Programs & Examples On #Lzh

Kubernetes pod gets recreated when deleted

In my case I deployed via a YAML file like kubectl apply -f deployment.yaml and the solution appears to be to delete via kubectl delete -f deployment.yaml

Subversion ignoring "--password" and "--username" options

I had this same issue and solved it by setting up my ~/.ssh/config file to explicitly use the correct username (i.e. the one you use to login to the server, not your local machine). So, for example:

Host server.hostname
  User username

I found this blog post helpful:

Removing All Items From A ComboBox?

Private Sub cmdClear_Click()
    ComboBox1.Value = Null
    ComboBox2.Value = Null
End Sub

How to deep merge instead of shallow merge?

Is there a way to do this?

If npm libraries can be used as a solution, object-merge-advanced from yours truly allows to merge objects deeply and customise/override every single merge action using a familiar callback function. The main idea of it is more than just deep merging — what happens with the value when two keys are the same? This library takes care of that — when two keys clash, object-merge-advanced weighs the types, aiming to retain as much data as possible after merging:

object key merging weighing key value types to retain as much data as possible

First input argument's key is marked #1, second argument's — #2. Depending on each type, one is chosen for the result key's value. In diagram, "an object" means a plain object (not array etc).

When keys don't clash, they all enter the result.

From your example snippet, if you used object-merge-advanced to merge your code snippet:

const mergeObj = require("object-merge-advanced");
const x = { a: { a: 1 } };
const y = { a: { b: 1 } };
const res = console.log(mergeObj(x, y));
// => res = {
//      a: {
//        a: 1,
//        b: 1
//      }
//    }

It's algorithm recursively traverses all input object keys, compares and builds and returns the new merged result.

Can the jQuery UI Datepicker be made to disable Saturdays and Sundays (and holidays)?

This version of code will make u to get the holiday dates from the sql database and disable the specified date in the UI Datepicker

$(document).ready(function (){
  var holiDays = (function () {
    var val = null;
        'async': false,
        'global': false,
        'url': 'getdate.php',
        'success': function (data) {
            val = data;
    return val;
  var natDays = holiDays.split('');

  function nationalDays(date) {
    var m = date.getMonth();
    var d = date.getDate();
    var y = date.getFullYear();

    for (var i = 0; i ‘ natDays.length-1; i++) {
    var myDate = new Date(natDays[i]);
      if ((m == (myDate.getMonth())) && (d == (myDate.getDate())) && (y == (myDate.getFullYear())))
        return [false];
    return [true];

  function noWeekendsOrHolidays(date) {
    var noWeekend = $.datepicker.noWeekends(date);
      if (noWeekend[0]) {
        return nationalDays(date);
      } else {
        return noWeekend;
  $(function() { 
      minDate: 0,
      dateFormat: 'DD, d MM, yy',
      beforeShowDay: noWeekendsOrHolidays,
      showOn: 'button',
      buttonImage: 'images/calendar.gif', 
      buttonImageOnly: true

Create a Database in sql and put you holiday dates in MM/DD/YYYY format as Varchar Put the below contents in a file getdate.php

$sql="SELECT dates FROM holidaydates";
$result = mysql_query($sql);
$chkdate = $_POST['chkdate'];
while($row = mysql_fetch_array($result))
$str .=$row[0].'';
echo $str;

Happy Coding !!!! :-)

Android Debug Bridge (adb) device - no permissions

The cause of that problem has to do with system permissions (thanks @ IsaacCisneros for this suggestion). Somehow HTC Wildfire (and maybe the others) need something more from the system than Samsung devices. Simple solution is to run Eclipse as a root, but this is not very comfortable with non-sudo Linux systems like Fedora.

I've found another way of achieving the same goal, which seems to be more user friendly and is lesser security hole then running entire IDE with super user privileges. Mind this is still only a workaround of the problem. System root usage should be minimalized only to administrative tasks, and “adb” was designed to work with normal user account without SUID. Despite of the fact that the proper setting of SUID is quite secure, every single permission increase is a potential system security hole.

1.Setting ownership of the adb binary (owner – root, owner group - user_group):

chown root:user_group adb

2.Setting permissions with SUID:

chmod 4550 adb

This should result something similar to this (ls -llh):

-r-sr-x---. 1 root user_name 1.2M Jan 8 11:42 adb

After that you will be able to run adb as a root, event though you'll be using your normal user account. You can run Eclipse as a normal user and your HTC should be discovered properly.

./adb devices 
List of devices attached 
HT0BPPY15230    device 

How do you make a div tag into a link

Keep in mind that search spiders don't index JS code. So, if you put your URL inside JS code and make sure to also include it inside a traditional HTML link elsewhere on the page.

That is, if you want the linked pages to be indexed by Google, etc.

How do I get the path of the current executed file in Python?

You can't directly determine the location of the main script being executed. After all, sometimes the script didn't come from a file at all. For example, it could come from the interactive interpreter or dynamically generated code stored only in memory.

However, you can reliably determine the location of a module, since modules are always loaded from a file. If you create a module with the following code and put it in the same directory as your main script, then the main script can import the module and use that to locate itself.


def we_are_frozen():
    # All of the modules are built-in to the interpreter, e.g., by py2exe
    return hasattr(sys, "frozen")

def module_path():
    encoding = sys.getfilesystemencoding()
    if we_are_frozen():
        return os.path.dirname(unicode(sys.executable, encoding))
    return os.path.dirname(unicode(__file__, encoding))


import module_locator
my_path = module_locator.module_path()

If you have several main scripts in different directories, you may need more than one copy of module_locator.

Of course, if your main script is loaded by some other tool that doesn't let you import modules that are co-located with your script, then you're out of luck. In cases like that, the information you're after simply doesn't exist anywhere in your program. Your best bet would be to file a bug with the authors of the tool.

How do I check if a string is unicode or ascii?

For py2/py3 compatibility simply use

import six if isinstance(obj, six.text_type)

anchor jumping by using javascript

I have a button for a prompt that on click it opens the display dialogue and then I can write what I want to search and it goes to that location on the page. It uses javascript to answer the header.

On the .html file I have:

<button onclick="myFunction()">Load Prompt</button>
<span id="test100"><h4>Hello</h4></span>

On the .js file I have

function myFunction() {
    var input = prompt("list or new or quit");

    while(input !== "quit") {
        if(input ==="test100") {
            window.location.hash = 'test100';
// else if(input.indexOf("test100") >= 0) {
//   window.location.hash = 'test100';
//   return;
// }

When I write test100 into the prompt, then it will go to where I have placed span id="test100" in the html file.

I use Google Chrome.

Note: This idea comes from linking on the same page using

<a href="#test100">Test link</a>

which on click will send to the anchor. For it to work multiple times, from experience need to reload the page.

Credit to the people at stackoverflow (and possibly stackexchange, too) can't remember how I gathered all the bits and pieces. ?

How do I use jQuery to redirect?

You forgot the HTTP part:

window.location.href = "";

datetime dtypes in pandas read_csv

There is a parse_dates parameter for read_csv which allows you to define the names of the columns you want treated as dates or datetimes:

date_cols = ['col1', 'col2']
pd.read_csv(file, sep='\t', header=None, names=headers, parse_dates=date_cols)

How to change line width in ggplot?

Line width in ggplot2 can be changed with argument size= in geom_line().

#sample data

enter image description here

How to check if the docker engine and a docker container are running?

For OS X users (Mojave 10.14.3)

Here is what i use in my Bash script to test if Docker is running or not

# Check if docker is running
if ! docker info >/dev/null 2>&1; then
    echo "Docker does not seem to be running, run it first and retry"
    exit 1

jQuery textbox change event

The change event only fires after the input loses focus (and was changed).

org.hibernate.MappingException: Could not determine type for: java.util.Set

You may just need to add @Transient annotations on roles to not serialize the set.

Why does Java have transient fields?

How do I add a new sourceset to Gradle?

Here is how I achieved this without using configurations{ }.

apply plugin: 'java'

sourceCompatibility = JavaVersion.VERSION_1_6

sourceSets {
    integrationTest {
        java {
            srcDir 'src/integrationtest/java'
        resources {
            srcDir 'src/integrationtest/resources'
        compileClasspath += sourceSets.main.runtimeClasspath

task integrationTest(type: Test) {
    description = "Runs Integration Tests"
    testClassesDir = sourceSets.integrationTest.output.classesDir
    classpath += sourceSets.integrationTest.runtimeClasspath

Tested using: Gradle 1.4 and Gradle 1.6

SSIS package creating Hresult: 0x80004005 Description: "Login timeout expired" error

The answer here is not clear, so I wanted to add more detail.

Using the link provided above, I performed the following step.

In my XML config manager I changed the "Provider" to SQLOLEDB.1 rather than SQLNCLI.1. This got me past this error.

This information is available at the link the OP posted in the Answer.

The link the got me there:

How To Inject AuthenticationManager using Java Configuration in a Custom Filter

Override method authenticationManagerBean in WebSecurityConfigurerAdapter to expose the AuthenticationManager built using configure(AuthenticationManagerBuilder) as a Spring bean:

For example:

   public AuthenticationManager authenticationManagerBean() throws Exception {
       return super.authenticationManagerBean();

Open Url in default web browser

You should use Linking.

Example from the docs:

class OpenURLButton extends React.Component {
  static propTypes = { url: React.PropTypes.string };
  handleClick = () => {
    Linking.canOpenURL(this.props.url).then(supported => {
      if (supported) {
      } else {
        console.log("Don't know how to open URI: " + this.props.url);
  render() {
    return (
      <TouchableOpacity onPress={this.handleClick}>
        {" "}
        <View style={styles.button}>
          {" "}<Text style={styles.text}>Open {this.props.url}</Text>{" "}
        {" "}

Here's an example you can try on Expo Snack:

import React, { Component } from 'react';
import { View, StyleSheet, Button, Linking } from 'react-native';
import { Constants } from 'expo';

export default class App extends Component {
  render() {
    return (
      <View style={styles.container}>
       <Button title="Click me" onPress={ ()=>{ Linking.openURL('')}} />

const styles = StyleSheet.create({
  container: {
    flex: 1,
    alignItems: 'center',
    justifyContent: 'center',
    paddingTop: Constants.statusBarHeight,
    backgroundColor: '#ecf0f1',

Nested routes with react router v4 / v5

Some thing like this.

import React from 'react';_x000D_
import {_x000D_
  BrowserRouter as Router, Route, NavLink, Switch, Link_x000D_
} from 'react-router-dom';_x000D_
import '../assets/styles/App.css';_x000D_
const Home = () =>_x000D_
const About = () =>_x000D_
const Help = () =>_x000D_
const AdminHome = () =>_x000D_
const AdminAbout = () =>_x000D_
    <h1>Admin about</h1>_x000D_
const AdminHelp = () =>_x000D_
    <h1>Admin Help</h1>_x000D_
const AdminNavLinks = (props) => (_x000D_
    <h2>Admin Menu</h2>_x000D_
    <NavLink exact to="/admin">Admin Home</NavLink>_x000D_
    <NavLink to="/admin/help">Admin Help</NavLink>_x000D_
    <NavLink to="/admin/about">Admin About</NavLink>_x000D_
    <Link to="/">Home</Link>_x000D_
const NormalNavLinks = (props) => (_x000D_
    <h2>Normal Menu</h2>_x000D_
    <NavLink exact to="/">Home</NavLink>_x000D_
    <NavLink to="/help">Help</NavLink>_x000D_
    <NavLink to="/about">About</NavLink>_x000D_
    <Link to="/admin">Admin</Link>_x000D_
const App = () => (_x000D_
        <Route exact path="/" component={Home}/>_x000D_
        <Route path="/help" component={Help}/>_x000D_
        <Route path="/about" component={About}/>_x000D_
        <Route exact path="/admin" component={AdminHome}/>_x000D_
        <Route path="/admin/help" component={AdminHelp}/>_x000D_
        <Route path="/admin/about" component={AdminAbout}/>_x000D_
export default App;

Sum of two input value by jquery

Because at least one value is a string the + operator is being interpreted as a string concatenation operator. The simplest fix for this is to indicate that you intend for the values to be interpreted as numbers.

var total = +a + +b;


$('#total_price').val(+a + +b);

Or, better, just pull them out as numbers to begin with:

var a = +$('input[name=service_price]').val();
var b = +$('input[name=modem_price]').val();
var total = a+b;

See Mozilla's Unary + documentation.

Note that this is only a good idea if you know the value is going to be a number anyway. If this is user input you must be more careful and probably want to use parseInt and other validation as other answers suggest.

What is the memory consumption of an object in Java?

It appears that every object has an overhead of 16 bytes on 32-bit systems (and 24-byte on 64-bit systems). is a good source of information. One example among many good ones is the following.

enter image description here is also very informative, for example:

enter image description here

How do I send a POST request as a JSON?

This one works fine for me with apis

import requests

data={'Id':id ,'name': name}
r = url = 'https://apiurllink', data = data)

Angular/RxJs When should I unsubscribe from `Subscription`

in SPA application at ngOnDestroy function (angular lifeCycle) For each subscribe you need to unsubscribe it. advantage => to prevent the state from becoming too heavy.

for example: in component1 :

import {UserService} from './user.service';

private user = {name: 'test', id: 1}

constructor(public userService: UserService) {;

in service:

import {BehaviorSubject} from 'rxjs/BehaviorSubject';

public onUserChange: BehaviorSubject<any> = new BehaviorSubject({});

in component2:

import {Subscription} from 'rxjs/Subscription';
import {UserService} from './user.service';

private onUserChange: Subscription;

constructor(public userService: UserService) {
    this.onUserChange = this.userService.onUserChange.subscribe(user => {

public ngOnDestroy(): void {
    // note: Here you have to be sure to unsubscribe to the subscribe item!

Location Services not working in iOS 8

        // ** Don't forget to add NSLocationWhenInUseUsageDescription in MyApp-Info.plist and give it a string

        self.locationManager = [[CLLocationManager alloc] init];
        self.locationManager.delegate = self;
        // Check for iOS 8. Without this guard the code will crash with "unknown selector" on iOS 7.
        if ([self.locationManager respondsToSelector:@selector(requestWhenInUseAuthorization)]) {
            [self.locationManager requestWhenInUseAuthorization];
        [self.locationManager startUpdatingLocation];

    // Location Manager Delegate Methods    
    - (void)locationManager:(CLLocationManager *)manager didUpdateLocations:(NSArray *)locations
        NSLog(@"%@", [locations lastObject]);


MAC addresses in JavaScript

If this is for an intranet application and all of the clients use DHCP, you can query the DHCP server for the MAC address for a given IP address.

Is it possible to clone html element objects in JavaScript / JQuery?

Using your code you can do something like this in plain JavaScript using the cloneNode() method:

// Create a clone of element with id ddl_1:
let clone = document.querySelector('#ddl_1').cloneNode( true );

// Change the id attribute of the newly created element:
clone.setAttribute( 'id', newId );

// Append the newly created element on element p 
document.querySelector('p').appendChild( clone );

Or using jQuery clone() method (not the most efficient):

$('#ddl_1').clone().attr('id', newId).appendTo('p'); // append to where you want

Jquery array.push() not working

Your HTML should include quotes for attributes :

Not required when using a HTML5 doctype - thanks @bazmegakapa

You create the array each time and add a value to it ... its working as expected ?

Moving the array outside of the live() function works fine :

var myarray = []; // more efficient than new Array()
$("#test").live("click",function() {

Also note that in later versions of jQuery v1.7 -> the live() method is deprecated and replaced by the on() method.

MySQL - Operand should contain 1 column(s)

This error can also occur if you accidentally miss if function name.

for example:

set v_filter_value = 100;

    f_id = 5
    and (v_filter_value <> 0, f_sale_value = v_filter_value, true);

Got this problem when I missed putting if in the if function!

TSQL Pivot without aggregate function

yes, but why !!??

   Select CustomerID,
     Min(Case DBColumnName When 'FirstName' Then Data End) FirstName,
     Min(Case DBColumnName When 'MiddleName' Then Data End) MiddleName,
     Min(Case DBColumnName When 'LastName' Then Data End) LastName,
     Min(Case DBColumnName When 'Date' Then Data End) Date
   From table
   Group By CustomerId

What are allowed characters in cookies?

In ASP.Net you can use System.Web.HttpUtility to safely encode the cookie value before writing to the cookie and convert it back to its original form on reading it out.

// Encode

// Decode

This will stop ampersands and equals signs spliting a value into a bunch of name/value pairs as it is written to a cookie.

How can I read a text file in Android?

Shortest form for small text files (in Kotlin):

val reader = FileReader(path)
val txt = reader.readText()

HttpRequest maximum allowable size in tomcat?

You have to modify two possible limits:

In conf\server.xml

<Connector port="80" protocol="HTTP/1.1"
                maxPostSize="67589953" />

In webapps\manager\WEB-INF\web.xml

  <!-- 52MB max -->

ReferenceError: $ is not defined

i was facing the same problem in the wp-admin section of the site. I enqueued the underscore script cdn and it fixed the problem.

function kk_admin_scripts() {
    wp_enqueue_script('underscore', '//' );
add_action( 'admin_enqueue_scripts', 'kk_admin_scripts' );

How to select a directory and store the location using tkinter in Python

This code may be helpful for you.

from tkinter import filedialog
from tkinter import *
root = Tk()
folder_selected = filedialog.askdirectory()

Short rot13 function - Python

From the builtin module (import this):

s = "foobar"

d = {}
for c in (65, 97):
    for i in range(26):
        d[chr(i+c)] = chr((i+13) % 26 + c)

print("".join([d.get(c, c) for c in s]))  # sbbone

How to use store and use session variables across pages?

Sessions Step By Step

  1. Defining session before everything, No output should be before that, NO OUTPUT

  2. Set your session inside a page and then you have access in that page. For example this is page 1.php

       //This is page 1 and then we will use session that defined from this page:
        $_SESSION['email']='[email protected]';
  3. Using and Getting session in 2.php

    //In this page I am going to use session:
      echo 'Your Email Is Here!  :) ';

NOTE: Comments don't have output.

Separators for Navigation

The other solution are OK, but there is no need to add separator at the very last if using :after or at the very beginning if using :before.


case :after

.link:after {
  content: '|';
  padding: 0 1rem;

.link:last-child:after {
  content: '';

case :before

.link:before {
  content: '|';
  padding: 0 1rem;

.link:first-child:before {
  content: '';

Get file content from URL?

$url = "https://chart.googleapis....";
$json = file_get_contents($url);

Now you can either echo the $json variable, if you just want to display the output, or you can decode it, and do something with it, like so:

$data = json_decode($json);

A simple explanation of Naive Bayes Classification

Naive Bayes: Naive Bayes comes under supervising machine learning which used to make classifications of data sets. It is used to predict things based on its prior knowledge and independence assumptions.

They call it naive because it’s assumptions (it assumes that all of the features in the dataset are equally important and independent) are really optimistic and rarely true in most real-world applications.

It is classification algorithm which makes the decision for the unknown data set. It is based on Bayes Theorem which describe the probability of an event based on its prior knowledge.

Below diagram shows how naive Bayes works

enter image description here

Formula to predict NB:

enter image description here

How to use Naive Bayes Algorithm ?

Let's take an example of how N.B woks

Step 1: First we find out Likelihood of table which shows the probability of yes or no in below diagram. Step 2: Find the posterior probability of each class.

enter image description here

Problem: Find out the possibility of whether the player plays in Rainy condition?

P(Yes|Rainy) = P(Rainy|Yes) * P(Yes) / P(Rainy)

P(Rainy|Yes) = 2/9 = 0.222
P(Yes) = 9/14 = 0.64
P(Rainy) = 5/14 = 0.36

Now, P(Yes|Rainy) = 0.222*0.64/0.36 = 0.39 which is lower probability which means chances of the match played is low.

For more reference refer these blog.

Refer GitHub Repository Naive-Bayes-Examples

Why is the gets function so dangerous that it should not be used?

Why is gets() dangerous

The first internet worm (the Morris Internet Worm) escaped about 30 years ago (1988-11-02), and it used gets() and a buffer overflow as one of its methods of propagating from system to system. The basic problem is that the function doesn't know how big the buffer is, so it continues reading until it finds a newline or encounters EOF, and may overflow the bounds of the buffer it was given.

You should forget you ever heard that gets() existed.

The C11 standard ISO/IEC 9899:2011 eliminated gets() as a standard function, which is A Good Thing™ (it was formally marked as 'obsolescent' and 'deprecated' in ISO/IEC 9899:1999/Cor.3:2007 — Technical Corrigendum 3 for C99, and then removed in C11). Sadly, it will remain in libraries for many years (meaning 'decades') for reasons of backwards compatibility. If it were up to me, the implementation of gets() would become:

char *gets(char *buffer)
    assert(buffer != 0);
    return 0;

Given that your code will crash anyway, sooner or later, it is better to head the trouble off sooner rather than later. I'd be prepared to add an error message:

fputs("obsolete and dangerous function gets() called\n", stderr);

Modern versions of the Linux compilation system generates warnings if you link gets() — and also for some other functions that also have security problems (mktemp(), …).

Alternatives to gets()


As everyone else said, the canonical alternative to gets() is fgets() specifying stdin as the file stream.

char buffer[BUFSIZ];

while (fgets(buffer, sizeof(buffer), stdin) != 0)
    ...process line of data...

What no-one else yet mentioned is that gets() does not include the newline but fgets() does. So, you might need to use a wrapper around fgets() that deletes the newline:

char *fgets_wrapper(char *buffer, size_t buflen, FILE *fp)
    if (fgets(buffer, buflen, fp) != 0)
        size_t len = strlen(buffer);
        if (len > 0 && buffer[len-1] == '\n')
            buffer[len-1] = '\0';
        return buffer;
    return 0;

Or, better:

char *fgets_wrapper(char *buffer, size_t buflen, FILE *fp)
    if (fgets(buffer, buflen, fp) != 0)
        buffer[strcspn(buffer, "\n")] = '\0';
        return buffer;
    return 0;

Also, as caf points out in a comment and paxdiablo shows in his answer, with fgets() you might have data left over on a line. My wrapper code leaves that data to be read next time; you can readily modify it to gobble the rest of the line of data if you prefer:

        if (len > 0 && buffer[len-1] == '\n')
            buffer[len-1] = '\0';
             int ch;
             while ((ch = getc(fp)) != EOF && ch != '\n')

The residual problem is how to report the three different result states — EOF or error, line read and not truncated, and partial line read but data was truncated.

This problem doesn't arise with gets() because it doesn't know where your buffer ends and merrily tramples beyond the end, wreaking havoc on your beautifully tended memory layout, often messing up the return stack (a Stack Overflow) if the buffer is allocated on the stack, or trampling over the control information if the buffer is dynamically allocated, or copying data over other precious global (or module) variables if the buffer is statically allocated. None of these is a good idea — they epitomize the phrase 'undefined behaviour`.

There is also the TR 24731-1 (Technical Report from the C Standard Committee) which provides safer alternatives to a variety of functions, including gets():

§ The gets_s function


#define __STDC_WANT_LIB_EXT1__ 1
#include <stdio.h>
char *gets_s(char *s, rsize_t n);


s shall not be a null pointer. n shall neither be equal to zero nor be greater than RSIZE_MAX. A new-line character, end-of-file, or read error shall occur within reading n-1 characters from stdin.25)

3 If there is a runtime-constraint violation, s[0] is set to the null character, and characters are read and discarded from stdin until a new-line character is read, or end-of-file or a read error occurs.


4 The gets_s function reads at most one less than the number of characters specified by n from the stream pointed to by stdin, into the array pointed to by s. No additional characters are read after a new-line character (which is discarded) or after end-of-file. The discarded new-line character does not count towards number of characters read. A null character is written immediately after the last character read into the array.

5 If end-of-file is encountered and no characters have been read into the array, or if a read error occurs during the operation, then s[0] is set to the null character, and the other elements of s take unspecified values.

Recommended practice

6 The fgets function allows properly-written programs to safely process input lines too long to store in the result array. In general this requires that callers of fgets pay attention to the presence or absence of a new-line character in the result array. Consider using fgets (along with any needed processing based on new-line characters) instead of gets_s.

25) The gets_s function, unlike gets, makes it a runtime-constraint violation for a line of input to overflow the buffer to store it. Unlike fgets, gets_s maintains a one-to-one relationship between input lines and successful calls to gets_s. Programs that use gets expect such a relationship.

The Microsoft Visual Studio compilers implement an approximation to the TR 24731-1 standard, but there are differences between the signatures implemented by Microsoft and those in the TR.

The C11 standard, ISO/IEC 9899-2011, includes TR24731 in Annex K as an optional part of the library. Unfortunately, it is seldom implemented on Unix-like systems.

getline() — POSIX

POSIX 2008 also provides a safe alternative to gets() called getline(). It allocates space for the line dynamically, so you end up needing to free it. It removes the limitation on line length, therefore. It also returns the length of the data that was read, or -1 (and not EOF!), which means that null bytes in the input can be handled reliably. There is also a 'choose your own single-character delimiter' variation called getdelim(); this can be useful if you are dealing with the output from find -print0 where the ends of the file names are marked with an ASCII NUL '\0' character, for example.

Convert all data frame character columns to factors

I noticed "[" indexing columns fails to create levels when iterating:

for ( a_feature in {
feature.df[a_feature] <- factor(feature.df[a_feature]) }

It creates, e.g. for the "Status" column:

Status : Factor w/ 1 level "c(\"Success\", \"Fail\")" : NA NA NA ...

Which is remedied by using "[[" indexing:

for ( a_feature in {
feature.df[[a_feature]] <- factor(feature.df[[a_feature]]) }

Giving instead, as desired:

. Status : Factor w/ 2 levels "Success", "Fail" : 1 1 2 1 ...

html5 audio player - jquery toggle click play/pause?

Simple Add this Code

        var status = "play"; // Declare global variable

        if (status == 'pause') {
        } else {
            status = 'pause';     

How can I analyze a heap dump in IntelliJ? (memory leak)

You can also use VisualVM Launcher to launch VisualVM from within IDEA. I personally find this more convenient.

pypi UserWarning: Unknown distribution option: 'install_requires'

As far as I can tell, this is a bug in setuptools where it isn't removing the setuptools specific options before calling up to the base class in the standard library:

If you have an unconditional import setuptools in your (as you should if using the setuptools specific options), then the fact the script isn't failing with ImportError indicates that setuptools is properly installed.

You can silence the warning as follows:

python -W ignore::UserWarning:distutils.dist <any-other-args>

Only do this if you use the unconditional import that will fail completely if setuptools isn't installed :)

(I'm seeing this same behaviour in a checkout from the post-merger setuptools repo, which is why I'm confident it's a setuptools bug rather than a system config problem. I expect pre-merge distribute would have the same problem)

Java word count program

You can use this code.It may help you:

public static void main (String[] args)

   System.out.println("Simple Java Word Count Program");

   String str1 = "Today is Holdiay Day";
   int count=0;
   String[] wCount=str1.split(" ");

   for(int i=0;i<wCount.length;i++){

How can I check if a checkbox is checked?

    if (document.getElementById('remember').checked) {
    else {
        alert("You didn't check it! Let me check it for you.");

Unable to Install Any Package in Visual Studio 2015

In my case, This problem was caused by a mismatch in my Target framework setting under each project. When I created a new project, VS 2015 defaulted to 4.5.2, however all my nuget packages were built for 4.6.

For some reason, VS 2015 was not showing me these errors. I didn't see them until I created a new empty project and tried to add my nuget project there. This behavior may have been aggravated because I had renamed the project a few times during the initial setup.

I solved the problem by

  • changing the Target Framework on my projects to 4.6
  • closed VS 2015
  • deleted "packages", "obj" and "bin" folders
  • re-open the solution and try to add the nuget package again.

Date ticks and rotation in matplotlib

Another way to applyhorizontalalignment and rotation to each tick label is doing a for loop over the tick labels you want to change:

import numpy as np
import matplotlib.pyplot as plt
import datetime as dt

now =
hours = [now + dt.timedelta(minutes=x) for x in range(0,24*60,10)]
days = [now + dt.timedelta(days=x) for x in np.arange(0,30,1/4.)]
hours_value = np.random.random(len(hours))
days_value = np.random.random(len(days))

fig, axs = plt.subplots(2)

for label in axs[0].get_xmajorticklabels() + axs[1].get_xmajorticklabels():

enter image description here

And here is an example if you want to control the location of major and minor ticks:

import numpy as np
import matplotlib.pyplot as plt
import datetime as dt

fig, axs = plt.subplots(2)
now =
hours = [now + dt.timedelta(minutes=x) for x in range(0,24*60,10)]
days = [now + dt.timedelta(days=x) for x in np.arange(0,30,1/4.)]

x_major_lct = mpl.dates.AutoDateLocator(minticks=2,maxticks=10, interval_multiples=True)
x_minor_lct = matplotlib.dates.HourLocator(byhour = range(0,25,1))
x_fmt = matplotlib.dates.AutoDateFormatter(x_major_lct)
axs[0].set_xlabel("minor ticks set to every hour, major ticks start with 00:00")

x_major_lct = mpl.dates.AutoDateLocator(minticks=2,maxticks=10, interval_multiples=True)
x_minor_lct = matplotlib.dates.DayLocator(bymonthday = range(0,32,1))
x_fmt = matplotlib.dates.AutoDateFormatter(x_major_lct)
axs[1].set_xlabel("minor ticks set to every day, major ticks show first day of month")
for label in axs[0].get_xmajorticklabels() + axs[1].get_xmajorticklabels():

enter image description here

@viewChild not working - cannot read property nativeElement of undefined

it just simple :import this directory

import {Component, Directive, Input, ViewChild} from '@angular/core';

How to delete the first row of a dataframe in R?

Keep the labels from your original file like this:

df = read.table('data.txt', header = T)

If you have columns named x and y, you can address them like this:


If you'd like to actually delete the first row from a data.frame, you can use negative indices like this:

df = df[-1,]

If you'd like to delete a column from a data.frame, you can assign NULL to it:

df$x = NULL

Here are some simple examples of how to create and manipulate a data.frame in R:

# create a data.frame with 10 rows
> x = rnorm(10)
> y = runif(10)
> df = data.frame( x, y )

# write it to a file
> write.table( df, 'test.txt', row.names = F, quote = F )

# read a data.frame from a file: 
> read.table( df, 'test.txt', header = T )

> df$x
 [1] -0.95343778 -0.63098637 -1.30646529  1.38906143  0.51703237 -0.02246754
 [7]  0.20583548  0.21530721  0.69087460  2.30610998
> df$y
 [1] 0.66658148 0.15355851 0.60098886 0.14284576 0.20408723 0.58271061
 [7] 0.05170994 0.83627336 0.76713317 0.95052671

> df$x = x
> df
            y           x
1  0.66658148 -0.95343778
2  0.15355851 -0.63098637
3  0.60098886 -1.30646529
4  0.14284576  1.38906143
5  0.20408723  0.51703237
6  0.58271061 -0.02246754
7  0.05170994  0.20583548
8  0.83627336  0.21530721
9  0.76713317  0.69087460
10 0.95052671  2.30610998

> df[-1,]
            y           x
2  0.15355851 -0.63098637
3  0.60098886 -1.30646529
4  0.14284576  1.38906143
5  0.20408723  0.51703237
6  0.58271061 -0.02246754
7  0.05170994  0.20583548
8  0.83627336  0.21530721
9  0.76713317  0.69087460
10 0.95052671  2.30610998

> df$x = NULL
> df 
1  0.66658148
2  0.15355851
3  0.60098886
4  0.14284576
5  0.20408723
6  0.58271061
7  0.05170994
8  0.83627336
9  0.76713317
10 0.95052671

How to get current formatted date dd/mm/yyyy in Javascript and append it to an input

To get current date/time in javascript:

var date = new Date();

If you need milliseconds for easy server-side interpretation use

var value = date.getTime();

For formatting dates into a user readable string see this

Then just write to hidden field:

document.getElementById("DATE").value = value;

is there something like isset of php in javascript/jQuery?

typeof will serve the purpose I think

if(typeof foo != "undefined"){}

NuGet Packages are missing

Not sure if this will help anyone, but I had this issue come up when I deleted the source code from my local machine without having ever saved the solution file to TFS. (During initial development, I was right-clicking and checking in the project in Solution Explorer, but forgot to ever check in the solution itself.) When I needed to work on this again, all I had in TFS was the .csproj file, no .sln file. So in VS I did a File --> Source Control --> Advanced -- Open from Server and opened the .csproj file. From there I did a Save All and it asked me where I wanted to save the .sln file. I was saving this .sln file to the project directory with the other folders (App_Data, App_Start, etc.), not the top level directory. I finally figured out that I need to save the .sln file up a directory from the project folder so it's on the same level as the project folder. All my paths resolved and I was able to build it again.

List append() in for loop

The list.append function does not return any value(but None), it just adds the value to the list you are using to call that method.

In the first loop round you will assign None (because the no-return of append) to a, then in the second round it will try to call a.append, as a is None it will raise the Exception you are seeing

You just need to change it to:

for i in range(5):    
# [0, 1, 2, 3, 4]

list.append is what is called a mutating or destructive method, i.e. it will destroy or mutate the previous object into a new one(or a new state).

If you would like to create a new list based in one list without destroying or mutating it you can do something like this:

a=['a', 'b', 'c']
result = a + ['d']

print result
# ['a', 'b', 'c', 'd']

print a
# ['a', 'b', 'c']

As a corollary only, you can mimic the append method by doing the following:

a=['a', 'b', 'c']
a = a + ['d']

print a
# ['a', 'b', 'c', 'd']

Python concatenate text files

def concatFiles():
    path = 'input/'
    files = os.listdir(path)
    for idx, infile in enumerate(files):
        print ("File #" + str(idx) + "  " + infile)
    concat = ''.join([open(path + f).read() for f in files])
    with open("output_concatFile.txt", "w") as fo:
        fo.write(path + concat)

if __name__ == "__main__":

How can I access and process nested objects, arrays or JSON?

Objects and arrays has a lot of built-in methods that can help you with processing data.

Note: in many of the examples I'm using arrow functions. They are similar to function expressions, but they bind the this value lexically.

Object.keys(), Object.values() (ES 2017) and Object.entries() (ES 2017)

Object.keys() returns an array of object's keys, Object.values() returns an array of object's values, and Object.entries() returns an array of object's keys and corresponding values in a format [key, value].

const obj = {_x000D_
  a: 1_x000D_
 ,b: 2_x000D_
 ,c: 3_x000D_
console.log(Object.keys(obj)) // ['a', 'b', 'c']_x000D_
console.log(Object.values(obj)) // [1, 2, 3]_x000D_
console.log(Object.entries(obj)) // [['a', 1], ['b', 2], ['c', 3]]

Object.entries() with a for-of loop and destructuring assignment

const obj = {_x000D_
  a: 1_x000D_
 ,b: 2_x000D_
 ,c: 3_x000D_
for (const [key, value] of Object.entries(obj)) {_x000D_
  console.log(`key: ${key}, value: ${value}`)_x000D_

It's very convenient to iterate the result of Object.entries() with a for-of loop and destructuring assignment.

For-of loop lets you iterate array elements. The syntax is for (const element of array) (we can replace const with var or let, but it's better to use const if we don't intend to modify element).

Destructuring assignment lets you extract values from an array or an object and assign them to variables. In this case const [key, value] means that instead of assigning the [key, value] array to element, we assign the first element of that array to key and the second element to value. It is equivalent to this:

for (const element of Object.entries(obj)) {
  const key = element[0]
       ,value = element[1]

As you can see, destructuring makes this a lot simpler.

Array.prototype.every() and Array.prototype.some()

The every() method returns true if the specified callback function returns true for every element of the array. The some() method returns true if the specified callback function returns true for some (at least one) element.

const arr = [1, 2, 3]_x000D_
// true, because every element is greater than 0_x000D_
console.log(arr.every(x => x > 0))_x000D_
// false, because 3^2 is greater than 5_x000D_
console.log(arr.every(x => Math.pow(x, 2) < 5))_x000D_
// true, because 2 is even (the remainder from dividing by 2 is 0)_x000D_
console.log(arr.some(x => x % 2 === 0))_x000D_
// false, because none of the elements is equal to 5_x000D_
console.log(arr.some(x => x === 5))

Array.prototype.find() and Array.prototype.filter()

The find() methods returns the first element which satisfies the provided callback function. The filter() method returns an array of all elements which satisfies the provided callback function.

const arr = [1, 2, 3]_x000D_
// 2, because 2^2 !== 2_x000D_
console.log(arr.find(x => x !== Math.pow(x, 2)))_x000D_
// 1, because it's the first element_x000D_
console.log(arr.find(x => true))_x000D_
// undefined, because none of the elements equals 7_x000D_
console.log(arr.find(x => x === 7))_x000D_
// [2, 3], because these elements are greater than 1_x000D_
console.log(arr.filter(x => x > 1))_x000D_
// [1, 2, 3], because the function returns true for all elements_x000D_
console.log(arr.filter(x => true))_x000D_
// [], because none of the elements equals neither 6 nor 7_x000D_
console.log(arr.filter(x => x === 6 || x === 7))

The map() method returns an array with the results of calling a provided callback function on the array elements.

const arr = [1, 2, 3]_x000D_
console.log( => x + 1)) // [2, 3, 4]_x000D_
console.log( => String.fromCharCode(96 + x))) // ['a', 'b', 'c']_x000D_
console.log( => x)) // [1, 2, 3] (no-op)_x000D_
console.log( => Math.pow(x, 2))) // [1, 4, 9]_x000D_
console.log( // ['1', '2', '3']


The reduce() method reduces an array to a single value by calling the provided callback function with two elements.

const arr = [1, 2, 3]_x000D_
// Sum of array elements._x000D_
console.log(arr.reduce((a, b) => a + b)) // 6_x000D_
// The largest number in the array._x000D_
console.log(arr.reduce((a, b) => a > b ? a : b)) // 3

The reduce() method takes an optional second parameter, which is the initial value. This is useful when the array on which you call reduce() can has zero or one elements. For example, if we wanted to create a function sum() which takes an array as an argument and returns the sum of all elements, we could write it like that:

const sum = arr => arr.reduce((a, b) => a + b, 0)_x000D_
console.log(sum([]))     // 0_x000D_
console.log(sum([4]))    // 4_x000D_
console.log(sum([2, 5])) // 7

How can I find whitespace in a String?

public static void main(String[] args) {
    System.out.println("test word".contains(" "));


Actually they are the same. LEFT OUTER JOIN is same as LEFT JOIN and RIGHT OUTER JOIN is same as RIGHT JOIN. It is more informative way to compare from INNER Join.

See this Wikipedia article for details.

What is the purpose of XSD files?

Before understanding the XSD(XML Schema Definition) let me explain;

What is schema?

for example; emailID: peter#gmail

You can identify the above emailID is not valid because there is no @, .com or .net or .org.

We know the email schema it looks like [email protected].

Conclusion: Schema does not validate the data, It does the validation of structure.

XSD is actually one of the implementation of XML Schema. others we have

We use XSD to validate XML data.

How can I convert a hex string to a byte array?

Here's a nice fun LINQ example.

public static byte[] StringToByteArray(string hex) {
    return Enumerable.Range(0, hex.Length)
                     .Where(x => x % 2 == 0)
                     .Select(x => Convert.ToByte(hex.Substring(x, 2), 16))

How do I undo 'git add' before commit?

If you type:

git status

Git will tell you what is staged, etc., including instructions on how to unstage:

use "git reset HEAD <file>..." to unstage

I find Git does a pretty good job of nudging me to do the right thing in situations like this.

Note: Recent Git versions (1.8.4.x) have changed this message:

(use "git rm --cached <file>..." to unstage)

What good technology podcasts are out there?

Not a technology podcast, but I really have to mention FreelanceRadio. A really great and sometimes hilarious resource. I'm listening to them in the morning, on the way to work. And sometimes feel really stupid just giggling by myself :P

Where can I find my Facebook application id and secret key?

From 2018:

Go to Settings -> Basic -> App Secret (type your password and you're ready to go).

What is an idempotent operation?

An idempotent operation can be repeated an arbitrary number of times and the result will be the same as if it had been done only once. In arithmetic, adding zero to a number is idempotent.

Idempotence is talked about a lot in the context of "RESTful" web services. REST seeks to maximally leverage HTTP to give programs access to web content, and is usually set in contrast to SOAP-based web services, which just tunnel remote procedure call style services inside HTTP requests and responses.

REST organizes a web application into "resources" (like a Twitter user, or a Flickr image) and then uses the HTTP verbs of POST, PUT, GET, and DELETE to create, update, read, and delete those resources.

Idempotence plays an important role in REST. If you GET a representation of a REST resource (eg, GET a jpeg image from Flickr), and the operation fails, you can just repeat the GET again and again until the operation succeeds. To the web service, it doesn't matter how many times the image is gotten. Likewise, if you use a RESTful web service to update your Twitter account information, you can PUT the new information as many times as it takes in order to get confirmation from the web service. PUT-ing it a thousand times is the same as PUT-ing it once. Similarly DELETE-ing a REST resource a thousand times is the same as deleting it once. Idempotence thus makes it a lot easier to construct a web service that's resilient to communication errors.

Further reading: RESTful Web Services, by Richardson and Ruby (idempotence is discussed on page 103-104), and Roy Fielding's PhD dissertation on REST. Fielding was one of the authors of HTTP 1.1, RFC-2616, which talks about idempotence in section 9.1.2.

Convert command line arguments into an array in Bash

Actually your command line arguments are practically like an array already. At least, you can treat the $@ variable much like an array. That said, you can convert it into an actual array like this:

myArray=( "$@" )

If you just want to type some arguments and feed them into the $@ value, use set:

$ set -- apple banana "kiwi fruit"
$ echo "$#"
$ echo "$@"
apple banana kiwi fruit

Understanding how to use the argument structure is particularly useful in POSIX sh, which has nothing else like an array.

Check if a variable exists in a list in Bash

Matvey is right, but you should quote $x and consider any kind of "spaces" (e.g. new line) with

[[ $list =~ (^|[[:space:]])"$x"($|[[:space:]]) ]] && echo 'yes' || echo 'no' 

so, i.e.

# list_include_item "10 11 12" "2"
function list_include_item {
  local list="$1"
  local item="$2"
  if [[ $list =~ (^|[[:space:]])"$item"($|[[:space:]]) ]] ; then
    # yes, list include item
  return $result

end then

`list_include_item "10 11 12" "12"`  && echo "yes" || echo "no"


if `list_include_item "10 11 12" "1"` ; then
  echo "yes"
  echo "no"

Note that you must use "" in case of variables:

`list_include_item "$my_list" "$my_item"`  && echo "yes" || echo "no"

shared global variables in C

In the header file write it with extern. And at the global scope of one of the c files declare it without extern.

How to read file with space separated values in pandas

If you can't get text parsing to work using the accepted answer (e.g if your text file contains non uniform rows) then it's worth trying with Python's csv library - here's an example using a user defined Dialect:

 import csv

 csv.register_dialect('skip_space', skipinitialspace=True)
 with open(my_file, 'r') as f:
      reader=csv.reader(f , delimiter=' ', dialect='skip_space')
      for item in reader:

How to reset selected file with input tag file type in Angular 2?

I think its simple, use #variable

<input #variable type="file" placeholder="File Name" name="filename" (change)="onChange($event); variable.value='' ">

"variable.value = null" option also available

Turning a Comma Separated string into individual rows

Finally, the wait is over with SQL Server 2016. They have introduced the Split string function, STRING_SPLIT:

select OtherID, cs.Value --SplitData
from yourtable
cross apply STRING_SPLIT (Data, ',') cs

All the other methods to split string like XML, Tally table, while loop, etc.. have been blown away by this STRING_SPLIT function.

Here is an excellent article with performance comparison: Performance Surprises and Assumptions: STRING_SPLIT.

For older versions, using tally table here is one split string function(best possible approach)

CREATE FUNCTION [dbo].[DelimitedSplit8K]
        (@pString VARCHAR(8000), @pDelimiter CHAR(1))
--===== "Inline" CTE Driven "Tally Table" produces values from 0 up to 10,000...
     -- enough to cover NVARCHAR(4000)
  WITH E1(N) AS (
                ),                          --10E+1 or 10 rows
       E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
       E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
 cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
                     -- for both a performance gain and prevention of accidental "overruns"
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
                 SELECT 1 UNION ALL
                 SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
                 SELECT s.N1,
                   FROM cteStart s
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
        Item       = SUBSTRING(@pString, l.N1, l.L1)
   FROM cteLen l

Referred from Tally OH! An Improved SQL 8K “CSV Splitter” Function

android start activity from service

Another thing worth mentioning: while the answer above works just fine when our task is in the background, the only way I could make it work if our task (made of service + some activities) was in the foreground (i.e. one of our activities visible to user) was like this:

    Intent intent = new Intent(storedActivity, MyActivity.class);

I do not know whether ACTION_VIEW or FLAG_ACTIVITY_NEW_TASK are of any actual use here. The key to succeeding was


and of course FLAG_ACTIVITY_REORDER_TO_FRONT for not instantiating the activity again. Best of luck!

Java method to sum any number of ints

Use var args

public long sum(int... numbers){
      if(numbers == null){ return 0L;}
      long result = 0L;
      for(int number: numbers){
         result += number;
      return result;   

java.lang.UnsupportedClassVersionError: Bad version number in .class file?

Did you compile with Eclipse? It uses a different compiler (not javac). That should not result in this error (if everything is configured properly), but you can try to compile it with javac instead.

If that fixed the problem, try to see if Eclipse has some incorrect compiler settings. Specifically have it target Java 5.

Call a Vue.js component method from outside the component

In the end I opted for using Vue's ref directive. This allows a component to be referenced from the parent for direct access.


Have a compenent registered on my parent instance:

var vm = new Vue({
    el: '#app',
    components: { 'my-component': myComponent }

Render the component in template/html with a reference:

<my-component ref="foo"></my-component>

Now, elsewhere I can access the component externally

vm.$; //assuming my component has a doSomething() method

See this fiddle for an example:

(old example using Vue 1:

Can I make a function available in every controller in angular?

AngularJs has "Services" and "Factories" just for problems like yours.These are used to have something global between Controllers, Directives, Other Services or any other angularjs components..You can defined functions, store data, make calculate functions or whatever you want inside Services and use them in AngularJs Components as

angular.module('MyModule', [...])
  .service('MyService', ['$http', function($http){
    return {
       users: [...],
       getUserFriends: function(userId){
          return $http({
            method: 'GET',
            url: '/api/user/friends/' + userId

if you need more

Find More About Why We Need AngularJs Services and Factories

Windows batch: call more than one command in a FOR loop?

SilverSkin and Anders are both correct. You can use parentheses to execute multiple commands. However, you have to make sure that the commands themselves (and their parameters) do not contain parentheses. cmd greedily searches for the first closing parenthesis, instead of handling nested sets of parentheses gracefully. This may cause the rest of the command line to fail to parse, or it may cause some of the parentheses to get passed to the commands (e.g. DEL myfile.txt)).

A workaround for this is to split the body of the loop into a separate function. Note that you probably need to jump around the function body to avoid "falling through" into it.

FOR /r %%X IN (*.txt) DO CALL :loopbody %%X
REM Don't "fall through" to :loopbody.

DEL %1

Animate element transform rotate

Just use CSS transitions:

$(element).css( { transition: "transform 0.5s",
                  transform:  "rotate(" + amount + "deg)" } );

setTimeout( function() { $(element).css( { transition: "none" } ) }, 500 );

As example I set the duration of the animation to 0.5 seconds.

Note the setTimeout to remove the transition css property after the animation is over (500 ms)

For readability I omitted vendor prefixes.

This solution requires browser's transition support off course.

MongoDB query with an 'or' condition

Query objects in Mongo by default AND expressions together. Mongo currently does not include an OR operator for such queries, however there are ways to express such queries.

Use "in" or "where".

Its gonna be something like this:

db.mycollection.find( { $where : function() { 
return ( this.startTime < Now() && this.expireTime > Now() || this.expireTime == null ); } } );

Swapping two variable value without using third variable

In javascript:

function swapInPlace(obj) {
    obj.x ^= obj.y
    obj.y ^= obj.x
    obj.x ^= obj.y

function swap(obj) {
    let temp = obj.x
    obj.x = obj.y
    obj.y = temp

Be aware to execution time of both options.

By run this code i measured it.

swapInPlace({x:1, y:2})
console.timeEnd('swapInPlace') // swapInPlace: 0.056884765625ms

swap({x:3, y:6})
console.timeEnd('swap')        // swap: 0.01416015625ms

As you can see (and as many said), swap in place (xor) take alot time than the other option using temp variable.

jquery function setInterval

This is because you are executing the function not referencing it. You should do:


Saving Excel workbook to constant path with filename from two fields

Ok, at that time got it done with the help of a friend and the code looks like this.

Sub Saving()

Dim part1 As String

Dim part2 As String

part1 = Range("C5").Value

part2 = Range("C8").Value

ActiveWorkbook.SaveAs Filename:= _

"C:\-docs\cmat\Desktop\pieteikumi\" & part1 & " " & part2 & ".xlsm", FileFormat:= _
xlOpenXMLWorkbookMacroEnabled, CreateBackup:=False

End Sub

How do I edit this part (FileFormat:= _ xlOpenXMLWorkbookMacroEnabled) for it to save as Excel 97-2013 Workbook, have tried several variations with no success. Thankyou

Seems, that I found the solution, but my idea is flawed. By doing this FileFormat:= _ xlOpenXMLWorkbook, it drops out a popup saying, the you cannot save this workbook as a file without Macro enabled. So, is this impossible?

System.BadImageFormatException An attempt was made to load a program with an incorrect format

If you use IIS, Go to the Application pool Select the one that your site uses and click Advance Settings Make sure that the Enable 32-Bit Applications is set to True

How to initialize a vector in C++

With the new C++ standard (may need special flags to be enabled on your compiler) you can simply do:

std::vector<int> v { 34,23 };
// or
// std::vector<int> v = { 34,23 };

Or even:

std::vector<int> v(2);
v = { 34,23 };

On compilers that don't support this feature (initializer lists) yet you can emulate this with an array:

int vv[2] = { 12,43 };
std::vector<int> v(&vv[0], &vv[0]+2);

Or, for the case of assignment to an existing vector:

int vv[2] = { 12,43 };
v.assign(&vv[0], &vv[0]+2);

Like James Kanze suggested, it's more robust to have functions that give you the beginning and end of an array:

template <typename T, size_t N>
T* begin(T(&arr)[N]) { return &arr[0]; }
template <typename T, size_t N>
T* end(T(&arr)[N]) { return &arr[0]+N; }

And then you can do this without having to repeat the size all over:

int vv[] = { 12,43 };
std::vector<int> v(begin(vv), end(vv));

How do I find out what is hammering my SQL Server?

You can find some useful query here:

Investigating the Cause of SQL Server High CPU

For me this helped a lot:

SELECT s.session_id,
    r.blocking_session_id 'Blk by',
    r.wait_time / (1000 * 60) 'Wait M',
    r.total_elapsed_time / (1000 * 60) 'Elaps M',
    Substring(st.TEXT,(r.statement_start_offset / 2) + 1,
    ((CASE r.statement_end_offset
THEN Datalength(st.TEXT)
ELSE r.statement_end_offset
END - r.statement_start_offset) / 2) + 1) AS statement_text,
    Coalesce(Quotename(Db_name(st.dbid)) + N'.' + Quotename(Object_schema_name(st.objectid, st.dbid)) + N'.' +
    Quotename(Object_name(st.objectid, st.dbid)), '') AS command_text,
FROM sys.dm_exec_sessions AS s
    JOIN sys.dm_exec_requests AS r
ON r.session_id = s.session_id
    CROSS APPLY sys.Dm_exec_sql_text(r.sql_handle) AS st
WHERE r.session_id != @@SPID
ORDER BY r.cpu_time desc

In the fields of status, wait_type and cpu_time you can find the most cpu consuming task that is running right now.

Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException)

You may need to change the Appication Pool setting "Enable 32bit Applications" to TRUE in IIS7 if you have at least 1 32bit dll\exe in your project.

Is there such a thing as min-font-size and max-font-size?

No, there is no CSS property for minimum or maximum font size. Browsers often have a setting for minimum font size, but that’s under the control of the user, not an author.

You can use @media queries to make some CSS settings depending on things like screen or window width. In such settings, you can e.g. set the font size to a specific small value if the window is very narrow.

org.hibernate.MappingException: Unknown entity

Use below line of code in the case of Spring Boot Application Add in Spring Boot Main Class @EntityScan(basePackageClasses=YourClassName.class)

How to fix the error "Windows SDK version 8.1" was not found?

I installed the 8.1 SDK's version:

It used 1GB (a little more) in the installation.

Update October, 9. There's a https error: the sdksetup link is

"Save link as" should help.

What is the most efficient way to store a list in the Django models?

Using one-to-many relation (FK from Friend to parent class) will make your app more scalable (as you can trivially extend the Friend object with additional attributes beyond the simple name). And thus this is the best way

file_get_contents("php://input") or $HTTP_RAW_POST_DATA, which one is better to get the body of JSON request?

The usual rules should apply for how you send the request. If the request is to retrieve information (e.g. a partial search 'hint' result, or a new page to be displayed, etc...) you can use GET. If the data being sent is part of a request to change something (update a database, delete a record, etc..) then use POST.

Server-side, there's no reason to use the raw input, unless you want to grab the entire post/get data block in a single go. You can retrieve the specific information you want via the _GET/_POST arrays as usual. AJAX libraries such as MooTools/jQuery will handle the hard part of doing the actual AJAX calls and encoding form data into appropriate formats for you.

How to add a new column to an existing sheet and name it?

Use insert method from range, for example

Sub InsertColumn()
        Columns("C:C").Insert Shift:=xlToRight, CopyOrigin:=xlFormatFromLeftOrAbove
        Range("C1").Value = "Loc"
End Sub

Babel 6 regeneratorRuntime is not defined

Update your .babelrc file according to the following examples, it will work.

If you are using @babel/preset-env package

  "presets": [
      "@babel/preset-env", {
        "targets": {
          "node": "current"
or if you are using babel-preset-env package

  "presets": [
      "env", {
        "targets": {
          "node": "current"

ASP.NET MVC Dropdown List From SelectList

Just try this in razor

    var selectList = new SelectList(
        new List<SelectListItem>
            new SelectListItem {Text = "Google", Value = "Google"},
            new SelectListItem {Text = "Other", Value = "Other"},
        }, "Value", "Text");

and then

@Html.DropDownListFor(m => m.YourFieldName, selectList, "Default label", new { @class = "css-class" })


@Html.DropDownList("ddlDropDownList", selectList, "Default label", new { @class = "css-class" })

How do I POST JSON data with cURL?

You can use Postman with its intuitive GUI to assemble your cURL command.

  1. Install and Start Postman
  2. Type in your URL, Post Body, Request Headers etc. pp.
  3. Click on Code
  4. Select cURL from the drop-down list
  5. copy & paste your cURL command

Note: There are several options for automated request generation in the drop-down list, which is why I thought my post was neccessary in the first place.

How to delete Tkinter widgets from a window?

You simply use the destroy() method to delete the specified widgets like this:

lbl = tk.Label(....)

btn = tk.Button(....., command=lambda: lbl.destroy())

Using this you can completely destroy the specific widgets.

How to automate browsing using python?

Internet Explorer specific, but rather good:

The advantage compared to urllib/BeautifulSoup is that it executes Javascript as well since it uses IE.

Using BufferedReader.readLine() in a while loop properly

You're calling br.readLine() a second time inside the loop.
Therefore, you end up reading two lines each time you go around.

Difference between nVidia Quadro and Geforce cards?

Hardware wise the Quadro and GeForce cards are often idential. Indeed it is sometimes possible to convert some models from GeForce into Quadro by simply uploading new firmware and changing a couple resistor jumpers.

The difference is in the intended market and hence cost.

Quadro cards are intended for CAD. High end CAD software still uses OpenGL, whereas games and lower end CAD software use Direct3D (aka DirectX).

Quadro cards simply have firmware that is optimised for OpenGL. In the early days OpenGL was better and faster than Direct3D but now there is little difference. Gaming cards only support a very limited set of OpenGL, hence they don't run it very well.

CAD companies, e.g. Dassault with SolidWorks actively push high end cards by offering no support for DirectX with any level of performance.

Other CAD companies such as Altium, with Altium Designer, made the decision that forcing their customers to buy more expensive cards is not worthwhile when Direct3D is as good (if not better these days) than OpenGL.

Because of the cost, there are often other differences in the hardware, such as less use of overclocking, more memory etc, but these have relatively minor effects compared with the firmware support.

How to redirect output of an entire shell script within the script itself?

You can make the whole script a function like this:

main_function() {

then at the end of the script have this:

if [ -z $TERM ]; then
  # if not run via terminal, log everything into a log file
  main_function 2>&1 >> /var/log/my_uber_script.log
  # run via terminal, only output to screen

Alternatively, you may log everything into logfile each run and still output it to stdout by simply doing:

# log everything, but also output to stdout
main_function 2>&1 | tee -a /var/log/my_uber_script.log

How do I use dataReceived event of the SerialPort Port Object in C#?

First off I recommend you use the following constructor instead of the one you currently use:

new SerialPort("COM10", 115200, Parity.None, 8, StopBits.One);

Next, you really should remove this code:

// Wait 10 Seconds for data...
for (int i = 0; i < 1000; i++)
    Console.WriteLine(sp.Read(buf,0,bufSize)); //prints data directly to the Console

And instead just loop until the user presses a key or something, like so:

namespace serialPortCollection
{   class Program
        static void Main(string[] args)
            SerialPort sp = new SerialPort("COM10", 115200);
            sp.DataReceived += port_OnReceiveDatazz; // Add DataReceived Event Handler

            sp.WriteLine("$"); //Command to start Data Stream


            sp.WriteLine("!"); //Stop Data Stream Command

       // My Event Handler Method
        private static void port_OnReceiveDatazz(object sender, 
                                   SerialDataReceivedEventArgs e)
            SerialPort spL = (SerialPort) sender;
            byte[] buf = new byte[spL.BytesToRead];
            Console.WriteLine("DATA RECEIVED!");
            spL.Read(buf, 0, buf.Length);
            foreach (Byte b in buf)

Also, note the revisions to the data received event handler, it should actually print the buffer now.


I just ran the following code successfully on my machine (using a null modem cable between COM33 and COM34)

namespace TestApp
    class Program
        static void Main(string[] args)
            Thread writeThread = new Thread(new ThreadStart(WriteThread));
            SerialPort sp = new SerialPort("COM33", 115200, Parity.None, 8, StopBits.One);
            sp.DataReceived += port_OnReceiveDatazz; // Add DataReceived Event Handler

            sp.WriteLine("$"); //Command to start Data Stream



            sp.WriteLine("!"); //Stop Data Stream Command

        private static void port_OnReceiveDatazz(object sender, 
                                   SerialDataReceivedEventArgs e)
            SerialPort spL = (SerialPort) sender;
            byte[] buf = new byte[spL.BytesToRead];
            Console.WriteLine("DATA RECEIVED!");
            spL.Read(buf, 0, buf.Length);
            foreach (Byte b in buf)
                Console.Write(b.ToString() + " ");

        private static void WriteThread()
            SerialPort sp2 = new SerialPort("COM34", 115200, Parity.None, 8, StopBits.One);
            byte[] buf = new byte[100];
            for (byte i = 0; i < 100; i++)
                buf[i] = i;
            sp2.Write(buf, 0, buf.Length);


Given all of the traffic on this question recently. I'm beginning to suspect that either your serial port is not configured properly, or that the device is not responding.

I highly recommend you attempt to communicate with the device using some other means (I use hyperterminal frequently). You can then play around with all of these settings (bitrate, parity, data bits, stop bits, flow control) until you find the set that works. The documentation for the device should also specify these settings. Once I figured those out, I would make sure my .NET SerialPort is configured properly to use those settings.

Some tips on configuring the serial port:

Note that when I said you should use the following constructor, I meant that use that function, not necessarily those parameters! You should fill in the parameters for your device, the settings below are common, but may be different for your device.

new SerialPort("COM10", 115200, Parity.None, 8, StopBits.One);

It is also important that you setup the .NET SerialPort to use the same flow control as your device (as other people have stated earlier). You can find more info here:

BigDecimal to string

To archive the necessary result with double constructor you need to round the BigDecimal before convert it to String e.g.

new java.math.BigDecimal(10.0001).round(new java.math.MathContext(6, java.math.RoundingMode.HALF_UP)).toString()

will print the "10.0001"

Session 'app': Error Launching activity

Just disable Instant Run.

Go To File >> Settings >> Build, Execute, Deployment >> Instant Run

Uncheck The Box that says Enable instant run to hot swap code/resource changes on deploy

Re-run the emulator.

SQL JOIN, GROUP BY on three tables to get totals

First of all, shouldn't there be a CustomerId in the Invoices table? As it is, You can't perform this query for Invoices that have no payments on them as yet. If there are no payments on an invoice, that invoice will not even show up in the ouput of the query, even though it's an outer join...

Also, When a customer makes a payment, how do you know what Invoice to attach it to ? If the only way is by the InvoiceId on the stub that arrives with the payment, then you are (perhaps inappropriately) associating Invoices with the customer that paid them, rather than with the customer that ordered them... . (Sometimes an invoice can be paid by someone other than the customer who ordered the services)

Open CSV file via VBA (performance)

Workbooks.Open does work too.

Workbooks.Open ActiveWorkbook.Path & "\Temp.csv", Local:=True

this works/is needed because i use Excel in germany and excel does use "," to separate .csv by default because i use an english installation of windows. even if you use the code below excel forces the "," separator.

Workbooks.Open ActiveWorkbook.Path & "\Test.csv", , , 6, , , , , ";"

and Workbooks.Open ActiveWorkbook.Path & "\Temp.csv", , , 4 +variants of this do not work(!)

why do they even have the delimiter parameter if it is blocked by the Local parameter ?! this makes no sense at all. but now it works.

python: NameError:global name '...‘ is not defined

You need to call self.a() to invoke a from b. a is not a global function, it is a method on the class.

You may want to read through the Python tutorial on classes some more to get the finer details down.

Oracle comparing timestamp with date

You can truncate the date part:

select * from table1 where trunc(field1) = to_date('2012-01-01', 'YYYY-MM-DD')

The trouble with this approach is that any index on field1 wouldn't be used due to the function call.

Alternatively (and more index friendly)

select * from table1 
 where field1 >= to_timestamp('2012-01-01', 'YYYY-MM-DD') 
   and field1 < to_timestamp('2012-01-02', 'YYYY-MM-DD')

URL rewriting with PHP

PHP is not what you are looking for, check out mod_rewrite

How can I maintain fragment state when added to the back stack?

first: just use add method instead of replace method of FragmentTransaction class then you have to add secondFragment to stack by addToBackStack method

second :on back click you have to call popBackStackImmediate()

Fragment sourceFragment = new SourceFragment ();
final Fragment secondFragment = new SecondFragment();
final FragmentTransaction ft = getChildFragmentManager().beginTransaction();
ft.add(, secondFragment );
ft.hide(sourceFragment );
((SecondFragment)secondFragment).backFragmentInstanceClick = new SecondFragment.backFragmentNewsResult()
        public void backFragmentNewsResult()

Row Offset in SQL Server

This is one way (SQL2000)

    SELECT TOP (@pageSize) * FROM
        SELECT TOP (@pageNumber * @pageSize) *
        FROM tableName 
        ORDER BY columnName ASC
    ) AS t1 
    ORDER BY columnName DESC
) AS t2 
ORDER BY columnName ASC

and this is another way (SQL 2005)

;WITH results AS (
        rowNo = ROW_NUMBER() OVER( ORDER BY columnName ASC )
        , *
    FROM tableName 
FROM results
WHERE rowNo between (@pageNumber-1)*@pageSize+1 and @pageNumber*@pageSize

Add tooltip to font awesome icon

The issue of adding tooltips to any HTML-Output (not only FontAwesome) is an entire book on its own. ;-)

The default way would be to use the title-attribute:

  <div id="welcomeText" title="So nice to see you!">
    <p>Welcome Harriet</p>


<i class="fa fa-cog" title="Do you like my fa-coq icon?"></i>

But since most people (including me) do not like the standard-tooltips, there are MANY tools out there which will "beautify" them and offer all sort of enhancements. My personal favourites are jBox and qtip2.

How can I draw vertical text with CSS cross-browser?

Updated this answer with recent information (from CSS Tricks). Kudos to Matt and Douglas for pointing out the filter implementation.

.rotate {
  -webkit-transform: rotate(-90deg);
  -moz-transform: rotate(-90deg);
  -ms-transform: rotate(-90deg);
  -o-transform: rotate(-90deg);
  transform: rotate(-90deg);

  /* also accepts left, right, top, bottom coordinates; not required, but a good idea for styling */
  -webkit-transform-origin: 50% 50%;
  -moz-transform-origin: 50% 50%;
  -ms-transform-origin: 50% 50%;
  -o-transform-origin: 50% 50%;
  transform-origin: 50% 50%;

  /* Should be unset in IE9+ I think. */
  filter: progid:DXImageTransform.Microsoft.BasicImage(rotation=3);

Old answer:

For FF 3.5 or Safari/Webkit 3.1, check out: -moz-transform (and -webkit-transform). IE has a Matrix filter(v5.5+), but I'm not certain how to use it. Opera has no transformation capabilities yet.

.rot-neg-90 {
  /* rotate -90 deg, not sure if a negative number is supported so I used 270 */
  -moz-transform: rotate(270deg);
  -moz-transform-origin: 50% 50%;
  -webkit-transform: rotate(270deg);
  -webkit-transform-origin: 50% 50%;
  /* IE support too convoluted for the time I've got on my hands... */

Definitive way to trigger keypress events with jQuery

The real answer has to include keyCode:

var e = jQuery.Event("keydown");
e.which = 50; // # Some key code value
e.keyCode = 50

Even though jQuery's website says that which and keyCode are normalized they are very badly mistaken. It's always safest to do the standard cross-browser checks for e.which and e.keyCode and in this case just define both.

setting content between div tags using javascript

Try the following:


msdn link for detail : innerHTML Property

How can the size of an input text box be defined in HTML?

You could set its width:

<input type="text" id="text" name="text_name" style="width: 300px;" />

or even better define a class:

<input type="text" id="text" name="text_name" class="mytext" />

and in a separate CSS file apply the necessary styling:

.mytext {
    width: 300px;

If you want to limit the number of characters that the user can type into this textbox you could use the maxlength attribute:

<input type="text" id="text" name="text_name" class="mytext" maxlength="25" />

memcpy() vs memmove()

The difference between memcpy and memmove is that

  1. in memmove, the source memory of specified size is copied into buffer and then moved to destination. So if the memory is overlapping, there are no side effects.

  2. in case of memcpy(), there is no extra buffer taken for source memory. The copying is done directly on the memory so that when there is memory overlap, we get unexpected results.

These can be observed by the following code:

//include string.h, stdio.h, stdlib.h
int main(){
  char a[]="hare rama hare rama";

  char b[]="hare rama hare rama";



Output is:

hare hare rama hare rama
hare hare hare hare hare hare rama hare rama

RecyclerView vs. ListView

In my opinion RecyclerView was made to address the problem with the recycle pattern used in listviews because it was making developer's life more difficult. All the other you could handle more or less. For instance I use the same adapter for ListView and GridView it doesn't matter in both views the getView, getItemCount, getTypeCount is used so it's the same. RecyclerView isn't needed if ListView with ListAdapter or GridView with grid adapters is already working for you. If you have implemented correctly the ViewHolder pattern in your listviews then you won't see any big improvement over RecycleView.

How do I concatenate text in a query in sql server?

If you are using SQL Server 2005 (or greater) you might want to consider switching to NVARCHAR(MAX) in your table definition; TEXT, NTEXT, and IMAGE data types of SQL Server 2000 will be deprecated in future versions of SQL Server. SQL Server 2005 provides backward compatibility to data types, but you should probably be using VARCHAR(MAX), NVARCHAR(MAX), and VARBINARY(MAX) instead.

Is there a git-merge --dry-run option?

Undoing a merge with git is so easy you shouldn't even worry about the dry run:

$ git pull $REMOTE $BRANCH
# uh oh, that wasn't right
$ git reset --hard ORIG_HEAD
# all is right with the world

EDIT: As noted in the comments below, if you have changes in your working directory or staging area you'll probably want to stash them before doing the above (otherwise they will disappear following the git reset above)

Sum rows in data.frame or matrix

I came here hoping to find a way to get the sum across all columns in a data table and run into issues implementing the above solutions. A way to add a column with the sum across all columns uses the cbind function:

cbind(data, total = rowSums(data))

This method adds a total column to the data and avoids the alignment issue yielded when trying to sum across ALL columns using the above solutions (see the post below for a discussion of this issue).

Adding a new column to matrix error

Making the iPhone vibrate

I had great trouble with this for devices that had vibration turned off in some manner, but we needed it to work regardless, because it is critical to our application functioning, and since it is just an integer to a documented method call, it will pass validation. So I have tried some sounds that were outside of the well documented ones here: TUNER88/iOSSystemSoundsLibrary

I have then stumbled upon 1352, which is working regardless of the silent switch or the settings on the device (Settings->vibrate on ring, vibrate on silent).

- (void)vibratePhone;
     if([[UIDevice currentDevice].model isEqualToString:@"iPhone"])
         AudioServicesPlaySystemSound (1352); //works ALWAYS as of this post
          // Not an iPhone, so doesn't have vibrate
          // play the less annoying tick noise or one of your own
          AudioServicesPlayAlertSound (1105);

How do I undo the most recent local commits in Git?

If you have Git Extras installed, you can run git undo to undo the latest commit. git undo 3 will undo the last three commits.

Run .php file in Windows Command Prompt (cmd)

You should declare Environment Variable for PHP in path, so you could use like this:

C:\Path\to\somewhere>php cli.php

You can do it like this

annotation to make a private method public only for test classes

As much as I know there is no annotation like this. The best way is to use reflection as some of the others suggested. Look at this post:
How do I test a class that has private methods, fields or inner classes?

You should only watch out on testing the exception outcome of the method. For example: if u expect an IllegalArgumentException, but instead you'll get "null" (Class:java.lang.reflect.InvocationTargetException).
A colegue of mine proposed using the powermock framework for these situations, but I haven't tested it yet, so no idea what exactly it can do. Although I have used the Mockito framework that it is based upon and thats a good framework too (but I think doesn't solve the private method exception issue).

It's a great idea though having the @PublicForTests annotation.


Convert javascript object or array to json for ajax data

You can use JSON.stringify(object) with an object and I just wrote a function that'll recursively convert an array to an object, like this JSON.stringify(convArrToObj(array)), which is the following code (more detail can be found on this answer):

// Convert array to object
var convArrToObj = function(array){
    var thisEleObj = new Object();
    if(typeof array == "object"){
        for(var i in array){
            var thisEle = convArrToObj(array[i]);
            thisEleObj[i] = thisEle;
    }else {
        thisEleObj = array;
    return thisEleObj;

To make it more generic, you can override the JSON.stringify function and you won't have to worry about it again, to do this, just paste this at the top of your page:

// Modify JSON.stringify to allow recursive and single-level arrays
    // Convert array to object
    var convArrToObj = function(array){
        var thisEleObj = new Object();
        if(typeof array == "object"){
            for(var i in array){
                var thisEle = convArrToObj(array[i]);
                thisEleObj[i] = thisEle;
        }else {
            thisEleObj = array;
        return thisEleObj;
    var oldJSONStringify = JSON.stringify;
    JSON.stringify = function(input){
        return oldJSONStringify(convArrToObj(input));

And now JSON.stringify will accept arrays or objects! (link to jsFiddle with example)


Here's another version that's a tad bit more efficient, although it may or may not be less reliable (not sure -- it depends on if JSON.stringify(array) always returns [], which I don't see much reason why it wouldn't, so this function should be better as it does a little less work when you use JSON.stringify with an object):

    // Convert array to object
    var convArrToObj = function(array){
        var thisEleObj = new Object();
        if(typeof array == "object"){
            for(var i in array){
                var thisEle = convArrToObj(array[i]);
                thisEleObj[i] = thisEle;
        }else {
            thisEleObj = array;
        return thisEleObj;
    var oldJSONStringify = JSON.stringify;
    JSON.stringify = function(input){
        if(oldJSONStringify(input) == '[]')
            return oldJSONStringify(convArrToObj(input));
            return oldJSONStringify(input);

jsFiddle with example here

js Performance test here, via jsPerf

How to use Jackson to deserialise an array of objects

From Eugene Tskhovrebov

List<MyClass> myObjects = Arrays.asList(mapper.readValue(json, MyClass[].class))

This solution seems to be the best for me.

How do I add a newline to a windows-forms TextBox?

Try using Environment.NewLine:

Gets the newline string defined for this environment.

Something like this ought to work:

textBox.AppendText("your new text" & Environment.NewLine)

Add or change a value of JSON key with jquery or javascript

It seems if your key is saved in a variable. data.key = value won't work.

You should use data[key] = value


data = {key1:'v1', key2:'v2'};

var mykey = 'key1'; 
data.mykey = 'newv1';
data[mykey] = 'newV2';



  "key1": "newV2",
  "key2": "v2",
  "mykey": "newv1"

How can I read SMS messages from the device programmatically in Android?

From API 19 onwards you can make use of the Telephony Class for that; Since hardcored values won't retrieve messages in every devices because the content provider Uri changes from devices and manufacturers.

public void getAllSms(Context context) {

    ContentResolver cr = context.getContentResolver();
    Cursor c = cr.query(Telephony.Sms.CONTENT_URI, null, null, null, null);
    int totalSMS = 0;
    if (c != null) {
        totalSMS = c.getCount();
        if (c.moveToFirst()) {
            for (int j = 0; j < totalSMS; j++) {
                String smsDate = c.getString(c.getColumnIndexOrThrow(Telephony.Sms.DATE));
                String number = c.getString(c.getColumnIndexOrThrow(Telephony.Sms.ADDRESS));
                String body = c.getString(c.getColumnIndexOrThrow(Telephony.Sms.BODY));
                Date dateFormat= new Date(Long.valueOf(smsDate));
                String type;
                switch (Integer.parseInt(c.getString(c.getColumnIndexOrThrow(Telephony.Sms.TYPE)))) {
                    case Telephony.Sms.MESSAGE_TYPE_INBOX:
                        type = "inbox";
                    case Telephony.Sms.MESSAGE_TYPE_SENT:
                        type = "sent";
                    case Telephony.Sms.MESSAGE_TYPE_OUTBOX:
                        type = "outbox";



    } else {
        Toast.makeText(this, "No message to show!", Toast.LENGTH_SHORT).show();

How do I pass parameters into a PHP script through a webpage?

Presumably you're passing the arguments in on the command line as follows:

php /path/to/wwwpublic/path/to/script.php arg1 arg2

... and then accessing them in the script thusly:

// $argv[0] is '/path/to/wwwpublic/path/to/script.php'
$argument1 = $argv[1];
$argument2 = $argv[2];

What you need to be doing when passing arguments through HTTP (accessing the script over the web) is using the query string and access them through the $_GET superglobal:

Go to

... and access:

$argument1 = $_GET['argument1'];
$argument2 = $_GET['argument2'];

If you want the script to run regardless of where you call it from (command line or from the browser) you'll want something like the following:

EDIT: as pointed out by Cthulhu in the comments, the most direct way to test which environment you're executing in is to use the PHP_SAPI constant. I've updated the code accordingly:

if (PHP_SAPI === 'cli') {
    $argument1 = $argv[1];
    $argument2 = $argv[2];
else {
    $argument1 = $_GET['argument1'];
    $argument2 = $_GET['argument2'];

How do I seed a random class to avoid getting duplicate random values

public static Random rand = new Random(); // this happens once, and will be great at preventing duplicates

Note, this is not to be used for cryptographic purposes.

ImportError: No module named 'google'

I had a similar import problem. I noticed that there was no file in the root of the google package. So, I created an empty and now the import works.

Remove a fixed prefix/suffix from a string in Bash

$ foo=${string#"$prefix"}
$ foo=${foo%"$suffix"}
$ echo "${foo}"

This is documented in the Shell Parameter Expansion section of the manual:


The word is expanded to produce a pattern and matched according to the rules described below (see Pattern Matching). If the pattern matches the beginning of the expanded value of parameter, then the result of the expansion is the expanded value of parameter with the shortest matching pattern (the # case) or the longest matching pattern (the ## case) deleted. […]


The word is expanded to produce a pattern and matched according to the rules described below (see Pattern Matching). If the pattern matches a trailing portion of the expanded value of parameter, then the result of the expansion is the value of parameter with the shortest matching pattern (the % case) or the longest matching pattern (the %% case) deleted. […]

Visual Studio setup problem - 'A problem has been encountered while loading the setup components. Canceling setup.'

I had the same error message. For me it was happening because I was trying to run the installer from the DVD rather than running the installer from Add/Remove programs.

Displaying a webcam feed using OpenCV and Python

If you only have one camera, or you don't care which camera is the correct one, then use "-1" as the index. Ie for your example capture = cv.CaptureFromCAM(-1).

How to find and restore a deleted file in a Git repository

If the deletion has not been committed, the command below will restore the deleted file in the working tree.

$ git checkout -- <file>

You can get a list of all the deleted files in the working tree using the command below.

$ git ls-files --deleted

If the deletion has been committed, find the commit where it happened, then recover the file from this commit.

$ git rev-list -n 1 HEAD -- <file>
$ git checkout <commit>^ -- <file>

In case you are looking for the path of the file to recover, the following command will display a summary of all deleted files.

$ git log --diff-filter=D --summary

Using pointer to char array, values in that array can be accessed?

Your should create ptr as follows:

char *ptr;

You have created ptr as an array of pointers to chars. The above creates a single pointer to a char.

Edit: complete code should be:

char *ptr;
char arr[5] = {'a','b','c','d','e'};
ptr = arr;
printf("\nvalue:%c", *(ptr+0));

Illegal character in path at index 16

the install directory can't have space. reinstall the software will correct it

How to pass the -D System properties while testing on Eclipse?

Yes this is the way:

Right click on your program, select run -> run configuration then on vm argument

-Denv=EnvironmentName -Dcucumber.options="--tags @ifThereisAnyTag"

Then you can apply and close.

How do I manage MongoDB connections in a Node.js web application?

I have implemented below code in my project to implement connection pooling in my code so it will create a minimum connection in my project and reuse available connection

/* Mongo.js*/

var MongoClient = require('mongodb').MongoClient;
var url = "mongodb://localhost:27017/yourdatabasename"; 
var assert = require('assert');

var connection=[];
// Create the database connection
establishConnection = function(callback){

                MongoClient.connect(url, { poolSize: 10 },function(err, db) {
                    assert.equal(null, err);

                        connection = db
                        if(typeof callback === 'function' && callback())




function getconnection(){
    return connection

module.exports = {


// establish one connection with all other routes will use.
var db = require('./routes/mongo')


//you can also call with callback if you wanna create any collection at starting
  conn.createCollection("collectionName", function(err, res) {
    if (err) throw err;
    console.log("Collection created!");

// anyother route.js

var db = require('./mongo')

router.get('/', function(req, res, next) {
    var connection = db.getconnection()


Manually install Gradle and use it in Android Studio

Assume, you have installed the latest gradle once. But, If your particular project gradle version not match with the gradle version that already installed in the machine, the gradle sycn want to download that version. To prevent this download there is one trick. First You have to know the gradle version that already installed in your machine. Go to : C:\Users{username}.gradle\wrapper\dists, here you see the versions allready installed, remember the latest version, assume it is . Now, come back to Android Studio. In your Opened project, navigate Android Studio's project tree, open the file gradle/wrapper/ Change this entry:


This way we prevent downloading the gradle again and again. But avoid this thing, if the version really old. If that, you will find this warning :

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.

bootstrap 3 tabs not working properly

When I moved the following lines from the head section to the end of the body section it worked.

<script src=""></script>
<script src=""></script>

How to check if ping responded or not in a batch file


          # refresh the timestamp before each ping attempt
          theTime=$(date -Iseconds)

          # refresh the ping variable
          ping -n 1

            if [ $? -eq 0 ] 
                 echo $theTime + '| connection is up' >> $logPath
                 echo $theTime + '| connection is down' >> $logPath
            Sleep 1
             echo ' '

Error: request entity too large

In my case the problem was on Nginx configuration. To solve it I have to edit the file: /etc/nginx/nginx.conf and add this line inside server block:

client_max_body_size 5M;

Restart Nginx and the problems its gone

sudo systemctl restart nginx

Target a css class inside another css class

Not certain what the HTML looks like (that would help with answers). If it's

<div class="testimonials content">stuff</div>

then simply remove the space in your css. A la...

.testimonials.content { css here }


Okay, after seeing HTML see if this works...

.testimonials .wrapper .content { css here }

or just

.testimonials .wrapper { css here }


.desc-container .wrapper { css here }

all 3 should work.

Static variable inside of a function in C

The output will be 6 7. A static variable (whether inside a function or not) is initialized exactly once, before any function in that translation unit executes. After that, it retains its value until modified.

How to build PDF file from binary string returned from a web-service using javascript

I saw another question on just this topic recently (streaming pdf into iframe using dataurl only works in chrome).

I've constructed pdfs in the ast and streamed them to the browser. I was creating them first with fdf, then with a pdf class I wrote myself - in each case the pdf was created from data retrieved from a COM object based on a couple of of GET params passed in via the url.

From looking at your data sent recieved in the ajax call, it looks like you're nearly there. I haven't played with the code for a couple of years now and didn't document it as well as I'd have cared to, but - I think all you need to do is set the target of an iframe to be the url you get the pdf from. Though this may not work - the file that oututs the pdf may also have to outut a html response header first.

In a nutshell, this is the output code I used:

//We send to a browser
header('Content-Type: application/pdf');
    $this->Error('Some data has already been output, can\'t send PDF file');
header('Content-Length: '.strlen($this->buffer));
header('Content-Disposition: inline; filename="'.$name.'"');
header('Cache-Control: private, max-age=0, must-revalidate');
header('Pragma: public');
echo $this->buffer;

So, without seeing the full response text fro the ajax call I can't really be certain what it is, though I'm inclined to think that the code that outputs the pdf you're requesting may only be doig the equivalent of the last line in the above code. If it's code you have control over, I'd try setting the headers - then this way the browser can just deal with the response text - you don't have to bother doing a thing to it.

I simply constructed a url for the pdf I wanted (a timetable) then created a string that represented the html for an iframe of the desired sie, id etc that used the constructed url as it's src. As soon as I set the inner html of a div to the constructed html string, the browser asked for the pdf and then displayed it when it was received.

function  showPdfTt(studentId)
    var url, tgt;
    title = byId("popupTitle");
    title.innerHTML = "Timetable for " + studentId;
    tgt = byId("popupContent");
    url = "pdftimetable.php?";
    url += "id="+studentId;
    url += "&type=Student";
    tgt.innerHTML = "<iframe onload=\"centerElem(byId('box'))\" src='"+url+"' width=\"700px\" height=\"500px\"></iframe>";

EDIT: forgot to mention - you can send binary pdf's in this manner. The streams they contain don't need to be ascii85 or hex encoded. I used flate on all the streams in the pdf and it worked fine.

How to vertically center content with variable height within a div?

Using the child selector, I've taken Fadi's incredible answer above and boiled it down to just one CSS rule that I can apply. Now all I have to do is add the contentCentered class name to elements I want to center:

.contentCentered {_x000D_
  text-align: center;_x000D_
.contentCentered::before {_x000D_
  content: '';_x000D_
  display: inline-block;_x000D_
  height: 100%; _x000D_
  vertical-align: middle;_x000D_
  margin-right: -.25em; /* Adjusts for spacing */_x000D_
.contentCentered > * {_x000D_
  display: inline-block;_x000D_
  vertical-align: middle;_x000D_
<div class="contentCentered">_x000D_
    <h1>Some text</h1>_x000D_
    <p>But he stole up to us again, and suddenly clapping his hand on my_x000D_
      shoulder, said&mdash;"Did ye see anything looking like men going_x000D_
      towards that ship a while ago?"</p>_x000D_

Forked CodePen:

Change the background color of CardView programmatically

try it works easy


How to resolve git status "Unmerged paths:"?

Another way of dealing with this situation if your files ARE already checked in, and your files have been merged (but not committed, so the merge conflicts are inserted into the file) is to run:

git reset

This will switch to HEAD, and tell git to forget any merge conflicts, and leave the working directory as is. Then you can edit the files in question (search for the "Updated upstream" notices). Once you've dealt with the conflicts, you can run

git add -p

which will allow you to interactively select which changes you want to add to the index. Once the index looks good (git diff --cached), you can commit, and then

git reset --hard

to destroy all the unwanted changes in your working directory.

How do you do a limit query in JPQL or HQL?

You can easily use pagination for this.

    @QueryHints({ @QueryHint(name = "org.hibernate.cacheable", value = "true") })
    @Query("select * from a_table order by a_table_column desc")
    List<String> getStringValue(Pageable pageable);

you have to pass new PageRequest(0, 1)to fetch records and from the list fetch the first record.

ReferenceError: fetch is not defined

You have to use the isomorphic-fetch module to your Node project because of Node does not contain Fetch API yet. for fixing this problem run below command:

npm install --save isomorphic-fetch es6-promise

After installation use below code in your project:

import "isomorphic-fetch"

Hope this answer helps you.

ORDER BY using Criteria API

You can add join type as well:

Criteria c2 = c.createCriteria("mother", "mother", CriteriaSpecification.LEFT_JOIN);
Criteria c3 = c2.createCriteria("kind", "kind", CriteriaSpecification.LEFT_JOIN);

Java Error: illegal start of expression

public static int [] locations={1,2,3};

public static test dot=new test();

Declare the above variables above the main method and the code compiles fine.

public static void main(String[] args){

How to sort a list of strings numerically?

If you want to use strings of the numbers better take another list as shown in my code it will work fine.


for item in list1:    

# [1, 2, 3, 4, 10, 22, 23, 200]

How to track down access violation "at address 00000000"

The accepted answer does not tell the entire story.

Yes, whenever you see zeros, a NULL pointer is involved. That is because NULL is by definition zero. So calling zero NULL may not be saying much.

What is interesting about the message you get is the fact that NULL is mentioned twice. In fact, the message you report looks a little bit like the messages Windows-brand operating systems show the user.

The message says the address NULL tried to read NULL. So what does that mean? Specifically, how does an address read itself?

We typically think of the instructions at an address reading and writing from memory at certain addresses. Knowing that allows us to parse the error message. The message is trying to articulate that the instruction at address NULL tried to read NULL.

Of course, there is no instruction at address NULL, that is why we think of NULL as special in our code. But every instruction can be thought of as commencing with the attempt to read itself. If the CPUs EIP register is at address NULL, then the CPU will attempt to read the opcode for an instruction from address 0x00000000 (NULL). This attempt to read NULL will fail, and generate the message you have received.

In the debugger, notice that EIP equals 0x00000000 when you receive this message. This confirms the description I have given you.

The question then becomes, "why does my program attempt to execute the NULL address." There are three possibilities which spring to mind:

  • You have attempt to make a function call via a function pointer which you have declared, assigned to NULL, never initialized otherwise, and are dereferencing.
  • Similarly, you may be calling an "abstract" C++ method which has a NULL entry in the object's vtable. These are created in your code with the syntax virtual function_name()=0.
  • In your code, a stack buffer has been overflowed while writing zeros. The zeros have been written beyond the end of the stack buffer, over the preserved return address. When the function later executes its ret instruction, the value 0x00000000 (NULL) is loaded from the overwritten memory spot. This type of error, stack overflow, is the eponym of our forum.

Since you mention that you are calling a third-party library, I will point out that it may be a situation of the library expecting you to provide a non-NULL function pointer as input to some API. These are sometimes known as "call back" functions.

You will have to use the debugger to narrow down the cause of your problem further, but the above possiblities should help you solve the riddle.

grep for special characters in Unix

grep -n "\*\^\%\Q\&\$\&\^\@\$\&\!\^\@\$\&\^\&\^\&\^\&" test.log

Video streaming over websockets using JavaScript

To answer the question:

What is the fastest way to stream live video using JavaScript? Is WebSockets over TCP a fast enough protocol to stream a video of, say, 30fps?

Yes, Websocket can be used to transmit over 30 fps and even 60 fps.

The main issue with Websocket is that it is low-level and you have to deal with may other issues than just transmitting video chunks. All in all it's a great transport for video and also audio.

How to upload images into MySQL database using PHP code

This is the perfect code for uploading and displaying image through MySQL database.

<form method="post" enctype="multipart/form-data">
<input type="file" name="image"/>
<input type="submit" name="submit" value="Upload"/>
        echo " error ";
        $image = $_FILES['image']['tmp_name'];
        $image = addslashes(file_get_contents($image));
    function saveimage($image)
        $qry="insert into tablename (name) values ('$image')";
            echo " <br/>Image uploaded.";
            echo " error ";

"ImportError: No module named" when trying to run Python script

Before installing ipython, I installed modules through easy_install; say sudo easy_install mechanize.

After installing ipython, I had to re-run easy_install for ipython to recognize the modules.

How to stash my previous commit?

It's works for me;

  1. Checkout on commit that is a origin of current branch.
  2. Create new branch from this commit.
  3. Checkout to new branch.
  4. Merge branch with code for stash in new branch.
  5. Make soft reset in new branch.
  6. Stash your target code.
  7. Remove new branch.

I recommend use something like a SourceTree for this.

jquery (or pure js) simulate enter key pressed for testing

Demo Here

var e = jQuery.Event("keypress");
e.which = 13; //choose the one you want
e.keyCode = 13;

jquery - How to determine if a div changes its height or any css attribute?

Another simple example.

For this sample we can use 100x100 DIV-box:

<div id="box" style="width: 100px; height: 100px; border: solid 1px red;">
 // Red box contents here...

And small jQuery trick:

<script type="text/javascript">
  jQuery("#box").bind("resize", function() {
    alert("Box was resized from 100x100 to 200x200");


  1. We created DIV block element for resizing operatios
  2. Add simple JavaScript code with:
    • jQuery bind
    • jQuery resizer with trigger action "resize" - trigger is most important thing in my example
  3. After resize you can check the browser alert information

That's all. ;-)

PySpark 2.0 The size or shape of a DataFrame

I think there is not similar function like data.shape in Spark. But I will use len(data.columns) rather than len(data.dtypes)

Use of def, val, and var in scala

To provide another perspective, "def" in Scala means something that will be evaluated each time when it's used, while val is something that is evaluated immediately and only once. Here, the expression def person = new Person("Kumar",12) entails that whenever we use "person" we will get a new Person("Kumar",12) call. Therefore it's natural that the two "person.age" are non-related.

This is the way I understand Scala(probably in a more "functional" manner). I'm not sure if

def defines a method
val defines a fixed value (which cannot be modified)
var defines a variable (which can be modified)

is really what Scala intends to mean though. I don't really like to think that way at least...

CakePHP select default value in SELECT input

In CakePHP 1.3, use 'default'=>value to select the default value in a select input:

$this->Form->input('', array('type'=>'select', 'label'=>'Leaf', 'options'=>$leafs, 'default'=>'3'));

Eclipse cannot load SWT libraries

For Windows Subsystem for Linux (WSL) you'll need

apt install libswt-gtk-4-jni

If you don't have an OpenJDK 8 you'll also need

apt install openjdk-8-jdk

Error:Execution failed for task ':app:dexDebug'.

This could also be the case when you have too many object references. Take a look at the results from the build, esp in the task :dex:multiDebug:

trouble writing output: Too many method references: 67114; max is 65536.

How to modify memory contents using GDB?

Expanding on the answers provided here.

You can just do set idx = 1 to set a variable, but that syntax is not recommended because the variable name may clash with a set sub-command. As an example set w=1 would not be valid.

This means that you should prefer the syntax: set variable idx = 1 or set var idx = 1.

Last but not least, you can just use your trusty old print command, since it evaluates an expression. The only difference being that he also prints the result of the expression.

(gdb) p idx = 1
$1 = 1

You can read more about gdb here.

Print a list of all installed node.js modules

If you are only interested in the packages installed globally without the full TREE then:

npm -g ls --depth=0

or locally (omit -g) :

npm ls --depth=0

Count the items from a IEnumerable<T> without iterating?

I used such way inside a method to check the passed in IEnumberable content

if( iEnum.Cast<Object>().Count() > 0) 


Inside a method like this:

GetDataTable(IEnumberable iEnum)
    if (iEnum != null && iEnum.Cast<Object>().Count() > 0) //--- proceed further


Global Variable in app.js accessible in routes?

A neat way to do this is to use app.locals provided by Express itself. Here is the documentation.

// In app.js:
app.locals.variable_you_need = 42;

// In index.js
exports.route = function(req, res){
    var variable_i_needed =;

What is the fastest way to compare two sets in Java?

I think method reference with equals method can be used. We assume that the object type without a shadow of a doubt has its own comparison method. Plain and simple example is here,

Set<String> set = new HashSet<>();

Set<String> set2 = new HashSet<>();

Predicate<Set> pred = set::equals;
boolean result = pred.test(set2);
System.out.println(result);   // true

Add Text on Image using PIL

Even more minimal example (draws "Hello world!" in black and with the default font in the top-left of the image):

from PIL import ImageDraw
    image  # Image
    (0, 0),  # Coordinates
    'Hello world!',  # Text
    (0, 0, 0)  # Color

How to check for a Null value in VB.NET

This is the exact answer. Try this code:

If String.IsNullOrEmpty(editTransactionRow.pay_id.ToString()) = False Then
    stTransactionPaymentID = editTransactionRow.pay_id 'Check for null value
End If

Notepad++ Setting for Disabling Auto-open Previous Files

Ok, I had a problem with Notepad++ not remembering that I had chosen not the "Remember Current Session". I tried hacking the config file, but that didn't work. Then I found out that there is a secret config file in your C:\Users\myuseraccount\AppData\Roaming\Notepad++ directory (Windows 7 x64). Mine was empty, meaning who know where the config was really coming from, but I copied over the file with the one in C:\Program Files (x86)\Notepad++ and now everything works just like you would expect it to.

shorthand c++ if else statement


bigInt.sign = !(number < 0);

The ! operator always evaluates to true or false. When converted to int, these become 1 and 0 respectively.

Of course this is equivalent to:

bigInt.sign = (number >= 0);

Here the parentheses are redundant but I add them for clarity. All of the comparison and relational operator evaluate to true or false.

How to convert an Image to base64 string in java?

The problem is that you are returning the toString() of the call to Base64.encodeBase64(bytes) which returns a byte array. So what you get in the end is the default string representation of a byte array, which corresponds to the output you get.

Instead, you should do:

encodedfile = new String(Base64.encodeBase64(bytes), "UTF-8");

Multiple Buttons' OnClickListener() android

Implement onClick() method in your Activity/Fragment public class MainActivity extends Activity implements View.OnClickListener {

    protected void onCreate(Bundle savedInstanceState) {

    public void onClick(View v) {
 switch (itemId) {

// if you call the fragment with nevigation bar then used.

                fragment = new IntroductionFragment();

// if call activity with nevigation bar then used.

                Intent i = new Intent(MainActivity.this, YoutubeActivity.class);
      // default method for handling onClick Events..

How to make circular background using css?


div {
  width: 400px; height: 400px;
  background: radial-gradient(ellipse at center,  #f73134 0%,#ff0000 47%,#ff0000 47%,#23bc2b 47%,#23bc2b 48%);

How to create a shared library with cmake?

First, this is the directory layout that I am using:

+-- include
¦   +-- class1.hpp
¦   +-- ...
¦   +-- class2.hpp
+-- src
    +-- class1.cpp
    +-- ...
    +-- class2.cpp

After a couple of days taking a look into this, this is my favourite way of doing this thanks to modern CMake:

cmake_minimum_required(VERSION 3.5)
project(mylib VERSION 1.0.0 LANGUAGES CXX)


  message(STATUS "Setting build type to '${DEFAULT_BUILD_TYPE}' as none was specified.")
  set(CMAKE_BUILD_TYPE "${DEFAULT_BUILD_TYPE}" CACHE STRING "Choose the type of build." FORCE)
  # Set the possible values of build type for cmake-gui
  set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS "Debug" "Release" "MinSizeRel" "RelWithDebInfo")


set(SOURCE_FILES src/class1.cpp src/class2.cpp)

add_library(${PROJECT_NAME} ...)

target_include_directories(${PROJECT_NAME} PUBLIC
    PRIVATE src)

set_target_properties(${PROJECT_NAME} PROPERTIES


install(EXPORT MyLibConfig DESTINATION share/MyLib/cmake)

export(TARGETS ${PROJECT_NAME} FILE MyLibConfig.cmake)

After running CMake and installing the library, there is no need to use Find***.cmake files, it can be used like this:

find_package(MyLib REQUIRED)

#No need to perform include_directories(...)
target_link_libraries(${TARGET} mylib)

That's it, if it has been installed in a standard directory it will be found and there is no need to do anything else. If it has been installed in a non-standard path, it is also easy, just tell CMake where to find MyLibConfig.cmake using:

cmake -DMyLib_DIR=/non/standard/install/path ..

I hope this helps everybody as much as it has helped me. Old ways of doing this were quite cumbersome.

Should I use 'border: none' or 'border: 0'?

Both are valid. It's your choice.

I prefer border:0 because it's shorter; I find that easier to read. You may find none more legible. We live in a world of very capable CSS post-processors so I'd recommend you use whatever you prefer and then run it through a "compressor". There's no holy war worth fighting here but Webpack?LESS?PostCSS?PurgeCSS is a good 2020 stack.

That all said, if you're hand-writing all your production CSS, I maintain —despite the grumbling in the comments— it does not hurt to be bandwidth conscious. Using border:0 will save an infinitesimal amount of bandwidth on its own, but if you make every byte count, you will make your website faster.

The CSS2 specs are here. These are extended in CSS3 but not in any way relevant to this.

    Value:      [ <border-width> || <border-style> || <'border-top-color'> ] | inherit
    Initial:    see individual properties
    Applies to:     all elements
    Inherited:      no
    Percentages:    N/A
    Media:      visual
    Computed value:     see individual properties 

You can use any combination of width, style and colour.
Here, 0 sets the width, none the style. They have the same rendering result: nothing is shown.

Prefer composition over inheritance?

To address this question from a different perspective for newer programmers:

Inheritance is often taught early when we learn object-oriented programming, so it's seen as an easy solution to a common problem.

I have three classes that all need some common functionality. So if I write a base class and have them all inherit from it, then they will all have that functionality and I'll only need to maintain it in once place.

It sounds great, but in practice it almost never, ever works, for one of several reasons:

  • We discover that there are some other functions that we want our classes to have. If the way that we add functionality to classes is through inheritance, we have to decide - do we add it to the existing base class, even though not every class that inherits from it needs that functionality? Do we create another base class? But what about classes that already inherit from the other base class?
  • We discover that for just one of the classes that inherits from our base class we want the base class to behave a little differently. So now we go back and tinker with our base class, maybe adding some virtual methods, or even worse, some code that says, "If I'm inherited type A, do this, but if I'm inherited type B, do that." That's bad for lots of reasons. One is that every time we change the base class, we're effectively changing every inherited class. So we're really changing class A, B, C, and D because we need a slightly different behavior in class A. As careful as we think we are, we might break one of those classes for reasons that have nothing to do with those classes.
  • We might know why we decided to make all of these classes inherit from each other, but it might not (probably won't) make sense to someone else who has to maintain our code. We might force them into a difficult choice - do I do something really ugly and messy to make the change I need (see the previous bullet point) or do I just rewrite a bunch of this.

In the end, we tie our code in some difficult knots and get no benefit whatsoever from it except that we get to say, "Cool, I learned about inheritance and now I used it." That's not meant to be condescending because we've all done it. But we all did it because no one told us not to.

As soon as someone explained "favor composition over inheritance" to me, I thought back over every time I tried to share functionality between classes using inheritance and realized that most of the time it didn't really work well.

The antidote is the Single Responsibility Principle. Think of it as a constraint. My class must do one thing. I must be able to give my class a name that somehow describes that one thing it does. (There are exceptions to everything, but absolute rules are sometimes better when we're learning.) It follows that I cannot write a base class called ObjectBaseThatContainsVariousFunctionsNeededByDifferentClasses. Whatever distinct functionality I need must be in its own class, and then other classes that need that functionality can depend on that class, not inherit from it.

At the risk of oversimplifying, that's composition - composing multiple classes to work together. And once we form that habit we find that it's much more flexible, maintainable, and testable than using inheritance.

How to move or copy files listed by 'find' command in unix?

Actually, you can process the find command output in a copy command in two ways:

  1. If the find command's output doesn't contain any space, i.e if the filename doesn't contain a space in it, then you can use:

        find <Path> <Conditions> | xargs cp -t <copy file path>
        find -mtime -1 -type f | xargs cp -t inner/
  2. But our production data files might contain spaces, so most of time this command is effective:

       find <path> <condition> -exec cp '{}' <copy path> \;
       find -mtime -1 -type f -exec cp '{}' inner/ \;

In the second example, the last part, the semi-colon is also considered as part of the find command, and should be escaped before pressing Enter. Otherwise you will get an error something like:

find: missing argument to `-exec'

Output in a table format in Java's System.out

public class Main {
 public static void main(String args[]) {
   String format = "|%1$-10s|%2$-10s|%3$-20s|\n";
   System.out.format(format, "A", "AA", "AAA");
   System.out.format(format, "B", "", "BBBBB");
   System.out.format(format, "C", "CCCCC", "CCCCCCCC");

   String ex[] = { "E", "EEEEEEEEEE", "E" };

   System.out.format(String.format(format, (Object[]) ex));

differece in sizes of input doesnt effect the output

How do I tell Spring Boot which main class to use for the executable jar?

Since Spring Boot 1.5, you can complete ignore the error-prone string literal in pom or build.gradle. The repackaging tool (via maven or gradle plugin) will pick the one annotated with @SpringBootApplication for you. (Refer to this issue for detail: )

registerForRemoteNotificationTypes: is not supported in iOS 8.0 and later

iOS 8 has changed notification registration in a non-backwards compatible way. While you need to support iOS 7 and 8 (and while apps built with the 8 SDK aren't accepted), you can check for the selectors you need and conditionally call them correctly for the running version.

Here's a category on UIApplication that will hide this logic behind a clean interface for you that will work in both Xcode 5 and Xcode 6.


//Call these from your application code for both iOS 7 and 8
//put this in the public header
@interface UIApplication (RemoteNotifications)

- (BOOL)pushNotificationsEnabled;
- (void)registerForPushNotifications;



//these declarations are to quiet the compiler when using 7.x SDK
//put this interface in the implementation file of this category, so they are
//not visible to any other code.
@interface NSObject (IOS8)

- (BOOL)isRegisteredForRemoteNotifications;
- (void)registerForRemoteNotifications;

+ (id)settingsForTypes:(NSUInteger)types categories:(NSSet*)categories;
- (void)registerUserNotificationSettings:(id)settings;


@implementation UIApplication (RemoteNotifications)

- (BOOL)pushNotificationsEnabled
    if ([self respondsToSelector:@selector(isRegisteredForRemoteNotifications)])
        return [self isRegisteredForRemoteNotifications];
        return ([self enabledRemoteNotificationTypes] & UIRemoteNotificationTypeAlert);

- (void)registerForPushNotifications
    if ([self respondsToSelector:@selector(registerForRemoteNotifications)])
        [self registerForRemoteNotifications];

        Class uiUserNotificationSettings = NSClassFromString(@"UIUserNotificationSettings");

        //If you want to add other capabilities than just banner alerts, you'll need to grab their declarations from the iOS 8 SDK and define them in the same way.
        NSUInteger UIUserNotificationTypeAlert   = 1 << 2;

        id settings = [uiUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert categories:[NSSet set]];            
        [self registerUserNotificationSettings:settings];

        [self registerForRemoteNotificationTypes:UIRemoteNotificationTypeAlert];


Find character position and update file name

If you're working with actual files (as opposed to some sort of string data), how about the following?

$files | % { "$($_.BaseName -replace '_[^_]+$','')$($_.Extension)" }

(or use _.+$ if you want to cut everything from the first underscore.)

How to create separate AngularJS controller files?

Using the angular.module API with an array at the end will tell angular to create a new module:


// It is like saying "create a new module"
angular.module('myApp.controllers', []); // Notice the empty array at the end here

Using it without the array is actually a getter function. So to seperate your controllers, you can do:


// It is just like saying "get this module and create a controller"
angular.module('myApp.controllers').controller('Ctrlr1', ['$scope', '$http', function($scope, $http) {}]);


angular.module('myApp.controllers').controller('Ctrlr2', ['$scope', '$http', function($scope, $http) {}]);

During your javascript imports, just make sure myApp.js is after AngularJS but before any controllers / services / etc...otherwise angular won't be able to initialize your controllers.

Select rows from a data frame based on values in a vector

Another option would be to use a keyed data.table:

setDT(dt, key = 'fct')[J(vc)]  # or: setDT(dt, key = 'fct')[.(vc)]

which results in:

   fct X
1:   a 2
2:   a 7
3:   a 1
4:   c 3
5:   c 5
6:   c 9
7:   c 2
8:   c 4

What this does:

  • setDT(dt, key = 'fct') transforms the data.frame to a data.table (which is an enhanced form of a data.frame) with the fct column set as key.
  • Next you can just subset with the vc vector with [J(vc)].

NOTE: when the key is a factor/character variable, you can also use setDT(dt, key = 'fct')[vc] but that won't work when vc is a numeric vector. When vc is a numeric vector and is not wrapped in J() or .(), vc will work as a rowindex.

A more detailed explanation of the concept of keys and subsetting can be found in the vignette Keys and fast binary search based subset.

An alternative as suggested by @Frank in the comments:

setDT(dt)[J(vc), on=.(fct)]

When vc contains values that are not present in dt, you'll need to add nomatch = 0:

setDT(dt, key = 'fct')[J(vc), nomatch = 0]


setDT(dt)[J(vc), on=.(fct), nomatch = 0]

What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?

To add to what others posted:

ExecuteScalar conceptually returns the leftmost column from the first row of the resultset from the query; you could ExecuteScalar a SELECT * FROM staff, but you'd only get the first cell of the resulting rows Typically used for queries that return a single value. I'm not 100% sure about SQLServer but in Oracle, you wouldnt use it to run a FUNCTION (a database code that returns a single value) and expect it to give you the return value of the function even though functions return single values.. However, if youre running the function as part of a query, e.g. SELECT SUBSTR('abc', 1, 1) FROM DUAL then it would give the return value by virtue of the fact that the return value is stored in the top leftmost cell of the resulting rowset

ExecuteNonQuery would be used to run database stored procedures, functions and queries that modify data (INSERT/UPDATE/DELETE) or modify database structure (CREATE TABLE...). Typically the return value of the call is an indication of how many rows were affected by the operation but check the DB documentation to guarantee this

nginx showing blank PHP pages


include fastcgi_params;


include fastcgi.conf;

and remove fastcgi_param SCRIPT_FILENAME ... in nginx.conf

Automatically scroll down chat div

As I am not master in js but I myself write code which check if user is at bottom. If user is at bottom then chat page will automatically scroll with new message. and if user scroll up then page will not auto scroll to bottom..

JS code -

var checkbottom;
jQuery(function($) {
$('.chat_screen').on('scroll', function() {
    var check = $(this).scrollTop() + $(this).innerHeight() >= $(this) 
    if(check) {
       checkbottom = "bottom";
    else {
    checkbottom = "nobottom";
if (checkbottom=="bottom") {
var objDiv = document.getElementById("chat_con");
objDiv.scrollTop = objDiv.scrollHeight;
}, 500);

html code -

<div id="chat_con" class="chat_screen">

JS: Failed to execute 'getComputedStyle' on 'Window': parameter is not of type 'Element'

The error message is pretty straightforward: getComputedStyle expects an Element as its first argument, and something else was passed to it.

If what you are really asking for is help with debugging your skin, you should make more of an effort to isolate the error.

Set LIMIT with doctrine 2?

I use Doctrine\ORM\Tools\Pagination\Paginator for this, and it works perfectly (doctrine 2.2).

$dql = "SELECT p, c FROM BlogPost p JOIN p.comments c";
$query = $entityManager->createQuery($dql)

$paginator = new Paginator($query, $fetchJoinCollection = true);

how to fix java.lang.IndexOutOfBoundsException

Use if(index.length() < 0) for Integer


Use if(index.equals(null) for String