which detects the nearest k neighbors of a particular data point and then classifies that data point based on the class type detected for n neighbors.

Data Used


This data contains 5000 handwritten digits where there are 500 digits for every type of digit. Each digit is of 20×20 pixel dimensions. We will split the data such that 250 digits are for training and 250 digits are for testing for every class.

Below is the implementation.




import numpy as np
import cv2
   
      
# Read the image
image = cv2.imread('digits.png')
  
# gray scale conversion
gray_img = cv2.cvtColor(image,
                        cv2.COLOR_BGR2GRAY)
  
# We will divide the image
# into 5000 small dimensions 
# of size 20x20
divisions = list(np.hsplit(i,100) for i in np.vsplit(gray_img,50))
  
# Convert into Numpy array
# of size (50,100,20,20)
NP_array = np.array(divisions)
   
# Preparing train_data
# and test_data.
# Size will be (2500,20x20)
train_data = NP_array[:,:50].reshape(-1,400).astype(np.float32)
  
# Size will be (2500,20x20)
test_data = NP_array[:,50:100].reshape(-1,400).astype(np.float32)
  
# Create 10 different labels 
# for each type of digit
k = np.arange(10)
train_labels = np.repeat(k,250)[:,np.newaxis]
test_labels = np.repeat(k,250)[:,np.newaxis]
   
# Initiate kNN classifier
knn = cv2.ml.KNearest_create()
  
# perform training of data
knn.train(train_data,
          cv2.ml.ROW_SAMPLE, 
          train_labels)
   
# obtain the output from the
# classifier by specifying the
# number of neighbors.
ret, output ,neighbours,
distance = knn.findNearest(test_data, k = 3)
   
# Check the performance and
# accuracy of the classifier.
# Compare the output with test_labels
# to find out how many are wrong.
matched = output==test_labels
correct_OP = np.count_nonzero(matched)
   
#Calculate the accuracy.
accuracy = (correct_OP*100.0)/(output.size)
   
# Display accuracy.
print(accuracy)


Output

91.64


Well, I decided to workout myself on my question to solve the above problem. What I wanted is to implement a simple OCR using KNearest or SVM features in OpenCV. And below is what I did and how. (it is just for learning how to use KNearest for simple OCR purposes).

1) My first question was about letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.

It contains a letter, along with 16 features of that letter.

And this SOF helped me to find it. These 16 features are explained in the paper Letter Recognition Using Holland-Style Adaptive Classifiers. (Although I didn't understand some of the features at the end)

2) Since I knew, without understanding all those features, it is difficult to do that method. I tried some other papers, but all were a little difficult for a beginner.

So I just decided to take all the pixel values as my features. (I was not worried about accuracy or performance, I just wanted it to work, at least with the least accuracy)

I took the below image for my training data:

enter image description here

(I know the amount of training data is less. But, since all letters are of the same font and size, I decided to try on this).

To prepare the data for training, I made a small code in OpenCV. It does the following things:

  1. It loads the image.
  2. Selects the digits (obviously by contour finding and applying constraints on area and height of letters to avoid false detections).
  3. Draws the bounding rectangle around one letter and wait for key press manually. This time we press the digit key ourselves corresponding to the letter in the box.
  4. Once the corresponding digit key is pressed, it resizes this box to 10x10 and saves all 100 pixel values in an array (here, samples) and corresponding manually entered digit in another array(here, responses).
  5. Then save both the arrays in separate .txt files.

At the end of the manual classification of digits, all the digits in the training data (train.png) are labeled manually by ourselves, image will look like below:

enter image description here

Below is the code I used for the above purpose (of course, not so clean):

import sys

import numpy as np
import cv2

im = cv2.imread('pitrain.png')
im3 = im.copy()

gray = cv2.cvtColor(im,cv2.COLOR_BGR2GRAY)
blur = cv2.GaussianBlur(gray,(5,5),0)
thresh = cv2.adaptiveThreshold(blur,255,1,1,11,2)

#################      Now finding Contours         ###################

contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)

samples =  np.empty((0,100))
responses = []
keys = [i for i in range(48,58)]

for cnt in contours:
    if cv2.contourArea(cnt)>50:
        [x,y,w,h] = cv2.boundingRect(cnt)
        
        if  h>28:
            cv2.rectangle(im,(x,y),(x+w,y+h),(0,0,255),2)
            roi = thresh[y:y+h,x:x+w]
            roismall = cv2.resize(roi,(10,10))
            cv2.imshow('norm',im)
            key = cv2.waitKey(0)

            if key == 27:  # (escape to quit)
                sys.exit()
            elif key in keys:
                responses.append(int(chr(key)))
                sample = roismall.reshape((1,100))
                samples = np.append(samples,sample,0)

responses = np.array(responses,np.float32)
responses = responses.reshape((responses.size,1))
print "training complete"

np.savetxt('generalsamples.data',samples)
np.savetxt('generalresponses.data',responses)

Now we enter in to training and testing part.

For the testing part, I used the below image, which has the same type of letters I used for the training phase.

enter image description here

For training we do as follows:

  1. Load the .txt files we already saved earlier
  2. create an instance of the classifier we are using (it is KNearest in this case)
  3. Then we use KNearest.train function to train the data

For testing purposes, we do as follows:

  1. We load the image used for testing
  2. process the image as earlier and extract each digit using contour methods
  3. Draw a bounding box for it, then resize it to 10x10, and store its pixel values in an array as done earlier.
  4. Then we use KNearest.find_nearest() function to find the nearest item to the one we gave. ( If lucky, it recognizes the correct digit.)

I included last two steps (training and testing) in single code below:

import cv2
import numpy as np

#######   training part    ############### 
samples = np.loadtxt('generalsamples.data',np.float32)
responses = np.loadtxt('generalresponses.data',np.float32)
responses = responses.reshape((responses.size,1))

model = cv2.KNearest()
model.train(samples,responses)

############################# testing part  #########################

im = cv2.imread('pi.png')
out = np.zeros(im.shape,np.uint8)
gray = cv2.cvtColor(im,cv2.COLOR_BGR2GRAY)
thresh = cv2.adaptiveThreshold(gray,255,1,1,11,2)

contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)

for cnt in contours:
    if cv2.contourArea(cnt)>50:
        [x,y,w,h] = cv2.boundingRect(cnt)
        if  h>28:
            cv2.rectangle(im,(x,y),(x+w,y+h),(0,255,0),2)
            roi = thresh[y:y+h,x:x+w]
            roismall = cv2.resize(roi,(10,10))
            roismall = roismall.reshape((1,100))
            roismall = np.float32(roismall)
            retval, results, neigh_resp, dists = model.find_nearest(roismall, k = 1)
            string = str(int((results[0][0])))
            cv2.putText(out,string,(x,y+h),0,1,(0,255,0))

cv2.imshow('im',im)
cv2.imshow('out',out)
cv2.waitKey(0)

And it worked, below is the result I got:

enter image description here


Here it worked with 100% accuracy. I assume this is because all the digits are of the same kind and the same size.

But anyway, this is a good start to go for beginners (I hope so).

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

I think in the question and in some of the answers there is a bit of confusion about the meaning of this pseudocode in DOS: IF A IF B X ELSE Y. It does not mean IF(A and B) THEN X ELSE Y, but in fact means IF A( IF B THEN X ELSE Y). If the test of A fails, then he whole of the inner if-else will be ignored.

As one of the answers mentioned, in this case only one of the tests can succeed so the 'else' is not needed, but of course that only works in this example, it isn't a general solution for doing if-else.

There are lots of ways around this. Here is a few ideas, all are quite ugly but hey, this is (or at least was) DOS!

@echo off

set one=1
set two=2

REM Example 1

IF %one%_%two%==1_1 (
   echo Example 1 fails
) ELSE IF %one%_%two%==1_2 (
   echo Example 1 works correctly
) ELSE (
    echo Example 1 fails
)

REM Example 2

set test1result=0
set test2result=0

if %one%==1 if %two%==1 set test1result=1
if %one%==1 if %two%==2 set test2result=1

IF %test1result%==1 (
   echo Example 2 fails
) ELSE IF %test2result%==1 (
   echo Example 2 works correctly
) ELSE (
    echo Example 2 fails
)

REM Example 3

if %one%==1 if %two%==1 (
   echo Example 3 fails
   goto :endoftests
)
if %one%==1 if %two%==2 (
   echo Example 3 works correctly
   goto :endoftests
)
echo Example 3 fails
)
:endoftests

SwiftUI - How do I change the background color of a View?

The code on Scene delegate in Swift UI

Content view background-color

window.rootViewController?.view.backgroundColor = .lightGray

How to copy file from one location to another location?

Use the New Java File classes in Java >=7.

Create the below method and import the necessary libs.

public static void copyFile( File from, File to ) throws IOException {
    Files.copy( from.toPath(), to.toPath() );
} 

Use the created method as below within main:

File dirFrom = new File(fileFrom);
File dirTo = new File(fileTo);

try {
        copyFile(dirFrom, dirTo);
} catch (IOException ex) {
        Logger.getLogger(TestJava8.class.getName()).log(Level.SEVERE, null, ex);
}

NB:- fileFrom is the file that you want to copy to a new file fileTo in a different folder.

Credits - @Scott: Standard concise way to copy a file in Java?

What are valid values for the id attribute in HTML?

Since ES2015 we can as well use -almost- all unicode characters for ID's, if the document charset is set to UTF8.

Test out here: https://mothereff.in/js-variables

enter image description here

Read about: https://mathiasbynens.be/notes/javascript-identifiers-es6

In ES2015, identifiers must start with $, _, or any symbol with the Unicode derived core property ID_Start.

The rest of the identifier can contain $, _, U+200C zero width non-joiner, U+200D zero width joiner, or any symbol with the Unicode derived core property ID_Continue.

_x000D_
_x000D_
const target = document.querySelector("div").id_x000D_
console.log(_x000D_
   target_x000D_
)_x000D_
document.getElementById(target).style.backgroundColor = "black"
_x000D_
div {_x000D_
  border: 1px black solid;_x000D_
  width: 100%;_x000D_
  height: 200px_x000D_
}
_x000D_
<div id="H???????????°?E?????~???????C?^?????????O????????????`??`?M??_????????????????????????????????????H???¯?">
_x000D_
_x000D_
_x000D_


Should you use it? Probably not a good idea!

Read about: https://stackoverflow.com/a/52799593/2494754

Reading an Excel file in PHP

It depends on how you want to use the data in the excel file. If you want to import it into mysql, you could simply save it as a CSV formatted file and then use fgetcsv to parse it.

Select subset of columns in data.table R

Another alternative is to use .SDcols

cols = paste0("V", c(1,2,3,5))
dt[, .SD, .SDcols=-cols]

String to HashMap JAVA

You can do that with Guava's Splitter.MapSplitter:

Map<String, String> properties = Splitter.on(",").withKeyValueSeparator(":").split(inputString);

How to start and stop/pause setInterval?

The reason you're seeing this specific problem:

JSFiddle wraps your code in a function, so start() is not defined in the global scope.

enter image description here


Moral of the story: don't use inline event bindings. Use addEventListener/attachEvent.


Other notes:

Please don't pass strings to setTimeout and setInterval. It's eval in disguise.

Use a function instead, and get cozy with var and white space:

_x000D_
_x000D_
var input = document.getElementById("input"),
  add;

function start() {
  add = setInterval(function() {
    input.value++;
  }, 1000);
}

start();
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<input type="number" id="input" />
<input type="button" onclick="clearInterval(add)" value="stop" />
<input type="button" onclick="start()" value="start" />
_x000D_
_x000D_
_x000D_

How do I return multiple values from a function in C?

I don't know what your string is, but I'm going to assume that it manages its own memory.

You have two solutions:

1: Return a struct which contains all the types you need.

struct Tuple {
    int a;
    string b;
};

struct Tuple getPair() {
    Tuple r = { 1, getString() };
    return r;
}

void foo() {
    struct Tuple t = getPair();
}

2: Use pointers to pass out values.

void getPair(int* a, string* b) {
    // Check that these are not pointing to NULL
    assert(a);
    assert(b);
    *a = 1;
    *b = getString();
}

void foo() {
    int a, b;
    getPair(&a, &b);
}

Which one you choose to use depends largely on personal preference as to whatever semantics you like more.

Understanding CUDA grid dimensions, block dimensions and threads organization (simple explanation)

Hardware

If a GPU device has, for example, 4 multiprocessing units, and they can run 768 threads each: then at a given moment no more than 4*768 threads will be really running in parallel (if you planned more threads, they will be waiting their turn).

Software

threads are organized in blocks. A block is executed by a multiprocessing unit. The threads of a block can be indentified (indexed) using 1Dimension(x), 2Dimensions (x,y) or 3Dim indexes (x,y,z) but in any case xyz <= 768 for our example (other restrictions apply to x,y,z, see the guide and your device capability).

Obviously, if you need more than those 4*768 threads you need more than 4 blocks. Blocks may be also indexed 1D, 2D or 3D. There is a queue of blocks waiting to enter the GPU (because, in our example, the GPU has 4 multiprocessors and only 4 blocks are being executed simultaneously).

Now a simple case: processing a 512x512 image

Suppose we want one thread to process one pixel (i,j).

We can use blocks of 64 threads each. Then we need 512*512/64 = 4096 blocks (so to have 512x512 threads = 4096*64)

It's common to organize (to make indexing the image easier) the threads in 2D blocks having blockDim = 8 x 8 (the 64 threads per block). I prefer to call it threadsPerBlock.

dim3 threadsPerBlock(8, 8);  // 64 threads

and 2D gridDim = 64 x 64 blocks (the 4096 blocks needed). I prefer to call it numBlocks.

dim3 numBlocks(imageWidth/threadsPerBlock.x,  /* for instance 512/8 = 64*/
              imageHeight/threadsPerBlock.y); 

The kernel is launched like this:

myKernel <<<numBlocks,threadsPerBlock>>>( /* params for the kernel function */ );       

Finally: there will be something like "a queue of 4096 blocks", where a block is waiting to be assigned one of the multiprocessors of the GPU to get its 64 threads executed.

In the kernel the pixel (i,j) to be processed by a thread is calculated this way:

uint i = (blockIdx.x * blockDim.x) + threadIdx.x;
uint j = (blockIdx.y * blockDim.y) + threadIdx.y;

Modify property value of the objects in list using Java 8 streams

If you wanna create new list, use Stream.map method:

List<Fruit> newList = fruits.stream()
    .map(f -> new Fruit(f.getId(), f.getName() + "s", f.getCountry()))
    .collect(Collectors.toList())

If you wanna modify current list, use Collection.forEach:

fruits.forEach(f -> f.setName(f.getName() + "s"))

Android turn On/Off WiFi HotSpot programmatically

For Android 8.0, there is a new API to handle Hotspots. As far as I know, the old way using reflection doesn't work anymore. Please refer to:

Android Developers https://developer.android.com/reference/android/net/wifi/WifiManager.html#startLocalOnlyHotspot(android.net.wifi.WifiManager.LocalOnlyHotspotCallback,%20android.os.Handler)

void startLocalOnlyHotspot (WifiManager.LocalOnlyHotspotCallback callback, 
                Handler handler)

Request a local only hotspot that an application can use to communicate between co-located devices connected to the created WiFi hotspot. The network created by this method will not have Internet access.

Stack Overflow
How to turn on/off wifi hotspot programmatically in Android 8.0 (Oreo)

onStarted(WifiManager.LocalOnlyHotspotReservation reservation) method will be called if hotspot is turned on.. Using WifiManager.LocalOnlyHotspotReservation reference you call close() method to turn off hotspot.

How do I create a view controller file after creating a new view controller?

To add new ViewController once you have have an existing ViewController, follow below step:

  1. Click on background of Main.storyboard.

  2. Search and select ViewController from object library at the utility window.

  3. Drag and drop it in background to create a new ViewController.

Extract a single (unsigned) integer from a string

for utf8 str:

function unicodeStrDigits($str) {
    $arr = array();
    $sub = '';
    for ($i = 0; $i < strlen($str); $i++) { 
        if (is_numeric($str[$i])) {
            $sub .= $str[$i];
            continue;
        } else {
            if ($sub) {
                array_push($arr, $sub);
                $sub = '';
            }
        }
    }

    if ($sub) {
        array_push($arr, $sub); 
    }

    return $arr;
}

Make an image follow mouse pointer

Ok, here's a simple box that follows the cursor

Doing the rest is a simple case of remembering the last cursor position and applying a formula to get the box to move other than exactly where the cursor is. A timeout would also be handy if the box has a limited acceleration and must catch up to the cursor after it stops moving. Replacing the box with an image is simple CSS (which can replace most of the setup code for the box). I think the actual thinking code in the example is about 8 lines.

Select the right image (use a sprite) to orientate the rocket.

Yeah, annoying as hell. :-)

_x000D_
_x000D_
function getMouseCoords(e) {
  var e = e || window.event;
  document.getElementById('container').innerHTML = e.clientX + ', ' +
    e.clientY + '<br>' + e.screenX + ', ' + e.screenY;
}


var followCursor = (function() {
  var s = document.createElement('div');
  s.style.position = 'absolute';
  s.style.margin = '0';
  s.style.padding = '5px';
  s.style.border = '1px solid red';
  s.textContent = ""

  return {
    init: function() {
      document.body.appendChild(s);
    },

    run: function(e) {
      var e = e || window.event;
      s.style.left = (e.clientX - 5) + 'px';
      s.style.top = (e.clientY - 5) + 'px';
      getMouseCoords(e);
    }
  };
}());

window.onload = function() {
  followCursor.init();
  document.body.onmousemove = followCursor.run;
}
_x000D_
#container {
  width: 1000px;
  height: 1000px;
  border: 1px solid blue;
}
_x000D_
<div id="container"></div>
_x000D_
_x000D_
_x000D_

File Permissions and CHMOD: How to set 777 in PHP upon file creation?

If you want to change the permissions of an existing file, use chmod (change mode):

$itWorked = chmod ("/yourdir/yourfile", 0777);

If you want all new files to have certain permissions, you need to look into setting your umode. This is a process setting that applies a default modification to standard modes.

It is a subtractive one. By that, I mean a umode of 022 will give you a default permission of 755 (777 - 022 = 755).

But you should think very carefully about both these options. Files created with that mode will be totally unprotected from changes.

Laravel 5 - redirect to HTTPS

This is for Larave 5.2.x and greater. If you want to have an option to serve some content over HTTPS and others over HTTP here is a solution that worked for me. You may wonder, why would someone want to serve only some content over HTTPS? Why not serve everything over HTTPS?

Although, it's totally fine to serve the whole site over HTTPS, severing everything over HTTPS has an additional overhead on your server. Remember encryption doesn't come cheap. The slight overhead also has an impact on your app response time. You could argue that commodity hardware is cheap and the impact is negligible but I digress :) I don't like the idea of serving marketing content big pages with images etc over https. So here it goes. It's similar to what others have suggest above using middleware but it's a full solution that allows you to toggle back and forth between HTTP/HTTPS.

First create a middleware.

php artisan make:middleware ForceSSL

This is what your middleware should look like.

<?php

namespace App\Http\Middleware;

use Closure;

class ForceSSL
{

    public function handle($request, Closure $next)
    {

        if (!$request->secure()) {
            return redirect()->secure($request->getRequestUri());
        }

        return $next($request);
    }
}

Note that I'm not filtering based on environment because I have HTTPS setup for both local dev and production so there is not need to.

Add the following to your routeMiddleware \App\Http\Kernel.php so that you can pick and choose which route group should force SSL.

    protected $routeMiddleware = [
    'auth' => \App\Http\Middleware\Authenticate::class,
    'auth.basic' => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
    'can' => \Illuminate\Foundation\Http\Middleware\Authorize::class,
    'guest' => \App\Http\Middleware\RedirectIfAuthenticated::class,
    'throttle' => \Illuminate\Routing\Middleware\ThrottleRequests::class,
    'forceSSL' => \App\Http\Middleware\ForceSSL::class,
];

Next, I'd like to secure two basic groups login/signup etc and everything else behind Auth middleware.

Route::group(array('middleware' => 'forceSSL'), function() {
/*user auth*/
Route::get('login', 'AuthController@showLogin');
Route::post('login', 'AuthController@doLogin');

// Password reset routes...
Route::get('password/reset/{token}', 'Auth\PasswordController@getReset');
Route::post('password/reset', 'Auth\PasswordController@postReset');

//other routes like signup etc

});


Route::group(['middleware' => ['auth','forceSSL']], function()
 {
Route::get('dashboard', function(){
    return view('app.dashboard');
});
Route::get('logout', 'AuthController@doLogout');

//other routes for your application
});

Confirm that your middlewares are applied to your routes properly from console.

php artisan route:list

Now you have secured all the forms or sensitive areas of your application, the key now is to use your view template to define your secure and public (non https) links.

Based on the example above you would render your secure links as follows -

<a href="{{secure_url('/login')}}">Login</a>
<a href="{{secure_url('/signup')}}">SignUp</a>

Non secure links can be rendered as

<a href="{{url('/aboutus',[],false)}}">About US</a></li>
<a href="{{url('/promotion',[],false)}}">Get the deal now!</a></li>

What this does is renders a fully qualified URL such as https://yourhost/login and http://yourhost/aboutus

If you were not render fully qualified URL with http and use a relative link url('/aboutus') then https would persists after a user visits a secure site.

Hope this helps!

Make Https call using HttpClient

If the server only supports higher TLS version like TLS 1.2 only, it will still fail unless your client PC is configured to use higher TLS version by default. To overcome this problem add the following in your code.

System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

Modifying your example code, it would be

HttpClient httpClient = new HttpClient();   

//specify to use TLS 1.2 as default connection
System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

httpClient.BaseAddress = new Uri("https://foobar.com/");
httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/xml"));

var task = httpClient.PostAsXmlAsync<DeviceRequest>("api/SaveData", request);

How do I get formatted JSON in .NET using C#?

You may use following standard method for getting formatted Json

JsonReaderWriterFactory.CreateJsonWriter(Stream stream, Encoding encoding, bool ownsStream, bool indent, string indentChars)

Only set "indent==true"

Try something like this

    public readonly DataContractJsonSerializerSettings Settings = 
            new DataContractJsonSerializerSettings
            { UseSimpleDictionaryFormat = true };

    public void Keep<TValue>(TValue item, string path)
    {
        try
        {
            using (var stream = File.Open(path, FileMode.Create))
            {
                //var currentCulture = Thread.CurrentThread.CurrentCulture;
                //Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;

                try
                {
                    using (var writer = JsonReaderWriterFactory.CreateJsonWriter(
                        stream, Encoding.UTF8, true, true, "  "))
                    {
                        var serializer = new DataContractJsonSerializer(type, Settings);
                        serializer.WriteObject(writer, item);
                        writer.Flush();
                    }
                }
                catch (Exception exception)
                {
                    Debug.WriteLine(exception.ToString());
                }
                finally
                {
                    //Thread.CurrentThread.CurrentCulture = currentCulture;
                }
            }
        }
        catch (Exception exception)
        {
            Debug.WriteLine(exception.ToString());
        }
    }

Pay your attention to lines

    var currentCulture = Thread.CurrentThread.CurrentCulture;
    Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
    ....
    Thread.CurrentThread.CurrentCulture = currentCulture;

For some kinds of xml-serializers you should use InvariantCulture to avoid exception during deserialization on the computers with different Regional settings. For example, invalid format of double or DateTime sometimes cause them.

For deserializing

    public TValue Revive<TValue>(string path, params object[] constructorArgs)
    {
        try
        {
            using (var stream = File.OpenRead(path))
            {
                //var currentCulture = Thread.CurrentThread.CurrentCulture;
                //Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;

                try
                {
                    var serializer = new DataContractJsonSerializer(type, Settings);
                    var item = (TValue) serializer.ReadObject(stream);
                    if (Equals(item, null)) throw new Exception();
                    return item;
                }
                catch (Exception exception)
                {
                    Debug.WriteLine(exception.ToString());
                    return (TValue) Activator.CreateInstance(type, constructorArgs);
                }
                finally
                {
                    //Thread.CurrentThread.CurrentCulture = currentCulture;
                }
            }
        }
        catch
        {
            return (TValue) Activator.CreateInstance(typeof (TValue), constructorArgs);
        }
    }

Thanks!

How do I create sql query for searching partial matches?

This may work as well.

SELECT * 
FROM myTable
WHERE CHARINDEX('mall', name) > 0
  OR CHARINDEX('mall', description) > 0

What is the purpose of flush() in Java streams?

When you write data to a stream, it is not written immediately, and it is buffered. So use flush() when you need to be sure that all your data from buffer is written.

We need to be sure that all the writes are completed before we close the stream, and that is why flush() is called in file/buffered writer's close().

But if you have a requirement that all your writes be saved anytime before you close the stream, use flush().

How to create RecyclerView with multiple view type?

You can use the library: https://github.com/vivchar/RendererRecyclerViewAdapter

mRecyclerViewAdapter = new RendererRecyclerViewAdapter(); /* included from library */
mRecyclerViewAdapter.registerRenderer(new SomeViewRenderer(SomeModel.TYPE, this));
mRecyclerViewAdapter.registerRenderer(...); /* you can use several types of cells */

`

For each item, you should to implement a ViewRenderer, ViewHolder, SomeModel:

ViewHolder - it is a simple view holder of recycler view.

SomeModel - it is your model with ItemModel interface

public class SomeViewRenderer extends ViewRenderer<SomeModel, SomeViewHolder> {

  public SomeViewRenderer(final int type, final Context context) {
    super(type, context);
  }
  @Override
 public void bindView(@NonNull final SomeModel model, @NonNull final SomeViewHolder holder) {
    holder.mTitle.setText(model.getTitle());
 }
 @NonNull
 @Override
 public SomeViewHolder createViewHolder(@Nullable final ViewGroup parent) {
    return new SomeViewHolder(LayoutInflater.from(getContext()).inflate(R.layout.some_item, parent, false));
 }
}

For more details you can look documentations.

how to attach url link to an image?

Alternatively,

<style type="text/css">
#example {
    display: block;
    width: 30px;
    height: 10px;
    background: url(../images/example.png) no-repeat;
    text-indent: -9999px;
}
</style>

<a href="http://www.example.com" id="example">See an example!</a>

More wordy, but it may benefit SEO, and it will look like nice simple text with CSS disabled.

How to fix Cannot find module 'typescript' in Angular 4?

If you have cloned your project from git or somewhere then first, you should type npm install.

Python code to remove HTML tags from a string

There's a simple way to this in any C-like language. The style is not Pythonic but works with pure Python:

def remove_html_markup(s):
    tag = False
    quote = False
    out = ""

    for c in s:
            if c == '<' and not quote:
                tag = True
            elif c == '>' and not quote:
                tag = False
            elif (c == '"' or c == "'") and tag:
                quote = not quote
            elif not tag:
                out = out + c

    return out

The idea based in a simple finite-state machine and is detailed explained here: http://youtu.be/2tu9LTDujbw

You can see it working here: http://youtu.be/HPkNPcYed9M?t=35s

PS - If you're interested in the class(about smart debugging with python) I give you a link: https://www.udacity.com/course/software-debugging--cs259. It's free!

Export DataTable to Excel File

Most answers are actually producing the CSV which I don't always have good experience with, when opening in Excel.

One way of doing it would be also with ACE OLEDB Provider (see also connection strings for Excel). Of course you'd have to have the provider installed and registered. You do have it, if you have Excel installed, but this is something you have to consider when deploying (e.g. on web server).

In below helper class code you'd have to call something like ExportHelper.CreateXlsFromDataTable(dataset.Tables[0], @"C:\tmp\export.xls");

public class ExportHelper
{
    private const string ExcelOleDbConnectionStringTemplate = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Extended Properties=\"Excel 8.0;HDR=YES\";";

    /// <summary>
    /// Creates the Excel file from items in DataTable and writes them to specified output file.
    /// </summary>
    public static void CreateXlsFromDataTable(DataTable dataTable, string fullFilePath)
    {
        string createTableWithHeaderScript = GenerateCreateTableCommand(dataTable);

        using (var conn = new OleDbConnection(String.Format(ExcelOleDbConnectionStringTemplate, fullFilePath)))
        {
            if (conn.State != ConnectionState.Open)
            {
                conn.Open();
            }

            OleDbCommand cmd = new OleDbCommand(createTableWithHeaderScript, conn);
            cmd.ExecuteNonQuery();

            foreach (DataRow dataExportRow in dataTable.Rows)
            {
                AddNewRow(conn, dataExportRow);
            }
        }
    }

    private static void AddNewRow(OleDbConnection conn, DataRow dataRow)
    {
        string insertCmd = GenerateInsertRowCommand(dataRow);

        using (OleDbCommand cmd = new OleDbCommand(insertCmd, conn))
        {
            AddParametersWithValue(cmd, dataRow);
            cmd.ExecuteNonQuery();
        }
    }

    /// <summary>
    /// Generates the insert row command.
    /// </summary>
    private static string GenerateInsertRowCommand(DataRow dataRow)
    {
        var stringBuilder = new StringBuilder();
        var columns = dataRow.Table.Columns.Cast<DataColumn>().ToList();
        var columnNamesCommaSeparated = string.Join(",", columns.Select(x => x.Caption));
        var questionmarkCommaSeparated = string.Join(",", columns.Select(x => "?"));

        stringBuilder.AppendFormat("INSERT INTO [{0}] (", dataRow.Table.TableName);
        stringBuilder.Append(columnNamesCommaSeparated);
        stringBuilder.Append(") VALUES(");
        stringBuilder.Append(questionmarkCommaSeparated);
        stringBuilder.Append(")");
        return stringBuilder.ToString();
    }

    /// <summary>
    /// Adds the parameters with value.
    /// </summary>
    private static void AddParametersWithValue(OleDbCommand cmd, DataRow dataRow)
    {
        var paramNumber = 1;

        for (int i = 0; i <= dataRow.Table.Columns.Count - 1; i++)
        {
            if (!ReferenceEquals(dataRow.Table.Columns[i].DataType, typeof(int)) && !ReferenceEquals(dataRow.Table.Columns[i].DataType, typeof(decimal)))
            {
                cmd.Parameters.AddWithValue("@p" + paramNumber, dataRow[i].ToString().Replace("'", "''"));
            }
            else
            {
                object value = GetParameterValue(dataRow[i]);
                OleDbParameter parameter = cmd.Parameters.AddWithValue("@p" + paramNumber, value);
                if (value is decimal)
                {
                    parameter.OleDbType = OleDbType.Currency;
                }
            }

            paramNumber = paramNumber + 1;
        }
    }

    /// <summary>
    /// Gets the formatted value for the OleDbParameter.
    /// </summary>
    private static object GetParameterValue(object value)
    {
        if (value is string)
        {
            return value.ToString().Replace("'", "''");
        }
        return value;
    }

    private static string GenerateCreateTableCommand(DataTable tableDefination)
    {
        StringBuilder stringBuilder = new StringBuilder();
        bool firstcol = true;

        stringBuilder.AppendFormat("CREATE TABLE [{0}] (", tableDefination.TableName);

        foreach (DataColumn tableColumn in tableDefination.Columns)
        {
            if (!firstcol)
            {
                stringBuilder.Append(", ");
            }
            firstcol = false;

            string columnDataType = "CHAR(255)";

            switch (tableColumn.DataType.Name)
            {
                case "String":
                    columnDataType = "CHAR(255)";
                    break;
                case "Int32":
                    columnDataType = "INTEGER";
                    break;
                case "Decimal":
                    // Use currency instead of decimal because of bug described at 
                    // http://social.msdn.microsoft.com/Forums/vstudio/en-US/5d6248a5-ef00-4f46-be9d-853207656bcc/localization-trouble-with-oledbparameter-and-decimal?forum=csharpgeneral
                    columnDataType = "CURRENCY";
                    break;
            }

            stringBuilder.AppendFormat("{0} {1}", tableColumn.ColumnName, columnDataType);
        }
        stringBuilder.Append(")");

        return stringBuilder.ToString();
    }
}

How do I import a CSV file in R?

You would use the read.csv function; for example:

dat = read.csv("spam.csv", header = TRUE)

You can also reference this tutorial for more details.

Note: make sure the .csv file to read is in your working directory (using getwd()) or specify the right path to file. If you want, you can set the current directory using setwd.

How to disassemble a memory range with GDB?

gdb disassemble has a /m to include source code alongside the instructions. This is equivalent of objdump -S, with the extra benefit of confining to just the one function (or address-range) of interest.

How to get the real and total length of char * (char array)?

char *a = new char[10];

My question is that how can I get the length of a char *

It is very simply.:) It is enough to add only one statement

size_t N = 10;
char *a = new char[N];

Now you can get the size of the allocated array

std::cout << "The size is " << N << std::endl;

Many mentioned here C standard function std::strlen. But it does not return the actual size of a character array. It returns only the size of stored string literal.

The difference is the following. if to take your code snippet as an example

char a[] = "aaaaa";
int length = sizeof(a)/sizeof(char); // length=6

then std::strlen( a ) will return 5 instead of 6 as in your code.

So the conclusion is simple: if you need to dynamically allocate a character array consider usage of class std::string. It has methof size and its synonym length that allows to get the size of the array at any time.

For example

std::string s( "aaaaa" );

std::cout << s.length() << std::endl;

or

std::string s;
s.resize( 10 );

std::cout << s.length() << std::endl;

Shared folder between MacOSX and Windows on Virtual Box

Using a Windows 10 guest, after I performed steps 1 through 3 from @xinampc's answer, I had to open a new File Explorer and navigated to This PC > CD Drive (D:) VirtualBox Guest Additions to run VBoxWindowsAdditions. After I ran that and went through the command prompts, Windows rebooted and I was able to see VBOXSVR under Network.

How to align text below an image in CSS?

Add a container div for the image and the caption:

<div class="item">
    <img src=""/>
    <span class="caption">Text below the image</span>
</div>

Then, with a bit of CSS, you can make an automatically wrapping image gallery:

div.item {
    vertical-align: top;
    display: inline-block;
    text-align: center;
    width: 120px;
}
img {
    width: 100px;
    height: 100px;
    background-color: grey;
}
.caption {
    display: block;
}

_x000D_
_x000D_
div.item {_x000D_
    /* To correctly align image, regardless of content height: */_x000D_
    vertical-align: top;_x000D_
    display: inline-block;_x000D_
    /* To horizontally center images and caption */_x000D_
    text-align: center;_x000D_
    /* The width of the container also implies margin around the images. */_x000D_
    width: 120px;_x000D_
}_x000D_
img {_x000D_
    width: 100px;_x000D_
    height: 100px;_x000D_
    background-color: grey;_x000D_
}_x000D_
.caption {_x000D_
    /* Make the caption a block so it occupies its own line. */_x000D_
    display: block;_x000D_
}
_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">Text below the image</span>_x000D_
</div>_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">Text below the image</span>_x000D_
</div>_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">An even longer text below the image which should take up multiple lines.</span>_x000D_
</div>_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">Text below the image</span>_x000D_
</div>_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">Text below the image</span>_x000D_
</div>_x000D_
<div class="item">_x000D_
    <img src=""/>_x000D_
    <span class="caption">An even longer text below the image which should take up multiple lines.</span>_x000D_
</div>
_x000D_
_x000D_
_x000D_

http://jsfiddle.net/ZhLk4/1/

Updated answer

Instead of using 'anonymous' div and spans, you can also use the HTML5 figure and figcaption elements. The advantage is that these tags add to the semantic structure of the document. Visually there is no difference, but it may (positively) affect the usability and indexability of your pages.

The tags are different, but the structure of the code is exactly the same, as you can see in this updated snippet and fiddle:

<figure class="item">
    <img src=""/>
    <figcaption class="caption">Text below the image</figcaption>
</figure>

_x000D_
_x000D_
figure.item {_x000D_
    /* To correctly align image, regardless of content height: */_x000D_
    vertical-align: top;_x000D_
    display: inline-block;_x000D_
    /* To horizontally center images and caption */_x000D_
    text-align: center;_x000D_
    /* The width of the container also implies margin around the images. */_x000D_
    width: 120px;_x000D_
}_x000D_
img {_x000D_
    width: 100px;_x000D_
    height: 100px;_x000D_
    background-color: grey;_x000D_
}_x000D_
.caption {_x000D_
    /* Make the caption a block so it occupies its own line. */_x000D_
    display: block;_x000D_
}
_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">Text below the image</figcaption>_x000D_
</figure>_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">Text below the image</figcaption>_x000D_
</figure>_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">An even longer text below the image which should take up multiple lines.</figcaption>_x000D_
</figure>_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">Text below the image</figcaption>_x000D_
</figure>_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">Text below the image</figcaption>_x000D_
</figure>_x000D_
<figure class="item">_x000D_
    <img src=""/>_x000D_
    <figcaption class="caption">An even longer text below the image which should take up multiple lines.</figcaption>_x000D_
</figure>
_x000D_
_x000D_
_x000D_

http://jsfiddle.net/ZhLk4/379/

Merging Cells in Excel using C#

Excel.Application xl = new Excel.ApplicationClass();

Excel.Workbook wb = xl.Workbooks.Add(Excel.XlWBATemplate.xlWBATWorkshe et);

Excel.Worksheet ws = (Excel.Worksheet)wb.ActiveSheet;

ws.Cells[1,1] = "Testing";

Excel.Range range = ws.get_Range(ws.Cells[1,1],ws.Cells[1,2]);

range.Merge(true);

range.Interior.ColorIndex =36;

xl.Visible =true;

Set timeout for ajax (jQuery)

Please read the $.ajax documentation, this is a covered topic.

$.ajax({
    url: "test.html",
    error: function(){
        // will fire when timeout is reached
    },
    success: function(){
        //do something
    },
    timeout: 3000 // sets timeout to 3 seconds
});

You can get see what type of error was thrown by accessing the textStatus parameter of the error: function(jqXHR, textStatus, errorThrown) option. The options are "timeout", "error", "abort", and "parsererror".

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

VMware does not allow you to run a 64-bit guest on a 32-bit host. You just have to read the documentation to find this out.

If you really want to do this, you can use QEMU, and I recommend a Linux host, but it's going to be very slow (I really mean slow).

Setting "checked" for a checkbox with jQuery

$('controlCheckBox').click(function(){
    var temp = $(this).prop('checked');
    $('controlledCheckBoxes').prop('checked', temp);
});