Programs & Examples On #Html safe

How to go to a URL using jQuery?

why not using?

location.href='http://www.example.com';

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<!DOCTYPE html>_x000D_
<html>_x000D_
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<head>_x000D_
  <script>_x000D_
    function goToURL() {_x000D_
      location.href = 'http://google.it';_x000D_
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    }_x000D_
  </script>_x000D_
</head>_x000D_
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<body>_x000D_
  <a href="javascript:void(0)" onclick="goToURL(); return false;">Go To URL</a>_x000D_
</body>_x000D_
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</html>
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Having trouble setting working directory

Maybe it is the case that you have your path in couple of lines, you used enter to make it? If so, then part of you paths might look like that "/\nData/" instead of "/Data/", which causes the problem. Just set it to be in one line and issue is solved!

Converting File to MultiPartFile

Solution without Mocking class, Java9+ and Spring only.

FileItem fileItem = new DiskFileItemFactory().createItem("file",
    Files.probeContentType(file.toPath()), false, file.getName());

try (InputStream in = new FileInputStream(file); OutputStream out = fileItem.getOutputStream()) {
    in.transferTo(out);
} catch (Exception e) {
    throw new IllegalArgumentException("Invalid file: " + e, e);
}

CommonsMultipartFile multipartFile = new CommonsMultipartFile(fileItem);

how to fix EXE4J_JAVA_HOME, No JVM could be found on your system error?

This has to be done during your exe4j configuration. In the fourth step of Exe4j wizard which is Executable Info select> Advanced options select 32-bit or 64-bit. This worked well for me. or else install both JDK tool-kits x64 and x32 in your machine.

Find text string using jQuery?

Take a look at highlight (jQuery plugin).

PHP: How to get current time in hour:minute:second?

You can combine both in the same date function call

date("d-m-Y H:i:s");  

How do I force a vertical scrollbar to appear?

Give your body tag an overflow: scroll;

body {
    overflow: scroll;
}

or if you only want a vertical scrollbar use overflow-y

body {
    overflow-y: scroll;
}

No module named Image

Problem:

~$ simple-image-reducer

Traceback (most recent call last):

  File "/usr/bin/simple-image-reducer", line 28, in <module>
    import Image

**ImportError: No module named Image**

Reason:

Image != image

Solution:

1) make sure it is available

python -m pip install  Image

2) where is it available?

sudo find ~ -name image -type d

-->> directory /home/MyHomeDir/.local/lib/python2.7/site-packages/image ->> OK

3) make simple-image-reducer understand via link:

ln -s ~/.local/lib/python2.7/site-packages/image
~/.local/lib/python2.7/site-packages/Image

4) invoke simple-image-reducer again. Works:-)

Eclipse error: 'Failed to create the Java Virtual Machine'

Try to add

-vm
D:\Java\jdk1.6.0_29\bin\javaw.exe

FYI: Refer sunblog

For others who might have problems with Java 7, as per Eclipse Wiki - eclipse.ini vm_value (windows example)

This might not work on all systems. If you encounter "Java was started but returned exit code=1" error while starting the eclipse, modify the -vm argument to point to jvm.dll

e.g.

-vm
C:\Program Files\Java\jre7\bin\client\jvm.dll

Also note that

The -vm option must occur before the -vmargs option, since everything after -vmargs is passed directly to the JVM

Install specific version using laravel installer

use

laravel new blog --version

Example laravel new blog --5.1

You can also use the composer method

composer create-project laravel/laravel app "5.1.*"

here, app is the name of your project

please see the documentation for laravel 5.1 here

UPDATE:

The above commands are no longer supports so please use

composer create-project laravel/laravel="5.1.*" appName

jQuery - adding elements into an array

Try this, at the end of the each loop, ids array will contain all the hexcodes.

var ids = [];

    $(document).ready(function($) {
    var $div = $("<div id='hexCodes'></div>").appendTo(document.body), code;
    $(".color_cell").each(function() {
        code = $(this).attr('id');
        ids.push(code);
        $div.append(code + "<br />");
    });



});

Calling Python in PHP

If you want to execute your Python script in PHP, it's necessary to do this command in your php script:

exec('your script python.py')

Angular 2.0 router not working on reloading the browser

I had the same problem with using webpack-dev-server. I had to add the devServer option to my webpack.

Solution:

// in webpack
devServer: {
    historyApiFallback: true,
    stats: 'minimal'
}

How to preview git-pull without doing fetch?

You can fetch from a remote repo, see the differences and then pull or merge.

This is an example for a remote repo called origin and a branch called master tracking the remote branch origin/master:

git checkout master                                                  
git fetch                                        
git diff origin/master
git pull --rebase origin master

Reading images in python

Easy way

from IPython.display import Image

Image(filename ="Covid.jpg" size )

Best way to restrict a text field to numbers only?

Javascript is often used on the browser client side to perform simple tasks that would otherwise require a full postback to the server. Many of those simple tasks involve processing text or characters entered into a form element on a web page, and it is often necessary to know the javascript keycode associated with a character. Here is a reference.

Press a key in the text box below to see the corresponding Javascript key code.

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_x000D_
        function restrictCharacters(evt) {_x000D_
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            evt = (evt) ? evt : window.event;_x000D_
            var charCode = (evt.which) ? evt.which : evt.keyCode;_x000D_
            if (((charCode >= '48') && (charCode <= '57')) || (charCode == '44')) {_x000D_
                return true;_x000D_
            }_x000D_
            else {_x000D_
                return false;_x000D_
            }_x000D_
        }
_x000D_
Enter Text:_x000D_
<input type="text" id="number" onkeypress="return restrictCharacters(event);" />
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_x000D_
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Error: Segmentation fault (core dumped)

It's worth trying faulthandler to identify the line or the library that is causing the issue as mentioned here https://stackoverflow.com/a/58825725/2160809 and in the comments by Karuhanga

faulthandler.enable()
// bad code goes here

or

$ python3 -q -X faulthandler
>>> /// bad cod goes here

Is there an advantage to use a Synchronized Method instead of a Synchronized Block?

The only real difference is that a synchronized block can choose which object it synchronizes on. A synchronized method can only use 'this' (or the corresponding Class instance for a synchronized class method). For example, these are semantically equivalent:

synchronized void foo() {
  ...
}

void foo() {
    synchronized (this) {
      ...
    }
}

The latter is more flexible since it can compete for the associated lock of any object, often a member variable. It's also more granular because you could have concurrent code executing before and after the block but still within the method. Of course, you could just as easily use a synchronized method by refactoring the concurrent code into separate non-synchronized methods. Use whichever makes the code more comprehensible.

Where is database .bak file saved from SQL Server Management Studio?

As said by Faiyaz, to get default backup location for the instance, you cannot get it into msdb, but you have to look into Registry. You can get it in T-SQL in using xp_instance_regread stored procedure like this:

EXEC  master.dbo.xp_instance_regread 
      N'HKEY_LOCAL_MACHINE', N'SOFTWARE\Microsoft\\Microsoft SQL Server\MSSQL12.MSSQLSERVER\MSSQLServer',N'BackupDirectory'

The double backslash (\\) is because the spaces into that key name part (Microsoft SQL Server). The "MSSQL12.MSSQLSERVER" part is for default instance name for SQL 2014. You have to adapt to put your own instance name (look into Registry).

Restful API service

If your service is going to be part of you application then you are making it way more complex than it needs to be. Since you have a simple use case of getting some data from a RESTful Web Service, you should look into ResultReceiver and IntentService.

This Service + ResultReceiver pattern works by starting or binding to the service with startService() when you want to do some action. You can specify the operation to perform and pass in your ResultReceiver (the activity) through the extras in the Intent.

In the service you implement onHandleIntent to do the operation that is specified in the Intent. When the operation is completed you use the passed in ResultReceiver to send a message back to the Activity at which point onReceiveResult will be called.

So for example, you want to pull some data from your Web Service.

  1. You create the intent and call startService.
  2. The operation in the service starts and it sends the activity a message saying it started
  3. The activity processes the message and shows a progress.
  4. The service finishes the operation and sends some data back to your activity.
  5. Your activity processes the data and puts in in a list view
  6. The service sends you a message saying that it is done, and it kills itself.
  7. The activity gets the finish message and hides the progress dialog.

I know you mentioned you didn't want a code base but the open source Google I/O 2010 app uses a service in this way I am describing.

Updated to add sample code:

The activity.

public class HomeActivity extends Activity implements MyResultReceiver.Receiver {

    public MyResultReceiver mReceiver;

    public void onCreate(Bundle savedInstanceState) {
        mReceiver = new MyResultReceiver(new Handler());
        mReceiver.setReceiver(this);
        ...
        final Intent intent = new Intent(Intent.ACTION_SYNC, null, this, QueryService.class);
        intent.putExtra("receiver", mReceiver);
        intent.putExtra("command", "query");
        startService(intent);
    }

    public void onPause() {
        mReceiver.setReceiver(null); // clear receiver so no leaks.
    }

    public void onReceiveResult(int resultCode, Bundle resultData) {
        switch (resultCode) {
        case RUNNING:
            //show progress
            break;
        case FINISHED:
            List results = resultData.getParcelableList("results");
            // do something interesting
            // hide progress
            break;
        case ERROR:
            // handle the error;
            break;
    }
}

The Service:

public class QueryService extends IntentService {
    protected void onHandleIntent(Intent intent) {
        final ResultReceiver receiver = intent.getParcelableExtra("receiver");
        String command = intent.getStringExtra("command");
        Bundle b = new Bundle();
        if(command.equals("query") {
            receiver.send(STATUS_RUNNING, Bundle.EMPTY);
            try {
                // get some data or something           
                b.putParcelableArrayList("results", results);
                receiver.send(STATUS_FINISHED, b)
            } catch(Exception e) {
                b.putString(Intent.EXTRA_TEXT, e.toString());
                receiver.send(STATUS_ERROR, b);
            }    
        }
    }
}

ResultReceiver extension - edited about to implement MyResultReceiver.Receiver

public class MyResultReceiver implements ResultReceiver {
    private Receiver mReceiver;

    public MyResultReceiver(Handler handler) {
        super(handler);
    }

    public void setReceiver(Receiver receiver) {
        mReceiver = receiver;
    }

    public interface Receiver {
        public void onReceiveResult(int resultCode, Bundle resultData);
    }

    @Override
    protected void onReceiveResult(int resultCode, Bundle resultData) {
        if (mReceiver != null) {
            mReceiver.onReceiveResult(resultCode, resultData);
        }
    }
}

How do I finish the merge after resolving my merge conflicts?

When there is a conflict during a merge, you have to finish the merge commit manually. It sounds like you've done the first two steps, to edit the files that conflicted and then run git add on them to mark them as resolved. Finally, you need to actually commit the merge with git commit. At that point you will be able to switch branches again.

Set focus on <input> element

Only using Angular Template

<input type="text" #searchText>

<span (click)="searchText.focus()">clear</span>

How to remove old Docker containers

You can use some of the Docker UI applications to remove containers.

Sorry for advertisement, but I always use my own application to do the same things. You can try it if you are looking for a simple application to manage Docker images or containers: https://github.com/alex-agency/AMHub.

This is a Docker UI web application which is running inside a Docker container. For installing it, you only need invoke this command:

docker run -d -p 80:80 -p 8000:8000 -e DOCKER=$(which docker) -v /var/run/docker.sock:/docker.sock alexagency/amhub

PLS-00428: an INTO clause is expected in this SELECT statement

In PLSQL block, columns of select statements must be assigned to variables, which is not the case in SQL statements.

The second BEGIN's SQL statement doesn't have INTO clause and that caused the error.

DECLARE
   PROD_ROW_ID   VARCHAR (10) := NULL;
   VIS_ROW_ID    NUMBER;
   DSC           VARCHAR (512);
BEGIN
   SELECT ROW_ID
     INTO VIS_ROW_ID
     FROM SIEBEL.S_PROD_INT
    WHERE PART_NUM = 'S0146404';

   BEGIN
      SELECT    RTRIM (VIS.SERIAL_NUM)
             || ','
             || RTRIM (PLANID.DESC_TEXT)
             || ','
             || CASE
                   WHEN PLANID.HIGH = 'TEST123'
                   THEN
                      CASE
                         WHEN TO_DATE (PROD.START_DATE) + 30 > SYSDATE
                         THEN
                            'Y'
                         ELSE
                            'N'
                      END
                   ELSE
                      'N'
                END
             || ','
             || 'GB'
             || ','
             || RTRIM (TO_CHAR (PROD.START_DATE, 'YYYY-MM-DD'))
        INTO DSC
        FROM SIEBEL.S_LST_OF_VAL PLANID
             INNER JOIN SIEBEL.S_PROD_INT PROD
                ON PROD.PART_NUM = PLANID.VAL
             INNER JOIN SIEBEL.S_ASSET NETFLIX
                ON PROD.PROD_ID = PROD.ROW_ID
             INNER JOIN SIEBEL.S_ASSET VIS
                ON VIS.PROM_INTEG_ID = PROD.PROM_INTEG_ID
             INNER JOIN SIEBEL.S_PROD_INT VISPROD
                ON VIS.PROD_ID = VISPROD.ROW_ID
       WHERE     PLANID.TYPE = 'Test Plan'
             AND PLANID.ACTIVE_FLG = 'Y'
             AND VISPROD.PART_NUM = VIS_ROW_ID
             AND PROD.STATUS_CD = 'Active'
             AND VIS.SERIAL_NUM IS NOT NULL;
   END;
END;
/

References

http://docs.oracle.com/cd/E11882_01/appdev.112/e25519/static.htm#LNPLS00601 http://docs.oracle.com/cd/B19306_01/appdev.102/b14261/selectinto_statement.htm#CJAJAAIG http://pls-00428.ora-code.com/

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

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

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

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

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

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

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

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

Rename multiple files in a directory in Python

The following code should work. It takes every filename in the current directory, if the filename contains the pattern CHEESE_CHEESE_ then it is renamed. If not nothing is done to the filename.

import os
for fileName in os.listdir("."):
    os.rename(fileName, fileName.replace("CHEESE_CHEESE_", "CHEESE_"))

How to get different colored lines for different plots in a single figure?

Matplot colors your plot with different colors , but incase you wanna put specific colors

    import matplotlib.pyplot as plt
    import numpy as np
            
    x = np.arange(10)
            
    plt.plot(x, x)
    plt.plot(x, 2 * x,color='blue')
    plt.plot(x, 3 * x,color='red')
    plt.plot(x, 4 * x,color='green')
    plt.show()

Convert from MySQL datetime to another format with PHP

If you're looking for a way to normalize a date into MySQL format, use the following

$phpdate = strtotime( $mysqldate );
$mysqldate = date( 'Y-m-d H:i:s', $phpdate );

The line $phpdate = strtotime( $mysqldate ) accepts a string and performs a series of heuristics to turn that string into a unix timestamp.

The line $mysqldate = date( 'Y-m-d H:i:s', $phpdate ) uses that timestamp and PHP's date function to turn that timestamp back into MySQL's standard date format.

(Editor Note: This answer is here because of an original question with confusing wording, and the general Google usefulness this answer provided even if it didnt' directly answer the question that now exists)

How to verify Facebook access token?

Simply request (HTTP GET):

https://graph.facebook.com/USER_ID/access_token=xxxxxxxxxxxxxxxxx

That's it.

Update Row if it Exists Else Insert Logic with Entity Framework

If you know that you're using the same context and not detaching any entities, you can make a generic version like this:

public void InsertOrUpdate<T>(T entity, DbContext db) where T : class
{
    if (db.Entry(entity).State == EntityState.Detached)
        db.Set<T>().Add(entity);

    // If an immediate save is needed, can be slow though
    // if iterating through many entities:
    db.SaveChanges(); 
}

db can of course be a class field, or the method can be made static and an extension, but this is the basics.

How do I base64 encode a string efficiently using Excel VBA?

This code works very fast. It comes from here

Option Explicit

Private Const clOneMask = 16515072          '000000 111111 111111 111111
Private Const clTwoMask = 258048            '111111 000000 111111 111111
Private Const clThreeMask = 4032            '111111 111111 000000 111111
Private Const clFourMask = 63               '111111 111111 111111 000000

Private Const clHighMask = 16711680         '11111111 00000000 00000000
Private Const clMidMask = 65280             '00000000 11111111 00000000
Private Const clLowMask = 255               '00000000 00000000 11111111

Private Const cl2Exp18 = 262144             '2 to the 18th power
Private Const cl2Exp12 = 4096               '2 to the 12th
Private Const cl2Exp6 = 64                  '2 to the 6th
Private Const cl2Exp8 = 256                 '2 to the 8th
Private Const cl2Exp16 = 65536              '2 to the 16th

Public Function Encode64(sString As String) As String

    Dim bTrans(63) As Byte, lPowers8(255) As Long, lPowers16(255) As Long, bOut() As Byte, bIn() As Byte
    Dim lChar As Long, lTrip As Long, iPad As Integer, lLen As Long, lTemp As Long, lPos As Long, lOutSize As Long

    For lTemp = 0 To 63                                 'Fill the translation table.
        Select Case lTemp
            Case 0 To 25
                bTrans(lTemp) = 65 + lTemp              'A - Z
            Case 26 To 51
                bTrans(lTemp) = 71 + lTemp              'a - z
            Case 52 To 61
                bTrans(lTemp) = lTemp - 4               '1 - 0
            Case 62
                bTrans(lTemp) = 43                      'Chr(43) = "+"
            Case 63
                bTrans(lTemp) = 47                      'Chr(47) = "/"
        End Select
    Next lTemp

    For lTemp = 0 To 255                                'Fill the 2^8 and 2^16 lookup tables.
        lPowers8(lTemp) = lTemp * cl2Exp8
        lPowers16(lTemp) = lTemp * cl2Exp16
    Next lTemp

    iPad = Len(sString) Mod 3                           'See if the length is divisible by 3
    If iPad Then                                        'If not, figure out the end pad and resize the input.
        iPad = 3 - iPad
        sString = sString & String(iPad, Chr(0))
    End If

    bIn = StrConv(sString, vbFromUnicode)               'Load the input string.
    lLen = ((UBound(bIn) + 1) \ 3) * 4                  'Length of resulting string.
    lTemp = lLen \ 72                                   'Added space for vbCrLfs.
    lOutSize = ((lTemp * 2) + lLen) - 1                 'Calculate the size of the output buffer.
    ReDim bOut(lOutSize)                                'Make the output buffer.

    lLen = 0                                            'Reusing this one, so reset it.

    For lChar = LBound(bIn) To UBound(bIn) Step 3
        lTrip = lPowers16(bIn(lChar)) + lPowers8(bIn(lChar + 1)) + bIn(lChar + 2)    'Combine the 3 bytes
        lTemp = lTrip And clOneMask                     'Mask for the first 6 bits
        bOut(lPos) = bTrans(lTemp \ cl2Exp18)           'Shift it down to the low 6 bits and get the value
        lTemp = lTrip And clTwoMask                     'Mask for the second set.
        bOut(lPos + 1) = bTrans(lTemp \ cl2Exp12)       'Shift it down and translate.
        lTemp = lTrip And clThreeMask                   'Mask for the third set.
        bOut(lPos + 2) = bTrans(lTemp \ cl2Exp6)        'Shift it down and translate.
        bOut(lPos + 3) = bTrans(lTrip And clFourMask)   'Mask for the low set.
        If lLen = 68 Then                               'Ready for a newline
            bOut(lPos + 4) = 13                         'Chr(13) = vbCr
            bOut(lPos + 5) = 10                         'Chr(10) = vbLf
            lLen = 0                                    'Reset the counter
            lPos = lPos + 6
        Else
            lLen = lLen + 4
            lPos = lPos + 4
        End If
    Next lChar

    If bOut(lOutSize) = 10 Then lOutSize = lOutSize - 2 'Shift the padding chars down if it ends with CrLf.

    If iPad = 1 Then                                    'Add the padding chars if any.
        bOut(lOutSize) = 61                             'Chr(61) = "="
    ElseIf iPad = 2 Then
        bOut(lOutSize) = 61
        bOut(lOutSize - 1) = 61
    End If

    Encode64 = StrConv(bOut, vbUnicode)                 'Convert back to a string and return it.

End Function

Public Function Decode64(sString As String) As String

    Dim bOut() As Byte, bIn() As Byte, bTrans(255) As Byte, lPowers6(63) As Long, lPowers12(63) As Long
    Dim lPowers18(63) As Long, lQuad As Long, iPad As Integer, lChar As Long, lPos As Long, sOut As String
    Dim lTemp As Long

    sString = Replace(sString, vbCr, vbNullString)      'Get rid of the vbCrLfs.  These could be in...
    sString = Replace(sString, vbLf, vbNullString)      'either order.

    lTemp = Len(sString) Mod 4                          'Test for valid input.
    If lTemp Then
        Call Err.Raise(vbObjectError, "MyDecode", "Input string is not valid Base64.")
    End If

    If InStrRev(sString, "==") Then                     'InStrRev is faster when you know it's at the end.
        iPad = 2                                        'Note:  These translate to 0, so you can leave them...
    ElseIf InStrRev(sString, "=") Then                  'in the string and just resize the output.
        iPad = 1
    End If

    For lTemp = 0 To 255                                'Fill the translation table.
        Select Case lTemp
            Case 65 To 90
                bTrans(lTemp) = lTemp - 65              'A - Z
            Case 97 To 122
                bTrans(lTemp) = lTemp - 71              'a - z
            Case 48 To 57
                bTrans(lTemp) = lTemp + 4               '1 - 0
            Case 43
                bTrans(lTemp) = 62                      'Chr(43) = "+"
            Case 47
                bTrans(lTemp) = 63                      'Chr(47) = "/"
        End Select
    Next lTemp

    For lTemp = 0 To 63                                 'Fill the 2^6, 2^12, and 2^18 lookup tables.
        lPowers6(lTemp) = lTemp * cl2Exp6
        lPowers12(lTemp) = lTemp * cl2Exp12
        lPowers18(lTemp) = lTemp * cl2Exp18
    Next lTemp

    bIn = StrConv(sString, vbFromUnicode)               'Load the input byte array.
    ReDim bOut((((UBound(bIn) + 1) \ 4) * 3) - 1)       'Prepare the output buffer.

    For lChar = 0 To UBound(bIn) Step 4
        lQuad = lPowers18(bTrans(bIn(lChar))) + lPowers12(bTrans(bIn(lChar + 1))) + _
                lPowers6(bTrans(bIn(lChar + 2))) + bTrans(bIn(lChar + 3))           'Rebuild the bits.
        lTemp = lQuad And clHighMask                    'Mask for the first byte
        bOut(lPos) = lTemp \ cl2Exp16                   'Shift it down
        lTemp = lQuad And clMidMask                     'Mask for the second byte
        bOut(lPos + 1) = lTemp \ cl2Exp8                'Shift it down
        bOut(lPos + 2) = lQuad And clLowMask            'Mask for the third byte
        lPos = lPos + 3
    Next lChar

    sOut = StrConv(bOut, vbUnicode)                     'Convert back to a string.
    If iPad Then sOut = Left$(sOut, Len(sOut) - iPad)   'Chop off any extra bytes.
    Decode64 = sOut

End Function

How to print a groupby object

Also, other simple alternative could be:

gb = df.groupby("A")
gb.count() # or,
gb.get_group(your_key)

IOError: [Errno 22] invalid mode ('r') or filename: 'c:\\Python27\test.txt'

\t in a string marks an escape sequence for a tab character. For a literal \, use \\.

Fatal error: Out of memory, but I do have plenty of memory (PHP)

Could be an issue with MySQL and the number of open connections, hence why it sorts itself out when you restart every few days. Are they auto closing on script shutdown?

CASE statement in SQLite query

The syntax is wrong in this clause (and similar ones)

    CASE lkey WHEN lkey > 5 THEN
        lkey + 2
    ELSE
        lkey
    END

It's either

    CASE WHEN [condition] THEN [expression] ELSE [expression] END

or

    CASE [expression] WHEN [value] THEN [expression] ELSE [expression] END

So in your case it would read:

    CASE WHEN lkey > 5 THEN
        lkey + 2
    ELSE
        lkey
    END

Check out the documentation (The CASE expression):

http://www.sqlite.org/lang_expr.html

How to check if a row exists in MySQL? (i.e. check if an email exists in MySQL)

There are multiple ways to check if a value exists in the database. Let me demonstrate how this can be done properly with PDO and mysqli.

PDO

PDO is the simpler option. To find out whether a value exists in the database you can use prepared statement and fetchColumn(). There is no need to fetch any data so we will only fetch 1 if the value exists.

<?php

// Connection code. 
$options = [
    \PDO::ATTR_ERRMODE            => \PDO::ERRMODE_EXCEPTION,
    \PDO::ATTR_EMULATE_PREPARES   => false,
];
$pdo = new \PDO('mysql:host=localhost;port=3306;dbname=test;charset=utf8mb4', 'testuser', 'password', $options);

// Prepared statement
$stmt = $pdo->prepare('SELECT 1 FROM tblUser WHERE email=?');
$stmt->execute([$_POST['email']]);
$exists = $stmt->fetchColumn(); // either 1 or null

if ($exists) {
    echo 'Email exists in the database.';
} else {
    // email doesn't exist yet
}

For more examples see: How to check if email exists in the database?

MySQLi

As always mysqli is a little more cumbersome and more restricted, but we can follow a similar approach with prepared statement.

<?php

// Connection code
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);
$mysqli = new \mysqli('localhost', 'testuser', 'password', 'test');
$mysqli->set_charset('utf8mb4');

// Prepared statement
$stmt = $mysqli->prepare('SELECT 1 FROM tblUser WHERE email=?');
$stmt->bind_param('s', $_POST['email']);
$stmt->execute();
$exists = (bool) $stmt->get_result()->fetch_row(); // Get the first row from result and cast to boolean

if ($exists) {
    echo 'Email exists in the database.';
} else {
    // email doesn't exist yet
}

Instead of casting the result row(which might not even exist) to boolean, you can also fetch COUNT(1) and read the first item from the first row using fetch_row()[0]

For more examples see: How to check whether a value exists in a database using mysqli prepared statements

Minor remarks

  • If someone suggests you to use mysqli_num_rows(), don't listen to them. This is a very bad approach and could lead to performance issues if misused.
  • Don't use real_escape_string(). This is not meant to be used as a protection against SQL injection. If you use prepared statements correctly you don't need to worry about any escaping.
  • If you want to check if a row exists in the database before you try to insert a new one, then it is better not to use this approach. It is better to create a unique key in the database and let it throw an exception if a duplicate value exists.

firefox proxy settings via command line

for the latest firefox you must change

cd *.default

to

cd *.default*

adb server version doesn't match this client

I simply closed the htc sync application completely and tried again. It worked as it was supposed to.

how to select first N rows from a table in T-SQL?

You can use Microsoft's row_number() function to decide which rows to return. That means that you aren't limited to just the top X results, you can take pages.

SELECT * 
FROM (SELECT row_number() over (order by UserID) AS line_no, * 
      FROM dbo.User) as users
WHERE users.line_no < 10
OR users.line_no BETWEEN 34 and 67

You have to nest the original query though, because otherwise you'll get an error message telling you that you can't do what you want to in the way you probably should be able to in an ideal world.

Msg 4108, Level 15, State 1, Line 3
Windowed functions can only appear in the SELECT or ORDER BY clauses.

How to .gitignore all files/folder in a folder, but not the folder itself?

You can't commit empty folders in git. If you want it to show up, you need to put something in it, even just an empty file.

For example, add an empty file called .gitkeep to the folder you want to keep, then in your .gitignore file write:

# exclude everything
somefolder/*

# exception to the rule
!somefolder/.gitkeep 

Commit your .gitignore and .gitkeep files and this should resolve your issue.

How to list all the files in android phone by using adb shell?

just to add the full command:

adb shell ls -R | grep filename

this is actually a pretty fast lookup on Android

Open Bootstrap Modal from code-behind

How about doing it like this:

1) show popup with form

2) submit form using AJAX

3) in AJAX server side code, render response that will either:

  • show popup with form with validations or just a message
  • close the popup (and maybe redirect you to new page)

ORDER BY date and time BEFORE GROUP BY name in mysql

I had a different variation on this question where I only had a single DATETIME field and needed a limit after a group by or distinct after sorting descending based on the datetime field, but this is what helped me:

select distinct (column) from
(select column from database.table
order by date_column DESC) as hist limit 10

In this instance with the split fields, if you can sort on a concat, then you might be able to get away with something like:

select name,date,time from
(select name from table order by concat(date,' ',time) ASC)
as sorted

Then if you wanted to limit you would simply add your limit statement to the end:

select name,date,time from
(select name from table order by concat(date,' ',time) ASC)
as sorted limit 10

Convert byte[] to char[]

System.Text.Encoding.ChooseYourEncoding.GetString(bytes).ToCharArray();

Substitute the right encoding above: e.g.

System.Text.Encoding.UTF8.GetString(bytes).ToCharArray();

How to generate a random number between a and b in Ruby?

See this answer: there is in Ruby 1.9.2, but not in earlier versions. Personally I think rand(8) + 3 is fine, but if you're interested check out the Random class described in the link.

MongoDB: Combine data from multiple collections into one..how?

Doing unions in MongoDB in a 'SQL UNION' fashion is possible using aggregations along with lookups, in a single query. Here is an example I have tested that works with MongoDB 4.0:

// Create employees data for testing the union.
db.getCollection('employees').insert({ name: "John", type: "employee", department: "sales" });
db.getCollection('employees').insert({ name: "Martha", type: "employee", department: "accounting" });
db.getCollection('employees').insert({ name: "Amy", type: "employee", department: "warehouse" });
db.getCollection('employees').insert({ name: "Mike", type: "employee", department: "warehouse"  });

// Create freelancers data for testing the union.
db.getCollection('freelancers').insert({ name: "Stephany", type: "freelancer", department: "accounting" });
db.getCollection('freelancers').insert({ name: "Martin", type: "freelancer", department: "sales" });
db.getCollection('freelancers').insert({ name: "Doug", type: "freelancer", department: "warehouse"  });
db.getCollection('freelancers').insert({ name: "Brenda", type: "freelancer", department: "sales"  });

// Here we do a union of the employees and freelancers using a single aggregation query.
db.getCollection('freelancers').aggregate( // 1. Use any collection containing at least one document.
  [
    { $limit: 1 }, // 2. Keep only one document of the collection.
    { $project: { _id: '$$REMOVE' } }, // 3. Remove everything from the document.

    // 4. Lookup collections to union together.
    { $lookup: { from: 'employees', pipeline: [{ $match: { department: 'sales' } }], as: 'employees' } },
    { $lookup: { from: 'freelancers', pipeline: [{ $match: { department: 'sales' } }], as: 'freelancers' } },

    // 5. Union the collections together with a projection.
    { $project: { union: { $concatArrays: ["$employees", "$freelancers"] } } },

    // 6. Unwind and replace root so you end up with a result set.
    { $unwind: '$union' },
    { $replaceRoot: { newRoot: '$union' } }
  ]);

Here is the explanation of how it works:

  1. Instantiate an aggregate out of any collection of your database that has at least one document in it. If you can't guarantee any collection of your database will not be empty, you can workaround this issue by creating in your database some sort of 'dummy' collection containing a single empty document in it that will be there specifically for doing union queries.

  2. Make the first stage of your pipeline to be { $limit: 1 }. This will strip all the documents of the collection except the first one.

  3. Strip all the fields of the remaining document by using a $project stage:

    { $project: { _id: '$$REMOVE' } }
    
  4. Your aggregate now contains a single, empty document. It's time to add lookups for each collection you want to union together. You may use the pipeline field to do some specific filtering, or leave localField and foreignField as null to match the whole collection.

    { $lookup: { from: 'collectionToUnion1', pipeline: [...], as: 'Collection1' } },
    { $lookup: { from: 'collectionToUnion2', pipeline: [...], as: 'Collection2' } },
    { $lookup: { from: 'collectionToUnion3', pipeline: [...], as: 'Collection3' } }
    
  5. You now have an aggregate containing a single document that contains 3 arrays like this:

    {
        Collection1: [...],
        Collection2: [...],
        Collection3: [...]
    }
    

    You can then merge them together into a single array using a $project stage along with the $concatArrays aggregation operator:

    {
      "$project" :
      {
        "Union" : { $concatArrays: ["$Collection1", "$Collection2", "$Collection3"] }
      }
    }
    
  6. You now have an aggregate containing a single document, into which is located an array that contains your union of collections. What remains to be done is to add an $unwind and a $replaceRoot stage to split your array into separate documents:

    { $unwind: "$Union" },
    { $replaceRoot: { newRoot: "$Union" } }
    
  7. Voilà. You now have a result set containing the collections you wanted to union together. You can then add more stages to filter it further, sort it, apply skip() and limit(). Pretty much anything you want.

Java equivalent to Explode and Implode(PHP)

if you are talking about in the reference of String Class. so you can use

subString/split

for Explode & use String

concate

for Implode.

EF LINQ include multiple and nested entities

this is from my project

 var saleHeadBranch = await _context.SaleHeadBranch
 .Include(d => d.SaleDetailBranch)
 .ThenInclude(d => d.Item)
 .Where(d => d.BranchId == loginTkn.branchId)
 .FirstOrDefaultAsync(d => d.Id == id);

How to end a session in ExpressJS

Never mind, it's req.session.destroy();

Format a message using MessageFormat.format() in Java

Using an apostrophe (Unicode: \u2019) instead of a single quote ' fixed the issue without doubling the \'.

How do I make a checkbox required on an ASP.NET form?

javascript function for client side validation (using jQuery)...

function CheckBoxRequired_ClientValidate(sender, e)
{
    e.IsValid = jQuery(".AcceptedAgreement input:checkbox").is(':checked');
}

code-behind for server side validation...

protected void CheckBoxRequired_ServerValidate(object sender, ServerValidateEventArgs e)
{
    e.IsValid = MyCheckBox.Checked;
}

ASP.Net code for the checkbox & validator...

<asp:CheckBox runat="server" ID="MyCheckBox" CssClass="AcceptedAgreement" />
<asp:CustomValidator runat="server" ID="CheckBoxRequired" EnableClientScript="true"
    OnServerValidate="CheckBoxRequired_ServerValidate"
    ClientValidationFunction="CheckBoxRequired_ClientValidate">You must select this box to proceed.</asp:CustomValidator>

and finally, in your postback - whether from a button or whatever...

if (Page.IsValid)
{
    // your code here...
}

How to add link to flash banner

@Michiel is correct to create a button but the code for ActionScript 3 it is a little different - where movieClipName is the name of your 'button'.

movieClipName.addEventListener(MouseEvent.CLICK, callLink);
function callLink:void {
  var url:String = "http://site";
  var request:URLRequest = new URLRequest(url);
  try {
    navigateToURL(request, '_blank');
  } catch (e:Error) {
    trace("Error occurred!");
  }
}

source: http://scriptplayground.com/tutorials/as/getURL-in-Actionscript-3/

Repeat command automatically in Linux

A concise solution, which is particularly useful if you want to run the command repeatedly until it fails, and lets you see all output.

while ls -l; do
    sleep 5
done

how to toggle (hide/show) a table onClick of <a> tag in java script

visibility property makes the element visible or invisible.

function showTable(){
    document.getElementById('table').style.visibility = "visible";
}
function hideTable(){
    document.getElementById('table').style.visibility = "hidden";
}

Android, How to read QR code in my application?

Easy QR Code Library

A simple Android Easy QR Code Library. It is very easy to use, to use this library follow these steps.

For Gradle:

Step 1. Add it in your root build.gradle at the end of repositories:

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
    }
}

Step 2. Add the dependency:

dependencies {
        compile 'com.github.mrasif:easyqrlibrary:v1.0.0'
}

For Maven:

Step 1. Add the JitPack repository to your build file:

<repositories>
    <repository>
        <id>jitpack.io</id>
        <url>https://jitpack.io</url>
    </repository>
</repositories>

Step 2. Add the dependency:

<dependency>
    <groupId>com.github.mrasif</groupId>
    <artifactId>easyqrlibrary</artifactId>
    <version>v1.0.0</version>
</dependency>

For SBT:

Step 1. Add the JitPack repository to your build.sbt file:

resolvers += "jitpack" at "https://jitpack.io"

Step 2. Add the dependency:

libraryDependencies += "com.github.mrasif" % "easyqrlibrary" % "v1.0.0"

For Leiningen:

Step 1. Add it in your project.clj at the end of repositories:

:repositories [["jitpack" "https://jitpack.io"]]

Step 2. Add the dependency:

:dependencies [[com.github.mrasif/easyqrlibrary "v1.0.0"]]

Add this in your layout xml file:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="20dp"
    tools:context=".MainActivity"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tvData"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:text="No QR Data"/>
    <Button
        android:id="@+id/btnQRScan"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="QR Scan"/>

</LinearLayout>

Add this in your activity java files:

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    TextView tvData;
    Button btnQRScan;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tvData=findViewById(R.id.tvData);
        btnQRScan=findViewById(R.id.btnQRScan);

        btnQRScan.setOnClickListener(this);
    }

    @Override
    public void onClick(View view){
        switch (view.getId()){
            case R.id.btnQRScan: {
                Intent intent=new Intent(MainActivity.this, QRScanner.class);
                startActivityForResult(intent, EasyQR.QR_SCANNER_REQUEST);
            } break;
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch (requestCode){
            case EasyQR.QR_SCANNER_REQUEST: {
                if (resultCode==RESULT_OK){
                    tvData.setText(data.getStringExtra(EasyQR.DATA));
                }
            } break;
        }
    }
}

For customized scanner screen just add these lines when you start the scanner Activity.

Intent intent=new Intent(MainActivity.this, QRScanner.class);
intent.putExtra(EasyQR.IS_TOOLBAR_SHOW,true);
intent.putExtra(EasyQR.TOOLBAR_DRAWABLE_ID,R.drawable.ic_audiotrack_dark);
intent.putExtra(EasyQR.TOOLBAR_TEXT,"My QR");
intent.putExtra(EasyQR.TOOLBAR_BACKGROUND_COLOR,"#0588EE");
intent.putExtra(EasyQR.TOOLBAR_TEXT_COLOR,"#FFFFFF");
intent.putExtra(EasyQR.BACKGROUND_COLOR,"#000000");
intent.putExtra(EasyQR.CAMERA_MARGIN_LEFT,50);
intent.putExtra(EasyQR.CAMERA_MARGIN_TOP,50);
intent.putExtra(EasyQR.CAMERA_MARGIN_RIGHT,50);
intent.putExtra(EasyQR.CAMERA_MARGIN_BOTTOM,50);
startActivityForResult(intent, EasyQR.QR_SCANNER_REQUEST);

You are done. Ref. Link: https://mrasif.github.io/easyqrlibrary

node.js require all files in a folder?

I know this question is 5+ years old, and the given answers are good, but I wanted something a bit more powerful for express, so i created the express-map2 package for npm. I was going to name it simply express-map, however the people at yahoo already have a package with that name, so i had to rename my package.

1. basic usage:

app.js (or whatever you call it)

var app = require('express'); // 1. include express

app.set('controllers',__dirname+'/controllers/');// 2. set path to your controllers.

require('express-map2')(app); // 3. patch map() into express

app.map({
    'GET /':'test',
    'GET /foo':'middleware.foo,test',
    'GET /bar':'middleware.bar,test'// seperate your handlers with a comma. 
});

controller usage:

//single function
module.exports = function(req,res){

};

//export an object with multiple functions.
module.exports = {

    foo: function(req,res){

    },

    bar: function(req,res){

    }

};

2. advanced usage, with prefixes:

app.map('/api/v1/books',{
    'GET /': 'books.list', // GET /api/v1/books
    'GET /:id': 'books.loadOne', // GET /api/v1/books/5
    'DELETE /:id': 'books.delete', // DELETE /api/v1/books/5
    'PUT /:id': 'books.update', // PUT /api/v1/books/5
    'POST /': 'books.create' // POST /api/v1/books
});

As you can see, this saves a ton of time and makes the routing of your application dead simple to write, maintain, and understand. it supports all of the http verbs that express supports, as well as the special .all() method.

Why is textarea filled with mysterious white spaces?

If you still like to use indentation, do it after opening the <?php tag, like so:

<textarea style="width:350px; height:80px;" cols="42" rows="5" name="sitelink"><?php // <--- newline
    if($siteLink_val) echo $siteLink_val; // <--- indented, newline
?></textarea>

PHPMailer AddAddress()

Some great answers above, using that info here is what I did today to solve the same issue:

$to_array = explode(',', $to);
foreach($to_array as $address)
{
    $mail->addAddress($address, 'Web Enquiry');
}

Getting a timestamp for today at midnight?

$timestamp = strtotime('today midnight');

is the same as

$timestamp = strtotime('today');

and it's a little less work on your server.

Converting double to string

Using Double.toString(), if the number is too small or too large, you will get a scientific notation like this: 3.4875546345347673E-6. There are several ways to have more control of output string format.

double num = 0.000074635638;
// use Double.toString()
System.out.println(Double.toString(num));
// result: 7.4635638E-5

// use String.format
System.out.println(String.format ("%f", num));
// result: 0.000075
System.out.println(String.format ("%.9f", num));
// result: 0.000074636

// use DecimalFormat
DecimalFormat decimalFormat = new DecimalFormat("#,##0.000000");
String numberAsString = decimalFormat.format(num);
System.out.println(numberAsString);
// result: 0.000075

Use String.format() will be the best convenient way.

awk - concatenate two string variable and assign to a third

Could use sprintf to accomplish this:

awk '{str = sprintf("%s %s", $1, $2)} END {print str}' file

How to "set a breakpoint in malloc_error_break to debug"

I solve it by close safari inspector. Refer to my post. I also found sound sometimes when I run my app for testing, then I open safari with auto inspector on, after this, I do some action in my app then this issue triggered.

enter image description here

How do I put my website's logo to be the icon image in browser tabs?

  1. ADD THIS
**<HEAD>**

  < link rel="icon" href="directory/image.png">

Then run and enjoy it

How to sum the values of one column of a dataframe in spark/scala

If you want to sum all values of one column, it's more efficient to use DataFrame's internal RDD and reduce.

import sqlContext.implicits._
import org.apache.spark.sql.functions._

val df = sc.parallelize(Array(10,2,3,4)).toDF("steps")
df.select(col("steps")).rdd.map(_(0).asInstanceOf[Int]).reduce(_+_)

//res1 Int = 19

Checking if jquery is loaded using Javascript

A quick way is to run a jQuery command in the developer console. On any browser hit F12 and try to access any of the element .

 $("#sideTab2").css("background-color", "yellow");

enter image description here

Unable to connect with remote debugger

in my case it also need to install it's npm package

so

npm install react-native-debugger -g

struct.error: unpack requires a string argument of length 4

By default, on many platforms the short will be aligned to an offset at a multiple of 2, so there will be a padding byte added after the char.

To disable this, use: struct.unpack("=BH", data). This will use standard alignment, which doesn't add padding:

>>> struct.calcsize('=BH')
3

The = character will use native byte ordering. You can also use < or > instead of = to force little-endian or big-endian byte ordering, respectively.

Use async await with Array.map

A solution using modern-async's map():

import { map } from 'modern-async'

...
const result = await map(myArray, async (v) => {
    ...
})

The advantage of using that library is that you can control the concurrency using mapLimit() or mapSeries().

PHP string concatenation

Just use . for concatenating. And you missed out the $personCount increment!

while ($personCount < 10) {
    $result .= $personCount . ' people';
    $personCount++;
}

echo $result;

jQuery, simple polling example

Here's a helpful article on long polling (long-held HTTP request) using jQuery. A code snippet derived from this article:

(function poll() {
    setTimeout(function() {
        $.ajax({
            url: "/server/api/function",
            type: "GET",
            success: function(data) {
                console.log("polling");
            },
            dataType: "json",
            complete: poll,
            timeout: 2000
        })
    }, 5000);
})();

This will make the next request only after the ajax request has completed.

A variation on the above that will execute immediately the first time it is called before honouring the wait/timeout interval.

(function poll() {
    $.ajax({
        url: "/server/api/function",
        type: "GET",
        success: function(data) {
            console.log("polling");
        },
        dataType: "json",
        complete: setTimeout(function() {poll()}, 5000),
        timeout: 2000
    })
})();

Where are SQL Server connection attempts logged?

If you'd like to track only failed logins, you can use the SQL Server Audit feature (available in SQL Server 2008 and above). You will need to add the SQL server instance you want to audit, and check the failed login operation to audit.

Note: tracking failed logins via SQL Server Audit has its disadvantages. For example - it doesn't provide the names of client applications used.

If you want to audit a client application name along with each failed login, you can use an Extended Events session.

To get you started, I recommend reading this article: http://www.sqlshack.com/using-extended-events-review-sql-server-failed-logins/

inherit from two classes in C#

Do you mean you want Class C to be the base class for A & B in that case.

public abstract class C
{
    public abstract void Method1();

    public abstract void Method2();
}

public class A : C
{
    public override void Method1()
    {
        throw new NotImplementedException();
    }

    public override void Method2()
    {
        throw new NotImplementedException();
    }
}


public class B : C
{
    public override void Method1()
    {
        throw new NotImplementedException();
    }

    public override void Method2()
    {
        throw new NotImplementedException();
    }
}

Check if something is (not) in a list in Python

The bug is probably somewhere else in your code, because it should work fine:

>>> 3 not in [2, 3, 4]
False
>>> 3 not in [4, 5, 6]
True

Or with tuples:

>>> (2, 3) not in [(2, 3), (5, 6), (9, 1)]
False
>>> (2, 3) not in [(2, 7), (7, 3), "hi"]
True

When to use @QueryParam vs @PathParam

The reason is actually very simple. When using a query parameter you can take in characters such as "/" and your client does not need to html encode them. There are other reasons but that is a simple example. As for when to use a path variable. I would say whenever you are dealing with ids or if the path variable is a direction for a query.

Escaping Strings in JavaScript

You can also use this

_x000D_
_x000D_
let str = "hello single ' double \" and slash \\ yippie";

let escapeStr = escape(str);
document.write("<b>str : </b>"+str);
document.write("<br/><b>escapeStr : </b>"+escapeStr);
document.write("<br/><b>unEscapeStr : </b> "+unescape(escapeStr));
_x000D_
_x000D_
_x000D_

What's the difference between REST & RESTful

A "REST service" and a "RESTful service" are one and the same.

A RESTful system is any system that follows the REST conventions as defined in the original document that created the idea of RESTful networked applications.

It's worth noting there are varying levels of RESTfulness. Overall, REST is a style, not a standard, so there is room for interpretation based on needs. one example is hierarchical resource URLs (e.g. /things/ID/relatedthings) vs flat URLs (e.g. /things/ID and /relatedthings?thing=ID)

How to avoid "Permission denied" when using pip with virtualenv

I didn't create my virtualenv using sudo. So Sebastian's answer didn't apply to me. My project is called utils. I checked utils directory and saw this:

-rw-r--r--   1 macuser  staff   983  6 Jan 15:17 README.md
drwxr-xr-x   6 root     staff   204  6 Jan 14:36 utils.egg-info
-rw-r--r--   1 macuser  staff    31  6 Jan 15:09 requirements.txt

As you can see, utils.egg-info is owned by root not macuser. That is why it was giving me permission denied error. I also had to remove /Users/macuser/.virtualenvs/armoury/lib/python2.7/site-packages/utils.egg-link as it was created by root as well. I did pip install -e . again after removing those, and it worked.

django MultiValueDictKeyError error, how do I deal with it

You get that because you're trying to get a key from a dictionary when it's not there. You need to test if it is in there first.

try:

is_private = 'is_private' in request.POST

or

is_private = 'is_private' in request.POST and request.POST['is_private']

depending on the values you're using.

What exactly does Perl's "bless" do?

bless associates a reference with a package.

It doesn't matter what the reference is to, it can be to a hash (most common case), to an array (not so common), to a scalar (usually this indicates an inside-out object), to a regular expression, subroutine or TYPEGLOB (see the book Object Oriented Perl: A Comprehensive Guide to Concepts and Programming Techniques by Damian Conway for useful examples) or even a reference to a file or directory handle (least common case).

The effect bless-ing has is that it allows you to apply special syntax to the blessed reference.

For example, if a blessed reference is stored in $obj (associated by bless with package "Class"), then $obj->foo(@args) will call a subroutine foo and pass as first argument the reference $obj followed by the rest of the arguments (@args). The subroutine should be defined in package "Class". If there is no subroutine foo in package "Class", a list of other packages (taken form the array @ISA in the package "Class") will be searched and the first subroutine foo found will be called.

Change date format in a Java string

SimpleDateFormat dt1 = new SimpleDateFormat("yyyy-mm-dd");

Oracle Trigger ORA-04098: trigger is invalid and failed re-validation

Cause: A trigger was attempted to be retrieved for execution and was found to be invalid. This also means that compilation/authorization failed for the trigger.

Action: Options are to resolve the compilation/authorization errors, disable the trigger, or drop the trigger.

Syntax

ALTER TRIGGER trigger Name DISABLE;

ALTER TRIGGER trigger_Name ENABLE;

Can I remove the URL from my print css, so the web address doesn't print?

Now we can do this with:

<style type="text/css" media="print">
@page {
    size: auto;   /* auto is the initial value */
    margin: 0;  /* this affects the margin in the printer settings */
}
</style>

Source: https://stackoverflow.com/a/14975912/1760939

How do I create a unique ID in Java?

There are three way to generate unique id in java.

1) the UUID class provides a simple means for generating unique ids.

 UUID id = UUID.randomUUID();
 System.out.println(id);

2) SecureRandom and MessageDigest

//initialization of the application
 SecureRandom prng = SecureRandom.getInstance("SHA1PRNG");

//generate a random number
 String randomNum = new Integer(prng.nextInt()).toString();

//get its digest
 MessageDigest sha = MessageDigest.getInstance("SHA-1");
 byte[] result =  sha.digest(randomNum.getBytes());

System.out.println("Random number: " + randomNum);
System.out.println("Message digest: " + new String(result));

3) using a java.rmi.server.UID

UID userId = new UID();
System.out.println("userId: " + userId);

How to handle back button in activity

This helped me ..

@Override
public void onBackPressed() {
    startActivity(new Intent(currentActivity.this, LastActivity.class));
    finish();
}

OR????? even you can use this for drawer toggle also

@Override
public void onBackPressed() {
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    if (drawer.isDrawerOpen(GravityCompat.START)) {
        drawer.closeDrawer(GravityCompat.START);
    } else {
        super.onBackPressed();
    }
        startActivity(new Intent(currentActivity.this, LastActivity.class));
    finish();

}

I hope this would help you.. :)

LINQ query to select top five

[Offering a somewhat more descriptive answer than the answer provided by @Ajni.]

This can also be achieved using LINQ fluent syntax:

var list = ctn.Items
    .Where(t=> t.DeliverySelection == true && t.Delivery.SentForDelivery == null)
    .OrderBy(t => t.Delivery.SubmissionDate)
    .Take(5);

Note that each method (Where, OrderBy, Take) that appears in this LINQ statement takes a lambda expression as an argument. Also note that the documentation for Enumerable.Take begins with:

Returns a specified number of contiguous elements from the start of a sequence.

How to parse a CSV file in Bash?

From the man page:

-d delim The first character of delim is used to terminate the input line, rather than newline.

You are using -d, which will terminate the input line on the comma. It will not read the rest of the line. That's why $y is empty.

Nested select statement in SQL Server

The answer provided by Joe Stefanelli is already correct.

SELECT name FROM (SELECT name FROM agentinformation) as a  

We need to make an alias of the subquery because a query needs a table object which we will get from making an alias for the subquery. Conceptually, the subquery results are substituted into the outer query. As we need a table object in the outer query, we need to make an alias of the inner query.

Statements that include a subquery usually take one of these forms:

  • WHERE expression [NOT] IN (subquery)
  • WHERE expression comparison_operator [ANY | ALL] (subquery)
  • WHERE [NOT] EXISTS (subquery)

Check for more subquery rules and subquery types.

More examples of Nested Subqueries.

  1. IN / NOT IN – This operator takes the output of the inner query after the inner query gets executed which can be zero or more values and sends it to the outer query. The outer query then fetches all the matching [IN operator] or non matching [NOT IN operator] rows.

  2. ANY – [>ANY or ANY operator takes the list of values produced by the inner query and fetches all the values which are greater than the minimum value of the list. The

e.g. >ANY(100,200,300), the ANY operator will fetch all the values greater than 100.

  1. ALL – [>ALL or ALL operator takes the list of values produced by the inner query and fetches all the values which are greater than the maximum of the list. The

e.g. >ALL(100,200,300), the ALL operator will fetch all the values greater than 300.

  1. EXISTS – The EXISTS keyword produces a Boolean value [TRUE/FALSE]. This EXISTS checks the existence of the rows returned by the sub query.

How to open standard Google Map application from my application?

Check this page from google :

http://developer.android.com/guide/appendix/g-app-intents.html

You can use a URI of the form

geo:latitude,longitude

to open Google map viewer and point it to a location.

How to perform Unwind segue programmatically?

SWIFT 4:

1. Create an @IBAction with segue inside controller you want to unwind to:

    @IBAction func unwindToVC(segue: UIStoryboardSegue) {

    }

2. In the storyboard, from the controller you want to segue (unwind) from ctrl+drag from the controller sign to exit sign and choose method you created earlier:

enter image description here

3. Now you can notice that in document outline you have new line with title "Unwind segue....". Now you should click on this line and open attribute inspector to set identifier (in my case unwindSegueIdentifier).

enter image description here

4. You're almost done! Now you need to open view controller you wish to unwind from and create some method that will perform segue. For example you can add button, connect it with code with @IBAction, after that inside this IBAction add perfromSegue(withIdentifier:sender:) method:

     @IBAction func unwindToSomeVCWithSegue(_ sender: UIButton) {
         performSegue(withIdentifier: "unwindSegueIdentifier", sender: nil)
     }

So that is all you have to do!

How to copy files from 'assets' folder to sdcard?

Here is a cleaned up version for current Android devices, functional method design so that you can copy it to an AssetsHelper class e.g ;)

/**
 * 
 * Info: prior to Android 2.3, any compressed asset file with an
 * uncompressed size of over 1 MB cannot be read from the APK. So this
 * should only be used if the device has android 2.3 or later running!
 * 
 * @param c
 * @param targetFolder
 *            e.g. {@link Environment#getExternalStorageDirectory()}
 * @throws Exception
 */
@TargetApi(Build.VERSION_CODES.GINGERBREAD)
public static boolean copyAssets(AssetManager assetManager,
        File targetFolder) throws Exception {
    Log.i(LOG_TAG, "Copying files from assets to folder " + targetFolder);
    return copyAssets(assetManager, "", targetFolder);
}

/**
 * The files will be copied at the location targetFolder+path so if you
 * enter path="abc" and targetfolder="sdcard" the files will be located in
 * "sdcard/abc"
 * 
 * @param assetManager
 * @param path
 * @param targetFolder
 * @return
 * @throws Exception
 */
public static boolean copyAssets(AssetManager assetManager, String path,
        File targetFolder) throws Exception {
    Log.i(LOG_TAG, "Copying " + path + " to " + targetFolder);
    String sources[] = assetManager.list(path);
    if (sources.length == 0) { // its not a folder, so its a file:
        copyAssetFileToFolder(assetManager, path, targetFolder);
    } else { // its a folder:
        if (path.startsWith("images") || path.startsWith("sounds")
                || path.startsWith("webkit")) {
            Log.i(LOG_TAG, "  > Skipping " + path);
            return false;
        }
        File targetDir = new File(targetFolder, path);
        targetDir.mkdirs();
        for (String source : sources) {
            String fullSourcePath = path.equals("") ? source : (path
                    + File.separator + source);
            copyAssets(assetManager, fullSourcePath, targetFolder);
        }
    }
    return true;
}

private static void copyAssetFileToFolder(AssetManager assetManager,
        String fullAssetPath, File targetBasePath) throws IOException {
    InputStream in = assetManager.open(fullAssetPath);
    OutputStream out = new FileOutputStream(new File(targetBasePath,
            fullAssetPath));
    byte[] buffer = new byte[16 * 1024];
    int read;
    while ((read = in.read(buffer)) != -1) {
        out.write(buffer, 0, read);
    }
    in.close();
    out.flush();
    out.close();
}

How to add an extra column to a NumPy array

I think a more straightforward solution and faster to boot is to do the following:

import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a

And timings:

In [23]: N = 10

In [24]: a = np.random.rand(N,N)

In [25]: %timeit b = np.hstack((a,np.zeros((a.shape[0],1))))
10000 loops, best of 3: 19.6 us per loop

In [27]: %timeit b = np.zeros((a.shape[0],a.shape[1]+1)); b[:,:-1] = a
100000 loops, best of 3: 5.62 us per loop

Installing tensorflow with anaconda in windows

I use windows 10, Anaconda and python 2. A combination of mentioned solutions worked for me:

Once you installed tensorflow using:

C:\Users\Laleh>conda create -n tensorflow python=3.5 # use your python version

C:\Users\Laleh>activate tensorflow

(tensorflow) C:\Users\Laleh>conda install -c conda-forge tensorflow

Then I realized tensorflow can not be imported in jupyter notebook, although it can work in commad windows. To solve this issue first I checked:

jupyter kernelspec list

I removeed the Jupyter kernelspec, useing:

jupyter kernelspec remove python2

Now, the jupyter kernelspec list is pointing to the correct kernel. Again, I activate tensorflow and installed notebook in its environment:

C:\Users\Laleh>activate tensorflow

(tensorflow)C:> conda install notebook

Also if you want to use other libraries such as matplotlib, they should be installed separately in tensorflow environment

(tensorflow)C:> conda install -c conda-forge matplotlib

Now everything works fine for me.

How to set selected item of Spinner by value, not by position?

Suppose you need to fill the spinner from the string-array from the resource, and you want to keep selected the value from server. So, this is one way to set selected a value from server in the spinner.

pincodeSpinner.setSelection(resources.getStringArray(R.array.pincodes).indexOf(javaObject.pincode))

Hope it helps! P.S. the code is in Kotlin!

Function of Project > Clean in Eclipse

I also faced the same issue with Eclipse when I ran the clean build with Maven, but there is a simple solution for this issue. We just need to run Maven update and then build or direct run the application. I hope it will solve the problem.

How to check if a symlink exists

-L returns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).

According to the GNU manpage, -h is identical to -L, but according to the BSD manpage, it should not be used:

-h file True if file exists and is a symbolic link. This operator is retained for compatibility with previous versions of this program. Do not rely on its existence; use -L instead.

How to implement WiX installer upgrade?

This is what worked for me, even with major DOWN grade:

<Wix ...>
  <Product ...>
    <Property Id="REINSTALLMODE" Value="amus" />
    <MajorUpgrade AllowDowngrades="yes" />

Plotting histograms from grouped data in a pandas DataFrame

I write this answer because I was looking for a way to plot together the histograms of different groups. What follows is not very smart, but it works fine for me. I use Numpy to compute the histogram and Bokeh for plotting. I think it is self-explanatory, but feel free to ask for clarifications and I'll be happy to add details (and write it better).

figures = {
    'Transit': figure(title='Transit', x_axis_label='speed [km/h]', y_axis_label='frequency'),
    'Driving': figure(title='Driving', x_axis_label='speed [km/h]', y_axis_label='frequency')
}

cols = {'Vienna': 'red', 'Turin': 'blue', 'Rome': 'Orange'}
for gr in df_trips.groupby(['locality', 'means']):
    locality = gr[0][0]
    means = gr[0][1]
    fig = figures[means]
    h, b = np.histogram(pd.DataFrame(gr[1]).speed.values)
    fig.vbar(x=b[1:], top=h, width=(b[1]-b[0]), legend_label=locality, fill_color=cols[locality], alpha=0.5)

show(gridplot([
    [figures['Transit']],
    [figures['Driving']],
]))

Yum fails with - There are no enabled repos.

ok, so my problem was that I tried to install the package with yum which is the primary tool for getting, installing, deleting, querying, and managing Red Hat Enterprise Linux RPM software packages from official Red Hat software repositories, as well as other third-party repositories.

But I'm using ubuntu and The usual way to install packages on the command line in Ubuntu is with apt-get. so the right command was:

sudo apt-get install libstdc++.i686

Volley - POST/GET parameters

In your Request class (that extends Request), override the getParams() method. You would do the same for headers, just override getHeaders().

If you look at PostWithBody class in TestRequest.java in Volley tests, you'll find an example. It goes something like this

public class LoginRequest extends Request<String> {

    // ... other methods go here

    private Map<String, String> mParams;

    public LoginRequest(String param1, String param2, Listener<String> listener, ErrorListener errorListener) {
        super(Method.POST, "http://test.url", errorListener);
        mListener = listener;
        mParams = new HashMap<String, String>();
        mParams.put("paramOne", param1);
        mParams.put("paramTwo", param2);

    }

    @Override
    public Map<String, String> getParams() {
        return mParams;
    }
}

Evan Charlton was kind enough to make a quick example project to show us how to use volley. https://github.com/evancharlton/folly/

How to create a custom attribute in C#

Utilizing/Copying Darin Dimitrov's great response, this is how to access a custom attribute on a property and not a class:

The decorated property [of class Foo]:

[MyCustomAttribute(SomeProperty = "This is a custom property")]
public string MyProperty { get; set; }

Fetching it:

PropertyInfo propertyInfo = typeof(Foo).GetProperty(propertyToCheck);
object[] attribute = propertyInfo.GetCustomAttributes(typeof(MyCustomAttribute), true);
if (attribute.Length > 0)
{
    MyCustomAttribute myAttribute = (MyCustomAttribute)attribute[0];
    string propertyValue = myAttribute.SomeProperty;
}

You can throw this in a loop and use reflection to access this custom attribute on each property of class Foo, as well:

foreach (PropertyInfo propertyInfo in Foo.GetType().GetProperties())
{
    string propertyName = propertyInfo.Name;

    object[] attribute = propertyInfo.GetCustomAttributes(typeof(MyCustomAttribute), true);
    // Just in case you have a property without this annotation
    if (attribute.Length > 0)
    {
        MyCustomAttribute myAttribute = (MyCustomAttribute)attribute[0];
        string propertyValue = myAttribute.SomeProperty;
        // TODO: whatever you need with this propertyValue
    }
}

Major thanks to you, Darin!!

Find position of a node using xpath

Try:

count(a/b[.='tsr']/preceding-sibling::*)+1.

ValueError: cannot reshape array of size 30470400 into shape (50,1104,104)

In Matrix terms, the number of elements always has to equal the product of the number of rows and columns. In this particular case, the condition is not matching.

Convert string to Date in java

GregorianCalendar date;

CharSequence dateForMart = android.text.format.DateFormat.format("yyyy-MM-dd", date);

Toast.makeText(LogmeanActivity.this,dateForMart,Toast.LENGTH_LONG).show();

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

Because unreachable code is meaningless to the compiler. Whilst making code meaningful to people is both paramount and harder than making it meaningful to a compiler, the compiler is the essential consumer of code. The designers of Java take the viewpoint that code that is not meaningful to the compiler is an error. Their stance is that if you have some unreachable code, you have made a mistake that needs to be fixed.

There is a similar question here: Unreachable code: error or warning?, in which the author says "Personally I strongly feel it should be an error: if the programmer writes a piece of code, it should always be with the intention of actually running it in some scenario." Obviously the language designers of Java agree.

Whether unreachable code should prevent compilation is a question on which there will never be consensus. But this is why the Java designers did it.


A number of people in comments point out that there are many classes of unreachable code Java doesn't prevent compiling. If I understand the consequences of Gödel correctly, no compiler can possibly catch all classes of unreachable code.

Unit tests cannot catch every single bug. We don't use this as an argument against their value. Likewise a compiler can't catch all problematic code, but it is still valuable for it to prevent compilation of bad code when it can.

The Java language designers consider unreachable code an error. So preventing it compiling when possible is reasonable.


(Before you downvote: the question is not whether or not Java should have an unreachable statement compiler error. The question is why Java has an unreachable statement compiler error. Don't downvote me just because you think Java made the wrong design decision.)

How to remove .html from URL?

Thanks for your replies. I have already solved my problem. Suppose I have my pages under http://www.yoursite.com/html, the following .htaccess rules apply.

<IfModule mod_rewrite.c>
   RewriteEngine On
   RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /html/(.*).html\ HTTP/
   RewriteRule .* http://localhost/html/%1 [R=301,L]

   RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /html/(.*)\ HTTP/
   RewriteRule .* %1.html [L]
</IfModule>

Angular 2 / 4 / 5 - Set base href dynamically

Here's what we ended up doing.

Add this to index.html. It should be the first thing in the <head> section

<base href="/">
<script>
  (function() {
    window['_app_base'] = '/' + window.location.pathname.split('/')[1];
  })();
</script>

Then in the app.module.ts file, add { provide: APP_BASE_HREF, useValue: window['_app_base'] || '/' } to the list of providers, like so:

import { NgModule, enableProdMode, provide } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { APP_BASE_HREF, Location } from '@angular/common';


import { AppComponent, routing, appRoutingProviders, environment } from './';

if (environment.production) {
  enableProdMode();
}

@NgModule({
  declarations: [AppComponent],
  imports: [
    BrowserModule,
    HttpModule,
    routing],
  bootstrap: [AppComponent],
  providers: [
    appRoutingProviders,
    { provide: APP_BASE_HREF, useValue: window['_app_base'] || '/' },
  ]
})
export class AppModule { }

In CSS how do you change font size of h1 and h2

 h1 { font-size: 150%; }
 h2 { font-size: 120%; }

Tune as needed.

Remove non-ascii character in string

ASCII is in range of 0 to 127, so:

str.replace(/[^\x00-\x7F]/g, "");

What HTTP status response code should I use if the request is missing a required parameter?

I'm not sure there's a set standard, but I would have used 400 Bad Request, which the latest HTTP spec (from 2014) documents as follows:

6.5.1. 400 Bad Request

The 400 (Bad Request) status code indicates that the server cannot or will not process the request due to something that is perceived to be a client error (e.g., malformed request syntax, invalid request message framing, or deceptive request routing).

Converting a pointer into an integer

  1. #include <stdint.h>
  2. Use uintptr_t standard type defined in the included standard header file.

Android - R cannot be resolved to a variable

Agree it is probably due to a problem in resources that is preventing build of R.Java in gen. In my case a cut n paste had given a duplicate app name in string. Sort the fault, delete gen directory and clean.

Converting a String to Object

A Java String is an Object. (String extends Object.)

So you can get an Object reference via assignment/initialisation:

String a = "abc";
Object b = a;

How can I create a UIColor from a hex string?

You can create extension class of UIColor as:-

extension UIColor {

// MARK: - getColorFromHex /** This function will convert the color Hex code to RGB.

- parameter color  hex string.

- returns: RGB color code.
*/
class func getColorFromHex(hexString:String)->UIColor{

    var rgbValue : UInt32 = 0
    let scanner:NSScanner =  NSScanner(string: hexString)

    scanner.scanLocation = 1
    scanner.scanHexInt(&rgbValue)

    return UIColor(red: CGFloat((rgbValue & 0xFF0000) >> 16) / 255.0, green: CGFloat((rgbValue & 0x00FF00) >> 8) / 255.0, blue: CGFloat(rgbValue & 0x0000FF) / 255.0, alpha: CGFloat(1.0))
}

}

Freely convert between List<T> and IEnumerable<T>

A List<T> is an IEnumerable<T>, so actually, there's no need to 'convert' a List<T> to an IEnumerable<T>. Since a List<T> is an IEnumerable<T>, you can simply assign a List<T> to a variable of type IEnumerable<T>.

The other way around, not every IEnumerable<T> is a List<T> offcourse, so then you'll have to call the ToList() member method of the IEnumerable<T>.

Android Log.v(), Log.d(), Log.i(), Log.w(), Log.e() - When to use each one?

I think the point of those different types of logging is if you want your app to basically self filter its own logs. So Verbose could be to log absolutely everything of importance in your app, then the debug level would log a subset of the verbose logs, and then Info level will log a subset of the debug logs. When you get down to the Error logs, then you just want to log any sort of errors that may have occured. There is also a debug level called Fatal for when something really hits the fan in your app.

In general, you're right, it's basically arbitrary, and it's up to you to define what is considered a debug log versus informational, versus and error, etc. etc.

SQL Server equivalent of MySQL's NOW()?

getdate() 

is the direct equivalent, but you should always use UTC datetimes

getutcdate()

whether your app operates across timezones or not - otherwise you run the risk of screwing up date math at the spring/fall transitions

How to read the last row with SQL Server

OFFSET and FETCH NEXT are a feature of SQL Server 2012 to achieve SQL paging while displaying results.

The OFFSET argument is used to decide the starting row to return rows from a result and FETCH argument is used to return a set of number of rows.

SELECT *
FROM table_name
ORDER BY unique_column desc
OFFSET 0 Row
FETCH NEXT 1 ROW ONLY

PostgreSQL function for last inserted ID

Leonbloy's answer is quite complete. I would only add the special case in which one needs to get the last inserted value from within a PL/pgSQL function where OPTION 3 doesn't fit exactly.

For example, if we have the following tables:

CREATE TABLE person(
   id serial,
   lastname character varying (50),
   firstname character varying (50),
   CONSTRAINT person_pk PRIMARY KEY (id)
);

CREATE TABLE client (
    id integer,
   CONSTRAINT client_pk PRIMARY KEY (id),
   CONSTRAINT fk_client_person FOREIGN KEY (id)
       REFERENCES person (id) MATCH SIMPLE
);

If we need to insert a client record we must refer to a person record. But let's say we want to devise a PL/pgSQL function that inserts a new record into client but also takes care of inserting the new person record. For that, we must use a slight variation of leonbloy's OPTION 3:

INSERT INTO person(lastname, firstname) 
VALUES (lastn, firstn) 
RETURNING id INTO [new_variable];

Note that there are two INTO clauses. Therefore, the PL/pgSQL function would be defined like:

CREATE OR REPLACE FUNCTION new_client(lastn character varying, firstn character varying)
  RETURNS integer AS
$BODY$
DECLARE
   v_id integer;
BEGIN
   -- Inserts the new person record and retrieves the last inserted id
   INSERT INTO person(lastname, firstname)
   VALUES (lastn, firstn)
   RETURNING id INTO v_id;

   -- Inserts the new client and references the inserted person
   INSERT INTO client(id) VALUES (v_id);

   -- Return the new id so we can use it in a select clause or return the new id into the user application
    RETURN v_id;
END;
$BODY$
  LANGUAGE plpgsql VOLATILE;

Now we can insert the new data using:

SELECT new_client('Smith', 'John');

or

SELECT * FROM new_client('Smith', 'John');

And we get the newly created id.

new_client
integer
----------
         1

rsync - mkstemp failed: Permission denied (13)

I imagine a common error not currently mentioned above is trying to write to a mount space (e.g., /media/drivename) when the partition isn't mounted. That will produce this error as well.

If it's an encrypted drive set to auto-mount but doesn't, might be an issue of auto-unlocking the encrypted partition before attempting to write to the space where it is supposed to be mounted.

Set value for particular cell in pandas DataFrame with iloc

For mixed position and index, use .ix. BUT you need to make sure that your index is not of integer, otherwise it will cause confusions.

df.ix[0, 'COL_NAME'] = x

Update:

Alternatively, try

df.iloc[0, df.columns.get_loc('COL_NAME')] = x

Example:

import pandas as pd
import numpy as np

# your data
# ========================
np.random.seed(0)
df = pd.DataFrame(np.random.randn(10, 2), columns=['col1', 'col2'], index=np.random.randint(1,100,10)).sort_index()

print(df)


      col1    col2
10  1.7641  0.4002
24  0.1440  1.4543
29  0.3131 -0.8541
32  0.9501 -0.1514
33  1.8676 -0.9773
36  0.7610  0.1217
56  1.4941 -0.2052
58  0.9787  2.2409
75 -0.1032  0.4106
76  0.4439  0.3337

# .iloc with get_loc
# ===================================
df.iloc[0, df.columns.get_loc('col2')] = 100

df

      col1      col2
10  1.7641  100.0000
24  0.1440    1.4543
29  0.3131   -0.8541
32  0.9501   -0.1514
33  1.8676   -0.9773
36  0.7610    0.1217
56  1.4941   -0.2052
58  0.9787    2.2409
75 -0.1032    0.4106
76  0.4439    0.3337

How to remove the default arrow icon from a dropdown list (select element)?

Works for all browsers and all versions:

JS

jQuery(document).ready(function () {    
    var widthOfSelect = $("#first").width();
    widthOfSelect = widthOfSelect - 13;
    //alert(widthOfSelect);
    jQuery('#first').wrap("<div id='sss' style='width: "+widthOfSelect+"px; overflow: hidden; border-right: #000 1px solid;' width=20></div>");
});

HTML

<select class="first" id="first">
  <option>option1</option>
  <option>option2</option>
  <option>option3</option>
</select>

Inline <style> tags vs. inline css properties

It depends.

The main point is to avoid repeated code.

If the same code need to be re-used 2 times or more, and should be in sync when change, use external style sheet.

If you only use it once, I think inline is ok.

Fixed position but relative to container

When you use position:fixed CSS rule and try to apply top/left/right/bottom it position the element relative to window.

A workaround is to use margin properties instead of top/left/right/bottom

How to use the DropDownList's SelectedIndexChanged event

You should add AutoPostBack="true" to DropDownList1

                <asp:DropDownList ID="ddmanu" runat="server" AutoPostBack="true"
                    DataSourceID="Sql_fur_model_manu"    
                    DataTextField="manufacturer" DataValueField="manufacturer" 
                    onselectedindexchanged="ddmanu_SelectedIndexChanged">
                </asp:DropDownList>

Xcode 4 - "Valid signing identity not found" error on provisioning profiles on a new Macintosh install

With Xcode 4.2 and later versions, including Xcode 4.6, there is a better way to migrate your entire developer profile to a new machine. On your existing machine, launch Xcode and do this:

  1. Open the Organizer (Shift-Command-2).
  2. Select the Devices tab.
  3. Choose Developer Profile in the upper-left corner under LIBRARY, which may be under the heading library or under a heading called TEAMS.
  4. Choose Export near the bottom left side of the window. Xcode asks you to choose a file name and password.

Edit for Xcode 4.4:

With Xcode 4.4, at step 3 choose Provisioning Profiles under LIBRARY. Then select your provisioning profiles either with the mouse or Command-A.

Also, Apple is making improvements in the way they manage this aspect of Xcode, and some users have reported that the Refresh button in the lower-right corner does the trick. So try clicking Refresh first, and if that doesn't help, do the export/import sequence.

Picture for Xcode 4.6 added by WP

screenshot of enter password to secure developer profile

Edit for Xcode 5.0 or newer:

  1. Open Xcode -> Preferences ('Command' + ',')
  2. Select the Apple ID from the list.
  3. Click on the SETTING icon near the bottom-left corner of window, and choose EXPORT ACCOUNTS... Xcode asks you to choose a file name and password.

On your new machine, launch Xcode and import the profile you exported above. Works like a charm.

Picture for Xcode 5.0 added by Ankur

For Xcode 5 or newer versions

Explain ggplot2 warning: "Removed k rows containing missing values"

The behavior you're seeing is due to how ggplot2 deals with data that are outside the axis ranges of the plot. You can change this behavior depending on whether you use scale_y_continuous (or, equivalently, ylim) or coord_cartesian to set axis ranges, as explained below.

library(ggplot2)

# All points are visible in the plot
ggplot(mtcars, aes(mpg, hp)) + 
  geom_point()

In the code below, one point with hp = 335 is outside the y-range of the plot. Also, because we used scale_y_continuous to set the y-axis range, this point is not included in any other statistics or summary measures calculated by ggplot, such as the linear regression line.

ggplot(mtcars, aes(mpg, hp)) + 
  geom_point() +
  scale_y_continuous(limits=c(0,300)) +  # Change this to limits=c(0,335) and the warning disappars
  geom_smooth(method="lm")

Warning messages:
1: Removed 1 rows containing missing values (stat_smooth). 
2: Removed 1 rows containing missing values (geom_point).

In the code below, the point with hp = 335 is still outside the y-range of the plot, but this point is nevertheless included in any statistics or summary measures that ggplot calculates, such as the linear regression line. This is because we used coord_cartesian to set the y-axis range, and this function does not exclude points that are outside the plot ranges when it does other calculations on the data.

If you compare this and the previous plot, you can see that the linear regression line in the second plot has a slightly steeper slope, because the point with hp=335 is included when calculating the regression line, even though it's not visible in the plot.

ggplot(mtcars, aes(mpg, hp)) + 
  geom_point() +
  coord_cartesian(ylim=c(0,300)) +
  geom_smooth(method="lm")

How can you tell if a value is not numeric in Oracle?

You can use the following regular expression which will match integers (e.g., 123), floating-point numbers (12.3), and numbers with exponents (1.2e3):

^-?\d*\.?\d+([eE]-?\d+)?$

If you want to accept + signs as well as - signs (as Oracle does with TO_NUMBER()), you can change each occurrence of - above to [+-]. So you might rewrite your block of code above as follows:

IF (option_id = 0021) THEN 
    IF NOT REGEXP_LIKE(value, '^[+-]?\d*\.?\d+([eE][+-]?\d+)?$') OR TO_NUMBER(value) < 10000 OR TO_NUMBER(value) > 7200000 THEN
        ip_msg(6214,option_name);
        RETURN;
    END IF;
END IF;

I am not altogether certain that would handle all values so you may want to add an EXCEPTION block or write a custom to_number() function as @JustinCave suggests.

How to loop over files in directory and change path and add suffix to filename

for file in Data/*.txt
do
    for ((i = 0; i < 3; i++))
    do
        name=${file##*/}
        base=${name%.txt}
        ./MyProgram.exe "$file" Logs/"${base}_Log$i.txt"
    done
done

The name=${file##*/} substitution (shell parameter expansion) removes the leading pathname up to the last /.

The base=${name%.txt} substitution removes the trailing .txt. It's a bit trickier if the extensions can vary.

Referencing another schema in Mongoose

Late reply, but adding that Mongoose also has the concept of Subdocuments

With this syntax, you should be able to reference your userSchema as a type in your postSchema like so:

var userSchema = new Schema({
    twittername: String,
    twitterID: Number,
    displayName: String,
    profilePic: String,
});

var postSchema = new Schema({
    name: String,
    postedBy: userSchema,
    dateCreated: Date,
    comments: [{body:"string", by: mongoose.Schema.Types.ObjectId}],
});

Note the updated postedBy field with type userSchema.

This will embed the user object within the post, saving an extra lookup required by using a reference. Sometimes this could be preferable, other times the ref/populate route might be the way to go. Depends on what your application is doing.

Simulating Button click in javascript

The smallest change to fix this would be to change

onClick="document.getElementById("datepicker").click()">

to

onClick="$('#datepicker').click()">

click() is a jQuery method. Also, you had a collision between the double-quotes used for the HTML element attribute and those use for the JavaScript function argument.

How to get the EXIF data from a file using C#

Recently, I used this .NET Metadata API. I have also written a blog post about it, that shows reading, updating, and removing the EXIF data from images using C#.

using (Metadata metadata = new Metadata("image.jpg"))
{
    IExif root = metadata.GetRootPackage() as IExif;
    if (root != null && root.ExifPackage != null)
    {
        Console.WriteLine(root.ExifPackage.DateTime);
     }
}

Specifying colClasses in the read.csv

If we combine what @Hendy and @Oddysseus Ithaca contributed, we get cleaner and a more general (i.e., adaptable?) chunk of code.

    data <- read.csv("test.csv", head = F, colClasses = c(V36 = "character", V38 = "character"))                        

SVG gradient using CSS

Just use in the CSS whatever you would use in a fill attribute. Of course, this requires that you have defined the linear gradient somewhere in your SVG.

Here is a complete example:

_x000D_
_x000D_
rect {_x000D_
    cursor: pointer;_x000D_
    shape-rendering: crispEdges;_x000D_
    fill: url(#MyGradient);_x000D_
}
_x000D_
<svg width="100" height="50" version="1.1" xmlns="http://www.w3.org/2000/svg">_x000D_
      <style type="text/css">_x000D_
        rect{fill:url(#MyGradient)}_x000D_
      </style>_x000D_
      <defs>_x000D_
        <linearGradient id="MyGradient">_x000D_
          <stop offset="5%" stop-color="#F60" />_x000D_
          <stop offset="95%" stop-color="#FF6" />_x000D_
        </linearGradient>_x000D_
      </defs>_x000D_
      _x000D_
      <rect width="100" height="50"/>_x000D_
    </svg>
_x000D_
_x000D_
_x000D_

Retrieving a random item from ArrayList

your print comes after you return -- you can never reach that statement. Also, you never declared anyItem to be a variable. You might want

public Item anyItem()
    {
        int index = randomGenerator.nextInt(catalogue.size());
        Item randomItem = catalogue.get(index);
        System.out.println("Managers choice this week" + randomItem.toString() + "our recommendation to you");
        return randomItem;
    }

The toString part is just a quickie -- you might want to add a method 'getItemDescription' that returns a useful String for this purpose...

range() for floats

This can be done with numpy.arange(start, stop, stepsize)

import numpy as np

np.arange(0.5,5,1.5)
>> [0.5, 2.0, 3.5, 5.0]

# OBS you will sometimes see stuff like this happening, 
# so you need to decide whether that's not an issue for you, or how you are going to catch it.
>> [0.50000001, 2.0, 3.5, 5.0]

Note 1: From the discussion in the comment section here, "never use numpy.arange() (the numpy documentation itself recommends against it). Use numpy.linspace as recommended by wim, or one of the other suggestions in this answer"

Note 2: I have read the discussion in a few comments here, but after coming back to this question for the third time now, I feel this information should be placed in a more readable position.

Subset data.frame by date

The first thing you should do with date variables is confirm that R reads it as a Date. To do this, for the variable (i.e. vector/column) called Date, in the data frame called EPL2011_12, input

class(EPL2011_12$Date)

The output should read [1] "Date". If it doesn't, you should format it as a date by inputting

EPL2011_12$Date <- as.Date(EPL2011_12$Date, "%d-%m-%y")

Note that the hyphens in the date format ("%d-%m-%y") above can also be slashes ("%d/%m/%y"). Confirm that R sees it as a Date. If it doesn't, try a different formatting command

EPL2011_12$Date <- format(EPL2011_12$Date, format="%d/%m/%y")

Once you have it in Date format, you can use the subset command, or you can use brackets

WhateverYouWant <- EPL2011_12[EPL2011_12$Date > as.Date("2014-12-15"),]

How to align this span to the right of the div?

The solution using flexbox without justify-content: space-between.

<div class="title">
  <span>Cumulative performance</span>
  <span>20/02/2011</span>
</div>

.title {
  display: flex;
}

span:first-of-type {
  flex: 1;
}

When we use flex:1 on the first <span>, it takes up the entire remaining space and moves the second <span> to the right. The Fiddle with this solution: https://jsfiddle.net/2k1vryn7/

Here https://jsfiddle.net/7wvx2uLp/3/ you can see the difference between two flexbox approaches: flexbox with justify-content: space-between and flexbox with flex:1 on the first <span>.

How do you generate a random double uniformly distributed between 0 and 1 from C++?

In C++11 and C++14 we have much better options with the random header. The presentation rand() Considered Harmful by Stephan T. Lavavej explains why we should eschew the use of rand() in C++ in favor of the random header and N3924: Discouraging rand() in C++14 further reinforces this point.

The example below is a modified version of the sample code on the cppreference site and uses the std::mersenne_twister_engine engine and the std::uniform_real_distribution which generates numbers in the [0,1) range (see it live):

#include <iostream>
#include <iomanip>
#include <map>
#include <random>

int main()
{
    std::random_device rd;


    std::mt19937 e2(rd());

    std::uniform_real_distribution<> dist(0, 1);

    std::map<int, int> hist;
    for (int n = 0; n < 10000; ++n) {
        ++hist[std::round(dist(e2))];
    }

    for (auto p : hist) {
        std::cout << std::fixed << std::setprecision(1) << std::setw(2)
                  << p.first << ' ' << std::string(p.second/200, '*') << '\n';
    }
}

output will be similar to the following:

0 ************************
1 *************************

Since the post mentioned that speed was important then we should consider the cppreference section that describes the different random number engines (emphasis mine):

The choice of which engine to use involves a number of tradeoffs*: the **linear congruential engine is moderately fast and has a very small storage requirement for state. The lagged Fibonacci generators are very fast even on processors without advanced arithmetic instruction sets, at the expense of greater state storage and sometimes less desirable spectral characteristics. The Mersenne twister is slower and has greater state storage requirements but with the right parameters has the longest non-repeating sequence with the most desirable spectral characteristics (for a given definition of desirable).

So if there is a desire for a faster generator perhaps ranlux24_base or ranlux48_base are better choices over mt19937.

rand()

If you forced to use rand() then the C FAQ for a guide on How can I generate floating-point random numbers?, gives us an example similar to this for generating an on the interval [0,1):

#include <stdlib.h>

double randZeroToOne()
{
    return rand() / (RAND_MAX + 1.);
}

and to generate a random number in the range from [M,N):

double randMToN(double M, double N)
{
    return M + (rand() / ( RAND_MAX / (N-M) ) ) ;  
}

How do I change the string representation of a Python class?

This is not as easy as it seems, some core library functions don't work when only str is overwritten (checked with Python 2.7), see this thread for examples How to make a class JSON serializable Also, try this

import json

class A(unicode):
    def __str__(self):
        return 'a'
    def __unicode__(self):
        return u'a'
    def __repr__(self):
        return 'a'

a = A()
json.dumps(a)

produces

'""'

and not

'"a"'

as would be expected.

EDIT: answering mchicago's comment:

unicode does not have any attributes -- it is an immutable string, the value of which is hidden and not available from high-level Python code. The json module uses re for generating the string representation which seems to have access to this internal attribute. Here's a simple example to justify this:

b = A('b') print b

produces

'a'

while

json.dumps({'b': b})

produces

{"b": "b"}

so you see that the internal representation is used by some native libraries, probably for performance reasons.

See also this for more details: http://www.laurentluce.com/posts/python-string-objects-implementation/

Detect all changes to a <input type="text"> (immediately) using JQuery

Binding to the oninput event seems to work fine in most sane browsers. IE9 supports it too, but the implementation is buggy (the event is not fired when deleting characters).

With jQuery version 1.7+ the on method is useful to bind to the event like this:

$(".inputElement").on("input", null, null, callbackFunction);

Change the project theme in Android Studio?

In Manifest theme sets with style name (AppTheme and myDialog)/ You can set new styles in styles.xml

        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".MyActivity2"
        android:label="@string/title_activity_my_activity2"
        android:theme="@style/myDialog"
        >
    </activity>
</application>

styles.xml example

<resources>

<!-- Base application theme. -->
<style name="AppTheme" parent="android:Theme.Black">
    <!-- Customize your theme here. -->
</style>

<style name="myDialog" parent="android:Theme.Dialog">

</style>

In parent you set actualy the theme

Best way to convert string to bytes in Python 3?

If you look at the docs for bytes, it points you to bytearray:

bytearray([source[, encoding[, errors]]])

Return a new array of bytes. The bytearray type is a mutable sequence of integers in the range 0 <= x < 256. It has most of the usual methods of mutable sequences, described in Mutable Sequence Types, as well as most methods that the bytes type has, see Bytes and Byte Array Methods.

The optional source parameter can be used to initialize the array in a few different ways:

If it is a string, you must also give the encoding (and optionally, errors) parameters; bytearray() then converts the string to bytes using str.encode().

If it is an integer, the array will have that size and will be initialized with null bytes.

If it is an object conforming to the buffer interface, a read-only buffer of the object will be used to initialize the bytes array.

If it is an iterable, it must be an iterable of integers in the range 0 <= x < 256, which are used as the initial contents of the array.

Without an argument, an array of size 0 is created.

So bytes can do much more than just encode a string. It's Pythonic that it would allow you to call the constructor with any type of source parameter that makes sense.

For encoding a string, I think that some_string.encode(encoding) is more Pythonic than using the constructor, because it is the most self documenting -- "take this string and encode it with this encoding" is clearer than bytes(some_string, encoding) -- there is no explicit verb when you use the constructor.

Edit: I checked the Python source. If you pass a unicode string to bytes using CPython, it calls PyUnicode_AsEncodedString, which is the implementation of encode; so you're just skipping a level of indirection if you call encode yourself.

Also, see Serdalis' comment -- unicode_string.encode(encoding) is also more Pythonic because its inverse is byte_string.decode(encoding) and symmetry is nice.

bash: mkvirtualenv: command not found

Solution 1:

For some reason, virtualenvwrapper.sh installed in /usr/bin/virtualenvwrapper.sh, instead of under /usr/local/bin.

The following in my .bash_profile works...

source "/usr/bin/virtualenvwrapper.sh"
export WORKON_HOME="/opt/virtual_env/"

My install seems to work fine without sourcing virtualenvwrapper_bashrc

Solution 2:

Alternatively as mentioned below, you could leverage the chance that virtualenvwrapper.sh is already in your shell's PATH and just issue a source `which virtualenvwrapper.sh`

How to get second-highest salary employees in a table

Try this

select * from (
   select ROW_NUMBER() over (order by [salary] desc) as sno,emp_name,   
   [salary] from [dbo].[Emp]
) t 
where t.sno =10

with t as
select top (1) * from       
  (select top (2) emp_name,salary from   [Emp]  e
   order by  salary desc) t
order  by salary asc

Activity has leaked window that was originally added

You're trying to show a Dialog after you've exited an Activity.

[EDIT]

This question is one of the top search on google for android developer, therefore Adding few important points from comments, which might be more helpful for future investigator without going in depth of comment conversation.

Answer 1 :

You're trying to show a Dialog after you've exited an Activity.

Answer 2

This error can be a little misleading in some circumstances (although the answer is still completely accurate) - i.e. in my case an unhandled Exception was thrown in an AsyncTask, which caused the Activity to shutdown, then an open progressdialog caused this Exception.. so the 'real' exception was a little earlier in the log

Answer 3

Call dismiss() on the Dialog instance you created before exiting your Activity, e.g. in onPause() or onDestroy()

How to combine two lists in R

I was looking to do the same thing, but to preserve the list as a just an array of strings so I wrote a new code, which from what I've been reading may not be the most efficient but worked for what i needed to do:

combineListsAsOne <-function(list1, list2){
  n <- c()
  for(x in list1){
    n<-c(n, x)
  }
  for(y in list2){
    n<-c(n, y)
  }
  return(n)
}

It just creates a new list and adds items from two supplied lists to create one.

origin 'http://localhost:4200' has been blocked by CORS policy in Angular7

If your project is .net Core 3.1 API project.

update your Startup.cs in your .net core project to:

public class Startup
{
    public Startup(IConfiguration configuration)
    {
        Configuration = configuration;
    }

    public IConfiguration Configuration { get; }
    readonly string MyAllowSpecificOrigins = "_myAllowSpecificOrigins";
    // This method gets called by the runtime. Use this method to add services to the container.
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddCors(options =>
        {
            options.AddPolicy(MyAllowSpecificOrigins,
            builder =>
            {
                builder.WithOrigins("http://localhost:53135",
                                    "http://localhost:4200"
                                    )
                                    .AllowAnyHeader()
                                    .AllowAnyMethod();
            });
        });
        services.AddDbContext<CIVDataContext>(options =>
        options.UseSqlServer(Configuration.GetConnectionString("CIVDatabaseConnection")));
        services.AddControllers();
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }
        app.UseCors(MyAllowSpecificOrigins);

        app.UseRouting();

        app.UseAuthorization();

        app.UseEndpoints(endpoints =>
        {
            endpoints.MapControllers();
        });

       
    }
}

Dealing with "Xerces hell" in Java/Maven?

What would help, except for excluding, is modular dependencies.

With one flat classloading (standalone app), or semi-hierarchical (JBoss AS/EAP 5.x) this was a problem.

But with modular frameworks like OSGi and JBoss Modules, this is not so much pain anymore. The libraries may use whichever library they want, independently.

Of course, it's still most recommendable to stick with just a single implementation and version, but if there's no other way (using extra features from more libs), then modularizing might save you.

A good example of JBoss Modules in action is, naturally, JBoss AS 7 / EAP 6 / WildFly 8, for which it was primarily developed.

Example module definition:

<?xml version="1.0" encoding="UTF-8"?>
<module xmlns="urn:jboss:module:1.1" name="org.jboss.msc">
    <main-class name="org.jboss.msc.Version"/>
    <properties>
        <property name="my.property" value="foo"/>
    </properties>
    <resources>
        <resource-root path="jboss-msc-1.0.1.GA.jar"/>
    </resources>
    <dependencies>
        <module name="javax.api"/>
        <module name="org.jboss.logging"/>
        <module name="org.jboss.modules"/>
        <!-- Optional deps -->
        <module name="javax.inject.api" optional="true"/>
        <module name="org.jboss.threads" optional="true"/>
    </dependencies>
</module>

In comparison with OSGi, JBoss Modules is simpler and faster. While missing certain features, it's sufficient for most projects which are (mostly) under control of one vendor, and allow stunning fast boot (due to paralelized dependencies resolving).

Note that there's a modularization effort underway for Java 8, but AFAIK that's primarily to modularize the JRE itself, not sure whether it will be applicable to apps.

SELECT INTO using Oracle

If NEW_TABLE already exists then ...

insert into new_table 
select * from old_table
/

If you want to create NEW_TABLE based on the records in OLD_TABLE ...

create table new_table as 
select * from old_table
/

If the purpose is to create a new but empty table then use a WHERE clause with a condition which can never be true:

create table new_table as 
select * from old_table
where 1 = 2
/

Remember that CREATE TABLE ... AS SELECT creates only a table with the same projection as the source table. The new table does not have any constraints, triggers or indexes which the original table might have. Those still have to be added manually (if they are required).

Passing route control with optional parameter after root in express?

Express version:

"dependencies": {
    "body-parser": "^1.19.0",
    "express": "^4.17.1"
  }

Optional parameter are very much handy, you can declare and use them easily using express:

app.get('/api/v1/tours/:cId/:pId/:batchNo?', (req, res)=>{
    console.log("category Id: "+req.params.cId);
    console.log("product ID: "+req.params.pId);
    if (req.params.batchNo){
        console.log("Batch No: "+req.params.batchNo);
    }
});

In the above code batchNo is optional. Express will count it optional because after in URL construction, I gave a '?' symbol after batchNo '/:batchNo?'

Now I can call with only categoryId and productId or with all three-parameter.

http://127.0.0.1:3000/api/v1/tours/5/10
//or
http://127.0.0.1:3000/api/v1/tours/5/10/8987

enter image description here enter image description here

What is difference between MVC, MVP & MVVM design pattern in terms of coding c#

The image below is from the article written by Erwin van der Valk:

image explaining MVC, MVP and MVVM - by Erwin Vandervalk

The article explains the differences and gives some code examples in C#

Reading column names alone in a csv file

here is the code to print only the headers or columns of the csv file.

import csv
HEADERS = next(csv.reader(open('filepath.csv')))
print (HEADERS)

Another method with pandas

import pandas as pd
HEADERS = list(pd.read_csv('filepath.csv').head(0))
print (HEADERS)

ORA-03113: end-of-file on communication channel after long inactivity in ASP.Net app

You could try this registry hack:

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters]
"DeadGWDetectDefault"=dword:00000001
"KeepAliveTime"=dword:00120000

If it works, just keep increasing the KeepAliveTime. It is currently set for 2 minutes.

How do I alter the precision of a decimal column in Sql Server?

ALTER TABLE (Your_Table_Name) MODIFY (Your_Column_Name) DATA_TYPE();

For you problem:

ALTER TABLE (Your_Table_Name) MODIFY (Your_Column_Name) DECIMAL(Precision, Scale); 

Add image to layout in ruby on rails

When using the new ruby, the image folder will go to asset folder on folder app

after placing your images in image folder, use

<%=image_tag("example_image.png", alt: "Example Image")%>

How to detect internet speed in JavaScript?

I needed a quick way to determine if the user connection speed was fast enough to enable/disable some features in a site I’m working on, I made this little script that averages the time it takes to download a single (small) image a number of times, it's working pretty accurately in my tests, being able to clearly distinguish between 3G or Wi-Fi for example, maybe someone can make a more elegant version or even a jQuery plugin.

_x000D_
_x000D_
var arrTimes = [];_x000D_
var i = 0; // start_x000D_
var timesToTest = 5;_x000D_
var tThreshold = 150; //ms_x000D_
var testImage = "http://www.google.com/images/phd/px.gif"; // small image in your server_x000D_
var dummyImage = new Image();_x000D_
var isConnectedFast = false;_x000D_
_x000D_
testLatency(function(avg){_x000D_
  isConnectedFast = (avg <= tThreshold);_x000D_
  /** output */_x000D_
  document.body.appendChild(_x000D_
    document.createTextNode("Time: " + (avg.toFixed(2)) + "ms - isConnectedFast? " + isConnectedFast)_x000D_
  );_x000D_
});_x000D_
_x000D_
/** test and average time took to download image from server, called recursively timesToTest times */_x000D_
function testLatency(cb) {_x000D_
  var tStart = new Date().getTime();_x000D_
  if (i<timesToTest-1) {_x000D_
    dummyImage.src = testImage + '?t=' + tStart;_x000D_
    dummyImage.onload = function() {_x000D_
      var tEnd = new Date().getTime();_x000D_
      var tTimeTook = tEnd-tStart;_x000D_
      arrTimes[i] = tTimeTook;_x000D_
      testLatency(cb);_x000D_
      i++;_x000D_
    };_x000D_
  } else {_x000D_
    /** calculate average of array items then callback */_x000D_
    var sum = arrTimes.reduce(function(a, b) { return a + b; });_x000D_
    var avg = sum / arrTimes.length;_x000D_
    cb(avg);_x000D_
  }_x000D_
}
_x000D_
_x000D_
_x000D_

HTTP URL Address Encoding in Java

I read the previous answers to write my own method because I could not have something properly working using the solution of the previous answers, it looks good for me but if you can find URL that does not work with this, please let me know.

public static URL convertToURLEscapingIllegalCharacters(String toEscape) throws MalformedURLException, URISyntaxException {
            URL url = new URL(toEscape);
            URI uri = new URI(url.getProtocol(), url.getUserInfo(), url.getHost(), url.getPort(), url.getPath(), url.getQuery(), url.getRef());
            //if a % is included in the toEscape string, it will be re-encoded to %25 and we don't want re-encoding, just encoding
            return new URL(uri.toString().replace("%25", "%"));
}

OpenCV TypeError: Expected cv::UMat for argument 'src' - What is this?

that is referring to the expected dtype of your image
"image".astype('float32') should solve your issue

Getting Textbox value in Javascript

<script type="text/javascript" runat="server">
 public void Page_Load(object Sender, System.EventArgs e)
    {
        double rad=0.0;
        TextBox1.Attributes.Add("Visible", "False");
        if (TextBox1.Text != "") 
        rad = Convert.ToDouble(TextBox1.Text);    
        Button1.Attributes.Add("OnClick","alert("+ rad +")");
    }
</script>

<asp:Button ID="Button1" runat="server" Text="Diameter" 
            style="z-index: 1; left: 133px; top: 181px; position: absolute" />
<asp:TextBox ID="TextBox1" Visible="True" Text="" runat="server" 
            AutoPostBack="true" 
            style="z-index: 1; left: 134px; top: 133px; position: absolute" ></asp:TextBox>

use the help of this, hope it will be usefull

Google Gson - deserialize list<class> object? (generic type)

Another way is to use an array as a type, e.g.:

MyClass[] mcArray = gson.fromJson(jsonString, MyClass[].class);

This way you avoid all the hassle with the Type object, and if you really need a list you can always convert the array to a list by:

List<MyClass> mcList = Arrays.asList(mcArray);

IMHO this is much more readable.

And to make it be an actual list (that can be modified, see limitations of Arrays.asList()) then just do the following:

List<MyClass> mcList = new ArrayList<>(Arrays.asList(mcArray));

Proper use cases for Android UserManager.isUserAGoat()?

This appears to be an inside joke at Google. It's also featured in the Google Chrome task manager. It has no purpose, other than some engineers finding it amusing. Which is a purpose by itself, if you will.

  1. In Chrome, open the Task Manager with Shift+Esc.
  2. Right click to add the Goats Teleported column.
  3. Wonder.

There is even a huge Chromium bug report about too many teleported goats.

chrome

The following Chromium source code snippet is stolen from the HN comments.

int TaskManagerModel::GetGoatsTeleported(int index) const {
  int seed = goat_salt_ * (index + 1);
  return (seed >> 16) & 255;
}

Access-Control-Allow-Origin Multiple Origin Domains?

Here's how to echo the Origin header back if it matches your domain with Nginx, this is useful if you want to serve a font multiple sub-domains:

location /fonts {
    # this will echo back the origin header
    if ($http_origin ~ "example.org$") {
        add_header "Access-Control-Allow-Origin" $http_origin;
    }
}

JavaScript Chart.js - Custom data formatting to display on tooltip

For chart.js 2.0+, this has changed (no more tooltipTemplate/multiTooltipTemplate). For those that just want to access the current, unformatted value and start tweaking it, the default tooltip is the same as:

options: {
    tooltips: {
        callbacks: {
            label: function(tooltipItem, data) {
                return tooltipItem.yLabel;
            }
        }
    }
}

I.e., you can return modifications to tooltipItem.yLabel, which holds the y-axis value. In my case, I wanted to add a dollar sign, rounding, and thousands commas for a financial chart, so I used:

options: {
    tooltips: {
        callbacks: {
            label: function(tooltipItem, data) {
                return "$" + Number(tooltipItem.yLabel).toFixed(0).replace(/./g, function(c, i, a) {
                    return i > 0 && c !== "." && (a.length - i) % 3 === 0 ? "," + c : c;
                });
            }
        }
    }
}

Javascript String to int conversion

If you are sure id.substring(indexPos) is a number, you can do it like so:

var number = Number(id.substring(indexPos)) + 1;

Otherwise I suggest checking if the Number function evaluates correctly.

Regular expressions inside SQL Server

stored value in DB is: 5XXXXXX [where x can be any digit]

You don't mention data types - if numeric, you'll likely have to use CAST/CONVERT to change the data type to [n]varchar.

Use:

WHERE CHARINDEX(column, '5') = 1
  AND CHARINDEX(column, '.') = 0 --to stop decimals if needed
  AND ISNUMERIC(column) = 1

References:

i have also different cases like XXXX7XX for example, so it has to be generic.

Use:

WHERE PATINDEX('%7%', column) = 5
  AND CHARINDEX(column, '.') = 0 --to stop decimals if needed
  AND ISNUMERIC(column) = 1

References:

Regex Support

SQL Server 2000+ supports regex, but the catch is you have to create the UDF function in CLR before you have the ability. There are numerous articles providing example code if you google them. Once you have that in place, you can use:

  • 5\d{6} for your first example
  • \d{4}7\d{2} for your second example

For more info on regular expressions, I highly recommend this website.

Illegal mix of collations MySQL Error

Use following statement for error

be careful about your data take backup if data have in table.

 ALTER TABLE your_table_name CONVERT TO CHARACTER SET utf8 COLLATE utf8_general_ci;

Handling Enter Key in Vue.js

For enter event handling you can use

  1. @keyup.enter or
  2. @keyup.13

13 is the keycode of enter. For @ key event, the keycode is 50. So you can use @keyup.50.

For example:

<input @keyup.50="atPress()" />

Repair all tables in one go

I like this for a simple check from the shell:

mysql -p<password> -D<database> -B -e "SHOW TABLES LIKE 'User%'" \
| awk 'NR != 1 {print "CHECK TABLE "$1";"}' \
| mysql -p<password> -D<database>

Already defined in .obj - no double inclusions

You probably don't want to do this:

#include "client.cpp"

A *.cpp file will have been compiled by the compiler as part of your build. By including it in other files, it will be compiled again (and again!) in every file in which you include it.

Now here's the thing: You are guarding it with #ifndef SOCKET_CLIENT_CLASS, however, each file that has #include "client.cpp" is built independently and as such will find SOCKET_CLIENT_CLASS not yet defined. Therefore it's contents will be included, not #ifdef'd out.

If it contains any definitions at all (rather than just declarations) then these definitions will be repeated in every file where it's included.

Can I get the name of the currently running function in JavaScript?

For non-anonymous functions

function foo()
{ 
    alert(arguments.callee.name)
}

But in case of an error handler the result would be the name of the error handler function, wouldn't it?

Java Strings: "String s = new String("silly");"

In most versions of the JDK the two versions will be the same:

String s = new String("silly");

String s = "No longer silly";

Because strings are immutable the compiler maintains a list of string constants and if you try to make a new one will first check to see if the string is already defined. If it is then a reference to the existing immutable string is returned.

To clarify - when you say "String s = " you are defining a new variable which takes up space on the stack - then whether you say "No longer silly" or new String("silly") exactly the same thing happens - a new constant string is compiled into your application and the reference points to that.

I dont see the distinction here. However for your own class, which is not immutable, this behaviour is irrelevant and you must call your constructor.

UPDATE: I was wrong! Based on a down vote and comment attached I tested this and realise that my understanding is wrong - new String("Silly") does indeed create a new string rather than reuse the existing one. I am unclear why this would be (what is the benefit?) but code speaks louder than words!

Visualizing decision tree in scikit-learn

Here is one liner for those who are using jupyter and sklearn(18.2+) You don't even need matplotlib for that. Only requirement is graphviz

pip install graphviz

than run (according to code in question X is a pandas DataFrame)

from graphviz import Source
from sklearn import tree
Source( tree.export_graphviz(dtreg, out_file=None, feature_names=X.columns))

This will display it in SVG format. Code above produces Graphviz's Source object (source_code - not scary) That would be rendered directly in jupyter.

Some things you are likely to do with it

Display it in jupter:

from IPython.display import SVG
graph = Source( tree.export_graphviz(dtreg, out_file=None, feature_names=X.columns))
SVG(graph.pipe(format='svg'))

Save as png:

graph = Source( tree.export_graphviz(dtreg, out_file=None, feature_names=X.columns))
graph.format = 'png'
graph.render('dtree_render',view=True)

Get the png image, save it and view it:

graph = Source( tree.export_graphviz(dtreg, out_file=None, feature_names=X.columns))
png_bytes = graph.pipe(format='png')
with open('dtree_pipe.png','wb') as f:
    f.write(png_bytes)

from IPython.display import Image
Image(png_bytes)

If you are going to play with that lib here are the links to examples and userguide

HTTP Status 504

You can't. The problem is not that your app is impatient and timing out; the problem is that an intermediate proxy is impatient and timing out. "The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server specified by the URI." (http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.5.5) It most likely indicates that the origin server is having some sort of issue, so it's not responding quickly to the forwarded request.

Possible solutions, none of which are likely to make you happy:

  • Increase timeout value of the proxy (if it's under your control)
  • Make your request to a different server (if there's another server with the same data)
  • Make your request differently (if possible) such that you are requesting less data at a time
  • Try again once the server is not having issues

Function pointer as parameter

The correct way to do this is:

typedef void (*callback_function)(void); // type for conciseness

callback_function disconnectFunc; // variable to store function pointer type

void D::setDisconnectFunc(callback_function pFunc)
{
    disconnectFunc = pFunc; // store
}

void D::disconnected()
{
    disconnectFunc(); // call
    connected = false;
}

Installation failed with message Invalid File

  1. Invalidate cache/restart
  2. Clean Project
  3. Rebuild Project
  4. Run your app / Build APK

These steps are enough to solve most of the problems related to Gradle build in any way. These steps helped me solve this problem too.

Node.js: Difference between req.query[] and req.params

I want to mention one important note regarding req.query , because currently I am working on pagination functionality based on req.query and I have one interesting example to demonstrate to you...

Example:

// Fetching patients from the database
exports.getPatients = (req, res, next) => {

const pageSize = +req.query.pageSize;
const currentPage = +req.query.currentPage;

const patientQuery = Patient.find();
let fetchedPatients;

// If pageSize and currentPage are not undefined (if they are both set and contain valid values)
if(pageSize && currentPage) {
    /**
     * Construct two different queries 
     * - Fetch all patients 
     * - Adjusted one to only fetch a selected slice of patients for a given page
     */
    patientQuery
        /**
         * This means I will not retrieve all patients I find, but I will skip the first "n" patients
         * For example, if I am on page 2, then I want to skip all patients that were displayed on page 1,
         * 
         * Another example: if I am displaying 7 patients per page , I want to skip 7 items because I am on page 2,
         * so I want to skip (7 * (2 - 1)) => 7 items
         */
        .skip(pageSize * (currentPage - 1))

        /**
         * Narrow dont the amound documents I retreive for the current page
         * Limits the amount of returned documents
         * 
         * For example: If I got 7 items per page, then I want to limit the query to only
         * return 7 items. 
         */
        .limit(pageSize);
}
patientQuery.then(documents => {
    res.status(200).json({
        message: 'Patients fetched successfully',
        patients: documents
    });
  });
};

You will noticed + sign in front of req.query.pageSize and req.query.currentPage

Why? If you delete + in this case, you will get an error, and that error will be thrown because we will use invalid type (with error message 'limit' field must be numeric).

Important: By default if you extracting something from these query parameters, it will always be a string, because it's coming the URL and it's treated as a text.

If we need to work with numbers, and convert query statements from text to number, we can simply add a plus sign in front of statement.

Clicking a button within a form causes page refresh

Add action to your form.

<form action="#">

how to remove key+value from hash in javascript

You're looking for delete:

delete myhash['key2']

See the Core Javascript Guide

How do files get into the External Dependencies in Visual Studio C++?

The External Dependencies folder is populated by IntelliSense: the contents of the folder do not affect the build at all (you can in fact disable the folder in the UI).

You need to actually include the header (using a #include directive) to use it. Depending on what that header is, you may also need to add its containing folder to the "Additional Include Directories" property and you may need to add additional libraries and library folders to the linker options; you can set all of these in the project properties (right click the project, select Properties). You should compare the properties with those of the project that does build to determine what you need to add.

How to split a string at the first `/` (slash) and surround part of it in a `<span>`?

var str = "How are you doing today?";

var res = str.split(" ");

Here the variable "res" is kind of array.

You can also take this explicity by declaring it as

var res[]= str.split(" ");

Now you can access the individual words of the array. Suppose you want to access the third element of the array you can use it by indexing array elements.

var FirstElement= res[0];

Now the variable FirstElement contains the value 'How'

PowerShell: Store Entire Text File Contents in Variable

On a side note, in PowerShell 3.0 you can use the Get-Content cmdlet with the new Raw switch:

$text = Get-Content .\file.txt -Raw 

How do you add a Dictionary of items into another Dictionary

How about

dict2.forEach { (k,v) in dict1[k] = v }

That adds all of dict2's keys and values into dict1.

How to change a <select> value from JavaScript

You can use the selectedIndex property to set it to the first option:

document.getElementById("select").selectedIndex = 0;

Use of Custom Data Types in VBA

It looks like you want to define Truck as a Class with properties NumberOfAxles, AxleWeights & AxleSpacings.

This can be defined in a CLASS MODULE (here named clsTrucks)

Option Explicit

Private tID As String
Private tNumberOfAxles As Double
Private tAxleSpacings As Double


Public Property Get truckID() As String
    truckID = tID
End Property

Public Property Let truckID(value As String)
    tID = value
End Property

Public Property Get truckNumberOfAxles() As Double
    truckNumberOfAxles = tNumberOfAxles
End Property

Public Property Let truckNumberOfAxles(value As Double)
    tNumberOfAxles = value
End Property

Public Property Get truckAxleSpacings() As Double
    truckAxleSpacings = tAxleSpacings
End Property

Public Property Let truckAxleSpacings(value As Double)
    tAxleSpacings = value
End Property

then in a MODULE the following defines a new truck and it's properties and adds it to a collection of trucks and then retrieves the collection.

Option Explicit

Public TruckCollection As New Collection

Sub DefineNewTruck()
Dim tempTruck As clsTrucks
Dim i As Long

    'Add 5 trucks
    For i = 1 To 5
        Set tempTruck = New clsTrucks
        'Random data
        tempTruck.truckID = "Truck" & i
        tempTruck.truckAxleSpacings = 13.5 + i
        tempTruck.truckNumberOfAxles = 20.5 + i

        'tempTruck.truckID is the collection key
        TruckCollection.Add tempTruck, tempTruck.truckID
    Next i

    'retrieve 5 trucks
    For i = 1 To 5
        'retrieve by collection index
        Debug.Print TruckCollection(i).truckAxleSpacings
        'retrieve by key
        Debug.Print TruckCollection("Truck" & i).truckAxleSpacings

    Next i

End Sub

There are several ways of doing this so it really depends on how you intend to use the data as to whether an a class/collection is the best setup or arrays/dictionaries etc.

How to resize array in C++?

You cannot do that, see this question's answers. You may use std:vector instead.

In Oracle SQL: How do you insert the current date + time into a table?

You may try with below query :

INSERT INTO errortable (dateupdated,table1id)
VALUES (to_date(to_char(sysdate,'dd/mon/yyyy hh24:mi:ss'), 'dd/mm/yyyy hh24:mi:ss' ),1083 );

To view the result of it:

SELECT to_char(hire_dateupdated, 'dd/mm/yyyy hh24:mi:ss') 
FROM errortable 
    WHERE table1id = 1083;

Sorting using Comparator- Descending order (User defined classes)

Using Google Collections:

class Person {
 private int age;

 public static Function<Person, Integer> GET_AGE =
  new Function<Person, Integer> {
   public Integer apply(Person p) { return p.age; }
  };

}

public static void main(String[] args) {
 ArrayList<Person> people;
 // Populate the list...

 Collections.sort(people, Ordering.natural().onResultOf(Person.GET_AGE).reverse());
}

How can I plot with 2 different y-axes?

If you can give up the scales/axis labels, you can rescale the data to (0, 1) interval. This works for example for different 'wiggle' trakcs on chromosomes, when you're generally interested in local correlations between the tracks and they have different scales (coverage in thousands, Fst 0-1).

# rescale numeric vector into (0, 1) interval
# clip everything outside the range 
rescale <- function(vec, lims=range(vec), clip=c(0, 1)) {
  # find the coeficients of transforming linear equation
  # that maps the lims range to (0, 1)
  slope <- (1 - 0) / (lims[2] - lims[1])
  intercept <- - slope * lims[1]

  xformed <- slope * vec + intercept

  # do the clipping
  xformed[xformed < 0] <- clip[1]
  xformed[xformed > 1] <- clip[2]

  xformed
}

Then, having a data frame with chrom, position, coverage and fst columns, you can do something like:

ggplot(d, aes(position)) + 
  geom_line(aes(y = rescale(fst))) + 
  geom_line(aes(y = rescale(coverage))) +
  facet_wrap(~chrom)

The advantage of this is that you're not limited to two trakcs.

How do I get my C# program to sleep for 50 msec?

Since now you have async/await feature, the best way to sleep for 50ms is by using Task.Delay:

async void foo()
{
    // something
    await Task.Delay(50);
}

Or if you are targeting .NET 4 (with Async CTP 3 for VS2010 or Microsoft.Bcl.Async), you must use:

async void foo()
{
    // something
    await TaskEx.Delay(50);
}

This way you won't block UI thread.

Dynamically updating css in Angular 2

The accepted answer is not incorrect.

For grouped styles one can also use the ngStyle directive.

<some-element [ngStyle]="{'font-style': styleExpression, 'font-weight': 12}">...</some-element>

The official docs are here

Bootstrap 3 Navbar Collapse

I wanted to upvote and comment on jmbertucci's answer, but I'm not yet to be trusted with the controls. I had the same issue and resolved it as he said. If you are using Bootstrap 3.0, edit the LESS variables in variables.less The responsive break points are set around line 200:

@screen-xs:                  480px;
@screen-phone:               @screen-xs;

// Small screen / tablet
@screen-sm:                  768px;
@screen-tablet:              @screen-sm;

// Medium screen / desktop
@screen-md:                  992px;
@screen-desktop:             @screen-md;

// Large screen / wide desktop
@screen-lg:                  1200px;
@screen-lg-desktop:          @screen-lg;

// So media queries don't overlap when required, provide a maximum
@screen-xs-max:              (@screen-sm - 1);
@screen-sm-max:              (@screen-md - 1);
@screen-md-max:              (@screen-lg - 1);

Then set the collapse value for the navbar using the @grid-float-breakpoint variable at about line 232. By default it's set to @screen-tablet . If you want you can use a pixel value, but I prefer to use the LESS variables.

How to get .pem file from .key and .crt files?

A pem file contains the certificate and the private key. It depends on the format your certificate/key are in, but probably it's as simple as this:

cat server.crt server.key > server.pem

Run jQuery function onclick

There's several things you can improve upon here. To start, there's no reason to use an <a> (anchor) tag since you don't have a link.

Every element can be bound to click and hover events... divs, spans, labels, inputs, etc.

I can't really identify what it is you're trying to do, though. You're mixing the goal with your own implementation and, from what I've seen so far, you're not really sure how to do it. Could you better illustrate what it is you're trying to accomplish?

== EDIT ==

The requirements are still very vague. I've implemented a very quick version of what I'm imagining you're saying ... or something close that illustrates how you might be able to do it. Left me know if I'm on the right track.

http://jsfiddle.net/THEtheChad/j9Ump/

MySQL date format DD/MM/YYYY select query?

ORDER BY a date type does not depend on the date format, the date format is only for showing, in the database, they are same data.

How do you make sure email you send programmatically is not automatically marked as spam?

I would add :

Provide real unsubscription upon click on "Unsubscribe". I've seen real newsletters providing a dummy unsubscription link that upon click shows " has been unsubscribed successfully" but I will still receive further newsletters.

Node.js: get path from the request

simply call req.url. that should do the work. you'll get something like /something?bla=foo