Programs & Examples On #Code complexity

How to return an array from an AJAX call?

Php has a super sexy function for this, just pass the array to it:

$json = json_encode($var);

dataType : "json",

simples :)

No operator matches the given name and argument type(s). You might need to add explicit type casts. -- Netbeans, Postgresql 8.4 and Glassfish

If anyone is having this exception and is building the query using Scala multi-line strings:

Looks like there is a problem with some JPA drivers in this situation. I'm not sure what is the character Scala uses for LINE END, but when you have a parameter right at the end of the line, the LINE END character seems to be attached to the parameter and so when the driver parses the query, this error comes up. A simple work around is to leave an empty space right after the param at the end:

SELECT * FROM some_table a
WHERE a.col = ?param
AND a.col2 = ?param2

So, just make sure to leave an empty space after param (and param2, if you have a line break there).

What does auto do in margin:0 auto?

It is a broken/very hard to use replacement for the "center" tag. It comes in handy when you need broken tables and non-working centering for blocks and text.

Android: converting String to int

It's already a string? Remove the getText() call.

int myNum = 0;

try {
    myNum = Integer.parseInt(myString);
} catch(NumberFormatException nfe) {
  // Handle parse error.

programmatically add column & rows to WPF Datagrid

To Bind the DataTable into the DataGridTextColumn in CodeBehind xaml



  foreach (DataColumn col in dt.Columns)
      new DataGridTextColumn
        Header = col.ColumnName,
        Binding = new Binding(string.Format("[{0}]", col.ColumnName))

  TrkDataGrid.ItemsSource= dt.DefaultView;

Input and Output binary streams using JERSEY?

I found the following helpful to me and I wanted to share in case it helps you or someone else. I wanted something like MediaType.PDF_TYPE, which doesn't exist, but this code does the same thing:



In my case I was posting a PDF document to another site:

FormDataMultiPart p = new FormDataMultiPart();
p.bodyPart(new FormDataBodyPart(FormDataContentDisposition
        new File("path/to/document.pdf"),

Then p gets passed as the second parameter to post().

This link was helpful to me in putting this code snippet together:

What is the difference between single and double quotes in SQL?

Single quotes are used to indicate the beginning and end of a string in SQL. Double quotes generally aren't used in SQL, but that can vary from database to database.

Stick to using single quotes.

That's the primary use anyway. You can use single quotes for a column alias — where you want the column name you reference in your application code to be something other than what the column is actually called in the database. For example: would be more readable as product_id, so you use either of the following:

  • SELECT AS product_id
  • SELECT 'product_id'

Either works in Oracle, SQL Server, MySQL… but I know some have said that the TOAD IDE seems to give some grief when using the single quotes approach.

You do have to use single quotes when the column alias includes a space character, e.g., product id, but it's not recommended practice for a column alias to be more than one word.

jQuery remove all list items from an unordered list

An example using .remove():

<p>Remove LI's from list</p>

setTimeout(function(){$('ul li').remove();},1000);

Also, .empty() should have worked.

Credit card expiration dates - Inclusive or exclusive?

lots of big companies dont even use your expiration date anymore because it causes auto-renewal of payments to be lost when cards are issued with new expiration dates and the same account number. This has been a huge problem in the service industry, so these companies have cornered the card issuers into processing payments w/o expiration dates to avoid this pitfall. Not many people know about this yet, so not all companies use this practice.

HTML5 Email input pattern attribute

This is the approach I'm using and you can modify it based on your needs:



  1. We want to make sure that the e-mail address always starts with a word:


A word is any character, digit or underscore. You can use [a-zA-Z0-9_] pattern, but it will give you the same result and it's longer.

  1. Next, we want to make sure that there is at least one such character:


  2. Next, we want to allow any word, digit or special characters in the name. This way, we can be sure that the e-mail won't start with the dot, but can contain the dot on other than the first position:


  3. And of course, there doesn't have to be any of such character because e-mail address can have only one letter followed by @:


  4. Next, we need the @ character which is mandatory, but there can be only one in the whole e-mail:


  5. Right behind the @ character, we want the domain name. Here, you can define how many characters you want as minimum and from which range of characters. I'd go for all word characters including the hyphen [\w-] and I want at least two of them {2,}. If you want to allow domains like, you would have to allow one character from this range {1,}:


  6. Next, we need to deal with two cases. Either there's just the domain name followed by the domain extension, or there's subdomain name followed by the domain name followed by the extension, for example, versus To make this work, we need to use the (a|b) token where a stands for the first case, b stands for the second case and | stands for logical OR. In the first case, we will deal with just the domain extension, but since it will be always there no matter the case, we can safely add it to both cases:


This pattern says that we need exactly one dot character followed by letters, no digits, and we want at least two of them, in both cases.

  1. For the second case, we will add the domain name in front of the domain extension, thus making the original domain name a subdomain:


The domain name can consist of word characters including the hyphen and again, we want at least two characters here.

  1. Finally, we need to mark the end of the whole pattern:


  2. Go here and test if your e-mail matches the pattern:

Disallow Twitter Bootstrap modal window from closing

You can also include these attributes in the modal definition itself:

<div class="modal hide fade" data-keyboard="false" data-backdrop="static">

When to use Interface and Model in TypeScript / Angular

Interfaces are only at compile time. This allows only you to check that the expected data received follows a particular structure. For this you can cast your content to this interface:

    .map(res => <Product[]>res.json());

See these questions:

You can do something similar with class but the main differences with class are that they are present at runtime (constructor function) and you can define methods in them with processing. But, in this case, you need to instantiate objects to be able to use them:

    .map(res => {
      var data = res.json();
      return => {
        return new Product(d.productNumber,
          d.productName, d.productDescription);

How enable auto-format code for Intellij IDEA?

Well that's not possible, but in intellij 13, how about adding a mouse gesture, something like single left mouse click to reformat the code? Or if you don't use the mouse much then add a very simple keyboard hotkey that you use all the time (possibly the "enter"? not sure if intellij would be happy with that to be honest)

grant remote access of MySQL database from any IP address

  • START MYSQL using admin user
    • mysql -u admin-user -p (ENTER PASSWORD ON PROMPT)
  • Create a new user:
    • CREATE USER 'newuser'@'%' IDENTIFIED BY 'password'; (% -> anyhost)
  • Grant Privileges:
    • GRANT SELECT,DELETE,INSERT,UPDATE ON db_name.* TO 'newuser'@'%';

If you are running EC2 instance don't forget to add the inbound rules in security group with MYSQL/Aurura.

Understanding the Gemfile.lock file

What does the exclamation mark after the gem name in the 'DEPENDECIES' group mean?

The exclamation mark appears when the gem was installed using a source other than "".

JS file gets a net::ERR_ABORTED 404 (Not Found)

As mentionned in comments: you need a way to send your static files to the client. This can be achieved with a reverse proxy like Nginx, or simply using express.static().

Put all your "static" (css, js, images) files in a folder dedicated to it, different from where you put your "views" (html files in your case). I'll call it static for the example. Once it's done, add this line in your server code:

app.use("/static", express.static('./static/'));

This will effectively serve every file in your "static" folder via the /static route.

Querying your index.js file in the client thus becomes:

<script src="static/index.js"></script>

Standard way to embed version into python package?

I use a JSON file in the package dir. This fits Zooko's requirements.

Inside pkg_dir/pkg_info.json:

{"version": "0.1.0"}


from distutils.core import setup
import json

with open('pkg_dir/pkg_info.json') as fp:
    _info = json.load(fp)


Inside pkg_dir/

import json
from os.path import dirname

with open(dirname(__file__) + '/pkg_info.json') as fp:
    _info = json.load(fp)

__version__ = _info['version']

I also put other information in pkg_info.json, like author. I like to use JSON because I can automate management of metadata.

Does Java support default parameter values?

You may use Java Method Invocation Builder to automatically generate the builder with default values.

Just add @GenerateMethodInvocationBuilder to the class, or interface, and the @Default to parameters in methods where you want default values. A builder will be generated at compile time, using the default values that you specified with your annotations.

public class CarService {
 public CarService() {

 public String getCarsByFilter(//
   @Default("Color.BLUE") Color color, //
   @Default("new ProductionYear(2001)") ProductionYear productionYear,//
   @Default("Tomas") String owner//
 ) {
  return "Filtering... " + color + productionYear + owner;

And then you can invoke the methods.

CarService instance = new CarService();
String carsByFilter = CarServiceGetCarsByFilterBuilder.getCarsByFilter()//

Or set any of the default values to something else.

CarService instance = new CarService();
String carsByFilter = CarServiceGetCarsByFilterBuilder.getCarsByFilter()//

Receiver not registered exception error?

I used a try - catch block to solve the issue temporarily.

// Unregister Observer - Stop monitoring the underlying data source.
        if (mDataSetChangeObserver != null) {
            // Sometimes the Fragment onDestroy() unregisters the observer before calling below code
            // See <a></a>
            try  {
                mDataSetChangeObserver = null;
            catch (IllegalArgumentException e) {
                // Check wether we are in debug mode
                if (BuildConfig.IS_DEBUG_MODE) {

clientHeight/clientWidth returning different values on different browsers

This has to do with the browser's box model. Use something like jQuery or another JavaScript abstraction library to normalize the DOM model.

Text editor to open big (giant, huge, large) text files

Tips and tricks


Why are you using editors to just look at a (large) file?

Under *nix or Cygwin, just use less. (There is a famous saying – "less is more, more or less" – because "less" replaced the earlier Unix command "more", with the addition that you could scroll back up.) Searching and navigating under less is very similar to Vim, but there is no swap file and little RAM used.

There is a Win32 port of GNU less. See the "less" section of the answer above.


Perl is good for quick scripts, and its .. (range flip-flop) operator makes for a nice selection mechanism to limit the crud you have to wade through.

For example:

$ perl -n -e 'print if ( 1000000 .. 2000000)' humongo.txt | less

This will extract everything from line 1 million to line 2 million, and allow you to sift the output manually in less.

Another example:

$ perl -n -e 'print if ( /regex one/ .. /regex two/)' humongo.txt | less

This starts printing when the "regular expression one" finds something, and stops when the "regular expression two" find the end of an interesting block. It may find multiple blocks. Sift the output...


This is another useful tool you can use. To quote the Wikipedia article:

logparser is a flexible command line utility that was initially written by Gabriele Giuseppini, a Microsoft employee, to automate tests for IIS logging. It was intended for use with the Windows operating system, and was included with the IIS 6.0 Resource Kit Tools. The default behavior of logparser works like a "data processing pipeline", by taking an SQL expression on the command line, and outputting the lines containing matches for the SQL expression.

Microsoft describes Logparser as a powerful, versatile tool that provides universal query access to text-based data such as log files, XML files and CSV files, as well as key data sources on the Windows operating system such as the Event Log, the Registry, the file system, and Active Directory. The results of the input query can be custom-formatted in text based output, or they can be persisted to more specialty targets like SQL, SYSLOG, or a chart.

Example usage:

C:\>logparser.exe -i:textline -o:tsv "select Index, Text from 'c:\path\to\file.log' where line > 1000 and line < 2000"
C:\>logparser.exe -i:textline -o:tsv "select Index, Text from 'c:\path\to\file.log' where line like '%pattern%'"

The relativity of sizes

100 MB isn't too big. 3 GB is getting kind of big. I used to work at a print & mail facility that created about 2% of U.S. first class mail. One of the systems for which I was the tech lead accounted for about 15+% of the pieces of mail. We had some big files to debug here and there.

And more...

Feel free to add more tools and information here. This answer is community wiki for a reason! We all need more advice on dealing with large amounts of data...

What is the best way to connect and use a sqlite database from C#

Here I am trying to help you do the job step by step: (this may be the answer to other questions)

  1. Go to this address , down the page you can see something like "List of Release Packages". Based on your system and .net framework version choose the right one for you. for example if your want to use .NET Framework 4.6 on a 64-bit Windows, choose this version and download it.
  2. Then install the file somewhere on your hard drive, just like any other software.
  3. Open Visual studio and your project. Then in solution explorer, right-click on "References" and choose "add Reference...".
  4. Click the browse button and choose where you install the previous file and go to .../bin/System.Data.SQLite.dll and click add and then OK buttons.

that is pretty much it. now you can use SQLite in your project. to use it in your project on the code level you may use this below example code:

  1. make a connection string:

    string connectionString = @"URI=file:{the location of your sqlite database}";

  2. establish a sqlite connection:

    SQLiteConnection theConnection = new SQLiteConnection(connectionString );

  3. open the connection:


  4. create a sqlite command:

    SQLiteCommand cmd = new SQLiteCommand(theConnection);

  5. Make a command text, or better said your SQLite statement:

    cmd.CommandText = "INSERT INTO table_name(col1, col2) VALUES(val1, val2)";

  6. Execute the command


that is it.

Unable to convert MySQL date/time value to System.DateTime

If I google for "Unable to convert MySQL date/time value to System.DateTime" I see numerous references to a problem accessing MySQL from Visual Studio. Is that your context?

One solution suggested is:

This is not a bug but expected behavior. Please check manual under connect options and set "Allow Zero Datetime" to true, as on attached pictures, and the error will go away.


UITextView that expands to text using auto layout

BTW, I built an expanding UITextView using a subclass and overriding intrinsic content size. I discovered a bug in UITextView that you might want to investigate in your own implementation. Here is the problem:

The expanding text view would grow down to accommodate the growing text if you type single letters at a time. But if you paste a bunch of text into it, it would not grow down but the text would scroll up and the text at the top was out of view.

The solution: Override setBounds: in your subclass. For some unknown reason, the pasting caused the bounds.origin.y value to be non-zee (33 in every case that I saw). So I overrode setBounds: to always set the bounds.origin.y to zero. Fixed the problem.

Difference between <input type='button' /> and <input type='submit' />

Button won't submit form on its own.It is a simple button which is used to perform some operation by using javascript whereas Submit is a kind of button which by default submit the form whenever user clicks on submit button.

What are .iml files in Android Studio?

They are project files, that hold the module information and meta data.

Just add *.iml to .gitignore.

In Android Studio: Press CTRL + F9 to rebuild your project. The missing *.iml files will be generated.

mkdir's "-p" option

Note that -p is an argument to the mkdir command specifically, not the whole of Unix. Every command can have whatever arguments it needs.

In this case it means "parents", meaning mkdir will create a directory and any parents that don't already exist.

php function mail() isn't working

I think you are not configured properly,

if you are using XAMPP then you can easily send mail from localhost.

for example you can configure C:\xampp\php\php.ini and c:\xampp\sendmail\sendmail.ini for gmail to send mail.

in C:\xampp\php\php.ini find extension=php_openssl.dll and remove the semicolon from the beginning of that line to make SSL working for gmail for localhost.

in php.ini file find [mail function] and change
sendmail_from = [email protected]
sendmail_path = "C:\xampp\sendmail\sendmail.exe -t"

(use the above send mail path only and it will work)

Now Open C:\xampp\sendmail\sendmail.ini. Replace all the existing code in sendmail.ini with following code

[email protected]
[email protected]

Now you have done!! create php file with mail function and send mail from localhost.


First, make sure you PHP installation has SSL support (look for an "openssl" section in the output from phpinfo()).

You can set the following settings in your PHP.ini:


Convert `List<string>` to comma-separated string

In .NET 4 you don't need the ToArray() call - string.Join is overloaded to accept IEnumerable<T> or just IEnumerable<string>.

There are potentially more efficient ways of doing it before .NET 4, but do you really need them? Is this actually a bottleneck in your code?

You could iterate over the list, work out the final size, allocate a StringBuilder of exactly the right size, then do the join yourself. That would avoid the extra array being built for little reason - but it wouldn't save much time and it would be a lot more code.

Styling HTML5 input type number

Also you can replace size attribute by a style attribute:
<input type="number" name="numericInput" style="width: 50px;" min="0" max="18" value="0" />

How to retrieve a single file from a specific revision in Git?

If you wish to replace/overwrite the content of a file in your current branch with the content of the file from a previous commit or a different branch, you can do so with these commands:

git checkout 08618129e66127921fbfcbc205a06153c92622fe path/to/file.txt


git checkout mybranchname path/to/file.txt

You will then have to commit those changes in order for them to be effective in the current branch.

How to Identify Microsoft Edge browser via CSS?

For Internet Explorer 

@media all and (-ms-high-contrast: none) {
            background: rgba(0, 0, 0, 0.16)

For Edge
@supports (-ms-ime-align:auto) {
            background: rgba(0, 0, 0, 0.16);

Get all mysql selected rows into an array

I would suggest the use of MySQLi or MySQL PDO for performance and security purposes, but to answer the question:

while($row = mysql_fetch_assoc($result)){
     $json[] = $row;

echo json_encode($json);

If you switched to MySQLi you could do:

$query = "SELECT * FROM table";
$result = mysqli_query($db, $query);

$json = mysqli_fetch_all ($result, MYSQLI_ASSOC);
echo json_encode($json );

Sort Java Collection

With Java 8 you have several options, combining method references and the built-in comparing comparator:

import static java.util.Comparator.comparing;

Collection<CustomObject> list = new ArrayList<CustomObject>();

Collections.sort(list, comparing(CustomObject::getId));

Remove scrollbars from textarea

Hide scroll bar for Mozilla.

  overflow: -moz-hidden-unscrollable;

Is #pragma once a safe include guard?

I use it and I'm happy with it, as I have to type much less to make a new header. It worked fine for me in three platforms: Windows, Mac and Linux.

I don't have any performance information but I believe that the difference between #pragma and the include guard will be nothing comparing to the slowness of parsing the C++ grammar. That's the real problem. Try to compile the same number of files and lines with a C# compiler for example, to see the difference.

In the end, using the guard or the pragma, won't matter at all.

How to create a windows service from java app

With Apache Commons Daemon you can now have a custom executable name and icon! You can also get a custom Windows tray monitor with your own name and icon!

I now have my service running with my own name and icon (prunsrv.exe), and the system tray monitor (prunmgr.exe) also has my own custom name and icon!

  1. Download the Apache Commons Daemon binaries (you will need prunsrv.exe and prunmgr.exe).

  2. Rename them to be MyServiceName.exe and MyServiceNamew.exe respectively.

  3. Download WinRun4J and use the RCEDIT.exe program that comes with it to modify the Apache executable to embed your own custom icon like this:

    > RCEDIT.exe /I MyServiceName.exe customIcon.ico
    > RCEDIT.exe /I MyServiceNamew.exe customTrayIcon.ico
  4. Now install your Windows service like this (see documentation for more details and options):

    > MyServiceName.exe //IS//MyServiceName \
      --Install="C:\path-to\MyServiceName.exe" \
      --Jvm=auto --Startup=auto --StartMode=jvm \
      --Classpath="C:\path-to\MyJarWithClassWithMainMethod.jar" \
  5. Now you have a Windows service of your Jar that will run with your own icon and name! You can also launch the monitor file and it will run in the system tray with your own icon and name.

    > MyServiceNamew.exe //MS//MyServiceName

Postgresql SQL: How check boolean field with null and True,False Value?

I'm not expert enough in the inner workings of Postgres to know why your query with the double condition in the WHERE clause be not working. But one way to get around this would be to use a UNION of the two queries which you know do work:

SELECT * FROM table_name WHERE boolean_column IS NULL
SELECT * FROM table_name WHERE boolean_column = FALSE

You could also try using COALESCE:

SELECT * FROM table_name WHERE COALESCE(boolean_column, FALSE) = FALSE

This second query will replace all NULL values with FALSE and then compare against FALSE in the WHERE condition.

What is the right way to write my script 'src' url for a local development environment?

Write the src tag for calling the js file as

<script type='text/javascript' src='../Users/myUserName/Desktop/myPage.js'></script>

This should work.

git pull keeping local changes

Incase their is local uncommitted changes and avoid merge conflict while pulling.

git stash save
git pull
git stash pop

refer -

How to create an android app using HTML 5

You can write complete apps for almost any smartphone platform (Android, iOS,...) using Phonegap. (

It is an open source framework that exposes native capabilities to a web view, so that you can do anything a native app can do.

This is very suitable for cross platform development if you're not building something that has to be pixel perfect in every way, or is very hardware intensive.

If you are looking for UI Frameworks that can be used to build such apps, there is a wide range of different libraries. (Like Sencha, jQuery mobile, ...)

And to be a little biased, there is something I built as well:

Can I obtain method parameter name using Java reflection?

While it is not possible (as others have illustrated), you could use an annotation to carry over the parameter name, and obtain that though reflection.

Not the cleanest solution, but it gets the job done. Some webservices actually do this to keep parameter names (ie: deploying WSs with glassfish).

Converting HTML to Excel?

So long as Excel can open the file, the functionality to change the format of the opened file is built in.

To convert an .html file, open it using Excel (File - Open) and then save it as a .xlsx file from Excel (File - Save as).

To do it using VBA, the code would look like this:

Sub Open_HTML_Save_XLSX()

    Workbooks.Open Filename:="C:\Temp\Example.html"
    ActiveWorkbook.SaveAs Filename:= _
        "C:\Temp\Example.xlsx", FileFormat:= _

End Sub

Set output of a command as a variable (with pipes)

The lack of a Linux-like backtick/backquote facility is a major annoyance of the pre-PowerShell world. Using backquotes via for-loops is not at all cosy. So we need kinda of setvar myvar cmd-line command.

In my %path% I have a dir with a number of bins and batches to cope with those Win shortcomings.

One batch I wrote is:

:: setvar varname cmd
:: Set VARNAME to the output of CMD
:: Triple escape pipes, eg:
:: setvar x  dir c:\ ^^^| sort 
:: -----------------------------

@echo off

:: Get command from argument 
for /F "tokens=1,*" %%a in ("%*") do set cmd=%%b

:: Get output and set var
for /F "usebackq delims=" %%a in (`%cmd%`) do (
     set %1=%%a

:: Show results 
SETLOCAL EnableDelayedExpansion
echo %1=!%1! 

So in your case, you would type:

> setvar text echo Hello

The script informs you of the results, which means you can:

> echo text var is now %text%
text var is now Hello 

You can use whatever command:

> setvar text FIND "Jones" names.txt

What if the command you want to pipe to some variable contains itself a pipe?
Triple escape it, ^^^|:

> setvar text dir c:\ ^^^| find "Win"

SOAP client in .NET - references or examples?

Here you can find a nice tutorial for calling a NuSOAP-based web-service from a .NET client application. But IMO, you should also consider the WSO2 Web Services Framework for PHP (WSO2 WSF/PHP) for servicing. See WSO2 Web Services Framework for PHP 2.0 Significantly Enhances Industry’s Only PHP Library for Creating Both SOAP and REST Services. There is also a webminar about it.

Now, in .NET world I also encourage the use of WCF, taking into account the interoperability issues. An interoperability example can be found here, but this example uses a PHP-client + WCF-service instead of the opposite. Feel free to implement the PHP-service & WFC-client.

There are some WCF's related open source projects on that I found very productive. These projects are very useful to design & implement Win Forms and Windows Presentation Foundation applications: Smart Client, Web Client and Mobile Client. They can be used in combination with WCF to wisely call any kind of Web services.

Generally speaking, the patterns & practices team summarize good practices & designs in various open source projects that dealing with the .NET platform, specially for the web. So I think it's a good starting point for any design decision related to .NET clients.

How to use session in JSP pages to get information?

The reason why you are getting the compilation error is, you are trying to access the session in declaration block (<%! %>) where it is not available. All the implicit objects of jsp are available in service method only. Code of declarative blocks goes outside the service method.

I'd advice you to use EL. It is a simplified approach.

${sessionScope.username} would give you the desired output.

Java Try and Catch IOException Problem

Initializer block is just like any bits of code; it's not "attached" to any field/method preceding it. To assign values to fields, you have to explicitly use the field as the lhs of an assignment statement.

private int lineCount; {
        lineCount = LineCounter.countLines(sFileName);
    catch(IOException ex){
        System.out.println (ex.toString());
        System.out.println("Could not find file " + sFileName);

Also, your countLines can be made simpler:

  public static int countLines(String filename) throws IOException {
    LineNumberReader reader  = new LineNumberReader(new FileReader(filename));
    while (reader.readLine() != null) {}
    return reader.getLineNumber();

Based on my test, it looks like you can getLineNumber() after close().

Upload file to SFTP using PowerShell

I am able to sftp using PowerShell as below:

PS C:\Users\user\Desktop> sftp [email protected]                                                     
[email protected]'s password:
Connected to [email protected].
sftp> ls
sftp> cd testFolder
sftp> ls
sftp> put taj_mahal_1.jpeg
Uploading taj_mahal_1.jpeg to /home/user/testFolder/taj_mahal_1.jpeg
taj_mahal_1.jpeg                                                                      100%   11KB  35.6KB/s   00:00
sftp> ls
taj_mahal.jpeg      taj_mahal_1.jpeg

I do not have installed Posh-SSH or anything like that. I am using Windows 10 Pro PowerShell. No additional modules installed.

CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to create a collapsed table with rounded corners?

I figured it out. You just have to use some special selectors.

The problem with rounding the corners of the table was that the td elements didn't also become rounded. You can solve that by doing something like this:

table tr:last-child td:first-child {
    border-bottom-left-radius: 10px;

table tr:last-child td:last-child {
    border-bottom-right-radius: 10px;

Now everything rounds properly, except that there's still the issue of border-collapse: collapse breaking everything.

A workaround is to add border-spacing: 0 and leave the default border-collapse: separate on the table.

How to save DataFrame directly to Hive?

I don't see df.write.saveAsTable(...) deprecated in Spark 2.0 documentation. It has worked for us on Amazon EMR. We were perfectly able to read data from S3 into a dataframe, process it, create a table from the result and read it with MicroStrategy. Vinays answer has also worked though.

C++ delete vector, objects, free memory

You can call clear, and that will destroy all the objects, but that will not free the memory. Looping through the individual elements will not help either (what action would you even propose to take on the objects?) What you can do is this:


That will create an empty vector with no memory allocated and swap it with tempVector, effectively deallocating the memory.

C++11 also has the function shrink_to_fit, which you could call after the call to clear(), and it would theoretically shrink the capacity to fit the size (which is now 0). This is however, a non-binding request, and your implementation is free to ignore it.

Refresh an page on button click

On button click you can try the following.

protected void button1_Click(object sender, EventArgs e)

And on PageLoad you can check whether the loading is coming from that button then increase the count.

       protected void Page_Load(object sender, EventArgs e)
            StackTrace stackTrace = new StackTrace();
            string eventName = stackTrace.GetFrame(1).GetMethod().Name; // this will the event name.
            if (eventName == "button1_Click")
                // code to increase the count;


Eclipse returns error message "Java was started but returned exit code = 1"

My path of -javaagent argument was having Spacial characters like '&'. I placed the Lambok jar in different place and gave the path to that place. It worked for me.

previously it was

-javaagent:C:\Software & Tool\lambok.jar

i changed it to


MomentJS getting JavaScript Date in UTC

Calling toDate will create a copy (the documentation is down-right wrong about it not being a copy), of the underlying JS Date object. JS Date object is stored in UTC and will always print to eastern time. Without getting into whether .utc() modifies the underlying object that moment wraps use the code below.

You don't need moment for this.

new Date().getTime()

This works, because JS Date at its core is in UTC from the Unix Epoch. It's extraordinarily confusing and I believe a big flaw in the interface to mix local and UTC times like this with no descriptions in the methods.

reactjs - how to set inline style of backgroundcolor?

You don't need the quotes.

<a style={{backgroundColor: bgColors.Yellow}}>yellow</a>

How to place a div on the right side with absolute position

Simple, use absolute positioning, and instead of specifying a top and a left, specify a top and a right!

For example:

#logo_image {
    z-index: 3;

How to get root access on Android emulator?

I believe that the easiest way is to create an alias for the command sh, e.g.

adb shell
mount -o rw,remount -t yaffs2 /dev/block/mtdblock3 /system
cd /system/bin
cat sh > su && chmod 4775 su

Tested on Android Emulator 3.0 and higher.

css overflow - only 1 line of text

If you want to indicate that there's still more content available in that div, you may probably want to show the "ellipsis":

text-overflow: ellipsis;

This should be in addition to white-space: nowrap; suggested by Septnuits.

Also, make sure you checkout this thread to handle this in Firefox.

How to get file's last modified date on Windows command line?

You could try the 'Last Written' time options associated with the DIR command

/T:C -- Creation Time and Date
/T:A -- Last Access Time and Date
/T:W -- Last Written Time and Date (default)

DIR /T:W myfile.txt

The output from the above command will produce a variety of additional details you probably wont need, so you could incorporate two FINDSTR commands to remove blank lines, plus any references to 'Volume', 'Directory' and 'bytes':

DIR /T:W myfile.txt | FINDSTR /v "^$" | FINDSTR /v /c:"Volume" /c:"Directory" /c:"bytes"

Attempts to incorporate the blank line target (/c:"^$" or "^$") within a single FINDSTR command fail to remove the blank lines (or produce other errors) when the results are output to a text file.

This is a cleaner command:

DIR /T:W myfile.txt | FINDSTR /c:"/"

Connecting to SQL Server with Visual Studio Express Editions

I just happened to have started my home business application in windows forms for the convenience. I'm currently using Visual C# Express 2010 / SQL Server 2008 R2 Express to develop it. I got the same problem as OP where I need to connect to an instance of SQL server. I'm skipping details here but that database will be a merged database synched between 2-3 computers that will also use the application I'm developing right now.

I found a quick workaround, at least, I think I did because I'm now able to use my stored procedures in tableadapters without any issues so far.

I copy pasted an SQL connection that I used in a different project at work (VS2010 Premium) in the app.config and changed everything I needed there. When I went back to my Settings.settings, I just had to confirm that I wanted what was inside the app.config file. The only downsides I can see is that you can't "test" the connection since when you go inside the configuration of the connection string you can't go anywhere since "SQL Server" is not an option. The other downside is that you need to input everything manually since you can't use any wizards to make it work.

I don't know if I should have done it that way but at least I can connect to my SQL server now :).


It only works with SQL Server 2008 R2 Express instances. If you try with SQL Server 2008 R2 Workgroup and up, you'll get a nasty warning from Visual C# 2010 Express telling you that "you can't use that connection with the current version of Visual Studio". I got that when I was trying to modify some of my tableadapters. I switched back to an SQL Express instance to develop and it's working fine again.

String was not recognized as a valid DateTime " format dd/MM/yyyy"

Change Manually :

string s = date.Substring(3, 2) +"/" + date.Substring(0, 2) + "/" + date.Substring(6, 4);

From 11/22/2015 it will be converted in 22/11/2015

Iterating through struct fieldnames in MATLAB

Your fns is a cellstr array. You need to index in to it with {} instead of () to get the single string out as char.


Indexing in to it with () returns a 1-long cellstr array, which isn't the same format as the char array that the ".(name)" dynamic field reference wants. The formatting, especially in the display output, can be confusing. To see the difference, try this.

name_as_char = 'a'
name_as_cellstr = {'a'}

How to pass an array to a function in VBA?

Your function worked for me after changing its declaration to this ...

Function processArr(Arr As Variant) As String

You could also consider a ParamArray like this ...

Function processArr(ParamArray Arr() As Variant) As String
    'Dim N As Variant
    Dim N As Long
    Dim finalStr As String
    For N = LBound(Arr) To UBound(Arr)
        finalStr = finalStr & Arr(N)
    Next N
    processArr = finalStr
End Function

And then call the function like this ...

processArr("foo", "bar")

diff to output only the file names

From the diff man page:

-q   Report only whether the files differ, not the details of the differences.
-r   When comparing directories, recursively compare any subdirectories found.

Example command:

diff -qr dir1 dir2

Example output (depends on locale):

$ ls dir1 dir2
same-file  different  only-1

same-file  different  only-2
$ diff -qr dir1 dir2
Files dir1/different and dir2/different differ
Only in dir1: only-1
Only in dir2: only-2

Import error No module named skimage

Hey this is pretty simple to solve this error.Just follow this steps:

First uninstall any existing installation:

pip uninstall scikit-image

or, on conda-based systems:

conda uninstall scikit-image

Now, clone scikit-image on your local computer, and install:

git clone
cd scikit-image
pip install -e .

To update the installation:

git pull  # Grab latest source
pip install -e .  # Reinstall

For other os and manual process please check this Link.

How to detect when a UIScrollView has finished scrolling

I've tried Ashley Smart's answer and it worked like a charm. Here's another idea, with using only scrollViewDidScroll

-(void)scrollViewDidScroll:(UIScrollView *)sender 
    if(self.scrollView_Result.contentOffset.x == self.scrollView_Result.frame.size.width)       {
    // You have reached page 1

I just had two pages so it worked for me. However, if you have more than one page, it could be problematic (you could check whether the current offset is a multiple of the width but then you wouldn't know if the user stopped at 2nd page or is on his way to 3rd or more)

Download old version of package with NuGet

By using the Nuget Package Manager UI as mentioned above it helps to uninstall the nuget package first. I always have problems when going back on a nuget package version if I don't uninstall first. Some references are not cleaned properly. So I suggest the following workflow when installing an old nuget package through the Nuget Package Manager:

  1. Selected your nuget server / source
  2. Find and select the nuget package your want to install an older version
  3. Uninstall current version
  4. Click on the install drop-down > Select older version > Click Install

enter image description here

Good Luck :)

Golang read request body

I could use the GetBody from Request package.

Look this comment in source code from request.go in net/http:

GetBody defines an optional func to return a new copy of Body. It is used for client requests when a redirect requires reading the body more than once. Use of GetBody still requires setting Body. For server requests it is unused."

GetBody func() (io.ReadCloser, error)

This way you can get the body request without make it empty.


getBody := request.GetBody
copyBody, err := getBody()
if err != nil {
    // Do something return err

Is it possible to assign a base class object to a derived class reference with an explicit typecast?

You can use a copy constructor that immediately invokes the instance constructor, or if your instance constructor does more than assignments have the copy constructor assign the incoming values to the instance.

class Person
    // Copy constructor 
    public Person(Person previousPerson)
        Name = previousPerson.Name;
        Age = previousPerson.Age;

    // Copy constructor calls the instance constructor.
    public Person(Person previousPerson)
        : this(previousPerson.Name, previousPerson.Age)

    // Instance constructor.
    public Person(string name, int age)
        Name = name;
        Age = age;

    public int Age { get; set; }

    public string Name { get; set; }

Referenced the Microsoft C# Documentation under Constructor for this example having had this issue in the past.

What's the difference between "end" and "exit sub" in VBA?

This is a bit outside the scope of your question, but to avoid any potential confusion for readers who are new to VBA: End and End Sub are not the same. They don't perform the same task.

End puts a stop to ALL code execution and you should almost always use Exit Sub (or Exit Function, respectively).

End halts ALL exectution. While this sounds tempting to do it also clears all global and static variables. (source)

See also the MSDN dox for the End Statement

When executed, the End statement resets allmodule-level variables and all static local variables in allmodules. To preserve the value of these variables, use the Stop statement instead. You can then resume execution while preserving the value of those variables.

Note The End statement stops code execution abruptly, without invoking the Unload, QueryUnload, or Terminate event, or any other Visual Basic code. Code you have placed in the Unload, QueryUnload, and Terminate events offorms andclass modules is not executed. Objects created from class modules are destroyed, files opened using the Open statement are closed, and memory used by your program is freed. Object references held by other programs are invalidated.

Nor is End Sub and Exit Sub the same. End Sub can't be called in the same way Exit Sub can be, because the compiler doesn't allow it.

enter image description here

This again means you have to Exit Sub, which is a perfectly legal operation:

Exit Sub
Immediately exits the Sub procedure in which it appears. Execution continues with the statement following the statement that called the Sub procedure. Exit Sub can be used only inside a Sub procedure.

Additionally, and once you get the feel for how procedures work, obviously, End Sub does not clear any global variables. But it does clear local (Dim'd) variables:

End Sub
Terminates the definition of this procedure.

How to add an action to a UIAlertView button using Swift iOS

Swift 4 Update

        // Create the alert controller
        let alertController = UIAlertController(title: "Title", message: "Message", preferredStyle: .alert)

        // Create the actions
        let okAction = UIAlertAction(title: "OK", style: UIAlertActionStyle.default) {
            UIAlertAction in
            NSLog("OK Pressed")
        let cancelAction = UIAlertAction(title: "Cancel", style: UIAlertActionStyle.cancel) {
            UIAlertAction in
            NSLog("Cancel Pressed")

        // Add the actions

        // Present the controller
        self.present(alertController, animated: true, completion: nil)

Replace image src location using CSS

Here is another dirty hack :)

.application-title > img {
display: none;

.application-title::before {
content: url(path/example.jpg);

How to convert from int to string in objective c: example code

Simply convert int to NSString use :

  int x=10;

  NSString *strX=[NSString stringWithFormat:@"%d",x];

How to print Unicode character in C++?

To represent the character you can use Universal Character Names (UCNs). The character '?' has the Unicode value U+0444 and so in C++ you could write it '\u0444' or '\U00000444'. Also if the source code encoding supports this character then you can just write it literally in your source code.

// both of these assume that the character can be represented with
// a single char in the execution encoding
char b = '\u0444';
char a = '?'; // this line additionally assumes that the source character encoding supports this character

Printing such characters out depends on what you're printing to. If you're printing to a Unix terminal emulator, the terminal emulator is using an encoding that supports this character, and that encoding matches the compiler's execution encoding, then you can do the following:

#include <iostream>

int main() {
    std::cout << "Hello, ? or \u0444!\n";

This program does not require that '?' can be represented in a single char. On OS X and most any modern Linux install this will work just fine, because the source, execution, and console encodings will all be UTF-8 (which supports all Unicode characters).

Things are harder with Windows and there are different possibilities with different tradeoffs.

Probably the best, if you don't need portable code (you'll be using wchar_t, which should really be avoided on every other platform), is to set the mode of the output file handle to take only UTF-16 data.

#include <iostream>
#include <io.h>
#include <fcntl.h>

int main() {
    _setmode(_fileno(stdout), _O_U16TEXT);
    std::wcout << L"Hello, \u0444!\n";

Portable code is more difficult.

Validate phone number using javascript

can anyone explain why

because your regular expression does match the input. It's just that the input also includes the extra characters. You included '^' to signify the beginning of line, but (as Andy said) you should include '$' to signify the end of line.

If you start your regex with '^' and end it with '$', then it will only match lines that only match your regex.

By starting your regex with '^' and not ending it with '$', you match lines that start with a sequence matching your regex, but lines can have anything else trailing the matching sequence.

Showing an image from console in Python

Since you are probably running Windows (from looking at your tags), this would be the easiest way to open and show an image file from the console without installing extra stuff like PIL.

import os
os.system('start pic.png')

How to import a new font into a project - Angular 5

You need to put the font files in assets folder (may be a fonts sub-folder within assets) and refer to it in the styles:

@font-face {
  font-family: lato;
  src: url(assets/font/Lato.otf) format("opentype");

Once done, you can apply this font any where like:

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'lato', 'arial', sans-serif;

You can put the @font-face definition in your global styles.css or styles.scss and you would be able to refer to the font anywhere - even in your component specific CSS/SCSS. styles.css or styles.scss is already defined in angular-cli.json. Or, if you want you can create a separate CSS/SCSS file and declare it in angular-cli.json along with the styles.css or styles.scss like:

"styles": [

How to get parameter value for date/time column from empty MaskedTextBox

You're storing the .Text properties of the textboxes directly into the database, this doesn't work. The .Text properties are Strings (i.e. simple text) and not typed as DateTime instances. Do the conversion first, then it will work.

Do this for each date parameter:

Dim bookIssueDate As DateTime = DateTime.ParseExact( txtBookDateIssue.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture ) cmd.Parameters.Add( New OleDbParameter("@Date_Issue", bookIssueDate ) ) 

Note that this code will crash/fail if a user enters an invalid date, e.g. "64/48/9999", I suggest using DateTime.TryParse or DateTime.TryParseExact, but implementing that is an exercise for the reader.

Travel/Hotel API's?

HotelsCombined has an easy-to-access and useful service to download the data feed files with hotels. Not exactly API, but something you can get, parse and use. Here is how you do it:

  1. Go to
  2. Register there (no company or bank data is needed)
  3. Open “Data feeds” page
  4. Choose “Standard data feed” -> “Single file” -> “CSV format” (you may get XML as well)

If you are interested in details, you may find the sample Python code to filter CSV file to get hotels for a specific city here:


Unfortunately, has introduced the new regulations: they've restricted the access to data feeds by default. To get the access, a partner must submit some information on why one needs the data. The HC team will review it and then (maybe) will grant access.

How to compare strings in an "if" statement?

if(strcmp(aString, bString) == 0){
    //strings are the same


SQL error "ORA-01722: invalid number"

This happened to me too, but the problem was actually different: file encoding.

The file was correct, but the file encoding was wrong. It was generated by the export utility of SQL Server and I saved it as Unicode.

The file itself looked good in the text editor, but when I opened the *.bad file that the SQL*loader generated with the rejected lines, I saw it had bad characters between every original character. Then I though about the encoding.

I opened the original file with Notepad++ and converted it to ANSI, and everything loaded properly.

How To Change DataType of a DataColumn in a DataTable?

Puedes agregar una columna con tipo de dato distinto , luego copiar los datos y eliminar la columna anterior

TB.Columns.Add("columna1", GetType(Integer))    
TB.Select("id=id").ToList().ForEach(Sub(row) row("columna1") = row("columna2"))    

How to add a border to a widget in Flutter?

Here is an expanded answer. A DecoratedBox is what you need to add a border, but I am using a Container for the convenience of adding margin and padding.

Here is the general setup.

enter image description here

Widget myWidget() {
  return Container(
    margin: const EdgeInsets.all(30.0),
    padding: const EdgeInsets.all(10.0),
    decoration: myBoxDecoration(), //             <--- BoxDecoration here
    child: Text(
      style: TextStyle(fontSize: 30.0),

where the BoxDecoration is

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(),

Border width

enter image description here

These have a border width of 1, 3, and 10 respectively.

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      width: 1, //                   <--- border width here

Border color

enter image description here

These have a border color of



BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      color:, //                   <--- border color
      width: 5.0,

Border side

enter image description here

These have a border side of

  • left (3.0), top (3.0)
  • bottom (13.0)
  • left (blue[100], 15.0), top (blue[300], 10.0), right (blue[500], 5.0), bottom (blue[800], 3.0)


BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border(
      left: BorderSide( //                   <--- left side
        width: 3.0,
      top: BorderSide( //                    <--- top side
        width: 3.0,

Border radius

enter image description here

These have border radii of 5, 10, and 30 respectively.

BoxDecoration myBoxDecoration() {
  return BoxDecoration(
    border: Border.all(
      width: 3.0
    borderRadius: BorderRadius.all(
        Radius.circular(5.0) //                 <--- border radius here

Going on

DecoratedBox/BoxDecoration are very flexible. Read Flutter — BoxDecoration Cheat Sheet for many more ideas.

Recommended add-ons/plugins for Microsoft Visual Studio

Sonic File Finder for when you have loads of files in your solutions and searching for them in the solution explorer becomes a pain in the wrist.

You might also find DPack interesting. Several tools and enhancements rolled into one neat package.

getting the index of a row in a pandas apply function

To access the index in this case you access the name attribute:

In [182]:

df = pd.DataFrame([[1,2,3],[4,5,6]], columns=['a','b','c'])
def rowFunc(row):
    return row['a'] + row['b'] * row['c']

def rowIndex(row):
df['d'] = df.apply(rowFunc, axis=1)
df['rowIndex'] = df.apply(rowIndex, axis=1)
   a  b  c   d  rowIndex
0  1  2  3   7         0
1  4  5  6  34         1

Note that if this is really what you are trying to do that the following works and is much faster:

In [198]:

df['d'] = df['a'] + df['b'] * df['c']
   a  b  c   d
0  1  2  3   7
1  4  5  6  34

In [199]:

%timeit df['a'] + df['b'] * df['c']
%timeit df.apply(rowIndex, axis=1)
10000 loops, best of 3: 163 µs per loop
1000 loops, best of 3: 286 µs per loop


Looking at this question 3+ years later, you could just do:

df['d'],df['rowIndex'] = df['a'] + df['b'] * df['c'], df.index

   a  b  c   d  rowIndex
0  1  2  3   7         0
1  4  5  6  34         1

but assuming it isn't as trivial as this, whatever your rowFunc is really doing, you should look to use the vectorised functions, and then use them against the df index:

df['newCol'] = df['a'] + df['b'] + df['c'] + df.index

   a  b  c   d  rowIndex  newCol
0  1  2  3   7         0       6
1  4  5  6  34         1      16

'dict' object has no attribute 'has_key'

has_key has been deprecated in Python 3.0. Alternatively you can use 'in'


print('A' in graph)
>> True

print('E' in graph)
>> False

What is the command for cut copy paste a file from one directory to other directory

mv in unix-ish systems, move in dos/windows.


C:\> move c:\users\you\somefile.txt   c:\temp\newlocation.txt


$ mv /home/you/somefile.txt /tmp/newlocation.txt

how to get bounding box for div element in jquery

As this is specifically tagged for jQuery -




(These are functionally identical, in some older browsers .get() was slightly faster)

Note that if you try to get the values via jQuery calls then it will not take into account any css transform values, which can give unexpected results...

Note 2: In jQuery 3.0 it has changed to using the proper getBoundingClientRect() calls for its own dimension calls (see the jQuery Core 3.0 Upgrade Guide) - which means that the other jQuery answers will finally always be correct - but only when using the new jQuery version - hence why it's called a breaking change...

raw vs. html_safe vs. h to unescape html

I think it bears repeating: html_safe does not HTML-escape your string. In fact, it will prevent your string from being escaped.

<%= "<script>alert('Hello!')</script>" %>

will put:


into your HTML source (yay, so safe!), while:

<%= "<script>alert('Hello!')</script>".html_safe %>

will pop up the alert dialog (are you sure that's what you want?). So you probably don't want to call html_safe on any user-entered strings.

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.

How to convert data.frame column from Factor to numeric

This is FAQ 7.10. Others have shown how to apply this to a single column in a data frame, or to multiple columns in a data frame. But this is really treating the symptom, not curing the cause.

A better approach is to use the colClasses argument to read.table and related functions to tell R that the column should be numeric so that it never creates a factor and creates numeric. This will put in NA for any values that do not convert to numeric.

Another better option is to figure out why R does not recognize the column as numeric (usually a non numeric character somewhere in that column) and fix the original data so that it is read in properly without needing to create NAs.

Best is a combination of the last 2, make sure the data is correct before reading it in and specify colClasses so R does not need to guess (this can speed up reading as well).

.htaccess: Invalid command 'RewriteEngine', perhaps misspelled or defined by a module not included in the server configuration

I can see that your using AppServ, mod_rewrite is disabled by default on that WAMP package (just googled it)


Find: C:/AppServ/Apache/conf/httpd.conf file.

and un-comment this line #LoadModule rewrite_module modules/

Restart apache... Simplez

keycloak Invalid parameter: redirect_uri

It seems that this problem can occur if you put whitespace in your Realm name. I had name set to Debugging Realm and I got this error. When I changed to DebuggingRealm it worked.

You can still have whitespace in the display name. Odd that keycloak doesn't check for this on admin input.

Can I make 'git diff' only the line numbers AND changed file names?

git diff master --compact-summary

Output is:

 src/app/components/common/sidebar/toolbar/toolbar.component.html   |  2 +-
 src/app/components/common/sidebar/toolbar/toolbar.component.scss   |  2 --

This is exactly what you need. Same format as when you making commit or pulling new commits from remote.

PS: That's wired that nobody answered this way.

Should I use PATCH or PUT in my REST API?

I would recommend using PATCH, because your resource 'group' has many properties but in this case, you are updating only the activation field(partial modification)

according to the RFC5789 (

The existing HTTP PUT method only allows a complete replacement of a document. This proposal adds a new HTTP method, PATCH, to modify an existing HTTP resource.

Also, in more details,

The difference between the PUT and PATCH requests is reflected in the way the server processes the enclosed entity to modify the resource
identified by the Request-URI. In a PUT request, the enclosed entity is considered to be a modified version of the resource stored on the
origin server, and the client is requesting that the stored version
be replaced. With PATCH, however, the enclosed entity contains a set of instructions describing how a resource currently residing on the
origin server should be modified to produce a new version. The PATCH method affects the resource identified by the Request-URI, and it
also MAY have side effects on other resources; i.e., new resources
may be created, or existing ones modified, by the application of a

PATCH is neither safe nor idempotent as defined by [RFC2616], Section 9.1.

Clients need to choose when to use PATCH rather than PUT. For
example, if the patch document size is larger than the size of the
new resource data that would be used in a PUT, then it might make
sense to use PUT instead of PATCH. A comparison to POST is even more difficult, because POST is used in widely varying ways and can
encompass PUT and PATCH-like operations if the server chooses. If
the operation does not modify the resource identified by the Request- URI in a predictable way, POST should be considered instead of PATCH
or PUT.

The response code for PATCH is

The 204 response code is used because the response does not carry a message body (which a response with the 200 code would have). Note that other success codes could be used as well.

also refer t

Caveat: An API implementing PATCH must patch atomically. It MUST not be possible that resources are half-patched when requested by a GET.

How to set the min and max height or width of a Frame?

A workaround - at least for the minimum size: You can use grid to manage the frames contained in root and make them follow the grid size by setting sticky='nsew'. Then you can use root.grid_rowconfigure and root.grid_columnconfigure to set values for minsize like so:

from tkinter import Frame, Tk

class MyApp():
    def __init__(self):
        self.root = Tk()

        self.my_frame_red = Frame(self.root, bg='red')
        self.my_frame_red.grid(row=0, column=0, sticky='nsew')

        self.my_frame_blue = Frame(self.root, bg='blue')
        self.my_frame_blue.grid(row=0, column=1, sticky='nsew')

        self.root.grid_rowconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(0, minsize=200, weight=1)
        self.root.grid_columnconfigure(1, weight=1)


if __name__ == '__main__':
    app = MyApp()

But as Brian wrote (in 2010 :D) you can still resize the window to be smaller than the frame if you don't limit its minsize.

How do I set a JLabel's background color?



Otherwise the background is not painted, since the default of opaque is false for JLabel.

From the JavaDocs:

If true the component paints every pixel within its bounds. Otherwise, the component may not paint some or all of its pixels, allowing the underlying pixels to show through.

For more information, read the Java Tutorial How to Use Labels.

SSL InsecurePlatform error when using Requests package

I don't use this in production, just some test runners. And to reiterate the urllib3 documentation

If you know what you are doing and would like to disable this and other warnings

import requests.packages.urllib3

Edit / Update:

The following should also work:

import logging
import requests

# turn down requests log verbosity

Navigation Drawer (Google+ vs. YouTube)

There is a great implementation of NavigationDrawer that follows the Google Material Design Guidelines (and compatible down to API 10) - The MaterialDrawer library (link to GitHub). As of time of writing, May 2017, it's actively supported.

It's available in Maven Central repo. Gradle dependency setup:

compile 'com.mikepenz:materialdrawer:5.9.1'

Maven dependency setup:


enter image description here enter image description here

heroku - how to see all the logs

Follow on Heroku logging

To view your logs we have:

  1. logs command retrives 100 log lines by default.

heroku logs

  1. show maximum 1500 lines, --num (or -n) option.

heroku logs -n 200

  1. Show logs in real time

heroku logs --tail

  1. If you have many apps on heroku

heroku logs --app your_app_name

How to position a CSS triangle using ::after?

Just add position:relative to the parent element .sidebar-resources-categories

explanation: the ::after elements position is based off of it's parent, in your example you probably had a parent element of the .sidebar-res... which had a set height, therefore it rendered just below it. Adding position relative to the .sidebar-res... makes the after elements move to 100% of it's parent which now becomes the .sidebar-res... because it's position is set to relative. I'm not sure how to explain it but it's expected behaviour.

read more on the subject:

What command means "do nothing" in a conditional in Bash?

You can probably just use the true command:

if [ "$a" -ge 10 ]; then
elif [ "$a" -le 5 ]; then
    echo "1"
    echo "2"

An alternative, in your example case (but not necessarily everywhere) is to re-order your if/else:

if [ "$a" -le 5 ]; then
    echo "1"
elif [ "$a" -lt 10 ]; then
    echo "2"

HttpContext.Current.User.Identity.Name is Empty

Try enabling basic authentication and disabling the other authentications in IIS, then try launching the application. The application will ask for windows credentials. Enter the same and the app should be able to get the name under HttpContext.Current.User.Identity.Name.

Calculating bits required to store decimal number

There are a lot of answers here, but I'll add my approach since I found this post while working on the same problem.

Starting with what we know here are the number from 0 to 16.

Number           encoded in bits         minimum number of bits to encode
0                000000                  1
1                000001                  1
2                000010                  2
3                000011                  2
4                000100                  3
5                000101                  3
6                000110                  3
7                000111                  3
8                001000                  4
9                001001                  4
10               001010                  4
11               001011                  4
12               001100                  4
13               001101                  4
14               001110                  4
15               001111                  4
16               010000                  5

looking at the breaks, it shows this table

number <=       number of bits
1               0
3               2
7               3
15              4

So, now how do we compute the pattern?

Remember that log base 2 (n) = log base 10 (n) / log base 10 (2)

number    logb10 (n)   logb2 (n)   ceil[logb2(n)] 
1         0            0           0           (special case)
3         0.477        1.58        2
7         0.845        2.807       3  
8         0.903        3           3           (special case)
15        1.176        3.91        4
16        1.204        4           4           (special case)
31        1.491        4.95        5
63        1.799        5.98        6

Now the desired result matching the first table. Notice how also some values are special cases. 0 and any number which is a powers of 2. These values dont change when you apply ceiling so you know you need to add 1 to get the minimum bit field length.

To account for the special cases add one to the input. The resulting code implemented in python is:

from math import log
from math import ceil
def min_num_bits_to_encode_number(a_number):
    a_number=a_number+1  # adjust by 1 for special cases

    # log of zero is undefined
    if 0==a_number:
        return 0
    num_bits = int(ceil(log(a_number,2)))  # logbase2 is available
    return (num_bits)

How to launch html using Chrome at "--allow-file-access-from-files" mode?

Depending on the file which will be put into filesystem, as long as that file is not a malware, then that would be safe.

But don't worry to write/read file(s) to File System directory, cause you can tighten that directory security (include it's inheritance) by give a proper access right and security restriction. eg: read/write/modify.

By default, File System, Local Storage, and Storage directory are located on "\Users[Current User]\AppData\Local\Google\Chrome\User Data\Default" directory.

However you can customize it by using "--user-data-dir" flag.

And this is a sample:

"C:\Program Files (x86)\Google\Application\chrome.exe" --user-data-dir="C:\Chrome_Data\OO7" --allow-file-access-from-files

Hope this helps anyone.

How to deselect all selected rows in a DataGridView control?

To deselect all rows and cells in a DataGridView, you can use the ClearSelection method:


If you don't want even the first row/cell to appear selected, you can set the CurrentCell property to Nothing/null, which will temporarily hide the focus rectangle until the control receives focus again:

myDataGridView.CurrentCell = Nothing

To determine when the user has clicked on a blank part of the DataGridView, you're going to have to handle its MouseUp event. In that event, you can HitTest the click location and watch for this to indicate HitTestInfo.Nowhere. For example:

Private Sub myDataGridView_MouseUp(ByVal sender as Object, ByVal e as System.Windows.Forms.MouseEventArgs)
    ''# See if the left mouse button was clicked
    If e.Button = MouseButtons.Left Then
        ''# Check the HitTest information for this click location
        If myDataGridView.HitTest(e.X, e.Y) = DataGridView.HitTestInfo.Nowhere Then
            myDataGridView.CurrentCell = Nothing
        End If
    End If
End Sub

Of course, you could also subclass the existing DataGridView control to combine all of this functionality into a single custom control. You'll need to override its OnMouseUp method similar to the way shown above. I also like to provide a public DeselectAll method for convenience that both calls the ClearSelection method and sets the CurrentCell property to Nothing.

(Code samples are all arbitrarily in VB.NET because the question doesn't specify a language—apologies if this is not your native dialect.)

LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression

In MVC, assume you are searching record(s) based on your requirement or information. It is working properly.

public ActionResult SearchRecord(FormCollection formcollection)
    EmployeeContext employeeContext = new EmployeeContext();

    string searchby=formcollection["SearchBy"];
    string value=formcollection["Value"];

    if (formcollection["SearchBy"] == "Gender")
        List<MvcApplication1.Models.Employee> emplist = employeeContext.Employees.Where(x => x.Gender == value).ToList();
        return View("Index", emplist);
        List<MvcApplication1.Models.Employee> emplist = employeeContext.Employees.Where(x => x.Name == value).ToList();
        return View("Index", emplist);

Force browser to refresh css, javascript, etc

The accepted answer above is correct. If, however, you only want to reload the cache periodically, and you are using Firefox, the Web Developer tools (under the Tools menu item as of November 2015) provides a Network option. This includes a Reload button. Select the Reload for a once off cache reset.

How to get the path of current worksheet in VBA?

The quickest way

path = ThisWorkbook.Path & "\"

How do I create and store md5 passwords in mysql

Please don't use MD5 for password hashing. Such passwords can be cracked in milliseconds. You're sure to be pwned by cybercriminals.

PHP offers a high-quality and future proof password hashing subsystem based on a reliable random salt and multiple rounds of Rijndael / AES encryption.

When a user first provides a password you can hash it like this:

 $pass = 'whatever the user typed in';
 $hashed_password = password_hash( "secret pass phrase", PASSWORD_DEFAULT );

Then, store $hashed_password in a varchar(255) column in MySQL. Later, when the user wants to log in, you can retrieve the hashed password from MySQL and compare it to the password the user offered to log in.

 $pass = 'whatever the user typed in';
 $hashed_password = 'what you retrieved from MySQL for this user';
 if ( password_verify ( $pass , $hashed_password )) {
    /* future proof the password */
    if ( password_needs_rehash($hashed_password , PASSWORD_DEFAULT)) {
       /* recreate the hash */
       $rehashed_password = password_hash($pass, PASSWORD_DEFAULT );
       /* store the rehashed password in MySQL */
     /* password verified, let the user in */
 else {
     /* password not verified, tell the intruder to get lost */

How does this future-proofing work? Future releases of PHP will adapt to match faster and easier to crack encryption. If it's necessary to rehash passwords to make them harder to crack, the future implementation of the password_needs_rehash() function will detect that.

Don't reinvent the flat tire. Use professionally designed and vetted open source code for security.

How do search engines deal with AngularJS applications?

Things have changed quite a bit since this question was asked. There are now options to let Google index your AngularJS site. The easiest option I found was to use free service that will generate the crwalable pages for you and serve that to the search engines. It is supported on almost all server side web platforms. I have recently started using them and the support is excellent too.

I do not have any affiliation with them, this is coming from a happy user.

How to declare a variable in a template in Angular

Here is a directive I wrote that expands on the use of the exportAs decorator parameter, and allows you to use a dictionary as a local variable.

import { Directive, Input } from "@angular/core";
export class LocalVariables {
    @Input("localVariables") set localVariables( struct: any ) {
        if ( typeof struct === "object" ) {
            for( var variableName in struct ) {
                this[variableName] = struct[variableName];
    constructor( ) {

You can use it as follows in a template:

<div #local="localVariables" [localVariables]="{a: 1, b: 2, c: 3+2}">
   <span>a = {{local.a}}</span>
   <span>b = {{local.b}}</span>
   <span>c = {{local.c}}</span>

Of course #local can be any valid local variable name.

How to see which flags -march=native will activate?

It should be (-### is similar to -v):

echo | gcc -### -E - -march=native 

To show the "real" native flags for gcc.

You can make them appear more "clearly" with a command:

gcc -### -E - -march=native 2>&1 | sed -r '/cc1/!d;s/(")|(^.* - )//g'

and you can get rid of flags with -mno-* with:

gcc -### -E - -march=native 2>&1 | sed -r '/cc1/!d;s/(")|(^.* - )|( -mno-[^\ ]+)//g'

Curl error: Operation timed out

Your curl gets timed out. Probably the url you are trying that requires more that 30 seconds.

If you are running the script through browser, then set the set_time_limit to zero for infinite seconds.


Increase the curl's operation time limit using this option CURLOPT_TIMEOUT

curl_setopt($ch, CURLOPT_TIMEOUT,500); // 500 seconds

It can also happen for infinite redirection from the server. To halt this try to run the script with follow location disabled.

curl_setopt($ch, CURLOPT_FOLLOWLOCATION, false);

How to convert an entire MySQL database characterset and collation to UTF-8?

If you cannot get your tables to convert or your table is always set to some non-utf8 character set, but you want utf8, your best bet might be to wipe it out and start over again and explicitly specify:

create database database_name character set utf8;

Git Remote: Error: fatal: protocol error: bad line length character: Unab

I had the same kind of problem after installing GIT on Windows. At first it worked; then, a day later (after a PC reboot), it didn't anymore, and I got this:

$ git pull
fatal: protocol error: bad line length character: git@

The problem was that after the reboot, the automatically started Putty "pageant.exe" didn't have the private key active anymore. When you add a key in pageant, it's not a persistent setting by default. I just had to add the key again, and it worked fine. So, for that case, it's necessary to make pagenant load the key automatically, as discussed here:

How to send a correct authorization header for basic authentication

Per and , here is how to do Basic auth with a header instead of putting the username and password in the URL. Note that this still doesn't hide the username or password from anyone with access to the network or this JS code (e.g. a user executing it in a browser):

  type: 'POST',
  data: {},
  crossDomain: true,
  beforeSend: function(xhr) {
    xhr.setRequestHeader('Authorization', 'Basic ' + btoa(unescape(encodeURIComponent(YOUR_USERNAME + ':' + YOUR_PASSWORD))))

Best way to implement keyboard shortcuts in a Windows Forms application?

You probably forgot to set the form's KeyPreview property to True. Overriding the ProcessCmdKey() method is the generic solution:

protected override bool ProcessCmdKey(ref Message msg, Keys keyData) {
  if (keyData == (Keys.Control | Keys.F)) {
    MessageBox.Show("What the Ctrl+F?");
    return true;
  return base.ProcessCmdKey(ref msg, keyData);

Swift error : signal SIGABRT how to solve it

For me it wasn't an outlet. I solved the problem by going to the error And reading what it said. (Also Noob..)

This was the error:

enter image description here

And The solution was here: enter image description here

Just scroll up in the output and the error will be revealed.

How to Read and Write from the Serial Port

I spent a lot of time to use SerialPort class and has concluded to use SerialPort.BaseStream class instead. You can see source code: SerialPort-source and SerialPort.BaseStream-source for deep understanding. I created and use code that shown below.

  • The core function public int Recv(byte[] buffer, int maxLen) has name and works like "well known" socket's recv().

  • It means that

    • in one hand it has timeout for no any data and throws TimeoutException.
    • In other hand, when any data has received,
      • it receives data either until maxLen bytes
      • or short timeout (theoretical 6 ms) in UART data flow


public class Uart : SerialPort

        private int _receiveTimeout;

        public int ReceiveTimeout { get => _receiveTimeout; set => _receiveTimeout = value; }

        static private string ComPortName = "";

        /// <summary>
        /// It builds PortName using ComPortNum parameter and opens SerialPort.
        /// </summary>
        /// <param name="ComPortNum"></param>
        public Uart(int ComPortNum) : base()
            base.BaudRate = 115200; // default value           
            _receiveTimeout = 2000;
            ComPortName = "COM" + ComPortNum;

                base.PortName = ComPortName;
            catch (UnauthorizedAccessException ex)
                Console.WriteLine("Error: Port {0} is in use", ComPortName);
            catch (Exception ex)
                Console.WriteLine("Uart exception: " + ex);
        } //Uart()

        /// <summary>
        /// Private property returning positive only Environment.TickCount
        /// </summary>
        private int _tickCount { get => Environment.TickCount & Int32.MaxValue; }

        /// <summary>
        /// It uses SerialPort.BaseStream rather SerialPort functionality .
        /// It Receives up to maxLen number bytes of data, 
        /// Or throws TimeoutException if no any data arrived during ReceiveTimeout. 
        /// It works likes socket-recv routine (explanation in body).
        /// Returns:
        ///    totalReceived - bytes, 
        ///    TimeoutException,
        ///    -1 in non-ComPortNum Exception  
        /// </summary>
        /// <param name="buffer"></param>
        /// <param name="maxLen"></param>
        /// <returns></returns>
        public int Recv(byte[] buffer, int maxLen)
            /// The routine works in "pseudo-blocking" mode. It cycles up to first 
            /// data received using BaseStream.ReadTimeout = TimeOutSpan (2 ms).
            /// If no any message received during ReceiveTimeout property, 
            /// the routine throws TimeoutException 
            /// In other hand, if any data has received, first no-data cycle
            /// causes to exit from routine.

            int TimeOutSpan = 2;
            // counts delay in TimeOutSpan-s after end of data to break receive
            int EndOfDataCnt;
            // pseudo-blocking timeout counter
            int TimeOutCnt = _tickCount + _receiveTimeout; 
            //number of currently received data bytes
            int justReceived = 0;
            //number of total received data bytes
            int totalReceived = 0;

            BaseStream.ReadTimeout = TimeOutSpan;
            //causes (2+1)*TimeOutSpan delay after end of data in UART stream
            EndOfDataCnt = 2;
            while (_tickCount < TimeOutCnt && EndOfDataCnt > 0)
                    justReceived = 0; 
                    justReceived = base.BaseStream.Read(buffer, totalReceived, maxLen - totalReceived);
                    totalReceived += justReceived;

                    if (totalReceived >= maxLen)
                catch (TimeoutException)
                    if (totalReceived > 0) 
                catch (Exception ex)
                    totalReceived = -1;
                    Console.WriteLine("Recv exception: " + ex);

            } //while
            if (totalReceived == 0)
                throw new TimeoutException();
                return totalReceived;
        } // Recv()            
    } // Uart

swift 3.0 Data to String?

You can also use let data = String(decoding: myStr, as: UTF8.self) here is a resource about converting data to string

How to open a workbook specifying its path

You can also open a required file through a prompt, This helps when you want to select file from different path and different file.

Sub openwb()
Dim wkbk As Workbook
Dim NewFile As Variant

NewFile = Application.GetOpenFilename("microsoft excel files (*.xlsm*), *.xlsm*")

If NewFile <> False Then
Set wkbk = Workbooks.Open(NewFile)
End If
End Sub

Getting All Variables In Scope

No. "In scope" variables are determined by the "scope chain", which is not accessible programmatically.

For detail (quite a lot of it), check out the ECMAScript (JavaScript) specification. Here's a link to the official page where you can download the canonical spec (a PDF), and here's one to the official, linkable HTML version.

Update based on your comment to Camsoft

The variables in scope for your event function are determined by where you define your event function, not how they call it. But, you may find useful information about what's available to your function via this and arguments by doing something along the lines of what KennyTM pointed out (for (var propName in ____)) since that will tell you what's available on various objects provided to you (this and arguments; if you're not sure what arguments they give you, you can find out via the arguments variable that's implicitly defined for every function).

So in addition to whatever's in-scope because of where you define your function, you can find out what else is available by other means by doing:

var n, arg, name;
alert("typeof this = " + typeof this);
for (name in this) {
    alert("this[" + name + "]=" + this[name]);
for (n = 0; n < arguments.length; ++n) {
    arg = arguments[n];
    alert("typeof arguments[" + n + "] = " + typeof arg);
    for (name in arg) {
        alert("arguments[" + n + "][" + name + "]=" + arg[name]);

(You can expand on that to get more useful information.)

Instead of that, though, I'd probably use a debugger like Chrome's dev tools (even if you don't normally use Chrome for development) or Firebug (even if you don't normally use Firefox for development), or Dragonfly on Opera, or "F12 Developer Tools" on IE. And read through whatever JavaScript files they provide you. And beat them over the head for proper docs. :-)

How to change UIButton image in Swift

Swift 5

yourButton.setImage(UIImage(named: "BUTTON_FILENAME.png"), for: .normal)

Get The Current Domain Name With Javascript (Not the path, etc.)

Combining a few answers from the above, the following works really well for me for destroying Cookies:

   * Utility method to obtain the domain URI:
  fetchDomainURI() {
    if (window.location.port.length > 0) {
      return window.location.hostname;
    return `.${window.location.hostname.match(/\w*\.\w*$/gi)[0]}`;

Works for IP addresses with ports, e.g., etc, as well as complex domains like returning => allows for cross-domain Cookie setting and destroying.

Running an outside program (executable) in Python?

If using Python 2.7 or higher (especially prior to Python 3.5) you can use the following:

import subprocess
  •, *, stdin=None, stdout=None, stderr=None, shell=False) Runs the command described by args. Waits for command to complete, then returns the returncode attribute.
  • subprocess.check_call(args, *, stdin=None, stdout=None, stderr=None, shell=False) Runs command with arguments. Waits for command to complete. If the return code was zero then returns, otherwise raises CalledProcessError. The CalledProcessError object will have the return code in the returncode attribute

Example: subprocess.check_call([r"C:\pathToYourProgram\yourProgram.exe", "your", "arguments", "comma", "separated"])

In regular Python strings, the \U character combination signals a extended Unicode code point escape.

Here is the link to the documentation:

For Python 3.5+ you can now use run() in many cases:

JavaScript vs for

For in loops on Arrays is not compatible with Prototype. If you think you might need to use that library in the future, it would make sense to stick to for loops.

how to get file path from sd card in android

this code helps to get it easily............

Actually in some devices external sdcard default name is showing as extSdCard and for other it is sdcard1. This code snippet helps to find out that exact path and helps to retrive you the path of external device..

String sdpath,sd1path,usbdiskpath,sd0path; 

if(new File("/storage/extSdCard/").exists()) 
  Log.i("Sd Cardext Path",sdpath); 
if(new File("/storage/sdcard1/").exists()) 
  Log.i("Sd Card1 Path",sd1path); 
if(new File("/storage/usbcard1/").exists()) 
  Log.i("USB Path",usbdiskpath); 
if(new File("/storage/sdcard0/").exists()) 
  Log.i("Sd Card0 Path",sd0path); 

HTML table with horizontal scrolling (first column fixed)

How about:

table {_x000D_
  table-layout: fixed; _x000D_
  width: 100%;_x000D_
  *margin-left: -100px; /*ie7*/_x000D_
td, th {_x000D_
  vertical-align: top;_x000D_
  border-top: 1px solid #ccc;_x000D_
  padding: 10px;_x000D_
  width: 100px;_x000D_
.fix {_x000D_
  position: absolute;_x000D_
  *position: relative; /*ie7*/_x000D_
  margin-left: -100px;_x000D_
  width: 100px;_x000D_
.outer {_x000D_
  position: relative;_x000D_
.inner {_x000D_
  overflow-x: scroll;_x000D_
  overflow-y: visible;_x000D_
  width: 400px; _x000D_
  margin-left: 100px;_x000D_
<div class="outer">_x000D_
  <div class="inner">_x000D_
        <th class=fix></th>_x000D_
        <th>Col 1</th>_x000D_
        <th>Col 2</th>_x000D_
        <th>Col 3</th>_x000D_
        <th>Col 4</th>_x000D_
        <th class="fix">Col 5</th>_x000D_
        <th class=fix>Header A</th>_x000D_
        <td>col 1 - A</td>_x000D_
        <td>col 2 - A (WITH LONGER CONTENT)</td>_x000D_
        <td>col 3 - A</td>_x000D_
        <td>col 4 - A</td>_x000D_
        <td class=fix>col 5 - A</td>_x000D_
        <th class=fix>Header B</th>_x000D_
        <td>col 1 - B</td>_x000D_
        <td>col 2 - B</td>_x000D_
        <td>col 3 - B</td>_x000D_
        <td>col 4 - B</td>_x000D_
        <td class=fix>col 5 - B</td>_x000D_
        <th class=fix>Header C</th>_x000D_
        <td>col 1 - C</td>_x000D_
        <td>col 2 - C</td>_x000D_
        <td>col 3 - C</td>_x000D_
        <td>col 4 - C</td>_x000D_
        <td class=fix>col 5 - C</td>_x000D_

You can test it out in this jsbin:

GET and POST methods with the same Action name in the same Controller

Since you cannot have two methods with the same name and signature you have to use the ActionName attribute:

public ActionResult Index()
  // your code
  return View();

public ActionResult IndexPost()
  // your code
  return View();

Also see "How a Method Becomes An Action"

Link a photo with the cell in excel

Select both the column you are sorting, and the column that the picture is in (I am assuming the picture is small compared to the cell, i.e. it is "in" the cell). Make sure that the object positioning property is set as "move but don't size with cells". Now if you do a sort, the pictures will move with the list being sorted.

Note - you must include the column with the picture in your range when you sort, and the picture must fit inside the cell.

The following VBA snippet will make sure all pictures in your spreadsheet have their "move and size" property set:

Sub moveAndSize()
Dim s As Shape
For Each s In ActiveSheet.Shapes
  If s.Type = msoPicture Or s.Type = msoLinkedPicture Or s.Type = msoPlaceholder Then
    s.Placement = xlMove
  End If
End Sub

If you want to make sure the picture continues to fit after you move it, you can use xlMoveAndSize instead of xlMove.

Regex to get the words after matching string

This is a Python solution.

import re

line ="""Subject:
    Security ID:        S-1-5-21-3368353891-1012177287-890106238-22451
    Account Name:       ChamaraKer
    Account Domain:     JIC
    Logon ID:       0x1fffb

    Object Server:  Security
    Object Type:    File
    Object Name:    D:\ApacheTomcat\apache-tomcat-6.0.36\logs\localhost.2013-07-01.log
    Handle ID:  0x11dc"""

regex = (r'Object Name:\s+(.*)')
match1= re.findall(regex,line)
print (match1)

*** Remote Interpreter Reinitialized  ***

Go install fails with error: no install location for directory xxx outside GOPATH

In my case (OS X) it was because I have set GOPATH to /home/username/go (as per the book) instead of /Users/username/go

Linux c++ error: undefined reference to 'dlopen'

I was using CMake to compile my project and I've found the same problem.

The solution described here works like a charm, simply add ${CMAKE_DL_LIBS} to the target_link_libraries() call

Which characters make a URL invalid?

I am implementing old http (0.9, 1.0, 1.1) request and response reader/writer. Request URI is the most problematic place.

You can't just use RFC 1738, 2396 or 3986 as it is. There are many old HTTP clients and servers that allows more characters. So I've made research based on accidentally published webserver access logs: "GET URI HTTP/1.0" 200.

I've found that the following non-standard characters are often used in URI:

\ { } < > | ` ^ "

These characters were described in RFC 1738 as unsafe.

If you want to be compatible with all old HTTP clients and servers - you have to allow these characters in request URI.

Please read more information about this research in oghttp-request-collector.

Trying to embed newline in a variable in bash

There are three levels at which a newline could be inserted in a variable.
Well ..., technically four, but the first two are just two ways to write the newline in code.

1.1. At creation.

The most basic is to create the variable with the newlines already.
We write the variable value in code with the newlines already inserted.

$ var="a
> b
> c"
$ echo "$var"

Or, inside an script code:


Yes, that means writing Enter where needed in the code.

1.2. Create using shell quoting.

The sequence $' is an special shell expansion in bash and zsh.


The line is parsed by the shell and expanded to « var="anewlinebnewlinec" », which is exactly what we want the variable var to be.
That will not work on older shells.

2. Using shell expansions.

It is basically a command expansion with several commands:

  1. echo -e

    var="$( echo -e "a\nb\nc" )"
  2. The bash and zsh printf '%b'

    var="$( printf '%b' "a\nb\nc" )"
  3. The bash printf -v

    printf -v var '%b' "a\nb\nc"
  4. Plain simple printf (works on most shells):

    var="$( printf 'a\nb\nc' )"

3. Using shell execution.

All the commands listed in the second option could be used to expand the value of a var, if that var contains special characters.
So, all we need to do is get those values inside the var and execute some command to show:

var="a\nb\nc"                 # var will contain the characters \n not a newline.

echo -e "$var"                # use echo.
printf "%b" "$var"            # use bash %b in printf.
printf "$var"                 # use plain printf.

Note that printf is somewhat unsafe if var value is controlled by an attacker.

Why use sys.path.append(path) instead of sys.path.insert(1, path)?

If you have multiple versions of a package / module, you need to be using virtualenv (emphasis mine):

virtualenv is a tool to create isolated Python environments.

The basic problem being addressed is one of dependencies and versions, and indirectly permissions. Imagine you have an application that needs version 1 of LibFoo, but another application requires version 2. How can you use both these applications? If you install everything into /usr/lib/python2.7/site-packages (or whatever your platform’s standard location is), it’s easy to end up in a situation where you unintentionally upgrade an application that shouldn’t be upgraded.

Or more generally, what if you want to install an application and leave it be? If an application works, any change in its libraries or the versions of those libraries can break the application.

Also, what if you can’t install packages into the global site-packages directory? For instance, on a shared host.

In all these cases, virtualenv can help you. It creates an environment that has its own installation directories, that doesn’t share libraries with other virtualenv environments (and optionally doesn’t access the globally installed libraries either).

That's why people consider insert(0, to be wrong -- it's an incomplete, stopgap solution to the problem of managing multiple environments.

How to create multidimensional array

I know this is ancient but what about...

4x4 example (actually 4x<anything>):

var matrix = [ [],[],[],[] ]

which can filled by:

for (var i=0; i<4; i++) {
   for (var j=0; j<4; j++) {
      matrix[i][j] = i*j;

MATLAB error: Undefined function or method X for input arguments of type 'double'

The most common cause of this problem is that Matlab cannot find the file on it's search path. Basically, Matlab looks for files in:

  1. The current directory (pwd);
  2. Directly in a directory on the path (to see the path, type path at the command line)
  3. In a directory named @(whatever the class of the first argument is) that is in any directory above.

    As someone else suggested, you can use the command which, but that is often unhelpful in this case - it tells you Matlab can't find the file, which you knew already.

    So the first thing to do is make sure the file is locatable on the path.

    Next thing to do is make sure that the file that matlab is finding (use which) requires the same type as the first argument you are actually passing. I.el, If w is supposed to be different class, and there is a divrat function there, but w is actually empty, [], so matlab is looking for Double/divrat, when there is only a @(yourclass)/divrat. This is just speculation on my part, but this often bites me.

Refused to execute script, strict MIME type checking is enabled?

I hade same problem then i fixed like this

change "text/javascript"



DOM element to corresponding vue.js component

If you want listen an event (i.e OnClick) on an input with "demo" id, you can use:

new Vue({
  el: '#demo',
  data: {
    n: 0
  methods: {
   onClick: function (e) {
     console.log( // "A"
     console.log(e.targetVM === this) // true

How to get summary statistics by group

after 5 long years I'm sure not much attention is going to be received for this answer, But still to make all options complete, here is the one with data.table

setDT(df)[ , list(mean_gr = mean(dt), sum_gr = sum(dt)) , by = .(group)]
#   group mean_gr sum_gr
#1:     A      61    244
#2:     B      66    396
#3:     C      68    408
#4:     D      61    488 

SQL Error with Order By in Subquery

On possible needs to order a subquery is when you have a UNION :

You generate a call book of all teachers and students.

SELECT name, phone FROM teachers
SELECT name, phone FROM students

You want to display it with all teachers first, followed by all students, both ordered by. So you cant apply a global order by.

One solution is to include a key to force a first order by, and then order the names :

SELECT name, phone, 1 AS orderkey FROM teachers
SELECT name, phone, 2 AS orderkey FROM students
ORDER BY orderkey, name

I think its way more clear than fake offsetting subquery result.

Exception of type 'System.OutOfMemoryException' was thrown. Why?

It runs successfully the first time, but if I run it again, I keep getting a System.OutOfMemoryException. What are some reasons this could be happening?

Regardless of what the others have said, the error has nothing to do with forgetting to dispose your DBCommand or DBConnection, and you will not fix your error by disposing of either of them.

The error has everything to do with your dataset which contains nearly 600,000 rows of data. Apparently your dataset consumes more than 50% of the available memory on your machine. Clearly, you'll run out of memory when you return another dataset of the same size before the first one has been garbage collected. Simple as that.

You can remedy this problem in a few ways:

  • Consider returning fewer records. I personally can't imagine a time when returning 600K records has ever been useful to a user. To minimize the records returned, try:

    • Limiting your query to the first 1000 records. If there are more than 1000 results returned from the query, inform the user to narrow their search results.

    • If your users really insist on seeing that much data at once, try paging the data. Remember: Google never shows you all 22 bajillion results of a search at once, it shows you 20 or so records at a time. Google probably doesn't hold all 22 bajillion results in memory at once, it probably finds its more memory efficient to requery its database to generate a new page.

  • If you just need to iterate through the data and you don't need random access, try returning a datareader instead. A datareader only loads one record into memory at a time.

If none of those are an option, then you need to force .NET to free up the memory used by the dataset before calling your method using one of these methods:

  • Remove all references to your old dataset. Anything holding on to a refenence of your dataset will prevent it from being reclaimed by memory.

  • If you can't null all the references to your dataset, clear all of the rows from the dataset and any objects bound to those rows instead. This removes references to the datarows and allows them to be eaten by the garbage collector.

I don't believe you'll need to call GC.Collect() to force a gen cycle. Not only is it generally a bad idea to call GC.Collect(), because sufficient memory pressure will cause .NET invoke the garbage collector on its own.

Note: calling Dispose on your dataset does not free any memory, nor does it invoke the garbage collector, nor does it remove a reference to your dataset. Dispose is used to clean up unmanaged resources, but the DataSet does not have any unmanaged resources. It only implements IDispoable because it inherents from MarshalByValueComponent, so the Dispose method on the dataset is pretty much useless.

Pandas: how to change all the values of a column?

You can do a column transformation by using apply

Define a clean function to remove the dollar and commas and convert your data to float.

def clean(x):
    x = x.replace("$", "").replace(",", "").replace(" ", "")
    return float(x)

Next, call it on your column like this.

data['Revenue'] = data['Revenue'].apply(clean)

Is there any way of configuring Eclipse IDE proxy settings via an autoproxy configuration script?

Here is what I do. All of these instructions are based on my minimal experiences with working PACs, so YMMV.

Download your pac file via your pac URL. It's plain text and should be easy to open in a text editor.

Near the bottom, there's probably a section that says something like: return "PROXY w.x.y.z:a" where "w.x.y.z" is an ip address or username and "a" is a port number.

Write these down.

In a recent version of eclipse :

  • Go to Window -> Preferences -> General -> Network Connections=
  • Change the provider to "Manual"
  • Select the "HTTP" line and click the edit button
  • Add the IP address and port number above to the http line
  • If you have to authenticate to use the proxy,
    • select "Requires Authentication"
    • type in your username. Note that if your authentication is on a Windows domain, you might have to prepend the domain name and a backslash (\) like: MYDOMAIN\MYUSERID
    • Type in your password
  • Click OK
  • Click Apply
  • Click OK

At this point, you should be able to browse using the internal web browser (at least on http URLs).

Good luck.

Edit: Just so you know, it's WAY easier to use Nexus, one set of <mirror> tags and a single proxy setup (inside Nexus) to manage the proxy issues of Maven inside a firewall.

Unbound classpath container in Eclipse

I had a similar problem when I recreated my workspace that was fixed in the following way:

Go to Eclipse -> Preferences, under Java select "Installed JREs" and check one of the boxes to specify a default JRE. Click OK and then go back to your project's properties. Go to the "Java Build Path" section and choose the "Libraries" tab. Remove the unbound System Default library, then click the "Add Library" button. Select "JRE System Library" and you should be good to go!

Convert IQueryable<> type object to List<T> type?

The List class's constructor can convert an IQueryable for you:

public static List<TResult> ToList<TResult>(this IQueryable source)
    return new List<TResult>(source);

or you can just convert it without the extension method, of course:

var list = new List<T>(queryable);

How do I use TensorFlow GPU?

Strangely, even though the tensorflow website 1 mentions that CUDA 10.1 is compatible with tensorflow-gpu-1.13.1, it doesn't work so far. tensorflow-gpu gets installed properly though but it throws out weird errors when running.

So far, the best configuration to run tensorflow with GPU is CUDA 9.0 with tensorflow_gpu-1.12.0 under python3.6.

Following this configuration with the steps mentioned in (the answer above), worked for me :)

PostgreSQL JOIN data from 3 tables

Maybe the following is what you are looking for:

SELECT name, pathfilename
  FROM table1
  WHERE name = 'John';

How to connect HTML Divs with Lines?

You can use SVGs to connect two divs using only HTML and CSS:

<div id="div1" style="width: 100px; height: 100px; top:0; left:0; background:#777; position:absolute;"></div>
<div id="div2" style="width: 100px; height: 100px; top:300px; left:300px; background:#333; position:absolute;"></div>

(please use seperate css file for styling)

Create a svg line and use this line to connect above divs

<svg width="500" height="500"><line x1="50" y1="50" x2="350" y2="350" stroke="black"/></svg>


x1,y1 indicates center of first div and
x2,y2 indicates center of second div

You can check how it looks in the snippet below

<div id="div1" style="width: 100px; height: 100px; top:0; left:0; background:#777; position:absolute;"></div>_x000D_
<div id="div2" style="width: 100px; height: 100px; top:300px; left:300px; background:#333; position:absolute;"></div>_x000D_
<svg width="500" height="500"><line x1="50" y1="50" x2="350" y2="350" stroke="black"/></svg>

jQuery Ajax error handling, show custom exception messages

This is probably caused by the JSON field names not having quotation marks.

Change the JSON structure from:




How can I read and parse CSV files in C++?

I wrote a header-only, C++11 CSV parser. It's well tested, fast, supports the entire CSV spec (quoted fields, delimiter/terminator in quotes, quote escaping, etc.), and is configurable to account for the CSVs that don't adhere to the specification.

Configuration is done through a fluent interface:

// constructor accepts any input stream
CsvParser parser = CsvParser(std::cin)
  .delimiter(';')    // delimited by ; instead of ,
  .quote('\'')       // quoted fields use ' instead of "
  .terminator('\0'); // terminated by \0 instead of by \r\n, \n, or \r

Parsing is just a range based for loop:

#include <iostream>
#include "../parser.hpp"

using namespace aria::csv;

int main() {
  std::ifstream f("some_file.csv");
  CsvParser parser(f);

  for (auto& row : parser) {
    for (auto& field : row) {
      std::cout << field << " | ";
    std::cout << std::endl;

OS X: equivalent of Linux's wget

wget Precompiled Mac Binary

For those looking for a quick wget install on Mac, check out Quentin Stafford-Fraser's precompiled binary here, which has been around for over a decade:

MD5 for 2008 24a35d499704eecedd09e0dd52175582
MD5 for 2005 c7b48ec3ff929d9bd28ddb87e1a76ffb

No make/install/port/brew/curl junk. Just download, install, and run. Works with Mac OS X 10.3-10.12+.

Is there a better way to do optional function parameters in JavaScript?

Your logic fails if optionalArg is passed, but evaluates as false - try this as an alternative

if (typeof optionalArg === 'undefined') { optionalArg = 'default'; }

Or an alternative idiom:

optionalArg = (typeof optionalArg === 'undefined') ? 'default' : optionalArg;

Use whichever idiom communicates the intent best to you!

Passing an array of data as an input parameter to an Oracle procedure

If the types of the parameters are all the same (varchar2 for example), you can have a package like this which will do the following:


   TYPE assoc_array_varchar2_t IS TABLE OF VARCHAR2(4000) INDEX BY BINARY_INTEGER;

   PROCEDURE your_proc(p_parm IN assoc_array_varchar2_t);

END test_pkg;


   PROCEDURE your_proc(p_parm IN assoc_array_varchar2_t) AS
      FOR i IN p_parm.first .. p_parm.last
      END LOOP;


END test_pkg;

Then, to call it you'd need to set up the array and pass it:

  l_array testuser.test_pkg.assoc_array_varchar2_t;
  l_array(0) := 'hello';
  l_array(1) := 'there';  


How do I combine a background-image and CSS3 gradient on the same element?

I wanted to make span button with background image, background gradient combination. helped to do my work task. Only I have to remove some auto generated additional CSS. But it's really nice site build your scratch work.

#nav span {
    background: url("../images/order-now-mobile.png"), -webkit-linear-gradient(0deg, rgba(190,20,27,1) 0, rgba(224,97,102,1) 51%, rgba(226,0,0,1) 100%);
    background: url("../images/order-now-mobile.png"), -moz-linear-gradient(90deg, rgba(190,20,27,1) 0, rgba(224,97,102,1) 51%, rgba(226,0,0,1) 100%);
    background: url("../images/order-now-mobile.png"), linear-gradient(90deg, rgba(170,31,0,1) 0, rgba(214,18,26,1) 51%, rgba(170,31,0,1) 100%);
    background-repeat: no-repeat;
    background-position: 50% 50%;
    border-radius: 8px;
    border: 3px solid #b30a11;

how to check and set max_allowed_packet mysql variable

max_allowed_packet is set in mysql config, not on php side


You can see it's curent value in mysql like this:

SHOW VARIABLES LIKE 'max_allowed_packet';

You can try to change it like this, but it's unlikely this will work on shared hosting:

SET GLOBAL max_allowed_packet=16777216;

You can read about it here


The [mysqld] is necessary to make the max_allowed_packet working since at least mysql version 5.5.

Recently setup an instance on AWS EC2 with Drupal and Solr Search Engine, which required 32M max_allowed_packet. It you set the value under [mysqld_safe] (which is default settings came with the mysql installation) mode in /etc/my.cnf, it did no work. I did not dig into the problem. But after I change it to [mysqld] and restarted the mysqld, it worked.

VB.Net Properties - Public Get, Private Set

One additional tweak worth mentioning: I'm not sure if this is a .NET 4.0 or Visual Studio 2010 feature, but if you're using both you don't need to declare the value parameter for the setter/mutator block of code:

Private _name As String

Public Property Name() As String
        Return _name
    End Get
    Private Set
        _name = value
    End Set
End Property

How to export a table dataframe in PySpark to csv?

If you cannot use spark-csv, you can do the following: x: ",".join(map(str, x))).coalesce(1).saveAsTextFile("file.csv")

If you need to handle strings with linebreaks or comma that will not work. Use this:

import csv
import cStringIO

def row2csv(row):
    buffer = cStringIO.StringIO()
    writer = csv.writer(buffer)
    writer.writerow([str(s).encode("utf-8") for s in row])

Keyboard shortcut to paste clipboard content into command prompt window (Win XP)

Thanks Pablo, just what I was looking for! However, if I can take the liberty of improving your script slightly, I suggest replacing your ^V macro with the following:

; Use backslash instead of backtick (yes, I am a C++ programmer).
#EscapeChar \

; Paste in command window.
StringReplace clipboard2, clipboard, \r\n, \n, All
SendInput {Raw}%clipboard2%

The advantage of using SendInput is that

  • it doesn't rely on the command prompt system menu having an "Alt+Space E P" menu item to do the pasting (works for English and Spanish, but not for all languages).
  • it avoids that nasty flicker you get as the menu is created and destroyed.

Note, it's important to include the "{Raw}" in the SendInput command, in case the clipboard happens to contain "!", "+", "^" or "#".

Note, it uses StringReplace to remove excess Windows carriage return characters. Thanks hugov for that suggestion!

Android EditText view Floating Hint in Material Design

Floating hint EditText:

Add below dependency in gradle:

compile ''

In layout:



Escape double quotes for JSON in Python

Why not do string suppression with triple quotes:

>>> s = """my string with "some" double quotes"""
>>> print s
my string with "some" double quotes

Re-assign host access permission to MySQL user

I haven't had to do this, so take this with a grain of salt and a big helping of "test, test, test".

What happens if (in a safe controlled test environment) you directly modify the Host column in the mysql.user and probably mysql.db tables? (E.g., with an update statement.) I don't think MySQL uses the user's host as part of the password encoding (the PASSWORD function doesn't suggest it does), but you'll have to try it to be sure. You may need to issue a FLUSH PRIVILEGES command (or stop and restart the server).

For some storage engines (MyISAM, for instance), you may also need to check/modify the .frm file any views that user has created. The .frm file stores the definer, including the definer's host. (I have had to do this, when moving databases between hosts where there had been a misconfiguration causing the wrong host to be recorded...)

Excel VBA Open a Folder

If you want to open a windows file explorer, you should call explorer.exe

Call Shell("explorer.exe" & " " & "P:\Engineering", vbNormalFocus)

Equivalent syxntax

Shell "explorer.exe" & " " & "P:\Engineering", vbNormalFocus

How to Decrease Image Brightness in CSS

-webkit-filter: brightness(0.50);

I've got this cool solution:

PHP header redirect 301 - what are the implications?

The effect of the 301 would be that the search engines will index /option-a instead of /option-x. Which is probably a good thing since /option-x is not reachable for the search index and thus could have a positive effect on the index. Only if you use this wisely ;-)

After the redirect put exit(); to stop the rest of the script to execute

header("HTTP/1.1 301 Moved Permanently"); 
header("Location: /option-a"); 

Killing a process using Java

You can kill a (SIGTERM) a windows process that was started from Java by calling the destroy method on the Process object. You can also kill any child Processes (since Java 9).

The following code starts a batch file, waits for ten seconds then kills all sub-processes and finally kills the batch process itself.

ProcessBuilder pb = new ProcessBuilder("cmd /c my_script.bat"));
Process p = pb.start();
p.waitFor(10, TimeUnit.SECONDS);

p.descendants().forEach(ph -> {


Difference between Parameters.Add(string, object) and Parameters.AddWithValue

There is no difference in terms of functionality

The addwithvalue method takes an object as the value. There is no type data type checking. Potentially, that could lead to error if data type does not match with SQL table. The add method requires that you specify the Database type first. This helps to reduce such errors.

For more detail Please click here

How to edit incorrect commit message in Mercurial?

Rollback-and-reapply is realy simple solution, but it can help only with the last commit. Mercurial Queues is much more powerful thing (note that you need to enable Mercurial Queues Extension in order to use "hg q*" commands).

Parsing JSON using C

cJSON has a decent API and is small (2 files, ~700 lines). Many of the other JSON parsers I looked at first were huge... I just want to parse some JSON.

Edit: We've made some improvements to cJSON over the years.

How to select an item from a dropdown list using Selenium WebDriver with java?

Use -

new Select(driver.findElement("gender"))).selectByVisibleText("Germany");

Of course, you need to import;

How do I save a stream to a file in C#?

public void CopyStream(Stream stream, string destPath)
  using (var fileStream = new FileStream(destPath, FileMode.Create, FileAccess.Write))

Could not open input file: composer.phar

I have fixed the same issue with below steps

  1. Open project directory Using Terminal (which you are using i.e. mintty )
  2. Now install composer within this directory as per given directions on

php -r "copy('', 'composer-setup.php');"

php -r "if (hash_file('SHA384', 'composer-setup.php') === 'the-provided-hash-code') { echo 'Installer verified'; } else { echo 'Installer corrupt'; unlink('composer-setup.php'); } echo PHP_EOL;"

php composer-setup.php php -r "unlink('composer-setup.php');"

  1. Now run your command.

Everything is working fine now because the composer.phar file is available within the current project directory.

Copied from


How do I read an attribute on a class at runtime?

In case anyone needs a nullable result and for this to work across Enums, PropertyInfo and classes, here's how I solved it. This is a modification of Darin Dimitrov's updated solution.

public static object GetAttributeValue<TAttribute, TValue>(this object val, Func<TAttribute, TValue> valueSelector) where TAttribute : Attribute
        Type t = val.GetType();
        TAttribute attr;
        if (t.IsEnum && t.GetField(val.ToString()).GetCustomAttributes(typeof(TAttribute), true).FirstOrDefault() is TAttribute att)
            // Applies to Enum values
            attr = att;
        else if (val is PropertyInfo pi && pi.GetCustomAttributes(typeof(TAttribute), true).FirstOrDefault() is TAttribute piAtt)
            // Applies to Properties in a Class
            attr = piAtt;
            // Applies to classes
            attr = (TAttribute)t.GetCustomAttributes(typeof(TAttribute), false).FirstOrDefault();
        return valueSelector(attr);
        return null;

Usage examples:

// Class
SettingsEnum.SettingGroup settingGroup = (SettingsEnum.SettingGroup)(this.GetAttributeValue((SettingGroupAttribute attr) => attr.Value) as SettingsEnum.SettingGroup?);

// Enum
DescriptionAttribute desc = settingGroup.GetAttributeValue((DescriptionAttribute attr) => attr) as DescriptionAttribute;

// PropertyInfo       
foreach (PropertyInfo pi in this.GetType().GetProperties())
    string setting = ((SettingsEnum.SettingName)(pi.GetAttributeValue((SettingNameAttribute attr) => attr.Value) as SettingsEnum.SettingName?)).ToString();

Open file by its full path in C++

A different take on this question, which might help someone:

I came here because I was debugging in Visual Studio on Windows, and I got confused about all this / vs \\ discussion (it really should not matter in most cases).

For me, the problem was: the "current directory" was not set to what I wanted in Visual Studio. It defaults to the directory of the executable (depending on how you set up your project).

Change it via: Right-click the solution -> Properties -> Working Directory

I only mention it because the question seems Windows-centric, which generally also means VisualStudio-centric, which tells me this hint might be relevant (:

Python regex findall

Use this pattern,

pattern = '\[P\].+?\[\/P\]'

Check here

PHP : send mail in localhost

try this

$headers = "MIME-Version: 1.0" . "\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1" . "\r\n";
$headers .= "From: [email protected]" . "\r\n";
mail("[email protected]","test subject","test body",$headers);

jsPDF multi page PDF with HTML renderer

Below is my code but the problem is that the document doesn't split to display the other part of the document in a new page.

Please improve this code.

<script type='text/javascript'>
$(document).on("click", "#btnExportToPDF", function () {
    var table1 =
    cellWidth =42,
    rowCount = 0,
    leftMargin = 2,
    topMargin = 12,
    topMarginTable =5,
    headerRowHeight = 13,
    rowHeight = 12,
    l = {
        orientation: 'p',
        unit: 'mm',
        format: 'a3',
        compress: true,
        fontSize: 11,
        lineHeight: 1,
        autoSize: false,
        printHeaders: true

    var doc = new jsPDF(l,'pt', 'letter');

        title: 'Test PDF Document',
        subject: 'This is the subject',
        author: 'author',
        keywords: 'generated, javascript, web 2.0, ajax',
        creator: 'author'

    $.each(table1, function (i, row)

        $.each(row, function (j, cellContent) {

            if (rowCount == 1) {
                doc.margins = 1;
                doc.setFont("Times New Roman");

                doc.cell(leftMargin, topMargin, cellWidth, headerRowHeight, cellContent, i)
            else if (rowCount == 2) {

                doc.margins = 1;
                doc.setFont("Times ");
                // or for normal font type use ------ doc.setFontType("normal");


                doc.cell(leftMargin, topMargin, cellWidth, rowHeight, cellContent, i);
            else {

                doc.margins = 1;
                doc.setFont("Times  ");
                doc.setFontType("normal ");
                doc.cell(leftMargin, topMargin, cellWidth, rowHeight, cellContent, i);
                // 1st=left margin    2nd parameter=top margin,     3rd=row cell width      4th=Row height
    })'sample Report.pdf');

function tableToJson(table) {

    var data = [];

    // first row needs to be headers
    var headers = [];

    for (var i=0; i<table.rows[0].cells.length; i++) {
        headers[i] = table.rows[0].cells[i].innerHTML.toLowerCase().replace(/ /gi,'');

    // go through cells
    for (var i=1; i<table.rows.length; i++) {

        var tableRow = table.rows[i];

        var rowData = {};

        for (var j=0; j<tableRow.cells.length; j++) {
            rowData[ headers[j] ] = tableRow.cells[j].innerHTML;


    return data;

What is the use of the @Temporal annotation in Hibernate?

If you're looking for short answer:

In the case of using java.util.Date, Java doesn't really know how to directly relate to SQL types. This is when @Temporal comes into play. It's used to specify the desired SQL type.

Source: Baeldung

How do I prevent the error "Index signature of object type implicitly has an 'any' type" when compiling typescript with noImplicitAny flag enabled?

At today better solution is to declare types. Like

enum SomeObjectKeys {
    firstKey = 'firstKey',
    secondKey = 'secondKey',
    thirdKey = 'thirdKey',

let someObject: Record<SomeObjectKeys, string> = {
    firstKey:   'firstValue',
    secondKey:  'secondValue',
    thirdKey:   'thirdValue',

let key: SomeObjectKeys = 'secondKey';

let secondValue: string = someObject[key];

Meaning of tilde in Linux bash (not home directory)

Are they the home directories of users in /etc/passwd? Services like postgres, sendmail, apache, etc., create system users that have home directories just like normal users.

How to get object length

If you want to avoid new dependencies you could make your own smart objects. Of course only if you want to do more that just get it's size.

MyNeatObj = function (obj) {
  var length = null;

  this.size = function () {
    if (length === null) {
      length = 0;
      for (var key in obj) length++;
    return length;

var thingy = new MyNeatObj(originalObj);

How to split page into 4 equal parts?

I did not want to add style to <body> tag and <html> tag.

    width: 100%;
    height: 100vh;
    margin: 0;
    padding: 0;

    width: 100%;
    height: 50vh;

    display: inline;
    float: left;
    width: 50%;
    height: 100%;

    top: 0;
    left: 50vh;
    background-color: red;

    top: 0;
    left: 0;
    background-color: yellow;

    top: 50vw;
    left: 0;
    background-color: blue;

    top: 50vw;
    left: 50vh;
    background-color: green;
<!DOCTYPE html>
<html lang="en">
    <meta charset="UTF-8">
    <link type="text/css" rel="stylesheet" href="main.css" />

<div class='quodrant'>
    <div class='qtop'>
        <div class='quodrant1'></div>
        <div class='quodrant2'></div>
    <div class='qbottom'>
        <div class='quodrant3'></div>
        <div class='quodrant4'></div>

<script type="text/javascript" src="main.js"></script>

Or making it looks nicer.

    width: 100%;
    height: 100vh;
    margin: 0;
    padding: 0;

    width: 96%;
    height: 46vh;

    display: inline;
    float: left;
    width: 46%;
    height: 96%;
    border-radius: 30px;
    margin: 2%;

    background-color: #948be5;

    background-color: #22e235;

    background-color: #086e75;

    background-color: #7cf5f9;
<!DOCTYPE html>
<html lang="en">
    <meta charset="UTF-8">
    <link type="text/css" rel="stylesheet" href="main.css" />

<div class='quodrant'>
    <div class='qtop'>
        <div class='quodrant1'></div>
        <div class='quodrant2'></div>
    <div class='qbottom'>
        <div class='quodrant3'></div>
        <div class='quodrant4'></div>

<script type="text/javascript" src="main.js"></script>

jQuery get value of select onChange


    jQuery("#id").change(function() {
      var value = jQuery(this).children(":selected").attr("value");


How to echo in PHP, HTML tags

This will also work fine with double quotes. To echo any html_tag with double quotes we just need to remember one thing, Do not use any other double quotes(") in the middle.

    echo "
        <h3><a href=''>First</a></h3>
        <div>Lorem ipsum dolor sit amet.</div>

Notice here the link inside the PHP echo is enclosed within the single quotes. This is the precaution you should take while using the double quotes for this purpose.

AmazonS3 putObject with InputStream length example

I've created a library that uses multipart uploads in the background to avoid buffering everything in memory and also doesn't write to disk:

Swift - iOS - Dates and times in different format

Current date time to formated string:

let currentDate = Date()
let dateFormatter = DateFormatter()

dateFormatter.dateFormat = "dd/MM/yyyy hh:mm:ss a"
let convertedDate: String = dateFormatter.string(from: currentDate) //08/10/2016 01:42:22 AM

More Date Time Formats

How do I combine two lists into a dictionary in Python?

>>> dict(zip([1, 2, 3, 4], ['a', 'b', 'c', 'd']))
{1: 'a', 2: 'b', 3: 'c', 4: 'd'}

If they are not the same size, zip will truncate the longer one.

How to cache Google map tiles for offline usage?

If you are trying to cache the tiles that Google serves, that may be a violation of Google's Terms of Service (unless, under certain circumstances, if you've purchased their enterprise Maps API Premier). That's why gmapcatcher has it crossed off their list. See

At the gmapcatcher URL above, you will also find a shell script that can download tiles (or so its author says).

There are also other projects that try to make Google Maps available offline:

Lastly, if Google Earth can meet your needs, then you can use that. Offline usage of Google Earth requires a Google Earth Enterprise license according to

Note that the preceding page also says: "You may not scrape or otherwise export Content from Google Maps or Earth or save it for offline use." So if you try to cache tiles, that will almost certainly be considered (by Google, anyway) a violation of the Terms of Service.

Best GUI designer for eclipse?

Look at my plugin for developing swing application. It is as easy as that of netbeans':

What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?

Besides what has been suggested, I'd like to post the source code related to SynchronizedMap.

To make a Map thread safe, we can use Collections.synchronizedMap statement and input the map instance as the parameter.

The implementation of synchronizedMap in Collections is like below

   public static <K,V> Map<K,V> synchronizedMap(Map<K,V> m) {
        return new SynchronizedMap<>(m);

As you can see, the input Map object is wrapped by the SynchronizedMap object.
Let's dig into the implementation of SynchronizedMap ,

 private static class SynchronizedMap<K,V>
        implements Map<K,V>, Serializable {
        private static final long serialVersionUID = 1978198479659022715L;

        private final Map<K,V> m;     // Backing Map
        final Object      mutex;        // Object on which to synchronize

        SynchronizedMap(Map<K,V> m) {
            this.m = Objects.requireNonNull(m);
            mutex = this;

        SynchronizedMap(Map<K,V> m, Object mutex) {
            this.m = m;
            this.mutex = mutex;

        public int size() {
            synchronized (mutex) {return m.size();}
        public boolean isEmpty() {
            synchronized (mutex) {return m.isEmpty();}
        public boolean containsKey(Object key) {
            synchronized (mutex) {return m.containsKey(key);}
        public boolean containsValue(Object value) {
            synchronized (mutex) {return m.containsValue(value);}
        public V get(Object key) {
            synchronized (mutex) {return m.get(key);}

        public V put(K key, V value) {
            synchronized (mutex) {return m.put(key, value);}
        public V remove(Object key) {
            synchronized (mutex) {return m.remove(key);}
        public void putAll(Map<? extends K, ? extends V> map) {
            synchronized (mutex) {m.putAll(map);}
        public void clear() {
            synchronized (mutex) {m.clear();}

        private transient Set<K> keySet;
        private transient Set<Map.Entry<K,V>> entrySet;
        private transient Collection<V> values;

        public Set<K> keySet() {
            synchronized (mutex) {
                if (keySet==null)
                    keySet = new SynchronizedSet<>(m.keySet(), mutex);
                return keySet;

        public Set<Map.Entry<K,V>> entrySet() {
            synchronized (mutex) {
                if (entrySet==null)
                    entrySet = new SynchronizedSet<>(m.entrySet(), mutex);
                return entrySet;

        public Collection<V> values() {
            synchronized (mutex) {
                if (values==null)
                    values = new SynchronizedCollection<>(m.values(), mutex);
                return values;

        public boolean equals(Object o) {
            if (this == o)
                return true;
            synchronized (mutex) {return m.equals(o);}
        public int hashCode() {
            synchronized (mutex) {return m.hashCode();}
        public String toString() {
            synchronized (mutex) {return m.toString();}

        // Override default methods in Map
        public V getOrDefault(Object k, V defaultValue) {
            synchronized (mutex) {return m.getOrDefault(k, defaultValue);}
        public void forEach(BiConsumer<? super K, ? super V> action) {
            synchronized (mutex) {m.forEach(action);}
        public void replaceAll(BiFunction<? super K, ? super V, ? extends V> function) {
            synchronized (mutex) {m.replaceAll(function);}
        public V putIfAbsent(K key, V value) {
            synchronized (mutex) {return m.putIfAbsent(key, value);}
        public boolean remove(Object key, Object value) {
            synchronized (mutex) {return m.remove(key, value);}
        public boolean replace(K key, V oldValue, V newValue) {
            synchronized (mutex) {return m.replace(key, oldValue, newValue);}
        public V replace(K key, V value) {
            synchronized (mutex) {return m.replace(key, value);}
        public V computeIfAbsent(K key,
                Function<? super K, ? extends V> mappingFunction) {
            synchronized (mutex) {return m.computeIfAbsent(key, mappingFunction);}
        public V computeIfPresent(K key,
                BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
            synchronized (mutex) {return m.computeIfPresent(key, remappingFunction);}
        public V compute(K key,
                BiFunction<? super K, ? super V, ? extends V> remappingFunction) {
            synchronized (mutex) {return m.compute(key, remappingFunction);}
        public V merge(K key, V value,
                BiFunction<? super V, ? super V, ? extends V> remappingFunction) {
            synchronized (mutex) {return m.merge(key, value, remappingFunction);}

        private void writeObject(ObjectOutputStream s) throws IOException {
            synchronized (mutex) {s.defaultWriteObject();}

What SynchronizedMap does can be summarized as adding a single lock to primary method of the input Map object. All method guarded by the lock can't be accessed by multiple threads at the same time. That means normal operations like put and get can be executed by a single thread at the same time for all data in the Map object.

It makes the Map object thread safe now but the performance may become an issue in some scenarios.

The ConcurrentMap is far more complicated in the implementation, we can refer to Building a better HashMap for details. In a nutshell, it's implemented taking both thread safe and performance into consideration.

failed to open stream: HTTP wrapper does not support writeable connections

Instead of doing file_put_contents(***WebSiteURL***...) you need to use the server path to /cache/lang/file.php (e.g. /home/content/site/folders/filename.php).

You cannot open a file over HTTP and expect it to be written. Instead you need to open it using the local path.

Bootstrap 4 File Input

Here is the answer with blue box-shadow,border,outline removed with file name fix in custom-file input of bootstrap appear on choose filename and if you not choose any file then show No file chosen.

    $(document).on('change', 'input[type="file"]', function (event) { _x000D_
        var filename = $(this).val();_x000D_
        if (filename == undefined || filename == ""){_x000D_
        $(this).next('.custom-file-label').html('No file chosen');_x000D_
        else _x000D_
        { $(this).next('.custom-file-label').html([0].name); }_x000D_
    input[type=file]:focus,.custom-file-input:focus~.custom-file-label {_x000D_
        border-color: transparent;_x000D_
        box-shadow: none!important;_x000D_
    .custom-file-input {_x000D_
        cursor: pointer;_x000D_
    <script src=""></script>_x000D_
    <link href="" rel="stylesheet"/>_x000D_
    <div class="container py-5">_x000D_
    <div class="input-group mb-3">_x000D_
      <div class="input-group-prepend">_x000D_
        <span class="input-group-text">Upload</span>_x000D_
      <div class="custom-file">_x000D_
        <input type="file" class="custom-file-input" id="inputGroupFile01">_x000D_
        <label class="custom-file-label" for="inputGroupFile01">Choose file</label>_x000D_

Command Line Tools not working - OS X El Capitan, Sierra, High Sierra, Mojave

Reassigning the path Xcode is configured with worked for me.

sudo xcode-select -switch /Applications/

You'll then likely be prompted (after trying a command) to agree to the license agreement.

How do I use SELECT GROUP BY in DataTable.Select(Expression)?

dt = dt.AsEnumerable().GroupBy(r => r.Field<int>("ID")).Select(g => g.First()).CopyToDataTable();

Java recursive Fibonacci sequence

Most of solutions offered here run in O(2^n) complexity. Recalculating identical nodes in recursive tree is inefficient and wastes CPU cycles.

We can use memoization to make fibonacci function run in O(n) time

public static int fibonacci(int n) {
    return fibonacci(n, new int[n + 1]);

public static int fibonacci(int i, int[] memo) {

    if (i == 0 || i == 1) {
        return i;

    if (memo[i] == 0) {
        memo[i] = fibonacci(i - 1, memo) + fibonacci(i - 2, memo);
    return memo[i];

If we follow Bottom-Up Dynamic Programming route, below code is simple enough to compute fibonacci:

public static int fibonacci1(int n) {
    if (n == 0) {
        return n;
    } else if (n == 1) {
        return n;
    final int[] memo = new int[n];

    memo[0] = 0;
    memo[1] = 1;

    for (int i = 2; i < n; i++) {
        memo[i] = memo[i - 1] + memo[i - 2];
    return memo[n - 1] + memo[n - 2];

filemtime "warning stat failed for"

in my case it was not related to the path or filename. If filemtime(), fileatime() or filectime() don't work, try stat().

$filedate = date_create(date("Y-m-d", filectime($file)));


$stat = stat($directory.$file);
$filedate = date_create(date("Y-m-d", $stat['ctime']));

that worked for me.

Complete snippet for deleting files by number of days:

$directory = $_SERVER['DOCUMENT_ROOT'].'/directory/';
$files = array_slice(scandir($directory), 2);
foreach($files as $file)
    $extension      = substr($file, -3, 3); 
    if ($extension == 'jpg') // in case you only want specific files deleted
        $stat = stat($directory.$file);
        $filedate = date_create(date("Y-m-d", $stat['ctime']));
        $today = date_create(date("Y-m-d"));
        $days = date_diff($filedate, $today, true);
        if ($days->days > 1)