SyntaxFix

Programs & Examples On #Php parser

How to POST a FORM from HTML to ASPX page

This is very possible. I mocked up 3 pages which should give you a proof of concept:

.aspx page:

<form id="form1" runat="server">
    <div>
        <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
        <asp:TextBox TextMode="password" ID="TextBox2" runat="server"></asp:TextBox>
        <asp:Button ID="Button1" runat="server" Text="Button" />
    </div>
</form>

code behind:

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    For Each s As String In Request.Form.AllKeys
        Response.Write(s & ": " & Request.Form(s) & "<br />")
    Next
End Sub

Separate HTML page:

<form action="http://localhost/MyTestApp/Default.aspx" method="post">
    <input name="TextBox1" type="text" value="" id="TextBox1" />
    <input name="TextBox2" type="password" id="TextBox2" />
    <input type="submit" name="Button1" value="Button" id="Button1" />
</form>

...and it regurgitates the form values as expected. If this isn't working, as others suggested, use a traffic analysis tool (fiddler, ethereal), because something probably isn't going where you're expecting.

add scroll bar to table body

you can wrap the content of the <tbody> in a scrollable <div> :

html

....
<tbody>
  <tr>
    <td colspan="2">
      <div class="scrollit">
        <table>
          <tr>
            <td>January</td>
            <td>$100</td>
          </tr>
          <tr>
            <td>February</td>
            <td>$80</td>
          </tr>
          <tr>
            <td>January</td>
            <td>$100</td>
          </tr>
          <tr>
            <td>February</td>
            <td>$80</td>
          </tr>
          ...

css

.scrollit {
    overflow:scroll;
    height:100px;
}

see my jsfiddle, forked from yours: http://jsfiddle.net/VTNax/2/

Create empty data frame with column names by assigning a string vector?

How about:

df <- data.frame(matrix(ncol = 3, nrow = 0))
x <- c("name", "age", "gender")
colnames(df) <- x

To do all these operations in one-liner:

setNames(data.frame(matrix(ncol = 3, nrow = 0)), c("name", "age", "gender"))

#[1] name   age    gender
#<0 rows> (or 0-length row.names)

Or

data.frame(matrix(ncol=3,nrow=0, dimnames=list(NULL, c("name", "age", "gender"))))

Check if a input box is empty

Another approach is using regex , as show below , you can use the empty regex pattern and achieve the same using ng-pattern

HTML :

 <body ng-app="app" ng-controller="formController">
 <form name="myform">
 <input name="myfield" ng-model="somefield" ng-minlength="5" ng-pattern="mypattern" required>
 <span ng-show="myform.myfield.$error.pattern">Please enter!</span>
 <span ng-show="!myform.myfield.$error.pattern">great!</span>
</form>

Controller:@formController : 

var App = angular.module('app', []);
App.controller('formController', function ($scope) {              
  $scope.mypattern = /^\s*$/g;
});

How to test if a string is JSON or not?

Use JSON.parse

function isJson(str) {
    try {
        JSON.parse(str);
    } catch (e) {
        return false;
    }
    return true;
}

Deleting folders in python recursively

Try shutil.rmtree:

import shutil
shutil.rmtree('/path/to/your/dir/')

extract part of a string using bash/cut/split

Using a single Awk:

... | awk -F '[/:]' '{print $5}'

That is, using as field separator either / or :, the username is always in field 5.

To store it in a variable:

username=$(... | awk -F '[/:]' '{print $5}')

A more flexible implementation with sed that doesn't require username to be field 5:

... | sed -e s/:.*// -e s?.*/??

That is, delete everything from : and beyond, and then delete everything up until the last /. sed is probably faster too than awk, so this alternative is definitely better.

What is "Signal 15 received"

This indicates the linux has delivered a SIGTERM to your process. This is usually at the request of some other process (via kill()) but could also be sent by your process to itself (using raise()). This signal requests an orderly shutdown of your process.

If you need a quick cheatsheet of signal numbers, open a bash shell and:

$ kill -l
 1) SIGHUP   2) SIGINT   3) SIGQUIT  4) SIGILL
 5) SIGTRAP  6) SIGABRT  7) SIGBUS   8) SIGFPE
 9) SIGKILL 10) SIGUSR1 11) SIGSEGV 12) SIGUSR2
13) SIGPIPE 14) SIGALRM 15) SIGTERM 16) SIGSTKFLT
17) SIGCHLD 18) SIGCONT 19) SIGSTOP 20) SIGTSTP
21) SIGTTIN 22) SIGTTOU 23) SIGURG  24) SIGXCPU
25) SIGXFSZ 26) SIGVTALRM   27) SIGPROF 28) SIGWINCH
29) SIGIO   30) SIGPWR  31) SIGSYS  34) SIGRTMIN
35) SIGRTMIN+1  36) SIGRTMIN+2  37) SIGRTMIN+3  38) SIGRTMIN+4
39) SIGRTMIN+5  40) SIGRTMIN+6  41) SIGRTMIN+7  42) SIGRTMIN+8
43) SIGRTMIN+9  44) SIGRTMIN+10 45) SIGRTMIN+11 46) SIGRTMIN+12
47) SIGRTMIN+13 48) SIGRTMIN+14 49) SIGRTMIN+15 50) SIGRTMAX-14
51) SIGRTMAX-13 52) SIGRTMAX-12 53) SIGRTMAX-11 54) SIGRTMAX-10
55) SIGRTMAX-9  56) SIGRTMAX-8  57) SIGRTMAX-7  58) SIGRTMAX-6
59) SIGRTMAX-5  60) SIGRTMAX-4  61) SIGRTMAX-3  62) SIGRTMAX-2
63) SIGRTMAX-1  64) SIGRTMAX

You can determine the sender by using an appropriate signal handler like:

#include <signal.h>
#include <stdio.h>
#include <stdlib.h>

void sigterm_handler(int signal, siginfo_t *info, void *_unused)
{
  fprintf(stderr, "Received SIGTERM from process with pid = %u\n",
      info->si_pid);
  exit(0);
}

int main (void)
{
  struct sigaction action = {
    .sa_handler = NULL,
    .sa_sigaction = sigterm_handler,
    .sa_mask = 0,
    .sa_flags = SA_SIGINFO,
    .sa_restorer = NULL
  };

  sigaction(SIGTERM, &action, NULL);
  sleep(60);

  return 0;
}

Notice that the signal handler also includes a call to exit(). It's also possible for your program to continue to execute by ignoring the signal, but this isn't recommended in general (if it's a user doing it there's a good chance it will be followed by a SIGKILL if your process doesn't exit, and you lost your opportunity to do any cleanup then).

jquery: change the URL address without redirecting?

See here - http://my.opera.com/community/forums/topic.dml?id=1319992&t=1331393279&page=1#comment11751402

Essentially:

history.pushState('data', '', 'http://your-domain/path');

You can manipulate the history object to make this work.

It only works on the same domain, but since you're satisfied with using the hash tag approach, that shouldn't matter.

Obviously would need to be cross-browser tested, but since that was posted on the Opera forum I'm safe to assume it would work in Opera, and I just tested it in Chrome and it worked fine.

Javascript, viewing [object HTMLInputElement]

 
<input type="text" />
<script>
$("input:text").change(function() {
    var value=$("input:text").val();
    alert(value);
});
</script>

use .val() to get value of the element (jquery method), $("input:text") this selector to select your input, .change() to bind an event handler to the "change" JavaScript event.

Random number c++ in some range

Use the rand function:

http://www.cplusplus.com/reference/clibrary/cstdlib/rand/

Quote:

A typical way to generate pseudo-random numbers in a determined range using rand is to use the modulo of the returned value by the range span and add the initial value of the range:

( value % 100 ) is in the range 0 to 99
( value % 100 + 1 ) is in the range 1 to 100
( value % 30 + 1985 ) is in the range 1985 to 2014

Counting array elements in Python

Before I saw this, I thought to myself, "I need to make a way to do this!"

for tempVar in arrayName: tempVar+=1

And then I thought, "There must be a simpler way to do this." and I was right.

len(arrayName)

"Cannot instantiate the type..."

I had the very same issue, not being able to instantiate the type of a class which I was absolutely sure was not abstract. Turns out I was implementing an abstract class from Java.util instead of implementing my own class.

So if the previous answers did not help you, please check that you import the class you actually wanted to import, and not something else with the same name that you IDE might have hinted you.

For example, if you were trying to instantiate the class Queue from the package myCollections which you coded yourself :

import java.util.*; // replace this line
import myCollections.Queue; // by this line

     Queue<Edge> theQueue = new Queue<Edge>();

How can I check if a value is of type Integer?

If you have a double/float/floating point number and want to see if it's an integer.

public boolean isDoubleInt(double d)
{
    //select a "tolerance range" for being an integer
    double TOLERANCE = 1E-5;
    //do not use (int)d, due to weird floating point conversions!
    return Math.abs(Math.floor(d) - d) < TOLERANCE;
}

If you have a string and want to see if it's an integer. Preferably, don't throw out the Integer.valueOf() result:

public boolean isStringInt(String s)
{
    try
    {
        Integer.parseInt(s);
        return true;
    } catch (NumberFormatException ex)
    {
        return false;
    }
}

If you want to see if something is an Integer object (and hence wraps an int):

public boolean isObjectInteger(Object o)
{
    return o instanceof Integer;
}

How do I execute .js files locally in my browser?

If you're using Google Chrome you can use the Chrome Dev Editor: https://github.com/dart-lang/chromedeveditor

How to compare DateTime in C#?

 
//Time compare.
private int CompareTime(string t1, string t2)
{
    TimeSpan s1 = TimeSpan.Parse(t1);
    TimeSpan s2 = TimeSpan.Parse(t2);
    return s2.CompareTo(s1);
}

"An attempt was made to access a socket in a way forbidden by its access permissions" while using SMTP

Ok, so very important to realize the implications here.

Docs say that SSL over 465 is NOT supported in SmtpClient.

Seems like you have no choice but to use STARTTLS which may not be supported by your mail host. You may have to use a different library if your host requires use of SSL over 465.

Quoted from http://msdn.microsoft.com/en-us/library/system.net.mail.smtpclient.enablessl(v=vs.110).aspx

The SmtpClient class only supports the SMTP Service Extension for Secure SMTP over Transport Layer Security as defined in RFC 3207. In this mode, the SMTP session begins on an unencrypted channel, then a STARTTLS command is issued by the client to the server to switch to secure communication using SSL. See RFC 3207 published by the Internet Engineering Task Force (IETF) for more information.

An alternate connection method is where an SSL session is established up front before any protocol commands are sent. This connection method is sometimes called SMTP/SSL, SMTP over SSL, or SMTPS and by default uses port 465. This alternate connection method using SSL is not currently supported.

Animate the transition between fragments

Here's a slide in/out animation between fragments:

FragmentTransaction transaction = getFragmentManager().beginTransaction();
transaction.setCustomAnimations(R.animator.enter_anim, R.animator.exit_anim);
transaction.replace(R.id.listFragment, new YourFragment());
transaction.commit();

We are using an objectAnimator.

Here are the two xml files in the animator subfolder.

enter_anim.xml

<?xml version="1.0" encoding="utf-8"?>
<set>
     <objectAnimator
         xmlns:android="http://schemas.android.com/apk/res/android"
         android:duration="1000"
         android:propertyName="x"
         android:valueFrom="2000"
         android:valueTo="0"
         android:valueType="floatType" />
</set>

exit_anim.xml

<?xml version="1.0" encoding="utf-8"?>
<set>
    <objectAnimator
        xmlns:android="http://schemas.android.com/apk/res/android"
        android:duration="1000"
        android:propertyName="x"
        android:valueFrom="0"
        android:valueTo="-2000"
        android:valueType="floatType" />
</set>

I hope that would help someone.

jQuery get the rendered height of an element?

Definitely use 

$('#someDiv').height()   // to read it

or

$('#someDiv').height(newHeight)  // to set it

I'm posting this as an additional answer because theres a couple important things I just learnt.

I almost fell into the trap just now of using offsetHeight. This is what happened :

  • I used the good old trick of using a debugger to 'watch' what properties my element has
  • I saw which one has a value around the value I was expecting
  • It was offsetHeight - so I used that.
  • Then i realized it didnt work with a hidden DIV
  • I tried hiding after calculating maxHeight but that looked clumsy - got in a mess.
  • I did a search - discovered jQuery.height() - and used it
  • found out height() works even on hidden elements
  • just for fun I checked the jQuery implementation of height/width

Here's just a portion of it :

Math.max(
Math.max(document.body["scroll" + name], document.documentElement["scroll" + name]),
Math.max(document.body["offset" + name], document.documentElement["offset" + name])
)

Yup it looks at BOTH scroll and offset. If that fails it looks even further, taking into account browser and css compatibility issues. In other words STUFF I DONT CARE ABOUT - or want to.

But I dont have to. Thanks jQuery!

Moral of the story : if jQuery has a method for something its probably for a good reason, likely related to compatibilty.

If you haven't read through the jQuery list of methods recently I suggest you take a look.

Is there any difference between DECIMAL and NUMERIC in SQL Server?

Joakim Backman's answer is specific, but this may bring additional clarity to it.

There is a minor difference. As per SQL For Dummies, 8th Edition (2013):

The DECIMAL data type is similar to NUMERIC. ... The difference is that your implementation may specify a precision greater than what you specify — if so, the implementation uses the greater precision. If you do not specify precision or scale, the implementation uses default values, as it does with the NUMERIC type.

It seems that the difference on some implementations of SQL is in data integrity. DECIMAL allows overflow from what is defined based on some system defaults, where as NUMERIC does not.

using jquery $.ajax to call a PHP function

You are going to have to expose and endpoint (URL) in your system which will accept the POST request from the ajax call in jQuery.

Then, when processing that url from PHP, you would call your function and return the result in the appropriate format (JSON most likely, or XML if you prefer).

Adding click event for a button created dynamically using jQuery

Use

$(document).on("click", "#btn_a", function(){
  alert ('button clicked');
});

to add the listener for the dynamically created button.

alert($("#btn_a").val());

will give you the value of the button

How to use std::sort to sort an array in C++

In C++0x/11 we get std::begin and std::end which are overloaded for arrays:

#include <algorithm>

int main(){
  int v[2000];
  std::sort(std::begin(v), std::end(v));
}

If you don't have access to C++0x, it isn't hard to write them yourself:

// for container with nested typedefs, non-const version
template<class Cont>
typename Cont::iterator begin(Cont& c){
  return c.begin();
}

template<class Cont>
typename Cont::iterator end(Cont& c){
  return c.end();
}

// const version
template<class Cont>
typename Cont::const_iterator begin(Cont const& c){
  return c.begin();
}

template<class Cont>
typename Cont::const_iterator end(Cont const& c){
  return c.end();
}

// overloads for C style arrays
template<class T, std::size_t N>
T* begin(T (&arr)[N]){
  return &arr[0];
}

template<class T, std::size_t N>
T* end(T (&arr)[N]){
  return arr + N;
}

Git error: src refspec master does not match any

You've created a new repository and added some files to the index, but you haven't created your first commit yet. After you've done:

 git add a_text_file.txt

... do:

 git commit -m "Initial commit."

... and those errors should go away.

ng-options with simple array init

You can use ng-repeat with option like this:

<form>
    <select ng-model="yourSelect" 
        ng-options="option as option for option in ['var1', 'var2', 'var3']"
        ng-init="yourSelect='var1'"></select>
    <input type="hidden" name="yourSelect" value="{{yourSelect}}" />
</form>

When you submit your form you can get value of input hidden.

DEMO

ng-selected ng-repeat

How to check if an integer is within a range of numbers in PHP?

using a switch case

    switch ($num){

        case ($num>= $value1 && $num<= $value2): 
            echo "within range 1";
        break;
        case ($num>= $value3 && $num<= $value4): 
            echo "within range 2";
        break;
        .
        .
        .
        .
        .

        default: //default
            echo "within no range";
        break;
     }

Java: Get month Integer from Date

Joda-Time

Alternatively, with the Joda-Time DateTime class.

//convert date to datetime
DateTime datetime = new DateTime(date);
int month = Integer.parseInt(datetime.toString("MM"))

…or…

int month = dateTime.getMonthOfYear();

How do I make a text input non-editable?

 
<input type="text" value="3" class="field left" readonly>

You could see in https://www.w3schools.com/tags/att_input_readonly.asp

The method to set "readonly":

$("input").attr("readonly", true)

to cancel "readonly"(work in jQuery): 

$("input").attr("readonly", false)

How do you represent a JSON array of strings?

I'll elaborate a bit more on ChrisR awesome answer and bring images from his awesome reference.

A valid JSON always starts with either curly braces { or square brackets [, nothing else.

{ will start an object:

left brace followed by a key string (a name that can't be repeated, in quotes), colon and a value (valid types shown below), followed by an optional comma to add more pairs of string and value at will and finished with a right brace

{ "key": value, "another key": value }

Hint: although javascript accepts single quotes ', JSON only takes double ones ".

[ will start an array:

left bracket followed by value, optional comma to add more value at will and finished with a right bracket

[value, value]

Hint: spaces among elements are always ignored by any JSON parser.

And value is an object, array, string, number, bool or null:

Image showing the 6 types a JSON value can be: string, number, JSON object, Array/list, boolean, and null

So yeah, ["a", "b"] is a perfectly valid JSON, like you could try on the link Manish pointed.

Here are a few extra valid JSON examples, one per block:

{}

[0]

{"__comment": "json doesn't accept comments and you should not be commenting even in this way", "avoid!": "also, never add more than one key per line, like this"}

[{   "why":null} ]

{
  "not true": [0, false],
  "true": true,
  "not null": [0, 1, false, true, {
    "obj": null
  }, "a string"]
}

How to publish a website made by Node.js to Github Pages?

I was able to set up github actions to automatically commit the results of a node build command (yarn build in my case but it should work with npm too) to the gh-pages branch whenever a new commit is pushed to master.

While not completely ideal as i'd like to avoid committing the built files, it seems like this is currently the only way to publish to github pages.

I based my workflow off of this guide for a different react library, and had to make the following changes to get it to work for me:

  • updated the "setup node" step to use the version found here since the one from the sample i was basing it off of was throwing errors because it could not find the correct action.
  • remove the line containing yarn export because that command does not exist and it doesn't seem to add anything helpful (you may also want to change the build line above it to suit your needs)
  • I also added an env directive to the yarn build step so that I can include the SHA hash of the commit that generated the build inside my app, but this is optional

Here is my full github action:

name: github pages

on:
    push:
        branches:
        - master

jobs:
    deploy:
        runs-on: ubuntu-18.04
        steps:
        - uses: actions/checkout@v2

        - name: Setup Node
            uses: actions/setup-node@v2-beta
            with:
            node-version: '12'

        - name: Get yarn cache
            id: yarn-cache
            run: echo "::set-output name=dir::$(yarn cache dir)"

        - name: Cache dependencies
            uses: actions/cache@v2
            with:
            path: ${{ steps.yarn-cache.outputs.dir }}
            key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
            restore-keys: |
                ${{ runner.os }}-yarn-
        - run: yarn install --frozen-lockfile
        - run: yarn build
            env:
            REACT_APP_GIT_SHA: ${{ github.SHA }}

        - name: Deploy
            uses: peaceiris/actions-gh-pages@v3
            with:
            github_token: ${{ secrets.GITHUB_TOKEN }}
            publish_dir: ./build

Alternative solution

The docs for next.js also provides instructions for setting up with Vercel which appears to be a hosting service for node.js apps similar to github pages. I have not tried this though and so cannot speak to how well it works.

How to copy text from a div to clipboard

Create a element to be appended to the document. Set its value to the string that we want to copy to the clipboard. Append said element to the current HTML document. Use HTMLInputElement.select() to select the contents of the element. Use Document.execCommand('copy') to copy the contents of the to the clipboard. Remove the element from the document

function copyToClipboard(containertext) {
    var el = document.createElement('textarea');
    el.value = containertext;
    el.text = containertext;
    el.setAttribute('id', 'copyText');
    el.setAttribute('readonly', '');
    el.style.position = 'absolute';
    el.style.left = '-9999px';
    document.body.appendChild(el);
    var coptTextArea = document.getElementById('copyText');
    $('#copyText').text(containertext);
    coptTextArea.select();
    document.execCommand('copy');
    document.body.removeChild(el);
    /* Alert the copied text */
    alert("Copied : "+containertext, 1000);
}

jQuery or Javascript - how to disable window scroll without overflow:hidden;

You can use jquery-disablescroll to solve the problem:

  • Disable scrolling: $window.disablescroll();
  • Enable scrolling again: $window.disablescroll("undo");

Supports handleWheel, handleScrollbar, handleKeys and scrollEventKeys.

How to do case insensitive string comparison?

 
str = 'Lol', str2 = 'lOl', regex = new RegExp('^' + str + '$', 'i');
if (regex.test(str)) {
    console.log("true");
}

What's the difference between a POST and a PUT HTTP REQUEST?

Both PUT and POST are Rest Methods .

PUT - If we make the same request twice using PUT using same parameters both times, the second request will not have any effect. This is why PUT is generally used for the Update scenario,calling Update more than once with the same parameters doesn't do anything more than the initial call hence PUT is idempotent.

POST is not idempotent , for instance Create will create two separate entries into the target hence it is not idempotent so CREATE is used widely in POST.

Making the same call using POST with same parameters each time will cause two different things to happen, hence why POST is commonly used for the Create scenario

How do I install PIL/Pillow for Python 3.6?

For python version 2.x you can simply use

  • pip install pillow

But for python version 3.X you need to specify

  • (sudo) pip3 install pillow

when you enter pip in bash hit tab and you will see what options you have

How to check if current thread is not main thread

Xamarin.Android port: (C#)

public bool IsMainThread => Build.VERSION.SdkInt >= BuildVersionCodes.M
    ? Looper.MainLooper.IsCurrentThread
    : Looper.MyLooper() == Looper.MainLooper;

Usage:

if (IsMainThread) {
    // you are on UI/Main thread
}

What are the differences between 'call-template' and 'apply-templates' in XSL?

The functionality is indeed similar (apart from the calling semantics, where call-template requires a name attribute and a corresponding names template).

However, the parser will not execute the same way.

From MSDN:

Unlike <xsl:apply-templates>, <xsl:call-template> does not change the current node or the current node-list.

What is the right way to populate a DropDownList from a database?

 
public void getClientNameDropDowndata()
{
    getConnection = Connection.SetConnection(); // to connect with data base Configure manager
    string ClientName = "Select  ClientName from Client ";
    SqlCommand ClientNameCommand = new SqlCommand(ClientName, getConnection);
    ClientNameCommand.CommandType = CommandType.Text;
    SqlDataReader ClientNameData;
    ClientNameData = ClientNameCommand.ExecuteReader();
    if (ClientNameData.HasRows)
    {
        DropDownList_ClientName.DataSource = ClientNameData;
        DropDownList_ClientName.DataValueField = "ClientName";
        DropDownList_ClientName.DataTextField="ClientName";
        DropDownList_ClientName.DataBind();
    }
    else
    {
        MessageBox.Show("No is found");
        CloseConnection = new Connection();
        CloseConnection.closeConnection(); // close the connection 
    }
}

Align contents inside a div

You can do it like this also:

HTML

<body>
    <div id="wrapper_1">
        <div id="container_1"></div>
    </div>
</body>

CSS

body { width: 100%; margin: 0; padding: 0; overflow: hidden; }

#wrapper_1 { clear: left; float: left; position: relative; left: 50%; }

#container_1 { display: block; float: left; position: relative; right: 50%; }

As Artem Russakovskii mentioned also, read the original article by Mattew James Taylor for full description.

Sort matrix according to first column in R

If your data is in a matrix named foo, the line you would run is

foo.sorted=foo[order[foo[,1]]

Moment.js - two dates difference in number of days

 
const FindDate = (date, allDate) => {
        
    // moment().diff only works on moment(). Make sure both date and elements in allDate array are in moment format
    let nearestDate = -1; 
    
    allDate.some(d => {
        const currentDate = moment(d)
        const difference = currentDate.diff(d); // Or d.diff(date) depending on what you're trying to find
        if(difference >= 0){
            nearestDate = d
        }
    });
    
    console.log(nearestDate)
}

Difference between attr_accessor and attr_accessible

attr_accessor is a Ruby method that makes a getter and a setter. attr_accessible is a Rails method that allows you to pass in values to a mass assignment: new(attrs) or update_attributes(attrs).

Here's a mass assignment:

Order.new({ :type => 'Corn', :quantity => 6 })

You can imagine that the order might also have a discount code, say :price_off. If you don't tag :price_off as attr_accessible you stop malicious code from being able to do like so:

Order.new({ :type => 'Corn', :quantity => 6, :price_off => 30 })

Even if your form doesn't have a field for :price_off, if it's in your model it's available by default. This means a crafted POST could still set it. Using attr_accessible white lists those things that can be mass assigned.

Slice indices must be integers or None or have __index__ method

Your debut and fin values are floating point values, not integers, because taille is a float.

Make those values integers instead:

item = plateau[int(debut):int(fin)]

Alternatively, make taille an integer:

taille = int(sqrt(len(plateau)))

How to find reason of failed Build without any error or warning
  • If solution contains more than one project, try building them one at a time.
  • Try restart Visual Studio.
  • Try restart Computer.
  • Try "Rebuild all"
  • Try "Clean Solution" then remove your "vspscc" files and "vssscc" files and then restart Visual Studio and then "Rebuild All".

I am getting "java.lang.ClassNotFoundException: com.google.gson.Gson" error even though it is defined in my classpath

Click on Deployment Assembly ( right above Java Build Path that you show as active ) and make sure that you see json-lib-2.4-jdk15.jar there.

Usually, you should add it to your build path and export it from your project. Once it's exported you will see the WTP warning that it's not a part of the deployment. Choose the Quick Fix option and add it to your deployment path.

The project type is not supported by this installation

If you are using VS 2010 and it is a ASP.NET project make sure you have the Visual Developer installed from the VS 2010 CD. This is not the free one, but part of what is required to work on ASP.NET projects in Visual Studio.

CFLAGS, CCFLAGS, CXXFLAGS - what exactly do these variables control?

As you noticed, these are Makefile {macros or variables}, not compiler options. They implement a set of conventions. (Macros is an old name for them, still used by some. GNU make doc calls them variables.)

The only reason that the names matter is the default make rules, visible via make -p, which use some of them.

If you write all your own rules, you get to pick all your own macro names.

In a vanilla gnu make, there's no such thing as CCFLAGS. There are CFLAGS, CPPFLAGS, and CXXFLAGS. CFLAGS for the C compiler, CXXFLAGS for C++, and CPPFLAGS for both.

Why is CPPFLAGS in both? Conventionally, it's the home of preprocessor flags (-D, -U) and both c and c++ use them. Now, the assumption that everyone wants the same define environment for c and c++ is perhaps questionable, but traditional.

P.S. As noted by James Moore, some projects use CPPFLAGS for flags to the C++ compiler, not flags to the C preprocessor. The Android NDK, for one huge example.

JavaFX - create custom button with image

A combination of previous 2 answers did the trick. Thanks. A new class which inherits from Button. Note: updateImages() should be called before showing the button.

import javafx.event.EventHandler;
import javafx.scene.control.Button;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.input.MouseEvent;

public class ImageButton extends Button {

    public void updateImages(final Image selected, final Image unselected) {
        final ImageView iv = new ImageView(selected);
        this.getChildren().add(iv);

        iv.setOnMousePressed(new EventHandler<MouseEvent>() {
            public void handle(MouseEvent evt) {
                iv.setImage(unselected);
            }
        });
        iv.setOnMouseReleased(new EventHandler<MouseEvent>() {
            public void handle(MouseEvent evt) {
                iv.setImage(selected);
            }
        });

        super.setGraphic(iv);
    }
}

angular 2 ngIf and CSS transition/animation

In my case I declared the animation on the wrong component by mistake.

app.component.html

  <app-order-details *ngIf="orderDetails" [@fadeInOut] [orderDetails]="orderDetails">
  </app-order-details>

The animation needs to be declared on the component where the element is used in (appComponent.ts). I was declaring the animation on OrderDetailsComponent.ts instead.

Hopefully it will help someone making the same mistake

Vertical Tabs with JQuery?

I wouldn't expect vertical tabs to need different Javascript from horizontal tabs. The only thing that would be different is the CSS for presenting the tabs and content on the page. JS for tabs generally does no more than show/hide/maybe load content.

How to process a file in PowerShell line-by-line as a stream

If you want to use straight PowerShell check out the below code.

$content = Get-Content C:\Users\You\Documents\test.txt
foreach ($line in $content)
{
    Write-Host $line
}

Your project path contains non-ASCII characters android studio

I have the same problem.then I create a new project and the path only use English alphabet,the problem is resolved.

Can we install Android OS on any Windows Phone and vice versa, and same with iPhone and vice versa?

Android needs to be compiled for every hardware plattform / every device model seperatly with the specific drivers etc. If you manage to do that you need also break the security arrangements every manufacturer implements to prevent the installation of other software - these are also different between each model / manufacturer. So it is possible at in theory, but only there :-)

Convert LocalDate to LocalDateTime or java.sql.Timestamp

Depending on your timezone, you may lose a few minutes (1650-01-01 00:00:00 becomes 1649-12-31 23:52:58)

Use the following code to avoid that

new Timestamp(localDateTime.getYear() - 1900, localDateTime.getMonthOfYear() - 1, localDateTime.getDayOfMonth(), localDateTime.getHourOfDay(), localDateTime.getMinuteOfHour(), localDateTime.getSecondOfMinute(), fractional);

How to open VMDK File of the Google-Chrome-OS bundle 2012?

Create a new Virtual machine in Virtual box, Select OS type Other and version Other/Unknown

On the Virtual Hard Disk screen, select "Use existing hard disk" and enter the path to the VMDK file.

It should boot your Chrome OS just fine.... BTW Chrome OS goes from VBOX bios screen to login in 7 seconds on my system!!!

Connect to SQL Server database from Node.js

This is mainly for future readers. As the question (at least the title) focuses on "connecting to sql server database from node js", I would like to chip in about "mssql" node module.

At this moment, we have a stable version of Microsoft SQL Server driver for NodeJs ("msnodesql") available here: https://www.npmjs.com/package/msnodesql. While it does a great job of native integration to Microsoft SQL Server database (than any other node module), there are couple of things to note about.

"msnodesql" require a few pre-requisites (like python, VC++, SQL native client etc.) to be installed on the host machine. That makes your "node" app "Windows" dependent. If you are fine with "Windows" based deployment, working with "msnodesql" is the best.

On the other hand, there is another module called "mssql" (available here https://www.npmjs.com/package/mssql) which can work with "tedious" or "msnodesql" based on configuration. While this module may not be as comprehensive as "msnodesql", it pretty much solves most of the needs.

If you would like to start with "mssql", I came across a simple and straight forward video, which explains about connecting to Microsoft SQL Server database using NodeJs here: https://www.youtube.com/watch?v=MLcXfRH1YzE

Source code for the above video is available here: http://techcbt.com/Post/341/Node-js-basic-programming-tutorials-videos/how-to-connect-to-microsoft-sql-server-using-node-js

Just in case, if the above links are not working, I am including the source code here:

_x000D_
_x000D_ 
var sql = require("mssql");_x000D_
_x000D_
var dbConfig = {_x000D_
    server: "localhost\\SQL2K14",_x000D_
    database: "SampleDb",_x000D_
    user: "sa",_x000D_
    password: "sql2014",_x000D_
    port: 1433_x000D_
};_x000D_
_x000D_
function getEmp() {_x000D_
    var conn = new sql.Connection(dbConfig);_x000D_
    _x000D_
    conn.connect().then(function () {_x000D_
        var req = new sql.Request(conn);_x000D_
        req.query("SELECT * FROM emp").then(function (recordset) {_x000D_
            console.log(recordset);_x000D_
            conn.close();_x000D_
        })_x000D_
        .catch(function (err) {_x000D_
            console.log(err);_x000D_
            conn.close();_x000D_
        });        _x000D_
    })_x000D_
    .catch(function (err) {_x000D_
        console.log(err);_x000D_
    });_x000D_
_x000D_
    //--> another way_x000D_
    //var req = new sql.Request(conn);_x000D_
    //conn.connect(function (err) {_x000D_
    //    if (err) {_x000D_
    //        console.log(err);_x000D_
    //        return;_x000D_
    //    }_x000D_
    //    req.query("SELECT * FROM emp", function (err, recordset) {_x000D_
    //        if (err) {_x000D_
    //            console.log(err);_x000D_
    //        }_x000D_
    //        else { _x000D_
    //            console.log(recordset);_x000D_
    //        }_x000D_
    //        conn.close();_x000D_
    //    });_x000D_
    //});_x000D_
_x000D_
}_x000D_
_x000D_
getEmp();
_x000D_
_x000D_
_x000D_

The above code is pretty self explanatory. We define the db connection parameters (in "dbConfig" JS object) and then use "Connection" object to connect to SQL Server. In order to execute a "SELECT" statement, in this case, it uses "Request" object which internally works with "Connection" object. The code explains both flavors of using "promise" and "callback" based executions.

The above source code explains only about connecting to sql server database and executing a SELECT query. You can easily take it to the next level by following documentation of "mssql" node available at: https://www.npmjs.com/package/mssql

UPDATE: There is a new video which does CRUD operations using pure Node.js REST standard (with Microsoft SQL Server) here: https://www.youtube.com/watch?v=xT2AvjQ7q9E. It is a fantastic video which explains everything from scratch (it has got heck a lot of code and it will not be that pleasing to explain/copy the entire code here)

How do I center a Bootstrap div with a 'spanX' class?

Twitter's bootstrap .span classes are floated to the left so they won't center by usual means. So, if you want it to center your span simply add float:none to your #main rule.

CSS

#main {
 margin:0 auto;
 float:none;
}

Why is it common to put CSRF prevention tokens in cookies?

A good reason, which you have sort of touched on, is that once the CSRF cookie has been received, it is then available for use throughout the application in client script for use in both regular forms and AJAX POSTs. This will make sense in a JavaScript heavy application such as one employed by AngularJS (using AngularJS doesn't require that the application will be a single page app, so it would be useful where state needs to flow between different page requests where the CSRF value cannot normally persist in the browser).

Consider the following scenarios and processes in a typical application for some pros and cons of each approach you describe. These are based on the Synchronizer Token Pattern.

Request Body Approach

  1. User successfully logs in.
  2. Server issues auth cookie.
  3. User clicks to navigate to a form.
  4. If not yet generated for this session, server generates CSRF token, stores it against the user session and outputs it to a hidden field.
  5. User submits form.
  6. Server checks hidden field matches session stored token.

Advantages:

  • Simple to implement.
  • Works with AJAX.
  • Works with forms.
  • Cookie can actually be HTTP Only.

Disadvantages:

  • All forms must output the hidden field in HTML.
  • Any AJAX POSTs must also include the value.
  • The page must know in advance that it requires the CSRF token so it can include it in the page content so all pages must contain the token value somewhere, which could make it time consuming to implement for a large site.

Custom HTTP Header (downstream)

  1. User successfully logs in.
  2. Server issues auth cookie.
  3. User clicks to navigate to a form.
  4. Page loads in browser, then an AJAX request is made to retrieve the CSRF token.
  5. Server generates CSRF token (if not already generated for session), stores it against the user session and outputs it to a header.
  6. User submits form (token is sent via hidden field).
  7. Server checks hidden field matches session stored token.

Advantages:

Disadvantages:

  • Doesn't work without an AJAX request to get the header value.
  • All forms must have the value added to its HTML dynamically.
  • Any AJAX POSTs must also include the value.
  • The page must make an AJAX request first to get the CSRF token, so it will mean an extra round trip each time.
  • Might as well have simply output the token to the page which would save the extra request.

Custom HTTP Header (upstream)

  1. User successfully logs in.
  2. Server issues auth cookie.
  3. User clicks to navigate to a form.
  4. If not yet generated for this session, server generates CSRF token, stores it against the user session and outputs it in the page content somewhere.
  5. User submits form via AJAX (token is sent via header).
  6. Server checks custom header matches session stored token.

Advantages:

Disadvantages:

  • Doesn't work with forms.
  • All AJAX POSTs must include the header.

Custom HTTP Header (upstream & downstream)

  1. User successfully logs in.
  2. Server issues auth cookie.
  3. User clicks to navigate to a form.
  4. Page loads in browser, then an AJAX request is made to retrieve the CSRF token.
  5. Server generates CSRF token (if not already generated for session), stores it against the user session and outputs it to a header.
  6. User submits form via AJAX (token is sent via header) .
  7. Server checks custom header matches session stored token.

Advantages:

Disadvantages:

  • Doesn't work with forms.
  • All AJAX POSTs must also include the value.
  • The page must make an AJAX request first to get the CRSF token, so it will mean an extra round trip each time.

Set-Cookie

  1. User successfully logs in.
  2. Server issues auth cookie.
  3. User clicks to navigate to a form.
  4. Server generates CSRF token, stores it against the user session and outputs it to a cookie.
  5. User submits form via AJAX or via HTML form.
  6. Server checks custom header (or hidden form field) matches session stored token.
  7. Cookie is available in browser for use in additional AJAX and form requests without additional requests to server to retrieve the CSRF token.

Advantages:

  • Simple to implement.
  • Works with AJAX.
  • Works with forms.
  • Doesn't necessarily require an AJAX request to get the cookie value. Any HTTP request can retrieve it and it can be appended to all forms/AJAX requests via JavaScript.
  • Once the CSRF token has been retrieved, as it is stored in a cookie the value can be reused without additional requests.

Disadvantages:

  • All forms must have the value added to its HTML dynamically.
  • Any AJAX POSTs must also include the value.
  • The cookie will be submitted for every request (i.e. all GETs for images, CSS, JS, etc, that are not involved in the CSRF process) increasing request size.
  • Cookie cannot be HTTP Only.

So the cookie approach is fairly dynamic offering an easy way to retrieve the cookie value (any HTTP request) and to use it (JS can add the value to any form automatically and it can be employed in AJAX requests either as a header or as a form value). Once the CSRF token has been received for the session, there is no need to regenerate it as an attacker employing a CSRF exploit has no method of retrieving this token. If a malicious user tries to read the user's CSRF token in any of the above methods then this will be prevented by the Same Origin Policy. If a malicious user tries to retrieve the CSRF token server side (e.g. via curl) then this token will not be associated to the same user account as the victim's auth session cookie will be missing from the request (it would be the attacker's - therefore it won't be associated server side with the victim's session).

As well as the Synchronizer Token Pattern there is also the Double Submit Cookie CSRF prevention method, which of course uses cookies to store a type of CSRF token. This is easier to implement as it does not require any server side state for the CSRF token. The CSRF token in fact could be the standard authentication cookie when using this method, and this value is submitted via cookies as usual with the request, but the value is also repeated in either a hidden field or header, of which an attacker cannot replicate as they cannot read the value in the first place. It would be recommended to choose another cookie however, other than the authentication cookie so that the authentication cookie can be secured by being marked HttpOnly. So this is another common reason why you'd find CSRF prevention using a cookie based method.

Multiple values in single-value context

How about this way?

package main

import (
    "fmt"
    "errors"
)

type Item struct {
    Value int
    Name string
}

var items []Item = []Item{{Value:0, Name:"zero"}, 
                        {Value:1, Name:"one"}, 
                        {Value:2, Name:"two"}}

func main() {
    var err error
    v := Get(3, &err).Value
    if err != nil {
        fmt.Println(err)
        return
    }
    fmt.Println(v)

}

func Get(value int, err *error) Item {
    if value > (len(items) - 1) {
        *err = errors.New("error")
        return Item{}
    } else {
        return items[value]
    }
}

How to move columns in a MySQL table?

phpMyAdmin provides a GUI for this within the structure view of a table. Check to select the column you want to move and click the change action at the bottom of the column list. You can then change all of the column properties and you'll find the 'move column' function at the far right of the screen.

Of course this is all just building the queries in the perfectly good top answer but GUI fans might appreciate the alternative.

my phpMyAdmin version is 4.1.7

The calling thread must be STA, because many UI components require this

If you make the call from the main thread, you must add the STAThread attribute to the Main method, as stated in the previous answer.

If you use a separate thread, it needs to be in a STA (single-threaded apartment), which is not the case for background worker threads. You have to create the thread yourself, like this:

Thread t = new Thread(ThreadProc);
t.SetApartmentState(ApartmentState.STA);

t.Start();

with ThreadProc being a delegate of type ThreadStart.

AngularJs ReferenceError: $http is not defined

Probably you haven't injected $http service to your controller. There are several ways of doing that.

Please read this reference about DI. Then it gets very simple:

function MyController($scope, $http) {
   // ... your code
}

UIDevice uniqueIdentifier deprecated - What to do now?

Apple has added a new framework in iOS 11 called DeviceCheck which will help you to get the unique identifier very easily. Read this form more information. https://medium.com/@santoshbotre01/unique-identifier-for-the-ios-devices-590bb778290d

Define a struct inside a class in C++

Something like:

class Tree {

 struct node {
   int data;
   node *llink;
   node *rlink;
 };
 .....
 .....
 .....
};

Storyboard - refer to ViewController in AppDelegate

Generally, the system should be handling view controller instantiation with a storyboard. What you want is to traverse the viewController hierarchy by grabbing a reference to the self.window.rootViewController as opposed to initializing view controllers, which should already be initialized correctly if you've setup your storyboard properly.

So, let's say your rootViewController is a UINavigationController and then you want to send something to its top view controller, you would do it like this in your AppDelegate's didFinishLaunchingWithOptions:

UINavigationController *nav = (UINavigationController *) self.window.rootViewController;
MyViewController *myVC = (MyViewController *)nav.topViewController;
myVC.data = self.data;

In Swift if would be very similar:

let nav = self.window.rootViewController as! UINavigationController;
let myVC = nav.topViewController as! MyViewController
myVc.data = self.data

You really shouldn't be initializing view controllers using storyboard id's from the app delegate unless you want to bypass the normal way storyboard is loaded and load the whole storyboard yourself. If you're having to initialize scenes from the AppDelegate you're most likely doing something wrong. I mean imagine you, for some reason, want to send data to a view controller way down the stack, the AppDelegate shouldn't be reaching way into the view controller stack to set data. That's not its business. It's business is the rootViewController. Let the rootViewController handle its own children! So, if I were bypassing the normal storyboard loading process by the system by removing references to it in the info.plist file, I would at most instantiate the rootViewController using instantiateViewControllerWithIdentifier:, and possibly its root if it is a container, like a UINavigationController. What you want to avoid is instantiating view controllers that have already been instantiated by the storyboard. This is a problem I see a lot. In short, I disagree with the accepted answer. It is incorrect unless the posters means to remove loading of the storyboard from the info.plist since you will have loaded 2 storyboards otherwise, which makes no sense. It's probably not a memory leak because the system initialized the root scene and assigned it to the window, but then you came along and instantiated it again and assigned it again. Your app is off to a pretty bad start!

Is it possible to add an HTML link in the body of a MAILTO link

It isn't possible as far as I can tell, since a link needs HTML, and mailto links don't create an HTML email.

This is probably for security as you could add javascript or iframes to this link and the email client might open up the end user for vulnerabilities.

LDAP root query syntax to search more than one specific OU

It's simple. Just change the port. Use 3268 instead of 389. If your domain name DOMAIN.LOCAL, in search put DC=DOMAIN,DC=LOCAL

Port 3268: This port is used for queries that are specifically targeted for the global catalog. LDAP requests sent to port 3268 can be used to search objects in the entire forest. However, only the attributes marked for replication to the global catalog can be returned.

Port 389: This port is used for requesting information from the Domain Controller. LDAP requests sent to port 389 can be used to search objects only within the global catalog’s home domain. However, the application can possible to obtain all of the attributes searched objects.

Splitting a dataframe string column into multiple different columns

The way via unlist and matrix seems a bit convoluted, and requires you to hard-code the number of elements (this is actually a pretty big no-go. Of course you could circumvent hard-coding that number and determine it at run-time)

I would go a different route, and construct a data frame directly from the list that strsplit returns. For me, this is conceptually simpler. There are essentially two ways of doing this:

  1. as.data.frame – but since the list is exactly the wrong way round (we have a list of rows rather than a list of columns) we have to transpose the result. We also clear the rownames since they are ugly by default (but that’s strictly unnecessary!):

    `rownames<-`(t(as.data.frame(strsplit(text, '\\.'))), NULL)

  2. Alternatively, use rbind to construct a data frame from the list of rows. We use do.call to call rbind with all the rows as separate arguments:

    do.call(rbind, strsplit(text, '\\.'))

Both ways yield the same result:

     [,1] [,2] [,3]  [,4]
[1,] "F"  "US" "CLE" "V13"
[2,] "F"  "US" "CA6" "U13"
[3,] "F"  "US" "CA6" "U13"
[4,] "F"  "US" "CA6" "U13"
[5,] "F"  "US" "CA6" "U13"
[6,] "F"  "US" "CA6" "U13"
…

Clearly, the second way is much simpler than the first.

How to find the size of an int[]?

Besides Carl's answer, the "standard" C++ way is not to use a C int array, but rather something like a C++ STL std::vector<int> list which you can query for list.size().

Using Bootstrap Tooltip with AngularJS

You can use selector option for dynamic single page applications:

jQuery(function($) {
    $(document).tooltip({
        selector: '[data-toggle="tooltip"]'
    });
});

if a selector is provided, tooltip objects will be delegated to the specified targets. In practice, this is used to enable dynamic HTML content to have tooltips added.

How to check that a string is parseable to a double?

Google's Guava library provides a nice helper method to do this: Doubles.tryParse(String). You use it like Double.parseDouble but it returns null rather than throwing an exception if the string does not parse to a double.

Entity Framework select distinct name

 
DBContext.TestAddresses.Select(m => m.NAME).Distinct();

if you have multiple column do like this:

DBContext.TestAddresses.Select(m => new {m.NAME, m.ID}).Distinct();

In this example no duplicate CategoryId and no CategoryName i hope this will help you

format statement in a string resource file

For me it worked like that in Kotlin:

my string.xml

 <string name="price" formatted="false">Price:U$ %.2f%n</string>

my class.kt

 var formatPrice: CharSequence? = null
 var unitPrice = 9990
 formatPrice = String.format(context.getString(R.string.price), unitPrice/100.0)
 Log.d("Double_CharSequence", "$formatPrice")

D/Double_CharSequence: Price :U$ 99,90

For an even better result, we can do so

 <string name="price_to_string">Price:U$ %1$s</string>

 var formatPrice: CharSequence? = null
 var unitPrice = 199990
 val numberFormat = (unitPrice/100.0).toString()
 formatPrice = String.format(context.getString(R.string.price_to_string), formatValue(numberFormat))

  fun formatValue(value: String) :String{
    val mDecimalFormat = DecimalFormat("###,###,##0.00")
    val s1 = value.toDouble()
    return mDecimalFormat.format(s1)
 }

 Log.d("Double_CharSequence", "$formatPrice")

D/Double_CharSequence: Price :U$ 1.999,90

Unity Scripts edited in Visual studio don't provide autocomplete

This page helped me fix the issue.

Fix for Unity disconnected from Visual Studio

enter image description here

In the Unity Editor, select the Edit > Preferences menu..

Select the External Tools tab on the left.

Select unity version from drop down list on the right

Click regenerate Files

You Done

How can I write data in YAML format in a file?

Link to the PyYAML documentation showing the difference for the default_flow_style parameter. To write it to a file in block mode (often more readable):

d = {'A':'a', 'B':{'C':'c', 'D':'d', 'E':'e'}}
with open('result.yml', 'w') as yaml_file:
    yaml.dump(d, yaml_file, default_flow_style=False)

produces:

A: a
B:
  C: c
  D: d
  E: e

What is 'Context' on Android?

Think of it as the VM that has siloed the process the app or service is running in. The siloed environment has access to a bunch of underlying system information and certain permitted resources. You need that context to get at those services.

What is the max size of localStorage values?

I really like cdmckay's answer, but it does not really look good to check the size in a real time: it is just too slow (2 seconds for me). This is the improved version, which is way faster and more exact, also with an option to choose how big the error can be (default 250,000, the smaller error is - the longer the calculation is):

function getLocalStorageMaxSize(error) {
  if (localStorage) {
    var max = 10 * 1024 * 1024,
        i = 64,
        string1024 = '',
        string = '',
        // generate a random key
        testKey = 'size-test-' + Math.random().toString(),
        minimalFound = 0,
        error = error || 25e4;

    // fill a string with 1024 symbols / bytes    
    while (i--) string1024 += 1e16;

    i = max / 1024;

    // fill a string with 'max' amount of symbols / bytes    
    while (i--) string += string1024;

    i = max;

    // binary search implementation
    while (i > 1) {
      try {
        localStorage.setItem(testKey, string.substr(0, i));
        localStorage.removeItem(testKey);

        if (minimalFound < i - error) {
          minimalFound = i;
          i = i * 1.5;
        }
        else break;
      } catch (e) {
        localStorage.removeItem(testKey);
        i = minimalFound + (i - minimalFound) / 2;
      }
    }

    return minimalFound;
  }
}

To test:

console.log(getLocalStorageMaxSize()); // takes .3s
console.log(getLocalStorageMaxSize(.1)); // takes 2s, but way more exact

This works dramatically faster for the standard error; also it can be much more exact when necessary.

How to abort makefile if variable not set?

TL;DR: Use the error function:

ifndef MY_FLAG
$(error MY_FLAG is not set)
endif

Note that the lines must not be indented. More precisely, no tabs must precede these lines.

Generic solution

In case you're going to test many variables, it's worth defining an auxiliary function for that:

# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
#   1. Variable name(s) to test.
#   2. (optional) Error message to print.
check_defined = \
    $(strip $(foreach 1,$1, \
        $(call __check_defined,$1,$(strip $(value 2)))))
__check_defined = \
    $(if $(value $1),, \
      $(error Undefined $1$(if $2, ($2))))

And here is how to use it: 

$(call check_defined, MY_FLAG)

$(call check_defined, OUT_DIR, build directory)
$(call check_defined, BIN_DIR, where to put binary artifacts)
$(call check_defined, \
            LIB_INCLUDE_DIR \
            LIB_SOURCE_DIR, \
        library path)


This would output an error like this:

Makefile:17: *** Undefined OUT_DIR (build directory).  Stop.

Notes:

The real check is done here:

$(if $(value $1),,$(error ...))

This reflects the behavior of the ifndef conditional, so that a variable defined to an empty value is also considered "undefined". But this is only true for simple variables and explicitly empty recursive variables:

# ifndef and check_defined consider these UNDEFINED:
explicitly_empty =
simple_empty := $(explicitly_empty)

# ifndef and check_defined consider it OK (defined):
recursive_empty = $(explicitly_empty)

As suggested by @VictorSergienko in the comments, a slightly different behavior may be desired:

$(if $(value $1) tests if the value is non-empty. It's sometimes OK if the variable is defined with an empty value. I'd use $(if $(filter undefined,$(origin $1)) ...

And:

Moreover, if it's a directory and it must exist when the check is run, I'd use $(if $(wildcard $1)). But would be another function.

Target-specific check

It is also possible to extend the solution so that one can require a variable only if a certain target is invoked.

$(call check_defined, ...) from inside the recipe

Just move the check into the recipe: 

foo :
    @:$(call check_defined, BAR, baz value)

The leading @ sign turns off command echoing and : is the actual command, a shell no-op stub.

Showing target name

The check_defined function can be improved to also output the target name (provided through the $@ variable):

check_defined = \
    $(strip $(foreach 1,$1, \
        $(call __check_defined,$1,$(strip $(value 2)))))
__check_defined = \
    $(if $(value $1),, \
        $(error Undefined $1$(if $2, ($2))$(if $(value @), \
                required by target `$@')))

So that, now a failed check produces a nicely formatted output:

Makefile:7: *** Undefined BAR (baz value) required by target `foo'.  Stop.

check-defined-MY_FLAG special target

Personally I would use the simple and straightforward solution above. However, for example, this answer suggests using a special target to perform the actual check. One could try to generalize that and define the target as an implicit pattern rule:

# Check that a variable specified through the stem is defined and has
# a non-empty value, die with an error otherwise.
#
#   %: The name of the variable to test.
#   
check-defined-% : __check_defined_FORCE
    @:$(call check_defined, $*, target-specific)

# Since pattern rules can't be listed as prerequisites of .PHONY,
# we use the old-school and hackish FORCE workaround.
# You could go without this, but otherwise a check can be missed
# in case a file named like `check-defined-...` exists in the root 
# directory, e.g. left by an accidental `make -t` invocation.
.PHONY : __check_defined_FORCE
__check_defined_FORCE :

Usage: 

foo :|check-defined-BAR

Notice that the check-defined-BAR is listed as the order-only (|...) prerequisite.

Pros:

  • (arguably) a more clean syntax

Cons:

I believe, these limitations can be overcome using some eval magic and secondary expansion hacks, although I'm not sure it's worth it.

Replace transparency in PNG images with white background

To actually remove the alpha channel from the file, use the alpha off option:

convert in.png -background white -alpha off out.png

TypeScript and React - children type?

This has always worked for me:

type Props = {
  children: JSX.Element;
};

How to echo out table rows from the db (php)

 
$sql = "SELECT * FROM MY_TABLE";
$result = mysqli_query($conn, $sql); // First parameter is just return of "mysqli_connect()" function
echo "<br>";
echo "<table border='1'>";
while ($row = mysqli_fetch_assoc($result)) { // Important line !!! Check summary get row on array ..
    echo "<tr>";
    foreach ($row as $field => $value) { // I you want you can right this line like this: foreach($row as $value) {
        echo "<td>" . $value . "</td>"; // I just did not use "htmlspecialchars()" function. 
    }
    echo "</tr>";
}
echo "</table>";

Can we use join for two different database tables?

You could use Synonyms part in the database.

enter image description here

Then in view wizard from Synonyms tab find your saved synonyms and add to view and set inner join simply. enter image description here

Error: Cannot access file bin/Debug/... because it is being used by another process

I tried all these suggestions as well as other suggestions found elsewhere and the only thing that worked for me was restarting my computer. Then I did a clean solution followed by rebuilding. I am using Visual Studio 2013 for reference.

How to set the part of the text view is clickable

 
 t= (TextView) findViewById(R.id.PP1);

 t.setText(Html.fromHtml("<bThis is normal text </b>" +
                "<a href=\"http://www.xyz-zyyx.com\">This is cliclable text</a> "));
 t.setMovementMethod(LinkMovementMethod.getInstance());

Java integer list

Let's use some java 8 feature:

IntStream.iterate(10, x -> x + 10).limit(5)
  .forEach(System.out::println);

If you need to store the numbers you can collect them into a collection eg:

List numbers = IntStream.iterate(10, x -> x + 10).limit(5)
  .boxed()
  .collect(Collectors.toList());

And some delay added:

IntStream.iterate(10, x -> x + 10).limit(5)
  .forEach(x -> {
    System.out.println(x);
    try {
      Thread.sleep(2000);
    } catch (InterruptedException e) {
      // Do something with the exception
    }  
  });

How can I connect to a Tor hidden service using cURL in PHP?

TL;DR: Set CURLOPT_PROXYTYPE to use CURLPROXY_SOCKS5_HOSTNAME if you have a modern PHP, the value 7 otherwise, and/or correct the CURLOPT_PROXY value.

As you correctly deduced, you cannot resolve .onion domains via the normal DNS system, because this is a reserved top-level domain specifically for use by Tor and such domains by design have no IP addresses to map to.

Using CURLPROXY_SOCKS5 will direct the cURL command to send its traffic to the proxy, but will not do the same for domain name resolution. The DNS requests, which are emitted before cURL attempts to establish the actual connection with the Onion site, will still be sent to the system's normal DNS resolver. These DNS requests will surely fail, because the system's normal DNS resolver will not know what to do with a .onion address unless it, too, is specifically forwarding such queries to Tor.

Instead of CURLPROXY_SOCKS5, you must use CURLPROXY_SOCKS5_HOSTNAME. Alternatively, you can also use CURLPROXY_SOCKS4A, but SOCKS5 is much preferred. Either of these proxy types informs cURL to perform both its DNS lookups and its actual data transfer via the proxy. This is required to successfully resolve any .onion domain.

There are also two additional errors in the code in the original question that have yet to be corrected by previous commenters. These are:

  • Missing semicolon at end of line 1.
  • The proxy address value is set to an HTTP URL, but its type is SOCKS; these are incompatible. For SOCKS proxies, the value must be an IP or domain name and port number combination without a scheme/protocol/prefix.

Here is the correct code in full, with comments to indicate the changes.

<?php
$url = 'http://jhiwjjlqpyawmpjx.onion/'; // Note the addition of a semicolon.
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_PROXY, "127.0.0.1:9050"); // Note the address here is just `IP:port`, not an HTTP URL.
curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_SOCKS5_HOSTNAME); // Note use of `CURLPROXY_SOCKS5_HOSTNAME`.
$output = curl_exec($ch);
$curl_error = curl_error($ch);
curl_close($ch);

print_r($output);
print_r($curl_error);

You can also omit setting CURLOPT_PROXYTYPE entirely by changing the CURLOPT_PROXY value to include the socks5h:// prefix:

// Note no trailing slash, as this is a SOCKS address, not an HTTP URL.
curl_setopt(CURLOPT_PROXY, 'socks5h://127.0.0.1:9050');

Check if a value is within a range of numbers

You must want to determine the lower and upper bound before writing the condition

function between(value,first,last) {

 let lower = Math.min(first,last) , upper = Math.max(first,last);
 return value >= lower &&  value <= upper ;

}

How do I get the difference between two Dates in JavaScript?

See JsFiddle DEMO

    var date1 = new Date();    
    var date2 = new Date("2025/07/30 21:59:00");
    //Customise date2 for your required future time

    showDiff();

function showDiff(date1, date2){

    var diff = (date2 - date1)/1000;
    diff = Math.abs(Math.floor(diff));

    var days = Math.floor(diff/(24*60*60));
    var leftSec = diff - days * 24*60*60;

    var hrs = Math.floor(leftSec/(60*60));
    var leftSec = leftSec - hrs * 60*60;

    var min = Math.floor(leftSec/(60));
    var leftSec = leftSec - min * 60;

    document.getElementById("showTime").innerHTML = "You have " + days + " days " + hrs + " hours " + min + " minutes and " + leftSec + " seconds before death.";

setTimeout(showDiff,1000);
}

for your HTML Code:

<div id="showTime"></div>

What is the difference between "long", "long long", "long int", and "long long int" in C++?

This looks confusing because you are taking long as a datatype itself.

long is nothing but just the shorthand for long int when you are using it alone.

long is a modifier, you can use it with double also as long double.

long == long int.

Both of them take 4 bytes.

How to implement a simple scenario the OO way

The approach I would take is: when reading the chapters from the database, instead of a collection of chapters, use a collection of books. This will have your chapters organised into books and you'll be able to use information from both classes to present the information to the user (you can even present it in a hierarchical way easily when using this approach).

How to save traceback / sys.exc_info() values in a variable?

Be careful when you take the exception object or the traceback object out of the exception handler, since this causes circular references and gc.collect() will fail to collect. This appears to be of a particular problem in the ipython/jupyter notebook environment where the traceback object doesn't get cleared at the right time and even an explicit call to gc.collect() in finally section does nothing. And that's a huge problem if you have some huge objects that don't get their memory reclaimed because of that (e.g. CUDA out of memory exceptions that w/o this solution require a complete kernel restart to recover).

In general if you want to save the traceback object, you need to clear it from references to locals(), like so:

import sys, traceback, gc
type, val, tb = None, None, None
try:
    myfunc()
except:
    type, val, tb = sys.exc_info()
    traceback.clear_frames(tb)
# some cleanup code
gc.collect()
# and then use the tb:
if tb:
    raise type(val).with_traceback(tb)

In the case of jupyter notebook, you have to do that at the very least inside the exception handler:

try:
    myfunc()
except:
    type, val, tb = sys.exc_info()
    traceback.clear_frames(tb)
    raise type(val).with_traceback(tb)
finally:
    # cleanup code in here
    gc.collect()

Tested with python 3.7.

p.s. the problem with ipython or jupyter notebook env is that it has %tb magic which saves the traceback and makes it available at any point later. And as a result any locals() in all frames participating in the traceback will not be freed until the notebook exits or another exception will overwrite the previously stored backtrace. This is very problematic. It should not store the traceback w/o cleaning its frames. Fix submitted here.

How do I put variable values into a text string in MATLAB?

I just realized why I was having so much trouble - in MATLAB you can't store strings of different lengths as an array using square brackets. Using square brackets concatenates strings of varying lengths into a single character array.

    >> a=['matlab','is','fun']

a =

matlabisfun

>> size(a)

ans =

     1    11

In a character array, each character in a string counts as one element, which explains why the size of a is 1X11.

To store strings of varying lengths as elements of an array, you need to use curly braces to save as a cell array. In cell arrays, each string is treated as a separate element, regardless of length.

>> a={'matlab','is','fun'}

a = 

    'matlab'    'is'    'fun'

>> size(a)

ans =

     1     3

Android change SDK version in Eclipse? Unable to resolve target android-x

This Problem is because of Path so you need to build the path using following Steps

Goto project ----->Right Click on Project Name ---->properties ---->click on Than Java Build Path option than ---> click Android 4.2.2---->Ok

Python convert tuple to string

This works:

''.join(('a', 'b', 'c', 'd', 'g', 'x', 'r', 'e'))

It will produce:

'abcdgxre'

You can also use a delimiter like a comma to produce:

'a,b,c,d,g,x,r,e'

By using:

','.join(('a', 'b', 'c', 'd', 'g', 'x', 'r', 'e'))

dyld: Library not loaded: @rpath/libswiftCore.dylib

For me none of the previous solutions worked. We discovered that there is an "Always Embed Swift Standard Libraries" flag in the Build Settings that needs to be set to YES. It was NO by default!

Build Settings > Always Embed Swift Standard Libraries

After setting this, clean the project before building again.

For keen readers some explanation The most important part is:

set the Embedded Content Contains Swift Code (EMBEDDED_CONTENT_CONTAINS_SWIFT) build setting to YES in your app as shown in Figure 2. This build setting, which specifies whether a target's product has embedded content with Swift code, tells Xcode to embed Swift standard libraries in your app when set to YES.

enter image description here

The flag was formerly called Embedded Content Contains Swift Code

Can someone explain __all__ in Python?

It's a list of public objects of that module, as interpreted by import *. It overrides the default of hiding everything that begins with an underscore.

Setting CSS pseudo-class rules from JavaScript

My trick is using an attribute selector. Attributes are easier to set up by javascript.

css

.class{ /*normal css... */}
.class[special]:after{ content: 'what you want'}

javascript

  function setSpecial(id){ document.getElementById(id).setAttribute('special', '1'); }

html

<element id='x' onclick="setSpecial(this.id)"> ...

ProgressDialog in AsyncTask

Don't know what parameter should I use?

A lot of Developers including have hard time at the beginning writing an AsyncTask because of the ambiguity of the parameters. The big reason is we try to memorize the parameters used in the AsyncTask. The key is Don't memorize. If you can visualize what your task really needs to do then writing the AsyncTask with the correct signature would be a piece of cake.

What is an AsyncTask?

AsyncTask are background task which run in the background thread. It takes an Input, performs Progress and gives Output.

ie AsyncTask<Input,Progress,Output>

Just figure out what your Input, Progress and Output are and you will be good to go.

For example

enter image description here

How does doInbackground() changes with AsyncTask parameters?

enter image description here

How doInBackground() and onPostExecute(),onProgressUpdate() are related?

enter image description here

How can You write this in a code?

 DownloadTask extends AsyncTask<String,Integer,String>{

    @Override
    public void onPreExecute(){
    }

    @Override
    public String doInbackGround(String... params)
    {
         // Download code
         int downloadPerc = // calculate that
         publish(downloadPerc);

         return "Download Success";
    }

    @Override
    public void onPostExecute(String result)
    {
         super.onPostExecute(result);
    }

    @Override
    public void onProgressUpdate(Integer... params)
    {
         // show in spinner, access UI elements
    }

}

How will you run this Task in Your Activity?

new DownLoadTask().execute("Paradise.mp3");

Why extend the Android Application class?

Not an answer but an observation: keep in mind that the data in the extended application object should not be tied to an instance of an activity, as it is possible that you have two instances of the same activity running at the same time (one in the foreground and one not being visible).

For example, you start your activity normally through the launcher, then "minimize" it. You then start another app (ie Tasker) which starts another instance of your activitiy, for example in order to create a shortcut, because your app supports android.intent.action.CREATE_SHORTCUT. If the shortcut is then created and this shortcut-creating invocation of the activity modified the data the application object, then the activity running in the background will start to use this modified application object once it is brought back to the foreground.

How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators differ?

 
<?php

    /**
     * Comparison of two PHP objects                         ==     ===
     * Checks for
     * 1. References                                         yes    yes
     * 2. Instances with matching attributes and its values  yes    no
     * 3. Instances with different attributes                yes    no
     **/

    // There is no need to worry about comparing visibility of property or
    // method, because it will be the same whenever an object instance is
    // created, however visibility of an object can be modified during run
    // time using ReflectionClass()
    // http://php.net/manual/en/reflectionproperty.setaccessible.php
    //
    class Foo
    {
        public $foobar = 1;

        public function createNewProperty($name, $value)
        {
            $this->{$name} = $value;
        }
    }

    class Bar
    {
    }
    // 1. Object handles or references
    // Is an object a reference to itself or a clone or totally a different object?
    //
    //   ==  true   Name of two objects are same, for example, Foo() and Foo()
    //   ==  false  Name of two objects are different, for example, Foo() and Bar()
    //   === true   ID of two objects are same, for example, 1 and 1
    //   === false  ID of two objects are different, for example, 1 and 2

    echo "1. Object handles or references (both == and    ===) <br />";

    $bar = new Foo();    // New object Foo() created
    $bar2 = new Foo();   // New object Foo() created
    $baz = clone $bar;   // Object Foo() cloned
    $qux = $bar;         // Object Foo() referenced
    $norf = new Bar();   // New object Bar() created
    echo "bar";
    var_dump($bar);
    echo "baz";
    var_dump($baz);
    echo "qux";
    var_dump($qux);
    echo "bar2";
    var_dump($bar2);
    echo "norf";
    var_dump($norf);

    // Clone: == true and === false
    echo '$bar == $bar2';
    var_dump($bar == $bar2); // true

    echo '$bar === $bar2';
    var_dump($bar === $bar2); // false

    echo '$bar == $baz';
    var_dump($bar == $baz); // true

    echo '$bar === $baz';
    var_dump($bar === $baz); // false

    // Object reference: == true and === true
    echo '$bar == $qux';
    var_dump($bar == $qux); // true

    echo '$bar === $qux';
    var_dump($bar === $qux); // true

    // Two different objects: == false and === false
    echo '$bar == $norf';
    var_dump($bar == $norf); // false

    echo '$bar === $norf';
    var_dump($bar === $norf); // false

    // 2. Instances with matching attributes and its values (only ==).
    //    What happens when objects (even in cloned object) have same
    //    attributes but varying values?

    // $foobar value is different
    echo "2. Instances with matching attributes  and its values (only ==) <br />";

    $baz->foobar = 2;
    echo '$foobar' . " value is different <br />";
    echo '$bar->foobar = ' . $bar->foobar . "<br />";
    echo '$baz->foobar = ' . $baz->foobar . "<br />";
    echo '$bar == $baz';
    var_dump($bar == $baz); // false

    // $foobar's value is the same again
    $baz->foobar = 1;
    echo '$foobar' . " value is the same again <br />";
    echo '$bar->foobar is ' . $bar->foobar . "<br />";
    echo '$baz->foobar is ' . $baz->foobar . "<br />";
    echo '$bar == $baz';
    var_dump($bar == $baz); // true

    // Changing values of properties in $qux object will change the property
    // value of $bar and evaluates true always, because $qux = &$bar.
    $qux->foobar = 2;
    echo '$foobar value of both $qux and $bar is 2, because $qux = &$bar' . "<br />";
    echo '$qux->foobar is ' . $qux->foobar . "<br />";
    echo '$bar->foobar is ' . $bar->foobar . "<br />";
    echo '$bar == $qux';
    var_dump($bar == $qux); // true

    // 3. Instances with different attributes (only ==)
    //    What happens when objects have different attributes even though
    //    one of the attributes has same value?
    echo "3. Instances with different attributes (only ==) <br />";

    // Dynamically create a property with the name in $name and value
    // in $value for baz object
    $name = 'newproperty';
    $value = null;
    $baz->createNewProperty($name, $value);
    echo '$baz->newproperty is ' . $baz->{$name};
    var_dump($baz);

    $baz->foobar = 2;
    echo '$foobar' . " value is same again <br />";
    echo '$bar->foobar is ' . $bar->foobar . "<br />";
    echo '$baz->foobar is ' . $baz->foobar . "<br />";
    echo '$bar == $baz';
    var_dump($bar == $baz); // false
    var_dump($bar);
    var_dump($baz);
?>

Characters allowed in GET parameter

The question asks which characters are allowed in GET parameters without encoding or escaping them.

According to RFC3986 (general URL syntax) and RFC7230, section 2.7.1 (HTTP/S URL syntax) the only characters you need to percent-encode are those outside of the query set, see the definition below.

However, there are additional specifications like HTML5, Web forms, and the obsolete Indexed search, W3C recommendation. Those documents add a special meaning to some characters notably, to symbols like = & + ;.

Other answers here suggest that most of the reserved characters should be encoded, including "/" "?". That's not correct. In fact, RFC3986, section 3.4 advises against percent-encoding "/" "?" characters.

it is sometimes better for usability to avoid percent- encoding those characters.

RFC3986 defines query component as:

query       = *( pchar / "/" / "?" )
pchar       = unreserved / pct-encoded / sub-delims / ":" / "@"
pct-encoded = "%" HEXDIG HEXDIG
sub-delims  = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="
unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"

A percent-encoding mechanism is used to represent a data octet in a component when that octet's corresponding character is outside the allowed set or is being used as a delimiter of, or within, the component.

The conclusion is that XYZ part should encode:

special: # % = & ;
Space
sub-delims
out of query set: [ ]
non ASCII encodable characters

Unless special symbols = & ; are key=value separators.

Encoding other characters is allowed but not necessary.

What's the u prefix in a Python string?

The u in u'Some String' means that your string is a Unicode string.

Q: I'm in a terrible, awful hurry and I landed here from Google Search. I'm trying to write this data to a file, I'm getting an error, and I need the dead simplest, probably flawed, solution this second.

A: You should really read Joel's Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!) essay on character sets.

Q: sry no time code pls

A: Fine. try str('Some String') or 'Some String'.encode('ascii', 'ignore'). But you should really read some of the answers and discussion on Converting a Unicode string and this excellent, excellent, primer on character encoding.

Uncaught ReferenceError: $ is not defined error in jQuery

Change the order you're including your scripts (jQuery first):

<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
<script type="text/javascript" src="./javascript.js"></script>
<script
    src="http://maps.googleapis.com/maps/api/js?key=YOUR_APIKEY&sensor=false">
</script>

Modifying CSS class property values on the fly with JavaScript / jQuery

Why not just use a .class selector to modify the properties of every object in that class?

ie:

$('.myclass').css('color: red;');

CREATE DATABASE permission denied in database 'master' (EF code-first)

I encountered what appeared to be this error. I was running on windows and found my administrator windows user did not have administrator privileges to database.

  1. Shut down SQL Server from ‘Services’

Disable Services

  1. Open cmd window (as administrator) and run single-user mode as local admin with this command (the version of MSSQL may differ):
"C:\Program Files\Microsoft SQL Server\MSSQL14.SQLEXPRESS\MSSQL\Binn\sqlservr.exe" -m -s SQLEXPRESS
  1. Open another cmd window (as administrator)
  2. Open sqlcmd on that terminal with: 
sqlcmd -S .\SQLEXPRESS
  1. Now add the sysadmin role to your user:
sp_addsrvrolemember 'domain\user', 'sysadmin'
GO
  1. Re-enable SQL Server from ‘Services’

Credit to: https://social.msdn.microsoft.com/Forums/sqlserver/en-US/76fc84f9-437c-4e71-ba3d-3c9ae794a7c4/

Python: Binding Socket: "Address already in use"

In case you face the problem using TCPServer or SimpleHTTPServer, override SocketServer.TCPServer.allow_reuse_address (python 2.7.x) or socketserver.TCPServer.allow_reuse_address (python 3.x) attribute

class MyServer(SocketServer.TCPServer):
    allow_reuse_address = True

server = MyServer((HOST, PORT), MyHandler)
server.serve_forever()

How to get a matplotlib Axes instance to plot to?

Use the gca ("get current axes") helper function:

ax = plt.gca()

Example:

import matplotlib.pyplot as plt
import matplotlib.finance
quotes = [(1, 5, 6, 7, 4), (2, 6, 9, 9, 6), (3, 9, 8, 10, 8), (4, 8, 8, 9, 8), (5, 8, 11, 13, 7)]
ax = plt.gca()
h = matplotlib.finance.candlestick(ax, quotes)
plt.show()

enter image description here

Clear text in EditText when entered

For Kotlin:

Create two extensions, one for EditText and one for TextView

EditText:

fun EditText.clear() { text.clear() }

TextView:

fun TextView.clear() { text = "" }

and use it like

myEditText.clear()

myTextView.clear()

How can I check if the array of objects have duplicate property values?

With Underscore.js A few ways with Underscore can be done. Here is one of them. Checking if the array is already unique.

function isNameUnique(values){
    return _.uniq(values, function(v){ return v.name }).length == values.length
}

With vanilla JavaScript By checking if there is no recurring names in the array.

function isNameUnique(values){
    var names = values.map(function(v){ return v.name });
    return !names.some(function(v){ 
        return names.filter(function(w){ return w==v }).length>1 
    });
}

How can I remove a commit on GitHub?

To preserve the branching and merging structure is important to use the --preserve-merges option when doing the rebase:

git rebase --preserve-merges -i HEAD^^

Error 1920 service failed to start. Verify that you have sufficient privileges to start system services

In my case I had to delete the services in my installshield project and start from square one. My original service components were added manually and I couldn't get them working, the only error I was getting was the same "Error 1920 service failed to start. Verify that you have sufficient privileges to start system services." that you were getting. After deleting my components, I re-added them using the component wizard.
enter image description here

Component Wizard looks like this

I actually had to create two new components. One was of type "Install Service".

Service Component type shown here

enter image description here

The other component I had to add was of "Control Service" type.

enter image description here

I had to choose the service that I had setup when I added the Install Service component.enter image description here

After that it worked, even though nothing looked differently from the components I had added manually. Installshield must do something behind the scenes when it wires up the service components with the component wizard.

All of this was with Install Shield 2016.

Getting Current time to display in Label. VB.net

There are several problems here:

  • Your assignment is the wrong way round; you're trying to assign a value to DateTime.Now instead of Start
  • DateTime.Now is a value of type DateTime, not Integer, so the assignment wouldn't work anyway
  • There's no need to have the Start variable anyway; it's doing no good
  • total.Text is a property of type String - not DateTime or Integer

(Some of these would only show up at execution time unless you have Option Strict on, which you really should.)

You should use:

total.Text = DateTime.Now.ToString()

... possibly specifying a culture and/or format specifier if you want the result in a particular format.

docker build with --build-arg with multiple arguments

If you want to use environment variable during build. Lets say setting username and password.

username= Ubuntu
password= swed24sw

Dockerfile

FROM ubuntu:16.04
ARG SMB_PASS
ARG SMB_USER
# Creates a new User
RUN useradd -ms /bin/bash $SMB_USER
# Enters the password twice.
RUN echo "$SMB_PASS\n$SMB_PASS" | smbpasswd -a $SMB_USER

Terminal Command

docker build --build-arg SMB_PASS=swed24sw --build-arg SMB_USER=Ubuntu . -t IMAGE_TAG

Difference between exit() and sys.exit() in Python

exit is a helper for the interactive shell - sys.exit is intended for use in programs.

The site module (which is imported automatically during startup, except if the -S command-line option is given) adds several constants to the built-in namespace (e.g. exit). They are useful for the interactive interpreter shell and should not be used in programs.

Technically, they do mostly the same: raising SystemExit. sys.exit does so in sysmodule.c:

static PyObject *
sys_exit(PyObject *self, PyObject *args)
{
    PyObject *exit_code = 0;
    if (!PyArg_UnpackTuple(args, "exit", 0, 1, &exit_code))
        return NULL;
    /* Raise SystemExit so callers may catch it or clean up. */
    PyErr_SetObject(PyExc_SystemExit, exit_code);
   return NULL;
}

While exit is defined in site.py and _sitebuiltins.py, respectively.

class Quitter(object):
    def __init__(self, name):
        self.name = name
    def __repr__(self):
        return 'Use %s() or %s to exit' % (self.name, eof)
    def __call__(self, code=None):
        # Shells like IDLE catch the SystemExit, but listen when their
        # stdin wrapper is closed.
        try:
            sys.stdin.close()
        except:
            pass
        raise SystemExit(code)
__builtin__.quit = Quitter('quit')
__builtin__.exit = Quitter('exit')

Note that there is a third exit option, namely os._exit, which exits without calling cleanup handlers, flushing stdio buffers, etc. (and which should normally only be used in the child process after a fork()).

Playing sound notifications using Javascript?

Using the html5 audio tag and jquery:

// appending HTML5 Audio Tag in HTML Body
$('<audio id="chatAudio">
    <source src="notify.ogg" type="audio/ogg">
    <source src="notify.mp3" type="audio/mpeg">
</audio>').appendTo('body');

// play sound
$('#chatAudio')[0].play();

Code from here.

In my implementation I added the audio embed directly into the HTML without jquery append.

Creating object with dynamic keys

In the new ES2015 standard for JavaScript (formerly called ES6), objects can be created with computed keys: Object Initializer spec.

The syntax is:

var obj = {
  [myKey]: value,
}

If applied to the OP's scenario, it would turn into:

stuff = function (thing, callback) {
  var inputs  = $('div.quantity > input').map(function(){
    return {
      [this.attr('name')]: this.attr('value'),
    };
  }) 

  callback(null, inputs);
}

Note: A transpiler is still required for browser compatiblity.

Using Babel or Google's traceur, it is possible to use this syntax today.

In earlier JavaScript specifications (ES5 and below), the key in an object literal is always interpreted literally, as a string.

To use a "dynamic" key, you have to use bracket notation:

var obj = {};
obj[myKey] = value;

In your case:

stuff = function (thing, callback) {
  var inputs  = $('div.quantity > input').map(function(){
    var key   = this.attr('name')
     ,  value = this.attr('value')
     ,  ret   = {};

     ret[key] = value;
     return ret;
  }) 

  callback(null, inputs);
}

jquery click event not firing?

I was wasting my time on this for hours. Fortunately, I found the solution. If you are using bootstrap admin templates (AdminLTE), this problem may show up. Thing is we have to use adminLTE framework plugins.

example: ifChecked event:

$('input').on('ifChecked', function(event){
   alert(event.type + ' callback');
});

For more information click here.

Hope it helps you too.

Webfont Smoothing and Antialiasing in Firefox and Opera

As Opera is powered by Blink since Version 15.0 -webkit-font-smoothing: antialiased does also work on Opera.

Firefox has finally added a property to enable grayscaled antialiasing. After a long discussion it will be available in Version 25 with another syntax, which points out that this property only works on OS X.

-moz-osx-font-smoothing: grayscale;

This should fix blurry icon fonts or light text on dark backgrounds.

.font-smoothing {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

You may read my post about font rendering on OSX which includes a Sass mixin to handle both properties.

App.Config file in console application C#

For .NET Core, add System.Configuration.ConfigurationManager from NuGet manager.
And read appSetting from App.config

<appSettings>
  <add key="appSetting1" value="1000" />
</appSettings>

Add System.Configuration.ConfigurationManager from NuGet Manager

enter image description here

ConfigurationManager.AppSettings.Get("appSetting1")

How to control size of list-style-type disc in CSS?

Instead of using position: absolute, text-indent can be used to solve the "inside" problem:

li {
    list-style: inherit;
    margin: 0 0 4px 9px;
    text-indent: -9px;
}
li:before {
    content: "· ";
}

http://jsfiddle.net/poselab/zEMLG/

Using node.js as a simple web server

Step1 (inside command prompt [I hope you cd TO YOUR FOLDER]) : npm install express

Step 2: Create a file server.js

var fs = require("fs");
var host = "127.0.0.1";
var port = 1337;
var express = require("express");

var app = express();
app.use(express.static(__dirname + "/public")); //use static files in ROOT/public folder

app.get("/", function(request, response){ //root dir
    response.send("Hello!!");
});

app.listen(port, host);

Please note, you should add WATCHFILE (or use nodemon) too. Above code is only for a simple connection server.

STEP 3: node server.js or nodemon server.js

There is now more easy method if you just want host simple HTTP server. npm install -g http-server

and open our directory and type http-server

https://www.npmjs.org/package/http-server

How to prevent scanf causing a buffer overflow in C?

Directly using scanf(3) and its variants poses a number of problems. Typically, users and non-interactive use cases are defined in terms of lines of input. It's rare to see a case where, if enough objects are not found, more lines will solve the problem, yet that's the default mode for scanf. (If a user didn't know to enter a number on the first line, a second and third line will probably not help.)

At least if you fgets(3) you know how many input lines your program will need, and you won't have any buffer overflows...

How do I specify different layouts for portrait and landscape orientations?

I think the easiest way in the latest Android versions is by going to Design mode of an XML (not Text).

Then from the menu, select option - Create Landscape Variation. This will create a landscape xml without any hassle in a few seconds. The latest Android Studio version allows you to create a landscape view right away.

enter image description here

I hope this works for you.

What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?

Use a combination of VPTEST(D, W, B) and PSRLDQ instructions to focus in on the byte containing the most significant bit as shown below using an emulation of these instructions in Perl found at:

https://github.com/philiprbrenan/SimdAvx512

if (1) {                                                                        #TpositionOfMostSignificantBitIn64
  my @m = (                                                                     # Test strings
#B0       1       2       3       4       5       6       7
#b0123456701234567012345670123456701234567012345670123456701234567
 '0000000000000000000000000000000000000000000000000000000000000000',
 '0000000000000000000000000000000000000000000000000000000000000001',
 '0000000000000000000000000000000000000000000000000000000000000010',
 '0000000000000000000000000000000000000000000000000000000000000111',
 '0000000000000000000000000000000000000000000000000000001010010000',
 '0000000000000000000000000000000000001000000001100100001010010000',
 '0000000000000000000001001000010000000000000001100100001010010000',
 '0000000000000000100000000000000100000000000001100100001010010000',
 '1000000000000000100000000000000100000000000001100100001010010000',
);
  my @n = (0, 1, 2, 3, 10, 28, 43, 48, 64);                                     # Expected positions of msb

  sub positionOfMostSignificantBitIn64($)                                       # Find the position of the most significant bit in a string of 64 bits starting from 1 for the least significant bit or return 0 if the input field is all zeros
   {my ($s64) = @_;                                                             # String of 64 bits

    my $N = 128;                                                                # 128 bit operations
    my $f = 0;                                                                  # Position of first bit set
    my $x = '0'x$N;                                                             # Double Quad Word set to 0
    my $s = substr $x.$s64, -$N;                                                # 128 bit area needed

    substr(VPTESTMD($s, $s), -2, 1) eq '1' ? ($s = PSRLDQ $s, 4) : ($f += 32);  # Test 2 dwords
    substr(VPTESTMW($s, $s), -2, 1) eq '1' ? ($s = PSRLDQ $s, 2) : ($f += 16);  # Test 2 words
    substr(VPTESTMB($s, $s), -2, 1) eq '1' ? ($s = PSRLDQ $s, 1) : ($f +=  8);  # Test 2 bytes

    $s = substr($s, -8);                                                        # Last byte remaining

    $s < $_ ? ++$f : last for                                                   # Search remaing byte
     (qw(10000000 01000000 00100000 00010000
         00001000 00000100 00000010 00000001));

    64 - $f                                                                     # Position of first bit set
   }

  ok $n[$_] eq positionOfMostSignificantBitIn64 $m[$_] for keys @m              # Test
 }

How do I join two SQLite tables in my Android application?

In addition to @pawelzieba's answer, which definitely is correct, to join two tables, while you can use an INNER JOIN like this 

SELECT * FROM expense INNER JOIN refuel
ON exp_id = expense_id
WHERE refuel_id = 1

via raw query like this - 

String rawQuery = "SELECT * FROM " + RefuelTable.TABLE_NAME + " INNER JOIN " + ExpenseTable.TABLE_NAME
        + " ON " + RefuelTable.EXP_ID + " = " + ExpenseTable.ID
        + " WHERE " + RefuelTable.ID + " = " +  id;
Cursor c = db.rawQuery(
        rawQuery,
        null
);

because of SQLite's backward compatible support of the primitive way of querying, we turn that command into this - 

SELECT *
FROM expense, refuel
WHERE exp_id = expense_id AND refuel_id = 1

and hence be able to take advanatage of the SQLiteDatabase.query() helper method 

Cursor c = db.query(
        RefuelTable.TABLE_NAME + " , " + ExpenseTable.TABLE_NAME,
        Utils.concat(RefuelTable.PROJECTION, ExpenseTable.PROJECTION),
        RefuelTable.EXP_ID + " = " + ExpenseTable.ID + " AND " + RefuelTable.ID + " = " +  id,
        null,
        null,
        null,
        null
);

For a detailed blog post check this http://blog.championswimmer.in/2015/12/doing-a-table-join-in-android-without-using-rawquery

How to comment multiple lines with space or indent

Might just be for Visual Studio '15, if you right-click on source code, there's an option for insert comment

This puts summary tags around your comment section, but it does give the indentation that you want.

Generating a random password in php

Quick One. Simple, clean and consistent format if that is what you want

$pw = chr(mt_rand(97,122)).mt_rand(0,9).chr(mt_rand(97,122)).mt_rand(10,99).chr(mt_rand(97,122)).mt_rand(100,999);

Convert an integer to an array of digits

Use:

public static void main(String[] args)
{
    int num = 1234567;
    int[] digits = Integer.toString(num).chars().map(c -> c-'0').toArray();
    for(int d : digits)
        System.out.print(d);
}

The main idea is

  1. Convert the int to its String value

    Integer.toString(num);

  2. Get a stream of int that represents the ASCII value of each char(~digit) composing the String version of our integer

    Integer.toString(num).chars();

  3. Convert the ASCII value of each character to its value. To get the actual int value of a character, we have to subtract the ASCII code value of the character '0' from the ASCII code of the actual character. To get all the digits of our number, this operation has to be applied on each character (corresponding to the digit) composing the string equivalent of our number which is done by applying the map function below to our IntStream.

    Integer.toString(num).chars().map(c -> c-'0');

  4. Convert the stream of int to an array of int using toArray()

     Integer.toString(num).chars().map(c -> c-'0').toArray();

Swift - how to make custom header for UITableView?

I have had some problems in Swift 5 with this. When using this function I had a wrong alignment with the header cell:

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
     let headerCell = tableView.dequeueReusableCell(withIdentifier: "customTableCell") as! CustomTableCell
     return headerCell
}

The cell view was shown with a bad alignment and the top part of the tableview was shown. So I had to make some tweak like this:

func tableView(_ tableView: UITableView, viewForHeaderInSection section: Int) -> UIView? {
     let headerView = UIView.init(frame: CGRect(x: 0, y: 0, width: tableView.frame.size.width, height: 90))
     let headerCell = tableView.dequeueReusableCell(withIdentifier: "YOUR_CELL_IDENTIFIER")
     headerCell?.frame = headerView.bounds
     headerView.addSubview(headerCell!)
     return headerView
 }

I am having this problem in Swift 5 and Xcode 12.0.1, I don't know if it is just a problem for me or it is a bug. Hope it helps ! I have lost a morning...

CSS: How can I set image size relative to parent height?

Use max-width property of CSS, like this :

img{
  max-width:100%;
}

What is the difference between CHARACTER VARYING and VARCHAR in PostgreSQL?

The only difference is that CHARACTER VARYING is more human friendly than VARCHAR

Using jQuery to test if an input has focus

CSS:

.focus {
    border-color:red;
}

JQuery:

  $(document).ready(function() {

    $('input').blur(function() {
        $('input').removeClass("focus");
      })
      .focus(function() {
        $(this).addClass("focus")
      });
  });

a page can have only one server-side form tag

Use only one server side form tag.

Check your Master page for <form runat="server"> - there should be only one.

Why do you need more than one?

Flatten an irregular list of lists

Here's a simple function that flattens lists of arbitrary depth. No recursion, to avoid stack overflow.

from copy import deepcopy

def flatten_list(nested_list):
    """Flatten an arbitrarily nested list, without recursion (to avoid
    stack overflows). Returns a new list, the original list is unchanged.

    >> list(flatten_list([1, 2, 3, [4], [], [[[[[[[[[5]]]]]]]]]]))
    [1, 2, 3, 4, 5]
    >> list(flatten_list([[1, 2], 3]))
    [1, 2, 3]

    """
    nested_list = deepcopy(nested_list)

    while nested_list:
        sublist = nested_list.pop(0)

        if isinstance(sublist, list):
            nested_list = sublist + nested_list
        else:
            yield sublist

dyld: Library not loaded: /usr/local/opt/openssl/lib/libssl.1.0.0.dylib

I spent a lot of time trying all of the above, and nothing seemed to solve. Then I resorted the reinstalling ruby, and 2 minutes later the problem entirely vanished.

I hope this saves something else some time.

Can I install/update WordPress plugins without providing FTP access?

Execute the following code in terminal

sudo chown -R www-data /var/www

For further detail visit Wordpress on Ubuntu install plugins without FTP access

SOAP PHP fault parsing WSDL: failed to load external entity?

If anyone has the same problem, one possible solution is to set the bindto stream context configuration parameter (assuming you're connecting from 11.22.33.44 to 55.66.77.88):

$context = [
    'socket' => [
        'bindto' => '55.66.77.88'
    ]
];

$options = [
    'soapVersion' => SOAP_1_1,
    'stream_context' => stream_context_create($context)
];

$client = new Client('11.22.33.44', $options);

Bootstrap carousel width and height

I recommend the following for Bootstrap 3

.carousel-inner > .item > img,
.carousel-inner > .item > a > img {
  min-height: 500px;    /* Set slide height here */

}

Trying to get property of non-object MySQLi result

I think thats not the reason everybody told above. There is something wrong in your code, maybe miss spelling or mismatching with the database column names. If mysqli query gets no result then it will return false, so that it is not a object - is a wrong idea. Everything works fine. it returns 1 or 0 if query have result or not.

So, my suggestion is check your variable names and table column names or any other misspelling.

Oracle Trigger ORA-04098: trigger is invalid and failed re-validation

Cause: A trigger was attempted to be retrieved for execution and was found to be invalid. This also means that compilation/authorization failed for the trigger.

Action: Options are to resolve the compilation/authorization errors, disable the trigger, or drop the trigger.

Syntax

ALTER TRIGGER trigger Name DISABLE;

ALTER TRIGGER trigger_Name ENABLE;

How do you convert a DataTable into a generic list?

 
lPerson = dt.AsEnumerable().Select(s => new Person()
        {
            Name = s.Field<string>("Name"),
            SurName = s.Field<string>("SurName"),
            Age = s.Field<int>("Age"),
            InsertDate = s.Field<DateTime>("InsertDate")
        }).ToList();

Link to working DotNetFiddle Example

using System;
using System.Collections.Generic;   
using System.Data;
using System.Linq;
using System.Data.DataSetExtensions;

public static void Main()
{
    DataTable dt = new DataTable();
    dt.Columns.Add("Name", typeof(string));
    dt.Columns.Add("SurName", typeof(string));
    dt.Columns.Add("Age", typeof(int));
    dt.Columns.Add("InsertDate", typeof(DateTime));

    var row1= dt.NewRow();
    row1["Name"] = "Adam";
    row1["SurName"] = "Adam";
    row1["Age"] = 20;
    row1["InsertDate"] = new DateTime(2020, 1, 1);
    dt.Rows.Add(row1);

    var row2 = dt.NewRow();
    row2["Name"] = "John";
    row2["SurName"] = "Smith";
    row2["Age"] = 25;
    row2["InsertDate"] = new DateTime(2020, 3, 12);
    dt.Rows.Add(row2);

    var row3 = dt.NewRow();
    row3["Name"] = "Jack";
    row3["SurName"] = "Strong";
    row3["Age"] = 32;
    row3["InsertDate"] = new DateTime(2020, 5, 20);
    dt.Rows.Add(row3);

    List<Person> lPerson = new List<Person>();
    lPerson = dt.AsEnumerable().Select(s => new Person()
    {
        Name = s.Field<string>("Name"),
        SurName = s.Field<string>("SurName"),
        Age = s.Field<int>("Age"),
        InsertDate = s.Field<DateTime>("InsertDate")
    }).ToList();

    foreach(Person pers in lPerson)
    {
        Console.WriteLine("{0} {1} {2} {3}", pers.Name, pers.SurName, pers.Age, pers.InsertDate);
    }
}   

public class Person
{
    public string Name { get; set; }
    public string SurName { get; set; }
    public int Age { get; set; }
    public DateTime InsertDate { get; set; }
}

}

What is the Swift equivalent to Objective-C's "@synchronized"?

Why make it difficult and hassle with locks? Use Dispatch Barriers.

A dispatch barrier creates a synchronization point within a concurrent queue.

While it’s running, no other block on the queue is allowed to run, even if it’s concurrent and other cores are available.

If that sounds like an exclusive (write) lock, it is. Non-barrier blocks can be thought of as shared (read) locks.

As long as all access to the resource is performed through the queue, barriers provide very cheap synchronization.

How do I execute a MS SQL Server stored procedure in java/jsp, returning table data?

Thank to Brian for the code. I was trying to connect to the sql server with {call spname(?,?)} and I got errors, but when I change my code to exec sp... it works very well.

I post my code in hope this helps others with problems like mine:

ResultSet rs = null;
PreparedStatement cs=null;
Connection conn=getJNDIConnection();

try {
    cs=conn.prepareStatement("exec sp_name ?,?,?,?,?,?,?");
    cs.setEscapeProcessing(true);
    cs.setQueryTimeout(90);

    cs.setString(1, "valueA");

    cs.setString(2, "valueB");

    cs.setString(3, "0418");

    //commented, because no need to register parameters out!, I got results from the resultset. 
    //cs.registerOutParameter(1, Types.VARCHAR);
    //cs.registerOutParameter(2, Types.VARCHAR);

    rs = cs.executeQuery();
    ArrayList<ObjectX> listaObjectX = new ArrayList<ObjectX>();
    while (rs.next()) {

        ObjectX to = new ObjectX();
        to.setFecha(rs.getString(1));
        to.setRefId(rs.getString(2));
        to.setRefNombre(rs.getString(3));
        to.setUrl(rs.getString(4));

        listaObjectX.add(to);

    }
    return listaObjectX;
     } catch (SQLException se) {
        System.out.println("Error al ejecutar SQL"+ se.getMessage());
        se.printStackTrace();
        throw new IllegalArgumentException("Error al ejecutar SQL: " + se.getMessage());

    } finally {

        try {

            rs.close();
            cs.close();
          con.close();

        } catch (SQLException ex) {
            ex.printStackTrace();
        }
    }

How to set a header for a HTTP GET request, and trigger file download?

Pure jQuery.

$.ajax({
  type: "GET",
  url: "https://example.com/file",
  headers: {
    'Authorization': 'Bearer eyJraWQiFUDA.......TZxX1MGDGyg'
  },
  xhrFields: {
    responseType: 'blob'
  },
  success: function (blob) {
    var windowUrl = window.URL || window.webkitURL;
    var url = windowUrl.createObjectURL(blob);
    var anchor = document.createElement('a');
    anchor.href = url;
    anchor.download = 'filename.zip';
    anchor.click();
    anchor.parentNode.removeChild(anchor);
    windowUrl.revokeObjectURL(url);
  },
  error: function (error) {
    console.log(error);
  }
});

Set height of chart in Chart.js

You should use html height attribute for the canvas element as:

<div class="chart">
    <canvas id="myChart" height="100"></canvas>
</div>

How to Remove the last char of String in C#?

 
YourString = YourString.Remove(YourString.Length - 1);

How to setup Tomcat server in Netbeans?

If TomCat is install. Perhaps it is not installed Java EE. Services-> plug-ins-> additional plug-ins-> in the search dial tomcat. and install the module java ee. then in the services, servers, add the tomcat server.

Android emulator doesn't take keyboard input - SDK tools rev 20

Restarting the emulator helps sometimes when typing is unavailable - despite keyboard input being enabled for your Android Virtual Device.

geom_smooth() what are the methods available?

The se argument from the example also isn't in the help or online documentation.

When 'se' in geom_smooth is set 'FALSE', the error shading region is not visible

Rotate image with javascript

CSS can be applied and you will have to set transform-origin correctly to get the applied transformation in the way you want

See the fiddle:

http://jsfiddle.net/OMS_/gkrsz/

Main code:

/* assuming that the image's height is 70px */

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

    transform-origin: 35px 35px;
    -webkit-transform-origin: 35px 35px;
    -moz-transform-origin: 35px 35px;
    -ms-transform-origin: 35px 35px;
}

jQuery and JS:

$(img)
    .css('transform-origin-x', imgWidth / 2)
    .css('transform-origin-y', imgHeight / 2);

// By calculating the height and width of the image in the load function

// $(img).css('transform-origin', (imgWidth / 2) + ' ' + (imgHeight / 2) );

Logic:

Divide the image's height by 2. The transform-x and transform-y values should be this value

Link:

transform-origin at CSS | MDN

Non-numeric Argument to Binary Operator Error in R

Because your question is phrased regarding your error message and not whatever your function is trying to accomplish, I will address the error.

- is the 'binary operator' your error is referencing, and either CurrentDay or MA (or both) are non-numeric.

A binary operation is a calculation that takes two values (operands) and produces another value (see wikipedia for more). + is one such operator: "1 + 1" takes two operands (1 and 1) and produces another value (2). Note that the produced value isn't necessarily different from the operands (e.g., 1 + 0 = 1).

R only knows how to apply + (and other binary operators, such as -) to numeric arguments:

> 1 + 1
[1] 2
> 1 + 'one'
Error in 1 + "one" : non-numeric argument to binary operator

When you see that error message, it means that you are (or the function you're calling is) trying to perform a binary operation with something that isn't a number.

EDIT:

Your error lies in the use of [ instead of [[. Because Day is a list, subsetting with [ will return a list, not a numeric vector. [[, however, returns an object of the class of the item contained in the list:

> Day <- Transaction(1, 2)["b"]
> class(Day)
[1] "list"
> Day + 1
Error in Day + 1 : non-numeric argument to binary operator

> Day2 <- Transaction(1, 2)[["b"]]
> class(Day2)
[1] "numeric"
> Day2 + 1
[1] 3

Transaction, as you've defined it, returns a list of two vectors. Above, Day is a list contain one vector. Day2, however, is simply a vector.

403 - Forbidden: Access is denied. ASP.Net MVC

In addition to the answers above, you may also get that error when you have Windows Authenticaton set and :

  • IIS is pointing to an empty folder.
  • You do not have a default document set.

jQuery slide left and show

You can add new function to your jQuery library by adding these line on your own script file and you can easily use fadeSlideRight() and fadeSlideLeft().

Note: you can change width of animation as you like instance of 750px.

$.fn.fadeSlideRight = function(speed,fn) {
    return $(this).animate({
        'opacity' : 1,
        'width' : '750px'
    },speed || 400, function() {
        $.isFunction(fn) && fn.call(this);
    });
}

$.fn.fadeSlideLeft = function(speed,fn) {
    return $(this).animate({
        'opacity' : 0,
        'width' : '0px'
    },speed || 400,function() {
        $.isFunction(fn) && fn.call(this);
    });
}

Change label text using JavaScript

Try this:

<label id="lbltipAddedComment"></label>
<script type="text/javascript"> 
      document.getElementById('<%= lbltipAddedComment.ClientID %>').innerHTML = 'your tip has been submitted!';
</script>

jQuery autocomplete tagging plug-in like StackOverflow's input tags?

This originally answered a supplemental question about the wisdom of downloading jQuery versus accessing it via a CDN, which is no longer present...

To answer the thing about Google. I have moved over to accessing JQuery and most other of these sorts of libraries via the corresponding CDN in my sites.

As more people do this means that it's more likely to be cached on user's machines, so my vote goes for good idea.

In the five years since I first offered this, it has become common wisdom.

Import a module from a relative path

 
import os
import sys
lib_path = os.path.abspath(os.path.join(__file__, '..', '..', '..', 'lib'))
sys.path.append(lib_path)

import mymodule

Ansible: get current target host's IP address

Plain ansible_default_ipv4.address might not be what you think in some cases, use:

ansible_default_ipv4.address|default(ansible_all_ipv4_addresses[0])

Is there an operator to calculate percentage in Python?

use of %

def percent(expression):
    if "%" in expression:
        expression = expression.replace("%","/100")
    return eval(expression)

>>> percent("1500*20%")
300.0

Somthing simple

>>> p = lambda x: x/100
>>> p(20)
0.2
>>> 100*p(20)
20.0
>>>

Merge some list items in a Python List

On what basis should the merging take place? Your question is rather vague. Also, I assume a, b, ..., f are supposed to be strings, that is, 'a', 'b', ..., 'f'.

>>> x = ['a', 'b', 'c', 'd', 'e', 'f', 'g']
>>> x[3:6] = [''.join(x[3:6])]
>>> x
['a', 'b', 'c', 'def', 'g']

Check out the documentation on sequence types, specifically on mutable sequence types. And perhaps also on string methods.

How to write JUnit test with Spring Autowire?

I've done it with two annotations for test class: @RunWith(SpringRunner.class) and @SpringBootTest. Example:

@RunWith(SpringRunner.class )
@SpringBootTest
public class ProtocolTransactionServiceTest {

    @Autowired
    private ProtocolTransactionService protocolTransactionService;
}

@SpringBootTest loads the whole context, which was OK in my case.

How to avoid "StaleElementReferenceException" in Selenium?

Kenny's solution is good, however it can be written in a more elegant way

new WebDriverWait(driver, timeout)
        .ignoring(StaleElementReferenceException.class)
        .until((WebDriver d) -> {
            d.findElement(By.id("checkoutLink")).click();
            return true;
        });

Or also:

new WebDriverWait(driver, timeout).ignoring(StaleElementReferenceException.class).until(ExpectedConditions.elementToBeClickable(By.id("checkoutLink")));
driver.findElement(By.id("checkoutLink")).click();

But anyway, best solution is to rely on Selenide library, it handles this kind of things and more. (instead of element references it handles proxies so you never have to deal with stale elements, which can be quite difficult). Selenide

How to list active / open connections in Oracle?

 
Select count(1) From V$session
where status='ACTIVE'
/

What's the difference between TRUNCATE and DELETE in SQL

All good answers, to which I must add:

Since TRUNCATE TABLE is a DDL (Data Defination Language), not a DML (Data Manipulation Langauge) command, the Delete Triggers do not run.

How to round an image with Glide library?

Roman Samoylenko's answer was correct except the function has changed. The correct answer is

Glide.with(context)
                .load(yourImage)
                .apply(RequestOptions.circleCropTransform())
                .into(imageView);

Can gcc output C code after preprocessing?

I'm using gcc as a preprocessor (for html files.) It does just what you want. It expands "#--" directives, then outputs a readable file. (NONE of the other C/HTML preprocessors I've tried do this- they concatenate lines, choke on special characters, etc.) Asuming you have gcc installed, the command line is:

gcc -E -x c -P -C -traditional-cpp code_before.cpp > code_after.cpp

(Doesn't have to be 'cpp'.) There's an excellent description of this usage at http://www.cs.tut.fi/~jkorpela/html/cpre.html.

The "-traditional-cpp" preserves whitespace & tabs.

Unable to connect with remote debugger

In my case the issue was that the emulator was making a request to:

http://10.0.2.2:8081/debugger-ui

instead of:

http://localhost:8081/debugger-ui and the request was failing.

To solve the issue: Before enabling remote debugging on your emulator, open http://localhost:8081/debugger-ui in chrome. Then enable remote debugging and go back to the chrome page where you should see your console logs.

Using scanner.nextLine()

Rather than placing an extra scanner.nextLine() each time you want to read something, since it seems you want to accept each input on a new line, you might want to instead changing the delimiter to actually match only newlines (instead of any whitespace, as is the default)

import java.util.Scanner;

class ScannerTest {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        scanner.useDelimiter("\\n");

        System.out.print("Enter an index: ");
        int index = scanner.nextInt();

        System.out.print("Enter a sentence: ");
        String sentence = scanner.next();

        System.out.println("\nYour sentence: " + sentence);
        System.out.println("Your index: " + index);
    }
}

Thus, to read a line of input, you only need scanner.next() that has the same behavior delimiter-wise of next{Int, Double, ...}

The difference with the "nextLine() every time" approach, is that the latter will accept, as an index also <space>3, 3<space> and 3<space>whatever while the former only accepts 3 on a line on its own

WebApi's {"message":"an error has occurred"} on IIS7, not in IIS Express

I always come to this question when I hit an error in the test environment and remember, "I've done this before, but I can do it straight in the web.config without having to modify code and re-deploy to the test environment, but it takes 2 changes... what was it again?"

For future reference

<system.web>
   <customErrors mode="Off"></customErrors>
</system.web>

AND

<system.webServer>
  <httpErrors errorMode="Detailed" existingResponse="PassThrough"></httpErrors>
</system.webServer>

How to Get the Query Executed in Laravel 5? DB::getQueryLog() Returning Empty Array

For laravel 5.8 you just add dd or dump.

Ex:

DB::table('users')->where('votes', '>', 100)->dd();

or

DB::table('users')->where('votes', '>', 100)->dump();

reference: https://laravel.com/docs/5.8/queries#debugging

Using multiprocessing.Process with a maximum number of simultaneous processes

I think Semaphore is what you are looking for, it will block the main process after counting down to 0. Sample code:

from multiprocessing import Process
from multiprocessing import Semaphore
import time

def f(name, sema):
    print('process {} starting doing business'.format(name))
    # simulate a time-consuming task by sleeping
    time.sleep(5)
    # `release` will add 1 to `sema`, allowing other 
    # processes blocked on it to continue
    sema.release()

if __name__ == '__main__':
    concurrency = 20
    total_task_num = 1000
    sema = Semaphore(concurrency)
    all_processes = []
    for i in range(total_task_num):
        # once 20 processes are running, the following `acquire` call
        # will block the main process since `sema` has been reduced
        # to 0. This loop will continue only after one or more 
        # previously created processes complete.
        sema.acquire()
        p = Process(target=f, args=(i, sema))
        all_processes.append(p)
        p.start()

    # inside main process, wait for all processes to finish
    for p in all_processes:
        p.join()

The following code is more structured since it acquires and releases sema in the same function. However, it will consume too much resources if total_task_num is very large:

from multiprocessing import Process
from multiprocessing import Semaphore
import time

def f(name, sema):
    print('process {} starting doing business'.format(name))
    # `sema` is acquired and released in the same
    # block of code here, making code more readable,
    # but may lead to problem.
    sema.acquire()
    time.sleep(5)
    sema.release()

if __name__ == '__main__':
    concurrency = 20
    total_task_num = 1000
    sema = Semaphore(concurrency)
    all_processes = []
    for i in range(total_task_num):
        p = Process(target=f, args=(i, sema))
        all_processes.append(p)
        # the following line won't block after 20 processes
        # have been created and running, instead it will carry 
        # on until all 1000 processes are created.
        p.start()

    # inside main process, wait for all processes to finish
    for p in all_processes:
        p.join()

The above code will create total_task_num processes but only concurrency processes will be running while other processes are blocked, consuming precious system resources.

Sorting Characters Of A C++ String

There is a sorting algorithm in the standard library, in the header <algorithm>. It sorts inplace, so if you do the following, your original word will become sorted.

std::sort(word.begin(), word.end());

If you don't want to lose the original, make a copy first.

std::string sortedWord = word;
std::sort(sortedWord.begin(), sortedWord.end());

How to resolve symbolic links in a shell script

 
readlink -e [filepath]

seems to be exactly what you're asking for - it accepts an arbirary path, resolves all symlinks, and returns the "real" path - and it's "standard *nix" that likely all systems already have

Error starting Tomcat from NetBeans - '127.0.0.1*' is not recognized as an internal or external command

I didnt try Sumama Waheed's answer but what worked for me was replacing the bin/catalina.jar with a working jar (I disposed of an older tomcat) and after adding in NetBeans, I put the original catalina.jar again.

How to check if running as root in a bash script

try the following code:

if [ "$(id -u)" != "0" ]; then
    echo "Sorry, you are not root."
    exit 1
fi

OR

if [ `id -u` != "0" ]; then
    echo "Sorry, you are not root."
    exit 1
fi

How to find out the username and password for mysql database

If you forget your password for SQL plus 10g then follow the steps :

  1. START
  2. Type RUN in the search box
  3. Type 'cnc' in the box captioned as OPEN and a black box will appear 4.There will be some text already in the box. (C:\Users\admin>) Just beside that start typing 'sqlplus/nolog' press ENTER key
  4. On the next line type 'conn sys/change_on_install as sysdba' (press ENTER) 6.(in the next line after sql-> type) 'alter user scott account unlock' .
  5. Now open your slpplus and type user name as 'scott' and password as 'tiger'.

If it asks your old password then type the one you have given while installing.

Why is visible="false" not working for a plain html table?

If you want use it, use runat="server" for that table. After that use tablename.visible=False in server side code.

Reading integers from binary file in Python

When you read from a binary file, a data type called bytes is used. This is a bit like list or tuple, except it can only store integers from 0 to 255.

Try:

file_size = fin.read(4)
file_size0 = file_size[0]
file_size1 = file_size[1]
file_size2 = file_size[2]
file_size3 = file_size[3]

Or:

file_size = list(fin.read(4))

Instead of:

file_size = int(fin.read(4))

how to use Blob datatype in Postgres

I think this is the most comprehensive answer on the PostgreSQL wiki itself: https://wiki.postgresql.org/wiki/BinaryFilesInDB

Read the part with the title 'What is the best way to store the files in the Database?'

Facebook Like-Button - hide count?

Accepted answer is good, but be careful with multilingual pages. The text differ in length:

English: Like

Dutch: Vind ik leuk

German: Gefällt mir

Just a heads up.

Parse JSON file using GSON

I'm using gson 2.2.3

public class Main {

/**
 * @param args
 * @throws IOException 
 */
public static void main(String[] args) throws IOException {

    JsonReader jsonReader = new JsonReader(new FileReader("jsonFile.json"));

    jsonReader.beginObject();

    while (jsonReader.hasNext()) {

    String name = jsonReader.nextName();
        if (name.equals("descriptor")) {
             readApp(jsonReader);

        }
    }

   jsonReader.endObject();
   jsonReader.close();

}

public static void readApp(JsonReader jsonReader) throws IOException{
    jsonReader.beginObject();
     while (jsonReader.hasNext()) {
         String name = jsonReader.nextName();
         System.out.println(name);
         if (name.contains("app")){
             jsonReader.beginObject();
             while (jsonReader.hasNext()) {
                 String n = jsonReader.nextName();
                 if (n.equals("name")){
                     System.out.println(jsonReader.nextString());
                 }
                 if (n.equals("age")){
                     System.out.println(jsonReader.nextInt());
                 }
                 if (n.equals("messages")){
                     jsonReader.beginArray();
                     while  (jsonReader.hasNext()) {
                          System.out.println(jsonReader.nextString());
                     }
                     jsonReader.endArray();
                 }
             }
             jsonReader.endObject();
         }

     }
     jsonReader.endObject();
}
}

Which is a better way to check if an array has more than one element?

I assume $arr is an array then this is what you are looking for

if ( sizeof($arr) > 1) ...

How do I setup the InternetExplorerDriver so it works

 
public class NavigateUsingAllBrowsers {


public static void main(String[] args) {

WebDriver driverFF= new FirefoxDriver();
driverFF.navigate().to("http://www.firefox.com");


File file =new File("C:/Users/mkv/workspace/ServerDrivers/IEDriverServer.exe");
System.setProperty("webdriver.ie.driver", file.getAbsolutePath());
WebDriver driverIE=new InternetExplorerDriver();
driverIE.navigate().to("http://www.msn.com");

// Download Chrome Driver from http://code.google.com/p/chromedriver/downloads/list

file =new File("C:/Users/mkv/workspace/ServerDrivers/ChromeDriver.exe");
System.setProperty("webdriver.chrome.driver", file.getAbsolutePath());
WebDriver driverChrome=new ChromeDriver();
driverChrome.navigate().to("http://www.chrome.com");

}

}

Obtain form input fields using jQuery?

 
$('#myForm').bind('submit', function () {
  var elements = this.elements;
});

The elements variable will contain all the inputs, selects, textareas and fieldsets within the form.

How to download Visual Studio Community Edition 2015 (not 2017)

The "official" way to get the vs2015 is to go to https://my.visualstudio.com/ ; join the " Visual Studio Dev Essentials" and then search the relevant file to download https://my.visualstudio.com/Downloads?q=Visual%20Studio%202015%20with%20Update%203

In Android, how do I set margins in dp programmatically?

Simple Kotlin Extension Solutions

Set all/any side independently:

fun View.setMargin(left: Int? = null, top: Int? = null, right: Int? = null, bottom: Int? = null) {
    val params = (layoutParams as? MarginLayoutParams)
    params?.setMargins(
            left ?: params.leftMargin,
            top ?: params.topMargin,
            right ?: params.rightMargin,
            bottom ?: params.bottomMargin)
    layoutParams = params
}

myView.setMargin(10, 5, 10, 5)
// or just any subset
myView.setMargin(right = 10, bottom = 5)

Directly refer to a resource values:

fun View.setMarginRes(@DimenRes left: Int? = null, @DimenRes top: Int? = null, @DimenRes right: Int? = null, @DimenRes bottom: Int? = null) {
    setMargin(
            if (left == null) null else resources.getDimensionPixelSize(left),
            if (top == null) null else resources.getDimensionPixelSize(top),
            if (right == null) null else resources.getDimensionPixelSize(right),
            if (bottom == null) null else resources.getDimensionPixelSize(bottom),
    )
}

myView.setMarginRes(top = R.dimen.my_margin_res)

To directly set all sides equally as a property:

var View.margin: Int
    get() = throw UnsupportedOperationException("No getter for property")
    set(@Px margin) = setMargin(margin, margin, margin, margin)
   
myView.margin = 10 // px

// or as res
var View.marginRes: Int
    get() = throw UnsupportedOperationException("No getter for property")
    set(@DimenRes marginRes) {
        margin = resources.getDimensionPixelSize(marginRes)
    }

myView.marginRes = R.dimen.my_margin_res

To directly set a specific side, you can create a property extension like this:

var View.leftMargin
    get() = marginLeft
    set(@Px leftMargin) = setMargin(left = leftMargin)

var View.leftMarginRes: Int
    get() = throw UnsupportedOperationException("No getter for property")
    set(@DimenRes leftMarginRes) {
        leftMargin = resources.getDimensionPixelSize(leftMarginRes)
    }

This allows you to make horizontal or vertical variants as well:

var View.horizontalMargin
    get() = throw UnsupportedOperationException("No getter for property")
    set(@Px horizontalMargin) = setMargin(left = horizontalMargin, right = horizontalMargin)

var View.horizontalMarginRes: Int
    get() = throw UnsupportedOperationException("No getter for property")
    set(@DimenRes horizontalMarginRes) {
        horizontalMargin = resources.getDimensionPixelSize(horizontalMarginRes)
    }

NOTE: If margin is failing to set, you may too soon before render, meaning params == null. Try wrapping the modification with myView.post{ margin = 10 }

I want to remove double quotes from a String

If the string is guaranteed to have one quote (or any other single character) at beginning and end which you'd like to remove:

str = str.slice(1, -1);

slice has much less overhead than a regular expression.

Get element from within an iFrame

None of the other answers were working for me. I ended up creating a function within my iframe that returns the object I was looking for:

function getElementWithinIframe() {
    return document.getElementById('copy-sheet-form');
}

Then you call that function like so to retrieve the element:

var el = document.getElementById("iframeId").contentWindow.functionNameToCall();

Download file of any type in Asp.Net MVC using FileResult?

If you're using .NET Framework 4.5 then you use use the MimeMapping.GetMimeMapping(string FileName) to get the MIME-Type for your file. This is how I've used it in my action.

return File(Path.Combine(@"c:\path", fileFromDB.FileNameOnDisk), MimeMapping.GetMimeMapping(fileFromDB.FileName), fileFromDB.FileName);

Subtracting 1 day from a timestamp date

Use the INTERVAL type to it. E.g:

--yesterday
SELECT NOW() - INTERVAL '1 DAY';

--Unrelated to the question, but PostgreSQL also supports some shortcuts:
SELECT 'yesterday'::TIMESTAMP, 'tomorrow'::TIMESTAMP, 'allballs'::TIME;

Then you can do the following on your query:

SELECT 
    org_id,
    count(accounts) AS COUNT,
    ((date_at) - INTERVAL '1 DAY') AS dateat
FROM 
    sourcetable
WHERE 
    date_at <= now() - INTERVAL '130 DAYS'
GROUP BY 
    org_id,
    dateat;


TIPS

Tip 1

You can append multiple operands. E.g.: how to get last day of current month?

SELECT date_trunc('MONTH', CURRENT_DATE) + INTERVAL '1 MONTH - 1 DAY';

Tip 2

You can also create an interval using make_interval function, useful when you need to create it at runtime (not using literals):

SELECT make_interval(days => 10 + 2);
SELECT make_interval(days => 1, hours => 2);
SELECT make_interval(0, 1, 0, 5, 0, 0, 0.0);


More info:

Date/Time Functions and Operators

datatype-datetime (Especial values).

Reliable way to convert a file to a byte[]

looks good enough as a generic version. You can modify it to meet your needs, if they're specific enough.

also test for exceptions and error conditions, such as file doesn't exist or can't be read, etc.

you can also do the following to save some space:

 byte[] bytes = System.IO.File.ReadAllBytes(filename);

Multi-gradient shapes

Have you tried to overlay one gradient with a nearly-transparent opacity for the highlight on top of another image with an opaque opacity for the green gradient?

POST data to a URL in PHP

cURL-less you can use in php5

$url = 'URL';
$data = array('field1' => 'value', 'field2' => 'value');
$options = array(
        'http' => array(
        'header'  => "Content-type: application/x-www-form-urlencoded\r\n",
        'method'  => 'POST',
        'content' => http_build_query($data),
    )
);

$context  = stream_context_create($options);
$result = file_get_contents($url, false, $context);
var_dump($result);

415 Unsupported Media Type - POST json to OData service in lightswitch 2012

It looks like this issue has to do with the difference between the Content-Type and Accept headers. In HTTP, Content-Type is used in request and response payloads to convey the media type of the current payload. Accept is used in request payloads to say what media types the server may use in the response payload.

So, having a Content-Type in a request without a body (like your GET request) has no meaning. When you do a POST request, you are sending a message body, so the Content-Type does matter.

If a server is not able to process the Content-Type of the request, it will return a 415 HTTP error. (If a server is not able to satisfy any of the media types in the request Accept header, it will return a 406 error.)

In OData v3, the media type "application/json" is interpreted to mean the new JSON format ("JSON light"). If the server does not support reading JSON light, it will throw a 415 error when it sees that the incoming request is JSON light. In your payload, your request body is verbose JSON, not JSON light, so the server should be able to process your request. It just doesn't because it sees the JSON light content type.

You could fix this in one of two ways:

  1. Make the Content-Type "application/json;odata=verbose" in your POST request, or

  2. Include the DataServiceVersion header in the request and set it be less than v3. For example:

    DataServiceVersion: 2.0;

(Option 2 assumes that you aren't using any v3 features in your request payload.)

CSS Box Shadow Bottom Only

Try this 

-moz-box-shadow:0 5px 5px rgba(182, 182, 182, 0.75);
-webkit-box-shadow: 0 5px 5px rgba(182, 182, 182, 0.75);
box-shadow: 0 5px 5px rgba(182, 182, 182, 0.75);

You can see it in http://jsfiddle.net/wJ7qp/

How can I remove all objects but one from the workspace in R?

I just spent several hours hunting for the answer to a similar but slightly different question - I needed to be able to delete all objects in R (including functions) except a handful of vectors.

One way to do this:

rm(list=ls()[! ls() %in% c("a","c")])

Where the vectors that I want to keep are named 'a' and 'c'.

Hope this helps anyone searching for the same solution!

How do I define the name of image built with docker-compose

According to 3.9 version of Docker compose, you can use image: myapp:tag to specify name and tag.

version: "3.9"
services:
  webapp:
    build:
      context: .
      dockerfile: Dockerfile
    image: webapp:tag

Reference: https://docs.docker.com/compose/compose-file/compose-file-v3/

How can I test if a letter in a string is uppercase or lowercase using JavaScript?

 
if (character == character.toLowerCase())
{
  // The character is lowercase
}
else
{
  // The character is uppercase
}

How can I disable editing cells in a WPF Datagrid?

If you want to disable editing the entire grid, you can set IsReadOnly to true on the grid. If you want to disable user to add new rows, you set the property CanUserAddRows="False"

<DataGrid IsReadOnly="True" CanUserAddRows="False" />

Further more you can set IsReadOnly on individual columns to disable editing.

Vim multiline editing like in sublimetext?

if you use the "global" command, you can repeat what you can do on one online an any number of lines.

:g/<search>/.<your ex command>

example:

:g/foo/.s/bar/baz/g

The above command finds all lines that have foo, and replace all occurrences of bar on that line with baz.

:g/.*/

will do on every line