Programs & Examples On #Mysql4

Using ALTER to drop a column if it exists in MySQL

I know this is an old thread, but there is a simple way to handle this requirement without using stored procedures. This may help someone.

set @exist_Check := (
    select count(*) from information_schema.columns 
    where TABLE_NAME='YOUR_TABLE' 
    and COLUMN_NAME='YOUR_COLUMN' 
    and TABLE_SCHEMA=database()
) ;
set @sqlstmt := if(@exist_Check>0,'alter table YOUR_TABLE drop column YOUR_COLUMN', 'select ''''') ;
prepare stmt from @sqlstmt ;
execute stmt ;

Hope this helps someone, as it did me (after a lot of trial and error).

Jquery date picker z-index issue

worked for me

.hasDatepicker {
    position: relative;
    z-index: 9999;
}

Check if PHP session has already started

@ before a function call suppresses any errors that may be reported during the function call.

Adding a @ before session_start tells PHP to avoid printing error messages.

For example:

Using session_start() after you've already printed something to the browser results in an error so PHP will display something like "headers cannot be sent: started at (line 12)", @session_start() will still fail in this case, but the error message is not printed on screen.

Before including the files or redirecting to new page use the exit() function, otherwise it will give an error.

This code can be used in all cases:


    <?php 
        if (session_status() !== PHP_SESSION_ACTIVE || session_id() === ""){
            session_start(); 
        }
    ?>

jQuery: read text file from file system

Something like this is what I use all the time. No need for any base64 decoding.

<html>
<head>
<script>
      window.onload = function(event) {
        document.getElementById('fileInput').addEventListener('change', handleFileSelect, false);
      }

      function handleFileSelect(event) {
        var fileReader = new FileReader();
        fileReader.onload = function(event) {
          $('#accessKeyField').val(event.target.result);
        }
        var file = event.target.files[0];
        fileReader.readAsText(file);
        document.getElementById('fileInput').value = null;
      }
</script>
</head>
<body>
<input type="file" id="fileInput" style="height: 20px; width: 100px;">
</body>
</html>

Plot inline or a separate window using Matplotlib in Spyder IDE

Magic commands such as

%matplotlib qt  

work in the iPython console and Notebook, but do not work within a script.

In that case, after importing:

from IPython import get_ipython

use:

get_ipython().run_line_magic('matplotlib', 'inline')

for inline plotting of the following code, and

get_ipython().run_line_magic('matplotlib', 'qt')

for plotting in an external window.

Edit: solution above does not always work, depending on your OS/Spyder version Anaconda issue on GitHub. Setting the Graphics Backend to Automatic (as indicated in another answer: Tools >> Preferences >> IPython console >> Graphics --> Automatic) solves the problem for me.

Then, after a Console restart, one can switch between Inline and External plot windows using the get_ipython() command, without having to restart the console.

MySQL date formats - difficulty Inserting a date

Put the date in single quotes and move the parenthesis (after the 'yes') to the end:

INSERT INTO custorder 
  VALUES ('Kevin', 'yes' , STR_TO_DATE('1-01-2012', '%d-%m-%Y') ) ;
                        ^                                     ^
---parenthesis removed--|                and added here ------|

But you can always use dates without STR_TO_DATE() function, just use the (Y-m-d) '20120101' or '2012-01-01' format. Check the MySQL docs: Date and Time Literals

INSERT INTO custorder 
  VALUES ('Kevin', 'yes', '2012-01-01') ;

Is it possible to read from a InputStream with a timeout?

Here is a way to get a NIO FileChannel from System.in and check for availability of data using a timeout, which is a special case of the problem described in the question. Run it at the console, don't type any input, and wait for the results. It was tested successfully under Java 6 on Windows and Linux.

import java.io.FileInputStream;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.reflect.Field;
import java.nio.ByteBuffer;
import java.nio.channels.ClosedByInterruptException;

public class Main {

    static final ByteBuffer buf = ByteBuffer.allocate(4096);

    public static void main(String[] args) {

        long timeout = 1000 * 5;

        try {
            InputStream in = extract(System.in);
            if (! (in instanceof FileInputStream))
                throw new RuntimeException(
                        "Could not extract a FileInputStream from STDIN.");

            try {
                int ret = maybeAvailable((FileInputStream)in, timeout);
                System.out.println(
                        Integer.toString(ret) + " bytes were read.");

            } finally {
                in.close();
            }

        } catch (Exception e) {
            throw new RuntimeException(e);
        }

    }

    /* unravels all layers of FilterInputStream wrappers to get to the
     * core InputStream
     */
    public static InputStream extract(InputStream in)
            throws NoSuchFieldException, IllegalAccessException {

        Field f = FilterInputStream.class.getDeclaredField("in");
        f.setAccessible(true);

        while( in instanceof FilterInputStream )
            in = (InputStream)f.get((FilterInputStream)in);

        return in;
    }

    /* Returns the number of bytes which could be read from the stream,
     * timing out after the specified number of milliseconds.
     * Returns 0 on timeout (because no bytes could be read)
     * and -1 for end of stream.
     */
    public static int maybeAvailable(final FileInputStream in, long timeout)
            throws IOException, InterruptedException {

        final int[] dataReady = {0};
        final IOException[] maybeException = {null};
        final Thread reader = new Thread() {
            public void run() {                
                try {
                    dataReady[0] = in.getChannel().read(buf);
                } catch (ClosedByInterruptException e) {
                    System.err.println("Reader interrupted.");
                } catch (IOException e) {
                    maybeException[0] = e;
                }
            }
        };

        Thread interruptor = new Thread() {
            public void run() {
                reader.interrupt();
            }
        };

        reader.start();
        for(;;) {

            reader.join(timeout);
            if (!reader.isAlive())
                break;

            interruptor.start();
            interruptor.join(1000);
            reader.join(1000);
            if (!reader.isAlive())
                break;

            System.err.println("We're hung");
            System.exit(1);
        }

        if ( maybeException[0] != null )
            throw maybeException[0];

        return dataReady[0];
    }
}

Interestingly, when running the program inside NetBeans 6.5 rather than at the console, the timeout doesn't work at all, and the call to System.exit() is actually necessary to kill the zombie threads. What happens is that the interruptor thread blocks (!) on the call to reader.interrupt(). Another test program (not shown here) additionally tries to close the channel, but that doesn't work either.

Printing without newline (print 'a',) prints a space, how to remove?

Just as a side note:

Printing is O(1) but building a string and then printing is O(n), where n is the total number of characters in the string. So yes, while building the string is "cleaner", it's not the most efficient method of doing so.

The way I would do it is as follows:

from sys import stdout
printf = stdout.write

Now you have a "print function" that prints out any string you give it without returning the new line character each time.

printf("Hello,")
printf("World!")

The output will be: Hello, World!

However, if you want to print integers, floats, or other non-string values, you'll have to convert them to a string with the str() function.

printf(str(2) + " " + str(4))

The output will be: 2 4

a tag as a submit button?

in my opinion the easiest way would be somthing like this:

<?php>
echo '<a href="link.php?submit='.$value.'">Submit</a>';
</?>

within the "link.php" you can request the value like this:

$_REQUEST['submit']

How do I insert a drop-down menu for a simple Windows Forms app in Visual Studio 2008?

You can use a ComboBox with its ComboBoxStyle (appears as DropDownStyle in later versions) set to DropDownList. See: http://msdn.microsoft.com/en-us/library/system.windows.forms.comboboxstyle.aspx

How to display the first few characters of a string in Python?

Since there is a delimiter, you should use that instead of worrying about how long the md5 is.

>>> s = "416d76b8811b0ddae2fdad8f4721ddbe|d4f656ee006e248f2f3a8a93a8aec5868788b927|12a5f648928f8e0b5376d2cc07de8e4cbf9f7ccbadb97d898373f85f0a75c47f"
>>> md5sum, delim, rest = s.partition('|')
>>> md5sum
'416d76b8811b0ddae2fdad8f4721ddbe'

Alternatively

>>> md5sum, sha1sum, sha5sum = s.split('|')
>>> md5sum
'416d76b8811b0ddae2fdad8f4721ddbe'
>>> sha1sum
'd4f656ee006e248f2f3a8a93a8aec5868788b927'
>>> sha5sum
'12a5f648928f8e0b5376d2cc07de8e4cbf9f7ccbadb97d898373f85f0a75c47f'

What should be the values of GOPATH and GOROOT?

GOPATH is discussed here:

The GOPATH Environment Variable

GOPATH may be set to a colon-separated list of paths inside which Go code, package objects, and executables may be found.

Set a GOPATH to use goinstall to build and install your own code and external libraries outside of the Go tree (and to avoid writing Makefiles).

And GOROOT is discussed here:

$GOROOT The root of the Go tree, often $HOME/go. This defaults to the parent of the directory where all.bash is run. If you choose not to set $GOROOT, you must run gomake instead of make or gmake when developing Go programs using the conventional makefiles.

How to delete multiple rows in SQL where id = (x to y)

CREATE PROC [dbo].[sp_DELETE_MULTI_ROW]       
@CODE XML
,@ERRFLAG  CHAR(1) = '0' OUTPUT    

AS        

SET NOCOUNT ON  
SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED  

DELETE tb_SampleTest
    WHERE 
        CODE IN(
            SELECT Item.value('.', 'VARCHAR(20)')
            FROM  @CODE.nodes('RecordList/ID') AS x(Item)
            )

IF @@ROWCOUNT = 0
    SET @ERRFLAG = 200

SET NOCOUNT OFF

Get string value delete

<RecordList>
    <ID>1</ID>
    <ID>2</ID>
</RecordList>

Stop executing further code in Java

To stop executing java code just use this command:

    System.exit(1);

After this command java stops immediately!

for example:

    int i = 5;
    if (i == 5) {
       System.out.println("All is fine...java programm executes without problem");
    } else {
       System.out.println("ERROR occured :::: java programm has stopped!!!");
       System.exit(1);
    }

PowerShell Remoting giving "Access is Denied" error

Had similar problems recently. Would suggest you carefully check if the user you're connecting with has proper authorizations on the remote machine.

You can review permissions using the following command.

Set-PSSessionConfiguration -ShowSecurityDescriptorUI -Name Microsoft.PowerShell

Found this tip here (updated link, thanks "unbob"):

https://devblogs.microsoft.com/scripting/configure-remote-security-settings-for-windows-powershell/

It fixed it for me.

Get DOS path instead of Windows path

A someone more direct answer is to fix the bug.

%SPARK_HOME%\bin\spark-class2.cmd; Line 54
Broken: set RUNNER="%JAVA_HOME%\bin\java"
Windows Style: set "RUNNER=%JAVA_HOME%\bin\java"

Otherwise, the RUNNER ends up with quotes, and the command "%RUNNER%" -Xmx128m ... ends up with double-quotes. The result is that the Program and File are treated as separate parameters.

Matplotlib figure facecolor (background color)

If you want to change background color, try this:

plt.rcParams['figure.facecolor'] = 'white'

Using env variable in Spring Boot's application.properties

You don't need to use java variables. To include system env variables add the following to your application.properties file:

spring.datasource.url = ${OPENSHIFT_MYSQL_DB_HOST}:${OPENSHIFT_MYSQL_DB_PORT}/"nameofDB"
spring.datasource.username = ${OPENSHIFT_MYSQL_DB_USERNAME}
spring.datasource.password = ${OPENSHIFT_MYSQL_DB_PASSWORD}

But the way suggested by @Stefan Isele is more preferable, because in this case you have to declare just one env variable: spring.profiles.active. Spring will read the appropriate property file automatically by application-{profile-name}.properties template.

Cannot insert explicit value for identity column in table 'table' when IDENTITY_INSERT is set to OFF

There are basically 2 different ways to INSERT records without having an error:

1) When the IDENTITY_INSERT is set OFF. The PRIMARY KEY "ID" MUST NOT BE PRESENT

2) When the IDENTITY_INSERT is set ON. The PRIMARY KEY "ID" MUST BE PRESENT

As per the following example from the same Table created with an IDENTITY PRIMARY KEY:

CREATE TABLE [dbo].[Persons] (    
    ID INT IDENTITY(1,1) PRIMARY KEY,
    LastName VARCHAR(40) NOT NULL,
    FirstName VARCHAR(40)
);

1) In the first example, you can insert new records into the table without getting an error when the IDENTITY_INSERT is OFF. The PRIMARY KEY "ID" MUST NOT BE PRESENT from the "INSERT INTO" Statements and a unique ID value will be added automatically:. If the ID is present from the INSERT in this case, you will get the error "Cannot insert explicit value for identify column in table..."

SET IDENTITY_INSERT [dbo].[Persons] OFF;
INSERT INTO [dbo].[Persons] (FirstName,LastName)
VALUES ('JANE','DOE'); 
INSERT INTO Persons (FirstName,LastName) 
VALUES ('JOE','BROWN');

OUTPUT of TABLE [dbo].[Persons] will be:

ID    LastName   FirstName
1     DOE        Jane
2     BROWN      JOE

2) In the Second example, you can insert new records into the table without getting an error when the IDENTITY_INSERT is ON. The PRIMARY KEY "ID" MUST BE PRESENT from the "INSERT INTO" Statements as long as the ID value does not already exist: If the ID is NOT present from the INSERT in this case, you will get the error "Explicit value must be specified for identity column table..."

SET IDENTITY_INSERT [dbo].[Persons] ON;
INSERT INTO [dbo].[Persons] (ID,FirstName,LastName)
VALUES (5,'JOHN','WHITE'); 
INSERT INTO [dbo].[Persons] (ID,FirstName,LastName)
VALUES (3,'JACK','BLACK'); 

OUTPUT of TABLE [dbo].[Persons] will be:

ID    LastName   FirstName
1     DOE        Jane
2     BROWN      JOE
3     BLACK      JACK
5     WHITE      JOHN

extract digits in a simple way from a python string

The simplest way to extract a number from a string is to use regular expressions and findall.

>>> import re
>>> s = '300 gm'
>>> re.findall('\d+', s)
['300']
>>> s = '300 gm 200 kgm some more stuff a number: 439843'
>>> re.findall('\d+', s)
['300', '200', '439843']

It might be that you need something more complex, but this is a good first step.

Note that you'll still have to call int on the result to get a proper numeric type (rather than another string):

>>> map(int, re.findall('\d+', s))
[300, 200, 439843]

Set the text in a span

You need to fix your selector. Although CSS syntax requires multiple classes to be space separated, selector syntax would require them to be directly concatenated, and dot prefixed:

$(".ui-icon.ui-icon-circle-triangle-w").text(...);

or better:

$(".ui-datepicker-prev > span").text(...);

add column to mysql table if it does not exist

If you are on MariaDB, no need to use stored procedures. Just use, for example:

ALTER TABLE table_name ADD COLUMN IF NOT EXISTS column_name tinyint(1) DEFAULT 0;

See here

Regular expression to get a string between two strings in Javascript

I was able to get what I needed using Martinho Fernandes' solution below. The code is:

var test = "My cow always gives milk";

var testRE = test.match("cow(.*)milk");
alert(testRE[1]);

You'll notice that I am alerting the testRE variable as an array. This is because testRE is returning as an array, for some reason. The output from:

My cow always gives milk

Changes into:

always gives

How do I clone into a non-empty directory?

This worked for me:

git init
git remote add origin PATH/TO/REPO
git fetch
git reset origin/master  # Required when the versioned files existed in path before "git init" of this repo.
git checkout -t origin/master

NOTE: -t will set the upstream branch for you, if that is what you want, and it usually is.

Java: Multiple class declarations in one file

According to Effective Java 2nd edition (Item 13):

"If a package-private top-level class (or interface) is used by only one class, consider making the top-level class a private nested class of the sole class that uses it (Item 22). This reduces its accessibility from all the classes in its package to the one class that uses it. But it is far more important to reduce the accessibility of a gratuitously public class than a package-private top-level class: ... "

The nested class may be static or non-static based on whether the member class needs access to the enclosing instance (Item 22).

How to get the focused element with jQuery?

$( document.activeElement )

Will retrieve it without having to search the whole DOM tree as recommended on the jQuery documentation

Remove Primary Key in MySQL

"if you restore the primary key, you sure may revert it back to AUTO_INCREMENT"

There should be no question of whether or not it is desirable to "restore the PK property" and "restore the autoincrement property" of the ID column.

Given that it WAS an autoincrement in the prior definition of the table, it is quite likely that there exists some program that inserts into this table without providing an ID value (because the ID column is autoincrement anyway).

Any such program's operation will break by not restoring the autoincrement property.

What is middleware exactly?

If I am not wrong, in software application framework, based on the context, you can consider middleware for the following roles that can be combined in order to perform certain activities in between the user request and the application response.

  • Adapter
  • Sanitizer
  • Validator

How to save picture to iPhone photo library?

Just pass the images from an array to it like so

-(void) saveMePlease {

//Loop through the array here
for (int i=0:i<[arrayOfPhotos count]:i++){
         NSString *file = [arrayOfPhotos objectAtIndex:i];
         NSString *path = [get the path of the image like you would in DOCS FOLDER or whatever];
         NSString *imagePath = [path stringByAppendingString:file];
         UIImage *image = [[[UIImage alloc] initWithContentsOfFile:imagePath]autorelease];

         //Now it will do this for each photo in the array
         UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
        }
}

Sorry for typo's kinda just did this on the fly but you get the point

How to set default value to all keys of a dict object in python?

defaultdict can do something like that for you.

Example:

>>> from collections import defaultdict
>>> d = defaultdict(list)
>>> d
defaultdict(<class 'list'>, {})
>>> d['new'].append(10)
>>> d
defaultdict(<class 'list'>, {'new': [10]})

How to auto adjust table td width from the content

Remove all widths set using CSS and set white-space to nowrap like so:

.content-loader tr td {
    white-space: nowrap;
}

I would also remove the fixed width from the container (or add overflow-x: scroll to the container) if you want the fields to display in their entirety without it looking odd...

See more here: http://www.w3schools.com/cssref/pr_text_white-space.asp

Docker official registry (Docker Hub) URL

The registry path for official images (without a slash in the name) is library/<image>. Try this instead:

docker pull registry.hub.docker.com/library/busybox

How can I quickly delete a line in VIM starting at the cursor position?

You might also be interested in C, it will also delete the end of line like D, but additionally it will put you in Insert mode at the cursor location.

how to customize `show processlist` in mysql?

If you use old version of MySQL you can always use \P combined with some nice piece of awk code. Interesting example here

http://www.dbasquare.com/2012/03/28/how-to-work-with-a-long-process-list-in-mysql/

Isn't it exactly what you need?

Recommended way to save uploaded files in a servlet application

I post my final way of doing it based on the accepted answer:

@SuppressWarnings("serial")
@WebServlet("/")
@MultipartConfig
public final class DataCollectionServlet extends Controller {

    private static final String UPLOAD_LOCATION_PROPERTY_KEY="upload.location";
    private String uploadsDirName;

    @Override
    public void init() throws ServletException {
        super.init();
        uploadsDirName = property(UPLOAD_LOCATION_PROPERTY_KEY);
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // ...
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        Collection<Part> parts = req.getParts();
        for (Part part : parts) {
            File save = new File(uploadsDirName, getFilename(part) + "_"
                + System.currentTimeMillis());
            final String absolutePath = save.getAbsolutePath();
            log.debug(absolutePath);
            part.write(absolutePath);
            sc.getRequestDispatcher(DATA_COLLECTION_JSP).forward(req, resp);
        }
    }

    // helpers
    private static String getFilename(Part part) {
        // courtesy of BalusC : http://stackoverflow.com/a/2424824/281545
        for (String cd : part.getHeader("content-disposition").split(";")) {
            if (cd.trim().startsWith("filename")) {
                String filename = cd.substring(cd.indexOf('=') + 1).trim()
                        .replace("\"", "");
                return filename.substring(filename.lastIndexOf('/') + 1)
                        .substring(filename.lastIndexOf('\\') + 1); // MSIE fix.
            }
        }
        return null;
    }
}

where :

@SuppressWarnings("serial")
class Controller extends HttpServlet {

    static final String DATA_COLLECTION_JSP="/WEB-INF/jsp/data_collection.jsp";
    static ServletContext sc;
    Logger log;
    // private
    // "/WEB-INF/app.properties" also works...
    private static final String PROPERTIES_PATH = "WEB-INF/app.properties";
    private Properties properties;

    @Override
    public void init() throws ServletException {
        super.init();
        // synchronize !
        if (sc == null) sc = getServletContext();
        log = LoggerFactory.getLogger(this.getClass());
        try {
            loadProperties();
        } catch (IOException e) {
            throw new RuntimeException("Can't load properties file", e);
        }
    }

    private void loadProperties() throws IOException {
        try(InputStream is= sc.getResourceAsStream(PROPERTIES_PATH)) {
                if (is == null)
                    throw new RuntimeException("Can't locate properties file");
                properties = new Properties();
                properties.load(is);
        }
    }

    String property(final String key) {
        return properties.getProperty(key);
    }
}

and the /WEB-INF/app.properties :

upload.location=C:/_/

HTH and if you find a bug let me know

Regular expression to match characters at beginning of line only

Regex symbol to match at beginning of a line:

^

Add the string you're searching for (CTR) to the regex like this:

^CTR

Example: regex

That should be enough!

However, if you need to get the text from the whole line in your language of choice, add a "match anything" pattern .*:

^CTR.*

Example: more regex

If you want to get crazy, use the end of line matcher

$

Add that to the growing regex pattern:

^CTR.*$

Example: lets get crazy

Note: Depending on how and where you're using regex, you might have to use a multi-line modifier to get it to match multiple lines. There could be a whole discussion on the best strategy for picking lines out of a file to process them, and some of the strategies would require this:

Multi-line flag m (this is specified in various ways in various languages/contexts)

/^CTR.*/gm

Example: we had to use m on regex101

Shorthand for if-else statement

?: Operator

If you want to shorten If/Else you can use ?: operator as:

condition ? action-on-true : action-on-false(else)

For instance:

let gender = isMale ? 'Male' : 'Female';

In this case else part is mandatory.

&& Operator

In another case, if you have only if condition you can use && operator as:

condition && action;

For instance:

!this.settings && (this.settings = new TableSettings());

FYI: You have to try to avoid using if-else or at least decrease using it and try to replace it with Polymorphism or Inheritance. Go for being Anti-If guy.

How to merge two arrays of objects by ID using lodash?

If both arrays are in the correct order; where each item corresponds to its associated member identifier then you can simply use.

var merge = _.merge(arr1, arr2);

Which is the short version of:

var merge = _.chain(arr1).zip(arr2).map(function(item) {
    return _.merge.apply(null, item);
}).value();

Or, if the data in the arrays is not in any particular order, you can look up the associated item by the member value.

var merge = _.map(arr1, function(item) {
    return _.merge(item, _.find(arr2, { 'member' : item.member }));
});

You can easily convert this to a mixin. See the example below:

_x000D_
_x000D_
_.mixin({_x000D_
  'mergeByKey' : function(arr1, arr2, key) {_x000D_
    var criteria = {};_x000D_
    criteria[key] = null;_x000D_
    return _.map(arr1, function(item) {_x000D_
      criteria[key] = item[key];_x000D_
      return _.merge(item, _.find(arr2, criteria));_x000D_
    });_x000D_
  }_x000D_
});_x000D_
_x000D_
var arr1 = [{_x000D_
  "member": 'ObjectId("57989cbe54cf5d2ce83ff9d6")',_x000D_
  "bank": 'ObjectId("575b052ca6f66a5732749ecc")',_x000D_
  "country": 'ObjectId("575b0523a6f66a5732749ecb")'_x000D_
}, {_x000D_
  "member": 'ObjectId("57989cbe54cf5d2ce83ff9d8")',_x000D_
  "bank": 'ObjectId("575b052ca6f66a5732749ecc")',_x000D_
  "country": 'ObjectId("575b0523a6f66a5732749ecb")'_x000D_
}];_x000D_
_x000D_
var arr2 = [{_x000D_
  "member": 'ObjectId("57989cbe54cf5d2ce83ff9d8")',_x000D_
  "name": 'yyyyyyyyyy',_x000D_
  "age": 26_x000D_
}, {_x000D_
  "member": 'ObjectId("57989cbe54cf5d2ce83ff9d6")',_x000D_
  "name": 'xxxxxx',_x000D_
  "age": 25_x000D_
}];_x000D_
_x000D_
var arr3 = _.mergeByKey(arr1, arr2, 'member');_x000D_
_x000D_
document.body.innerHTML = JSON.stringify(arr3, null, 4);
_x000D_
body { font-family: monospace; white-space: pre; }
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.14.0/lodash.min.js"></script>
_x000D_
_x000D_
_x000D_

how to sort order of LEFT JOIN in SQL query?

Older MySQL versions this is enough:

SELECT
    `userName`,
    `carPrice`
FROM `users`
LEFT JOIN (SELECT * FROM `cars` ORDER BY `carPrice`) as `cars`
ON cars.belongsToUser=users.id
WHERE `id`='4'

Nowdays, if you use MariaDB the subquery should be limited.

SELECT
    `userName`,
    `carPrice`
FROM `users`
LEFT JOIN (SELECT * FROM `cars` ORDER BY `carPrice` LIMIT 18446744073709551615) as `cars`
ON cars.belongsToUser=users.id
WHERE `id`='4'

I forgot the password I entered during postgres installation

  1. Edit the file /etc/postgresql/<version>/main/pg_hba.conf and find the following line:

    local   all             postgres                                md5
    
  2. Edit the line and change md5 at the end to trust and save the file

  3. Reload the postgresql service

    $ sudo service postgresql reload
    
  4. This will load the configuration files. Now you can modify the postgres user by logging into the psql shell

    $ psql -U postgres
    
  5. Update the postgres user's password

    alter user postgres with password 'secure-passwd-here';
    
  6. Edit the file /etc/postgresql/<version>/main/pg_hba.conf and change trust back to md5 and save the file

  7. Reload the postgresql service

    $ sudo service postgresql reload
    
  8. Verify that the password change is working

    $ psql -U postgres -W
    

Reading NFC Tags with iPhone 6 / iOS 8

I think it will be sometime before we get to see access to the NFC as the pure security side of it like for example being able to walk past somebody brush past them and & get your phone to the zap the card details or simply Wave your phone over someone's wallet which They left on the desk.

I think the first step is for Apple to talk to banks and find more ways of securing cards and NFC before This will be allowed

Use getElementById on HTMLElement instead of HTMLDocument

Sub Scrape()
    Dim Browser As InternetExplorer
    Dim Document As htmlDocument
    Dim Elements As IHTMLElementCollection
    Dim Element As IHTMLElement

    Set Browser = New InternetExplorer
    Browser.Visible = True
    Browser.navigate "http://www.stackoverflow.com"

    Do While Browser.Busy And Not Browser.readyState = READYSTATE_COMPLETE
        DoEvents
    Loop

    Set Document = Browser.Document

    Set Elements = Document.getElementById("hmenus").getElementsByTagName("li")
    For Each Element In Elements
        Debug.Print Element.innerText
        'Questions
        'Tags
        'Users
        'Badges
        'Unanswered
        'Ask Question
    Next Element

    Set Document = Nothing
    Set Browser = Nothing
End Sub

How can I convert spaces to tabs in Vim or Linux?

To use Vim to retab a set of files (e.g. all the *.ts files in a directory hierarchy) from say 2 spaces to 4 spaces you can try this from the command line:

find . -name '*.ts' -print0 | xargs -0 -n1 vim -e '+set ts=2 noet | retab! | set ts=4 et | retab | wq'

What this is doing is using find to pass all the matching files to xargs (the -print0 option on find works with the -0 option to xargs in order to handle files w/ spaces in the name).

xargs runs vim in ex mode (-e) on each file executing the given ex command which is actually several commands, to change the existing leading spaces to tabs, resetting the tab stop and changing the tabs back to spaces and finally saving and exiting.

Running in ex mode prevents this: Vim: Warning: Input is not from a terminal for each file.

Selecting multiple classes with jQuery

This should work:

$('.myClass, .myOtherClass').removeClass('theclass');

You must add the multiple selectors all in the first argument to $(), otherwise you are giving jQuery a context in which to search, which is not what you want.

It's the same as you would do in CSS.

Counting the number of option tags in a select tag in jQuery

In a multi-select option box, you can use $('#input1 :selected').length; to get the number of selected options. This can be useful to disable buttons if a certain minimum number of options aren't met.

function refreshButtons () {
    if ($('#input :selected').length == 0)
    {
        $('#submit').attr ('disabled', 'disabled');
    }
    else
    {
        $('#submit').removeAttr ('disabled');
    }
}

Group By Eloquent ORM

Eloquent uses the query builder internally, so you can do:

$users = User::orderBy('name', 'desc')
                ->groupBy('count')
                ->having('count', '>', 100)
                ->get();

How to list files using dos commands?

If you just want to get the file names and not directory names then use :

dir /b /a-d > file.txt

Rails Model find where not equal

Rails 4

GroupUser.where.not(user_id: me)

Error: Uncaught SyntaxError: Unexpected token <

If you face this issue only in Chrome and in IE, for instance, everything is fine, then just enable checkbutton "Disable cache" in Dev Tools (F12 -> "Network" tab) and clear history in the last hour.

I had this problem and above solution worked for me.

How to convert std::chrono::time_point to calendar datetime string with fractional seconds?

This worked for me for a format like YYYY.MM.DD-HH.MM.SS.fff. Attempting to make this code capable of accepting any string format will be like reinventing the wheel (i.e. there are functions for all this in Boost.

std::chrono::system_clock::time_point string_to_time_point(const std::string &str)
{
    using namespace std;
    using namespace std::chrono;

    int yyyy, mm, dd, HH, MM, SS, fff;

    char scanf_format[] = "%4d.%2d.%2d-%2d.%2d.%2d.%3d";

    sscanf(str.c_str(), scanf_format, &yyyy, &mm, &dd, &HH, &MM, &SS, &fff);

    tm ttm = tm();
    ttm.tm_year = yyyy - 1900; // Year since 1900
    ttm.tm_mon = mm - 1; // Month since January 
    ttm.tm_mday = dd; // Day of the month [1-31]
    ttm.tm_hour = HH; // Hour of the day [00-23]
    ttm.tm_min = MM;
    ttm.tm_sec = SS;

    time_t ttime_t = mktime(&ttm);

    system_clock::time_point time_point_result = std::chrono::system_clock::from_time_t(ttime_t);

    time_point_result += std::chrono::milliseconds(fff);
    return time_point_result;
}

std::string time_point_to_string(std::chrono::system_clock::time_point &tp)
{
    using namespace std;
    using namespace std::chrono;

    auto ttime_t = system_clock::to_time_t(tp);
    auto tp_sec = system_clock::from_time_t(ttime_t);
    milliseconds ms = duration_cast<milliseconds>(tp - tp_sec);

    std::tm * ttm = localtime(&ttime_t);

    char date_time_format[] = "%Y.%m.%d-%H.%M.%S";

    char time_str[] = "yyyy.mm.dd.HH-MM.SS.fff";

    strftime(time_str, strlen(time_str), date_time_format, ttm);

    string result(time_str);
    result.append(".");
    result.append(to_string(ms.count()));

    return result;
}

How to SELECT a dropdown list item by value programmatically

I prefer

if(ddl.Items.FindByValue(string) != null)
{
    ddl.Items.FindByValue(string).Selected = true;
}

Replace ddl with the dropdownlist ID and string with your string variable name or value.

Random number in range [min - max] using PHP

rand(1,20)

Docs for PHP's rand function are here:

http://php.net/manual/en/function.rand.php

Use the srand() function to set the random number generator's seed value.

Moment get current date

Just call moment as a function without any arguments:

moment()

For timezone information with moment, look at the moment-timezone package: http://momentjs.com/timezone/

What is the purpose of Looper and how to use it?

Life span of java Thread is over after completion of run() method. Same thread can't be started again.

Looper transforms normal Thread into a message loop. Key methods of Looper are :

void prepare ()

Initialize the current thread as a looper. This gives you a chance to create handlers that then reference this looper, before actually starting the loop. Be sure to call loop() after calling this method, and end it by calling quit().

void loop ()

Run the message queue in this thread. Be sure to call quit() to end the loop.

void quit()

Quits the looper.

Causes the loop() method to terminate without processing any more messages in the message queue.

This mindorks article by Janishar explains the core concepts in nice way.

enter image description here

Looper is associated with a Thread. If you need Looper on UI thread, Looper.getMainLooper() will return associated thread.

You need Looper to be associated with a Handler.

Looper, Handler, and HandlerThread are the Android’s way of solving the problems of asynchronous programming.

Once you have Handler, you can call below APIs.

post (Runnable r)

Causes the Runnable r to be added to the message queue. The runnable will be run on the thread to which this handler is attached.

boolean sendMessage (Message msg)

Pushes a message onto the end of the message queue after all pending messages before the current time. It will be received in handleMessage(Message), in the thread attached to this handler.

HandlerThread is handy class for starting a new thread that has a looper. The looper can then be used to create handler classes

In some scenarios, you can't run Runnable tasks on UI Thread. e.g. Network operations : Send message on a socket, open an URL and get content by reading InputStream

In these cases, HandlerThread is useful. You can get Looper object from HandlerThread and create a Handler on HandlerThread instead of main thread.

The HandlerThread code will be like this:

@Override
public void run() {
    mTid = Process.myTid();
    Looper.prepare();
    synchronized (this) {
        mLooper = Looper.myLooper();
        notifyAll();
    }
    Process.setThreadPriority(mPriority);
    onLooperPrepared();
    Looper.loop();
    mTid = -1;
}

Refer to below post for example code:

Android: Toast in a thread

Unit testing with mockito for constructors

I believe, it is not possible to mock constructors using mockito. Instead, I suggest following approach

Class First {

   private Second second;

   public First(int num, String str) {
     if(second== null)
     {
       //when junit runs, you get the mocked object(not null), hence don't 
       //initialize            
       second = new Second(str);
     }
     this.num = num;
   }

   ... // some other methods
}

And, for test:

class TestFirst{
    @InjectMock
    First first;//inject mock the real testable class
    @Mock
    Second second

    testMethod(){

        //now you can play around with any method of the Second class using its 
        //mocked object(second),like:
        when(second.getSomething(String.class)).thenReturn(null);
    }
}

Mvn install or Mvn package

If you're not using a remote repository (like artifactory), use plain old: mvn clean install

Pretty old topic but AFAIK, if you run your own repository (eg: with artifactory) to share jar among your team(s), you might want to use

mvn clean deploy

instead.

This way, your continuous integration server can be sure that all dependencies are correctly pushed into your remote repository. If you missed one, mvn will not be able to find it into your CI local m2 repository.

How to access share folder in virtualbox. Host Win7, Guest Fedora 16?

May be this can help other guys: I had the same problem, and after looking with Google I found that can be because of the permissions of the folder... So, you need first to add permissions...

$ chmod 777 share_folder

Then run again

$ sudo mount -t vboxsf D:\share_folder_vm \share_folder

Check the answers here: Error mounting VirtualBox shared folders in an Ubuntu guest...

ASP.NET DateTime Picker

@Html.EditorFor(model => model.Date, new { htmlAttributes = new { @class = "form-control", @type = "date" } })

this works well

Arduino Sketch upload issue - avrdude: stk500_recv(): programmer is not responding

I tried to connect my servo to the Arduino 5V pin, but the processor and that is why I got this failure

avrdude: stk500_recv(): programmer is not responding

Solution: buy a new Arduino and external 5 V power supply for the servo.

Server Discovery And Monitoring engine is deprecated

if you used typescript add config to the MongoOptions

const MongoOptions: MongoClientOptions = {
  useNewUrlParser: true,
  useUnifiedTopology: true,
};

      const client = await MongoClient.connect(url, MongoOptions);

if you not used typescript  
const MongoOptions= {
  useNewUrlParser: true,
  useUnifiedTopology: true,
};

How to completely uninstall python 2.7.13 on Ubuntu 16.04

try following to see all instances of python

whereis python
which python

Then remove all instances using:

sudo apt autoremove python

repeat sudo apt autoremove python(for all versions) that should do it, then install Anaconda and manage Pythons however you like if you need to reinstall it.

How to modify WooCommerce cart, checkout pages (main theme portion)

You can use function: wc_get_page_id( 'cart' ) to get the ID of the page. This function will use the page setup as 'cart' page and not the slug. Meaning it will keep working also when you setup a different url for your 'cart' on the settings page. This works for all kind of Woocommerce special page, like 'checkout', 'shop' etc.

example:

if (wc_get_page_id( 'cart' ) == get_the_ID()) {
  // Do something.
}

remove duplicates from sql union

Using UNION automatically removes duplicate rows unless you specify UNION ALL: http://msdn.microsoft.com/en-us/library/ms180026(SQL.90).aspx

GIT_DISCOVERY_ACROSS_FILESYSTEM problem when working with terminal and MacFusion

Try a different protocol. git:// may have problems from your firewall, for example; try a git clone with https: instead.

What is the best/simplest way to read in an XML file in Java application?

Is there a particular reason you have chosen XML config files? I have done XML configs in the past, and they have often turned out to be more of a headache than anything else.

I guess the real question is whether using something like the Preferences API might work better in your situation.

Reasons to use the Preferences API over a roll-your-own XML solution:

  • Avoids typical XML ugliness (DocumentFactory, etc), along with avoiding 3rd party libraries to provide the XML backend

  • Built in support for default values (no special handling required for missing/corrupt/invalid entries)

  • No need to sanitize values for XML storage (CDATA wrapping, etc)

  • Guaranteed status of the backing store (no need to constantly write XML out to disk)

  • Backing store is configurable (file on disk, LDAP, etc.)

  • Multi-threaded access to all preferences for free

dplyr mutate with conditional values

With dplyr 0.7.2, you can use the very useful case_when function :

x=read.table(
 text="V1 V2 V3 V4
 1  1  2  3  5
 2  2  4  4  1
 3  1  4  1  1
 4  4  5  1  3
 5  5  5  5  4")
x$V5 = case_when(x$V1==1 & x$V2!=4 ~ 1,
                 x$V2==4 & x$V3!=1 ~ 2,
                 TRUE ~ 0)

Expressed with dplyr::mutate, it gives:

x = x %>% mutate(
     V5 = case_when(
         V1==1 & V2!=4 ~ 1,
         V2==4 & V3!=1 ~ 2,
         TRUE ~ 0
     )
)

Please note that NA are not treated specially, as it can be misleading. The function will return NA only when no condition is matched. If you put a line with TRUE ~ ..., like I did in my example, the return value will then never be NA.

Therefore, you have to expressively tell case_when to put NA where it belongs by adding a statement like is.na(x$V1) | is.na(x$V3) ~ NA_integer_. Hint: the dplyr::coalesce() function can be really useful here sometimes!

Moreover, please note that NA alone will usually not work, you have to put special NA values : NA_integer_, NA_character_ or NA_real_.

set up device for development (???????????? no permissions)

Without unplugging

All the provided answers assume that you are able to unplug and reconnect the USB cable. In situations where this is not possible (e.g., when you are remote), you can do the following to essentially do what the suggested udev rules would do on re-plug:

lsusb

Find the device you care about, e.g.:

Bus 003 Device 005: ID 18d1:4ee4 Google Inc. Nexus

Take note of the bus number it is on and then execute, e.g. for bus 003:

sudo chmod a+w /dev/bus/usb/003/*

Clearly this may be more permissive than you want (there may be more devices attached than just this one), but you get the idea.

What is the use of ObservableCollection in .net?

One of the biggest uses is that you can bind UI components to one, and they'll respond appropriately if the collection's contents change. For example, if you bind a ListView's ItemsSource to one, the ListView's contents will automatically update if you modify the collection.

EDIT: Here's some sample code from MSDN: http://msdn.microsoft.com/en-us/library/ms748365.aspx

In C#, hooking the ListBox to the collection could be as easy as

listBox.ItemsSource = NameListData;

though if you haven't hooked the list up as a static resource and defined NameItemTemplate you may want to override PersonName's ToString(). For example:

public override ToString()
{
    return string.Format("{0} {1}", this.FirstName, this.LastName);
}

What are the differences between struct and class in C++?

**UPDATE: ** Please ignore this reply. I did not consider the possibility that for the struct, the value was uninitialized but just happened to be 0. There is not an initialization difference between struct and class.


I am seeing another different between structs and classes having to do with default initialization.

struct Foo {
    int a;
};

class Bar {
    int a;
};

class Tester {
    Foo m_Foo = Foo();
    Bar m_Bar = Bar();

public:
    Tester() {}
};

int main() {
    auto myTester = Tester();
}

Run that code and examine myTester. You'll find that for m_Foo, the struct, m_Foo.a has been initialized to 0, but for m_Bar, the class, m_Bar.a is uninitialized. So there does appear to be a difference in what the default constructor does for struct vs. class. I'm seeing this with Visual Studio.

JavaScript + Unicode regexes

Situation for ES 6

The upcoming ECMAScript language specification, edition 6, includes Unicode-aware regular expressions. Support must be enabled with the u modifier on the regex. See Unicode-aware regular expressions in ES6.

Until ES 6 is finished and widely adopted among browser vendors you're still on your own, though. Update: There is now a transpiler named regexpu that translates ES6 Unicode regular expressions into equivalent ES5. It can be used as part of your build process. Try it out online.

Situation for ES 5 and below

Even though JavaScript operates on Unicode strings, it does not implement Unicode-aware character classes and has no concept of POSIX character classes or Unicode blocks/sub-ranges.

isset PHP isset($_GET['something']) ? $_GET['something'] : ''

? is called Ternary (conditional) operator : example

How to set up Android emulator proxy settings

This will not help for the browser, but you can also define a proxy in your code to use with a HTTP client:

// proxy
private static final String PROXY = "123.123.123.123";
// proxy host
private static final HttpHost PROXY_HOST = new HttpHost(PROXY, 8080);
HttpParams httpParameters = new BasicHttpParams();
DefaultHttpClient httpClient = new DefaultHttpClient(httpParameters);
httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, PROXY_HOST);

Calling stored procedure with return value

The version of EnterpriseLibrary on my machine had other parameters. This was working:

        SqlParameter retval = new SqlParameter("@ReturnValue", System.Data.SqlDbType.Int);
        retval.Direction = System.Data.ParameterDirection.ReturnValue;
        cmd.Parameters.Add(retval);
        db.ExecuteNonQuery(cmd);
        object o = cmd.Parameters["@ReturnValue"].Value;

How to create a new file in unix?

The command is lowercase: touch filename.

Keep in mind that touch will only create a new file if it does not exist! Here's some docs for good measure: http://unixhelp.ed.ac.uk/CGI/man-cgi?touch

If you always want an empty file, one way to do so would be to use:

echo "" > filename

How to break line in JavaScript?

Here you are ;-)

<script type="text/javascript">
    alert("Hello there.\nI am on a second line ;-)")
</script>

Setting environment variable in react-native?

Step 1: Create separate component like this Component name : pagebase.js
Step 2: Inside this use code this

    export const BASE_URL = "http://192.168.10.10:4848/";
    export const API_KEY = 'key_token';

Step 3: Use it in any component, for using it first import this component then use it. Import it and use it:

        import * as base from "./pagebase";

        base.BASE_URL
        base.API_KEY

VB.NET - If string contains "value1" or "value2"

I've approached this in a different way. I've created a function which simply returns true or false.. Usage:

If FieldContains("A;B;C",MyFieldVariable,True|False) then

.. Do Something

End If

Public Function FieldContains(Searchfor As String, SearchField As String, AllowNulls As Boolean) As Boolean

       If AllowNulls And Len(SearchField) = 0 Then Return True

        For Each strSearchFor As String In Searchfor.Split(";")
            If UCase(SearchField) = UCase(strSearchFor) Then
                Return True
            End If
        Next

        Return False

    End Function

How to implement a queue using two stacks?

You can even simulate a queue using only one stack. The second (temporary) stack can be simulated by the call stack of recursive calls to the insert method.

The principle stays the same when inserting a new element into the queue:

  • You need to transfer elements from one stack to another temporary stack, to reverse their order.
  • Then push the new element to be inserted, onto the temporary stack
  • Then transfer the elements back to the original stack
  • The new element will be on the bottom of the stack, and the oldest element is on top (first to be popped)

A Queue class using only one Stack, would be as follows:

public class SimulatedQueue<E> {
    private java.util.Stack<E> stack = new java.util.Stack<E>();

    public void insert(E elem) {
        if (!stack.empty()) {
            E topElem = stack.pop();
            insert(elem);
            stack.push(topElem);
        }
        else
            stack.push(elem);
    }

    public E remove() {
        return stack.pop();
    }
}

How to write "Html.BeginForm" in Razor

The following code works fine:

@using (Html.BeginForm("Upload", "Upload", FormMethod.Post, 
                                      new { enctype = "multipart/form-data" }))
{
    @Html.ValidationSummary(true)
    <fieldset>
        Select a file <input type="file" name="file" />
        <input type="submit" value="Upload" />
    </fieldset>
}

and generates as expected:

<form action="/Upload/Upload" enctype="multipart/form-data" method="post">    
    <fieldset>
        Select a file <input type="file" name="file" />
        <input type="submit" value="Upload" />
    </fieldset>
</form>

On the other hand if you are writing this code inside the context of other server side construct such as an if or foreach you should remove the @ before the using. For example:

@if (SomeCondition)
{
    using (Html.BeginForm("Upload", "Upload", FormMethod.Post, 
                                      new { enctype = "multipart/form-data" }))
    {
        @Html.ValidationSummary(true)
        <fieldset>
            Select a file <input type="file" name="file" />
            <input type="submit" value="Upload" />
        </fieldset>
    }
}

As far as your server side code is concerned, here's how to proceed:

[HttpPost]
public ActionResult Upload(HttpPostedFileBase file) 
{
    if (file != null && file.ContentLength > 0) 
    {
        var fileName = Path.GetFileName(file.FileName);
        var path = Path.Combine(Server.MapPath("~/content/pics"), fileName);
        file.SaveAs(path);
    }
    return RedirectToAction("Upload");
}

Environment Variable with Maven

You could wrap your maven command in a bash script:

#!/bin/bash

export YOUR_VAR=thevalue
mvn test
unset YOUR_VAR

How to convert a datetime to string in T-SQL

This has been answered by a lot of people, but I feel like the simplest solution has been left out.

SQL SERVER (I believe its 2012+) has implicit string equivalents for DATETIME2 as shown here

Look at the section on "Supported string literal formats for datetime2"

To answer the OPs question explicitly:

DECLARE @myVar NCHAR(32)
DECLARE @myDt DATETIME2
SELECT @myVar = @GETDATE()
SELECT @myDt = @myVar
PRINT(@myVar)
PRINT(@myDt)

output:

Jan 23 2019 12:24PM             
2019-01-23 12:24:00.0000000

Note: The first variable (myVar) is actually holding the value '2019-01-23 12:24:00.0000000' as well. It just gets formatted to Jan 23 2019 12:24PM due to default formatting set for SQL SERVER that gets called on when you use PRINT. Don't get tripped up here by that, the actual string in (myVer) = '2019-01-23 12:24:00.0000000'

disable editing default value of text input

I'm not sure I understand the question correctly, but if you want to prevent people from writing in the input field you can use the disabled attribute.

<input disabled="disabled" id="price_from" value="price from ">

Check if argparse optional argument is set or not

If your argument is positional (ie it doesn't have a "-" or a "--" prefix, just the argument, typically a file name) then you can use the nargs parameter to do this:

parser = argparse.ArgumentParser(description='Foo is a program that does things')
parser.add_argument('filename', nargs='?')
args = parser.parse_args()

if args.filename is not None:
    print('The file name is {}'.format(args.filename))
else:
    print('Oh well ; No args, no problems')

Oracle SQL update based on subquery between two tables

Try it ..

UPDATE PRODUCTION a
SET (name, count) = (
SELECT name, count
        FROM STAGING b
        WHERE a.ID = b.ID)
WHERE EXISTS (SELECT 1
    FROM STAGING b
    WHERE a.ID=b.ID
 );

How to convert a Scikit-learn dataset to a Pandas dataset?

One of the best ways:

data = pd.DataFrame(digits.data)

Digits is the sklearn dataframe and I converted it to a pandas DataFrame

How to dispatch a Redux action with a timeout?

A repository with sample projects

Current there are four sample projects:

  1. Writing Async Code Inline
  2. Extracting Async Action Creator
  3. Use Redux Thunk
  4. Use Redux Saga

The accepted answer is awesome.

But there is something missing:

  1. No runnable sample projects, just some code snippets.
  2. No sample code for other alternatives, such as:
    1. Redux Saga

So I created the Hello Async repository to add the missing things:

  1. Runnable projects. You can download and run them without modification.
  2. Provide sample code for more alternatives:

Redux Saga

The accepted answer already provides sample code snippets for Async Code Inline, Async Action Generator and Redux Thunk. For the sake of completeness, I provide code snippets for Redux Saga:

// actions.js

export const showNotification = (id, text) => {
  return { type: 'SHOW_NOTIFICATION', id, text }
}

export const hideNotification = (id) => {
  return { type: 'HIDE_NOTIFICATION', id }
}

export const showNotificationWithTimeout = (text) => {
  return { type: 'SHOW_NOTIFICATION_WITH_TIMEOUT', text }
}

Actions are simple and pure.

// component.js

import { connect } from 'react-redux'

// ...

this.props.showNotificationWithTimeout('You just logged in.')

// ...

export default connect(
  mapStateToProps,
  { showNotificationWithTimeout }
)(MyComponent)

Nothing is special with component.

// sagas.js

import { takeEvery, delay } from 'redux-saga'
import { put } from 'redux-saga/effects'
import { showNotification, hideNotification } from './actions'

// Worker saga
let nextNotificationId = 0
function* showNotificationWithTimeout (action) {
  const id = nextNotificationId++
  yield put(showNotification(id, action.text))
  yield delay(5000)
  yield put(hideNotification(id))
}

// Watcher saga, will invoke worker saga above upon action 'SHOW_NOTIFICATION_WITH_TIMEOUT'
function* notificationSaga () {
  yield takeEvery('SHOW_NOTIFICATION_WITH_TIMEOUT', showNotificationWithTimeout)
}

export default notificationSaga

Sagas are based on ES6 Generators

// index.js

import createSagaMiddleware from 'redux-saga'
import saga from './sagas'

const sagaMiddleware = createSagaMiddleware()

const store = createStore(
  reducer,
  applyMiddleware(sagaMiddleware)
)

sagaMiddleware.run(saga)

Compared to Redux Thunk

Pros

  • You don't end up in callback hell.
  • You can test your asynchronous flows easily.
  • Your actions stay pure.

Cons

  • It depends on ES6 Generators which is relatively new.

Please refer to the runnable project if the code snippets above don't answer all of your questions.

Draw radius around a point in Google map

For a API v3 solution, refer to:

http://blog.enbake.com/draw-circle-with-google-maps-api-v3

It creates circle around points and then show markers within and out of the range with different colors. They also calculate dynamic radius but in your case radius is fixed so may be less work.

Matplotlib: ValueError: x and y must have same first dimension

You should make x and y numpy arrays, not lists:

x = np.array([0.46,0.59,0.68,0.99,0.39,0.31,1.09,
              0.77,0.72,0.49,0.55,0.62,0.58,0.88,0.78])
y = np.array([0.315,0.383,0.452,0.650,0.279,0.215,0.727,0.512,
              0.478,0.335,0.365,0.424,0.390,0.585,0.511])

With this change, it produces the expect plot. If they are lists, m * x will not produce the result you expect, but an empty list. Note that m is anumpy.float64 scalar, not a standard Python float.

I actually consider this a bit dubious behavior of Numpy. In normal Python, multiplying a list with an integer just repeats the list:

In [42]: 2 * [1, 2, 3]
Out[42]: [1, 2, 3, 1, 2, 3]

while multiplying a list with a float gives an error (as I think it should):

In [43]: 1.5 * [1, 2, 3]
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-43-d710bb467cdd> in <module>()
----> 1 1.5 * [1, 2, 3]
TypeError: can't multiply sequence by non-int of type 'float'

The weird thing is that multiplying a Python list with a Numpy scalar apparently works:

In [45]: np.float64(0.5) * [1, 2, 3]
Out[45]: []

In [46]: np.float64(1.5) * [1, 2, 3]
Out[46]: [1, 2, 3]

In [47]: np.float64(2.5) * [1, 2, 3]
Out[47]: [1, 2, 3, 1, 2, 3]

So it seems that the float gets truncated to an int, after which you get the standard Python behavior of repeating the list, which is quite unexpected behavior. The best thing would have been to raise an error (so that you would have spotted the problem yourself instead of having to ask your question on Stackoverflow) or to just show the expected element-wise multiplication (in which your code would have just worked). Interestingly, addition between a list and a Numpy scalar does work:

In [69]: np.float64(0.123) + [1, 2, 3]
Out[69]: array([ 1.123,  2.123,  3.123])

Excel CSV. file with more than 1,048,576 rows of data

You can try to download and install TheGun Text Editor. Which can help you to open large csv file easily.

You can check detailed article here https://developingdaily.com/article/how-to/what-is-csv-file-and-how-to-open-a-large-csv-file/82

Can I run Keras model on gpu?

Of course. if you are running on Tensorflow or CNTk backends, your code will run on your GPU devices defaultly.But if Theano backends, you can use following

Theano flags:

"THEANO_FLAGS=device=gpu,floatX=float32 python my_keras_script.py"

Pandas (python): How to add column to dataframe for index?

I stumbled on this question while trying to do the same thing (I think). Here is how I did it:

df['index_col'] = df.index

You can then sort on the new index column, if you like.

Laravel 5 Class 'form' not found

Begin by installing this package through Composer. Run the following from the terminal:

composer require "laravelcollective/html":"^5.3.0"

Next, add your new provider to the providers array of config/app.php:

'providers' => [
    // ...
    Collective\Html\HtmlServiceProvider::class,
    // ...
  ],

Finally, add two class aliases to the aliases array of config/app.php:

'aliases' => [
    // ...
      'Form' => Collective\Html\FormFacade::class,
      'Html' => Collective\Html\HtmlFacade::class,
    // ...
  ],

SRC:

https://laravelcollective.com/docs/5.3/html

git stash and git pull

When you have changes on your working copy, from command line do:

git stash 

This will stash your changes and clear your status report

git pull

This will pull changes from upstream branch. Make sure it says fast-forward in the report. If it doesn't, you are probably doing an unintended merge

git stash pop

This will apply stashed changes back to working copy and remove the changes from stash unless you have conflicts. In the case of conflict, they will stay in stash so you can start over if needed.

if you need to see what is in your stash

git stash list

MVC Redirect to View from jQuery with parameters

redirect with query string

 $('#results').on('click', '.item', function () {
                    var NestId = $(this).data('id');
                   // var url = '@Url.Action("Details", "Artists",new { NestId = '+NestId+'  })'; 
                    var url = '@ Url.Content("~/Artists/Details?NestId =' + NestId + '")'
                    window.location.href = url; 
                })

How to get the exact local time of client?

Here is a version that works well in September 2020 using fetch and https://worldtimeapi.org/api

_x000D_
_x000D_
fetch("https://worldtimeapi.org/api/ip")
  .then(response => response.json())
  .then(data => console.log(data.dst,data.datetime));
_x000D_
_x000D_
_x000D_

How to log as much information as possible for a Java Exception?

What's wrong with the printStacktrace() method provided by Throwable (and thus every exception)? It shows all the info you requested, including the type, message, and stack trace of the root exception and all (nested) causes. In Java 7, it even shows you the information about "supressed" exceptions that might occur in a try-with-resources statement.

Of course you wouldn't want to write to System.err, which the no-argument version of the method does, so instead use one of the available overloads.

In particular, if you just want to get a String:

  Exception e = ...
  StringWriter sw = new StringWriter();
  e.printStackTrace(new PrintWriter(sw));
  String exceptionDetails = sw.toString();

If you happen to use the great Guava library, it provides a utility method doing this: com.google.common.base.Throwables#getStackTraceAsString(Throwable).

How do I write the 'cd' command in a makefile?

It is actually executing the command, changing the directory to some_directory, however, this is performed in a sub-process shell, and affects neither make nor the shell you're working from.

If you're looking to perform more tasks within some_directory, you need to add a semi-colon and append the other commands as well. Note that you cannot use newlines as they are interpreted by make as the end of the rule, so any newlines you use for clarity needs to be escaped by a backslash.

For example:

all:
        cd some_dir; echo "I'm in some_dir"; \
          gcc -Wall -o myTest myTest.c

Note also that the semicolon is necessary between every command even though you add a backslash and a newline. This is due to the fact that the entire string is parsed as a single line by the shell. As noted in the comments, you should use '&&' to join commands, which mean they only get executed if the preceding command was successful.

all:
        cd some_dir && echo "I'm in some_dir" && \
          gcc -Wall -o myTest myTest.c

This is especially crucial when doing destructive work, such as clean-up, as you'll otherwise destroy the wrong stuff, should the cd fail for whatever reason.

A common usage though is to call make in the sub directory, which you might want to look into. There's a command line option for this so you don't have to call cd yourself, so your rule would look like this

all:
        $(MAKE) -C some_dir all

which will change into some_dir and execute the Makefile in there with the target "all". As a best practice, use $(MAKE) instead of calling make directly, as it'll take care to call the right make instance (if you, for example, use a special make version for your build environment), as well as provide slightly different behavior when running using certain switches, such as -t.

For the record, make always echos the command it executes (unless explicitly suppressed), even if it has no output, which is what you're seeing.

Is there a Max function in SQL Server that takes two values like Math.Max in .NET?

SELECT o.OrderId,   
--MAX(o.NegotiatedPrice, o.SuggestedPrice)  
(SELECT MAX(v) FROM (VALUES (o.NegotiatedPrice), (o.SuggestedPrice)) AS value(v)) as ChoosenPrice  
FROM Order o

How to prevent a click on a '#' link from jumping to top of page?

Links with href="#" should almost always be replaced with a button element:

<button class="someclass">Text</button>

Using links with href="#" is also an accessibility concern as these links will be visible to screen readers, which will read out "Link - Text" but if the user clicks it won't go anywhere.

Iterating over and deleting from Hashtable in Java

You can use Enumeration:

Hashtable<Integer, String> table = ...

Enumeration<Integer> enumKey = table.keys();
while(enumKey.hasMoreElements()) {
    Integer key = enumKey.nextElement();
    String val = table.get(key);
    if(key==0 && val.equals("0"))
        table.remove(key);
}

List vs tuple, when to use each?

Must it be mutable? Use a list. Must it not be mutable? Use a tuple.

Otherwise, it's a question of choice.

For collections of heterogeneous objects (like a address broken into name, street, city, state and zip) I prefer to use a tuple. They can always be easily promoted to named tuples.

Likewise, if the collection is going to be iterated over, I prefer a list. If it's just a container to hold multiple objects as one, I prefer a tuple.

"detached entity passed to persist error" with JPA/EJB code

I had this problem and it was caused by the second level cache:

  1. I persisted an entity using hibernate
  2. Then I deleted the row created from a separate process that didn't interact with the second level cache
  3. I persisted another entity with the same identifier (my identifier values are not auto-generated)

Hence, because the cache wasn't invalidated, hibernate assumed that it was dealing with a detached instance of the same entity.

how to execute a scp command with the user name and password in one line

Using sshpass works best. To just include your password in scp use the ' ':

scp user1:'password'@xxx.xxx.x.5:sys_config /var/www/dev/

How can I programmatically determine if my app is running in the iphone simulator?

Has anyone considered the answer provided here?

I suppose the objective-c equivalent would be

+ (BOOL)isSimulator {
    NSOperatingSystemVersion ios9 = {9, 0, 0};
    NSProcessInfo *processInfo = [NSProcessInfo processInfo];
    if ([processInfo isOperatingSystemAtLeastVersion:ios9]) {
        NSDictionary<NSString *, NSString *> *environment = [processInfo environment];
        NSString *simulator = [environment objectForKey:@"SIMULATOR_DEVICE_NAME"];
        return simulator != nil;
    } else {
        UIDevice *currentDevice = [UIDevice currentDevice];
        return ([currentDevice.model rangeOfString:@"Simulator"].location != NSNotFound);
    }
}

how to assign a block of html code to a javascript variable

Just for reference, here is a benchmark of different technique rendering performances,

http://jsperf.com/zp-string-concatenation/6

m,

$(this).attr("id") not working

I recommend you to read more about the this keyword.

You cannot expect "this" to select the "select" tag in this case.

What you want to do in this case is use obj.id to get the id of select tag.

Change the URL in the browser without loading the new page using JavaScript

There is a Yahoo YUI component (Browser History Manager) which can handle this: http://developer.yahoo.com/yui/history/

Python dict how to create key or append an element to key?

You can use a defaultdict for this.

from collections import defaultdict
d = defaultdict(list)
d['key'].append('mykey')

This is slightly more efficient than setdefault since you don't end up creating new lists that you don't end up using. Every call to setdefault is going to create a new list, even if the item already exists in the dictionary.

JavaScript Chart Library

It maybe not exactly what you are looking for, but
Google's Chart API is pretty cool and easy to use.

Where to find Java JDK Source Code?

Here the official link for jdk source. http://www.oracle.com/technetwork/java/javase/downloads/index.html (you may need to scroll to the bottom of the page)

Powershell Execute remote exe with command line arguments on remote computer

Are you trying to pass the command line arguments to the program AS you launch it? I am working on something right now that does exactly this, and it was a lot simpler than I thought. If I go into the command line, and type

C:\folder\app.exe/xC:\folder\file.txt

then my application launches, and creates a file in the specified directory with the specified name.

I wanted to do this through a Powershell script on a remote machine, and figured out that all I needed to do was put

$s = New-PSSession -computername NAME -credential LOGIN
    Invoke-Command -session $s -scriptblock {C:\folder\app.exe /xC:\folder\file.txt}
Remove-PSSession $s

(I have a bunch more similar commands inside the session, this is just the minimum it requires to run) notice the space between the executable, and the command line arguments. It works for me, but I am not sure exactly how your application works, or if that is even how you pass arguments to it.

*I can also have my application push the file back to my own local computer by changing the script-block to

C:\folder\app.exe /x"\\LocalPC\DATA (C)\localfolder\localfile.txt"

You need the quotes if your file-path has a space in it.

EDIT: actually, this brought up some silly problems with Powershell launching the application as a service or something, so I did some searching, and figured out that you can call CMD to execute commands for you on the remote computer. This way, the command is carried out EXACTLY as if you had just typed it into a CMD window on the remote machine. Put the command in the scriptblock into double quotes, and then put a cmd.exe /C before it. like this:

cmd.exe /C "C:\folder\app.exe/xC:\folder\file.txt"

this solved all of the problems that I have been having recently.

EDIT EDIT: Had more problems, and found a much better way to do it.

start-process -filepath C:\folder\app.exe -argumentlist "/xC:\folder\file.txt"

and this doesn't hang up your terminal window waiting for the remote process to end. Just make sure you have a way to terminate the process if it doesn't do that on it's own. (mine doesn't, required the coding of another argument)

Secure hash and salt for PHP passwords

DISCLAIMER: This answer was written in 2008.

Since then, PHP has given us password_hash and password_verify and, since their introduction, they are the recommended password hashing & checking method.

The theory of the answer is still a good read though.

TL;DR

Don'ts

  • Don't limit what characters users can enter for passwords. Only idiots do this.
  • Don't limit the length of a password. If your users want a sentence with supercalifragilisticexpialidocious in it, don't prevent them from using it.
  • Don't strip or escape HTML and special characters in the password.
  • Never store your user's password in plain-text.
  • Never email a password to your user except when they have lost theirs, and you sent a temporary one.
  • Never, ever log passwords in any manner.
  • Never hash passwords with SHA1 or MD5 or even SHA256! Modern crackers can exceed 60 and 180 billion hashes/second (respectively).
  • Don't mix bcrypt and with the raw output of hash(), either use hex output or base64_encode it. (This applies to any input that may have a rogue \0 in it, which can seriously weaken security.)

Dos

  • Use scrypt when you can; bcrypt if you cannot.
  • Use PBKDF2 if you cannot use either bcrypt or scrypt, with SHA2 hashes.
  • Reset everyone's passwords when the database is compromised.
  • Implement a reasonable 8-10 character minimum length, plus require at least 1 upper case letter, 1 lower case letter, a number, and a symbol. This will improve the entropy of the password, in turn making it harder to crack. (See the "What makes a good password?" section for some debate.)

Why hash passwords anyway?

The objective behind hashing passwords is simple: preventing malicious access to user accounts by compromising the database. So the goal of password hashing is to deter a hacker or cracker by costing them too much time or money to calculate the plain-text passwords. And time/cost are the best deterrents in your arsenal.

Another reason that you want a good, robust hash on a user accounts is to give you enough time to change all the passwords in the system. If your database is compromised you will need enough time to at least lock the system down, if not change every password in the database.

Jeremiah Grossman, CTO of Whitehat Security, stated on White Hat Security blog after a recent password recovery that required brute-force breaking of his password protection:

Interestingly, in living out this nightmare, I learned A LOT I didn’t know about password cracking, storage, and complexity. I’ve come to appreciate why password storage is ever so much more important than password complexity. If you don’t know how your password is stored, then all you really can depend upon is complexity. This might be common knowledge to password and crypto pros, but for the average InfoSec or Web Security expert, I highly doubt it.

(Emphasis mine.)

What makes a good password anyway?

Entropy. (Not that I fully subscribe to Randall's viewpoint.)

In short, entropy is how much variation is within the password. When a password is only lowercase roman letters, that's only 26 characters. That isn't much variation. Alpha-numeric passwords are better, with 36 characters. But allowing upper and lower case, with symbols, is roughly 96 characters. That's a lot better than just letters. One problem is, to make our passwords memorable we insert patterns—which reduces entropy. Oops!

Password entropy is approximated easily. Using the full range of ascii characters (roughly 96 typeable characters) yields an entropy of 6.6 per character, which at 8 characters for a password is still too low (52.679 bits of entropy) for future security. But the good news is: longer passwords, and passwords with unicode characters, really increase the entropy of a password and make it harder to crack.

There's a longer discussion of password entropy on the Crypto StackExchange site. A good Google search will also turn up a lot of results.

In the comments I talked with @popnoodles, who pointed out that enforcing a password policy of X length with X many letters, numbers, symbols, etc, can actually reduce entropy by making the password scheme more predictable. I do agree. Randomess, as truly random as possible, is always the safest but least memorable solution.

So far as I've been able to tell, making the world's best password is a Catch-22. Either its not memorable, too predictable, too short, too many unicode characters (hard to type on a Windows/Mobile device), too long, etc. No password is truly good enough for our purposes, so we must protect them as though they were in Fort Knox.

Best practices

Bcrypt and scrypt are the current best practices. Scrypt will be better than bcrypt in time, but it hasn't seen adoption as a standard by Linux/Unix or by webservers, and hasn't had in-depth reviews of its algorithm posted yet. But still, the future of the algorithm does look promising. If you are working with Ruby there is an scrypt gem that will help you out, and Node.js now has its own scrypt package. You can use Scrypt in PHP either via the Scrypt extension or the Libsodium extension (both are available in PECL).

I highly suggest reading the documentation for the crypt function if you want to understand how to use bcrypt, or finding yourself a good wrapper or use something like PHPASS for a more legacy implementation. I recommend a minimum of 12 rounds of bcrypt, if not 15 to 18.

I changed my mind about using bcrypt when I learned that bcrypt only uses blowfish's key schedule, with a variable cost mechanism. The latter lets you increase the cost to brute-force a password by increasing blowfish's already expensive key schedule.

Average practices

I almost can't imagine this situation anymore. PHPASS supports PHP 3.0.18 through 5.3, so it is usable on almost every installation imaginable—and should be used if you don't know for certain that your environment supports bcrypt.

But suppose that you cannot use bcrypt or PHPASS at all. What then?

Try an implementation of PDKBF2 with the maximum number of rounds that your environment/application/user-perception can tolerate. The lowest number I'd recommend is 2500 rounds. Also, make sure to use hash_hmac() if it is available to make the operation harder to reproduce.

Future Practices

Coming in PHP 5.5 is a full password protection library that abstracts away any pains of working with bcrypt. While most of us are stuck with PHP 5.2 and 5.3 in most common environments, especially shared hosts, @ircmaxell has built a compatibility layer for the coming API that is backward compatible to PHP 5.3.7.

Cryptography Recap & Disclaimer

The computational power required to actually crack a hashed password doesn't exist. The only way for computers to "crack" a password is to recreate it and simulate the hashing algorithm used to secure it. The speed of the hash is linearly related to its ability to be brute-forced. Worse still, most hash algorithms can be easily parallelized to perform even faster. This is why costly schemes like bcrypt and scrypt are so important.

You cannot possibly foresee all threats or avenues of attack, and so you must make your best effort to protect your users up front. If you do not, then you might even miss the fact that you were attacked until it's too late... and you're liable. To avoid that situation, act paranoid to begin with. Attack your own software (internally) and attempt to steal user credentials, or modify other user's accounts or access their data. If you don't test the security of your system, then you cannot blame anyone but yourself.

Lastly: I am not a cryptographer. Whatever I've said is my opinion, but I happen to think it's based on good ol' common sense ... and lots of reading. Remember, be as paranoid as possible, make things as hard to intrude as possible, and then, if you are still worried, contact a white-hat hacker or cryptographer to see what they say about your code/system.

Google Maps how to Show city or an Area outline

I have try twitter geo api, failed.

Google map api, failed, so far, no way you can get city limit by any api.

twitter api geo endpoint will NOT give you city boundary,

what they provide you is ONLY bounding box with 5 point(lat, long)

this is what I get from twitter api geo for San Francisco enter image description here

What is the best free memory leak detector for a C/C++ program and its plug-in DLLs?

I have had good experiences with Rational Purify. I have also heard nice things about Valgrind

Getting the names of all files in a directory with PHP

Don't bother with open/readdir and use glob instead:

foreach(glob($log_directory.'/*.*') as $file) {
    ...
}

Replace part of a string in Python?

>>> stuff = "Big and small"
>>> stuff.replace(" and ","/")
'Big/small'

How to make html <select> element look like "disabled", but pass values?

Wow, I had the same problem, but a line of code resolved my problem. I wrote

$last_child_topic.find( "*" ).prop( "disabled", true );
$last_child_topic.find( "option" ).prop( "disabled", false );   //This seems to work on mine

I send the form to a php script then it prints the correct value for each options while it was "null" before.

Tell me if this works out. I wonder if this only works on mine somehow.

MySQL OPTIMIZE all tables?

If you want to analyze, repair and optimize all tables in all databases in your MySQL server, you can do this in one go from the command line. You will need root to do that though.

mysqlcheck -u root -p --auto-repair --optimize --all-databases

Once you run that, you will be prompted to enter your MySQL root password. After that, it will start and you will see results as it's happening.

Example output:

yourdbname1.yourdbtable1       OK
yourdbname2.yourdbtable2       Table is already up to date
yourdbname3.yourdbtable3
note     : Table does not support optimize, doing recreate + analyze instead
status   : OK

etc..
etc...

Repairing tables
yourdbname10.yourdbtable10
warning  : Number of rows changed from 121378 to 81562
status   : OK

If you don't know the root password and are using WHM, you can change it from within WHM by going to: Home > SQL Services > MySQL Root Password

iOS 6 apps - how to deal with iPhone 5 screen size?

No.

if ([[UIScreen mainScreen] bounds].size.height > 960)

on iPhone 5 is wrong

if ([[UIScreen mainScreen] bounds].size.height == 568)

How to export non-exportable private key from store

You're right, no API at all that I'm aware to export PrivateKey marked as non-exportable. But if you patch (in memory) normal APIs, you can use the normal way to export :)

There is a new version of mimikatz that also support CNG Export (Windows Vista / 7 / 2008 ...)

  1. download (and launch with administrative privileges) : http://blog.gentilkiwi.com/mimikatz (trunk version or last version)

Run it and enter the following commands in its prompt:

  1. privilege::debug (unless you already have it or target only CryptoApi)
  2. crypto::patchcng (nt 6) and/or crypto::patchcapi (nt 5 & 6)
  3. crypto::exportCertificates and/or crypto::exportCertificates CERT_SYSTEM_STORE_LOCAL_MACHINE

The exported .pfx files are password protected with the password "mimikatz"

Finding what methods a Python object has

You can use the built in dir() function to get a list of all the attributes a module has. Try this at the command line to see how it works.

>>> import moduleName
>>> dir(moduleName)

Also, you can use the hasattr(module_name, "attr_name") function to find out if a module has a specific attribute.

See the Guide to Python introspection for more information.

Jquery Change Height based on Browser Size/Resize

Building on Chad's answer, you also want to add that function to the onload event to ensure it is resized when the page loads as well.

jQuery.event.add(window, "load", resizeFrame);
jQuery.event.add(window, "resize", resizeFrame);

function resizeFrame() 
{
    var h = $(window).height();
    var w = $(window).width();
    $("#elementToResize").css('height',(h < 768 || w < 1024) ? 500 : 400);
}

What does file:///android_asset/www/index.html mean?

it's file:///android_asset/... not file:///android_assets/... notice the plural of assets is wrong even if your file name is assets

Clear text area

Correct answer is: $("#selElement_Id option:selected").removeAttr("selected");

What does 'stale file handle' in Linux mean?

When the directory is deleted, the inode for that directory (and the inodes for its contents) are recycled. The pointer your shell has to that directory's inode (and its contents's inodes) are now no longer valid. When the directory is restored from backup, the old inodes are not (necessarily) reused; the directory and its contents are stored on random inodes. The only thing that stays the same is that the parent directory reuses the same name for the restored directory (because you told it to).

Now if you attempt to access the contents of the directory that your original shell is still pointing to, it communicates that request to the file system as a request for the original inode, which has since been recycled (and may even be in use for something entirely different now). So you get a stale file handle message because you asked for some nonexistent data.

When you perform a cd operation, the shell reevaluates the inode location of whatever destination you give it. Now that your shell knows the new inode for the directory (and the new inodes for its contents), future requests for its contents will be valid.

SQL Views - no variables?

You could use WITH to define your expressions. Then do a simple Sub-SELECT to access those definitions.

CREATE VIEW MyView
AS
  WITH MyVars (SomeVar, Var2)
  AS (
    SELECT
      'something' AS 'SomeVar',
      123 AS 'Var2'
  )

  SELECT *
  FROM MyTable
  WHERE x = (SELECT SomeVar FROM MyVars)

PostgreSQL: ERROR: operator does not exist: integer = character varying

I think it is telling you exactly what is wrong. You cannot compare an integer with a varchar. PostgreSQL is strict and does not do any magic typecasting for you. I'm guessing SQLServer does typecasting automagically (which is a bad thing).

If you want to compare these two different beasts, you will have to cast one to the other using the casting syntax ::.

Something along these lines:

create view view1
as 
select table1.col1,table2.col1,table3.col3
from table1 
inner join
table2 
inner join 
table3
on 
table1.col4::varchar = table2.col5
/* Here col4 of table1 is of "integer" type and col5 of table2 is of type "varchar" */
/* ERROR: operator does not exist: integer = character varying */
....;

Notice the varchar typecasting on the table1.col4.

Also note that typecasting might possibly render your index on that column unusable and has a performance penalty, which is pretty bad. An even better solution would be to see if you can permanently change one of the two column types to match the other one. Literately change your database design.

Or you could create a index on the casted values by using a custom, immutable function which casts the values on the column. But this too may prove suboptimal (but better than live casting).

Reading a string with scanf

An array "decays" into a pointer to its first element, so scanf("%s", string) is equivalent to scanf("%s", &string[0]). On the other hand, scanf("%s", &string) passes a pointer-to-char[256], but it points to the same place.

Then scanf, when processing the tail of its argument list, will try to pull out a char *. That's the Right Thing when you've passed in string or &string[0], but when you've passed in &string you're depending on something that the language standard doesn't guarantee, namely that the pointers &string and &string[0] -- pointers to objects of different types and sizes that start at the same place -- are represented the same way.

I don't believe I've ever encountered a system on which that doesn't work, and in practice you're probably safe. None the less, it's wrong, and it could fail on some platforms. (Hypothetical example: a "debugging" implementation that includes type information with every pointer. I think the C implementation on the Symbolics "Lisp Machines" did something like this.)

Proper way to return JSON using node or Express

You can make a helper for that: Make a helper function so that you can use it everywhere in your application

function getStandardResponse(status,message,data){
    return {
        status: status,
        message : message,
        data : data
     }
}

Here is my topic route where I am trying to get all topics

router.get('/', async (req, res) => {
    const topics = await Topic.find().sort('name');
    return res.json(getStandardResponse(true, "", topics));
});

Response we get

{
"status": true,
"message": "",
"data": [
    {
        "description": "sqswqswqs",
        "timestamp": "2019-11-29T12:46:21.633Z",
        "_id": "5de1131d8f7be5395080f7b9",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575031579309.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    },
    {
        "description": "sqswqswqs",
        "timestamp": "2019-11-29T12:50:35.627Z",
        "_id": "5de1141bc902041b58377218",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575031835605.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    },
    {
        "description": " ",
        "timestamp": "2019-11-30T06:51:18.936Z",
        "_id": "5de211665c3f2c26c00fe64f",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575096678917.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    },
    {
        "description": "null",
        "timestamp": "2019-11-30T06:51:41.060Z",
        "_id": "5de2117d5c3f2c26c00fe650",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575096701051.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    },
    {
        "description": "swqdwqd wwwwdwq",
        "timestamp": "2019-11-30T07:05:22.398Z",
        "_id": "5de214b2964be62d78358f87",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575097522372.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    },
    {
        "description": "swqdwqd wwwwdwq",
        "timestamp": "2019-11-30T07:36:48.894Z",
        "_id": "5de21c1006f2b81790276f6a",
        "name": "topics test xqxq",
        "thumbnail": "waterfall-or-agile-inforgraphics-thumbnail-1575099408870.jpg",
        "category_id": "5de0fe0b4f76c22ebce2b70a",
        "__v": 0
    }
      ]
}

Cancel a vanilla ECMAScript 6 Promise chain

Promise can be cancelled with the help of AbortController.

Is there a method for clearing then: yes you can reject the promise with AbortController object and then the promise will bypass all then blocks and go directly to the catch block.

Example:

import "abortcontroller-polyfill";

let controller = new window.AbortController();
let signal = controller.signal;
let elem = document.querySelector("#status")

let example = (signal) => {
    return new Promise((resolve, reject) => {
        let timeout = setTimeout(() => {
            elem.textContent = "Promise resolved";
            resolve("resolved")
        }, 2000);

        signal.addEventListener('abort', () => {
            elem.textContent = "Promise rejected";
            clearInterval(timeout);
            reject("Promise aborted")
        });
    });
}

function cancelPromise() {
    controller.abort()
    console.log(controller);
}

example(signal)
    .then(data => {
        console.log(data);
    })
    .catch(error => {
        console.log("Catch: ", error)
    });

document.getElementById('abort-btn').addEventListener('click', cancelPromise);

Html


    <button type="button" id="abort-btn" onclick="abort()">Abort</button>
    <div id="status"> </div>

Note: need to add polyfill, not supported in all browser.

Live Example

Edit elegant-lake-5jnh3

Eclipse error "ADB server didn't ACK, failed to start daemon"

ADB will often fail if there is a newline in adb_usb.ini. Remove it, restart it, and that will often solve the problem (at least for me anyway).

How to mention C:\Program Files in batchfile

I had a similar issue as you, although I was trying to use start to open Chrome and using the file path. I used only start chrome.exe and it opened just fine. You may want to try to do the same with exe file. Using the file path may be unnecessary.

Here are some examples (using the file name you gave in a comment on another answer):

  • Instead of C:\Program^ Files\temp.exe you can try temp.exe.

  • Instead of start C:\Program^ Files\temp.exe you can try start temp.exe

jquery $(window).height() is returning the document height

I had the same problem, and using this solved it.

var w = window.innerWidth;
var h = window.innerHeight;

I am receiving warning in Facebook Application using PHP SDK

You need to ensure that any code that modifies the HTTP headers is executed before the headers are sent. This includes statements like session_start(). The headers will be sent automatically when any HTML is output.

Your problem here is that you're sending the HTML ouput at the top of your page before you've executed any PHP at all.

Move the session_start() to the top of your document :

<?php    session_start(); ?> <html> <head> <title>PHP SDK</title> </head> <body> <?php require_once 'src/facebook.php';    // more PHP code here. 

How can I reset or revert a file to a specific revision?

You have to be careful when you say "rollback". If you used to have one version of a file in commit $A, and then later made two changes in two separate commits $B and $C (so what you are seeing is the third iteration of the file), and if you say "I want to roll back to the first one", do you really mean it?

If you want to get rid of the changes both the second and the third iteration, it is very simple:

$ git checkout $A file

and then you commit the result. The command asks "I want to check out the file from the state recorded by the commit $A".

On the other hand, what you meant is to get rid of the change the second iteration (i.e. commit $B) brought in, while keeping what commit $C did to the file, you would want to revert $B

$ git revert $B

Note that whoever created commit $B may not have been very disciplined and may have committed totally unrelated change in the same commit, and this revert may touch files other than file you see offending changes, so you may want to check the result carefully after doing so.

How to send Request payload to REST API in java?

The following code works for me.

//escape the double quotes in json string
String payload="{\"jsonrpc\":\"2.0\",\"method\":\"changeDetail\",\"params\":[{\"id\":11376}],\"id\":2}";
String requestUrl="https://git.eclipse.org/r/gerrit/rpc/ChangeDetailService";
sendPostRequest(requestUrl, payload);

method implementation:

public static String sendPostRequest(String requestUrl, String payload) {
    try {
        URL url = new URL(requestUrl);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();

        connection.setDoInput(true);
        connection.setDoOutput(true);
        connection.setRequestMethod("POST");
        connection.setRequestProperty("Accept", "application/json");
        connection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
        OutputStreamWriter writer = new OutputStreamWriter(connection.getOutputStream(), "UTF-8");
        writer.write(payload);
        writer.close();
        BufferedReader br = new BufferedReader(new InputStreamReader(connection.getInputStream()));
        StringBuffer jsonString = new StringBuffer();
        String line;
        while ((line = br.readLine()) != null) {
                jsonString.append(line);
        }
        br.close();
        connection.disconnect();
        return jsonString.toString();
    } catch (Exception e) {
            throw new RuntimeException(e.getMessage());
    }

}

Spring: how do I inject an HttpServletRequest into a request-scoped bean?

Spring exposes the current HttpServletRequest object (as well as the current HttpSession object) through a wrapper object of type ServletRequestAttributes. This wrapper object is bound to ThreadLocal and is obtained by calling the static method RequestContextHolder.currentRequestAttributes().

ServletRequestAttributes provides the method getRequest() to get the current request, getSession() to get the current session and other methods to get the attributes stored in both the scopes. The following code, though a bit ugly, should get you the current request object anywhere in the application:

HttpServletRequest curRequest = 
((ServletRequestAttributes) RequestContextHolder.currentRequestAttributes())
.getRequest();

Note that the RequestContextHolder.currentRequestAttributes() method returns an interface and needs to be typecasted to ServletRequestAttributes that implements the interface.


Spring Javadoc: RequestContextHolder | ServletRequestAttributes

How to add a ListView to a Column in Flutter?

You can use Flex and Flexible widgets. for example:

Flex(
direction: Axis.vertical,
children: <Widget>[
    ... other widgets ...
    Flexible(
        flex: 1,
        child: ListView.builder(
        itemCount: ...,
        itemBuilder: (context, index) {
            ...
        },
        ),
    ),
],

);

How to detect iPhone 5 (widescreen devices)?

this is the macro for my cocos2d project. should be the same for other apps.

#define WIDTH_IPAD 1024
#define WIDTH_IPHONE_5 568
#define WIDTH_IPHONE_4 480
#define HEIGHT_IPAD 768
#define HEIGHT_IPHONE 320

#define IS_IPHONE (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPhone)
#define IS_IPAD (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)

//width is height!
#define IS_IPHONE_5 ( [ [ UIScreen mainScreen ] bounds ].size.height == WIDTH_IPHONE_5 )
#define IS_IPHONE_4 ( [ [ UIScreen mainScreen ] bounds ].size.height == WIDTH_IPHONE_4 )

#define cp_ph4(__X__, __Y__) ccp(cx_ph4(__X__), cy_ph4(__Y__))
#define cx_ph4(__X__) (IS_IPAD ? (__X__ * WIDTH_IPAD / WIDTH_IPHONE_4) : (IS_IPHONE_5 ? (__X__ * WIDTH_IPHONE_5 / WIDTH_IPHONE_4) : (__X__)))
#define cy_ph4(__Y__) (IS_IPAD ? (__Y__ * HEIGHT_IPAD / HEIGHT_IPHONE) : (__Y__))

#define cp_pad(__X__, __Y__) ccp(cx_pad(__X__), cy_pad(__Y__))
#define cx_pad(__X__) (IS_IPAD ? (__X__) : (IS_IPHONE_5 ? (__X__ * WIDTH_IPHONE_5 / WIDTH_IPAD) : (__X__ * WIDTH_IPHONE_4 / WIDTH_IPAD)))
#define cy_pad(__Y__) (IS_IPAD ? (__Y__) : (__Y__ * HEIGHT_IPHONE / HEIGHT_IPAD))

jQuery - find table row containing table cell containing specific text

$(function(){
    var search = 'foo';
    $("table tr td").filter(function() {
        return $(this).text() == search;
    }).parent('tr').css('color','red');
});

Will turn the text red for rows which have a cell whose text is 'foo'.

Clicking a button within a form causes page refresh

I use directive to prevent default behaviour:

module.directive('preventDefault', function() {
    return function(scope, element, attrs) {
        angular.element(element).bind('click', function(event) {
            event.preventDefault();
            event.stopPropagation();
        });
    }
});

And then, in html:

<button class="secondaryButton" prevent-default>Secondary action</button>

This directive can also be used with <a> and all other tags

Tesseract OCR simple example

I had same problem, now its resolved. I have tesseract2, under this folders for 32 bit and 64 bit, I copied files 64 bit folder(as my system is 64 bit) to main folder ("Tesseract2") and under bin/Debug folder. Now my solution is working fine.

Ubuntu - Run command on start-up with "sudo"

Edit the tty configuration in /etc/init/tty*.conf with a shellscript as a parameter :

(...)
exec /sbin/getty -n -l  theInputScript.sh -8 38400 tty1
(...)

This is assuming that we're editing tty1 and the script that reads input is theInputScript.sh.

A word of warning this script is run as root, so when you are inputing stuff to it you have root priviliges. Also append a path to the location of the script.

Important: the script when it finishes, has to invoke the /sbin/login otherwise you wont be able to login in the terminal.

Intellij Idea: Importing Gradle project - getting JAVA_HOME not defined yet

For MacOS this worked for me without the need to hardcode a particular Java version:

launchctl setenv JAVA_HOME "$(jenv javahome)"

Is it possible to get only the first character of a String?

Here I am taking Mobile No From EditText It may start from +91 or 0 but i am getting actual 10 digits. Hope this will help you.

              String mob=edit_mobile.getText().toString();
                    if (mob.length() >= 10) {
                        if (mob.contains("+91")) {
                            mob= mob.substring(3, 13);
                        }
                        if (mob.substring(0, 1).contains("0")) {
                            mob= mob.substring(1, 11);
                        }
                        if (mob.contains("+")) {
                            mob= mob.replace("+", "");
                        }
                        mob= mob.substring(0, 10);
                        Log.i("mob", mob);

                    }

jQuery: count number of rows in a table

row_count =  $('#my_table').find('tr').length;
column_count =  $('#my_table').find('td').length / row_count;

LINQ equivalent of foreach for IEnumerable<T>

According to PLINQ (available since .Net 4.0), you can do an

IEnumerable<T>.AsParallel().ForAll() 

to do a parallel foreach loop on an IEnumerable.

How to use a variable inside a regular expression?

you can try another usage using format grammer suger:

re_genre = r'{}'.format(your_variable)
regex_pattern = re.compile(re_genre)  

How to list only top level directories in Python?

You could also use os.scandir:

with os.scandir(os.getcwd()) as mydir:
    dirs = [i.name for i in mydir if i.is_dir()]

In case you want the full path you can use i.path.

Using scandir() instead of listdir() can significantly increase the performance of code that also needs file type or file attribute information, because os.DirEntry objects expose this information if the operating system provides it when scanning a directory.

GUI Tool for PostgreSQL

There is a comprehensive list of tools on the PostgreSQL Wiki:

https://wiki.postgresql.org/wiki/PostgreSQL_Clients

And of course PostgreSQL itself comes with pgAdmin, a GUI tool for accessing Postgres databases.

Excel: last character/string match in a string

Very late to the party, but A simple solution is using VBA to create a custom function.

Add the function to VBA in the WorkBook, Worksheet, or a VBA Module

Function LastSegment(S, C)
    LastSegment = Right(S, Len(S) - InStrRev(S, C))
End Function

Then the cell formula

=lastsegment(B1,"/")

in a cell and the string to be searched in cell B1 will populate the cell with the text trailing the last "/" from cell B1. No length limit, no obscure formulas. Only downside I can think is the need for a macro-enabled workbook.

Any user VBA Function can be called this way to return a value to a cell formula, including as a parameter to a builtin Excel function.

If you are going to use the function heavily you'll want to check for the case when the character is not in the string, then string is blank, etc.

Can I connect to SQL Server using Windows Authentication from Java EE webapp?

Unless you have some really compelling reason not to, I suggest ditching the MS JDBC driver.

Instead, use the jtds jdbc driver. Read the README.SSO file in the jtds distribution on how to configure for single-sign-on (native authentication) and where to put the native DLL to ensure it can be loaded by the JVM.

Android: how to parse URL String with spaces to URI object?

To handle spaces, @, and other unsafe characters in arbitrary locations in the url path, Use Uri.Builder in combination with a local instance of URL as I have described here:

private Uri.Builder builder;
public Uri getUriFromUrl(String thisUrl) {
    URL url = new URL(thisUrl);
    builder =  new Uri.Builder()
                            .scheme(url.getProtocol())
                            .authority(url.getAuthority())
                            .appendPath(url.getPath());
    return builder.build();
}

Print empty line?

This is are other ways of printing empty lines in python

# using \n after the string creates an empty line after this string is passed to the the terminal.
print("We need to put about", average_passengers_per_car, "in each car. \n") 
print("\n") #prints 2 empty lines 
print() #prints 1 empty line 

How to change button color with tkinter

When you do self.button = Button(...).grid(...), what gets assigned to self.button is the result of the grid() command, not a reference to the Button object created.

You need to assign your self.button variable before packing/griding it. It should look something like this:

self.button = Button(self,text="Click Me",command=self.color_change,bg="blue")
self.button.grid(row = 2, column = 2, sticky = W)

PHP Warning: POST Content-Length of 8978294 bytes exceeds the limit of 8388608 bytes in Unknown on line 0

Using wamp do the following and hopefully, it will resolve an issue

Make these changes in PHP Options to correct:

max_execution_time   180

memory_limit   512M or your highest available

post_max_size  32M

upload_max_filesize   64M

Android: Changing Background-Color of the Activity (Main View)

First Method

 View someView = findViewById(R.id.randomViewInMainLayout);// get Any child View

  // Find the root view
  View root = someView.getRootView()

  // Set the color
  root.setBackgroundColor(getResources().getColor(android.R.color.red));

Second Method

Add this single line after setContentView(...);

getWindow().getDecorView().setBackgroundColor(Color.WHITE);

Third Method

set background color to the rootView

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#FFFFFF"
android:id="@+id/rootView"
</LinearLayout>

Important Thing

rootView.setBackgroundColor(0xFF00FF00); //after 0x the other four pairs are alpha,red,green,blue color. 

CSS: How to change colour of active navigation page menu

Add ID current for active/current page:

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

#current a { color: #ff0000; }

VBA check if file exists

Here is my updated code. Checks to see if version exists before saving and saves as the next available version number.

Sub SaveNewVersion()
    Dim fileName As String, index As Long, ext As String
    arr = Split(ActiveWorkbook.Name, ".")
    ext = arr(UBound(arr))

    fileName = ActiveWorkbook.FullName

    If InStr(ActiveWorkbook.Name, "_v") = 0 Then
        fileName = ActiveWorkbook.Path & "\" & Left(ActiveWorkbook.Name, InStr(ActiveWorkbook.Name, ".") - 1) & "_v1." & ext
    End If

   Do Until Len(Dir(fileName)) = 0

        index = CInt(Split(Right(fileName, Len(fileName) - InStr(fileName, "_v") - 1), ".")(0))
        index = index + 1
        fileName = Left(fileName, InStr(fileName, "_v") - 1) & "_v" & index & "." & ext

    'Debug.Print fileName
   Loop

    ActiveWorkbook.SaveAs (fileName)
End Sub

How to print Unicode character in Python?

Print a unicode character in Python:

Print a unicode character directly from python interpreter:

el@apollo:~$ python
Python 2.7.3
>>> print u'\u2713'
?

Unicode character u'\u2713' is a checkmark. The interpreter prints the checkmark on the screen.

Print a unicode character from a python script:

Put this in test.py:

#!/usr/bin/python
print("here is your checkmark: " + u'\u2713');

Run it like this:

el@apollo:~$ python test.py
here is your checkmark: ?

If it doesn't show a checkmark for you, then the problem could be elsewhere, like the terminal settings or something you are doing with stream redirection.

Store unicode characters in a file:

Save this to file: foo.py:

#!/usr/bin/python -tt
# -*- coding: utf-8 -*-
import codecs
import sys 
UTF8Writer = codecs.getwriter('utf8')
sys.stdout = UTF8Writer(sys.stdout)
print(u'e with obfuscation: é')

Run it and pipe output to file:

python foo.py > tmp.txt

Open tmp.txt and look inside, you see this:

el@apollo:~$ cat tmp.txt 
e with obfuscation: é

Thus you have saved unicode e with a obfuscation mark on it to a file.

Is there a label/goto in Python?

Python 2 & 3

pip3 install goto-statement

Tested on Python 2.6 through 3.6 and PyPy.

Link: goto-statement


foo.py

from goto import with_goto

@with_goto
def bar():

    label .bar_begin

    ...

    goto .bar_begin

Java - remove last known item from ArrayList

It should be:

ClientThread hey = clients.get(clients.size() - 1);
clients.remove(hey);

Or you can do

clients.remove(clients.size() - 1);

The minus ones are because size() returns the number of elements, but the ArrayList's first element's index is 0 and not 1.

Adding sheets to end of workbook in Excel (normal method not working?)

mainWB.Sheets.Add(After:=Sheets(Sheets.Count)).Name = new_sheet_name 

should probably be

mainWB.Sheets.Add(After:=mainWB.Sheets(mainWB.Sheets.Count)).Name = new_sheet_name 

What's the difference between lists enclosed by square brackets and parentheses in Python?

They are not lists, they are a list and a tuple. You can read about tuples in the Python tutorial. While you can mutate lists, this is not possible with tuples.

In [1]: x = (1, 2)

In [2]: x[0] = 3
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)

/home/user/<ipython console> in <module>()

TypeError: 'tuple' object does not support item assignment

How to set tbody height with overflow scroll

It is simple way to use scroll bar to table body

_x000D_
_x000D_
/* It is simple way to use scroll bar to table body*/

table tbody {
  display: block;
  max-height: 300px;
  overflow-y: scroll;
}

table thead, table tbody tr {
  display: table;
  width: 100%;
  table-layout: fixed;
}
_x000D_
<table>
  <thead>
    <th>Invoice Number</th>
    <th>Purchaser</th>
    <th>Invoice Amount</th>
    <th>Invoice Date</th>
  </thead>
  <tbody>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
    <tr>
      <td>INV-1233</td>
      <td>Dinesh Vaitage</td>
      <td>$300</td>
      <td>01/12/2017</td>
    </tr>
  </tbody>
</table>
_x000D_
_x000D_
_x000D_

Using Position Relative/Absolute within a TD?

also works if you do a "display: block;" on the td, destroying the td identity, but works!

#define in Java

Java doesn't have a general purpose define preprocessor directive.

In the case of constants, it is recommended to declare them as static finals, like in

private static final int PROTEINS = 100;

Such declarations would be inlined by the compilers (if the value is a compile-time constant).

Please note also that public static final constant fields are part of the public interface and their values shouldn't change (as the compiler inlines them). If you do change the value, you would need to recompile all the sources that referenced that constant field.

CSS: Center block, but align contents to the left

For those of us still working with older browsers, here's some extended backwards compatibility:

_x000D_
_x000D_
<div style="text-align: center;">
    <div style="display:-moz-inline-stack; display:inline-block; zoom:1; *display:inline; text-align: left;">
        Line 1: Testing<br>
        Line 2: More testing<br>
        Line 3: Even more testing<br>
    </div>
</div>
_x000D_
_x000D_
_x000D_

Partially inspired by this post: https://stackoverflow.com/a/12567422/14999964.

How to vertically center a container in Bootstrap?

The Flexible box way

Vertical alignment is now very simple by the use of Flexible box layout. Nowadays, this method is supported in a wide range of web browsers except Internet Explorer 8 & 9. Therefore we'd need to use some hacks/polyfills or different approaches for IE8/9.

In the following I'll show you how to do that in only 3 lines of text (regardless of old flexbox syntax).

Note: it's better to use an additional class instead of altering .jumbotron to achieve the vertical alignment. I'd use vertical-center class name for instance.

Example Here (A Mirror on jsbin).

<div class="jumbotron vertical-center"> <!-- 
                      ^--- Added class  -->
  <div class="container">
    ...
  </div>
</div>
.vertical-center {
  min-height: 100%;  /* Fallback for browsers do NOT support vh unit */
  min-height: 100vh; /* These two lines are counted as one :-)       */

  display: flex;
  align-items: center;
}

Important notes (Considered in the demo):

  1. A percentage values of height or min-height properties is relative to the height of the parent element, therefore you should specify the height of the parent explicitly.

  2. Vendor prefixed / old flexbox syntax omitted in the posted snippet due to brevity, but exist in the online example.

  3. In some of old web browsers such as Firefox 9 (in which I've tested), the flex container - .vertical-center in this case - won't take the available space inside the parent, therefore we need to specify the width property like: width: 100%.

  4. Also in some of web browsers as mentioned above, the flex item - .container in this case - may not appear at the center horizontally. It seems the applied left/right margin of auto doesn't have any effect on the flex item.
    Therefore we need to align it by box-pack / justify-content.

For further details and/or vertical alignment of columns, you could refer to the topic below:


The traditional way for legacy web browsers

This is the old answer I wrote at the time I answered this question. This method has been discussed here and it's supposed to work in Internet Explorer 8 and 9 as well. I'll explain it in short:

In inline flow, an inline level element can be aligned vertically to the middle by vertical-align: middle declaration. Spec from W3C:

middle
Align the vertical midpoint of the box with the baseline of the parent box plus half the x-height of the parent.

In cases that the parent - .vertical-center element in this case - has an explicit height, by any chance if we could have a child element having the exact same height of the parent, we would be able to move the baseline of the parent to the midpoint of the full-height child and surprisingly make our desired in-flow child - the .container - aligned to the center vertically.

Getting all together

That being said, we could create a full-height element within the .vertical-center by ::before or ::after pseudo elements and also change the default display type of it and the other child, the .container to inline-block.

Then use vertical-align: middle; to align the inline elements vertically.

Here you go:

<div class="jumbotron vertical-center">
  <div class="container">
    ...
  </div>
</div>
.vertical-center {
  height:100%;
  width:100%;

  text-align: center;  /* align the inline(-block) elements horizontally */
  font: 0/0 a;         /* remove the gap between inline(-block) elements */
}

.vertical-center:before {    /* create a full-height inline block pseudo=element */
  content: " ";
  display: inline-block;
  vertical-align: middle;    /* vertical alignment of the inline element */
  height: 100%;
}

.vertical-center > .container {
  max-width: 100%;

  display: inline-block;
  vertical-align: middle;  /* vertical alignment of the inline element */
                           /* reset the font property */
  font: 16px/1 "Helvetica Neue", Helvetica, Arial, sans-serif;
}

WORKING DEMO.

Also, to prevent unexpected issues in extra small screens, you can reset the height of the pseudo-element to auto or 0 or change its display type to none if needed so:

@media (max-width: 768px) {
  .vertical-center:before {
    height: auto;
    /* Or */
    display: none;
  }
}

UPDATED DEMO

And one more thing:

If there are footer/header sections around the container, it's better to position that elements properly (relative, absolute? up to you.) and add a higher z-index value (for assurance) to keep them always on the top of the others.

How to autosize and right-align GridViewColumn data in WPF?

I know that this is too late but here is my approach:

<GridViewColumn x:Name="GridHeaderLocalSize"  Width="100">      
<GridViewColumn.Header>
    <GridViewColumnHeader HorizontalContentAlignment="Right">
        <Grid Width="Auto" HorizontalAlignment="Right">
            <Grid.ColumnDefinitions>
                <ColumnDefinition Width="100"/>
            </Grid.ColumnDefinitions>
            <TextBlock Grid.Column="0" Text="Local size" TextAlignment="Right" Padding="0,0,5,0"/>
        </Grid>
    </GridViewColumnHeader>
</GridViewColumn.Header>
<GridViewColumn.CellTemplate>
    <DataTemplate>
        <TextBlock Width="{Binding ElementName=GridHeaderLocalSize, Path=Width, FallbackValue=100}"  HorizontalAlignment="Right" TextAlignment="Right" Padding="0,0,5,0" Text="Text" >
        </TextBlock>
    </DataTemplate>
</GridViewColumn.CellTemplate>

The main idea is to bind the width of the cellTemplete element to the width of the ViewGridColumn. Width=100 is default width used until first resize. There isn't any code behind. Everything is in xaml.

Delete item from array and shrink array

You can't resize the array, per se, but you can create a new array and efficiently copy the elements from the old array to the new array using some utility function like this:

public static int[] removeElement(int[] original, int element){
    int[] n = new int[original.length - 1];
    System.arraycopy(original, 0, n, 0, element );
    System.arraycopy(original, element+1, n, element, original.length - element-1);
    return n;
}

A better approach, however, would be to use an ArrayList (or similar List structure) to store your data and then use its methods to remove elements as needed.

Handling JSON Post Request in Go

type test struct {
    Test string `json:"test"`
}

func test(w http.ResponseWriter, req *http.Request) {
    var t test_struct

    body, _ := ioutil.ReadAll(req.Body)
    json.Unmarshal(body, &t)

    fmt.Println(t)
}

Switching to a TabBar tab view programmatically?

My opinion is that selectedIndex or using objectAtIndex is not necessarily the best way to switch the tab. If you reorder your tabs, a hard coded index selection might mess with your former app behavior.

If you have the object reference of the view controller you want to switch to, you can do:

tabBarController.selectedViewController = myViewController

Of course you must make sure, that myViewController really is in the list of tabBarController.viewControllers.

Get Last Part of URL PHP

One liner: $page_path = end(explode('/', trim($_SERVER['REQUEST_URI'], '/')));

Get URI, trim slashes, convert to array, grab last part

What does '&' do in a C++ declaration?

string * and string& differ in a couple of ways. First of all, the pointer points to the address location of the data. The reference points to the data. If you had the following function:

int foo(string *param1);

You would have to check in the function declaration to make sure that param1 pointed to a valid location. Comparatively:

int foo(string &param1);

Here, it is the caller's responsibility to make sure the pointed to data is valid. You can't pass a "NULL" value, for example, int he second function above.

With regards to your second question, about the method return values being a reference, consider the following three functions:

string &foo();
string *foo();
string foo();

In the first case, you would be returning a reference to the data. If your function declaration looked like this:

string &foo()
{
    string localString = "Hello!";
    return localString;
}

You would probably get some compiler errors, since you are returning a reference to a string that was initialized in the stack for that function. On the function return, that data location is no longer valid. Typically, you would want to return a reference to a class member or something like that.

The second function above returns a pointer in actual memory, so it would stay the same. You would have to check for NULL-pointers, though.

Finally, in the third case, the data returned would be copied into the return value for the caller. So if your function was like this:

string foo()
{
    string localString = "Hello!";
    return localString;
}

You'd be okay, since the string "Hello" would be copied into the return value for that function, accessible in the caller's memory space.

Does Hibernate create tables in the database automatically

For me it wasn't working even with hibernate.hbm2ddl.auto set to update. It turned out that the generated creation SQL was invalid, because one of my column names (user) was an SQL keyword. This failed softly, and it wasn't obvious what was going on until I inspected the logs.

How to pass a Javascript Array via JQuery Post so that all its contents are accessible via the PHP $_POST array?

This is fairly straightforward. In your JS, all you would do is this or something similar:

var array = ["thing1", "thing2", "thing3"];

var parameters = {
  "array1[]": array,
  ...
};

$.post(
  'your/page.php',
  parameters
)
.done(function(data, statusText) {
    // This block is optional, fires when the ajax call is complete
});

In your php page, the values in array form will be available via $_POST['array1'].

references

CSS scale down image to fit in containing div, without specifing original size

In a webpage where I wanted a in image to scale with browser size change and remain at the top, next to a fixed div, all I had to do was use a single CSS line: overflow:hidden; and it did the trick. The image scales perfectly.

What is especially nice is that this is pure css and will work even if Javascript is turned off.

CSS:

#ImageContainerDiv {
  overflow: hidden;
}

HTML:

<div id="ImageContainerDiv">
  <a href="URL goes here" target="_blank">
    <img src="MapName.png" alt="Click to load map" />
  </a>
</div>

Unable to send email using Gmail SMTP server through PHPMailer, getting error: SMTP AUTH is required for message submission on port 587. How to fix?

Google treat Gmail accounts differently depending on the available user information, probably to curb spammers.

I couldn't use SMTP until I did the phone verification. Made another account to double check and I was able to confirm it.

Import file size limit in PHPMyAdmin

enter image description here

Open this file

edit these parameters:

  • memory_limit =128M
  • post_max_size = 64M
  • upload_max_filesize = 64M

How to colorize diff on the command line?

Use Vim:

diff /path/to/a /path/to/b | vim -R -

Or better still, VimDiff (or vim -d, which is shorter to type) will show differences between two, three or four files side-by-side.

Examples:

vim -d /path/to/[ab]

vimdiff file1 file2 file3 file4

Trim whitespace from a String

I think that substr() throws an exception if str only contains the whitespace.

I would modify it to the following code:

string trim(string& str)
{
    size_t first = str.find_first_not_of(' ');
    if (first == std::string::npos)
        return "";
    size_t last = str.find_last_not_of(' ');
    return str.substr(first, (last-first+1));
}

Android: How can I validate EditText input?

In main.xml file

You can put the following attrubute to validate only alphabatics character can accept in edittext.

Do this :

  android:entries="abcdefghijklmnopqrstuvwxyz"

Fastest way to convert a dict's keys & values from `unicode` to `str`?

for a non-nested dict (since the title does not mention that case, it might be interesting for other people)

{str(k): str(v) for k, v in my_dict.items()}

Headers and client library minor version mismatch

Changing PHP version from 5.6 to 5.5 Fixed it.

You have to go to control panel > CGI Script and change PHP version there.

What is the best way to redirect a page using React Router?

You also can Redirect within the Route as follows. This is for handle invalid routes.

<Route path='*' render={() => 
     (
       <Redirect to="/error"/>
     )
}/>

MacOSX homebrew mysql root password

Iam using Catalina and use this mysql_secure_installation command and now works for me:

$ mysql_secure_installation
NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
      SERVERS IN PRODUCTION USE!  PLEASE READ EACH STEP CAREFULLY!

In order to log into MariaDB to secure it, we'll need the current
password for the root user. If you've just installed MariaDB, and
haven't set the root password yet, you should just press enter here.

Enter current password for root (enter for none): << enter root here >>

i enter root as current password

OK, successfully used password, moving on...

Setting the root password or using the unix_socket ensures that nobody
can log into the MariaDB root user without the proper authorisation.

and do the rest

Remote branch is not showing up in "git branch -r"

I had the same issue. It seems the easiest solution is to just remove the remote, readd it, and fetch.

Linux: is there a read or recv from socket with timeout?

LINUX

struct timeval tv;
tv.tv_sec = 30;        // 30 Secs Timeout
tv.tv_usec = 0;        // Not init'ing this can cause strange errors
setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, (const char*)&tv,sizeof(struct timeval));

WINDOWS

DWORD timeout = SOCKET_READ_TIMEOUT_SEC * 1000;
setsockopt(socket, SOL_SOCKET, SO_RCVTIMEO, (const char*)&timeout, sizeof(timeout));

NOTE: You have put this setting before bind() function call for proper run

Can I get "&&" or "-and" to work in PowerShell?

We can try this command instead of using && method:

try {hostname; if ($lastexitcode -eq 0) {ipconfig /all | findstr /i bios}} catch {echo err} finally {}

Java constant examples (Create a java file having only constants)

This question is old. But I would like to mention an other approach. Using Enums for declaring constant values. Based on the answer of Nandkumar Tekale, the Enum can be used as below:

Enum:

public enum Planck {
    REDUCED();
    public static final double PLANCK_CONSTANT = 6.62606896e-34;
    public static final double PI = 3.14159;
    public final double REDUCED_PLANCK_CONSTANT;

    Planck() {
        this.REDUCED_PLANCK_CONSTANT = PLANCK_CONSTANT / (2 * PI);
    }

    public double getValue() {
        return REDUCED_PLANCK_CONSTANT;
    }
}

Client class:

public class PlanckClient {

    public static void main(String[] args) {
        System.out.println(getReducedPlanckConstant());
        // or using Enum itself as below:
        System.out.println(Planck.REDUCED.getValue());
    }

    public static double getReducedPlanckConstant() {
        return Planck.PLANCK_CONSTANT / (2 * Planck.PI);
    }

}

Reference : The usage of Enums for declaring constant fields is suggested by Joshua Bloch in his Effective Java book.

Ways to implement data versioning in MongoDB

If you are using mongoose, I have found the following plugin to be a useful implementation of the JSON Patch format

mongoose-patch-history

How to debug (only) JavaScript in Visual Studio?

First open Visual studio ..select your project in solution explorer..Right click and choose option "browse with" then set IE as default browser.

enter image description here Now open IE ..go to
Tools >> Internet option >> Advance>> uncheck the checkbox having "Disable Script Debugging (Internet Explorer). and then click Apply and OK and you are done ..

Now you can set breakpoints in your JS file and then hit the debug button in VS..

enter image description here

EDIT:- For asp.net web application right click on the page which is your startup page(say default.aspx) and perform the same steps. :)

Round float to x decimals?

I feel compelled to provide a counterpoint to Ashwini Chaudhary's answer. Despite appearances, the two-argument form of the round function does not round a Python float to a given number of decimal places, and it's often not the solution you want, even when you think it is. Let me explain...

The ability to round a (Python) float to some number of decimal places is something that's frequently requested, but turns out to be rarely what's actually needed. The beguilingly simple answer round(x, number_of_places) is something of an attractive nuisance: it looks as though it does what you want, but thanks to the fact that Python floats are stored internally in binary, it's doing something rather subtler. Consider the following example:

>>> round(52.15, 1)
52.1

With a naive understanding of what round does, this looks wrong: surely it should be rounding up to 52.2 rather than down to 52.1? To understand why such behaviours can't be relied upon, you need to appreciate that while this looks like a simple decimal-to-decimal operation, it's far from simple.

So here's what's really happening in the example above. (deep breath) We're displaying a decimal representation of the nearest binary floating-point number to the nearest n-digits-after-the-point decimal number to a binary floating-point approximation of a numeric literal written in decimal. So to get from the original numeric literal to the displayed output, the underlying machinery has made four separate conversions between binary and decimal formats, two in each direction. Breaking it down (and with the usual disclaimers about assuming IEEE 754 binary64 format, round-ties-to-even rounding, and IEEE 754 rules):

  1. First the numeric literal 52.15 gets parsed and converted to a Python float. The actual number stored is 7339460017730355 * 2**-47, or 52.14999999999999857891452847979962825775146484375.

  2. Internally as the first step of the round operation, Python computes the closest 1-digit-after-the-point decimal string to the stored number. Since that stored number is a touch under the original value of 52.15, we end up rounding down and getting a string 52.1. This explains why we're getting 52.1 as the final output instead of 52.2.

  3. Then in the second step of the round operation, Python turns that string back into a float, getting the closest binary floating-point number to 52.1, which is now 7332423143312589 * 2**-47, or 52.10000000000000142108547152020037174224853515625.

  4. Finally, as part of Python's read-eval-print loop (REPL), the floating-point value is displayed (in decimal). That involves converting the binary value back to a decimal string, getting 52.1 as the final output.

In Python 2.7 and later, we have the pleasant situation that the two conversions in step 3 and 4 cancel each other out. That's due to Python's choice of repr implementation, which produces the shortest decimal value guaranteed to round correctly to the actual float. One consequence of that choice is that if you start with any (not too large, not too small) decimal literal with 15 or fewer significant digits then the corresponding float will be displayed showing those exact same digits:

>>> x = 15.34509809234
>>> x
15.34509809234

Unfortunately, this furthers the illusion that Python is storing values in decimal. Not so in Python 2.6, though! Here's the original example executed in Python 2.6:

>>> round(52.15, 1)
52.200000000000003

Not only do we round in the opposite direction, getting 52.2 instead of 52.1, but the displayed value doesn't even print as 52.2! This behaviour has caused numerous reports to the Python bug tracker along the lines of "round is broken!". But it's not round that's broken, it's user expectations. (Okay, okay, round is a little bit broken in Python 2.6, in that it doesn't use correct rounding.)

Short version: if you're using two-argument round, and you're expecting predictable behaviour from a binary approximation to a decimal round of a binary approximation to a decimal halfway case, you're asking for trouble.

So enough with the "two-argument round is bad" argument. What should you be using instead? There are a few possibilities, depending on what you're trying to do.

  • If you're rounding for display purposes, then you don't want a float result at all; you want a string. In that case the answer is to use string formatting:

    >>> format(66.66666666666, '.4f')
    '66.6667'
    >>> format(1.29578293, '.6f')
    '1.295783'
    

    Even then, one has to be aware of the internal binary representation in order not to be surprised by the behaviour of apparent decimal halfway cases.

    >>> format(52.15, '.1f')
    '52.1'
    
  • If you're operating in a context where it matters which direction decimal halfway cases are rounded (for example, in some financial contexts), you might want to represent your numbers using the Decimal type. Doing a decimal round on the Decimal type makes a lot more sense than on a binary type (equally, rounding to a fixed number of binary places makes perfect sense on a binary type). Moreover, the decimal module gives you better control of the rounding mode. In Python 3, round does the job directly. In Python 2, you need the quantize method.

    >>> Decimal('66.66666666666').quantize(Decimal('1e-4'))
    Decimal('66.6667')
    >>> Decimal('1.29578293').quantize(Decimal('1e-6'))
    Decimal('1.295783')
    
  • In rare cases, the two-argument version of round really is what you want: perhaps you're binning floats into bins of size 0.01, and you don't particularly care which way border cases go. However, these cases are rare, and it's difficult to justify the existence of the two-argument version of the round builtin based on those cases alone.

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

It seems to me that your Hibernate libraries are not found (NoClassDefFoundError: org/hibernate/boot/archive/scan/spi/ScanEnvironment as you can see above).

Try checking to see if Hibernate core is put in as dependency:

<dependency>
  <groupId>org.hibernate</groupId>
  <artifactId>hibernate-core</artifactId>
  <version>5.0.11.Final</version>
  <scope>compile</scope>
</dependency>

UITableView load more when scrolling to bottom like Facebook application

Below link will provide sample code. #Swift3

User need to pull up last table view cell, at least hight of 2 cell to fetch more data from server.

You will found Process cell also to show loading process as in last cell.

Its in Swift3

https://github.com/yogendrabagoriya/YBTableViewPullData

How to select between brackets (or quotes or ...) in Vim?

Write a Vim function in .vimrc using the searchpair built-in function:

searchpair({start}, {middle}, {end} [, {flags} [, {skip}
            [, {stopline} [, {timeout}]]]])
    Search for the match of a nested start-end pair.  This can be
    used to find the "endif" that matches an "if", while other
    if/endif pairs in between are ignored.
    [...]

(http://vimdoc.sourceforge.net/htmldoc/eval.html)

Does VBA have Dictionary Structure?

Yes.

Set a reference to MS Scripting runtime ('Microsoft Scripting Runtime'). As per @regjo's comment, go to Tools->References and tick the box for 'Microsoft Scripting Runtime'.

References Window

Create a dictionary instance using the code below:

Set dict = CreateObject("Scripting.Dictionary")

or

Dim dict As New Scripting.Dictionary 

Example of use:

If Not dict.Exists(key) Then 
    dict.Add key, value
End If 

Don't forget to set the dictionary to Nothing when you have finished using it.

Set dict = Nothing 

Resize Cross Domain Iframe Height

If you have access to manipulate the code of the site you are loading, the following should provide a comprehensive method to updating the height of the iframe container anytime the height of the framed content changes.

Add the following code to the pages you are loading (perhaps in a header). This code sends a message containing the height of the HTML container any time the DOM is updated (if you're lazy loading) or the window is resized (when the user modifies the browser).

window.addEventListener("load", function(){
    if(window.self === window.top) return; // if w.self === w.top, we are not in an iframe 
    send_height_to_parent_function = function(){
        var height = document.getElementsByTagName("html")[0].clientHeight;
        //console.log("Sending height as " + height + "px");
        parent.postMessage({"height" : height }, "*");
    }
    // send message to parent about height updates
    send_height_to_parent_function(); //whenever the page is loaded
    window.addEventListener("resize", send_height_to_parent_function); // whenever the page is resized
    var observer = new MutationObserver(send_height_to_parent_function);           // whenever DOM changes PT1
    var config = { attributes: true, childList: true, characterData: true, subtree:true}; // PT2
    observer.observe(window.document, config);                                            // PT3 
});

Add the following code to the page that the iframe is stored on. This will update the height of the iframe, given that the message came from the page that that iframe loads.

<script>
window.addEventListener("message", function(e){
    var this_frame = document.getElementById("healthy_behavior_iframe");
    if (this_frame.contentWindow === e.source) {
        this_frame.height = e.data.height + "px";
        this_frame.style.height = e.data.height + "px";
    }
})
</script>