Programs & Examples On #Dfm

Python: pandas merge multiple dataframes

Thank you for your help @jezrael, @zipa and @everestial007, both answers are what I need. If I wanted to make a recursive, this would also work as intended:

def mergefiles(dfs=[], on=''):
    """Merge a list of files based on one column"""
    if len(dfs) == 1:
         return "List only have one element."

    elif len(dfs) == 2:
        df1 = dfs[0]
        df2 = dfs[1]
        df = df1.merge(df2, on=on)
        return df

    # Merge the first and second datafranes into new dataframe
    df1 = dfs[0]
    df2 = dfs[1]
    df = dfs[0].merge(dfs[1], on=on)

    # Create new list with merged dataframe
    dfl = []

    # Join lists
    dfl = dfl + dfs[2:] 
    dfm = mergefiles(dfl, on)
    return dfm

Generate PDF from HTML using pdfMake in Angularjs

was implemented that in service-now platform. No need to use other library - makepdf have all you need!

that my html part (include preloder gif):

   <div class="pdf-preview" ng-init="generatePDF(true)">
    <object data="{{c.content}}" type="application/pdf" style="width:58vh;height:88vh;" ng-if="c.content" ></object>
    <div ng-if="!c.content">
      <img src="" width="50" height="50">

this is client script (js part)

$scope.generatePDF = function (preview) {
    docDefinition = {} //you rootine to generate pdf content
    if (preview) {
        pdfMake.createPdf(docDefinition).getDataUrl(function(dataURL) {
            c.content = dataURL;

So on page load I fire init function that generate pdf content and if required preview (set as true) result will be assigned to c.content variable. On html side object will be not shown until c.content will got a value, so that will show loading gif.

Extract / Identify Tables from PDF python

You should definitely have a look at this answer of mine:

and also have a look at all the links included therein.

Tabula/TabulaPDF is currently the best table extraction tool that is available for PDF scraping.

Extracting text from a PDF file using PDFMiner in python?

this code is tested with pdfminer for python 3 (pdfminer-20191125)

from pdfminer.layout import LAParams
from pdfminer.converter import PDFPageAggregator
from pdfminer.pdfinterp import PDFResourceManager
from pdfminer.pdfinterp import PDFPageInterpreter
from pdfminer.pdfpage import PDFPage
from pdfminer.layout import LTTextBoxHorizontal

def parsedocument(document):
    # convert all horizontal text into a lines list (one entry per line)
    # document is a file stream
    lines = []
    rsrcmgr = PDFResourceManager()
    laparams = LAParams()
    device = PDFPageAggregator(rsrcmgr, laparams=laparams)
    interpreter = PDFPageInterpreter(rsrcmgr, device)
    for page in PDFPage.get_pages(document):
            layout = device.get_result()
            for element in layout:
                if isinstance(element, LTTextBoxHorizontal):
    return lines

Content Security Policy "data" not working for base64 Images in Chrome 28

Try this

data to load:

<svg xmlns='' viewBox='0 0 4 5'><path fill='#343a40' d='M2 0L0 2h4zm0 5L0 3h4z'/></svg>

get a utf8 to base64 convertor and convert the "svg" string to:


and the CSP is

img-src data: image/svg+xml;base64,PHN2ZyB4bWxucz0naHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmcnIHZpZXdCb3g9JzAgMCA0IDUn

UnicodeDecodeError when reading CSV file in Pandas with Python

Please try to add


This will help. Worked for me. Also, make sure you're using the correct delimiter and column names.

You can start with loading just 1000 rows to load the file quickly.

Select a Column in SQL not in Group By

You can do this with PARTITION and RANK:

select * from
    select MyPK, fmgcms_cpeclaimid, createdon,  
        Rank() over (Partition BY fmgcms_cpeclaimid order by createdon DESC) as Rank
    from Filteredfmgcms_claimpaymentestimate 
    where createdon < 'reportstartdate' 
) tmp
where Rank = 1

How to convert image into byte array and byte array to base64 String in android?

Try this:

// convert from bitmap to byte array
public byte[] getBytesFromBitmap(Bitmap bitmap) {
    ByteArrayOutputStream stream = new ByteArrayOutputStream();
    bitmap.compress(CompressFormat.JPEG, 70, stream);
    return stream.toByteArray();

// get the base 64 string
String imgString = Base64.encodeToString(getBytesFromBitmap(someImg), 

How can I get the max (or min) value in a vector?

If you want to use an iterator, you can do a placement-new with an array.

std::array<int, 10> icloud = new (cloud) std::array<int,10>;

Note the lack of a () at the end, that is important. This creates an array class that uses that memory as its storage, and has STL features like iterators.

(This is C++ TR1/C++11 by the way)

How is TeamViewer so fast?

My random guess is: TV uses x264 codec which has a commercial license (otherwise TeamViewer would have to release their source code). At some point (more than 5 years ago), I recall main developer of x264 wrote an article about improvements he made for low delay encoding (if you delay by a few frames encoders can compress better), plus he mentioned some other improvements that were relevant for TeamViewer-like use. In that post he mentioned playing quake over video stream with no noticeable issues. Back then I was kind of sure who was the sponsor of these improvements, as TeamViewer was pretty much the only option at that time. x264 is an open source implementation of H264 video codec, and it's insanely good implementation, it's the best one. At the same time it's extremely well optimized. Most likely due to extremely good implementation of x264 you get much better results with TV at lower CPU load. AnyDesk and Chrome Remote Desk use libvpx, which isn't as good as x264 (optimization and video quality wise).

However, I don't think TeamView can beat microsoft's RDP. To me it's the best, however it works between windows PCs or from Mac to Windows only. TV works even from mobiles.

Update: article was written in January 2010, so that work was done roughly 10 years ago. Also, I made a mistake: he played call of duty, not quake. When you posted your question, if my guess is correct, TeamViewer had been using that work for 3 years. Read that blog post from web archive: x264: the best low-latency video streaming platform in the world. When I read the article back in 2010, I was sure that the "startup–which has requested not to be named" that the author mentions was TeamViewer.

Merging multiple PDFs using iTextSharp in

Using iTextSharp.dll

protected void Page_Load(object sender, EventArgs e)
    String[] files = @"C:\ENROLLDOCS\A1.pdf,C:\ENROLLDOCS\A2.pdf".Split(',');
    MergeFiles(@"C:\ENROLLDOCS\New1.pdf", files);
public void MergeFiles(string destinationFile, string[] sourceFiles)
    if (System.IO.File.Exists(destinationFile))

    string[] sSrcFile;
    sSrcFile = new string[2];

    string[] arr = new string[2];
    for (int i = 0; i <= sourceFiles.Length - 1; i++)
        if (sourceFiles[i] != null)
            if (sourceFiles[i].Trim() != "")
                arr[i] = sourceFiles[i].ToString();

    if (arr != null)
        sSrcFile = new string[2];

        for (int ic = 0; ic <= arr.Length - 1; ic++)
            sSrcFile[ic] = arr[ic].ToString();
        int f = 0;

        PdfReader reader = new PdfReader(sSrcFile[f]);
        int n = reader.NumberOfPages;
        Response.Write("There are " + n + " pages in the original file.");
        Document document = new Document(PageSize.A4);

        PdfWriter writer = PdfWriter.GetInstance(document, new FileStream(destinationFile, FileMode.Create));

        PdfContentByte cb = writer.DirectContent;
        PdfImportedPage page;

        int rotation;
        while (f < sSrcFile.Length)
            int i = 0;
            while (i < n)

                page = writer.GetImportedPage(reader, i);

                rotation = reader.GetPageRotation(i);
                if (rotation == 90 || rotation == 270)
                    cb.AddTemplate(page, 0, -1f, 1f, 0, 0, reader.GetPageSizeWithRotation(i).Height);
                    cb.AddTemplate(page, 1f, 0, 0, 1f, 0, 0);
                Response.Write("\n Processed page " + i);

            if (f < sSrcFile.Length)
                reader = new PdfReader(sSrcFile[f]);
                n = reader.NumberOfPages;
                Response.Write("There are " + n + " pages in the original file.");
    catch (Exception e)


Convert Word doc, docx and Excel xls, xlsx to PDF with PHP

I have found some solution after so much googling. You can also try it if tired to search for a good solution.

For common using SOAP API

You need username and password to make SOAP request on

Make registration using this and follow the steps accordingly.

Use below code in your .php file.

ini_set ('soap.wsdl_cache_enabled', 0);

// you will get this username and pass while register
define ('USERNAME', 'Username'); 
define ('PASSWORD', 'Password');

// SOAP WSDL endpoint
define ('ENDPOINT', '');
// Define timezone
$soap = new SoapClient(ENDPOINT);
        'username' => USERNAME,
        'password' => PASSWORD
$data = file_get_contents('test.doc');
        'template' => base64_encode($data),
        'format'   => 'doc'
$result = $soap->RetrieveDocument(
        'format' => 'pdf'
$data = $result->RetrieveDocumentResult;
file_put_contents('tree.pdf', base64_decode($data));

Follow this link for more information

For Ubuntu

OpenOffice and Unoconv installation Required.

from command prompt

apt-get remove --purge unoconv
git clone
cd unoconv
sudo make install

Now add below code in your PHP script and make sure file should be executable.

shell_exec('/usr/bin/unoconv -f pdf  folder/test.docx');
shell_exec('/usr/bin/unoconv -f pdf  folder/sachin.png');

Hope this solution help you.

Python: convert string from UTF-8 to Latin-1

Can you provide more details about what you are trying to do? In general, if you have a unicode string, you can use encode to convert it into string with appropriate encoding. Eg:

>>> a = u"\u00E1"
>>> type(a)
<type 'unicode'>
>>> a.encode('utf-8')
>>> a.encode('latin-1')

Python base64 data decode

(I know this is old but I wanted to post this for people like me who stumble upon it in the future) I personally just use this python code to decode base64 strings:

print open("FILE-WITH-STRING", "rb").read().decode("base64")

So you can run it in a bash script like this:

python -c 'print open("FILE-WITH-STRING", "rb").read().decode("base64")' > outputfile
file -i outputfile

twneale has also pointed out an even simpler solution: base64 -d So you can use it like this:

#Or You Can Do This
echo "STRING" | base64 -d > OUTPUTFILE

That will save the decoded string to outputfile and then attempt to identify file-type using either the file tool or you can try TrID. The following command will decode the string into a file and then use TrID to automatically identify the file's type and add the extension.

echo "STRING" | base64 -d > OUTPUTFILE; trid -ce OUTPUTFILE

Docker Networking - nginx: [emerg] host not found in upstream

Had the same problem and solved it. Please add the following line to docker-compose.yml nginx section:

  - php:waapi_php_1

Host in nginx config fastcgi_pass section should be linked inside docker-compose.yml nginx configuration.

pod has unbound PersistentVolumeClaims

You have to define a PersistentVolume providing disc space to be consumed by the PersistentVolumeClaim.

When using storageClass Kubernetes is going to enable "Dynamic Volume Provisioning" which is not working with the local file system.

To solve your issue:

  • Provide a PersistentVolume fulfilling the constraints of the claim (a size >= 100Mi)
  • Remove the storageClass-line from the PersistentVolumeClaim
  • Remove the StorageClass from your cluster

How do these pieces play together?

At creation of the deployment state-description it is usually known which kind (amount, speed, ...) of storage that application will need.
To make a deployment versatile you'd like to avoid a hard dependency on storage. Kubernetes' volume-abstraction allows you to provide and consume storage in a standardized way.

The PersistentVolumeClaim is used to provide a storage-constraint alongside the deployment of an application.

The PersistentVolume offers cluster-wide volume-instances ready to be consumed ("bound"). One PersistentVolume will be bound to one claim. But since multiple instances of that claim may be run on multiple nodes, that volume may be accessed by multiple nodes.

A PersistentVolume without StorageClass is considered to be static.

"Dynamic Volume Provisioning" alongside with a StorageClass allows the cluster to provision PersistentVolumes on demand. In order to make that work, the given storage provider must support provisioning - this allows the cluster to request the provisioning of a "new" PersistentVolume when an unsatisfied PersistentVolumeClaim pops up.

Example PersistentVolume

In order to find how to specify things you're best advised to take a look at the API for your Kubernetes version, so the following example is build from the API-Reference of K8S 1.17:

apiVersion: v1
kind: PersistentVolume
  name: ckan-pv-home
    type: local
    storage: 100Mi
    path: "/mnt/data/ckan"

The PersistentVolumeSpec allows us to define multiple attributes. I chose a hostPath volume which maps a local directory as content for the volume. The capacity allows the resource scheduler to recognize this volume as applicable in terms of resource needs.

Additional Resources:

No suitable records were found verify your bundle identifier is correct

For me, what fixed it was to enter the required details in App Store Connect -> TestFlight -> Test Information.

Once I'd done that it seemed that Xcode realised there was a new app to allow uploading to and succeeded.

(Also check your caps in your Bundle ID though. )

How do you change the document font in LaTeX?

I found the solution thanks to the link in Vincent's answer.


This changes the default font family to sans-serif.

Set selected radio from radio group with a value

When you change attribute value like mentioned above the change event is not triggered so if needed for some reasons you can trigger it like so

$('input[name=video_radio][value="' + + '"]')
       .prop('checked', true)

How can I initialize a String array with length 0 in Java?

You can use ArrayUtils.EMPTY_STRING_ARRAY from org.apache.commons.lang3

import org.apache.commons.lang3.ArrayUtils;

    class Scratch {
        public static void main(String[] args) {
            String[] strings = ArrayUtils.EMPTY_STRING_ARRAY;

WCF Service Client: The content type text/html; charset=utf-8 of the response message does not match the content type of the binding

Try browsing to http://localhost/ScraperService.svc in the web browser on the server hosting the service, using the same Windows credentials that the client normally runs under.

I imagine that IIS is displaying an html error message of some description instead of returning xml as expected.

This also can occur when you have an http proxy server that performs internet filtering. My experience with ContentKeeper is that it intercepts any http/https traffic and blocks it as "Unmanaged Content" - all we get back is an html error message. To avoid this, you can add proxy server exception rules to Internet Explorer so that the proxy doesn't intercept traffic to your site:

Control Panel > Internet Options > Connections > LAN Settings > Advanced > Proxy Settings

enter image description here

how to stop Javascript forEach?

I guess you want to use Array.prototype.find Find will break itself when it finds your specific value in the array.

var inventory = [
  {name: 'apples', quantity: 2},
  {name: 'bananas', quantity: 0},
  {name: 'cherries', quantity: 5}

function findCherries(fruit) { 
  return === 'cherries';

// { name: 'cherries', quantity: 5 }

How to set an HTTP proxy in Python 2.7?

It looks like has been updated to use the environment variables http_proxy and https_proxy.


set http_proxy=
set https_proxy=

Linux/OS X:

export http_proxy=
export https_proxy=
sudo -E python

However if this still doesn't work for you, you can always install pip through a proxy using setuptools' easy_install by setting the same environment variables.


set http_proxy=
set https_proxy=
easy_install pip

Linux/OS X:

export http_proxy=
export https_proxy=
sudo -E easy_install pip

Then once it's installed, use:

pip install --proxy="user:password@server:port" packagename

From the pip man page:

Have pip use a proxy server to access sites. This can be specified using "user:[email protected]:port" notation. If the password is left out, pip will ask for it.

SQL Server Regular expressions in T-SQL

There is some basic pattern matching available through using LIKE, where % matches any number and combination of characters, _ matches any one character, and [abc] could match a, b, or c... There is more info on the MSDN site.

TypeError: unhashable type: 'numpy.ndarray'

Your variable energies probably has the wrong shape:

>>> from numpy import array
>>> set([1,2,3]) & set(range(2, 10))
set([2, 3])
>>> set(array([1,2,3])) & set(range(2,10))
set([2, 3])
>>> set(array([[1,2,3],])) & set(range(2,10))
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: unhashable type: 'numpy.ndarray'

And that's what happens if you read columnar data using your approach:

>>> data
array([[  1.,   2.,   3.],
       [  3.,   4.,   5.],
       [  5.,   6.,   7.],
       [  8.,   9.,  10.]])
>>> hsplit(data,3)[0]
array([[ 1.],
       [ 3.],
       [ 5.],
       [ 8.]])

Probably you can simply use

>>> data[:,0]
array([ 1.,  3.,  5.,  8.])


(P.S. Your code looks like it's undecided about whether it's data or elementdata. I've assumed it's simply a typo.)

Inserting into Oracle and retrieving the generated sequence ID

Expanding a bit on the answers from @Guru and @Ronnis, you can hide the sequence and make it look more like an auto-increment using a trigger, and have a procedure that does the insert for you and returns the generated ID as an out parameter.

create table batch(batchid number,
    batchname varchar2(30),
    batchtype char(1),
    source char(1),
    intarea number)

create sequence batch_seq start with 1

create trigger batch_bi
before insert on batch
for each row
    select batch_seq.nextval into :new.batchid from dual;

create procedure insert_batch(v_batchname batch.batchname%TYPE,
    v_batchtype batch.batchtype%TYPE,
    v_source batch.source%TYPE,
    v_intarea batch.intarea%TYPE,
    v_batchid out batch.batchid%TYPE)
    insert into batch(batchname, batchtype, source, intarea)
    values(v_batchname, v_batchtype, v_source, v_intarea)
    returning batchid into v_batchid;

You can then call the procedure instead of doing a plain insert, e.g. from an anoymous block:

    l_batchid batch.batchid%TYPE;
    insert_batch(v_batchname => 'Batch 1',
        v_batchtype => 'A',
        v_source => 'Z',
        v_intarea => 1,
        v_batchid => l_batchid);
    dbms_output.put_line('Generated id: ' || l_batchid);

    insert_batch(v_batchname => 'Batch 99',
        v_batchtype => 'B',
        v_source => 'Y',
        v_intarea => 9,
        v_batchid => l_batchid);
    dbms_output.put_line('Generated id: ' || l_batchid);

Generated id: 1
Generated id: 2

You can make the call without an explicit anonymous block, e.g. from SQL*Plus:

variable l_batchid number;
exec insert_batch('Batch 21', 'C', 'X', 7, :l_batchid);

... and use the bind variable :l_batchid to refer to the generated value afterwards:

print l_batchid;
insert into some_table values(:l_batch_id, ...);

convert base64 to image in javascript/jquery

You can just create an Image object and put the base64 as its src, including the data:image... part like this:

var image = new Image();
image.src = 'data:image/png;base64,iVBORw0K...';

It's what they call "Data URIs" and here's the compatibility table for inner peace.

How to remove .html from URL?

This should work for you: will display the contents of
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}.html -f
RewriteRule ^(.+)$ $1.html [L,QSA]

#301 from to
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /.*\.html\ HTTP/
RewriteRule ^(.*)\.html$ /$1 [R=301,L]

Recursion in Python? RuntimeError: maximum recursion depth exceeded while calling a Python object

Python lacks the tail recursion optimizations common in functional languages like lisp. In Python, recursion is limited to 999 calls (see sys.getrecursionlimit).

If 999 depth is more than you are expecting, check if the implementation lacks a condition that stops recursion, or if this test may be wrong for some cases.

I dare to say that in Python, pure recursive algorithm implementations are not correct/safe. A fib() implementation limited to 999 is not really correct. It is always possible to convert recursive into iterative, and doing so is trivial.

It is not reached often because in many recursive algorithms the depth tend to be logarithmic. If it is not the case with your algorithm and you expect recursion deeper than 999 calls you have two options:

1) You can change the recursion limit with sys.setrecursionlimit(n) until the maximum allowed for your platform:


Set the maximum depth of the Python interpreter stack to limit. This limit prevents infinite recursion from causing an overflow of the C stack and crashing Python.

The highest possible limit is platform-dependent. A user may need to set the limit higher when she has a program that requires deep recursion and a platform that supports a higher limit. This should be done with care, because a too-high limit can lead to a crash.

2) You can try to convert the algorithm from recursive to iterative. If recursion depth is bigger than allowed by your platform, it is the only way to fix the problem. There are step by step instructions on the Internet and it should be a straightforward operation for someone with some CS education. If you are having trouble with that, post a new question so we can help.

How to check if a json key exists?

you could JSONObject#has, providing the key as input and check if the method returns true or false. You could also

use optString instead of getString:

Returns the value mapped by name if it exists, coercing it if necessary. Returns the empty string if no such mapping exists

IndentationError: unindent does not match any outer indentation level

To easily check for problems with tabs/spaces you can actually do this:

python -m tabnanny

or you can just set up your editor correctly of course :-)

How to include js and CSS in JSP with spring MVC

Put your style.css directly into the webapp/css folder, not into the WEB-INF folder.

Then add the following code into your spring-dispatcher-servlet.xml

<mvc:resources mapping="/css/**" location="/css/" />

and then add following code into your jsp page

<link rel="stylesheet" type="text/css" href="css/style.css"/>

I hope it will work.

ISO time (ISO 8601) in Python

You'll need to use os.stat to get the file creation time and a combination of time.strftime and time.timezone for formatting:

>>> import time
>>> import os
>>> t = os.stat('C:/Path/To/File.txt').st_ctime
>>> t = time.localtime(t)
>>> formatted = time.strftime('%Y-%m-%d %H:%M:%S', t)
>>> tz = str.format('{0:+06.2f}', float(time.timezone) / 3600)
>>> final = formatted + tz
>>> final
'2008-11-24 14:46:08-02.00'

What is the best algorithm for overriding GetHashCode?

Here's my helper class using Jon Skeet's implementation.

public static class HashCode
    public const int Start = 17;

    public static int Hash<T>(this int hash, T obj)
        var h = EqualityComparer<T>.Default.GetHashCode(obj);
        return unchecked((hash * 31) + h);


public override int GetHashCode()
    return HashCode.Start

If you want to avoid writing an extension method for System.Int32:

public readonly struct HashCode
    private readonly int _value;

    public HashCode(int value) => _value = value;

    public static HashCode Start { get; } = new HashCode(17);

    public static implicit operator int(HashCode hash) => hash._value;

    public HashCode Hash<T>(T obj)
        var h = EqualityComparer<T>.Default.GetHashCode(obj);
        return unchecked(new HashCode((_value * 31) + h));

    public override int GetHashCode() => _value;

It still avoids any heap allocation and is used exactly the same way:

public override int GetHashCode()
    // This time `HashCode.Start` is not an `Int32`, it's a `HashCode` instance.
    // And the result is implicitly converted to `Int32`.
    return HashCode.Start

Edit (May 2018): EqualityComparer<T>.Default getter is now a JIT intrinsic - the pull request is mentioned by Stephen Toub in this blog post.

Get the current cell in Excel VB

Try this

Dim app As Excel.Application = Nothing
Dim Active_Cell As Excel.Range = Nothing

            app = CType(Marshal.GetActiveObject("Excel.Application"), Excel.Application)
 Active_Cell = app.ActiveCell

Catch ex As Exception
            Exit Sub
        End Try

'             .address will return the cell reference :)

How do I setup a SSL certificate for an express.js server?

This is my working code for express 4.0.

express 4.0 is very different from 3.0 and others.

4.0 you have /bin/www file, which you are going to add https here.

"npm start" is standard way you start express 4.0 server.

readFileSync() function should use __dirname get current directory

while require() use ./ refer to current directory.

First you put private.key and public.cert file under /bin folder, It is same folder as WWW file.

no such directory found error:

  key: fs.readFileSync('../private.key'),

  cert: fs.readFileSync('../public.cert')

error, no such directory found

  key: fs.readFileSync('./private.key'),

  cert: fs.readFileSync('./public.cert')

Working code should be

key: fs.readFileSync(__dirname + '/private.key', 'utf8'),

cert: fs.readFileSync(__dirname + '/public.cert', 'utf8')

Complete https code is:

const https = require('https');
const fs = require('fs');

// readFileSync function must use __dirname get current directory
// require use ./ refer to current directory.

const options = {
   key: fs.readFileSync(__dirname + '/private.key', 'utf8'),
  cert: fs.readFileSync(__dirname + '/public.cert', 'utf8')

 // Create HTTPs server.

 var server = https.createServer(options, app);

Java: how do I get a class literal from a generic type?

You could use a helper method to get rid of @SuppressWarnings("unchecked") all over a class.

private static <T> Class<T> generify(Class<?> cls) {
    return (Class<T>)cls;

Then you could write

Class<List<Foo>> cls = generify(List.class);

Other usage examples are

  Class<Map<String, Integer>> cls;

  cls = generify(Map.class);

  cls = TheClass.<Map<String, Integer>>generify(Map.class);


public void funWithTypeParam(Class<Map<String, Integer>> cls) {

However, since it is rarely really useful, and the usage of the method defeats the compiler's type checking, I would not recommend to implement it in a place where it is publicly accessible.

right align an image using CSS HTML

There are a few different ways to do this but following is a quick sample of one way.

<img src="yourimage.jpg" style="float:right" /><div style="clear:both">Your text here.</div>

I used inline styles for this sample but you can easily place these in a stylesheet and reference the class or id.

Hive insert query like SQL

You can't do insert into to insert single record. It's not supported by Hive. You may place all new records that you want to insert in a file and load that file into a temp table in Hive. Then using insert command insert those rows into a new partition of your main Hive table. The constraint here is your main table will have to be pre partitioned. If you don't use partition then your whole table will be replaced with these new records.

How can I read the contents of an URL with Python?

You can use requests and beautifulsoup libraries to read data on a website. Just install these two libraries and type the following code.

import requests
import bs4

You will get all the information you need about the library.

How to define dimens.xml for every different screen size in android?

Use Scalable DP

Although making a different layout for different screen sizes is theoretically a good idea, it can get very difficult to accommodate for all screen dimensions, and pixel densities. Having over 20+ different dimens.xml files as suggested in the above answers, is not easy to manage at all.

How To Use:

To use sdp:

  1. Include implementation '' in your build.gradle,
  2. Replace any dp value such as 50dp with a @dimen/50_sdp like so:

     android:text="Hello World!" />

How It Works:

sdp scales with the screen size because it is essentially a huge list of different dimens.xml for every possible dp value.

enter image description here

See It In Action:

Here it is on three devices with widely differing screen dimensions, and densities:

enter image description here

Note that the sdp size unit calculation includes some approximation due to some performance and usability constraints.

NUnit vs. MbUnit vs. MSTest vs.

It's not a big deal on a small/personal scale, but it can become a bigger deal quickly on a larger scale. My employer is a large Microsoft shop, but won't/can't buy into Team System/TFS for a number of reasons. We currently use Subversion + Orcas + MBUnit + TestDriven.NET and it works well, but getting TD.NET was a huge hassle. The version sensitivity of MBUnit + TestDriven.NET is also a big hassle, and having one additional commercial thing (TD.NET) for legal to review and procurement to handle and manage, isn't trivial. My company, like a lot of companies, are fat and happy with a MSDN Subscription model, and it's just not used to handling one off procurements for hundreds of developers. In other words, the fully integrated MS offer, while definitely not always best-of-bread, is a significant value-add in my opinion.

I think we'll stay with our current step because it works and we've already gotten over the hump organizationally, but I sure do wish MS had a compelling offering in this space so we could consolidate and simplify our dev stack a bit.

Linker Error C++ "undefined reference "

Your header file Hash.h declares "what class hash should look like", but not its implementation, which is (presumably) in some other source file we'll call Hash.cpp. By including the header in your main file, the compiler is informed of the description of class Hash when compiling the file, but not how class Hash actually works. When the linker tries to create the entire program, it then complains that the implementation (toHash::insert(int, char)) cannot be found.

The solution is to link all the files together when creating the actual program binary. When using the g++ frontend, you can do this by specifying all the source files together on the command line. For example:

g++ -o main Hash.cpp main.cpp

will create the main program called "main".

How to stop event propagation with inline onclick attribute?

According to this page, in IE you need:

event.cancelBubble = true

Sorting a set of values

From a comment:

I want to sort each set.

That's easy. For any set s (or anything else iterable), sorted(s) returns a list of the elements of s in sorted order:

>>> s = set(['0.000000000', '0.009518000', '10.277200999', '0.030810999', '0.018384000', '4.918560000'])
>>> sorted(s)
['0.000000000', '0.009518000', '0.018384000', '0.030810999', '10.277200999', '4.918560000']

Note that sorted is giving you a list, not a set. That's because the whole point of a set, both in mathematics and in almost every programming language,* is that it's not ordered: the sets {1, 2} and {2, 1} are the same set.

You probably don't really want to sort those elements as strings, but as numbers (so 4.918560000 will come before 10.277200999 rather than after).

The best solution is most likely to store the numbers as numbers rather than strings in the first place. But if not, you just need to use a key function:

>>> sorted(s, key=float)
['0.000000000', '0.009518000', '0.018384000', '0.030810999', '4.918560000', '10.277200999']

For more information, see the Sorting HOWTO in the official docs.

* See the comments for exceptions.

App.Config change value

AppSettings.Set does not persist the changes to your configuration file. It just changes it in memory. If you put a breakpoint on System.Configuration.ConfigurationManager.AppSettings.Set("lang", lang);, and add a watch for System.Configuration.ConfigurationManager.AppSettings[0] you will see it change from "English" to "Russian" when that line of code runs.

The following code (used in a console application) will persist the change.

class Program
    static void Main(string[] args)
        UpdateSetting("lang", "Russian");

    private static void UpdateSetting(string key, string value)
        Configuration configuration = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
        configuration.AppSettings.Settings[key].Value = value;


From this post:

One major point to note with the above is that if you are running this from the debugger (within Visual Studio) then the app.config file will be overwritten each time you build. The best way to test this is to build your application and then navigate to the output directory and launch your executable from there. Within the output directory you will also find a file named YourApplicationName.exe.config which is your configuration file. Open this in Notepad to see that the changes have in fact been saved.

How do I create a Java string from the contents of a file?

Java attempts to be extremely general and flexible in all it does. As a result, something which is relatively simple in a scripting language (your code would be replaced with "open(file).read()" in python) is a lot more complicated. There doesn't seem to be any shorter way of doing it, except using an external library (like Willi aus Rohr mentioned). Your options:

  • Use an external library.
  • Copy this code into all your projects.
  • Create your own mini-library which contains functions you use often.

Your best bet is probably the 2nd one, as it has the least dependencies.

Redirect website after certain amount of time

Place the following HTML redirect code between the and tags of your HTML code.

<meta HTTP-EQUIV="REFRESH" content="3; url=">

The above HTML redirect code will redirect your visitors to another web page instantly. The content="3; may be changed to the number of seconds you want the browser to wait before redirecting. 4, 5, 8, 10 or 15 seconds, etc.

How can I alter a primary key constraint using SQL syntax?

Yes. The only way would be to drop the constraint with an Alter table then recreate it.

ALTER TABLE <Table_Name>
DROP CONSTRAINT <constraint_name>

ALTER TABLE <Table_Name>
ADD CONSTRAINT <constraint_name> PRIMARY KEY (<Column1>,<Column2>)

Bootstrap number validation

you can use PATTERN:

<input class="form-control" minlength="1" pattern="[0-9]*" [(ngModel)]="value" #name="ngModel">

<div *ngIf="name.invalid && (name.dirty || name.touched)" class="text-danger">
  <div *ngIf="name.errors?.pattern">Is not a number</div>

Why can't static methods be abstract in Java?

because if you are using any static member or static variable in class it will load at class loading time.

How can I view the contents of an ElasticSearch index?

I can recommend Elasticvue, which is modern, free and open source. It allows accessing your ES instance via browser add-ons quite easily (supports Firefox, Chrome, Edge). But there are also further ways.

Just make sure you set cors values in elasticsearch.yml appropiate.

How to change default JRE for all Eclipse workspaces?

I ran into a similar issue where eclipse was not using my current %JAVA_HOME% that was on the path and was instead using an older version. The documentation points out that if no -vm is specified in the ini file, eclipse will search for a shared library jvm.dll This appears in the registry under the key HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\JavaSoft\Java Runtime Environment that gets installed when using the windows java installer (key might be a bit different based on 64-bit vs 32-bit, but search for jvm.dll). Because it was finding this shared library on my path before the %JAVA_HOME%/bin, it was using the old version.

Like others have stated, the easiest way to deal with this is to specify the specific vm you want to use in the eclipse.ini file. I'm writing this because I couldn't figure out how it was still using the old version when it wasn't specified anywhere on the path or eclipse.ini file.

See link to doc below:

Finding a VM and using the JNI Invocation API

The Eclipse launcher is capable of loading the Java VM in the eclipse process using the Java Native Interface Invocation API. The launcher is still capable of starting the Java VM in a separate process the same as previous version of Eclipse did. Which method is used depends on how the VM was found.

No -vm specified

When no -vm is specified, the launcher looks for a virtual machine first in a jre directory in the root of eclipse and then on the search path. If java is found in either location, then the launcher looks for a jvm shared library (jvm.dll on Windows, on *nix platforms) relative to that java executable.

  • If a jvm shared library is found the launcher loads it and uses the JNI invocation API to start the vm.
  • If no jvm shared library is found, the launcher executes the java launcher to start the vm in a new process.

-vm specified on the command line or in eclipse.ini

Eclipse can be started with "-vm " to indicate a virtual machine to use. There are several possibilities for the value of :

  • directory: is a directory. We look in that directory for:
    • (1) a java launcher or
    • (2) the jvm shared library.

If we find the jvm shared library, we use JNI invocation. If we find a launcher, we attempt to find a jvm library in known locations relative to the launcher. If we find one, we use JNI invocation. If no jvm library is found, we exec java in a new process.

  • java.exe/javaw.exe: is a path to a java launcher. We exec that java launcher to start the vm in a new process.

  • jvm dll or so: is a path to a jvm shared library. We attempt to load that library and use the JNI Invocation API to start the vm in the current process.

Bulk create model objects in django

as of the django development, there exists bulk_create as an object manager method which takes as input an array of objects created using the class constructor. check out django docs

Detach (move) subdirectory into separate Git repository

You can easily try the

This worked for me. The issues i faced in the steps given above are

  1. in this command git filter-branch --prune-empty --subdirectory-filter FOLDER-NAME BRANCH-NAME The BRANCH-NAME is master

  2. if the last step fails when committing due to protection issue follow -

Difference in Months between two dates in JavaScript

below logic will fetch difference in months


Evaluating a mathematical expression in a string

I think I would use eval(), but would first check to make sure the string is a valid mathematical expression, as opposed to something malicious. You could use a regex for the validation.

eval() also takes additional arguments which you can use to restrict the namespace it operates in for greater security.

Microsoft Advertising SDK doesn't deliverer ads

I only use MicrosoftAdvertising.Mobile and Microsoft.Advertising.Mobile.UI and I am served ads. The SDK should only add the DLLs not reference itself.

Note: You need to explicitly set width and height Make sure the phone dialer, and web browser capabilities are enabled

Followup note: Make sure that after you've removed the SDK DLL, that the xmlns references are not still pointing to it. The best route to take here is

  1. Remove the XAML for the ad
  2. Remove the xmlns declaration (usually at the top of the page, but sometimes will be declared in the ad itself)
  3. Remove the bad DLL (the one ending in .SDK )
  4. Do a Clean and then Build (clean out anything remaining from the DLL)
  5. Add the xmlns reference (actual reference is below)
  6. Add the ad to the page (example below)

Here is the xmlns reference:


Then the ad itself:

<AdNamespace:AdControl x:Name="myAd" Height="80" Width="480"                    AdUnitId="yourAdUnitIdHere" ApplicationId="yourIdHere"/> 

How to sort a NSArray alphabetically?

The simplest approach is, to provide a sort selector (Apple's documentation for details)


sortedArray = [anArray sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];


let descriptor: NSSortDescriptor = NSSortDescriptor(key: "YourKey", ascending: true, selector: "localizedCaseInsensitiveCompare:")
let sortedResults: NSArray = temparray.sortedArrayUsingDescriptors([descriptor])

Apple provides several selectors for alphabetic sorting:

  • compare:
  • caseInsensitiveCompare:
  • localizedCompare:
  • localizedCaseInsensitiveCompare:
  • localizedStandardCompare:


var students = ["Kofi", "Abena", "Peter", "Kweku", "Akosua"]
// Prints "["Abena", "Akosua", "Kofi", "Kweku", "Peter"]"


How do I revert all local changes in Git managed project to previous state?

simply execute -

git stash

it will remove all your local changes. and you can also use it later by executing -

git stash apply 

vba listbox multicolumn add

Simplified example (with counter):

With Me.lstbox
    .ColumnCount = 2
    .ColumnWidths = "60;60"
    .List(i, 0) = Company_ID
    .List(i, 1) = Company_name 
    i = i + 1

end with

Make sure to start the counter with 0, not 1 to fill up a listbox.

Python String and Integer concatenation

for i in range(11):
    string = "string{0}".format(i)

What you did (range[1,10]) is

  • a TypeError since brackets denote an index (a[3]) or a slice (a[3:5]) of a list,
  • a SyntaxError since [1,10] is invalid, and
  • a double off-by-one error since range(1,10) is [1, 2, 3, 4, 5, 6, 7, 8, 9], and you seem to want [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

And string = "string" + i is a TypeError since you can't add an integer to a string (unlike JavaScript).

Look at the documentation for Python's new string formatting method, it is very powerful.

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

I typically perform the validation on the client side:

<asp:checkbox id="chkTerms" text=" I agree to the terms" ValidationGroup="vg" runat="Server"  />
<asp:CustomValidator id="vTerms"
                ErrorMessage="<br/>Terms and Conditions are required." 

<asp:Button ID="btnSubmit" OnClick="btnSubmit_Click" CausesValidation="true" Text="Submit" ValidationGroup="vg" runat="server" />

    function validateTerms(source, arguments) {
        var $c = $('#<%= chkTerms.ClientID %>');
            arguments.IsValid = true;
        } else {
            arguments.IsValid = false;

Creating a list of objects in Python

If I understand correctly your question, you ask a way to execute a deep copy of an object. What about using copy.deepcopy?

import copy

x = SimpleClass()

for count in range(0,4):
  y = copy.deepcopy(x)
  y.attr1= '*Bob* '* count

A deepcopy is a recursive copy of the entire object. For more reference, you can have a look at the python documentation:

Set environment variables from file of key/value pairs

The shortest way I found:

Your .env file:


Then just

. ./.env && echo ${VARIABLE_NAME}

Bonus: Because it's a short one-liner, it's very useful in package.json file

  "scripts": {
    "echo:variable": ". ./.env && echo ${VARIABLE_NAME}"

How to give credentials in a batch script that copies files to a network location?

You can also map the share to a local drive as follows:

net use X: "\\servername\share" /user:morgan password

macro run-time error '9': subscript out of range

When you get the error message, you have the option to click on "Debug": this will lead you to the line where the error occurred. The Dark Canuck seems to be right, and I guess the error occurs on the line:

Sheets("Sheet1").protect Password:="btfd"

because most probably the "Sheet1" does not exist. However, if you say "It works fine, but when I save the file I get the message: run-time error '9': subscription out of range" it makes me think the error occurs on the second line:


Could you please check this by pressing the Debug button first? And most important, as Gordon Bell says, why are you using a macro to protect a workbook?

How get an apostrophe in a string in javascript

You can try the following:

theAnchorText = "I'm home";


theAnchorText = 'I\'m home';

Python3: ImportError: No module named '_ctypes' when using Value from module multiprocessing

If you use pyenv and get error "No module named '_ctypes'" (like i am) on Debian/Raspbian/Ubuntu you need to run this commands:

sudo apt-get install libffi-dev
pyenv uninstall 3.7.6
pyenv install 3.7.6

Put your version of python instead of 3.7.6

get all characters to right of last dash

I can see this post was viewed over 46,000 times. I would bet many of the 46,000 viewers are asking this question simply because they just want the file name... and these answers can be a rabbit hole if you cannot make your substring verbatim using the at sign.

If you simply want to get the file name, then there is a simple answer which should be mentioned here. Even if it's not the precise answer to the question.

result = Path.GetFileName(fileName);


Referenced Project gets "lost" at Compile Time

Make sure that both projects have same target framework version here: right click on project -> properties -> application (tab) -> target framework

Also, make sure that the project "logger" (which you want to include in the main project) has the output type "Class Library" in: right click on project -> properties -> application (tab) -> output type

Finally, Rebuild the solution.

How to turn off Wifi via ADB?

use with quotes

ex: adb shell "svc wifi enable"

this will work :)

Get controller and action name from within controller?

Try this code

add this override method to controller

protected override void OnActionExecuting(ActionExecutingContext actionExecutingContext)
   var actionName = actionExecutingContext.ActionDescriptor.ActionName;
   var controllerName = actionExecutingContext.ActionDescriptor.ControllerDescriptor.ControllerName;

How to catch curl errors in PHP

If CURLOPT_FAILONERROR is false, http errors will not trigger curl errors.

if (@$_GET['curl']=="yes") {
  header('HTTP/1.1 503 Service Temporarily Unavailable');
} else {
  $ch=curl_init($url = "http://".$_SERVER['SERVER_NAME'].$_SERVER['PHP_SELF']."?curl=yes");
  curl_setopt($ch, CURLOPT_FAILONERROR, true);
  $http_status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
  $curl_errno= curl_errno($ch);
  if ($http_status==503)
    echo "HTTP Status == 503 <br/>";
  echo "Curl Errno returned $curl_errno <br/>";

function declaration isn't a prototype


extern int testlib(void);

Official reasons for "Software caused connection abort: socket write error"

The is thrown when there is an error creating or accessing a socket (such as TCP). This usually can be caused when the server has terminated the connection (without properly closing it), so before getting the full response. In most cases this can be caused either by the timeout issue (e.g. the response takes too much time or server is overloaded with the requests), or the client sent the SYN, but it didn't receive ACK (acknowledgment of the connection termination). For timeout issues, you can consider increasing the timeout value.

The Socket Exception usually comes with the specified detail message about the issue.

Example of detailed messages:

  • Software caused connection abort: recv failed.

    The error indicates an attempt to send the message and the connection has been aborted by your server. If this happened while connecting to the database, this can be related to using not compatible Connector/J JDBC driver.

    Possible solution: Make sure you've proper libraries/drivers in your CLASSPATH.

  • Software caused connection abort: connect.

    This can happen when there is a problem to connect to the remote. For example due to virus-checker rejecting the remote mail requests.

    Possible solution: Check Virus scan service whether it's blocking the port for the outgoing requests for connections.

  • Software caused connection abort: socket write error.

    Possible solution: Make sure you're writing the correct length of bytes to the stream. So double check what you're sending. See this thread.

  • Connection reset by peer: socket write error / Connection aborted by peer: socket write error

    The application did not check whether keep-alive connection had been timed out on the server side.

    Possible solution: Ensure that the HttpClient is non-null before reading from the connection.E13222_01

  • Connection reset by peer.

    The connection has been terminated by the peer (server).

  • Connection reset.

    The connection has been either terminated by the client or closed by the server end of the connection due to request with the request.

    See: What's causing my Connection reset?

How to spawn a process and capture its STDOUT in .NET?

Here's some full and simple code to do this. This worked fine when I used it.

var processStartInfo = new ProcessStartInfo
    FileName = @"C:\SomeProgram",
    Arguments = "Arguments",
    RedirectStandardOutput = true,
    UseShellExecute = false
var process = Process.Start(processStartInfo);
var output = process.StandardOutput.ReadToEnd();

Note that this only captures standard output; it doesn't capture standard error. If you want both, use this technique for each stream.

Should a RESTful 'PUT' operation return something

seems ok... though I'd think a rudimentary indication of success/failure/time posted/# bytes received/etc. would be preferable.

edit: I was thinking along the lines of data integrity and/or record-keeping; metadata such as an MD5 hash or timestamp for time received may be helpful for large datafiles.

How to get the current user's Active Directory details in C#

Alan already gave you the right answer - use the sAMAccountName to filter your user.

I would add a recommendation on your use of DirectorySearcher - if you only want one or two pieces of information, add them into the "PropertiesToLoad" collection of the DirectorySearcher.

Instead of retrieving the whole big user object and then picking out one or two items, this will just return exactly those bits you need.


adSearch.PropertiesToLoad.Add("sn");  // surname = last name
adSearch.PropertiesToLoad.Add("givenName");  // given (or first) name
adSearch.PropertiesToLoad.Add("mail");  // e-mail addresse
adSearch.PropertiesToLoad.Add("telephoneNumber");  // phone number

Those are just the usual AD/LDAP property names you need to specify.

jQuery or JavaScript auto click

You haven't provided your javascript code, but the usual cause of this type of issue is not waiting till the page is loaded. Remember that most javascript is executed before the DOM is loaded, so code trying to manipulate it won't work.

To run code after the page has finished loading, use the $(document).ready callback:


scp files from local to remote machine error: no such file or directory

As @Astariul said, path to the file might cause this bug.
In addition, any parent directory which contains non-ASCII character, for example Chinese, will cause this.
In that case, you should rename you parent directory

Laravel: Auth::user()->id trying to get a property of a non-object

In Laravel 5.6 I use

use Auth;
$user_id = Auth::user()->id;

as the other suggestion


seems to apply to older versions of Laravel 5.x and didn't work for me.

How to fix Error: "Could not find schema information for the attribute/element" by creating schema

In my case I had an ambiguous reference in my code. I restarted Visual Studio and was able to see the error message. When I resolved this the other error disappeared.

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


 pause ()
 while [ "$REPLY" == "Y" ] || [ "$REPLY" != "y" ]
  echo -e "\t\tPress 'y' to continue\t\t\tPress 'n' to quit"
  read -n1 -s
      case "$REPLY" in
      "n")  exit                      ;;
      "N")  echo "case sensitive!!"   ;; 
      "y")  clear                     ;;
      "Y")  echo "case sensitive!!"   ;;
      * )  echo "$REPLY is Invalid Option"     ;;
 echo "Hi"

How to remove certain characters from a string in C++?

If you have access to a compiler that supports variadic templates, you can use this:

#include <iostream>
#include <string>
#include <algorithm>

template<char ... CharacterList>
inline bool check_characters(char c) {
    char match_characters[sizeof...(CharacterList)] = { CharacterList... };
    for(int i = 0; i < sizeof...(CharacterList); ++i) {
        if(c == match_characters[i]) {
            return true;
    return false;

template<char ... CharacterList>
inline void strip_characters(std::string & str) {
    str.erase(std::remove_if(str.begin(), str.end(), &check_characters<CharacterList...>), str.end());

int main()
    std::string str("(555) 555-5555");
    strip_characters< '(',')','-' >(str);
    std::cout << str << std::endl;

Cmake is not able to find Python-libraries

For me was helpful next:

> apt-get install python-dev python3-dev

Django set field value after a form is initialized

If you've already initialized the form, you can use the initial property of the field. For example,

form = CustomForm()
form.fields["Email"].initial = GetEmailString()

AngularJS routing without the hash '#'


It is recommended to use the HTML 5 style (PathLocationStrategy) as location strategy in Angular

** Because

  1. It produces the clean and SEO Friendly URLs that are easier for users to understand and remember.
  2. You can take advantage of the server-side rendering, which will make our application load faster, by rendering the pages in the server first before delivering it the client.

Use Hashlocationstrtegy only if you have to support the older browsers.

Click here to know more

Set NOW() as Default Value for datetime datatype?

The best way is using "DEFAULT 0". Other way:

    /************ ROLE ************/
    drop table if exists `role`;
    create table `role` (
        `id_role` bigint(20) unsigned not null auto_increment,
        `date_created` datetime,
        `date_deleted` datetime,
        `name` varchar(35) not null,
        `description` text,
        primary key (`id_role`)
    ) comment='';

    drop trigger if exists `role_date_created`;
    create trigger `role_date_created` before insert
        on `role`
        for each row 
        set new.`date_created` = now();

Entity Framework. Delete all rows in table

In my code I didn't really have nice access to the Database object, so you can do it on the DbSet where you also is allowed to use any kind of sql. It will sort of end out like this:

var p = await _db.Persons.FromSql("truncate table Persons;select top 0 * from Persons").ToListAsync();

Custom Cell Row Height setting in storyboard is not responding

You can get height of UITableviewCell (in UITableviewController - static cells) from storyboard with help of following lines.

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
   CGFloat height = [super tableView:tableView heightForRowAtIndexPath:indexPath];

    return height;

Java URL encoding of query string parameters

In my case i just needed to pass the whole url and encode only the value of each parameters. I didn't find a common code to do that so (!!) so i created this small method to do the job :

public static String encodeUrl(String url) throws Exception {
    if (url == null || !url.contains("?")) {
        return url;

    List<String> list = new ArrayList<>();
    String rootUrl = url.split("\\?")[0] + "?";
    String paramsUrl = url.replace(rootUrl, "");
    List<String> paramsUrlList = Arrays.asList(paramsUrl.split("&"));
    for (String param : paramsUrlList) {
        if (param.contains("=")) {
            String key = param.split("=")[0];
            String value = param.replace(key + "=", "");
            list.add(key + "=" +  URLEncoder.encode(value, "UTF-8"));
        else {

    return rootUrl + StringUtils.join(list, "&");

public static String decodeUrl(String url) throws Exception {
    return URLDecoder.decode(url, "UTF-8");

It uses org.apache.commons.lang3.StringUtils

What are ODEX files in Android?


According to the docs: an .odex file:

contains AOT compiled code for methods in the APK.

Furthermore, they appear to be regular shared libraries, since if you get any app, and check:

file /data/app/*/oat/arm64/base.odex

it says:

base.odex: ELF shared object, 64-bit LSB arm64, stripped

and aarch64-linux-gnu-objdump -d base.odex seems to work and give some meaningful disassembly (but also some rubbish sections).

Maven dependency update on commandline

mvn -Dschemaname=public liquibase:update

Get Hard disk serial Number

In case you want to use it for copy protection and you need it to return always the same serial on one computer (of course as far as first hdd or ssd is not changed) I would recommend code below. For ManagementClass you need to add reference to System.Management. P.S. Without "InterfaceType" and "DeviceID" check that method can return serial of random disk or serial of USB flash drive which connected to pc right now.

    public static string GetSerial()
            var mc = new ManagementClass("Win32_DiskDrive");
            var moc = mc.GetInstances();
            var res = string.Empty;
            var resList = new List<string>(moc.Count);

            foreach (ManagementObject mo in moc)
                    if (mo["InterfaceType"].ToString().Replace(" ", string.Empty) == "USB")

                    res = mo["SerialNumber"].ToString().Replace(" ", string.Empty);
                    if (mo["DeviceID"].ToString().Replace(" ", string.Empty).Contains("0"))
                        if (!string.IsNullOrWhiteSpace(res))
                            return res;

            res = resList[0];
            if (!string.IsNullOrWhiteSpace(res))
                return res;

        return string.Empty;

What is the use of <<<EOD in PHP?

there are four types of strings available in php. They are single quotes ('), double quotes (") and Nowdoc (<<<'EOD') and heredoc(<<<EOD) strings

you can use both single quotes and double quotes inside heredoc string. Variables will be expanded just as double quotes.

nowdoc strings will not expand variables just like single quotes.


How do I use a file grep comparison inside a bash if/else statement?

if takes a command and checks its return value. [ is just a command.

if grep -q ...

How merge two objects array in angularjs?

You can use angular.extend(dest, src1, src2,...);

In your case it would be :

angular.extend($, data);

See documentation here :

Otherwise, if you only get new values from the server, you can do the following

for (var i=0; i<data.length; i++){

.NET Out Of Memory Exception - Used 1.3GB but have 16GB installed

As already mentioned, compiling the app in x64 gives you far more available memory.

But in the case one must build an app in x86, there is a way to raise the memory limit from 1,2GB to 4GB (which is the actual limit for 32 bit processes):

In the VC/bin folder of the Visual Studio installation directory, there must be an editbin.exe file. So in my default installation I find it under

C:\Program Files (x86)\Microsoft Visual Studio 10.0\VC\bin\editbin.exe

In order to make the program work, maybe you must execute vcvars32.bat in the same directory first. Then a

editbin /LARGEADDRESSAWARE <your compiled exe file>

is enough to let your program use 4GB RAM. <your compiled exe file> is the exe, which VS generated while compiling your project.

If you want to automate this behavior every time you compile your project, use the following Post-Build event for the executed project:

if exist "$(DevEnvDir)..\tools\vsvars32.bat" (
   call "$(DevEnvDir)..\tools\vsvars32.bat"
   editbin /largeaddressaware "$(TargetPath)"

Sidenote: The same can be done with the devenv.exe to let Visual Studio also use 4GB RAM instead of 1.2GB (but first backup the old devenv.exe).

How to add element in List while iterating in java?

You can't use a foreach statement for that. The foreach is using internally an iterator:

The iterators returned by this class's iterator and listIterator methods are fail-fast: if the list is structurally modified at any time after the iterator is created, in any way except through the iterator's own remove or add methods, the iterator will throw a ConcurrentModificationException.

(From ArrayList javadoc)

In the foreach statement you don't have access to the iterator's add method and in any case that's still not the type of add that you want because it does not append at the end. You'll need to traverse the list manually:

int listSize = list.size();
for(int i = 0; i < listSize; ++i)

Note that this is only efficient for Lists that allow random access. You can check for this feature by checking whether the list implements the RandomAccess marker interface. An ArrayList has random access. A linked list does not.

Eclipse Error: "Failed to connect to remote VM"

I am using jboss so solution to your problem was restart.

service jboss-portal restart

How to execute .sql script file using JDBC

I use this bit of code to import sql statements created by mysqldump:

public static void importSQL(Connection conn, InputStream in) throws SQLException
    Scanner s = new Scanner(in);
    Statement st = null;
        st = conn.createStatement();
        while (s.hasNext())
            String line =;
            if (line.startsWith("/*!") && line.endsWith("*/"))
                int i = line.indexOf(' ');
                line = line.substring(i + 1, line.length() - " */".length());

            if (line.trim().length() > 0)
        if (st != null) st.close();

How to find the mysql data directory from command line in windows

Check if the Data directory is in "C:\ProgramData\MySQL\MySQL Server 5.7\Data". This is where it is on my computer. Someone might find this helpful.

Create a button programmatically and set a background image

Your code should look like below

let image = UIImage(named: "name") as UIImage?
let button   = UIButton(type: UIButtonType.Custom) as UIButton
button.frame = CGRectMake(100, 100, 100, 100)
button.setImage(image, forState: .Normal)
button.addTarget(self, action: "btnTouched:", forControlEvents:.TouchUpInside)

Wi-Fi Direct and iOS Support

It took me a while to find out what is going on, but here is the summary. I hope this save people a lot of time.

Apple are not playing nice with Wi-Fi Direct, not in the same way that Android is. The Multipeer Connectivity Framework that Apple provides combines both BLE and WiFi Direct together and will only work with Apple devices and not any device that is using Wi-Fi Direct.

It states the following in this documentation - "The Multipeer Connectivity framework provides support for discovering services provided by nearby iOS devices using infrastructure Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks and subsequently communicating with those services by sending message-based data, streaming data, and resources (such as files)."

Additionally, Wi-Fi direct in this mode between i-Devices will need iPhone 5 and above.

There are apps that use a form of Wi-Fi Direct on the App Store, but these are using their own libraries.

Java socket API: How to tell if a connection has been closed?

I see the other answer just posted, but I think you are interactive with clients playing your game, so I may pose another approach (while BufferedReader is definitely valid in some cases).

If you wanted to... you could delegate the "registration" responsibility to the client. I.e. you would have a collection of connected users with a timestamp on the last message received from each... if a client times out, you would force a re-registration of the client, but that leads to the quote and idea below.

I have read that to actually determine whether or not a socket has been closed data must be written to the output stream and an exception must be caught. This seems like a really unclean way to handle this situation.

If your Java code did not close/disconnect the Socket, then how else would you be notified that the remote host closed your connection? Ultimately, your try/catch is doing roughly the same thing that a poller listening for events on the ACTUAL socket would be doing. Consider the following:

  • your local system could close your socket without notifying you... that is just the implementation of Socket (i.e. it doesn't poll the hardware/driver/firmware/whatever for state change).
  • new Socket(Proxy p)... there are multiple parties (6 endpoints really) that could be closing the connection on you...

I think one of the features of the abstracted languages is that you are abstracted from the minutia. Think of the using keyword in C# (try/finally) for SqlConnection s or whatever... it's just the cost of doing business... I think that try/catch/finally is the accepted and necesary pattern for Socket use.

fatal: 'origin' does not appear to be a git repository

This does not answer your question, but I faced a similar error message but due to a different reason. Allow me to make my post for the sake of information collection.

I have a git repo on a network drive. Let's call this network drive RAID. I cloned this repo on my local machine (LOCAL) and on my number crunching cluster (CRUNCHER). For convenience I mounted the user directory of my account on CRUNCHER on my local machine. So, I can manipulate files on CRUNCHER without the need to do the work in an SSH terminal.

Today, I was modifying files in the repo on CRUNCHER via my local machine. At some point I decided to commit the files, so a did a commit. Adding the modified files and doing the commit worked as I expected, but when I called git push I got an error message similar to the one posted in the question.

The reason was, that I called push from within the repo on CRUNCHER on LOCAL. So, all paths in the config file were plain wrong.

When I realized my fault, I logged onto CRUNCHER via Terminal and was able to push the commit.

Feel free to comment if my explanation can't be understood, or you find my post superfluous.

How to Uninstall RVM?

It’s easy; just do the following:

rvm implode


rm -rf ~/.rvm

And don’t forget to remove the script calls in the following files:

  • ~/.bashrc
  • ~/.bash_profile
  • ~/.profile

And maybe others depending on whatever shell you’re using.

html select scroll bar

Horizontal scrollbars in a HTML Select are not natively supported. However, here's a way to create the appearance of a horizontal scrollbar:

1. First create a css class

<style type="text/css">
   overflow: auto;
   width: 70px; /* adjust this width depending to amount of text to display */
   height: 80px; /* adjust height depending on number of options to display */
   border: 1px silver solid;
 .scrollable select{
   border: none;

2. Wrap the SELECT inside a DIV - also, explicitly set the size to the number of options.

<div class="scrollable">
<select size="6" multiple="multiple">
    <option value="1" selected>option 1 The Long Option</option>
    <option value="2">option 2</option>
    <option value="3">option 3</option>
    <option value="4">option 4</option>
    <option value="5">option 5 Another Longer than the Long Option ;)</option>
    <option value="6">option 6</option>

Try catch statements in C

Ok, I couldn't resist replying to this. Let me first say I don't think it's a good idea to simulate this in C as it really is a foreign concept to C.

We can use abuse the preprocessor and local stack variables to give use a limited version of C++ try/throw/catch.

Version 1 (local scope throws)

#include <stdbool.h>

#define try bool __HadError=false;
#define catch(x) ExitJmp:if(__HadError)
#define throw(x) __HadError=true;goto ExitJmp;

Version 1 is a local throw only (can't leave the function's scope). It does rely on C99's ability to declare variables in code (it should work in C89 if the try is first thing in the function).

This function just makes a local var so it knows if there was an error and uses a goto to jump to the catch block.

For example:

#include <stdio.h>
#include <stdbool.h>

#define try bool __HadError=false;
#define catch(x) ExitJmp:if(__HadError)
#define throw(x) __HadError=true;goto ExitJmp;

int main(void)
    return 0;

This works out to something like:

int main(void)
    bool HadError=false;
        goto ExitJmp;
    return 0;

Version 2 (scope jumping)

#include <stdbool.h>
#include <setjmp.h>

jmp_buf *g__ActiveBuf;

#define try jmp_buf __LocalJmpBuff;jmp_buf *__OldActiveBuf=g__ActiveBuf;bool __WasThrown=false;g__ActiveBuf=&__LocalJmpBuff;if(setjmp(__LocalJmpBuff)){__WasThrown=true;}else
#define catch(x) g__ActiveBuf=__OldActiveBuf;if(__WasThrown)
#define throw(x) longjmp(*g__ActiveBuf,1);

Version 2 is a lot more complex but basically works the same way. It uses a long jump out of the current function to the try block. The try block then uses an if/else to skip the code block to the catch block which check the local variable to see if it should catch.

The example expanded again:

jmp_buf *g_ActiveBuf;

int main(void)
    jmp_buf LocalJmpBuff;
    jmp_buf *OldActiveBuf=g_ActiveBuf;
    bool WasThrown=false;

    return 0;

This uses a global pointer so the longjmp() knows what try was last run. We are using abusing the stack so child functions can also have a try/catch block.

Using this code has a number of down sides (but is a fun mental exercise):

  • It will not free allocated memory as there are no deconstructors being called.
  • You can't have more than 1 try/catch in a scope (no nesting)
  • You can't actually throw exceptions or other data like in C++
  • Not thread safe at all
  • You are setting up other programmers for failure because they will likely not notice the hack and try using them like C++ try/catch blocks.

How do you represent a JSON array of strings?

String strJson="{\"Employee\":

This is an example of a JSON string with Employee as object, then multiple strings and values in an array as a reference to @cregox...

A bit complicated but can explain a lot in a single JSON string.

How to pick a new color for each plotted line within a figure in matplotlib?

matplotlib 1.5+

You can use axes.set_prop_cycle (example).

matplotlib 1.0-1.4

You can use axes.set_color_cycle (example).

matplotlib 0.x

You can use Axes.set_default_color_cycle.

UTF-8 encoding in JSP page

I had the same problem using special characters as delimiters on JSP. When the special characters got posted to the servlet, they all got messed up. I solved the issue by using the following conversion:

String str = new String (request.getParameter("string").getBytes ("iso-8859-1"), "UTF-8");

Google Maps API Multiple Markers with Infowindows

If you also want to bind closing of infowindow to some event, try something like this

google.maps.event.addListener(marker,'click', (function(marker,content,infowindow){ 
    return function() {
        google.maps.event.addListener(map,'click', function(){ 

resource error in android studio after update: No Resource Found

First of all,

Try to check your SDK folder, for me, it was mydocuments/appdata/sdk.... etc. So basically my sdk folder was not fully downloaded, the source of this problem mainly. You have to either use another fully downloaded android sdk(including Tools section and extras that you really need) or use the eclipse sdk that you may downloaded earlier for your Eclipse android developments. Then build->clean your project once again.

Worth to try.

ASP.NET MVC: What is the purpose of @section?

You want to use sections when you want a bit of code/content to render in a placeholder that has been defined in a layout page.

In the specific example you linked, he has defined the RenderSection in the _Layout.cshtml. Any view that uses that layout can define an @section of the same name as defined in Layout, and it will replace the RenderSection call in the layout.

Perhaps you're wondering how we know Index.cshtml uses that layout? This is due to a bit of MVC/Razor convention. If you look at the dialog where he is adding the view, the box "Use layout or master page" is checked, and just below that it says "Leave empty if it is set in a Razor _viewstart file". It isn't shown, but inside that _ViewStart.cshtml file is code like:

    Layout = "~/Views/Shared/_Layout.cshtml";

The way viewstarts work is that any cshtml file within the same directory or child directories will run the ViewStart before it runs itself.

Which is what tells us that Index.cshtml uses Shared/_Layout.cshtml.

How to printf uint64_t? Fails with: "spurious trailing ‘%’ in format"

Since you've included the C++ tag, you could use the {fmt} library and avoid the PRIu64 macro and other printf issues altogether:

#include <fmt/core.h>

int main() {
  uint64_t ui64 = 90;
  fmt::print("test uint64_t : {}\n", ui64);

The formatting facility based on this library is proposed for standardization in C++20: P0645.

Disclaimer: I'm the author of {fmt}.

What is the best way to add options to a select from a JavaScript object with jQuery?

  1. $.each is slower than a for loop
  2. Each time, a DOM selection is not the best practice in loop $("#mySelect").append();

So the best solution is the following

If JSON data resp is

    {"id":"0001", "name":"Mr. P"},
    {"id":"0003", "name":"Mr. Q"},
    {"id":"0054", "name":"Mr. R"},
    {"id":"0061", "name":"Mr. S"}

use it as

var option = "";
for (i=0; i<resp.length; i++) {
    option += "<option value='" + resp[i].id + "'>" + resp[i].name + "</option>";

Fatal error: unexpectedly found nil while unwrapping an Optional values

fatal error: unexpectedly found nil while unwrapping an Optional value

  1. Check the IBOutlet collection , because this error will have chance to unconnected uielement object usage.

:) hopes it will help for some struggled people .

Make xargs execute the command once for each line of input

If you want to run the command for every line (i.e. result) coming from find, then what do you need the xargs for?


find path -type f -exec your-command {} \;

where the literal {} gets substituted by the filename and the literal \; is needed for find to know that the custom command ends there.


(after the edit of your question clarifying that you know about -exec)

From man xargs:

-L max-lines
Use at most max-lines nonblank input lines per command line. Trailing blanks cause an input line to be logically continued on the next input line. Implies -x.

Note that filenames ending in blanks would cause you trouble if you use xargs:

$ mkdir /tmp/bax; cd /tmp/bax
$ touch a\  b c\  c
$ find . -type f -print | xargs -L1 wc -l
0 ./c
0 ./c
0 total
0 ./b
wc: ./a: No such file or directory

So if you don't care about the -exec option, you better use -print0 and -0:

$ find . -type f -print0 | xargs -0L1 wc -l
0 ./c
0 ./c
0 ./b
0 ./a

How to reference Microsoft.Office.Interop.Excel dll?

If you have VS 2013 Express and you cant find Microsoft.Office namespace, try this ('Microsoft Excel 12.0 Object Library' if you want to use Office 2007)

enter image description here

Pivoting rows into columns dynamically in Oracle

Oracle 11g provides a PIVOT operation that does what you want.

Oracle 11g solution

select * from
(select id, k, v from _kv) 
pivot(max(v) for k in ('name', 'age', 'gender', 'status')

(Note: I do not have a copy of 11g to test this on so I have not verified its functionality)

I obtained this solution from:

EDIT -- pivot xml option (also Oracle 11g)
Apparently there is also a pivot xml option for when you do not know all the possible column headings that you may need. (see the XML TYPE section near the bottom of the page located at

select * from
(select id, k, v from _kv) 
pivot xml (max(v)
for k in (any) )

(Note: As before I do not have a copy of 11g to test this on so I have not verified its functionality)

Edit2: Changed v in the pivot and pivot xml statements to max(v) since it is supposed to be aggregated as mentioned in one of the comments. I also added the in clause which is not optional for pivot. Of course, having to specify the values in the in clause defeats the goal of having a completely dynamic pivot/crosstab query as was the desire of this question's poster.

Couldn't load memtrack module Logcat Error

I had this issue too, also running on an emulator.. The same message was showing up on Logcat, but it wasn't affecting the functionality of the app. But it was annoying, and I don't like seeing errors on the log that I don't understand.

Anyway, I got rid of the message by increasing the RAM on the emulator.

Convert List to Pandas Dataframe Column


L = ['Thanks You', 'Its fine no problem', 'Are you sure']

#create new df 
df = pd.DataFrame({'col':L})
print (df)

0           Thanks You
1  Its fine no problem
2         Are you sure

df = pd.DataFrame({'oldcol':[1,2,3]})

#add column to existing df 
df['col'] = L
print (df)
   oldcol                  col
0       1           Thanks You
1       2  Its fine no problem
2       3         Are you sure

Thank you DYZ:

#default column name 0
df = pd.DataFrame(L)
print (df)
0           Thanks You
1  Its fine no problem
2         Are you sure

HTTP Status 500 - org.apache.jasper.JasperException: java.lang.NullPointerException

NullPointerException with JSP can also happen if:

A getter returns a non-public inner class.

This code will fail if you remove Getters's access modifier or make it private or protected.


package com.myPackage;
public class MyClass{ 
    //: Must be public or you will get:
    //: org.apache.jasper.JasperException: 
    //: java.lang.NullPointerException
    public class Getters{
        public String 
        myProperty(){ return(my_property); }

    //: JSP EL can only access functions:
    private Getters _get;
    public  Getters  get(){ return _get; }

    private String 

    public MyClass(String my_property){
        this.my_property    = my_property;
        _get = new Getters();


<%@ taglib uri   ="" prefix="c" %>
<%@ page import="com.myPackage.MyClass" %>
    MyClass inst = new MyClass("[PROP_VALUE]");
    pageContext.setAttribute("my_inst", inst ); 
%><html lang="en"><body>
    ${ my_inst.get().myProperty() }

Add JavaScript object to JavaScript object

As my first object is a native javascript object (used like a list of objects), push didn't work in my escenario, but I resolved it by adding new key as following:

MyObjList['newKey'] = obj;

In addition to this, may be usefull to know how to delete same object inserted before:

delete MyObjList['newKey'][id];

Hope it helps someone as it helped me;

Left Outer Join using + sign in Oracle 11g

I saw some contradictions in the answers above, I just tried the following on Oracle 12c and the following is correct :


WHERE A.column = B.column(+)


WHERE B.column(+) = A.column

Horizontal scroll css?

Just set your width to auto:

    width: auto;
    border: 13px solid #bed5cd;
    overflow-x: scroll;
    overflow-y: hidden;
    white-space: nowrap;

This way your div can be as wide as possible, so you can add as many kitty images as possible ;3

Your div's width will expand based on the child elements it contains.


How do I add a newline to a TextView in Android?

My 2 cents, using Android TV.

Add \n in XML strings, while reading:

public void setSubtitle(String subtitle) {
    this.subtitle = subtitle.replace("\\n", System.getProperty("line.separator"));

Free c# QR-Code generator

Take a look QRCoder - pure C# open source QR code generator. Can be used in three lines of code

QRCodeGenerator qrGenerator = new QRCodeGenerator();
QRCodeGenerator.QRCode qrCode = qrGenerator.CreateQrCode(textBoxQRCode.Text, QRCodeGenerator.ECCLevel.Q);
pictureBoxQRCode.BackgroundImage = qrCode.GetGraphic(20);

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"

What is path of JDK on Mac ?


Also see Java 7 path on mountain lion

Run a batch file with Windows task scheduler

It is working now. This is what I did. You probably won't need all these steps to make it work but just to be sure try them all:

  • Check the account parameters of your scheduled task and make sure they are set to run whether or not someone is logged into the machine

  • check run with most privileges/rights

  • Make sure you go to the full path first: cd C:\inetpub\wwwroot\infoweb\factuur\cron

  • Don't use double quotes in your batch files (don't know why but seems to help)

  • Be super admin, enter 'Net user administrator /active:yes' in command prompt, log out and log in as the super admin, so UAC is off

How to create a zip archive with PowerShell?

Here is a slightly improved version of sonjz's answer,it adds an overwrite option.

function Zip-Files(
        [Parameter(Position=0, Mandatory=$true, ValueFromPipeline=$false)]
        [string] $zipfilename,
        [Parameter(Position=1, Mandatory=$true, ValueFromPipeline=$false)]
        [string] $sourcedir,
        [Parameter(Position=2, Mandatory=$false, ValueFromPipeline=$false)]
        [bool] $overwrite)

   Add-Type -Assembly System.IO.Compression.FileSystem
   $compressionLevel = [System.IO.Compression.CompressionLevel]::Optimal

    if ($overwrite -eq $true )
        if (Test-Path $zipfilename)
            Remove-Item $zipfilename

    [System.IO.Compression.ZipFile]::CreateFromDirectory($sourcedir, $zipfilename, $compressionLevel, $false)

How to detect idle time in JavaScript elegantly?

You could probably hack something together by detecting mouse movement on the body of the form and updating a global variable with the last movement time. You'd then need to have an interval timer running that periodically checks the last movement time and does something if it has been sufficiently long since the last mouse movement was detected.


My explanation is in the code. :)

DECLARE @TestConvert VARCHAR(MAX) = '123456789.1234567'
    SELECT CAST(@TestConvert AS DECIMAL(10, 4))
    SELECT 'The reason you get the message "' + ERROR_MESSAGE() + '" is because DECIMAL(10, 4) only allows for 4 numbers after the decimal.'

-- Here's one way to truncate the string to a castable value.
SELECT CAST(LEFT(@TestConvert, (CHARINDEX('.', @TestConvert, 1) + 4)) AS DECIMAL(14, 4))

-- If you noticed, I changed it to DECIMAL(14, 4) instead of DECIMAL(10, 4) That's because this number has 14 digits, as proven below.
-- Read this for a better explanation as to what precision, scale and length mean:
SELECT LEN(LEFT(@TestConvert, (CHARINDEX('.', @TestConvert, 1) + 4)))

How to use relative/absolute paths in css URLs?

i had the same problem... every time that i wanted to publish my css.. I had to make a search/replace.. and relative path wouldnt work either for me because the relative paths were different from dev to production.

Finally was tired of doing the search/replace and I created a dynamic css, (e.g. it's the same but now i could use my php constants in the css. somethig like

  background-image:url('<?php echo BASE_IMAGE;?>icon.png');

and it's not a bad idea to make it dynamic because now i could compress it using YUI compressor without loosing the original format on my dev server.

Good Luck!

Is iterating ConcurrentHashMap values thread safe?

It means that you should not share an iterator object among multiple threads. Creating multiple iterators and using them concurrently in separate threads is fine.

How to terminate a process in vbscript

Just type in the following command: taskkill /f /im (program name) To find out the im of your program open task manager and look at the process while your program is running. After the program has run a process will disappear from the task manager; that is your program.

What is a file with extension .a?

.a files are created with the ar utility, and they are libraries. To use it with gcc, collect all .a files in a lib/ folder and then link with -L lib/ and -l<name of specific library>.

Collection of all .a files into lib/ is optional. Doing so makes for better looking directories with nice separation of code and libraries, IMHO.

Creating a jQuery object from a big HTML-string

As of jQuery 1.8 you can just use parseHtml to create your jQuery object:

var myString = "<div>Some stuff<div>Some more stuff<span id='theAnswer'>The stuff I am looking for</span></div></div>";
var $jQueryObject = $($.parseHTML(myString));

I've created a JSFidle that demonstrates this:

It parses the arbitrary HTML string into a jQuery object, and uses find to display the result in a div.

Change the color of glyphicons to blue in some- but not at all places using Bootstrap 2

Bootstrap >= v4.0 dropped glyphicon support

Dropped the Glyphicons icon font. If you need icons, some options are:

the upstream version of Glyphicons


Font Awesome


If you are using Bootstrap >= v4.0 or newer, you can use existing style classes of bootstrap such as text-success,text-warning etc.

For example, if you are using fontawesome:

<i class="fa fa-tag text-danger" aria-hidden="true"></i>

Chrome hangs after certain amount of data transfered - waiting for available socket

Our first thought is that the site is down or the like, but the truth is that this is not the problem or disability. Nor is it a problem because a simple connection when tested under Firefox, Opera or services Explorer open as normal.

The error in Chrome displays a sign that says "This site is not available" and clarification with the legend "Error 15 (net :: ERR_SOCKET_NOT_CONNECTED): Unknown error". The error is quite usual in Google Chrome, more precisely in its updates, and its workaround is to restart the computer.

As partial solutions are not much we offer a tutorial for you solve the fault in less than a minute. To avoid this problem and ensure that services are normally open in Google Chrome should insert the following into the address bar: chrome: // net-internals (then give "Enter"). They then have to go to the "Socket" in the left menu and choose "Flush Socket Pools" (look at the following screenshots to guide This has the problem solved and no longer will experience problems accessing Gmail, Google or any of the services of the Mountain View giant. I hope you found it useful and share the tutorial with whom they need or social networks: Facebook, Twitter or Google+.

google console error `OR-IEH-01`

It looks like your Google Play registration payment didn’t process. This can happen sometimes if a card has expired, the credit card or credit card verification (CVC) number was entered incorrectly, or if your billing address doesn't match the address in your Google Payments account.

Here’s how you can find the details of your transaction:

  1. Sign in to your Google Payments account at

  2. On the left menu, select the “Subscriptions and services” page.

  3. On the “Other purchase activity” card, click View purchases.

  4. Click the “Google Play” registration transaction to see your payment method.

  5. You can click “Payment methods” on the left menu if you need to edit the addresses on your Google Payments account.

To add a new credit or debit card to your account, you can follow the instructions on the Google Payments Help Center (

Render HTML to an image

Install phantomjs

$ npm install phantomjs

Create a file github.js with following code

var page = require('webpage').create();
//viewportSize being the actual size of the headless browser
page.viewportSize = { width: 1024, height: 768 };'', function() {

Pass the file as argument to phantomjs

$ phantomjs github.js

Bad File Descriptor with Linux Socket write() Bad File Descriptor C

The value you have passed as the file descriptor is not valid. It is either negative or does not represent a currently open file or socket.

So you have either closed the socket before calling write() or you have corrupted the value of 'sockfd' somewhere in your code.

It would be useful to trace all calls to close(), and the value of 'sockfd' prior to the write() calls.

Your technique of only printing error messages in debug mode seems to me complete madness, and in any case calling another function between a system call and perror() is invalid, as it may disturb the value of errno. Indeed it may have done so in this case, and the real underlying error may be different.

Using dig to search for SPF records

I believe that I found the correct answer through this dig How To. I was able to look up the SPF records on a specific DNS, by using the following query:

dig txt

Creating the Singleton design pattern in PHP5

This is the example of create singleton on Database class

design patterns 1) singleton

class Database{
  public static $instance;
  public static function getInstance(){
    Database::$instance=new Database();

     return Database::$instance;




then out put is --


use only single instance not create 3 instance

Read lines from a text file but skip the first two lines

Dim sFileName As String
Dim iFileNum As Integer
Dim sBuf As String
Dim Fields as String
Dim TempStr as String

sFileName = "c:\fields.ini"
''//Does the file exist?
If Len(Dir$(sFileName)) = 0 Then
    MsgBox ("Cannot find fields.ini")
End If

iFileNum = FreeFile()
Open sFileName For Input As iFileNum

''//This part skips the first two lines
if not(EOF(iFileNum)) Then Line Input #iFilenum, TempStr
if not(EOF(iFileNum)) Then Line Input #iFilenum, TempStr

Do While Not EOF(iFileNum)
    Line Input #iFileNum, Fields

    MsgBox (Fields)

ReactJS - Call One Component Method From Another Component

You can do something like this

import React from 'react';

class Header extends React.Component {

constructor() {

checkClick(e, notyId) {

render() {
    return (
        <PopupOver func ={this.checkClick } />

class PopupOver extends React.Component {

constructor(props) {
    this.props.func(this, 1234);

render() {
    return (
        <div className="displayinline col-md-12 ">

export default Header;

Using statics

var MyComponent = React.createClass({
 statics: {
 customMethod: function(foo) {
  return foo === 'bar';
   render: function() {

MyComponent.customMethod('bar');  // true

Upgrade to python 3.8 using conda

You can update your python version to 3.8 in conda using the command

conda install -c anaconda python=3.8

as per Though not all packages support 3.8 yet, running

conda update --all

may resolve some dependency failures. You can also create a new environment called py38 using this command

conda create -n py38 python=3.8

Edit - note that the conda install option will potentially take a while to solve the environment, and if you try to abort this midway through you will lose your Python installation (usually this means it will resort to non-conda pre-installed system Python installation).

Reading e-mails from Outlook with Python through MAPI

I have created my own iterator to iterate over Outlook objects via python. The issue is that python tries to iterates starting with Index[0], but outlook expects for first item Index[1]... To make it more Ruby simple, there is below a helper class Oli with following methods:

.items() - yields a tuple(index, Item)...

.prop() - helping to introspect outlook object exposing available properties (methods and attributes)

from win32com.client import constants
from win32com.client.gencache import EnsureDispatch as Dispatch

outlook = Dispatch("Outlook.Application")
mapi = outlook.GetNamespace("MAPI")

class Oli():
    def __init__(self, outlook_object):
        self._obj = outlook_object

    def items(self):
        array_size = self._obj.Count
        for item_index in xrange(1,array_size+1):
            yield (item_index, self._obj[item_index])

    def prop(self):
        return sorted( self._obj._prop_map_get_.keys() )

for inx, folder in Oli(mapi.Folders).items():
    # iterate all Outlook folders (top level)
    print "-"*70
    print folder.Name

    for inx,subfolder in Oli(folder.Folders).items():
        print "(%i)" % inx, subfolder.Name,"=> ", subfolder

Return empty cell from formula in Excel

Excel does not have any way to do this.

The result of a formula in a cell in Excel must be a number, text, logical (boolean) or error. There is no formula cell value type of "empty" or "blank".

One practice that I have seen followed is to use NA() and ISNA(), but that may or may not really solve your issue since there is a big differrence in the way NA() is treated by other functions (SUM(NA()) is #N/A while SUM(A1) is 0 if A1 is empty).

Laravel 5 – Clear Cache in Shared Hosting Server

Try this also

for cli

php artisan clear:cache

for use artisan command

 Route::get('/clear-cache', function() {
 $exitCode = Artisan::call('cache:clear');
 return 'Application cache cleared';




getColor(int id) deprecated on Android 6.0 Marshmallow (API 23)

In Kotlin, you can do:

ContextCompat.getColor(requireContext(), R.color.stage_hls_fallback_snackbar)

if requireContext() is accessible from where you are calling the function. I was getting an error when trying

ContextCompat.getColor(context, R.color.stage_hls_fallback_snackbar)

ngOnInit not being called when Injectable class is Instantiated

import {Injectable, OnInit} from 'angular2/core';
import { RestApiService, RestRequest } from './rest-api.service';
import {Service} from "path/to/service/";

export class MovieDbService implements OnInit {


constructor(private _movieDbRest: RestApiService,
            private instanceMyService : Service ){

   // do evreything like OnInit just on services


   this.userId = this.instanceMyService.getUserId()


MongoDB Aggregation: How to get total records count?

Here are some ways to get total records count while doing MongoDB Aggregation:

  • Using $count:

       // Other stages here
       { $count: "Total" }

    For getting 1000 records this takes on average 2 ms and is the fastest way.

  • Using .toArray():


    For getting 1000 records this takes on average 18 ms.

  • Using .itcount():


    For getting 1000 records this takes on average 14 ms.

Merge, update, and pull Git branches without using checkouts

Another, admittedly pretty brute way is to just re-create the branch:

git fetch remote
git branch -f localbranch remote/remotebranch

This throws away the local outdated branch and re-creates one with the same name, so use with care ...

How to declare a Fixed length Array in TypeScript

The javascript array has a constructor that accepts the length of the array:

let arr = new Array<number>(3);
console.log(arr); // [undefined × 3]

However, this is just the initial size, there's no restriction on changing that:

console.log(arr); // [undefined × 3, 5]

Typescript has tuple types which let you define an array with a specific length and types:

let arr: [number, number, number];

arr = [1, 2, 3]; // ok
arr = [1, 2]; // Type '[number, number]' is not assignable to type '[number, number, number]'
arr = [1, 2, "3"]; // Type '[number, number, string]' is not assignable to type '[number, number, number]'

How to output loop.counter in python jinja template?

in python:

env = Environment(loader=FileSystemLoader("templates"))
env.globals["enumerate"] = enumerate

in template:

{% for k,v in enumerate(list) %}
{% endfor %}

Java way to check if a string is palindrome

public static boolean istPalindrom(char[] word){
int i1 = 0;
int i2 = word.length - 1;
while (i2 > i1) {
    if (word[i1] != word[i2]) {
        return false;
return true;

spring data jpa @query and pageable

Considering that the UrnMapping class is mapped to the internal_uddi table, I would suggest this:

public interface UrnMappingRepository extends JpaRepository<UrnMapping, Long> {

    @Query(value = "select iu from UrnMapping iu where iu.urn like %:text% or like %:text%")
    Page<UrnMapping> fullTextSearch(@Param("text") String text, Pageable pageable);

Please note that you might have to turn off native queries with dynamic requests.

How to copy directories in OS X 10.7.3?


cp -R "/src/project 1/App" "/src/project 2"


Using quotes will cater for spaces in the directory names

cp -R "/src/project 1/App" "/src/project 2"

If the App directory is specified in the destination directory:

cp -R "/src/project 1/App" "/src/project 2/App"

and "/src/project 2/App" already exists the result will be "/src/project 2/App/App"

Best not to specify the directory copied in the destination so that the command can be repeated over and over with the expected result.

Inside a bash script:

cp -R "${1}/App" "${2}"

Remove element by id

The ChildNode.remove() method removes the object from the tree it belongs to.

Here is a fiddle that shows how you can call document.getElementById('my-id').remove()


There is no need to extend NodeList. It has been implemented already.


sql select with column name like

SELECT * FROM SysColumns WHERE Name like 'a%'

Will get you a list of columns, you will want to filter more to restrict it to your target table

From there you can construct some ad-hoc sql

Put search icon near textbox using bootstrap

Here are three different ways to do it:


Here's a working Demo in Fiddle Of All Three


You can use native bootstrap validation states (No Custom CSS!):

<div class="form-group has-feedback">
    <label class="control-label" for="inputSuccess2">Name</label>
    <input type="text" class="form-control" id="inputSuccess2"/>
    <span class="glyphicon glyphicon-search form-control-feedback"></span>

For a full discussion, see my answer to Add a Bootstrap Glyphicon to Input Box

Input Group:

You can use the .input-group class like this:

<div class="input-group">
    <input type="text" class="form-control"/>
    <span class="input-group-addon">
        <i class="fa fa-search"></i>

For a full discussion, see my answer to adding Twitter Bootstrap icon to Input box

Unstyled Input Group:

You can still use .input-group for positioning but just override the default styling to make the two elements appear separate.

Use a normal input group but add the class input-group-unstyled:

<div class="input-group input-group-unstyled">
    <input type="text" class="form-control" />
    <span class="input-group-addon">
        <i class="fa fa-search"></i>

Then change the styling with the following css:

.input-group.input-group-unstyled input.form-control {
    -webkit-border-radius: 4px;
       -moz-border-radius: 4px;
            border-radius: 4px;
.input-group-unstyled .input-group-addon {
    border-radius: 4px;
    border: 0px;
    background-color: transparent;

Also, these solutions work for any input size

How do I add a user when I'm using Alpine as a base image?

The commands are adduser and addgroup.

Here's a template for Docker you can use in busybox environments (alpine) as well as Debian-based environments (Ubuntu, etc.):

ENV USER=docker
ENV UID=12345
ENV GID=23456

RUN adduser \
    --disabled-password \
    --gecos "" \
    --home "$(pwd)" \
    --ingroup "$USER" \
    --no-create-home \
    --uid "$UID" \

Note the following:

  • --disabled-password prevents prompt for a password
  • --gecos "" circumvents the prompt for "Full Name" etc. on Debian-based systems
  • --home "$(pwd)" sets the user's home to the WORKDIR. You may not want this.
  • --no-create-home prevents cruft getting copied into the directory from /etc/skel

The usage description for these applications is missing the long flags present in the code for adduser and addgroup.

The following long-form flags should work both in alpine as well as debian-derivatives:


BusyBox v1.28.4 (2018-05-30 10:45:57 UTC) multi-call binary.

Usage: adduser [OPTIONS] USER [GROUP]

Create new user, or add USER to GROUP

        --home DIR           Home directory
        --gecos GECOS        GECOS field
        --shell SHELL        Login shell
        --ingroup GRP        Group (by name)
        --system             Create a system user
        --disabled-password  Don't assign a password
        --no-create-home     Don't create home directory
        --uid UID            User id

One thing to note is that if --ingroup isn't set then the GID is assigned to match the UID. If the GID corresponding to the provided UID already exists adduser will fail.


BusyBox v1.28.4 (2018-05-30 10:45:57 UTC) multi-call binary.

Usage: addgroup [-g GID] [-S] [USER] GROUP

Add a group or add a user to a group

        --gid GID  Group id
        --system   Create a system group

I discovered all of this while trying to write my own alternative to the fixuid project for running containers as the hosts UID/GID.

My entrypoint helper script can be found on GitHub.

The intent is to prepend that script as the first argument to ENTRYPOINT which should cause Docker to infer UID and GID from a relevant bind mount.

An environment variable "TEMPLATE" may be required to determine where the permissions should be inferred from.

(At the time of writing I don't have documentation for my script. It's still on the todo list!!)

How to create a shared library with cmake?

Always specify the minimum required version of cmake

cmake_minimum_required(VERSION 3.9)

You should declare a project. cmake says it is mandatory and it will define convenient variables PROJECT_NAME, PROJECT_VERSION and PROJECT_DESCRIPTION (this latter variable necessitate cmake 3.9):

project(mylib VERSION 1.0.1 DESCRIPTION "mylib description")

Declare a new library target. Please avoid the use of file(GLOB ...). This feature does not provide attended mastery of the compilation process. If you are lazy, copy-paste output of ls -1 sources/*.cpp :

add_library(mylib SHARED

Set VERSION property (optional but it is a good practice):

set_target_properties(mylib PROPERTIES VERSION ${PROJECT_VERSION})

You can also set SOVERSION to a major number of VERSION. So will be a symlink to

set_target_properties(mylib PROPERTIES SOVERSION 1)

Declare public API of your library. This API will be installed for the third-party application. It is a good practice to isolate it in your project tree (like placing it include/ directory). Notice that, private headers should not be installed and I strongly suggest to place them with the source files.

set_target_properties(mylib PROPERTIES PUBLIC_HEADER include/mylib.h)

If you work with subdirectories, it is not very convenient to include relative paths like "../include/mylib.h". So, pass a top directory in included directories:

target_include_directories(mylib PRIVATE .)


target_include_directories(mylib PRIVATE include)
target_include_directories(mylib PRIVATE src)

Create an install rule for your library. I suggest to use variables CMAKE_INSTALL_*DIR defined in GNUInstallDirs:


And declare files to install:

install(TARGETS mylib

You may also export a pkg-config file. This file allows a third-party application to easily import your library:

Create a template file named (see pc(5) manpage for more information):



Libs: -L${libdir} -lmylib
Cflags: -I${includedir}

In your CMakeLists.txt, add a rule to expand @ macros (@ONLY ask to cmake to not expand variables of the form ${VAR}):

configure_file( mylib.pc @ONLY)

And finally, install generated file:


You may also use cmake EXPORT feature. However, this feature is only compatible with cmake and I find it difficult to use.

Finally the entire CMakeLists.txt should looks like:

cmake_minimum_required(VERSION 3.9)
project(mylib VERSION 1.0.1 DESCRIPTION "mylib description")
add_library(mylib SHARED src/mylib.c)
set_target_properties(mylib PROPERTIES
    PUBLIC_HEADER api/mylib.h)
configure_file( mylib.pc @ONLY)
target_include_directories(mylib PRIVATE .)
install(TARGETS mylib
install(FILES ${CMAKE_BINARY_DIR}/mylib.pc

If Else If In a Sql Server Function

If yes_ans > no_ans and yes_ans > na_ans  

You're using column names in a statement (outside of a query). If you want variables, you must declare and assign them.

CodeIgniter: 404 Page Not Found on Live Server

Please check the root/application/core/ folder files whether if you have used any of MY_Loader.php, MY_Parser.php or MY_Router.php files.

If so, please try by removing above files from the folder and check whether that make any difference. In fact, just clean that folder by just keeping the default index.html file.

I have found these files caused the issue to route to the correct Controller's functions.

Hope that helps!

Javascript - How to show escape characters in a string?

You have to escape the backslash, so try this:

str = "Hello\\nWorld";

Here are more escaped characters in Javascript.

Why does Vim save files with a ~ extension?

Put this line into your vimrc:

set nobk nowb noswf noudf " nobackup nowritebackup noswapfile noundofile

In that would be the:

C:\Program Files (x86)\vim\_vimrc

file for system-wide vim configuration for all users.

Setting the last one noundofile is important in Windows to prevent the creation of *~ tilda files after editing.

I wish Vim had that line included by default. Nobody likes ugly directories.

Let the user choose if and how she wants to enable advanced backup/undo file features first.

This is the most annoying part of Vim.

The next step might be setting up:

set noeb vb t_vb= " errorbells visualbell

to disable beeping in as well :-)

Show SOME invisible/whitespace characters in Eclipse

Unfortunately, you can only turn on all invisible (whitespace) characters at the same time. I suggest you file an enhancement request but I doubt they will pick it up.

The text component in Eclipse is very complicated as it is and they are not keen on making them even worse.

[UPDATE] This has been fixed in Eclipse 3.7: Go to Window > Preferences > General > Editors > Text Editors

Click on the link "whitespace characters" to fine tune what should be shown.

Kudos go to John Isaacks

How do I hide an element on a click event anywhere outside of the element?

Here is a working CSS/small JS solution based on the answer of Sandeep Pal:

$(document).click(function (e)
  if (!$("#noticeMenu").is( && $("#noticeMenu").has( == 0)
   $("#menu-toggle3").prop('checked', false);

Try it out by clicking the checkbox and then outside of the menu:

How to disable scientific notation?

You can effectively remove scientific notation in printing with this code:


How do I declare a two dimensional array?

Just declare? You don't have to. Just make sure variable exists:

$d = array();

Arrays are resized dynamically, and attempt to write anything to non-exsistant element creates it (and creates entire array if needed)

$d[1][2] = 3;

This is valid for any number of dimensions without prior declarations.

How to pass parameters in $ajax POST?

      type: 'post',
      url: 'superman',
      data: { 
        "field1": "hello",
        "field2": "hello1"
      success: function (response) {
        alert("Success !!");
      error: function () {
        alert("Error !!");

type: 'POST', will append **parameters to the body of the request** which is not seen in the URL while type: 'GET', appends parameters to the URL which is visible.

Most of the popular web browsers contain network panels which displays the complete request.

In network panel select XHR to see requests.

This can also be done via this.

        'field1': 'hello', 
        'field2': 'hello1'
      function (response) {
        alert("Success !");

What is ANSI format?

Technically, ANSI should be the same as US-ASCII. It refers to the ANSI X3.4 standard, which is simply the ANSI organisation's ratified version of ASCII. Use of the top-bit-set characters is not defined in ASCII/ANSI as it is a 7-bit character set.

However years of misuse of the term by the DOS and subsequently Windows community has left its practical meaning as “the system codepage of whatever machine is being used”. The system codepage is also sometimes known as ‘mbcs’, since on East Asian systems that can be a multiple-byte-per-character encoding. Some code pages can even use top-bit-clear bytes as trailing bytes in a multibyte sequence, so it's not even strict compatible with plain ASCII... but even then, it's still called “ANSI”.

On US and Western European default settings, “ANSI” maps to Windows code page 1252. This is not the same as ISO-8859-1 (although it is quite similar). On other machines it could be anything else at all. This makes “ANSI” utterly useless as an external encoding identifier.

The application was unable to start correctly (0xc000007b)

Actually this error indicates to an invalid image format. However, why this is happening and what the error code usually means? Actually this could be appear when you are trying to run a program that is made for or intended to work with a 64 bit Windows operating system, but your computer is running on 32 bit Operating system.

Possible Reasons:

  • Microsoft Visual C++
  • Need to restart
  • DirectX
  • .NET Framework
  • Need to Re-Install
  • Need to Run the application as an administrator


What is the difference between UTF-8 and ISO-8859-1?


UTF is a family of multi-byte encoding schemes that can represent Unicode code points which can be representative of up to 2^31 [roughly 2 billion] characters. UTF-8 is a flexible encoding system that uses between 1 and 4 bytes to represent the first 2^21 [roughly 2 million] code points.

Long story short: any character with a code point/ordinal representation below 127, aka 7-bit-safe ASCII is represented by the same 1-byte sequence as most other single-byte encodings. Any character with a code point above 127 is represented by a sequence of two or more bytes, with the particulars of the encoding best explained here.


ISO-8859 is a family of single-byte encoding schemes used to represent alphabets that can be represented within the range of 127 to 255. These various alphabets are defined as "parts" in the format ISO-8859-n, the most familiar of these likely being ISO-8859-1 aka 'Latin-1'. As with UTF-8, 7-bit-safe ASCII remains unaffected regardless of the encoding family used.

The drawback to this encoding scheme is its inability to accommodate languages comprised of more than 128 symbols, or to safely display more than one family of symbols at one time. As well, ISO-8859 encodings have fallen out of favor with the rise of UTF. The ISO "Working Group" in charge of it having disbanded in 2004, leaving maintenance up to its parent subcommittee.

Unit testing with mockito for constructors

You can use PowerMockito

See the example:

Second second = Mockito.mock(Second.class);

But re-factoring is better decision.

C++ alignment when printing cout <<

The setw manipulator function will be of help here.

PHP write file from input to txt

Your form should look like this :

<form action="myprocessingscript.php" method="POST">
    <input name="field1" type="text" />
    <input name="field2" type="text" />
    <input type="submit" name="submit" value="Save Data">

and the PHP

if(isset($_POST['field1']) && isset($_POST['field2'])) {
    $data = $_POST['field1'] . '-' . $_POST['field2'] . "\r\n";
    $ret = file_put_contents('/tmp/mydata.txt', $data, FILE_APPEND | LOCK_EX);
    if($ret === false) {
        die('There was an error writing this file');
    else {
        echo "$ret bytes written to file";
else {
   die('no post data to process');

I wrote to /tmp/mydata.txt because this way I know exactly where it is. using data.txt writes to that file in the current working directory which I know nothing of in your example.

file_put_contents opens, writes and closes files for you. Don't mess with it.

Further reading: file_put_contents

Does Hibernate create tables in the database automatically

If property hibernate.ddl-auto = update, then it will not create the tables automatically. To create tables automatically, you need to set the property to hibernate.ddl-auto = create

The list of option which is used in the spring boot are

  • validate: validate the schema, makes no changes to the database.

  • update: update the schema.

  • create: creates the schema, destroying previous data.

  • create-drop: drop the schema at the end of the session

  • none: is all other cases

So for the first time you can set it to create and then next time on-wards you should set it to update.

PHP 7: Missing VCRUNTIME140.dll

Visual C++ Redistributable for Visual Studio 2015 (x32 bit version) - RC.

This should correct that. You can google for what the DLL is, but that's not important.

PS: It's officially from Microsoft too:)

Where I found it: Downloads (Visual Studio)

How do I use .toLocaleTimeString() without displaying seconds?

Simply convert the date to a string, and then concatenate the substrings you want out of it.

let time = date.toLocaleTimeString();
console.log(time.substr(0, 4) + time.substr(7, 3))
//=> 5:45 PM

Postgres integer arrays as parameters?

I realize this is an old question, but it took me several hours to find a good solution and thought I'd pass on what I learned here and save someone else the trouble. Try, for example,

SELECT * FROM some_table WHERE id_column = ANY(@id_list)

where @id_list is bound to an int[] parameter by way of

command.Parameters.Add("@id_list", NpgsqlDbType.Array | NpgsqlDbType.Integer).Value = my_id_list;

where command is a NpgsqlCommand (using C# and Npgsql in Visual Studio).

Is it possible to import modules from all files in a directory, using a wildcard?

I've used them a few times (in particular for building massive objects splitting the data over many files (e.g. AST nodes)), in order to build them I made a tiny script (which I've just added to npm so everyone else can use it).

Usage (currently you'll need to use babel to use the export file):

$ npm install -g folder-module
$ folder-module my-cool-module/

Generates a file containing:

export {default as foo} from "./module/foo.js"
export {default as default} from "./module/default.js"
export {default as bar} from "./module/bar.js"

Then you can just consume the file:

import * as myCoolModule from "my-cool-module.js"

Excel Calculate the date difference from today from a cell of "7/6/2012 10:26:42"

=ROUND((TODAY()-A1)/365,0) will provide number of years between date in cell A1 and today's date

How to break out of the IF statement

Try adding a control variable:

public void Method()
    bool doSomethingElse = true;
        //some code
            doSomethingElse = false;
        // The code i want to go if the second if is true

MySQL Update Column +1?

update post set count = count + 1 where id = 101

How do I create a unique ID in Java?

We can create a unique ID in java by using the UUID and call the method like randomUUID() on UUID.

String uniqueID = UUID.randomUUID().toString();

This will generate the random uniqueID whose return type will be String.

Why does the Google Play store say my Android app is incompatible with my own device?

To give an extra solution to the above 'This app is incompatible with your...' problem, let me share my solution for a different problem cause. I tried installing an app on a low-end Samsung Galaxy Y (GT-S6350) device and got this error from the Play store. To test various AndroidManifest configurations, I created an account and followed the routine as described in until my device showed up in the supported device list.

It turned out that a lot of devices become incompatible when you use the Camera permission:

<uses-permission android:name="android.permission.CAMERA" />

When I removed that specific permission, the application was available for 1180 devices instead of 870. Hope it will help someone

jQuery each loop in table row

In jQuery just use:

$('#tblOne > tbody  > tr').each(function() {...code...});

Using the children selector (>) you will walk over all the children (and not all descendents), example with three rows:

$('table > tbody  > tr').each(function(index, tr) { 



In VanillaJS you can use document.querySelectorAll() and walk over the rows using forEach()

[]'#tblOne > tbody  > tr'), function(index, tr) {
    /* console.log(index); */
    /* console.log(tr); */

How to properly compare two Integers in Java?

tl;dr my opinion is to use a unary + to trigger the unboxing on one of the operands when checking for value equality, and simply use the maths operators otherwise. Rationale follows:

It has been mentioned already that == comparison for Integer is identity comparison, which is usually not what a programmer want, and that the aim is to do value comparison; still, I've done a little science about how to do that comparison most efficiently, both in term of code compactness, correctness and speed.

I used the usual bunch of methods:

public boolean method1() {
    Integer i1 = 7, i2 = 5;
    return i1.equals( i2 );

public boolean method2() {
    Integer i1 = 7, i2 = 5;
    return i1.intValue() == i2.intValue();

public boolean method3() {
    Integer i1 = 7, i2 = 5;
    return i1.intValue() == i2;

public boolean method4() {
    Integer i1 = 7, i2 = 5;
    return i1 == +i2;

public boolean method5() { // obviously not what we want..
    Integer i1 = 7, i2 = 5;
    return i1 == i2;

and got this code after compilation and decompilation:

public boolean method1() {
    Integer var1 = Integer.valueOf( 7 );
    Integer var2 = Integer.valueOf( 5 );

    return var1.equals( var2 );

public boolean method2() {
    Integer var1 = Integer.valueOf( 7 );
    Integer var2 = Integer.valueOf( 5 );

    if ( var2.intValue() == var1.intValue() ) {
        return true;
    } else {
        return false;

public boolean method3() {
    Integer var1 = Integer.valueOf( 7 );
    Integer var2 = Integer.valueOf( 5 );

    if ( var2.intValue() == var1.intValue() ) {
        return true;
    } else {
        return false;

public boolean method4() {
    Integer var1 = Integer.valueOf( 7 );
    Integer var2 = Integer.valueOf( 5 );

    if ( var2.intValue() == var1.intValue() ) {
        return true;
    } else {
        return false;

public boolean method5() {
    Integer var1 = Integer.valueOf( 7 );
    Integer var2 = Integer.valueOf( 5 );

    if ( var2 == var1 ) {
        return true;
    } else {
        return false;

As you can easily see, method 1 calls Integer.equals() (obviously), methods 2-4 result in exactly the same code, unwrapping the values by means of .intValue() and then comparing them directly, and method 5 just triggers an identity comparison, being the incorrect way to compare values.

Since (as already mentioned by e.g. JS) equals() incurs an overhead (it has to do instanceof and an unchecked cast), methods 2-4 will work with exactly the same speed, noticingly better than method 1 when used in tight loops, since HotSpot is not likely to optimize out the casts & instanceof.

It's quite similar with other comparison operators (e.g. </>) - they will trigger unboxing, while using compareTo() won't - but this time, the operation is highly optimizable by HS since intValue() is just a getter method (prime candidate to being optimized out).

In my opinion, the seldom used version 4 is the most concise way - every seasoned C/Java developer knows that unary plus is in most cases equal to cast to int/.intValue() - while it may be a little WTF moment for some (mostly those who didn't use unary plus in their lifetime), it arguably shows the intent most clearly and most tersely - it shows that we want an int value of one of the operands, forcing the other value to unbox as well. It is also unarguably most similar to the regular i1 == i2 comparison used for primitive int values.

My vote goes for i1 == +i2 & i1 > i2 style for Integer objects, both for performance & consistency reasons. It also makes the code portable to primitives without changing anything other than the type declaration. Using named methods seems like introducing semantic noise to me, similar to the much-criticized bigInt.add(10).multiply(-3) style.

#1055 - Expression of SELECT list is not in GROUP BY clause and contains nonaggregated column this is incompatible with sql_mode=only_full_group_by

just go to the window bottom tray click on wamp icon ,click mysql->my.ini,then there is option ;sql-mode="" uncomment this make it like sql-mode="" and restart wamp worked for me

Facebook database design?

You're looking for foreign keys. Basically you can't have an array in a database unless it has it's own table.

Example schema:

    Users Table
        userID PK
        other data
    Friends Table
        userID   -- FK to users's table representing the user that has a friend.
        friendID -- FK to Users' table representing the user id of the friend

nginx error connect to php5-fpm.sock failed (13: Permission denied)

I just got this error again today as I updated my machine (with updates for PHP) running Ubuntu 14.04. The distribution config file /etc/php5/fpm/pool.d/www.conf is fine and doesn't require any changes currently.

I found the following errors:

dmesg | grep php
[ 4996.801789] traps: php5-fpm[23231] general protection ip:6c60d1 sp:7fff3f8c68f0 error:0 in php5-fpm[400000+800000]
[ 6788.335355] traps: php5-fpm[9069] general protection ip:6c5d81 sp:7fff98dd9a00 error:0 in php5-fpm[400000+7ff000]

The strange thing was that I have 2 sites running that utilize PHP-FPM on this machine one was running fine and the other (a Tiny Tiny RSS installation) gave me a 502, where both have been running fine before.

I compared both configuration files and found that fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; was missing for the affected site.

Both configuration files now contain the following block and are running fine again:

location ~ \.php$ {
        fastcgi_pass unix:/var/run/php5-fpm.sock;
        include /etc/nginx/snippets/fastcgi-php.conf;


It should be noted that Ubuntu ships two fastcgi related parameter files and also a configuration snippet which is available since Vivid and also in the PPA version. The solution was updated accordingly.

Diff of the fastcgi parameter files:

$ diff -up fastcgi_params fastcgi.conf
--- fastcgi_params      2015-07-22 01:42:39.000000000 +0200
+++ fastcgi.conf        2015-07-22 01:42:39.000000000 +0200
@@ -1,4 +1,5 @@

+fastcgi_param  SCRIPT_FILENAME    $document_root$fastcgi_script_name;
 fastcgi_param  QUERY_STRING       $query_string;
 fastcgi_param  REQUEST_METHOD     $request_method;
 fastcgi_param  CONTENT_TYPE       $content_type;

Configuration snippet in /etc/nginx/snippets/fastcgi-php.conf

# regex to split $uri to $fastcgi_script_name and $fastcgi_path
fastcgi_split_path_info ^(.+\.php)(/.+)$;

# Check that the PHP script exists before passing it
try_files $fastcgi_script_name =404;

# Bypass the fact that try_files resets $fastcgi_path_info
# see:
set $path_info $fastcgi_path_info;
fastcgi_param PATH_INFO $path_info;

fastcgi_index index.php;
include fastcgi.conf;

nodejs - first argument must be a string or Buffer - when using response.write with http.request

I get this error message and it mentions options.body

I had this originally{
    url: apiServerBaseUrl + '/v1/verify',
    body: {

I changed it to this:{
    url: apiServerBaseUrl + '/v1/verify',
    body: JSON.stringify({

and it seems to work now without the error message...seems like bug though.

I think this is the more official way to do it:{
        url: apiServerBaseUrl + '/v1/verify',
        json: true,
        body: {

Can't operator == be applied to generic types in C#?

" default == behaves as described above for both predefined and user-defined reference types."

Type T is not necessarily a reference type, so the compiler can't make that assumption.

However, this will compile because it is more explicit:

    bool Compare<T>(T x, T y) where T : class
        return x == y;

Follow up to additional question, "But, in case I'm using a reference type, would the the == operator use the predefined reference comparison, or would it use the overloaded version of the operator if a type defined one?"

I would have thought that == on the Generics would use the overloaded version, but the following test demonstrates otherwise. Interesting... I'd love to know why! If someone knows please share.

namespace TestProject
 class Program
    static void Main(string[] args)
        Test a = new Test();
        Test b = new Test();

        bool x = a == b;
        Compare<Test>(a, b);


    static bool Compare<T>(T x, T y) where T : class
        return x == y;

 class Test
    public static bool operator ==(Test a, Test b)
        Console.WriteLine("Overloaded == called");
        return a.Equals(b);

    public static bool operator !=(Test a, Test b)
        Console.WriteLine("Overloaded != called");
        return a.Equals(b);


Inline: Overloaded == called


Press any key to continue . . .

Follow Up 2

I do want to point out that changing my compare method to

    static bool Compare<T>(T x, T y) where T : Test
        return x == y;

causes the overloaded == operator to be called. I guess without specifying the type (as a where), the compiler can't infer that it should use the overloaded operator... though I'd think that it would have enough information to make that decision even without specifying the type.

MySQL Select Multiple VALUES

Try or:

WHERE id = 3 or id = 4

Or the equivalent in:

WHERE id in (3,4)

Java: using switch statement with enum under subclass

this should do:

//Main Class
public class SomeClass {

    public static class AnotherClass {
        public enum MyEnum {
            VALUE_A, VALUE_B
        public MyEnum myEnum;

    public void someMethod() { 
        AnotherClass.MyEnum enumExample = AnotherClass.MyEnum.VALUE_A; //...

        switch (enumExample) {
            case VALUE_A: { //<-- error on this line

window.close() doesn't work - Scripts may close only the windows that were opened by it

I searched for many pages of the web through of the Google and here on the Stack Overflow, but nothing suggested resolved my problem.

After many attempts, I've changed my way of to test that controller. Then I have discovered that the problem occurs always which I reopened the page through of the Ctrl + Shift + T shortcut in Chrome. So the page ran, but without a parent window reference, and because this can't be closed.

html 5 audio tag width

You also can set the width of a audio tag by JavaScript:

audio = document.getElementById('audio-id'); = '200px';

How do I call Objective-C code from Swift?

Just a note for whoever is trying to add an Objective-C library to Swift: You should add -ObjC in Build Settings -> Linking -> Other Linker Flags.

How do I remove the "extended attributes" on a file in Mac OS X?

Another recursive approach:

# change directory to target folder:
cd /Volumes/path/to/folder

# find all things of type "f" (file), 
# then pipe "|" each result as an argument (xargs -0) 
# to the "xattr -c" command:
find . -type f -print0 | xargs -0 xattr -c

# Sometimes you may have to use a star * instead of the dot.
# The dot just means "here" (whereever your cd'd to
find * -type f -print0 | xargs -0 xattr -c

How do I assert an Iterable contains elements with a certain property?

Its not especially Hamcrest, but I think it worth to mention here. What I use quite often in Java8 is something like:

assertTrue(myClass.getMyItems().stream().anyMatch(item -> "foo".equals(item.getName())));

(Edited to Rodrigo Manyari's slight improvement. It's a little less verbose. See comments.)

It may be a little bit harder to read, but I like the type and refactoring safety. Its also cool for testing multiple bean properties in combination. e.g. with a java-like && expression in the filter lambda.

How to edit .csproj file

Here is my option to Edit the project file without the need to Unload the project:

  1. Open Solution Explorer and switch to folder view: enter image description here

  2. Navigate to the Project which you want to edit inside the Solution folders and right-click on it.

  3. Choose Open from the Context Menu. enter image description here

That is it!

You will see the *.csproj file opened inside Visual Studio Editor.
After you can switch back to a Solution/Project view (see step 1).

enter image description here

How to solve Notice: Undefined index: id in C:\xampp\htdocs\invmgt\manufactured_goods\change.php on line 21

You are not getting value of $id=$_GET['id'];

And you are using it (before it gets initialised).

Use php's in built isset() function to check whether the variable is defied or not.

So, please update the line to:

$id = isset($_GET['id']) ? $_GET['id'] : '';

How can I override the OnBeforeUnload dialog and replace it with my own?

You can detect which button (ok or cancel) pressed by user, because the onunload function called only when the user choise leaveing the page. Althoug in this funcion the possibilities is limited, because the DOM is being collapsed. You can run javascript, but the ajax POST doesn't do anything therefore you can't use this methode for automatic logout. But there is a solution for that. The'logout.php') executed in the onunload funcion, so the user will logged out with a new window opening.

function onunload = (){'logout.php');

This code called when user leave the page or close the active window and user logged out by 'logout.php'. The new window close immediately when logout php consist of code:


Library not loaded: libmysqlclient.16.dylib error when trying to run 'rails server' on OS X 10.6 with mysql2 gem

Just ran into this problem. All I had to do is uninstall mysql2 gem and reinstall it. Hope this works for other people

Why does pycharm propose to change method to static

I agree with the answers given here (method does not use self and therefore could be decorated with @staticmethod).

I'd like to add that you maybe want to move the method to a top-level function instead of a static method inside a class. For details see this question and the accepted answer: python - should I use static methods or top-level functions

Moving the method to a top-level function will fix the PyCharm warning, too.