Programs & Examples On #Solution deployment

Invisible characters - ASCII

There is actually a truly invisible character: U+FEFF. This character is called the Byte Order Mark and is related to the Unicode 8 system. It is a really confusing concept that can be explained HERE The Byte Order Mark or BOM for short is an invisible character that doesn't take up any space. You can copy the character bellow between the > and <.

Here is the character:

> <

How to catch this character in action:

  • Copy the character between the > and <,
  • Write a line of text, then randomly put your caret in the line of text
  • Paste the character in the line.
  • Go to the beginning of the line and press and hold the right arrow key.

You will notice that when your caret gets to the place you pasted the character, it will briefly stop for around half a second. This is becuase the caret is passing over the invisible character. Even though you can't see it doesn't mean it isn't there. The caret still sees that there is a character in that area that you pasted the BOM and will pass through it. Since the BOM is invisble, the caret will look like it has paused for a brief moment. You can past the BOM multiple times in an area and redo the steps above to really show the affect. Good luck!

EDIT: Sadly, Stackoverflow doesn't like the character. Here is an example from

console.log showing contents of array object

It's simple to print an object to console in Javascript. Just use the following syntax:

console.log( object );


console.log('object: %O', object );

A relatively unknown method is following which prints an object or array to the console as table:

console.table( object );

I think it is important to say that this kind of logging statement only works inside a browser environment. I used this with Google Chrome. You can watch the output of your console.log calls inside the Developer Console: Open it by right click on any element in the webpage and select 'Inspect'. Select tab 'Console'.

Can I nest a <button> element inside an <a> using HTML5?

I've just jumped into the same issue and I solved it substituting 'button' tag to 'span' tag. In my case I'm using bootstrap. This is how it looks like:

<a href="#register"> 
    <span class="btn btn-default btn-lg">

Vue.js redirection to another page

if you want to route to another page this.$router.push({path: '/pagename'})

if you want to route with params this.$router.push({path: '/pagename', param: {param1: 'value1', param2: value2})

How can I get the behavior of GNU's readlink -f on a Mac?

Better late than never, I suppose. I was motivated to develop this specifically because my Fedora scripts weren't working on the Mac. The problem is dependencies and Bash. Macs don't have them, or if they do, they are often somewhere else (another path). Dependency path manipulation in a cross-platform Bash script is a headache at best and a security risk at worst - so it's best to avoid their use, if possible.

The function get_realpath() below is simple, Bash-centric, and no dependencies are required. I uses only the Bash builtins echo and cd. It is also fairly secure, as everything gets tested at each stage of the way and it returns error conditions.

If you don't want to follow symlinks, then put set -P at the front of the script, but otherwise cd should resolve the symlinks by default. It's been tested with file arguments that are {absolute | relative | symlink | local} and it returns the absolute path to the file. So far we've not had any problems with it.

function get_realpath() {

if [[ -f "$1" ]]
    # file *must* exist
    if cd "$(echo "${1%/*}")" &>/dev/null
        # file *may* not be local
        # exception is ./file.ext
        # try 'cd .; cd -;' *works!*
        local tmppwd="$PWD"
        cd - &>/dev/null
        # file *must* be local
        local tmppwd="$PWD"
    # file *cannot* exist
    return 1 # failure

# reassemble realpath
echo "$tmppwd"/"${1##*/}"
return 0 # success


You can combine this with other functions get_dirname, get_filename, get_stemname and validate_path. These can be found at our GitHub repository as realpath-lib (full disclosure - this is our product but we offer it free to the community without any restrictions). It also could serve as a instructional tool - it's well documented.

We've tried our best to apply so-called 'modern Bash' practices, but Bash is a big subject and I'm certain there will always be room for improvement. It requires Bash 4+ but could be made to work with older versions if they are still around.

Difference between a User and a Login in SQL Server

I think this is a very useful question with good answer. Just to add my two cents from the MSDN Create a Login page:

A login is a security principal, or an entity that can be authenticated by a secure system. Users need a login to connect to SQL Server. You can create a login based on a Windows principal (such as a domain user or a Windows domain group) or you can create a login that is not based on a Windows principal (such as an SQL Server login).

To use SQL Server Authentication, the Database Engine must use mixed mode authentication. For more information, see Choose an Authentication Mode.

As a security principal, permissions can be granted to logins. The scope of a login is the whole Database Engine. To connect to a specific database on the instance of SQL Server, a login must be mapped to a database user. Permissions inside the database are granted and denied to the database user, not the login. Permissions that have the scope of the whole instance of SQL Server (for example, the CREATE ENDPOINT permission) can be granted to a login.

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

While I think this compiler error is a good thing, there is a way you can work around it. Use a condition you know will be true:

public void myMethod(){


    if(1 < 2) return; // compiler isn't smart enough to complain about this



The compiler is not smart enough to complain about that.

curl error 18 - transfer closed with outstanding read data remaining

I had this problem working with pycurl and I solved it using

c.setopt(pycurl.HTTP_VERSION, pycurl.CURL_HTTP_VERSION_1_0) 

like Eric Caron says.

Need to navigate to a folder in command prompt

I prefer to use

pushd d:\windows\movie

because it requires no switches yet the working directory will change to the correct drive and path in one step.

Added plus:

  • also works with UNC paths if an unused drive letter is available for automatic drive mapping,
  • easy to go back to the previous working directory: just enter popd.

How can I copy a file from a remote server to using Putty in Windows?

It worked using PSCP. Instructions:

  1. Download PSCP.EXE from Putty download page
  2. Open command prompt and type set PATH=<path to the pscp.exe file>
  3. In command prompt point to the location of the pscp.exe using cd command
  4. Type pscp
  5. use the following command to copy file form remote server to the local system

    pscp [options] [user@]host:source target

So to copy the file /etc/hosts from the server as user fred to the file c:\temp\example-hosts.txt, you would type:

pscp [email protected]:/etc/hosts c:\temp\example-hosts.txt

How to add items into a numpy array

If x is just a single scalar value, you could try something like this to ensure the correct shape of the array that is being appended/concatenated to the rightmost column of a:

import numpy as np
a = np.array([[1,3,4],[1,2,3],[1,2,1]])
x = 10
b = np.hstack((a,x*np.ones((a.shape[0],1))))

returns b as:

array([[  1.,   3.,   4.,  10.],
       [  1.,   2.,   3.,  10.],
       [  1.,   2.,   1.,  10.]])

How to create module-wide variables in Python?

For this, you need to declare the variable as global. However, a global variable is also accessible from outside the module by using module_name.var_name. Add this as the first line of your module:

global __DBNAME__

How do I export a project in the Android studio?

1.- Export signed packages:

  • Use the Extract a Signed Android Application Package Wizard (On the main menu, choose Build | Generate Signed APK). The package will be signed during extraction.


  • Configure the .apk file as an artifact by creating an artifact definition of the type Android application with the Release signed package mode.

2.- Export unsigned packages: this can only be done through artifact definitions with the Debug or Release unsigned package mode specified.

Can Json.NET serialize / deserialize to / from a stream?

The current version of does not allow you to use the accepted answer code. A current alternative is:

public static object DeserializeFromStream(Stream stream)
    var serializer = new JsonSerializer();

    using (var sr = new StreamReader(stream))
    using (var jsonTextReader = new JsonTextReader(sr))
        return serializer.Deserialize(jsonTextReader);

Documentation: Deserialize JSON from a file stream

Get ASCII value at input word

char a='a';
char A='A';
System.out.println((int)a +" "+(int)A);

97 65

How to make a deep copy of Java ArrayList

public class Person{

    String s;
    Date d;

    public Person clone(){
        Person p = new Person();
        p.s = this.s.clone();
        p.d = this.d.clone();
        return p;

In your executing code:

ArrayList<Person> clone = new ArrayList<Person>();
for(Person p : originalList)

POST data with request module on Node.JS

If you're posting a json body, dont use the form parameter. Using form will make the arrays into field[0].attribute, field[1].attribute etc. Instead use body like so.

var jsonDataObj = {'mes': 'hey dude', 'yo': ['im here', 'and here']};{
    url: '',
    body: jsonDataObj,
    json: true
  }, function(error, response, body){

How to hide a div from code (c#)

if your div has the runat set to server, you surely can do a myDiv.Visible = false in your Page_PreRender event for example.

if you need help on using the session, have a look in msdn, it's very easy.

Delete the first three rows of a dataframe in pandas

A simple way is to use tail(-n) to remove the first n rows


Using margin / padding to space <span> from the rest of the <p>

Try in html:

style="display: inline-block; margin-top: 50px;"

or in css:

display: inline-block;
margin-top: 50px;

Adding a custom header to HTTP request using angular.js

my suggestion will be add a function call settings like this inside the function check the header which is appropriate for it. I am sure it will definitely work. it is perfectly working for me.

function getSettings(requestData) {
    return {
        url: requestData.url,
        dataType: requestData.dataType || "json",
        data: || {},
        headers: requestData.headers || {
            "accept": "application/json; charset=utf-8",
            'Authorization': 'Bearer ' + requestData.token
        async: requestData.async || "false",
        cache: requestData.cache || "false",
        success: requestData.success || {},
        error: requestData.error || {},
        complete: requestData.complete || {},
        fail: || {}

then call your data like this

    var requestData = {
        url: 'API end point',
        data: Your Request Data,
        token: Your Token

    var settings = getSettings(requestData);
    settings.method = "POST"; //("Your request type")
    return $http(settings);

How to replace comma (,) with a dot (.) using java

Use this:

String str = " 12,12"
str = str.replaceAll("(\\d+)\\,(\\d+)", "$1.$2");
System.out.println("str:"+str); //-> str:12.12

hope help you.

System not declared in scope?

Chances are that you've not included the header file that declares system().

In order to be able to compile C++ code that uses functions which you don't (manually) declare yourself, you have to pull in the declarations. These declarations are normally stored in so-called header files that you pull into the current translation unit using the #include preprocessor directive. As the code does not #include the header file in which system() is declared, the compilation fails.

To fix this issue, find out which header file provides you with the declaration of system() and include that. As mentioned in several other answers, you most likely want to add #include <cstdlib>

onClick function of an input type="button" not working

When I try:

<input type="button" id="moreFields" onclick="alert('The text will be show!!'); return false;" value="Give me more fields!"  />

It's worked well. So I think the problem is position of moreFields() function. Ensure that function will be define before your input tag.

Pls try:

<script type="text/javascript">
    function moreFields() {
        alert("The text will be show");

<input type="button" id="moreFields" onclick="moreFields()" value="Give me more fields!"  />

Hope it helped.

How to synchronize or lock upon variables in Java?

In this simple example you can just put synchronized as a modifier after public in both method signatures.

More complex scenarios require other stuff.

How can I start an Activity from a non-Activity class?

Your onTap override receives the MapView from which you can obtain the Context:

public boolean onTap(GeoPoint p, MapView mapView)
    // ...

    Intent intent = new Intent();
    intent.setClass(mapView.getContext(), FullscreenView.class);

    // ...

Inserting data to table (mysqli insert)

Okay, of course the question has been answered, but no-one seems to notice the third line of your code. It continuosly bugged me.

    mysql_select_db("web_table") or die(mysql_error());

for some reason, you made a mysqli connection to server, but you are trying to make a mysql connection to database.To get going, rather use

       $link = mysqli_connect("localhost","root","","web_table");
       mysqli_select_db ($link , "web_table" ) or die.....

or for where i began

     <?php $connection = mysqli_connect("localhost","root","","web_table");       
      global $connection; // global connection to databases - kill it once you're done

or just query with a $connection parameter as the other argument like above. Get rid of that third line.

how to change the dist-folder path in angular-cli after 'ng build'

The only thing that worked for me was to change outDir in in both angular-cli.json AND src/tsconfig.json.

I wanted my dist-folder outside the angular project folder. If I didn't change the setting in src/tsconfig.json as well, Angular CLI would throw warnings whenever I build the project.

Here are the most important lines ...

// angular-cli.json
  "apps": [
      "outDir": "../dist",

And ...

// tsconfig.json
  "compilerOptions": {
    "outDir": "../../dist/out-tsc",

Is it still valid to use IE=edge,chrome=1?

It's still valid to use IE=edge,chrome=1.

But, since the chrome frame project has been wound down the chrome=1 part is redundant for browsers that don't already have the chrome frame plug in installed.

I use the following for correctness nowadays

<meta http-equiv="X-UA-Compatible" content="IE=edge" />

How can I find out a file's MIME type (Content-Type)?

Try the file command with -i option.

-i option Causes the file command to output mime type strings rather than the more traditional human readable ones. Thus it may say text/plain; charset=us-ascii rather than ASCII text.

new Runnable() but no new thread?

Best and easy way is just pass argument and create instance and call thread method

Call thread using create a thread object and send a runnable class object with parameter or without parameter and start method of thread object.

In my condition I am sending parameter and I will use in run method.

new Thread(new FCMThreadController("2", null, "3", "1")).start();


new Thread(new FCMThreadController()).start();

public class FCMThreadController implements Runnable {
private String type;
private List<UserDeviceModel> devices;
private String message;
private String id;

    public FCMThreadController(String type, List<UserDeviceModel> devices, String message, String id) {

        this.type = type;
        this.devices = devices;
        this.message = message; = id;

    public FCMThreadController( ) {


    public void run() {
        // TODO Auto-generated method stub



Generate random numbers following a normal distribution in C/C++

There are many methods to generate Gaussian-distributed numbers from a regular RNG.

The Box-Muller transform is commonly used. It correctly produces values with a normal distribution. The math is easy. You generate two (uniform) random numbers, and by applying an formula to them, you get two normally distributed random numbers. Return one, and save the other for the next request for a random number.

Really killing a process in Windows

JosepStyons is right. Open cmd.exe and run

taskkill /im processname.exe /f

If there is an error saying,

ERROR: The process "process.exe" with PID 1234 could not be terminated. Reason: Access is denied.

then try running cmd.exe as administrator.

Removing App ID from Developer Connection

Does deleting the AppID do anything to disable versions of an Enterprise distributed app "in the wild" ??

If not, is there any way to kill off an Enterprise app before it's expiry?

How do I draw a grid onto a plot in Python?

To show a grid line on every tick, add


For example:

import matplotlib.pyplot as plt

points = [
    (0, 10),
    (10, 20),
    (20, 40),
    (60, 100),

x = list(map(lambda x: x[0], points))
y = list(map(lambda x: x[1], points))

plt.scatter(x, y)

enter image description here

In addition, you might want to customize the styling (e.g. solid line instead of dashed line), add:

plt.rc('grid', linestyle="-", color='black')

For example:

import matplotlib.pyplot as plt

points = [
    (0, 10),
    (10, 20),
    (20, 40),
    (60, 100),

x = list(map(lambda x: x[0], points))
y = list(map(lambda x: x[1], points))

plt.rc('grid', linestyle="-", color='black')
plt.scatter(x, y)

enter image description here

Message: Trying to access array offset on value of type null

This happens because $cOTLdata is not null but the index 'char_data' does not exist. Previous versions of PHP may have been less strict on such mistakes and silently swallowed the error / notice while 7.4 does not do this anymore.

To check whether the index exists or not you can use isset():


Which means the line should look something like this:

$len = isset($cOTLdata['char_data']) ? count($cOTLdata['char_data']) : 0;

Note I switched the then and else cases of the ternary operator since === null is essentially what isset already does (but in the positive case).

Simple Java Client/Server Program

you can get ip of that computer runs server program from DHCP list in that router you connected to.

How to compile without warnings being treated as errors?

Sure, find where -Werror is set and remove that flag. Then warnings will be only warnings.

How to prevent line-break in a column of a table cell (not a single cell)?

<table class="blueTable">
     <td>My name is good</td>
    table.blueTable td,
    table.blueTable th {
        white-space: nowrap;
        /* non-question related further styling */
        border: 1px solid #AAAAAA;
        padding: 3px 2px;
        text-align: left;

This is an example usage of the white space property with value nowrap, the bluetable is the class of the table, below the table are the CSS styles.

Use own username/password with git and bitbucket

Well, it's part of BitBucket philosophy and workflow:

  • Repository may have only one user: owner
  • For ordinary accounts (end-user's) collaboration expect "fork-pull request" workflow

i.e you can't (in usual case) commit into foreign repo under own credentials.

You have two possible solutions:

  1. "Classic" BB-way: fork repo (get owned by you repository), make changes, send pull request to origin repo
  2. Create "Team", add user-accounts as members of team, make Team owner of repository - it this case for this "Shared central" repository every team memeber can push under own credentials - inspect thg repository and TortoiseHg Team, owner of this repository, as samples

Error : getaddrinfo ENOTFOUND

Things to try:

  1. make sure you have internet connection: ping
  2. make sure you have DNS resolver working: ping
  3. make sure you can access ping
  4. make sure you can connect via https.

Try in your browser:

Make sure you are trying to connect to:


and not to:

  • ""

or some other weird string composed of few hostnames, because it's weird that the resolver complains about a hostnames that includes a port number, which it shouldn't care about. Ok, I tested and it should look like this for hosts that are not found.


From your comment to this answer it seems that you are not directly connected to the internet if you can't even ping

If you are using a proxy to access the Web, then you also have to configure npm to use it. Use:

npm config set proxy
npm config set https-proxy

but instead of use what you actually need in your company - ask someone or see how your browser is configured.

To see your proxy configuration in Chrome, see this.

Update 2

If you can access in your browser but you cannot run ping then it means that your browser must be configured to use a proxy, or other programs than your browser must be restricted from using the internet.

In any case, you should ask someone in your company about it because most likely you either need to use a specific proxy or someone needs to lift the restriction from your npm and allow it to access the network.

The network access can be blocked by a firewall installed on your computer or a router in your network. It's hard to say without knowing the specific configuration in your company.

Update 3

Remove the environment variable "https_proxy" if any or use correct value for "https_proxy"

Specify path to node_modules in package.json

yes you can, just set the NODE_PATH env variable :

export NODE_PATH='yourdir'/node_modules

According to the doc :

If the NODE_PATH environment variable is set to a colon-delimited list of absolute paths, then node will search those paths for modules if they are not found elsewhere. (Note: On Windows, NODE_PATH is delimited by semicolons instead of colons.)

Additionally, node will search in the following locations:

1: $HOME/.node_modules

2: $HOME/.node_libraries

3: $PREFIX/lib/node

Where $HOME is the user's home directory, and $PREFIX is node's configured node_prefix.

These are mostly for historic reasons. You are highly encouraged to place your dependencies locally in node_modules folders. They will be loaded faster, and more reliably.


React js change child component's state from parent component

The parent component can manage child state passing a prop to child and the child convert this prop in state using componentWillReceiveProps.

class ParentComponent extends Component {
  state = { drawerOpen: false }
  toggleChildMenu = () => {
    this.setState({ drawerOpen: !this.state.drawerOpen })
  render() {
    return (
        <button onClick={this.toggleChildMenu}>Toggle Menu from Parent</button>
        <ChildComponent drawerOpen={this.state.drawerOpen} />

class ChildComponent extends Component {
  constructor(props) {
    this.state = {
      open: false

  componentWillReceiveProps(props) {
    this.setState({ open: props.drawerOpen })

  toggleMenu() {
      open: !

  render() {
    return <Drawer open={} />

An existing connection was forcibly closed by the remote host

Had the same bug. Actually worked in case the traffic was sent using some proxy (fiddler in my case). Updated .NET framework from 4.5.2 to >=4.6 and now everything works fine. The actual request was:
new WebClient().DownloadData("URL");
The exception was:

SocketException: An existing connection was forcibly closed by the remote host

How to round a numpy array?

If you want the output to be

array([1.6e-01, 9.9e-01, 3.6e-04])

the problem is not really a missing feature of NumPy, but rather that this sort of rounding is not a standard thing to do. You can make your own rounding function which achieves this like so:

def my_round(value, N):
    exponent = np.ceil(np.log10(value))
    return 10**exponent*np.round(value*10**(-exponent), N)

For a general solution handling 0 and negative values as well, you can do something like this:

def my_round(value, N):
    value = np.asarray(value).copy()
    zero_mask = (value == 0)
    value[zero_mask] = 1.0
    sign_mask = (value < 0)
    value[sign_mask] *= -1
    exponent = np.ceil(np.log10(value))
    result = 10**exponent*np.round(value*10**(-exponent), N)
    result[sign_mask] *= -1
    result[zero_mask] = 0.0
    return result

Why does printf not flush after the call unless a newline is in the format string?

There are generally 2 levels of buffering-

1. Kernel buffer Cache (makes read/write faster)

2. Buffering in I/O library (reduces no. of system calls)

Let's take example of fprintf and write().

When you call fprintf(), it doesn't wirte directly to the file. It first goes to stdio buffer in the program's memory. From there it is written to the kernel buffer cache by using write system call. So one way to skip I/O buffer is directly using write(). Other ways are by using setbuff(stream,NULL). This sets the buffering mode to no buffering and data is directly written to kernel buffer. To forcefully make the data to be shifted to kernel buffer, we can use "\n", which in case of default buffering mode of 'line buffering', will flush I/O buffer. Or we can use fflush(FILE *stream).

Now we are in kernel buffer. Kernel(/OS) wants to minimise disk access time and hence it reads/writes only blocks of disk. So when a read() is issued, which is a system call and can be invoked directly or through fscanf(), kernel reads the disk block from disk and stores it in a buffer. After that data is copied from here to user space.

Similarly that fprintf() data recieved from I/O buffer is written to the disk by the kernel. This makes read() write() faster.

Now to force the kernel to initiate a write(), after which data transfer is controlled by hardware controllers, there are also some ways. We can use O_SYNC or similar flags during write calls. Or we could use other functions like fsync(),fdatasync(),sync() to make the kernel initiate writes as soon as data is available in the kernel buffer.

how to set imageview src?

What you are looking for is probably this:

ImageView myImageView;
myImageView = mDialog.findViewById(;
String src = "imageFileName"

int drawableId = this.getResources().getIdentifier(src, "drawable", context.getPackageName())

Let me know if this was helpful :)

Converting a PDF to PNG

As this page also lists alternative tools I'll mention xpdf which has command line tools ready compiled for Linux/Windows/Mac. Supports transparency. Is free for commercial use - opposed to Ghostscript which has truly outrageous pricing.

In a test on a huge PDF file it was 7.5% faster than Ghostscript.

(It also has PDF to text and HTML converters)

What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?

I suggest you do some experiments using "make". Here is a simple demo, showing the difference between = and :=.

/* Filename: Makefile*/
x := foo
y := $(x) bar
x := later

a = foo
b = $(a) bar
a = later

    @echo x - $(x)
    @echo y - $(y)
    @echo a - $(a)
    @echo b - $(b)

make test prints:

x - later
y - foo bar
a - later
b - later bar

Check more elaborate explanation here

jQuery append() - return appended elements

var newElementsAppended = $(newHtml).appendTo("#myDiv");
newElementsAppended.effects("highlight", {}, 2000);

Format / Suppress Scientific Notation from Python Pandas Aggregation Results

I had multiple dataframes with different floating point, so thx to Allans idea made dynamic length.

pd.set_option('display.float_format', lambda x: f'%.{len(str(x%1))-2}f' % x)

The minus of this is that if You have last 0 in float, it will cut it. So it will be not 0.000070, but 0.00007. Connection refused

In my case, I gave the socket the name of the server (in my case "raspberrypi"), and instead an IPv4 address made it, or to specify, IPv6 was broken (the name resolved to an IPv6)

How to change TextBox's Background color?

Setting textbox backgroundcolor with multiple colors on single click.

Note:- using HTML and Javscript.

< input id="ClickMe_btn" onclick="setInterval(function () { ab() }, 3000);" type="button" value="ClickMe" />

var arr, i = 0; arr = ["Red", "Blue", "Green", " Orange ", "Purple", "Yellow", "Brown", "Lime", "Grey"]; // We provide array as input.

    function ab()
     {   document.getElementById("Text").style.backgroundColor = arr[i];

Note: You can change milliseconds, with setInterval 2nd parameter.

Equivalent of Super Keyword in C#

C# equivalent of your code is

  class Imagedata : PDFStreamEngine
     // C# uses "base" keyword whenever Java uses "super" 
     // so instead of super(...) in Java we should call its C# equivalent (base):
     public Imagedata()
       : base(ResourceLoader.loadProperties("org/apache/pdfbox/resources/", true)) 
     { }

     // Java methods are virtual by default, when C# methods aren't.
     // So we should be sure that processOperator method in base class 
     // (that is PDFStreamEngine)
     // declared as "virtual"
     protected override void processOperator(PDFOperator operations, List arguments)
        base.processOperator(operations, arguments);

React Native absolute positioning horizontal centre

create a full-width View with alignItems: "center" then insert desired children inside.

import React from "react";
import {View} from "react-native";

export default class AbsoluteComponent extends React.Component {
     <View style={{position: "absolute", left: 0, right: 0, alignItems: "center"}}>

you can add properties like bottom: 30 for bottom aligned component.

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

I've encountered similar problems. The reason is that the path to my eclipse includes Chinese characters. Once those characters are deleted, the problem is solved. Please check if there are characters other than English in your path.

How to include a quote in a raw Python string

Nevermind, the answer is raw triple-quoted strings:


SASS - use variables across multiple files

In angular v10 I did something like this, first created a master.scss file and included the following variables:

master.scss file:

$theme: blue;

$button_color: red;

$label_color: gray;

Then I imported the master.scss file in my style.scss at the top:

style.scss file:

@use './master' as m;

Make sure you import the master.scss at the top.

m is an alias for the namespace;

Use @use instead of @import according to the official docs below:

Then in your styles.scss file you can use any variable which is defined in master.scss like below:

someClass {

   backgroud-color: m.$theme;

   color: m.$button_color;


Hope it 'll help...

Happy Coding :)

SQL Server : Columns to Rows

I needed a solution to convert columns to rows in Microsoft SQL Server, without knowing the colum names (used in trigger) and without dynamic sql (dynamic sql is too slow for use in a trigger).

I finally found this solution, which works fine:

    attr.insRow.value('local-name(.)', 'nvarchar(128)') as FieldName,
    attr.insRow.value('.', 'nvarchar(max)') as FieldValue 
FROM ( Select      
          i.ID as PK,
          i.LastModifiedBy as Username,
          convert(xml, (select i.* for xml raw)) as insRowCol
       FROM inserted as i
     ) as insRowTbl
CROSS APPLY insRowTbl.insRowCol.nodes('/row/@*') as attr(insRow)

As you can see, I convert the row into XML (Subquery select i,* for xml raw, this converts all columns into one xml column)

Then I CROSS APPLY a function to each XML attribute of this column, so that I get one row per attribute.

Overall, this converts columns into rows, without knowing the column names and without using dynamic sql. It is fast enough for my purpose.

(Edit: I just saw Roman Pekar answer above, who is doing the same. I used the dynamic sql trigger with cursors first, which was 10 to 100 times slower than this solution, but maybe it was caused by the cursor, not by the dynamic sql. Anyway, this solution is very simple an universal, so its definitively an option).

I am leaving this comment at this place, because I want to reference this explanation in my post about the full audit trigger, that you can find here:

Push an associative item into an array in JavaScript

JavaScript has associative arrays.

Here is a working snippet.

<script type="text/javascript">
  var myArray = [];
  myArray['thank'] = 'you';
  myArray['no'] = 'problem';

They are simply called objects.

How to manually set an authenticated user in Spring Security / SpringMVC

I couldn't find any other full solutions so I thought I would post mine. This may be a bit of a hack, but it resolved the issue to the above problem:

public void login(HttpServletRequest request, String userName, String password)

    UsernamePasswordAuthenticationToken authRequest = new UsernamePasswordAuthenticationToken(userName, password);

    // Authenticate the user
    Authentication authentication = authenticationManager.authenticate(authRequest);
    SecurityContext securityContext = SecurityContextHolder.getContext();

    // Create a new session and add the security context.
    HttpSession session = request.getSession(true);
    session.setAttribute("SPRING_SECURITY_CONTEXT", securityContext);

getResources().getColor() is deprecated

I found that the useful getResources().getColor(R.color.color_name) is deprecated.

It is not deprecated in API Level 21, according to the documentation.

It is deprecated in the M Developer Preview. However, the replacement method (a two-parameter getColor() that takes the color resource ID and a Resources.Theme object) is only available in the M Developer Preview.

Hence, right now, continue using the single-parameter getColor() method. Later this year, consider using the two-parameter getColor() method on Android M devices, falling back to the deprecated single-parameter getColor() method on older devices.

Replace Div with another Div

This should help you


<!-- pretty much i just need to click a link within the regions table and it changes to the neccesary div. -->

<tr class="thumb"></tr>
    <td><a href="#" class="showall">All Regions</a> (shows main map) (link)</td>   

<tr class="thumb"></tr>
<td>Northern Region (link)</td>

<tr class="thumb"></tr>
<td>Southern Region (link)</td>

<tr class="thumb"></tr>
<td>Eastern Region (link)</td>
<br />

<div id="mainmapplace">
    <div id="mainmap">
        All Regions image
<div id="region">
    <div class="replace">northern image</div>
    <div class="replace">southern image</div>
    <div class="replace">Eastern image</div>


var originalmap;
var flag = false;

$(function (){

            flag = true;
            originalmap = $('#mainmap');

            if(flag == true){
                $('#region').append($('#mainmapplace .replace'));                



    width: 100px;
    height: 100px;
    background: red;

#region div{
    width: 100px;
    height: 100px;
    background: blue;
    margin: 10px 0 0 0;

How can I rollback an UPDATE query in SQL server 2005?

begin transaction

// execute SQL code here

rollback transaction

If you've already executed the query and want to roll it back, unfortunately your only real option is to restore a database backup. If you're using Full backups, then you should be able to restore the database to a specific point in time.

Returning first x items from array

If you just want to output the first 5 elements, you should write something like:


  if (!empty ( $an_array ) ) {

    $min = min ( count ( $an_array ), 5 );

    $i = 0;

    foreach ($value in $an_array) {

      echo $value;
      if ($i == $min) break;




If you want to write a function which returns part of the array, you should use array_slice:


  function GetElements( $an_array, $elements ) {
    return array_slice( $an_array, 0, $elements );


Using Jquery AJAX function with datatype HTML

Here is a version that uses dataType html, but this is far less explicit, because i am returning an empty string to indicate an error.

Ajax call:

  type : 'POST',
  url : 'post.php',
  dataType : 'html',
  data: {
      email : $('#email').val()
  success : function(data){
      $('#message').removeClass().addClass((data == '') ? 'error' : 'success')
      if (data == '') {
          $('#message').html("Format your email correcly");
  error : function(XMLHttpRequest, textStatus, errorThrown) {
      .text('There was an error.').show(500);




function processEmail($email) {
    if (preg_match("#^[a-zA-Z0-9_.-]+@[a-zA-Z0-9-]+.[a-zA-Z0-9-.]+$#", $email)) {
        // your logic here (ex: add into database)
        return true;
    return false;

if (processEmail($_POST['email'])) {
    echo "<span>Your email is <strong>{$_POST['email']}</strong></span>";

matplotlib: Group boxplots

Here's a function I wrote that takes Molly's code and some other code I've found on the internet to make slightly fancier grouped boxplots:

import numpy as np
import matplotlib.pyplot as plt

def custom_legend(colors, labels, linestyles=None):
    """ Creates a list of matplotlib Patch objects that can be passed to the legend(...) function to create a custom

    :param colors: A list of colors, one for each entry in the legend. You can also include a linestyle, for example: 'k--'
    :param labels:  A list of labels, one for each entry in the legend.

    if linestyles is not None:
        assert len(linestyles) == len(colors), "Length of linestyles must match length of colors."

    h = list()
    for k,(c,l) in enumerate(zip(colors, labels)):
        clr = c
        ls = 'solid'
        if linestyles is not None:
            ls = linestyles[k]
        patch = patches.Patch(color=clr, label=l, linestyle=ls)
    return h

def grouped_boxplot(data, group_names=None, subgroup_names=None, ax=None, subgroup_colors=None,
                    box_width=0.6, box_spacing=1.0):
    """ Draws a grouped boxplot. The data should be organized in a hierarchy, where there are multiple
        subgroups for each main group.

    :param data: A dictionary of length equal to the number of the groups. The key should be the
                group name, the value should be a list of arrays. The length of the list should be
                equal to the number of subgroups.
    :param group_names: (Optional) The group names, should be the same as data.keys(), but can be ordered.
    :param subgroup_names: (Optional) Names of the subgroups.
    :param subgroup_colors: A list specifying the plot color for each subgroup.
    :param ax: (Optional) The axis to plot on.

    if group_names is None:
        group_names = data.keys()

    if ax is None:
        ax = plt.gca()

    nsubgroups = np.array([len(v) for v in data.values()])
    assert len(np.unique(nsubgroups)) == 1, "Number of subgroups for each property differ!"
    nsubgroups = nsubgroups[0]

    if subgroup_colors is None:
        subgroup_colors = list()
        for k in range(nsubgroups):
        assert len(subgroup_colors) == nsubgroups, "subgroup_colors length must match number of subgroups (%d)" % nsubgroups

    def _decorate_box(_bp, _d):
        plt.setp(_bp['boxes'], lw=0, color='k')
        plt.setp(_bp['whiskers'], lw=3.0, color='k')

        # fill in each box with a color
        assert len(_bp['boxes']) == nsubgroups
        for _k,_box in enumerate(_bp['boxes']):
            _boxX = list()
            _boxY = list()
            for _j in range(5):
            _boxCoords = zip(_boxX, _boxY)
            _boxPolygon = plt.Polygon(_boxCoords, facecolor=subgroup_colors[_k])

        # draw a black line for the median
        for _k,_med in enumerate(_bp['medians']):
            _medianX = list()
            _medianY = list()
            for _j in range(2):
                plt.plot(_medianX, _medianY, 'k', linewidth=3.0)

            # draw a black asterisk for the mean
            plt.plot([np.mean(_med.get_xdata())], [np.mean(_d[_k])], color='w', marker='*',
                      markeredgecolor='k', markersize=12)

    cpos = 1
    label_pos = list()
    for k in group_names:
        d = data[k]
        nsubgroups = len(d)
        pos = np.arange(nsubgroups) + cpos
        bp = plt.boxplot(d, positions=pos, widths=box_width)
        _decorate_box(bp, d)
        cpos += nsubgroups + box_spacing

    plt.xlim(0, cpos-1)
    plt.xticks(label_pos, group_names)

    if subgroup_names is not None:
        leg = custom_legend(subgroup_colors, subgroup_names)

You can use the function(s) like this:

data = { 'A':[np.random.randn(100), np.random.randn(100) + 5],
         'B':[np.random.randn(100)+1, np.random.randn(100) + 9],
         'C':[np.random.randn(100)-3, np.random.randn(100) -5]

grouped_boxplot(data, group_names=['A', 'B', 'C'], subgroup_names=['Apples', 'Oranges'], subgroup_colors=['#D02D2E', '#D67700'])

php: how to get associative array key from numeric index?

$array = array( 'one' =>'value', 'two' => 'value2' );

$allKeys = array_keys($array);
echo $allKeys[0];

Which will output:


How do you format a Date/Time in TypeScript?

I had a similar problem and I solved with this


Div with margin-left and width:100% overflowing on the right side

If some other portion of your layout is influencing the div width you can set width:auto and the div (which is a block element) will fill the space

<div style="width:auto">
    <div style="margin-left:45px;width:auto">
        <asp:TextBox ID="txtTitle" runat="server" Width="100%"></asp:TextBox><br />

If that's still not working we may need to see more of your layout HTML/CSS

Using IQueryable with Linq

Although Reed Copsey and Marc Gravell already described about IQueryable (and also IEnumerable) enough,mI want to add little more here by providing a small example on IQueryable and IEnumerable as many users asked for it

Example: I have created two table in database

   CREATE TABLE [dbo].[Employee]([PersonId] [int] NOT NULL PRIMARY KEY,[Gender] [nchar](1) NOT NULL)
   CREATE TABLE [dbo].[Person]([PersonId] [int] NOT NULL PRIMARY KEY,[FirstName] [nvarchar](50) NOT NULL,[LastName] [nvarchar](50) NOT NULL)

The Primary key(PersonId) of table Employee is also a forgein key(personid) of table Person

Next i added entity model in my application and create below service class on that

public class SomeServiceClass
    public IQueryable<Employee> GetEmployeeAndPersonDetailIQueryable(IEnumerable<int> employeesToCollect)
        DemoIQueryableEntities db = new DemoIQueryableEntities();
        var allDetails = from Employee e in db.Employees
                         join Person p in db.People on e.PersonId equals p.PersonId
                         where employeesToCollect.Contains(e.PersonId)
                         select e;
        return allDetails;

    public IEnumerable<Employee> GetEmployeeAndPersonDetailIEnumerable(IEnumerable<int> employeesToCollect)
        DemoIQueryableEntities db = new DemoIQueryableEntities();
        var allDetails = from Employee e in db.Employees
                         join Person p in db.People on e.PersonId equals p.PersonId
                         where employeesToCollect.Contains(e.PersonId)
                         select e;
        return allDetails;

they contains same linq. It called in program.cs as defined below

class Program
    static void Main(string[] args)
        SomeServiceClass s= new SomeServiceClass(); 

        var employeesToCollect= new []{0,1,2,3};

        //IQueryable execution part
        var IQueryableList = s.GetEmployeeAndPersonDetailIQueryable(employeesToCollect).Where(i => i.Gender=="M");            
        foreach (var emp in IQueryableList)
            System.Console.WriteLine("ID:{0}, EName:{1},Gender:{2}", emp.PersonId, emp.Person.FirstName, emp.Gender);
        System.Console.WriteLine("IQueryable contain {0} row in result set", IQueryableList.Count());

        //IEnumerable execution part
        var IEnumerableList = s.GetEmployeeAndPersonDetailIEnumerable(employeesToCollect).Where(i => i.Gender == "M");
        foreach (var emp in IEnumerableList)
           System.Console.WriteLine("ID:{0}, EName:{1},Gender:{2}", emp.PersonId, emp.Person.FirstName, emp.Gender);
        System.Console.WriteLine("IEnumerable contain {0} row in result set", IEnumerableList.Count());


The output is same for both obviously

ID:1, EName:Ken,Gender:M  
ID:3, EName:Roberto,Gender:M  
IQueryable contain 2 row in result set  
ID:1, EName:Ken,Gender:M  
ID:3, EName:Roberto,Gender:M  
IEnumerable contain 2 row in result set

So the question is what/where is the difference? It does not seem to have any difference right? Really!!

Let's have a look on sql queries generated and executed by entity framwork 5 during these period

IQueryable execution part

[Extent1].[PersonId] AS [PersonId], 
[Extent1].[Gender] AS [Gender]
FROM [dbo].[Employee] AS [Extent1]
WHERE ([Extent1].[PersonId] IN (0,1,2,3)) AND (N'M' = [Extent1].[Gender])

[GroupBy1].[A1] AS [C1]
    COUNT(1) AS [A1]
    FROM [dbo].[Employee] AS [Extent1]
    WHERE ([Extent1].[PersonId] IN (0,1,2,3)) AND (N'M' = [Extent1].[Gender])
)  AS [GroupBy1]

IEnumerable execution part

[Extent1].[PersonId] AS [PersonId], 
[Extent1].[Gender] AS [Gender]
FROM [dbo].[Employee] AS [Extent1]
WHERE [Extent1].[PersonId] IN (0,1,2,3)

[Extent1].[PersonId] AS [PersonId], 
[Extent1].[Gender] AS [Gender]
FROM [dbo].[Employee] AS [Extent1]
WHERE [Extent1].[PersonId] IN (0,1,2,3)

Common script for both execution part

/* these two query will execute for both IQueryable or IEnumerable to get details from Person table
   Ignore these two queries here because it has nothing to do with IQueryable vs IEnumerable
exec sp_executesql N'SELECT 
[Extent1].[PersonId] AS [PersonId], 
[Extent1].[FirstName] AS [FirstName], 
[Extent1].[LastName] AS [LastName]
FROM [dbo].[Person] AS [Extent1]
WHERE [Extent1].[PersonId] = @EntityKeyValue1',N'@EntityKeyValue1 int',@EntityKeyValue1=1

exec sp_executesql N'SELECT 
[Extent1].[PersonId] AS [PersonId], 
[Extent1].[FirstName] AS [FirstName], 
[Extent1].[LastName] AS [LastName]
FROM [dbo].[Person] AS [Extent1]
WHERE [Extent1].[PersonId] = @EntityKeyValue1',N'@EntityKeyValue1 int',@EntityKeyValue1=3

So you have few questions now, let me guess those and try to answer them

Why are different scripts generated for same result?

Lets find out some points here,

all queries has one common part

WHERE [Extent1].[PersonId] IN (0,1,2,3)

why? Because both function IQueryable<Employee> GetEmployeeAndPersonDetailIQueryable and IEnumerable<Employee> GetEmployeeAndPersonDetailIEnumerable of SomeServiceClass contains one common line in linq queries

where employeesToCollect.Contains(e.PersonId)

Than why is the AND (N'M' = [Extent1].[Gender]) part is missing in IEnumerable execution part, while in both function calling we used Where(i => i.Gender == "M") inprogram.cs`

Now we are in the point where difference came between IQueryable and IEnumerable

What entity framwork does when an IQueryable method called, it tooks linq statement written inside the method and try to find out if more linq expressions are defined on the resultset, it then gathers all linq queries defined until the result need to fetch and constructs more appropriate sql query to execute.

It provide a lots of benefits like,

  • only those rows populated by sql server which could be valid by the whole linq query execution
  • helps sql server performance by not selecting unnecessary rows
  • network cost get reduce

like here in example sql server returned to application only two rows after IQueryable execution` but returned THREE rows for IEnumerable query why?

In case of IEnumerable method, entity framework took linq statement written inside the method and constructs sql query when result need to fetch. it does not include rest linq part to constructs the sql query. Like here no filtering is done in sql server on column gender.

But the outputs are same? Because 'IEnumerable filters the result further in application level after retrieving result from sql server

SO, what should someone choose? I personally prefer to define function result as IQueryable<T> because there are lots of benefit it has over IEnumerable like, you could join two or more IQueryable functions, which generate more specific script to sql server.

Here in example you can see an IQueryable Query(IQueryableQuery2) generates a more specific script than IEnumerable query(IEnumerableQuery2) which is much more acceptable in my point of view.

How to parse json string in Android?

Below is the link which guide in parsing JSON string in android.

Also according to your json string code snippet must be something like this:-

JSONObject mainObject = new JSONObject(yourstring);

JSONObject universityObject = mainObject.getJSONObject("university");
JSONString name = universityObject.getString("name");  
JSONString url = universityObject.getString("url");

Following is the API reference for JSOnObject:

Same for other object.

Merge Two Lists in R

Here are two options, the first:

both <- list(first, second)
n <- unique(unlist(lapply(both, names)))
names(n) <- n
lapply(n, function(ni) unlist(lapply(both, `[[`, ni)))

and the second, which works only if they have the same structure:

apply(cbind(first, second),1,function(x) unname(unlist(x)))

Both give the desired result.

How to evaluate a math expression given in string form?

import java.util.*;

public class check { 
   int ans;
   String str="7 + 5";
   StringTokenizer st=new StringTokenizer(str);

   int v1=Integer.parseInt(st.nextToken());
   String op=st.nextToken();
   int v2=Integer.parseInt(st.nextToken());

   if(op.equals("+")) { ans= v1 + v2; }
   if(op.equals("-")) { ans= v1 - v2; }

String replacement in java, similar to a velocity template

There is nothing out of the box that is comparable to velocity since velocity was written to solve exactly that problem. The closest thing you can try is looking into the Formatter

However the formatter as far as I know was created to provide C like formatting options in Java so it may not scratch exactly your itch but you are welcome to try :).

Exponentiation in Python - should I prefer ** operator instead of math.pow and math.sqrt?

math.sqrt is the C implementation of square root and is therefore different from using the ** operator which implements Python's built-in pow function. Thus, using math.sqrt actually gives a different answer than using the ** operator and there is indeed a computational reason to prefer numpy or math module implementation over the built-in. Specifically the sqrt functions are probably implemented in the most efficient way possible whereas ** operates over a large number of bases and exponents and is probably unoptimized for the specific case of square root. On the other hand, the built-in pow function handles a few extra cases like "complex numbers, unbounded integer powers, and modular exponentiation".

See this Stack Overflow question for more information on the difference between ** and math.sqrt.

In terms of which is more "Pythonic", I think we need to discuss the very definition of that word. From the official Python glossary, it states that a piece of code or idea is Pythonic if it "closely follows the most common idioms of the Python language, rather than implementing code using concepts common to other languages." In every single other language I can think of, there is some math module with basic square root functions. However there are languages that lack a power operator like ** e.g. C++. So ** is probably more Pythonic, but whether or not it's objectively better depends on the use case.

sending mail from Batch file

You can also use a Power Shell script:

$smtp = new-object Net.Mail.SmtpClient("")

if( $Env:SmtpUseCredentials -eq "true" ) {
    $credentials = new-object Net.NetworkCredential("username","password")
    $smtp.Credentials = $credentials
$objMailMessage = New-Object System.Net.Mail.MailMessage
$objMailMessage.From = "[email protected]"
$objMailMessage.To.Add("[email protected]")
$objMailMessage.Subject = "eMail subject Notification"
$objMailMessage.Body = "Hello world!"


C++, How to determine if a Windows Process is running?

You can never check and see if a process is running, you can only check to see if a process was running at some point in the recent past. A process is an entity that is not controlled by your application and can exit at any moment in time. There is no way to guaranteed that a process will not exit in between the check to see if it's running and the corresponding action.

The best approach is to just do the action required and catch the exception that would be thrown if the process was not running.

dropping infinite values from dataframes in pandas?

The above solution will modify the infs that are not in the target columns. To remedy that,

lst = [np.inf, -np.inf]
to_replace = {v: lst for v in ['col1', 'col2']}
df.replace(to_replace, np.nan)

Bootstrap 3 modal responsive

I had the same problem, and a easy way i found to solve that was to make everything in the modal's body responsive(using boostrap classes) and my problem were solved.

error C4996: 'scanf': This function or variable may be unsafe in c programming

It sounds like it's just a compiler warning.

Usage of scanf_s prevents possible buffer overflow.

Good explanation as to why scanf can be dangerous: Disadvantages of scanf

So as suggested, you can try replacing scanf with scanf_s or disable the compiler warning.

How to assign the output of a command to a Makefile variable

Use the Make shell builtin like in MY_VAR=$(shell echo whatever)

MY_VAR IS whatever

me@Zack:~$ cat Makefile 
MY_VAR := $(shell echo whatever)

    @echo MY_VAR IS $(MY_VAR)

How to change current Theme at runtime in Android

recreate() (as mentioned by TPReal) will only restart current activity, but the previous activities will still be in back stack and theme will not be applied to them.

So, another solution for this problem is to recreate the task stack completely, like this:

            .addNextIntent(new Intent(getActivity(), MainActivity.class))


Just put the code above after you perform changing of theme on the UI or somewhere else. All your activities should have method setTheme() called before onCreate(), probably in some parent activity. It is also a normal approach to store the theme chosen in SharedPreferences, read it and then set using setTheme() method.

PHP - concatenate or directly insert variables in string

I prefer this all the time and found it much easier.

echo "Welcome {$name}!"

How to calculate the number of days between two dates?

Here's what I use. If you just subtract the dates, it won't work across the Daylight Savings Time Boundary (eg April 1 to April 30 or Oct 1 to Oct 31). This drops all the hours to make sure you get a day and eliminates any DST problem by using UTC.

var nDays = (    Date.UTC(EndDate.getFullYear(), EndDate.getMonth(), EndDate.getDate()) -
                 Date.UTC(StartDate.getFullYear(), StartDate.getMonth(), StartDate.getDate())) / 86400000;

as a function:

function DaysBetween(StartDate, EndDate) {
  // The number of milliseconds in all UTC days (no DST)
  const oneDay = 1000 * 60 * 60 * 24;

  // A day in UTC always lasts 24 hours (unlike in other time formats)
  const start = Date.UTC(EndDate.getFullYear(), EndDate.getMonth(), EndDate.getDate());
  const end = Date.UTC(StartDate.getFullYear(), StartDate.getMonth(), StartDate.getDate());

  // so it's safe to divide by 24 hours
  return (start - end) / oneDay;

How to change values in a tuple?

I've found the best way to edit tuples is to recreate the tuple using the previous version as the base.

Here's an example I used for making a lighter version of a colour (I had it open already at the time):

colour = tuple([c+50 for c in colour])

What it does, is it goes through the tuple 'colour' and reads each item, does something to it, and finally adds it to the new tuple.

So what you'd want would be something like:

values = ('275', '54000', '0.0', '5000.0', '0.0')

values  = (tuple(for i in values: if i = 0: i = 200 else i = values[i])

That specific one doesn't work, but the concept is what you need.

tuple = (0, 1, 2)

tuple = iterate through tuple, alter each item as needed

that's the concept.

Search for exact match of string in excel row using VBA Macro

Try this:

Sub GetColumns()

Dim lnRow As Long, lnCol As Long

lnRow = 3 'For testing

lnCol = Sheet1.Cells(lnRow, 1).EntireRow.Find(What:="sds", LookIn:=xlValues, LookAt:=xlPart, SearchOrder:=xlByColumns, SearchDirection:=xlNext, MatchCase:=False).Column

End Sub

Probably best not to use colIndex and rowIndex as variable names as they are already mentioned in the Excel Object Library.

Comparing arrays in JUnit assertions, concise built-in way?

Class Assertions in org.junit.jupiter.api


public static void assertArrayEquals(int[] expected,
                                     int[] actual)

Convert a string representation of a hex dump to a byte array using Java?

In android ,if you are working with hex, you can try okio.

simple usage:

byte[] bytes = ByteString.decodeHex("c000060000").toByteArray();

and result will be

[-64, 0, 6, 0, 0]

Get all child elements

Yes, you can achieve it by find_elements_by_css_selector("*") or find_elements_by_xpath(".//*").

However, this doesn't sound like a valid use case to find all children of an element. It is an expensive operation to get all direct/indirect children. Please further explain what you are trying to do. There should be a better way.

from selenium import webdriver

driver = webdriver.Firefox()

header = driver.find_element_by_id("header")

# start from your target element, here for example, "header"
all_children_by_css = header.find_elements_by_css_selector("*")
all_children_by_xpath = header.find_elements_by_xpath(".//*")

print 'len(all_children_by_css): ' + str(len(all_children_by_css))
print 'len(all_children_by_xpath): ' + str(len(all_children_by_xpath))

How to correctly set the ORACLE_HOME variable on Ubuntu 9.x?

This is the right way to clear this error.

export ORACLE_HOME=/u01/app/oracle/product/10.2.0/db_1 sqlplus / as sysdba

How to handle AssertionError in Python and find out which line or statement it occurred on?

The traceback module and sys.exc_info are overkill for tracking down the source of an exception. That's all in the default traceback. So instead of calling exit(1) just re-raise:

    assert "birthday cake" == "ice cream cake", "Should've asked for pie"
except AssertionError:
    print 'Houston, we have a problem.'

Which gives the following output that includes the offending statement and line number:

Houston, we have a problem.
Traceback (most recent call last):
  File "/tmp/", line 2, in <module>
    assert "birthday cake" == "ice cream cake", "Should've asked for pie"
AssertionError: Should've asked for pie

Similarly the logging module makes it easy to log a traceback for any exception (including those which are caught and never re-raised):

import logging

    assert False == True 
except AssertionError:
    logging.error("Nothing is real but I can't quit...", exc_info=True)

Visual Studio: ContextSwitchDeadlock

As Pedro said, you have an issue with the debugger preventing the message pump if you are stepping through code.

But if you are performing a long running operation on the UI thread, then call Application.DoEvents() which explicitly pumps the message queue and then returns control to your current method.

However if you are doing this I would recommend at looking at your design so that you can perform processing off the UI thread so that your UI remains nice and snappy.

How to update value of a key in dictionary in c#?

Have you tried just

dictionary["cat"] = 5;



dictionary["cat"] = 5+2;
dictionary["cat"] = dictionary["cat"]+2;
dictionary["cat"] += 2;

Beware of non-existing keys :)

Why does JSON.parse fail with the empty string?

For a valid JSON string at least a "{}" is required. See more at the

gradient descent using python and numpy

Below you can find my implementation of gradient descent for linear regression problem.

At first, you calculate gradient like X.T * (X * w - y) / N and update your current theta with this gradient simultaneously.

  • X: feature matrix
  • y: target values
  • w: weights/values
  • N: size of training set

Here is the python code:

import pandas as pd
import numpy as np
from matplotlib import pyplot as plt
import random

def generateSample(N, variance=100):
    X = np.matrix(range(N)).T + 1
    Y = np.matrix([random.random() * variance + i * 10 + 900 for i in range(len(X))]).T
    return X, Y

def fitModel_gradient(x, y):
    N = len(x)
    w = np.zeros((x.shape[1], 1))
    eta = 0.0001

    maxIteration = 100000
    for i in range(maxIteration):
        error = x * w - y
        gradient = x.T * error / N
        w = w - eta * gradient
    return w

def plotModel(x, y, w):
    plt.plot(x[:,1], y, "x")
    plt.plot(x[:,1], x * w, "r-")

def test(N, variance, modelFunction):
    X, Y = generateSample(N, variance)
    X = np.hstack([np.matrix(np.ones(len(X))).T, X])
    w = modelFunction(X, Y)
    plotModel(X, Y, w)

test(50, 600, fitModel_gradient)
test(50, 1000, fitModel_gradient)
test(100, 200, fitModel_gradient)

test1 test2 test2

How to get file creation & modification date/times in Python?


edit: In newer code you should probably use os.path.getmtime() (thanks Christian Oudard)
but note that it returns a floating point value of time_t with fraction seconds (if your OS supports it)

What programming language does facebook use?

might be surprised to know.. its PHP. read all about it here

How to check java bit version on Linux?

Why don't you examine System.getProperty("os.arch") value in your code?

command/usr/bin/codesign failed with exit code 1- code sign error

I had the same error on January 2018 with xcode 8.2.1

Before I try to open xcode I couldn't because the system was updating. I tried sometime later and it let me working on it, and then I got the same error.

I followed most of the solutions described in this article but they didn't work for me.

Then I remembered the message about the system updating and I tried to reboot the machine.

And that did the magic. It worked for me.

How to test if JSON object is empty in Java

public void emptyJsonParseTest() {
    JsonNode emptyJsonNode = new ObjectMapper().createObjectNode();

No 'Access-Control-Allow-Origin' header is present on the requested resource- AngularJS

This is how it worked for me. For Windows users testing with Bracket and AngularJS

1) Go to your desktop

2) Right click on your desktop and look for "NEW" in the popup drop down dialog box and it will expand

3) Choose Shortcut

4) A dialog box will open

5) Click on Browse and look for Google Chrome.

6) Click Ok->Next->Finish and it will create the google shortcut on your desktop

7) Now Right Click on the Google Chrome icon you just created

8) Click properties

9) Enter this in the target path

"C:\Program Files\Google\Chrome\Application\chrome.exe" --args --disable-web-security

10) Save it

11) Double click on your newly created chrome shortcut and past your link in the address bar and it will work.

Could not calculate build plan: Plugin org.apache.maven.plugins:maven-jar-plugin:2.3.2 or one of its dependencies could not be resolved

In my case the error was: CoreException: Could not calculate build plan: Plugin org.apache.maven.plugins:maven-compiler-plugin:2.3.2 ....

With eclipse luna from console in the pom.xml folder

mvn clean
mvn install

With Juno I had to had this to my pom.xml

            <!-- put your configurations here -->

And then

mvn install

And then from eclipse right click>maven>update project * Once the plugin is donwloaded you can remove the plugin from your pom.xml

Removing time from a Date object?

You can write that for example:

private Date TruncarFecha(Date fechaParametro) throws ParseException {
    String fecha="";
    DateFormat outputFormatter = new SimpleDateFormat("MM/dd/yyyy");
    fecha =outputFormatter.format(fechaParametro);
    return outputFormatter.parse(fecha);

Unordered List (<ul>) default indent

I'll tackle your second question first. Yes, the indentation can be reset by using a browser reset like Eric Meyers. Or a simple ul { margin: 0; padding: 0;} as indentation is, by default, enforced on the ul element.

As to the why, I suspect its to do with the current level of nesting, as unordered lists allow for nesting or maybe to do with the bullets positioning.

Edit: As Guffa mentioned, the list indentation is to ensure that the markers do not fall off the left edge.

ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use

I encountered this same error: ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ', completed)' at line 1

This was the input I had entered on terminal: mysql> create table todos (description, completed);

Solution: For each column type you must specify the type of content they will contain. This could either be text, integer, variable, boolean there are many different types of data.

mysql> create table todos (description text, completed boolean);

Query OK, 0 rows affected (0.02 sec)

It now passed successfully.

PHP Fatal error: Using $this when not in object context

When you call the function in a static context, $this simply doesn't exist.

You would have to use this::xyz() instead.

To find out what context you're in when a function can be called both statically and in an object instance, a good approach is outlined in this question: How to tell whether I’m static or an object?

Creating an XmlNode/XmlElement in C# without an XmlDocument?

XmlDocumnt xdoc = new XmlDocument;
XmlNode songNode = xdoc.CreateNode(XmlNodeType.Element, "Song", schema)

How do I select an element in jQuery by using a variable for the ID?

You can do it like this:

row_id = 5;
row = $("body").find('#'+row_id);

GCC dump preprocessor defines

Yes, use -E -dM options instead of -c. Example (outputs them to stdout):

 gcc -dM -E - < /dev/null

For C++

 g++ -dM -E -x c++ - < /dev/null

From the gcc manual:

Instead of the normal output, generate a list of `#define' directives for all the macros defined during the execution of the preprocessor, including predefined macros. This gives you a way of finding out what is predefined in your version of the preprocessor. Assuming you have no file foo.h, the command

touch foo.h; cpp -dM foo.h

will show all the predefined macros.

If you use -dM without the -E option, -dM is interpreted as a synonym for -fdump-rtl-mach.

Transitions on the CSS display property

I finally found a solution for me, by combining opacity with position absolute (not to occupy space when hidden).

.toggle {
  opacity: 0;
  position: absolute;
  transition: opacity 0.8s;

.parent:hover .toggle {
  opacity: 1;
  position: static;

What are the differences between json and simplejson Python modules?

I came across this question as I was looking to install simplejson for Python 2.6. I needed to use the 'object_pairs_hook' of json.load() in order to load a json file as an OrderedDict. Being familiar with more recent versions of Python I didn't realize that the json module for Python 2.6 doesn't include the 'object_pairs_hook' so I had to install simplejson for this purpose. From personal experience this is why i use simplejson as opposed to the standard json module.

MySQL Insert into multiple tables? (Database normalization?)

try this

$sql= " INSERT INTO users (username, password) VALUES('test', 'test') ";
$user_id= mysql_insert_id();
if(!empty($user_id) {

$sql=INSERT INTO profiles (userid, bio, homepage) VALUES($user_id,'Hello world!', '');
/* or 
 $sql=INSERT INTO profiles (userid, bio, homepage) VALUES(LAST_INSERT_ID(),'Hello   world!', ''); */


Add support library to Android Studio project

You can simply download the library which you want to include and copy it to libs folder of your project. Then select that file (in my case it was android-support-v4 library) right click on it and select "Add as Library"

How to get nth jQuery element

I think you can use this

$("ul li:nth-child(2)").append("<span> - 2nd!</span>");

It finds the second li in each matched ul and notes it.

How to add an empty column to a dataframe?

I like:

df['new'] = pd.Series(dtype='your_required_dtype')

If you have an empty dataframe, this solution makes sure that no new row containing only NaN is added.

Specifying dtype is not strictly necessary, however newer Pandas versions produce a DeprecationWarning if not specified.

JavaFX Panel inside Panel auto resizing

I was designing a GUI in SceneBuilder, trying to make the main container adapt to whatever the window size is. It should always be 100% wide.

This is where you can set these values in SceneBuilder:

AnchorPane Constraints in SceneBuilder

Toggling the dotted/red lines will actually just add/remove the attributes that Korki posted in his solution (AnchorPane.topAnchor etc.).

How do you uninstall all dependencies listed in package.json (NPM)?

I recently found a node command that allows uninstalling all the development dependencies as follows:

npm prune --production

As I mentioned, this command only uninstalls the development dependency packages. At least it helped me not to have to do it manually.

Type List vs type ArrayList in Java

Somebody asked this again (duplicate) which made me go a little deeper on this issue.

public static void main(String[] args) {
    List<String> list = new ArrayList<String>();

    ArrayList<String> aList = new ArrayList<String>();


If we use a bytecode viewer (I used well see the following (only list initialization and assignment) for our list snippet:

    NEW ArrayList
    INVOKESPECIAL ArrayList.<init> () : void
    ASTORE 1
    ALOAD 1: list
    LDC "a"
    INVOKEINTERFACE List.add (Object) : boolean
    ALOAD 1: list
    LDC "b"
    INVOKEINTERFACE List.add (Object) : boolean

and for alist:

    NEW java/util/ArrayList
    INVOKESPECIAL java/util/ArrayList.<init> ()V
    ASTORE 2
    ALOAD 2
    LDC "a"
    INVOKEVIRTUAL java/util/ArrayList.add (Ljava/lang/Object;)Z
    ALOAD 2
    LDC "b"
    INVOKEVIRTUAL java/util/ArrayList.add (Ljava/lang/Object;)Z

The difference is list ends up calling INVOKEINTERFACE whereas aList calls INVOKEVIRTUAL. Accoding to the Bycode Outline Plugin reference,

invokeinterface is used to invoke a method declared within a Java interface

while invokevirtual

invokes all methods except interface methods (which use invokeinterface), static methods (which use invokestatic), and the few special cases handled by invokespecial.

In summary, invokevirtual pops objectref off the stack while for invokeinterface

the interpreter pops 'n' items off the operand stack, where 'n' is an 8-bit unsigned integer parameter taken from the bytecode. The first of these items is objectref, a reference to the object whose method is being called.

If I understand this correctly, the difference is basically how each way retrieves objectref.

Linq code to select one item

FirstOrDefault or SingleOrDefault might be useful, depending on your scenario, and whether you want to handle there being zero or more than one matches:

FirstOrDefault: Returns the first element of a sequence, or a default value if no element is found.

SingleOrDefault: Returns the only element of a sequence, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence

I don't know how this works in a linq 'from' query but in lambda syntax it looks like this:

var item1 = Items.FirstOrDefault(x => x.Id == 123);
var item2 = Items.SingleOrDefault(x => x.Id == 123);

How to initialize an array of custom objects

The simplest way to initialize an array

Create array

$array = @()

Create your header

$line = "" | select name,age,phone

Fill the line

$ = "Leandro"
$line.age = "39"
$ = "555-555555"

Add line to $array

$array += $line



name                                                     age                                                      phone
----                                                     ---                                                      -----
Leandro                                                  39                                                       555-555555

What is a good naming convention for vars, methods, etc in C++?

While many people will suggest more or less strict Hungarian notation variants (scary!), for naming suggestions I'd suggest you take a look at Google C++ Coding Guidelines. This may well be not the most popular naming conventions, but at least it's fairly complete. Apart from sound naming conventions, there's some useful guidelines there, however much of it should be taken with a grain of salt (exception ban for example, and the tendency to keep away from modern C++ coding style).

Although personally I like the extreme low-tech convention style of STL and Boost ;).

How to do perspective fixing?

The simple solution is to just remap coordinates from the original to the final image, copying pixels from one coordinate space to the other, rounding off as necessary -- which may result in some pixels being copied several times adjacent to each other, and other pixels being skipped, depending on whether you're stretching or shrinking (or both) in either dimension. Make sure your copying iterates through the destination space, so all pixels are covered there even if they're painted more than once, rather than thru the source which may skip pixels in the output.

The better solution involves calculating the corresponding source coordinate without rounding, and then using its fractional position between pixels to compute an appropriate average of the (typically) four pixels surrounding that location. This is essentially a filtering operation, so you lose some resolution -- but the result looks a LOT better to the human eye; it does a much better job of retaining small details and avoids creating straight-line artifacts which humans find objectionable.

Note that the same basic approach can be used to remap flat images onto any other shape, including 3D surface mapping.

Get File Path (ends with folder)

If you want to browse to a folder by default: For example "D:\Default_Folder" just initialise the "InitialFileName" attribute

Dim diaFolder As FileDialog

' Open the file dialog
Set diaFolder = Application.FileDialog(msoFileDialogFolderPicker)
diaFolder.AllowMultiSelect = False
diaFolder.InitialFileName = "D:\Default_Folder"

How can I change the date format in Java?


    "23/01/2017" ,  
    DateTimeFormatter.ofPattern( "dd/MM/uuuu" , Locale.UK ) 
    DateTimeFormatter.ofPattern( "uuuu/MM/dd" , Locale.UK )


Avoid legacy date-time classes

The answer by Christopher Parker is correct but outdated. The troublesome old date-time classes such as java.util.Date, java.util.Calendar, and java.text.SimpleTextFormat are now legacy, supplanted by the java.time classes.

Using java.time

Parse the input string as a date-time object, then generate a new String object in the desired format.

The LocalDate class represents a date-only value without time-of-day and without time zone.

DateTimeFormatter fIn = DateTimeFormatter.ofPattern( "dd/MM/uuuu" , Locale.UK );  // As a habit, specify the desired/expected locale, though in this case the locale is irrelevant.
LocalDate ld = LocalDate.parse( "23/01/2017" , fIn );

Define another formatter for the output.

DateTimeFormatter fOut = DateTimeFormatter.ofPattern( "uuuu/MM/dd" , Locale.UK );
String output = ld.format( fOut );


By the way, consider using standard ISO 8601 formats for strings representing date-time values.

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

Where to obtain the java.time classes?

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.


UPDATE: The Joda-Time project is now in maintenance mode, with the team advising migration to the java.time classes. This section here is left for the sake of history.

For fun, here is his code adapted for using the Joda-Time library.

// © 2013 Basil Bourque. This source code may be used freely forever by anyone taking full responsibility for doing so.
// import org.joda.time.*;
// import org.joda.time.format.*;

final String OLD_FORMAT = "dd/MM/yyyy";
final String NEW_FORMAT = "yyyy/MM/dd";

// August 12, 2010
String oldDateString = "12/08/2010";
String newDateString;

DateTimeFormatter formatterOld = DateTimeFormat.forPattern(OLD_FORMAT);
DateTimeFormatter formatterNew = DateTimeFormat.forPattern(NEW_FORMAT);
LocalDate localDate = formatterOld.parseLocalDate( oldDateString );
newDateString = formatterNew.print( localDate );

Dump to console…

System.out.println( "localDate: " + localDate );
System.out.println( "newDateString: " + newDateString );

When run…

localDate: 2010-08-12
newDateString: 2010/08/12

Android Facebook 4.0 SDK How to get Email, Date of Birth and gender of User

Here's a working solution (2019): put this code inside your login logic;

 GraphRequest request = GraphRequest.newMeRequest(loginResult.getAccessToken(), new GraphRequest.GraphJSONObjectCallback() {
                public void onCompleted(JSONObject json, GraphResponse response) {
                    // Application code
                    if (response.getError() != null) {
                    } else {
                        String jsonresult = String.valueOf(json);
                        System.out.println("JSON Result" + jsonresult);

                        String fbUserId = json.optString("id");
                        String fbUserFirstName = json.optString("name");
                        String fbUserEmail = json.optString("email");
                        //String fbUserProfilePics = "" + fbUserId + "/picture?type=large";
                        Log.d("SignUpActivity", "Email: " + fbUserEmail + "\nName: " + fbUserFirstName + "\nID: " + fbUserId);
                    Log.d("SignUpActivity", response.toString());
            Bundle parameters = new Bundle();
            parameters.putString("fields", "id,name,email,gender, birthday");

        public void onCancel() {
            Toast.makeText(SignUpActivity.this, "Login Attempt Cancelled", Toast.LENGTH_SHORT).show();

        public void onError(FacebookException error) {
            Toast.makeText(SignUpActivity.this, "An Error Occurred", Toast.LENGTH_LONG).show();

Javascript geocoding from address to latitude and longitude numbers not working

Try using this instead:

var latitude = results[0];
var longitude = results[0].geometry.location.lng();

It's bit hard to navigate Google's api but here is the relevant documentation.

One thing I had trouble finding was how to go in the other direction. From coordinates to an address. Here is the code I neded upp using. Please not that I also use jquery.

$.each(results[0].address_components, function(){
    $("#CreateDialog").find('input[name="'+ this.types+'"]').attr('value', this.long_name);

What I'm doing is to loop through all the returned address_components and test if their types match any input element names I have in a form. And if they do I set the value of the element to the address_components value.
If you're only interrested in the whole formated address then you can follow Google's example

how to draw a rectangle in HTML or CSS?

the css you are showing must be applied to a block element, like a div. So :

<div id="#rectangle"></div>

How can I see the entire HTTP request that's being sent by my Python application?

If you're using Python 2.x, try installing a urllib2 opener. That should print out your headers, although you may have to combine that with other openers you're using to hit the HTTPS.

import urllib2

Accessing value inside nested dictionaries

No, those are nested dictionaries, so that is the only real way (you could use get() but it's the same thing in essence). However, there is an alternative. Instead of having nested dictionaries, you can use a tuple as a key instead:

tempDict = {("ONE", "TWO", "THREE"): 10}
tempDict["ONE", "TWO", "THREE"]

This does have a disadvantage, there is no (easy and fast) way of getting all of the elements of "TWO" for example, but if that doesn't matter, this could be a good solution.

Setting timezone in Python

It's not an answer, but...

To get datetime components individually, better use datetime.timetuple:

time =
#-> time.struct_time(
#    tm_year=2014, tm_mon=9, tm_mday=7, 
#    tm_hour=2, tm_min=38, tm_sec=5, 
#    tm_wday=6, tm_yday=250, tm_isdst=-1

It's now easy to get the parts:

ts = time.timetuple()

How to asynchronously call a method in Java

Java 8 introduced CompletableFuture available in package java.util.concurrent.CompletableFuture, can be used to make a asynch call :

CompletableFuture.runAsync(() -> {
    // method call or code to be asynch.

Loop through all the files with a specific extension

Recursively add subfolders,

for i in `find . -name "*.java" -type f`; do
    echo "$i"

Bootstrap trying to load map file. How to disable it? Do I need to do it?

.map files allow a browser to download a full version of the minified JS. It is really for debugging purposes.

In effect, the .map missing isn't a problem. You only know it is missing, as the browser has had its Developer tools opened, detected a minified file and is just informing you that the JS debugging won't be as good as it could be.

This is why libraries like jQuery have the full, the minified and the map file too.

See this article for a full explanation of .map files:

Evaluate expression given as a string

Not sure why no one has mentioned two Base R functions specifically to do this: str2lang() and str2expression(). These are variants of parse(), but seem to return the expression more cleanly:


# > 10

# > 10

Also want to push back against the posters saying that anyone trying to do this is wrong. I'm reading in R expressions stored as text in a file and trying to evaluate them. These functions are perfect for this use case.

How to Delete a directory from Hadoop cluster which is having comma(,) in its name?

Try hadoop dfs -rm -r hdfs://host:port/Navi/MyDir\,\ Name now

PHP fopen() Error: failed to open stream: Permission denied

[function.fopen]: failed to open stream

If you have access to your php.ini file, try enabling Fopen. Find the respective line and set it to be "on": & if in wp e.g localhost/wordpress/function.fopen in the php.ini :

allow_url_fopen = off
should bee this 
allow_url_fopen = On

And add this line below it:
allow_url_include = off
should bee this 
allow_url_include = on

Set attribute without value

Perhaps try:

var body = document.getElementsByTagName('body')[0];

How to render a DateTime object in a Twig template

I know this is a pretty old question, but I found this question today, but the answers were not what I needed.

So here's what I needed.

If you, like me, are looking to display the current date in twig, you can use the following:

{{ "now"|date("m/d/Y") }}

See documentation about this:

date in twig

pytest cannot import module while python can

I disagree with the posts saying that you must remove any files. What you must instead do is alter the sys.path.

Run an experiment where you print sys.path when running the code normally. Then print sys.path while running the code via pytest. I think you will find that there is a difference between these two paths, hence why pytest breaks.

To fix this, insert the path from the first experiment at the 0th index of the second.

Let '/usr/exampleUser/Documents/foo' be the first element of print(sys.path) for experiment 1.

Below is code that should fix your issue:

import sys sys.path[0] = '/usr/exampleUser/Documents/foo'

Put this at the top of your file, before your actual import statement.

Source: I was dealing with this myself and the above process solved it.

Convert txt to csv python script

This is how I do it:

 with open(txtfile, 'r') as infile, open(csvfile, 'w') as outfile:
        stripped = (line.strip() for line in infile)
        lines = (line.split(",") for line in stripped if line)
        writer = csv.writer(outfile)

Hope it helps!

What is the equivalent of Select Case in Access SQL?

Consider the Switch Function as an alternative to multiple IIf() expressions. It will return the value from the first expression/value pair where the expression evaluates as True, and ignore any remaining pairs. The concept is similar to the SELECT ... CASE approach you referenced but which is not available in Access SQL.

If you want to display a calculated field as commission:

        OpeningBalance < 5001, 20,
        OpeningBalance < 10001, 30,
        OpeningBalance < 20001, 40,
        OpeningBalance >= 20001, 50
        ) AS commission
FROM YourTable;

If you want to store that calculated value to a field named commission:

UPDATE YourTable
SET commission =
        OpeningBalance < 5001, 20,
        OpeningBalance < 10001, 30,
        OpeningBalance < 20001, 40,
        OpeningBalance >= 20001, 50

Either way, see whether you find Switch() easier to understand and manage. Multiple IIf()s can become mind-boggling as the number of conditions grows.

Why should I use var instead of a type?

When you say "by warnings" what exactly do you mean? I've usually seen it giving a hint that you may want to use var, but nothing as harsh as a warning.

There's no performance difference with var - the code is compiled to the same IL. The potential benefit is in readability - if you've already made the type of the variable crystal clear on the RHS of the assignment (e.g. via a cast or a constructor call), where's the benefit of also having it on the LHS? It's a personal preference though.

If you don't want R# suggesting the use of var, just change the options. One thing about ReSharper: it's very configurable :)

Matrix Transpose in Python

def matrixTranspose(anArray):
  transposed = [None]*len(anArray[0])

  for i in range(len(transposed)):
    transposed[i] = [None]*len(transposed)

  for t in range(len(anArray)):
    for tt in range(len(anArray[t])):            
        transposed[t][tt] = anArray[tt][t]
  return transposed

theArray = [['a','b','c'],['d','e','f'],['g','h','i']]

print matrixTranspose(theArray)

Save array in mysql database

$myArray = new array('1', '2');
$seralizedArray = serialize($myArray);

How to make an element width: 100% minus padding?

For me, using margin:15px;padding:10px 0 15px 23px;width:100%, the result was this:

enter image description here

The solution for me was to use width:auto instead of width:100%. My new code was:

margin:15px;padding:10px 0 15px 23px;width:auto. Then the element aligned properly:

enter image description here

How to position two divs horizontally within another div

Something like this perhaps...


            #head, #sub-title

            #sub-left, #sub-right


        <div id="container">
            <div id="head">
            <div id="sub-title">
                <div id="sub-left">

                <div id="sub-right">

Oracle Sql get only month and year in date datatype

Easiest solution is to create the column using the correct data type: DATE

For example:

  1. Create table:

    create table test_date (mydate date);

  2. Insert row:

    insert into test_date values (to_date('01-01-2011','dd-mm-yyyy'));

To get the month and year, do as follows:

select to_char(mydate, 'MM-YYYY') from test_date;

Your result will be as follows: 01-2011

Another cool function to use is "EXTRACT"

select extract(year from mydate) from test_date;

This will return: 2011

Can not deserialize instance of java.lang.String out of START_ARRAY token

The error is:

Can not deserialize instance of java.lang.String out of START_ARRAY token at [Source: line: 1, column: 1095] (through reference chain: JsonGen["platforms"])

In JSON, platforms look like this:

"platforms": [
        "platform": "iphone"
        "platform": "ipad"
        "platform": "android_phone"
        "platform": "android_tablet"

So try change your pojo to something like this:

private List platforms;

public List getPlatforms(){
    return this.platforms;

public void setPlatforms(List platforms){
    this.platforms = platforms;

EDIT: you will need change mobile_networks too. Will look like this:

private List mobile_networks;

public List getMobile_networks() {
    return mobile_networks;

public void setMobile_networks(List mobile_networks) {
    this.mobile_networks = mobile_networks;

getSupportActionBar() The method getSupportActionBar() is undefined for the type TaskActivity. Why?

If you are already extending from ActionBarActivity and you are trying to get the action bar from a fragment:

ActionBar mActionBar = (ActionBarActivity)getActivity()).getSupportActionBar();

Fastest way to count number of occurrences in a Python list

Combination of lambda and map function can also do the job:

list_ = ['a', 'b', 'b', 'c']
sum(map(lambda x: x=="b", list_))

How to sleep for five seconds in a batch file/cmd

This should do the trick: choice /T 5 /N /D Y

Replace the 5 with the time in seconds you want to wait...

Java - No enclosing instance of type Foo is accessible

You've declared the class Thing as a non-static inner class. That means it must be associated with an instance of the Hello class.

In your code, you're trying to create an instance of Thing from a static context. That is what the compiler is complaining about.

There are a few possible solutions. Which solution to use depends on what you want to achieve.

  • Move Thing out of the Hello class.

  • Change Thing to be a static nested class.

    static class Thing
  • Create an instance of Hello before creating an instance of Thing.

    public static void main(String[] args)
        Hello h = new Hello();
        Thing thing1 = Thing(); // hope this syntax is right, typing on the fly :P

The last solution (a non-static nested class) would be mandatory if any instance of Thing depended on an instance of Hello to be meaningful. For example, if we had:

public class Hello {
    public int enormous;

    public Hello(int n) {
        enormous = n;

    public class Thing {
        public int size;

        public Thing(int m) {
            if (m > enormous)
                size = enormous;
                size = m;

any raw attempt to create an object of class Thing, as in:

Thing t = new Thing(31);

would be problematic, since there wouldn't be an obvious enormous value to test 31 against it. An instance h of the Hello outer class is necessary to provide this h.enormous value:

Hello h = new Hello(30);
Thing t = Thing(31);

Because it doesn't mean a Thing if it doesn't have a Hello.

For more information on nested/inner classes: Nested Classes (The Java Tutorials)

How to get height and width of device display in angular2 using typescript?

export class Dashboard {
    innerHeight: any;
    innerWidth: any;
    constructor() {
        this.innerHeight = (window.screen.height) + "px";
        this.innerWidth = (window.screen.width) + "px";

Java to Jackson JSON serialization: Money fields

I had the same issue and i had it formatted into JSON as a String instead. Might be a bit of a hack but it's easy to implement.

private BigDecimal myValue = new BigDecimal("25.50");
public String getMyValue() {
    return myValue.setScale(2, BigDecimal.ROUND_HALF_UP).toString();

Disable vertical sync for glxgears

I found a solution that works in the intel card and in the nvidia card using Bumblebee.

> export vblank_mode=0
optirun glxgears
export vblank_mode=1

Add tooltip to font awesome icon

In regards to this question, this can be easily achieved using a few lines of SASS;


<a href="" data-tool-tip="What's a tech ninja?" target="_blank"><i class="fas fa-2x fa-user-ninja" id="tech--ninja"></i></a>

CSS output would be:

    position: relative;
    text-decoration: none;
    color: rgba(255,255,255,0.75);

    content: attr(data-tool-tip);
    display: block;
    position: absolute;
    background-color: dimgrey;
    padding: 1em 3em;
    color: white;
    border-radius: 5px;
    font-size: .5em;
    bottom: 0;
    left: -180%;
    white-space: nowrap;
    transform: scale(0);
    transform ease-out 150ms,
    bottom ease-out 150ms;

    transform: scale(1);
    bottom: 200%;

Basically the attribute selector [data-tool-tip] selects the content of whatever's inside and allows you to animate it however you want.

Git/GitHub can't push to master

If you go to you will see a textbox where you can select the git path to your repository. You'll want to use this!

Sending a file over TCP sockets in Python

You can send some flag to stop while loop in server

for example

Server side:

import socket
s = socket.socket()
s.bind(("localhost", 5000))
c,a = s.accept()
filetodown = open("img.png", "wb")
while True:
   data = c.recv(1024)
   if data == b"DONE":
           print("Done Receiving.")
c.send("Thank you for connecting.")
#Done :)

Client side:

import socket
s = socket.socket()
s.connect(("localhost", 5000))
filetosend = open("img.png", "rb")
data =
while data:
    data =
print("Done Sending.")
#Done :)

Finding the mode of a list

Python 3.4 includes the method statistics.mode, so it is straightforward:

>>> from statistics import mode
>>> mode([1, 1, 2, 3, 3, 3, 3, 4])

You can have any type of elements in the list, not just numeric:

>>> mode(["red", "blue", "blue", "red", "green", "red", "red"])

Application not picking up .css file (flask/python)

I'm pretty sure it's similar to Laravel template, this is how I did mine.

<link rel="stylesheet" href="/folder/stylesheets/stylesheet.css" />

Referred: CSS file pathing problem

Simple flask application that reads its content from a .html file. External style sheet being blocked?

Update Android SDK Tool to 22.0.4(Latest Version) from 22.0.1

I faced the same issue, I tried the below solution and it worked for me In Android SDK Manager Window, click on Tools->Options-> under "Others", check "Force https://... sources to be fetched using http://..."

Oracle - Why does the leading zero of a number disappear when converting it TO_CHAR

Should work in all cases:

SELECT regexp_replace(0.1234, '^(-?)([.,])', '\10\2') FROM dual

Print commit message of a given commit in git

I use shortlog for this:

$ git shortlog master..
Username (3):
      Write something
      Add something
      Bump to 1.3.8 

getElementById returns null?

Also be careful how you execute the js on the page. For example if you do something like this:

(function(window, document, undefined){

  var foo = document.getElementById("foo");


})(window, document, undefined); 

This will return null because you'd be calling the document before it was loaded.

Better option..

(function(window, document, undefined){

// code that should be taken care of right away

window.onload = init;

  function init(){
    // the code to be called when the dom has loaded
    // #document has its nodes

})(window, document, undefined);

Where does Jenkins store configuration files for the jobs it runs?

On Linux one can find the home directory of Jenkins looking for a file, that Jenkins' home contains, e.g.:

$ find / -name "config.xml" | grep "jenkins"

How to use in jQuery :not and hasClass() to get a specific element without a class

I don't know if this was true at the time of the original posting, but the siblings method allows selectors, so a reduction of what the OP listed should work.


How to update two tables in one statement in SQL Server 2005?

You should place two update statements inside a transaction

Sorting a DropDownList? - C#, ASP.NET

Try it

-------Store Procedure-----(SQL)

USE [Your Database]

CRATE PROC [dbo].[GetAllDataByID]

@ID int

        SELECT * FROM Your_Table
        WHERE ID=@ID
        ORDER BY Your_ColumnName 


<asp:DropDownList ID="ddlYourTable" runat="server"></asp:DropDownList>


protected void Page_Load(object sender, EventArgs e)


      if (!IsPostBack)
                List<YourTable> table= new List<YourTable>();

                YourtableRepository tableRepo = new YourtableRepository();

                int conuntryInfoID=1;

                table= tableRepo.GetAllDataByID(ID);

                ddlYourTable.DataSource = stateInfo;
                ddlYourTable.DataTextField = "Your_ColumnName";
                ddlYourTable.DataValueField = "ID";


-------LINQ Helper Class----

public class TableRepository


        string connstr;

        public TableRepository() 
            connstr = Settings.Default.YourTableConnectionString.ToString();

        public List<YourTable> GetAllDataByID(int ID)
            List<YourTable> table= new List<YourTable>();
            using (YourTableDBDataContext dc = new YourTableDBDataContext ())
                table= dc.GetAllDataByID(ID).ToList();
            return table;

jQuery on window resize

can use it too

        function getWindowSize()
                var fontSize = parseInt($("body").css("fontSize"), 10);
                var h = ($(window).height() / fontSize).toFixed(4);
                var w = ($(window).width() / fontSize).toFixed(4);              
                var size = {
                      "height": h
                     ,"width": w
                return size;
        function startResizeObserver()
                var colFunc = {
                     "f10" : function(){ alert(10); }
                    ,"f50" : function(){ alert(50); }
                    ,"f100" : function(){ alert(100); }
                    ,"f500" : function(){ alert(500); }
                    ,"f1000" : function(){ alert(1000);}
                $(window).resize(function() {
                    var sz = getWindowSize();
                    if(sz.width > 10){colFunc['f10']();}
                    if(sz.width > 50){colFunc['f50']();}
                    if(sz.width > 100){colFunc['f100']();}
                    if(sz.width > 500){colFunc['f500']();}
                    if(sz.width > 1000){colFunc['f1000']();}

How to pass an object into a state using UI-router?

There are two parts of this problem

1) using a parameter that would not alter an url (using params property):

    .state('login', {
        params: [
        templateUrl: 'partials/login/Login.html'

2) passing an object as parameter: Well, there is no direct way how to do it now, as every parameter is converted to string (EDIT: since 0.2.13, this is no longer true - you can use objects directly), but you can workaround it by creating the string on your own

toParamsJson = JSON.stringify(toStateParams);

and in target controller deserialize the object again

originalParams = JSON.parse($stateParams.toParamsJson);

Why does one use dependency injection?

Quite frankly, I believe people use these Dependency Injection libraries/frameworks because they just know how to do things in runtime, as opposed to load time. All this crazy machinery can be substituted by setting your CLASSPATH environment variable (or other language equivalent, like PYTHONPATH, LD_LIBRARY_PATH) to point to your alternative implementations (all with the same name) of a particular class. So in the accepted answer you'd just leave your code like

var logger = new Logger() //sane, simple code

And the appropriate logger will be instantiated because the JVM (or whatever other runtime or .so loader you have) would fetch it from the class configured via the environment variable mentioned above.

No need to make everything an interface, no need to have the insanity of spawning broken objects to have stuff injected into them, no need to have insane constructors with every piece of internal machinery exposed to the world. Just use the native functionality of whatever language you're using instead of coming up with dialects that won't work in any other project.

P.S.: This is also true for testing/mocking. You can very well just set your environment to load the appropriate mock class, in load time, and skip the mocking framework madness.

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

Literal Answer -- warning, performance may not be as good as just using an int to track the index. At least it is better than using IndexOf.

You just need to use the indexing overload of Select to wrap each item in the collection with an anonymous object that knows the index. This can be done against anything that implements IEnumerable.

System.Collections.IEnumerable collection = Enumerable.Range(100, 10);

foreach (var o in collection.OfType<object>().Select((x, i) => new {x, i}))
    Console.WriteLine("{0} {1}", o.i, o.x);

IIS: Where can I find the IIS logs?

I'm adding this answer because after researching the web, I ended up at this answer but still didn't know which subfolder of the IIS logs folder to look in.

If your server has multiple websites, you will need to know the IIS ID for the site. An easy way to get this in IIS is to simply click on the Sites folder in the left panel. The ID for each site is shown in the right panel.

Once you know the ID, let's call it n, the corresponding logs are in the W3SVCn subfolder of the IIS logs folder. So, if your website ID is 4, say, and the IIS logs are in the default location, then the logs are in this folder:



  • Answer by @jishi tells where the logs are by default.
  • Answer by @Rafid explains how to find actual location (maybe not default).
  • Answer by @Bergius gives a programmatic way to find the log folder location for a specific website, taking ID into account, without using IIS.

CSS container div not getting height

It is not that easier?

.c {
    overflow: auto;

AngularJS ui router passing data between states without URL

We can use params, new feature of the UI-Router:

API Reference / ui.router.state / $stateProvider

params A map which optionally configures parameters declared in the url, or defines additional non-url parameters. For each parameter being configured, add a configuration object keyed to the name of the parameter.

See the part: "...or defines additional non-url parameters..."

So the state def would be:

  .state('home', {
    url: "/home",
    templateUrl: 'tpl.html',
    params: { hiddenOne: null, }

Few examples form the doc mentioned above:

// define a parameter's default value
params: {
  param1: { value: "defaultValue" }
// shorthand default values
params: {
  param1: "defaultValue",
  param2: "param2Default"

// param will be array []
params: {
  param1: { array: true }

// handling the default value in url:
params: {
  param1: {
    value: "defaultId",
    squash: true
} }
// squash "defaultValue" to "~"
params: {
  param1: {
    value: "defaultValue",
    squash: "~"
  } }

EXTEND - working example:

Here is an example of a state definition:

  .state('home', {
      url: "/home",
      params : { veryLongParamHome: null, },
  .state('parent', {
      url: "/parent",
      params : { veryLongParamParent: null, },
  .state('parent.child', { 
      url: "/child",
      params : { veryLongParamChild: null, },

This could be a call using ui-sref:

<a ui-sref="home({veryLongParamHome:'Home--f8d218ae-d998-4aa4-94ee-f27144a21238'

<a ui-sref="parent({ 

<a ui-sref="parent.child({

Check the example here

Simple PHP calculator

$first = doubleval($_POST['first']);
$second = doubleval($_POST['second']);

if($_POST['group1'] == 'add') {
    echo "$first + $second = ".($first + $second);

// etc

How to find out if a Python object is a string?

Python 2

Use isinstance(obj, basestring) for an object-to-test obj.


How to Get enum item name from its value

I have had excellent success with a technique which resembles the X macros pointed to by @RolandXu. We made heavy use of the stringize operator, too. The technique mitigates the maintenance nightmare when you have an application domain where items appear both as strings and as numerical tokens.

It comes in particularily handy when machine readable documentation is available so that the macro X(...) lines can be auto-generated. A new documentation would immediately result in a consistent program update covering the strings, enums and the dictionaries translating between them in both directions. (We were dealing with PCL6 tokens).

And while the preprocessor code looks pretty ugly, all those technicalities can be hidden in the header files which never have to be touched again, and neither do the source files. Everything is type safe. The only thing that changes is a text file containing all the X(...) lines, and that is possibly auto generated.

Add item to Listview control

Add items:

arr[0] = "product_1";
arr[1] = "100";
arr[2] = "10";
itm = new ListViewItem(arr);

Retrieve items:

productName = listView1.SelectedItems[0].SubItems[0].Text;
price = listView1.SelectedItems[0].SubItems[1].Text;
quantity = listView1.SelectedItems[0].SubItems[2].Text;

source code

Docker: Multiple Dockerfiles in project

When working on a project that requires the use of multiple dockerfiles, simply create each dockerfile in a separate directory. For instance,

app/ db/

Each of the above directories will contain their dockerfile. When an application is being built, docker will search all directories and build all dockerfiles.

how to convert a string to date in mysql?

As was told at MySQL Using a string column with date text as a date field, you can do

SELECT  STR_TO_DATE(yourdatefield, '%m/%d/%Y')
FROM    yourtable

You can also handle these date strings in WHERE clauses. For example

SELECT whatever
  FROM yourtable
 WHERE STR_TO_DATE(yourdatefield, '%m/%d/%Y') > CURDATE() - INTERVAL 7 DAY

You can handle all kinds of date/time layouts this way. Please refer to the format specifiers for the DATE_FORMAT() function to see what you can put into the second parameter of STR_TO_DATE().

Caesar Cipher Function in Python

Using map:

def caesar(text, key):
    return ''.join(map(lambda c: 
        chr((ord(c.lower()) - ord('a') + key) % 26 + ord('a')) if c.isalpha() else ''
    , text))

How can I commit files with git?

The command for commiting all changed files:

git commit -a -m 'My commit comments'

-a = all edited files

-m = following string is a comment.

This will commit to your local drives / folders repo. If you want to push your changes to a git server / remotely hosted server, after the above command type:

git push

GitHub's cheat sheet is quite handy.

PowerShell Connect to FTP server and get files

Based on Why does FtpWebRequest download files from the root directory? Can this cause a 553 error?, I wrote a PowerShell script that enabled to download a file from a FTP-Server via explicit FTP over TLS:

# Config
$Username = "USERNAME"
$Password = "PASSWORD"
#e.g. "C:\temp\somefile.txt"
$RemoteFile = "ftp://PATH_TO_REMOTE_FILE"
#e.g. ""

    # Create a FTPWebRequest
    $FTPRequest = [System.Net.FtpWebRequest]::Create($RemoteFile)
    $FTPRequest.Credentials = New-Object System.Net.NetworkCredential($Username,$Password)
    $FTPRequest.Method = [System.Net.WebRequestMethods+Ftp]::DownloadFile
    $FTPRequest.UseBinary = $true
    $FTPRequest.KeepAlive = $false
    $FTPRequest.EnableSsl  = $true
    # Send the ftp request
    $FTPResponse = $FTPRequest.GetResponse()
    # Get a download stream from the server response
    $ResponseStream = $FTPResponse.GetResponseStream()
    # Create the target file on the local system and the download buffer
    $LocalFileFile = New-Object IO.FileStream ($LocalFile,[IO.FileMode]::Create)
    [byte[]]$ReadBuffer = New-Object byte[] 1024
    # Loop through the download

    do {
        $ReadLength = $ResponseStream.Read($ReadBuffer,0,1024)
    while ($ReadLength -ne 0)
}catch [Exception]
    $Request = $_.Exception
    Write-host "Exception caught: $Request"

Directory.GetFiles of certain extension

If you would like to do your filtering in LINQ, you can do it like this:

var ext = new List<string> { "jpg", "gif", "png" };
var myFiles = Directory
    .EnumerateFiles(dir, "*.*", SearchOption.AllDirectories)
    .Where(s => ext.Contains(Path.GetExtension(s).TrimStart(".").ToLowerInvariant()));

Now ext contains a list of allowed extensions; you can add or remove items from it as necessary for flexible filtering.

How do I read a response from Python Requests?

If you push for example image to some API and want the result address(response) back you could do:

import requests
url = ''
data = {"name": filename}
files = {'file': open(full_file_path, 'rb')}
response =, data=data, files=files)
current_url = response.text

Stacking DIVs on top of each other?

Position the outer div however you want, then position the inner divs using absolute. They'll all stack up.

.inner {_x000D_
  position: absolute;_x000D_
<div class="outer">_x000D_
   <div class="inner">1</div>_x000D_
   <div class="inner">2</div>_x000D_
   <div class="inner">3</div>_x000D_
   <div class="inner">4</div>_x000D_

ORA-30926: unable to get a stable set of rows in the source tables

SQL Error: ORA-30926: unable to get a stable set of rows in the source tables
30926. 00000 -  "unable to get a stable set of rows in the source tables"
*Cause:    A stable set of rows could not be got because of large dml
           activity or a non-deterministic where clause.
*Action:   Remove any non-deterministic where clauses and reissue the dml.

This Error occurred for me because of duplicate records(16K)

I tried with unique it worked .

but again when I tried merge without unique same proble occurred Second time it was due to commit

after merge if commit is not done same Error will be shown.

Without unique, Query will work if commit is given after each merge operation.

What's the best way to check if a file exists in C?

Look up the access() function, found in unistd.h. You can replace your function with

if( access( fname, F_OK ) == 0 ) {
    // file exists
} else {
    // file doesn't exist

You can also use R_OK, W_OK, and X_OK in place of F_OK to check for read permission, write permission, and execute permission (respectively) rather than existence, and you can OR any of them together (i.e. check for both read and write permission using R_OK|W_OK)

Update: Note that on Windows, you can't use W_OK to reliably test for write permission, since the access function does not take DACLs into account. access( fname, W_OK ) may return 0 (success) because the file does not have the read-only attribute set, but you still may not have permission to write to the file.

Catch paste input

Script to remove special characters from all fields with class portlet-form-input-field:

// Remove special chars from input field on paste
jQuery('.portlet-form-input-field').bind('paste', function(e) {
    var textInput = jQuery(this);
    setTimeout(function() {
    }, 200);

function replaceSingleEndOfLineCharactersInString(value) {
        // deal with end-of-line characters (\n or \r\n) that will affect string length calculation,
        // also remove all non-printable control characters that can cause XML validation errors
    if (value != "") {
        value = value.replace(/(\x00|\x01|\x02|\x03|\x04|\x05|\x06|\x07|\x08|\x0B|\x0C|\x0E|\x0F|\x10|\x11|\x12|\x13|\x14|\x15|\x16|\x17|\x18|\x19|\x1A|\x1B|\x1C|\x1D|\x1E|\x1F|\x7F)/gm,'');
        return value = value.replace(/(\r\n|\n|\r)/gm,'##').replace(/(\#\#)/gm,"\r\n");

ActionLink htmlAttributes

Replace the desired hyphen with an underscore; it will automatically be rendered as a hyphen:

@Html.ActionLink("Edit", "edit", "markets",
    new { id = 1 },
    new {@class="ui-btn-right", data_icon="gear"})


<form action="markets/Edit/1" class="ui-btn-right" data-icon="gear" .../>

Getting started with OpenCV 2.4 and MinGW on Windows 7

As pointed out by @Nenad Bulatovic one has to be careful while adding libraries(19th step). one should not add any trailing spaces while adding each library line by line. otherwise mingw goes haywire.

Content Type application/soap+xml; charset=utf-8 was not supported by service

I too had the same error in trace logs. My newly created function in API was throwing the same error but to my surprise, the old functions were performing good. The issue was - My contract data members had few variables of type object. soap-xml was not able to handle it well, however, I can see that array of object types (object[]) were getting passed without any issues. Only a simple object type was not getting parsed by soap. This could be one more reason why the services throw the above error.

How does BitLocker affect performance?

My current work machine came with bitlocker, and being an upgrade from the prior model. It only seemed faster to me. What I have found, however, is that bitlocker is more bullet proof than truecrypt, when it comes to accurately laying down the data. I do a lot of work in SAS which constantly writes backup copies to disk as it moves along and shoots a variety of output types to disk at the end. SAS works fine writing output from multithreaded processes back to bitlocker and doesn't seem to know it's there. This has not been the case for me with truecrypt. I'm not sure what happens or how, but I found that processes got out of synch when working with source/output data in a truecrypt container, which is what I installed on my second work computer since it had no bitlocker. The constant backups were shooting to an SSD while the truecrypt results were on a regular HD. Maybe that speed difference helped trip it up. Whatever the cause, I had to quit using truecrypt on that second computer because it made my SAS results out of synch with respect to processing order and it screwed up some of my processes and data. Scary stuff in my world.

I work with people who have successfully used Truecrypt on the exact same computer, but they weren't using a disk intensive app. like SAS.

Bitlocker to Go, the encryption which bitlocker applies to thumb-drives, does slow things down quite a bit when it comes to read/write times. It's not too hard to use as long as you remember your password on the thumbdrive, and are willing to wait for it to format/initialize the drive, but in my experience it made access to the flash drive about 4 times as slow. Don't know why it would slow down a thumb drive and not a disk but that's how it was for me and my coworker.

Based on my success with bitlocker at work, I bought Windows Pro for my home computer to get bitlocker and plan to encrypt some directories with it for things like financials.

Reset select value to default

If using Spring forms, you may need to reset the selected to your options label. You would set your form:select id value to an empty string resets your selection to the label as the default.

<form:select path="myBeanAttribute" id="my_select">
    <form:option value="" label="--Select One--"/>
    <form:options items="${mySelectionValueList}"/>

 $("#reset").on("click", function () {

in the case where there's a reset button. Otherwise


Get name of currently executing test in JUnit 4

public static TestRule watchman = new TestWatcher() {
    protected void starting( final Description description ) {
        String mN = description.getMethodName();
        if ( mN == null ) {
            mN = "setUpBeforeClass..";

        final String s = StringTools.toString( "starting..JUnit-Test: %s.%s", description.getClassName(), mN );
        System.err.println( s );