Programs & Examples On #Language extension

What programming languages can one use to develop iPhone, iPod Touch and iPad (iOS) applications?

objective-c is the primary language used.

i believe there is a mono touch framework that can be used with c#

Adobe also is working in some tools, one is this iPhone Packager which can utilize actionscript code

Angular ngClass and click event for toggling class

If you're looking for an HTML only way of doing this in angular...

<div #myDiv class="my_class" (click)="myDiv.classList.toggle('active')">
  Some content
</div>

The important bit is the #myDiv part.

It's a HTML Node reference, so you can use that variable as if it was assigned to document.querySelector('.my_class')

NOTE: this variable is scope specific, so you can use it in *ngFor statements

How should the ViewModel close the form?

Assuming your login dialog is the first window that gets created, try this inside your LoginViewModel class:

    void OnLoginResponse(bool loginSucceded)
    {
        if (loginSucceded)
        {
            Window1 window = new Window1() { DataContext = new MainWindowViewModel() };
            window.Show();

            App.Current.MainWindow.Close();
            App.Current.MainWindow = window;
        }
        else
        {
            LoginError = true;
        }
    }

How do I check out an SVN project into Eclipse as a Java project?

I had to add the .classpath too, form a java project. I made a dummy java project and looked in the workspace for this dummy java project to see what is required. I transferred the two files. profile and .claspath to my checked out, and disconnected source from my subversion server. From then on it turned to a java project from just a plain old project.

Java Compare Two Lists

public static boolean compareList(List ls1, List ls2){
    return ls1.containsAll(ls2) && ls1.size() == ls2.size() ? true :false;
     }

public static void main(String[] args) {

    ArrayList<String> one = new ArrayList<String>();
    one.add("one");
    one.add("two");
    one.add("six");

    ArrayList<String> two = new ArrayList<String>();
    two.add("one");
    two.add("six");
    two.add("two");

    System.out.println("Output1 :: " + compareList(one, two));

    two.add("ten");

    System.out.println("Output2 :: " + compareList(one, two));
  }

There is no ViewData item of type 'IEnumerable<SelectListItem>' that has the key 'xxx'

This is OK too; For example:
==> In "NumberController" file:

public ActionResult Create([Bind(Include = "NumberId,Number1,Number2,OperatorId")] Number number)
{
    if (ModelState.IsValid)
    {
        ...
        ...
        return RedirectToAction("Index");
    }
    ViewBag.OperatorId = new SelectList(db.Operators, "OperatorId", 
                                "OperatorSign", number.OperatorId);                
    return View();
}

==> In View file (Create.cshtml):

<div class="form-group">
    @Html.LabelFor(model => model.Number1, htmlAttributes: new { @class = 
                   "control-label col-md-2" })
    <div class="col-md-10">
        @Html.EditorFor(model => model.Number1, new { htmlAttributes = new { 
                        @class = "form-control" } })
        @Html.ValidationMessageFor(model => model.Number1, "", new { @class = 
                                   "text-danger" })
    </div>
</div>

Now if we remove this statement:

ViewBag.OperatorId = new SelectList(db.Operators, "OperatorId", "OperatorSign", number.OperatorId);

from back of the following statement (in our controller) :

return View();

we will see this error:

There is no ViewData item of type 'IEnumerable' that has the key 'OperatorId'.

* So be sure of the existing of these statements. *

Jquery array.push() not working

Your code alerts the current value of the dropdown for me, showing that it has properly pushed into the array.

Are you wanting to keep old values and append? You're recreating the array each time, meaning that the old value gets clobbered.

Here's some updated code:

var myarray = [];
$("#test").click(function() {
    myarray.push($("#drop").val());
    alert(myarray);
});

jsFiddle

PHP - remove all non-numeric characters from a string

Use \D to match non-digit characters.

preg_replace('~\D~', '', $str);

How can I make one python file run another?

You could use this script:

def run(runfile):
  with open(runfile,"r") as rnf:
    exec(rnf.read())

Syntax:

run("file.py")

How can I print a quotation mark in C?

you should use escape character like this:

printf("\"");

jQuery - get all divs inside a div with class ".container"

To get all divs under 'container', use the following:

$(".container>div")  //or
$(".container").children("div");

You can stipulate a specific #id instead of div to get a particular one.

You say you want a div with an 'undefined' id. if I understand you right, the following would achieve this:

$(".container>div[id=]")

Regular expression for extracting tag attributes

Although the advice not to parse HTML via regexp is valid, here's a expression that does pretty much what you asked:

/
   \G                     # start where the last match left off
   (?>                    # begin non-backtracking expression
       .*?                # *anything* until...
       <[Aa]\b            # an anchor tag
    )??                   # but look ahead to see that the rest of the expression
                          #    does not match.
    \s+                   # at least one space
    ( \p{Alpha}           # Our first capture, starting with one alpha
      \p{Alnum}*          # followed by any number of alphanumeric characters
    )                     # end capture #1
    (?: \s* = \s*         # a group starting with a '=', possibly surrounded by spaces.
        (?: (['"])        # capture a single quote character
            (.*?)         # anything else
             \2           # which ever quote character we captured before
        |   ( [^>\s'"]+ ) # any number of non-( '>', space, quote ) chars
        )                 # end group
     )?                   # attribute value was optional
/msx;

"But wait," you might say. "What about *comments?!?!" Okay, then you can replace the . in the non-backtracking section with: (It also handles CDATA sections.)

(?:[^<]|<[^!]|<![^-\[]|<!\[(?!CDATA)|<!\[CDATA\[.*?\]\]>|<!--(?:[^-]|-[^-])*-->)
  • Also if you wanted to run a substitution under Perl 5.10 (and I think PCRE), you can put \K right before the attribute name and not have to worry about capturing all the stuff you want to skip over.

How do I compare strings in GoLang?

For the Platform Independent Users or Windows users, what you can do is:

import runtime:

import (
    "runtime"
    "strings"
)

and then trim the string like this:

if runtime.GOOS == "windows" {
  input = strings.TrimRight(input, "\r\n")
} else {
  input = strings.TrimRight(input, "\n")
}

now you can compare it like that:

if strings.Compare(input, "a") == 0 {
  //....yourCode
}

This is a better approach when you're making use of STDIN on multiple platforms.

Explanation

This happens because on windows lines end with "\r\n" which is known as CRLF, but on UNIX lines end with "\n" which is known as LF and that's why we trim "\n" on unix based operating systems while we trim "\r\n" on windows.

How should I use try-with-resources with JDBC?

What about creating an additional wrapper class?

package com.naveen.research.sql;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public abstract class PreparedStatementWrapper implements AutoCloseable {

    protected PreparedStatement stat;

    public PreparedStatementWrapper(Connection con, String query, Object ... params) throws SQLException {
        this.stat = con.prepareStatement(query);
        this.prepareStatement(params);
    }

    protected abstract void prepareStatement(Object ... params) throws SQLException;

    public ResultSet executeQuery() throws SQLException {
        return this.stat.executeQuery();
    }

    public int executeUpdate() throws SQLException {
        return this.stat.executeUpdate();
    }

    @Override
    public void close() {
        try {
            this.stat.close();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}


Then in the calling class you can implement prepareStatement method as:

try (Connection con = DriverManager.getConnection(JDBC_URL, prop);
    PreparedStatementWrapper stat = new PreparedStatementWrapper(con, query,
                new Object[] { 123L, "TEST" }) {
            @Override
            protected void prepareStatement(Object... params) throws SQLException {
                stat.setLong(1, Long.class.cast(params[0]));
                stat.setString(2, String.valueOf(params[1]));
            }
        };
        ResultSet rs = stat.executeQuery();) {
    while (rs.next())
        System.out.println(String.format("%s, %s", rs.getString(2), rs.getString(1)));
} catch (SQLException e) {
    e.printStackTrace();
}

Regular expression - starting and ending with a character string

This should do it for you ^wp.*php$

Matches

wp-comments-post.php
wp.something.php
wp.php

Doesn't match

something-wp.php
wp.php.txt

The imported project "C:\Microsoft.CSharp.targets" was not found

If you are to encounter the error that says Microsoft.CSharp.Core.targets not found, these are the steps I took to correct mine:

  1. Open any previous working projects folder and navigate to the link showed in the error, that is Projects/(working project name)/packages/Microsoft.Net.Compilers.1.3.2/tools/ and search for Microsoft.CSharp.Core.targets file.

  2. Copy this file and put it in the non-working project tools folder (that is, navigating to the tools folder in the non-working project as shown above)

  3. Now close your project (if it was open) and reopen it.

It should be working now.

Also, to make sure everything is working properly in your now open Visual Studio Project, Go to Tools > NuGetPackage Manager > Manage NuGet Packages For Solution. Here, you might find an error that says, CodeAnalysis.dll is being used by another application.

Again, go to the tools folder, find the specified file and delete it. Come back to Manage NuGet Packages For Solution. You will find a link that will ask you to Reload, click it and everything gets re-installed.

Your project should be working properly now.

How to change FontSize By JavaScript?

try this:

var span = document.getElementById("span");
span.style.fontSize = "25px";
span.innerHTML = "String";

how to set length of an column in hibernate with maximum length

You can use Length annotation for a column. By using it you can maximize or minimize column length. Length annotation only be used for Strings.

@Column(name = "NAME", nullable = false, length = 50)  
@Length(max = 50)
public String getName() {
    return this.name;
}

Format datetime to YYYY-MM-DD HH:mm:ss in moment.js

Use different format or pattern to get the information from the date

_x000D_
_x000D_
var myDate = new Date("2015-06-17 14:24:36");_x000D_
console.log(moment(myDate).format("YYYY-MM-DD HH:mm:ss"));_x000D_
console.log("Date: "+moment(myDate).format("YYYY-MM-DD"));_x000D_
console.log("Year: "+moment(myDate).format("YYYY"));_x000D_
console.log("Month: "+moment(myDate).format("MM"));_x000D_
console.log("Month: "+moment(myDate).format("MMMM"));_x000D_
console.log("Day: "+moment(myDate).format("DD"));_x000D_
console.log("Day: "+moment(myDate).format("dddd"));_x000D_
console.log("Time: "+moment(myDate).format("HH:mm")); // Time in24 hour format_x000D_
console.log("Time: "+moment(myDate).format("hh:mm A"));
_x000D_
<script src="https://momentjs.com/downloads/moment.js"></script>
_x000D_
_x000D_
_x000D_

For more info: https://momentjs.com/docs/#/parsing/string-format/

Run jar file with command line arguments

For the question

How can i run a jar file in command prompt but with arguments

.

To pass arguments to the jar file at the time of execution

java -jar myjar.jar arg1 arg2

In the main() method of "Main-Class" [mentioned in the manifest.mft file]of your JAR file. you can retrieve them like this:

String arg1 = args[0];
String arg2 = args[1];

MySQL JDBC Driver 5.1.33 - Time Zone Issue

The above program will generate that time zone error.

After your database name you have to add this: ?useTimezone=true&serverTimezone=UTC. Once you have done your code will work fine.

Best of luck :)

How to check if object has any properties in JavaScript?

You can loop over the properties of your object as follows:

for(var prop in ad) {
    if (ad.hasOwnProperty(prop)) {
        // handle prop as required
    }
}

It is important to use the hasOwnProperty() method, to determine whether the object has the specified property as a direct property, and not inherited from the object's prototype chain.

Edit

From the comments: You can put that code in a function, and make it return false as soon as it reaches the part where there is the comment

How can you find the height of text on an HTML canvas?

As JJ Stiff suggests, you can add your text to a span and then measure the offsetHeight of the span.

var d = document.createElement("span");
d.font = "20px arial";
d.textContent = "Hello world!";
document.body.appendChild(d);
var emHeight = d.offsetHeight;
document.body.removeChild(d);

As shown on HTML5Rocks

How do I extract the contents of an rpm?

The powerful text-based file manager mc (Midnight Commander, vaguely reminding the Norton Commander of old DOS times) has the built-in capability of inspecting and unpacking .rpm and .rpms files, just "open" the .rpm(s) file within mc and select CONTENTS.cpio: for an rpm you get access to the install tree, for an rpms you get access to the .spec file and all the source packages.

How to sort in-place using the merge sort algorithm?

It really isn't easy or efficient, and I suggest you don't do it unless you really have to (and you probably don't have to unless this is homework since the applications of inplace merging are mostly theoretical). Can't you use quicksort instead? Quicksort will be faster anyway with a few simpler optimizations and its extra memory is O(log N).

Anyway, if you must do it then you must. Here's what I found: one and two. I'm not familiar with the inplace merge sort, but it seems like the basic idea is to use rotations to facilitate merging two arrays without using extra memory.

Note that this is slower even than the classic merge sort that's not inplace.

How to format time since xxx e.g. “4 minutes ago” similar to Stack Exchange sites

 I achieve this by following method

   timeAgo = (date) => {
            var ms = (new Date()).getTime() - date.getTime();
            var seconds = Math.floor(ms / 1000);
            var minutes = Math.floor(seconds / 60);
        var hours = Math.floor(minutes / 60);
        var days = Math.floor(hours / 24);
        var months = Math.floor(days / 30);
        var years = Math.floor(months / 12);
    
        if (ms === 0) {
            return 'Just now';
        } if (seconds < 60) {
            return seconds + ' seconds Ago';
        } if (minutes < 60) {
            return minutes + ' minutes Ago';
        } if (hours < 24) {
            return hours + ' hours Ago';
        } if (days < 30) {
            return days + ' days Ago';
        } if (months < 12) {
            return months + ' months Ago';
        } else {
            return years + ' years Ago';
        }
    
    }
    
        console.log(timeAgo(new Date()));
        console.log(timeAgo(new Date('Jun 27 2020 10:12:19')));
        console.log(timeAgo(new Date('Jun 27 2020 00:12:19')));
        console.log(timeAgo(new Date('May 28 2020 13:12:19')));
        console.log(timeAgo(new Date('May 28 2017 13:12:19')));

How can I make my flexbox layout take 100% vertical space?

You should set height of html, body, .wrapper to 100% (in order to inherit full height) and then just set a flex value greater than 1 to .row3 and not on the others.

_x000D_
_x000D_
.wrapper, html, body {
    height: 100%;
    margin: 0;
}
.wrapper {
    display: flex;
    flex-direction: column;
}
#row1 {
    background-color: red;
}
#row2 {
    background-color: blue;
}
#row3 {
    background-color: green;
    flex:2;
    display: flex;
}
#col1 {
    background-color: yellow;
    flex: 0 0 240px;
    min-height: 100%;/* chrome needed it a question time , not anymore */
}
#col2 {
    background-color: orange;
    flex: 1 1;
    min-height: 100%;/* chrome needed it a question time , not anymore */
}
#col3 {
    background-color: purple;
    flex: 0 0 240px;
    min-height: 100%;/* chrome needed it a question time , not anymore */
}
_x000D_
<div class="wrapper">
    <div id="row1">this is the header</div>
    <div id="row2">this is the second line</div>
    <div id="row3">
        <div id="col1">col1</div>
        <div id="col2">col2</div>
        <div id="col3">col3</div>
    </div>
</div>
_x000D_
_x000D_
_x000D_

DEMO

What is REST? Slightly confused

REST is not a specific web service but a design concept (architecture) for managing state information. The seminal paper on this was Roy Thomas Fielding's dissertation (2000), "Architectural Styles and the Design of Network-based Software Architectures" (available online from the University of California, Irvine).

First read Ryan Tomayko's post How I explained REST to my wife; it's a great starting point. Then read Fielding's actual dissertation. It's not that advanced, nor is it long (six chapters, 180 pages)! (I know you kids in school like it short).

EDIT: I feel it's pointless to try to explain REST. It has so many concepts like scalability, visibility (stateless) etc. that the reader needs to grasp, and the best source for understanding those are the actual dissertation. It's much more than POST/GET etc.

How do you get the process ID of a program in Unix or Linux using Python?

This is a simplified variation of Fernando's answer. This is for Linux and either Python 2 or 3. No external library is needed, and no external process is run.

import glob

def get_command_pid(command):
    for path in glob.glob('/proc/*/comm'):
        if open(path).read().rstrip() == command:
            return path.split('/')[2]

Only the first matching process found will be returned, which works well for some purposes. To get the PIDs of multiple matching processes, you could just replace the return with yield, and then get a list with pids = list(get_command_pid(command)).

Alternatively, as a single expression:

For one process:

next(path.split('/')[2] for path in glob.glob('/proc/*/comm') if open(path).read().rstrip() == command)

For multiple processes:

[path.split('/')[2] for path in glob.glob('/proc/*/comm') if open(path).read().rstrip() == command]

Git merge without auto commit

You're misunderstanding the meaning of the merge here.

The --no-commit prevents the MERGE COMMIT from occuring, and that only happens when you merge two divergent branch histories; in your example that's not the case since Git indicates that it was a "fast-forward" merge and then Git only applies the commits already present on the branch sequentially.

Get names of all keys in the collection

Here is the sample worked in Python: This sample returns the results inline.

from pymongo import MongoClient
from bson.code import Code

mapper = Code("""
    function() {
                  for (var key in this) { emit(key, null); }
               }
""")
reducer = Code("""
    function(key, stuff) { return null; }
""")

distinctThingFields = db.things.map_reduce(mapper, reducer
    , out = {'inline' : 1}
    , full_response = True)
## do something with distinctThingFields['results']

Set maxlength in Html Textarea

Before HTML5 it's only possible to check this with JavaScript or by a server-side verification (better, because JavaScript obviously only works with JavaScript enabled...). There is no native max-length attribute for textareas.

Since HTML5 it's a valid attribut, so defining your doctype as HTML5 may help. I don't know if all browsers support this attribute, though:

<!DOCTYPE html>

Python how to exit main function

You can't return because you're not in a function. You can exit though.

import sys
sys.exit(0)

0 (the default) means success, non-zero means failure.

Get query from java.sql.PreparedStatement

I would assume it's possible to place a proxy between the DB and your app then observe the communication. I'm not familiar with what software you would use to do this.

Longer object length is not a multiple of shorter object length?

Yes, this is something that you should worry about. Check the length of your objects with nrow(). R can auto-replicate objects so that they're the same length if they differ, which means you might be performing operations on mismatched data.

In this case you have an obvious flaw in that your subtracting aggregated data from raw data. These will definitely be of different lengths. I suggest that you merge them as time series (using the dates), then locf(), then do your subtraction. Otherwise merge them by truncating the original dates to the same interval as the aggregated series. Just be very careful that you don't drop observations.

Lastly, as some general advice as you get started: look at the result of your computations to see if they make sense. You might even pull them into a spreadsheet and replicate the results.

find without recursion

If you look for POSIX compliant solution:

cd DirsRoot && find . -type f -print -o -name . -o -prune

-maxdepth is not POSIX compliant option.

Get human readable version of file size?

Here is an option using while:

def number_format(n):
   n2, n3 = n, 0
   while n2 >= 1e3:
      n2 /= 1e3
      n3 += 1
   return '%.3f' % n2 + ('', ' k', ' M', ' G')[n3]

s = number_format(9012345678)
print(s == '9.012 G')

https://docs.python.org/reference/compound_stmts.html#while

SQL Server : login success but "The database [dbName] is not accessible. (ObjectExplorer)"

My issue got resolved by restarting the MS SQL server service, simple.

jQuery trigger event when click outside the element

I do not think document fires the click event. Try using the body element to capture the click event. Might need to check on that...

jQuery make global variable

Your code looks fine except the possibility that if the variable declaration is inside a dom read handler then it will not be a global variable... it will be a closure variable

jQuery(function(){
    //here it is a closure variable
    var a_href;
    $('sth a').on('click', function(e){
        a_href = $(this).attr('href');

          console.log(a_href);  
         //output is "home"

        e.preventDefault();
    }
})

To make the variable global, one solution is to declare the variable in global scope

var a_href;
jQuery(function(){
    $('sth a').on('click', function(e){
        a_href = $(this).attr('href');

          console.log(a_href);  
         //output is "home"

        e.preventDefault();
    }
})

another is to set the variable as a property of the window object

window.a_href = $(this).attr('href')

Why console printing undefined

You are getting the output as undefined because even though the variable is declared, you have not initialized it with a value, the value of the variable is set only after the a element is clicked till that time the variable will have the value undefined. If you are not declaring the variable it will throw a ReferenceError

How to create file object from URL object (image)

You can convert the URL to a String and use it to create a new File. e.g.

URL url = new URL("http://google.com/pathtoaimage.jpg");
File f = new File(url.getFile());

How to deal with INSTALL_PARSE_FAILED_INCONSISTENT_CERTIFICATES without uninstall?

I got this error even after uninstalling the original APK, which was mystifying. Finally I realized that I had set up multiple users on my Nexus 7 for testing and that the app was still installed for one of the other users. Once I uninstalled it for all users the error went away.

PHPMailer AddAddress()

foreach ($all_address as $aa) {
    $mail->AddAddress($aa); 
}

jQuery Get Selected Option From Dropdown

I had the same issue and I figured out why it was not working on my case
The html page was divided into different html fragments and I found that I have another input field that carries the same Id of the select, which caused the val() to be always empty
I hope this saves the day for anyone who have similar issue.

Is there an easy way to convert jquery code to javascript?

I just found this quite impressive tutorial about jquery to javascript conversion from Jeffrey Way on Jan 19th 2012 *Copyright © 2014 Envato* :

http://net.tutsplus.com/tutorials/javascript-ajax/from-jquery-to-javascript-a-reference/

Whether we like it or not, more and more developers are being introduced to the world of JavaScript through jQuery first. In many ways, these newcomers are the lucky ones. They have access to a plethora of new JavaScript APIs, which make the process of DOM traversal (something that many folks depend on jQuery for) considerably easier. Unfortunately, they don’t know about these APIs!

In this article, we’ll take a variety of common jQuery tasks, and convert them to both modern and legacy JavaScript.

I proposed it in a comment to OP, and after his suggestion, i publish it has an answer for everyone to refer to.

Also, Jeffrey Way mentioned about his inspiration witch seems to be a good primer for understanding : http://sharedfil.es/js-48hIfQE4XK.html

Has a teaser, this document comparison of jQuery to javascript :

$(document).ready(function() {
  // code…
});

document.addEventListener("DOMContentLoaded", function() {
  // code…
});

$("a").click(function() {
  // code…
})

[].forEach.call(document.querySelectorAll("a"), function(el) {
  el.addEventListener("click", function() {
    // code…
  });
});

You should take a look.

Change the Bootstrap Modal effect


_x000D_
_x000D_
.custom-modal-header_x000D_
{_x000D_
    display: block;_x000D_
}_x000D_
.custom-modal .modal-content_x000D_
{_x000D_
    width:500px;_x000D_
    border: none;_x000D_
}_x000D_
.custom-modal_x000D_
{_x000D_
    display: block !important;_x000D_
}_x000D_
.custom-fade .modal-dialog {_x000D_
    transform: translateY(4%);_x000D_
    opacity: 0;_x000D_
    -webkit-transition: all .2s ease-out;_x000D_
    -o-transition: all .2s ease-out;_x000D_
    transition: all .2s ease-out;_x000D_
    will-change: transform;_x000D_
}_x000D_
.custom-fade.in .modal-dialog  {_x000D_
    opacity: 1;_x000D_
    transform: translateY(0%);_x000D_
}
_x000D_
<div class="modal custom-modal custom-fade" tabindex="-1" role="dialog"_x000D_
     aria-hidden="true">_x000D_
    <div class="modal-dialog modal-lg">_x000D_
        <div class="modal-content">_x000D_
            <div class="modal-header">_x000D_
                <h5 class="modal-title">Title</h5>_x000D_
            </div>_x000D_
            <div class="modal-body">_x000D_
                <p>My cat is dope.</p>_x000D_
            </div>_x000D_
            <div class="modal-footer">_x000D_
                <button type="button" class="btn btn-primary" data-dismiss="modal">Sure (Meow)</button>_x000D_
            </div>_x000D_
        </div>_x000D_
    </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

What are the special dollar sign shell variables?

  • $1, $2, $3, ... are the positional parameters.
  • "$@" is an array-like construct of all positional parameters, {$1, $2, $3 ...}.
  • "$*" is the IFS expansion of all positional parameters, $1 $2 $3 ....
  • $# is the number of positional parameters.
  • $- current options set for the shell.
  • $$ pid of the current shell (not subshell).
  • $_ most recent parameter (or the abs path of the command to start the current shell immediately after startup).
  • $IFS is the (input) field separator.
  • $? is the most recent foreground pipeline exit status.
  • $! is the PID of the most recent background command.
  • $0 is the name of the shell or shell script.

Most of the above can be found under Special Parameters in the Bash Reference Manual. There are all the environment variables set by the shell.

For a comprehensive index, please see the Reference Manual Variable Index.

Calculating time difference between 2 dates in minutes

I think you could use TIMESTAMPDIFF(unit,datetime_expr1,datetime_expr2) something like

select * from MyTab T where
TIMESTAMPDIFF(MINUTE,T.runTime,NOW()) > 20

How can I have linebreaks in my long LaTeX equations?

I think I usually used eqnarray or something. It lets you say

\begin{eqnarray*}
    x &=& blah blah blah \\ 
      & & more blah blah blah \\
      & & even more blah blah
\end{eqnarray*}

and it will be aligned by the & &... As pkaeding mentioned, it's hard to read, but when you've got an equation thats that long, it's gonna be hard to read no matter what... (The * makes it not have an equation number, IIRC)

batch file to check 64bit or 32bit OS

None of the answers here were working in my case (64 bit processor but 32 bit OS), so here's the solution which worked for me:

(set | find "ProgramFiles(x86)" > NUL) && (echo "%ProgramFiles(x86)%" | find "x86") > NUL && set bits=64 || set bits=32

Operation Not Permitted when on root - El Capitan (rootless disabled)

Correct solution is to copy or install to /usr/local/bin not /usr/bin.This is due to System Integrity Protection (SIP). SIP makes /usr/bin read-only but leaves /usr/local as read-write.

SIP should not be disabled as stated in the answer above because it adds another layer of protection against malware gaining root access. Here is a complete explanation of what SIP does and why it is useful.

As suggested in this answer one should not disable SIP (rootless mode) "It is not recommended to disable rootless mode! The best practice is to install custom stuff to "/usr/local" only."

How to read all rows from huge table?

I did it like below. Not the best way i think, but it works :)

    Connection c = DriverManager.getConnection("jdbc:postgresql://....");
    PreparedStatement s = c.prepareStatement("select * from " + tabName + " where id > ? order by id");
    s.setMaxRows(100);
    int lastId = 0;
    for (;;) {
        s.setInt(1, lastId);
        ResultSet rs = s.executeQuery();

        int lastIdBefore = lastId;
        while (rs.next()) {
            lastId = Integer.parseInt(rs.getObject(1).toString());
            // ...
        }

        if (lastIdBefore == lastId) {
            break;
        }
    }

Null pointer Exception on .setOnClickListener

I too got similar error when i misplaced the code

text=(TextView)findViewById(R.id.text);// this line has to be below setcontentview
setContentView(R.layout.activity_my_otype);
//this is the correct place
text.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            }
    });

I got it working on placing the code in right order as shown below

setContentView(R.layout.activity_my_otype);
text=(TextView)findViewById(R.id.text);
 text.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            }
    });

SQL Server IIF vs CASE

IIF is the same as CASE WHEN <Condition> THEN <true part> ELSE <false part> END. The query plan will be the same. It is, perhaps, "syntactical sugar" as initially implemented.

CASE is portable across all SQL platforms whereas IIF is SQL SERVER 2012+ specific.

Unsetting array values in a foreach loop

Try that:

foreach ($images[1] as $key => &$image) {
    if (yourConditionGoesHere) {
        unset($images[1][$key])
    }
}
unset($image); // detach reference after loop  

Normally, foreach operates on a copy of your array so any changes you make, are made to that copy and don't affect the actual array.

So you need to unset the values via $images[$key];

The reference on &$image prevents the loop from creating a copy of the array which would waste memory.

Get loop count inside a Python FOR loop

I know rather old question but....came across looking other thing so I give my shot:

[each*2 for each in [1,2,3,4,5] if each % 10 == 0])

Can Android Studio be used to run standard Java projects?

EDIT: many moon after this question was asked, yes, now apparently you can.

No, but it's based on Intellij IDEA.

The community version of that is free for download but it doesn't support most things requiring an external database or application server. The line for Java is pretty much that JavaSE code can happily use Community.

If you want that (or are using JavaEE) then you either need the Ultimate version, which isn't free, or the EAP of the next version which is usually good for a month until they release another.

Basically it works like this

Android Studio is just Android the Android Stuff from IDEA 13 Community...

...which will be free, and is anything from IDEA 13 Ultimate...

...that doesn't require a database or app server.

http://www.jetbrains.com/idea/

IDEA 12 Community doesn't have the ability to import the gradilized project and it won't, so while you can do Android development in it now (I do), don't expect it to have the same features as Android Studio. There's a lot of good new Android stuff in it, that's going into 13.

DataAnnotations validation (Regular Expression) in asp.net mvc 4 - razor view

UPDATE 9 July 2012 - Looks like this is fixed in RTM.

  1. We already imply ^ and $ so you don't need to add them. (It doesn't appear to be a problem to include them, but you don't need them)
  2. This appears to be a bug in ASP.NET MVC 4/Preview/Beta. I've opened a bug

View source shows the following:

data-val-regex-pattern="([a-zA-Z0-9 .&amp;&#39;-]+)"                  <-- MVC 3
data-val-regex-pattern="([a-zA-Z0-9&#32;.&amp;amp;&amp;#39;-]+)"      <-- MVC 4/Beta

It looks like we're double encoding.

Remove all special characters, punctuation and spaces from string

Python 2.*

I think just filter(str.isalnum, string) works

In [20]: filter(str.isalnum, 'string with special chars like !,#$% etcs.')
Out[20]: 'stringwithspecialcharslikeetcs'

Python 3.*

In Python3, filter( ) function would return an itertable object (instead of string unlike in above). One has to join back to get a string from itertable:

''.join(filter(str.isalnum, string)) 

or to pass list in join use (not sure but can be fast a bit)

''.join([*filter(str.isalnum, string)])

note: unpacking in [*args] valid from Python >= 3.5

What's a good (free) visual merge tool for Git? (on windows)

I've been using P4Merge, it's free and cross platform.

P4Merge

Best practice to look up Java Enum

Probably you can implement generic static lookup method.

Like so

public class LookupUtil {
   public static <E extends Enum<E>> E lookup(Class<E> e, String id) {   
      try {          
         E result = Enum.valueOf(e, id);
      } catch (IllegalArgumentException e) {
         // log error or something here

         throw new RuntimeException(
           "Invalid value for enum " + e.getSimpleName() + ": " + id);
      }

      return result;
   }
}

Then you can

public enum MyEnum {
   static public MyEnum lookup(String id) {
       return LookupUtil.lookup(MyEnum.class, id);
   }
}

or call explicitly utility class lookup method.

Get environment value in controller

In config/app.php file make a instance of env variable like 'name' => env('APP_NAME', 'Laravel') & In your controller call it like config('app.name')

Run following commands php artisan config:cache php artisan cache:clear if it is not working.

SQL Server: convert ((int)year,(int)month,(int)day) to Datetime

You could convert your values into a 'Decimal' datetime and convert it then to a real datetime column:

select cast(rtrim(year *10000+ month *100+ day) as datetime) as Date from DateTable

See here as well for more info.

Java enum with multiple value types

First, the enum methods shouldn't be in all caps. They are methods just like other methods, with the same naming convention.

Second, what you are doing is not the best possible way to set up your enum. Instead of using an array of values for the values, you should use separate variables for each value. You can then implement the constructor like you would any other class.

Here's how you should do it with all the suggestions above:

public enum States {
    ...
    MASSACHUSETTS("Massachusetts",  "MA",   true),
    MICHIGAN     ("Michigan",       "MI",   false),
    ...; // all 50 of those

    private final String full;
    private final String abbr;
    private final boolean originalColony;

    private States(String full, String abbr, boolean originalColony) {
        this.full = full;
        this.abbr = abbr;
        this.originalColony = originalColony;
    }

    public String getFullName() {
        return full;
    }

    public String getAbbreviatedName() {
        return abbr;
    }

    public boolean isOriginalColony(){
        return originalColony;
    }
}

What's the fastest way of checking if a point is inside a polygon in python

If speed is what you need and extra dependencies are not a problem, you maybe find numba quite useful (now it is pretty easy to install, on any platform). The classic ray_tracing approach you proposed can be easily ported to numba by using numba @jit decorator and casting the polygon to a numpy array. The code should look like:

@jit(nopython=True)
def ray_tracing(x,y,poly):
    n = len(poly)
    inside = False
    p2x = 0.0
    p2y = 0.0
    xints = 0.0
    p1x,p1y = poly[0]
    for i in range(n+1):
        p2x,p2y = poly[i % n]
        if y > min(p1y,p2y):
            if y <= max(p1y,p2y):
                if x <= max(p1x,p2x):
                    if p1y != p2y:
                        xints = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                    if p1x == p2x or x <= xints:
                        inside = not inside
        p1x,p1y = p2x,p2y

    return inside

The first execution will take a little longer than any subsequent call:

%%time
polygon=np.array(polygon)
inside1 = [numba_ray_tracing_method(point[0], point[1], polygon) for 
point in points]

CPU times: user 129 ms, sys: 4.08 ms, total: 133 ms
Wall time: 132 ms

Which, after compilation will decrease to:

CPU times: user 18.7 ms, sys: 320 µs, total: 19.1 ms
Wall time: 18.4 ms

If you need speed at the first call of the function you can then pre-compile the code in a module using pycc. Store the function in a src.py like:

from numba import jit
from numba.pycc import CC
cc = CC('nbspatial')


@cc.export('ray_tracing',  'b1(f8, f8, f8[:,:])')
@jit(nopython=True)
def ray_tracing(x,y,poly):
    n = len(poly)
    inside = False
    p2x = 0.0
    p2y = 0.0
    xints = 0.0
    p1x,p1y = poly[0]
    for i in range(n+1):
        p2x,p2y = poly[i % n]
        if y > min(p1y,p2y):
            if y <= max(p1y,p2y):
                if x <= max(p1x,p2x):
                    if p1y != p2y:
                        xints = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                    if p1x == p2x or x <= xints:
                        inside = not inside
        p1x,p1y = p2x,p2y

    return inside


if __name__ == "__main__":
    cc.compile()

Build it with python src.py and run:

import nbspatial

import numpy as np
lenpoly = 100
polygon = [[np.sin(x)+0.5,np.cos(x)+0.5] for x in 
np.linspace(0,2*np.pi,lenpoly)[:-1]]

# random points set of points to test 
N = 10000
# making a list instead of a generator to help debug
points = zip(np.random.random(N),np.random.random(N))

polygon = np.array(polygon)

%%time
result = [nbspatial.ray_tracing(point[0], point[1], polygon) for point in points]

CPU times: user 20.7 ms, sys: 64 µs, total: 20.8 ms
Wall time: 19.9 ms

In the numba code I used: 'b1(f8, f8, f8[:,:])'

In order to compile with nopython=True, each var needs to be declared before the for loop.

In the prebuild src code the line:

@cc.export('ray_tracing' , 'b1(f8, f8, f8[:,:])')

Is used to declare the function name and its I/O var types, a boolean output b1 and two floats f8 and a two-dimensional array of floats f8[:,:] as input.

Edit Jan/4/2021

For my use case, I need to check if multiple points are inside a single polygon - In such a context, it is useful to take advantage of numba parallel capabilities to loop over a series of points. The example above can be changed to:

from numba import jit, njit
import numba
import numpy as np 

@jit(nopython=True)
def pointinpolygon(x,y,poly):
    n = len(poly)
    inside = False
    p2x = 0.0
    p2y = 0.0
    xints = 0.0
    p1x,p1y = poly[0]
    for i in numba.prange(n+1):
        p2x,p2y = poly[i % n]
        if y > min(p1y,p2y):
            if y <= max(p1y,p2y):
                if x <= max(p1x,p2x):
                    if p1y != p2y:
                        xints = (y-p1y)*(p2x-p1x)/(p2y-p1y)+p1x
                    if p1x == p2x or x <= xints:
                        inside = not inside
        p1x,p1y = p2x,p2y

    return inside


@njit(parallel=True)
def parallelpointinpolygon(points, polygon):
    D = np.empty(len(points), dtype=numba.boolean) 
    for i in numba.prange(0, len(D)):
        D[i] = pointinpolygon(points[i,0], points[i,1], polygon)
    return D    

Note: pre-compiling the above code will not enable the parallel capabilities of numba (parallel CPU target is not supported by pycc/AOT compilation) see: https://github.com/numba/numba/issues/3336

Test:


import numpy as np
lenpoly = 100
polygon = [[np.sin(x)+0.5,np.cos(x)+0.5] for x in np.linspace(0,2*np.pi,lenpoly)[:-1]]
polygon = np.array(polygon)
N = 10000
points = np.random.uniform(-1.5, 1.5, size=(N, 2))

For N=10000 on a 72 core machine, returns:

%%timeit
parallelpointinpolygon(points, polygon)
# 480 µs ± 8.19 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)

Edit 17 Feb '21:

  • fixing loop to start from 0 instead of 1 (thanks @mehdi):

for i in numba.prange(0, len(D))

Edit 20 Feb '21:

Follow-up on the comparison made by @mehdi, I am adding a GPU-based method below. It uses the point_in_polygon method, from the cuspatial library:

    import numpy as np
    import cudf
    import cuspatial

    N = 100000002
    lenpoly = 1000
    polygon = [[np.sin(x)+0.5,np.cos(x)+0.5] for x in 
    np.linspace(0,2*np.pi,lenpoly)]
    polygon = np.array(polygon)
    points = np.random.uniform(-1.5, 1.5, size=(N, 2))


    x_pnt = points[:,0]
    y_pnt = points[:,1]
    x_poly =polygon[:,0]
    y_poly = polygon[:,1]
    result = cuspatial.point_in_polygon(
        x_pnt,
        y_pnt,
        cudf.Series([0], index=['geom']),
        cudf.Series([0], name='r_pos', dtype='int32'), 
        x_poly, 
        y_poly,
    )

Following @Mehdi comparison. For N=100000002 and lenpoly=1000 - I got the following results:

 time_parallelpointinpolygon:         161.54760098457336 
 time_mpltPath:                       307.1664695739746 
 time_ray_tracing_numpy_numba:        353.07356882095337 
 time_is_inside_sm_parallel:          37.45389246940613 
 time_is_inside_postgis_parallel:     127.13793849945068 
 time_is_inside_rapids:               4.246025562286377

point in poligon methods comparison, #poins: 10e07

hardware specs:

  • CPU Intel xeon E1240
  • GPU Nvidia GTX 1070

Notes:

  • The cuspatial.point_in_poligon method, is quite robust and powerful, it offers the ability to work with multiple and complex polygons (I guess at the expense of performance)

  • The numba methods can also be 'ported' on the GPU - it will be interesting to see a comparison which includes a porting to cuda of fastest method mentioned by @Mehdi (is_inside_sm).

Node Version Manager install - nvm command not found

source ~/.nvm/nvm.sh Add this line to ~/.bashrc, ~/.profile, or ~/.zshrc

How do I get column datatype in Oracle with PL-SQL with low privileges?

Quick and dirty way (e.g. to see how data is stored in oracle)

SQL> select dump(dummy) dump_dummy, dummy
     , dump(10) dump_ten
from dual

DUMP_DUMMY       DUMMY DUMP_TEN            
---------------- ----- --------------------
Typ=1 Len=1: 88  X     Typ=2 Len=2: 193,11 
1 row selected.

will show that dummy column in table sys.dual has typ=1 (varchar2), while 10 is Typ=2 (number).

How to completely remove node.js from Windows

Scenario: Removing NodeJS when Windows has no Program Entry for your Node installation

I ran into a problem where my version of NodeJS (0.10.26) could NOT be uninstalled nor removed, because Programs & Features in Windows 7 (aka Add/Remove Programs) had no record of my having installed NodeJS... so there was no option to remove it short of manually deleting registry keys and files.

Command to verify your NodeJS version: node --version

I attempted to install the newest recommended version of NodeJS, but it failed at the end of the installation process and rolled back. Multiple versions of NodeJS also failed, and the installer likewise rolled them back as well. I could not upgrade NodeJS from the command line as I did not have SUDO installed.

SOLUTION: After spending several hours troubleshooting the problem, including upgrading NPM, I decided to reinstall the EXACT version of NodeJS on my system, over the top of the existing installation.

That solution worked, and it reinstalled NodeJS without any errors. Better yet, it also added an official entry in Add/Remove Programs dialogue.

Now that Windows was aware of the forgotten NodeJS installation, I was able to uninstall my existing version of NodeJS completely. I then successfully installed the newest recommended release of NodeJS for the Windows platform (version 4.4.5 as of this writing) without a roll-back initiating.

It took me a while to reach sucess, so I am posting this in case it helps anyone else with a similar issue.

How to get calendar Quarter from a date in TSQL

Try the following:

CONCAT(datepart(yyyy,DATE),'-', DATEPART(qq,DATE))

It returns:

yyyy-q

Example: 2017-3 for 2017-07-11

Builder Pattern in Effective Java

This mean that you cant create enclose type. This mean that first you have to cerate a instance of "parent" class and then from this instance you can create nested class instances.

NutritionalFacts n = new NutritionalFacts()

Builder b = new n.Builder(10).carbo(23).fat(1).build();

Nested Classes

How do I use su to execute the rest of the bash script as that user?

Here is yet another approach, which was more convenient in my case (I just wanted to drop root privileges and do the rest of my script from restricted user): you can make the script restart itself from correct user. Let's suppose it is run as root initially. Then it will look like this:

#!/bin/bash
if [ $UID -eq 0 ]; then
  user=$1
  dir=$2
  shift 2     # if you need some other parameters
  cd "$dir"
  exec su "$user" "$0" -- "$@"
  # nothing will be executed beyond that line,
  # because exec replaces running process with the new one
fi

echo "This will be run from user $UID"
...

Model backing a DB Context has changed; Consider Code First Migrations

Entity Framework detects something about the model has changed, you need to do something to the database to get this work. Solution: 1. enable-migrations 2. update-database

How can I write a heredoc to a file in Bash script?

To build on @Livven's answer, here are some useful combinations.

  1. variable substitution, leading tab retained, overwrite file, echo to stdout

    tee /path/to/file <<EOF
    ${variable}
    EOF
    
  2. no variable substitution, leading tab retained, overwrite file, echo to stdout

    tee /path/to/file <<'EOF'
    ${variable}
    EOF
    
  3. variable substitution, leading tab removed, overwrite file, echo to stdout

    tee /path/to/file <<-EOF
        ${variable}
    EOF
    
  4. variable substitution, leading tab retained, append to file, echo to stdout

    tee -a /path/to/file <<EOF
    ${variable}
    EOF
    
  5. variable substitution, leading tab retained, overwrite file, no echo to stdout

    tee /path/to/file <<EOF >/dev/null
    ${variable}
    EOF
    
  6. the above can be combined with sudo as well

    sudo -u USER tee /path/to/file <<EOF
    ${variable}
    EOF
    

Custom Input[type="submit"] style not working with jquerymobile button

jQuery Mobile >= 1.4

Create a custom class, e.g. .custom-btn. Note that to override jQM styles without using !important, CSS hierarchy should be respected. .ui-btn.custom-class or .ui-input-btn.custom-class.

.ui-input-btn.custom-btn {
   border:1px solid red;
   text-decoration:none;
   font-family:helvetica;
   color:red;
   background:url(img.png) repeat-x;
}

Add a data-wrapper-class to input. The custom class will be added to input wrapping div.

<input type="button" data-wrapper-class="custom-btn">

Demo


jQuery Mobile <= 1.3

Input button is wrapped by a DIV with class ui-btn. You need to select that div and the input[type="submit"]. Using !important is essential to override Jquery Mobile styles.

Demo

div.ui-btn, input[type="submit"] {
 border:1px solid red !important;
 text-decoration:none !important;
 font-family:helvetica !important;
 color:red !important;
 background:url(../images/btn_hover.png) repeat-x !important;
}

Read HttpContent in WebApi controller

You can keep your CONTACT parameter with the following approach:

using (var stream = new MemoryStream())
{
    var context = (HttpContextBase)Request.Properties["MS_HttpContext"];
    context.Request.InputStream.Seek(0, SeekOrigin.Begin);
    context.Request.InputStream.CopyTo(stream);
    string requestBody = Encoding.UTF8.GetString(stream.ToArray());
}

Returned for me the json representation of my parameter object, so I could use it for exception handling and logging.

Found as accepted answer here

When to use references vs. pointers

From C++ FAQ Lite -

Use references when you can, and pointers when you have to.

References are usually preferred over pointers whenever you don't need "reseating". This usually means that references are most useful in a class's public interface. References typically appear on the skin of an object, and pointers on the inside.

The exception to the above is where a function's parameter or return value needs a "sentinel" reference — a reference that does not refer to an object. This is usually best done by returning/taking a pointer, and giving the NULL pointer this special significance (references must always alias objects, not a dereferenced NULL pointer).

Note: Old line C programmers sometimes don't like references since they provide reference semantics that isn't explicit in the caller's code. After some C++ experience, however, one quickly realizes this is a form of information hiding, which is an asset rather than a liability. E.g., programmers should write code in the language of the problem rather than the language of the machine.

How to make a redirection on page load in JSF 1.x

Set the GET query parameters as managed properties in faces-config.xml so that you don't need to gather them manually:

<managed-bean>
    <managed-bean-name>forward</managed-bean-name>
    <managed-bean-class>com.example.ForwardBean</managed-bean-class>
    <managed-bean-scope>request</managed-bean-scope>
    <managed-property>
        <property-name>action</property-name>
        <value>#{param.action}</value>
    </managed-property>
    <managed-property>
        <property-name>actionParam</property-name>
        <value>#{param.actionParam}</value>
    </managed-property>
</managed-bean>

This way the request forward.jsf?action=outcome1&actionParam=123 will let JSF set the action and actionParam parameters as action and actionParam properties of the ForwardBean.

Create a small view forward.xhtml (so small that it fits in default response buffer (often 2KB) so that it can be resetted by the navigationhandler, otherwise you've to increase the response buffer in the servletcontainer's configuration), which invokes a bean method on beforePhase of the f:view:

<!DOCTYPE html>
<html xmlns:f="http://java.sun.com/jsf/core">
    <f:view beforePhase="#{forward.navigate}" />
</html>

The ForwardBean can look like this:

public class ForwardBean {
    private String action;
    private String actionParam;

    public void navigate(PhaseEvent event) {
        FacesContext facesContext = FacesContext.getCurrentInstance();
        String outcome = action; // Do your thing?
        facesContext.getApplication().getNavigationHandler().handleNavigation(facesContext, null, outcome);
    }

    // Add/generate the usual boilerplate.
}

The navigation-rule speaks for itself (note the <redirect /> entries which would do ExternalContext#redirect() instead of ExternalContext#dispatch() under the covers):

<navigation-rule>
    <navigation-case>
        <from-outcome>outcome1</from-outcome>
        <to-view-id>/outcome1.xhtml</to-view-id>
        <redirect />
    </navigation-case>
    <navigation-case>
        <from-outcome>outcome2</from-outcome>
        <to-view-id>/outcome2.xhtml</to-view-id>
        <redirect />
    </navigation-case>
</navigation-rule>

An alternative is to use forward.xhtml as

<!DOCTYPE html>
<html>#{forward}</html>

and update the navigate() method to be invoked on @PostConstruct (which will be invoked after bean's construction and all managed property setting):

@PostConstruct
public void navigate() {
    // ...
}    

It has the same effect, however the view side is not really self-documenting. All it basically does is printing ForwardBean#toString() (and hereby implicitly constructing the bean if not present yet).


Note for the JSF2 users, there is a cleaner way of passing parameters with <f:viewParam> and more robust way of handling the redirect/navigation by <f:event type="preRenderView">. See also among others:

What is the size of a boolean variable in Java?

It's virtual machine dependent.

How to convert/parse from String to char in java?

If you want to parse a String to a char, whereas the String object represent more than one character, you just simply use the following expression: char c = (char) Integer.parseInt(s). Where s equals the String you want to parse. Most people forget that char's represent a 16-bit number, and thus can be a part of any numerical expression :)

What are the RGB codes for the Conditional Formatting 'Styles' in Excel?

For anyone who stumbles across this in the future, this is how you do it:

xl.Range("A1:A1").Style := "Bad"
xl.Range("A1:A1").Style := "Good"
xl.Range("A1:A1").Style := "Neutral"

An easy way to check on things like this is to open excel and record a macro. In this case I recorded a macro where I just formatted the cell to "Bad". Once you've recorded the macro, just go in and edit it and it will essentially give you the code. It will require a little translation on your part, but here is what the macro looks like when I edit it:

 Selection.Style = "Bad"

As you can see, it's pretty easy to make the jump to AHK from what excel provides.

What does "subject" mean in certificate?

Subject is the certificate's common name and is a critical property for the certificate in a lot of cases if it's a server certificate and clients are looking for a positive identification.

As an example on an SSL certificate for a web site the subject would be the domain name of the web site.

How can I stream webcam video with C#?

You could just use VideoLAN. VideoLAN will work as a server (or you can wrap your own C# application around it for more control). There are also .NET wrappers for the viewer that you can use and thus embed in your C# client.

What's the difference between the atomic and nonatomic attributes?

Atomic properties :- When a variable assigned with atomic property that means it has only one thread access and it will be thread safe and will be good in performance perspective, will have default behaviour.

Non Atomic Properties :- When a variable assigned with atomic property that means it has multi thread access and it will not be thread safe and will be slow in performance perspective, will have default behaviour and when two different threads want to access variable at same time it will give unexpected results.

change <audio> src with javascript

Try this:

Replace:

audio.load();

with:

audio.play();

Can I have an onclick effect in CSS?

TylerH made a really good answer, I just had to give that last button a visual update.

_x000D_
_x000D_
.btn {
    border-radius: 5px;
    padding: 10px 30px;
    box-shadow: 1px 1px 1px #000;
    background-image: linear-gradient(to bottom, #eee, #ddd);
}

.btn:hover {
    background-image: linear-gradient(to top, #adf, #8bf);
}

.btn:active {
    margin: 1px 1px 0;
    box-shadow: -1px -1px 1px #000;
}

#btnControl {
    display: block;
    visibility: hidden;
}
_x000D_
<input type="checkbox" id="btnControl"/>
<label class="btn" for="btnControl">Click me!</label>
_x000D_
_x000D_
_x000D_

Maven : error in opening zip file when running maven

I had the same problem but previous solutions not work for me. The only solution works for me is the following URL.

https://enlightensoft.wordpress.com/2013/01/15/maven-error-reading-error-in-opening-zip-file/

[EDIT]

Here I explain more about it

Suppose you got an error like below

[ERROR] error: error reading C:\Users\user\.m2\repository\org\jdom\jdom\1.1\jdom-1.1.jar; error in opening zip file

Then you have to follow these steps.

  1. First, delete the existing jar C:\Users\user\.m2\repository\org\jdom\jdom\1.1\jdom-1.1.jar
  2. Then you have to manually download relevant jar from Maven central repository. You can download from this link here
  3. After that, you have to copy that downloaded jar into the previous directory.C:\Users\user\.m2\repository\org\jdom\jdom\1.1\

Then you can build your project using mvn clean install

hope this will help somebody.

Regex to validate password strength

You can do these checks using positive look ahead assertions:

^(?=.*[A-Z].*[A-Z])(?=.*[!@#$&*])(?=.*[0-9].*[0-9])(?=.*[a-z].*[a-z].*[a-z]).{8}$

Rubular link

Explanation:

^                         Start anchor
(?=.*[A-Z].*[A-Z])        Ensure string has two uppercase letters.
(?=.*[!@#$&*])            Ensure string has one special case letter.
(?=.*[0-9].*[0-9])        Ensure string has two digits.
(?=.*[a-z].*[a-z].*[a-z]) Ensure string has three lowercase letters.
.{8}                      Ensure string is of length 8.
$                         End anchor.

Rounding SQL DateTime to midnight

Here is the simplest thing I've found

-- Midnight floor of current date

SELECT Convert(DateTime, DATEDIFF(DAY, 0, GETDATE()))

The DATEDIFF returns the integer number of days before or since 1900-1-1, and the Convert Datetime obligingly brings it back to that date at midnight.

Since DateDiff returns an integer you can use add or subtract days to get the right offset.

SELECT Convert(DateTime, DATEDIFF(DAY, 0, GETDATE()) + @dayOffset)

This isn't rounding this is truncating...But I think that is what is being asked. (To round add one and truncate...and that's not rounding either, that the ceiling, but again most likely what you want. To really round add .5 (does that work?) and truncate.

It turns out you can add .5 to GetDate() and it works as expected.

-- Round Current time to midnight today or midnight tomorrow

SELECT Convert(DateTime, DATEDIFF(DAY, 0, GETDATE() + .5))

I did all my trials on SQL Server 2008, but I think these functions apply to 2005 as well.

Display filename before matching line

grep 'search this' *.txt

worked for me to search through all .txt files (enter your own search value, of course).

Batch file to copy directories recursively

You may write a recursive algorithm in Batch that gives you exact control of what you do in every nested subdirectory:

@echo off
call :treeProcess
goto :eof

:treeProcess
rem Do whatever you want here over the files of this subdir, for example:
copy *.* C:\dest\dir
for /D %%d in (*) do (
    cd %%d
    call :treeProcess
    cd ..
)
exit /b

Windows Batch File Looping Through Directories to Process Files?

How to convert C# nullable int to int

You could do

v2 = v1.HasValue ? v1.Value : v2;

How to list all functions in a Python module?

For global functions dir() is the command to use (as mentioned in most of these answers), however this lists both public functions and non-public functions together.

For example running:

>>> import re
>>> dir(re)

Returns functions/classes like:

'__all__', '_MAXCACHE', '_alphanum_bytes', '_alphanum_str', '_pattern_type', '_pickle', '_subx'

Some of which are not generally meant for general programming use (but by the module itself, except in the case of DunderAliases like __doc__, __file__ ect). For this reason it may not be useful to list them with the public ones (this is how Python knows what to get when using from module import *).

__all__ could be used to solve this problem, it returns a list of all the public functions and classes in a module (those that do not start with underscores - _). See Can someone explain __all__ in Python? for the use of __all__.

Here is an example:

>>> import re
>>> re.__all__
['match', 'fullmatch', 'search', 'sub', 'subn', 'split', 'findall', 'finditer', 'compile', 'purge', 'template', 'escape', 'error', 'A', 'I', 'L', 'M', 'S', 'X', 'U', 'ASCII', 'IGNORECASE', 'LOCALE', 'MULTILINE', 'DOTALL', 'VERBOSE', 'UNICODE']
>>>

All the functions and classes with underscores have been removed, leaving only those that are defined as public and can therefore be used via import *.

Note that __all__ is not always defined. If it is not included then an AttributeError is raised.

A case of this is with the ast module:

>>> import ast
>>> ast.__all__
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
AttributeError: module 'ast' has no attribute '__all__'
>>>

When to use "ON UPDATE CASCADE"

It's an excellent question, I had the same question yesterday. I thought about this problem, specifically SEARCHED if existed something like "ON UPDATE CASCADE" and fortunately the designers of SQL had also thought about that. I agree with Ted.strauss, and I also commented Noran's case.

When did I use it? Like Ted pointed out, when you are treating several databases at one time, and the modification in one of them, in one table, has any kind of reproduction in what Ted calls "satellite database", can't be kept with the very original ID, and for any reason you have to create a new one, in case you can't update the data on the old one (for example due to permissions, or in case you are searching for fastness in a case that is so ephemeral that doesn't deserve the absolute and utter respect for the total rules of normalization, simply because will be a very short-lived utility)

So, I agree in two points:

(A.) Yes, in many times a better design can avoid it; BUT

(B.) In cases of migrations, replicating databases, or solving emergencies, it's a GREAT TOOL that fortunately was there when I went to search if it existed.

How to export data with Oracle SQL Developer?

To export data you need to right click on your results and select export data, after which you will be asked for a specific file format such as insert, loader, or text etc. After selecting this browse your directory and select the export destination.

How do I get the different parts of a Flask request's url?

another example:

request:

curl -XGET http://127.0.0.1:5000/alert/dingding/test?x=y

then:

request.method:              GET
request.url:                 http://127.0.0.1:5000/alert/dingding/test?x=y
request.base_url:            http://127.0.0.1:5000/alert/dingding/test
request.url_charset:         utf-8
request.url_root:            http://127.0.0.1:5000/
str(request.url_rule):       /alert/dingding/test
request.host_url:            http://127.0.0.1:5000/
request.host:                127.0.0.1:5000
request.script_root:
request.path:                /alert/dingding/test
request.full_path:           /alert/dingding/test?x=y

request.args:                ImmutableMultiDict([('x', 'y')])
request.args.get('x'):       y

How can I change an element's class with JavaScript?

You could also just do:

document.getElementById('id').classList.add('class');
document.getElementById('id').classList.remove('class');

And to toggle a class (remove if exists else add it):

document.getElementById('id').classList.toggle('class');

How do I add options to a DropDownList using jQuery?

With the plugin: jQuery Selection Box. You can do this:

var myOptions = {
        "Value 1" : "Text 1",
        "Value 2" : "Text 2",
        "Value 3" : "Text 3"
    }
    $("#myselect2").addOption(myOptions, false); 

No 'Access-Control-Allow-Origin' header in Angular 2 app

I also encountered the same problem and passed the following way to solve this problem.

step 1:

$ npm install --save-dev http-proxy-middleware

step 2:

add a proxy when i fetch web api, if you use lite-server you can add a file bs-config.js .

//file: bs-config.js
var proxyMiddleware = require('http-proxy-middleware');

module.exports = {
    server: {
        middleware: {
            1: proxyMiddleware('/example-api', {
                target: 'http://api.example.com',
                changeOrigin: true,
                pathRewrite: {
                '^/news-at-api': '/api'
                }
            })
        }
    }
};

hope this helps.

How to delete a whole folder and content?

Here is a non-recursive implementation, just for fun:

/**
 * Deletes the given folder and all its files / subfolders.
 * Is not implemented in a recursive way. The "Recursively" in the name stems from the filesystem command
 * @param root The folder to delete recursively
 */
public static void deleteRecursively(final File root) {
    LinkedList<File> deletionQueue = new LinkedList<>();
    deletionQueue.add(root);

    while(!deletionQueue.isEmpty()) {
        final File toDelete = deletionQueue.removeFirst();
        final File[] children = toDelete.listFiles();
        if(children == null || children.length == 0) {
            // This is either a file or an empty directory -> deletion possible
            toDelete.delete();
        } else {
            // Add the children before the folder because they have to be deleted first
            deletionQueue.addAll(Arrays.asList(children));
            // Add the folder again because we can't delete it yet.
            deletionQueue.addLast(toDelete);
        }
    }
}

String replace method is not replacing characters

And when I debug this the logic does fall into the sentence.replace.

Yes, and then you discard the return value.

Strings in Java are immutable - when you call replace, it doesn't change the contents of the existing string - it returns a new string with the modifications. So you want:

sentence = sentence.replace("and", " ");

This applies to all the methods in String (substring, toLowerCase etc). None of them change the contents of the string.

Note that you don't really need to do this in a condition - after all, if the sentence doesn't contain "and", it does no harm to perform the replacement:

String sentence = "Define, Measure, Analyze, Design and Verify";
sentence = sentence.replace("and", " ");

#1130 - Host ‘localhost’ is not allowed to connect to this MySQL server

Use the IP instead:

DROP USER 'root'@'127.0.0.1'; GRANT ALL PRIVILEGES ON . TO 'root'@'%';

For more possibilities, see this link.

To create the root user, seeing as MySQL is local & all, execute the following from the command line (Start > Run > "cmd" without quotes):

mysqladmin -u root password 'mynewpassword'

Documentation, and Lost root access in MySQL.

How to add a new row to an empty numpy array

The way to "start" the array that you want is:

arr = np.empty((0,3), int)

Which is an empty array but it has the proper dimensionality.

>>> arr
array([], shape=(0, 3), dtype=int64)

Then be sure to append along axis 0:

arr = np.append(arr, np.array([[1,2,3]]), axis=0)
arr = np.append(arr, np.array([[4,5,6]]), axis=0)

But, @jonrsharpe is right. In fact, if you're going to be appending in a loop, it would be much faster to append to a list as in your first example, then convert to a numpy array at the end, since you're really not using numpy as intended during the loop:

In [210]: %%timeit
   .....: l = []
   .....: for i in xrange(1000):
   .....:     l.append([3*i+1,3*i+2,3*i+3])
   .....: l = np.asarray(l)
   .....: 
1000 loops, best of 3: 1.18 ms per loop

In [211]: %%timeit
   .....: a = np.empty((0,3), int)
   .....: for i in xrange(1000):
   .....:     a = np.append(a, 3*i+np.array([[1,2,3]]), 0)
   .....: 
100 loops, best of 3: 18.5 ms per loop

In [214]: np.allclose(a, l)
Out[214]: True

The numpythonic way to do it depends on your application, but it would be more like:

In [220]: timeit n = np.arange(1,3001).reshape(1000,3)
100000 loops, best of 3: 5.93 µs per loop

In [221]: np.allclose(a, n)
Out[221]: True

How to pass a file path which is in assets folder to File(String path)?

Unless you unpack them, assets remain inside the apk. Accordingly, there isn't a path you can feed into a File. The path you've given in your question will work with/in a WebView, but I think that's a special case for WebView.

You'll need to unpack the file or use it directly.

If you have a Context, you can use context.getAssets().open("myfoldername/myfilename"); to open an InputStream on the file. With the InputStream you can use it directly, or write it out somewhere (after which you can use it with File).

Convert a binary NodeJS Buffer to JavaScript ArrayBuffer

This Proxy will expose the buffer as any of the TypedArrays, without any copy. :

https://www.npmjs.com/package/node-buffer-as-typedarray

It only works on LE, but can be easily ported to BE. Also, never got to actually test how efficient this is.

Java/ JUnit - AssertTrue vs AssertFalse

assertTrue will fail if the checked value is false, and assertFalse will do the opposite: fail if the checked value is true.

Another thing, your last assertEquals will very likely fail, as it will compare the "Book was already checked out" string with the output of m1.checkOut(b1,p2). It needs a third parameter (the second value to check for equality).

Remove the last three characters from a string

The new C# 8.0 range operator can be a great shortcut to achieve this.

Example #1 (to answer the question):

string myString = "abcdxxx";
var shortenedString = myString[0..^3]
System.Console.WriteLine(shortenedString);
// Results: abcd

Example #2 (to show you how awesome range operators are):

string s = "FooBar99";
// If the last 2 characters of the string are 99 then change to 98
s = s[^2..] == "99" ? s[0..^2] + "98" : s;
System.Console.WriteLine(s);
// Results: FooBar98

Import CSV to mysql table

Use TablePlus application: Right-Click on the table name from the right panel Choose Import... > From CSV Choose CSV file Review column matching and hit Import All done!

How to create a date and time picker in Android?

Here is a more compact version of Jaydeep's idea of showing one dialog after the other. I like this solution because it has no dependencies.

        Date value = new Date();
        final Calendar cal = Calendar.getInstance();
        cal.setTime(value);
        new DatePickerDialog(this,
            new DatePickerDialog.OnDateSetListener() {
                @Override public void onDateSet(DatePicker view, 
                        int y, int m, int d) {
                    cal.set(Calendar.YEAR, y);
                    cal.set(Calendar.MONTH, m);
                    cal.set(Calendar.DAY_OF_MONTH, d);

                    // now show the time picker
                    new TimePickerDialog(NoteEditor.this,
                        new TimePickerDialog.OnTimeSetListener() {
                            @Override public void onTimeSet(TimePicker view, 
                                    int h, int min) {
                                cal.set(Calendar.HOUR_OF_DAY, h);
                                cal.set(Calendar.MINUTE, min);
                                value = cal.getTime();
                            }
                        }, cal.get(Calendar.HOUR_OF_DAY), 
                            cal.get(Calendar.MINUTE), true).show();
                 }
            }, cal.get(Calendar.YEAR), cal.get(Calendar.MONTH),
            cal.get(Calendar.DAY_OF_MONTH)).show();

Android WebView, how to handle redirects in app instead of opening a browser

You will have to set your custom WebviewClient overriding shouldOverrideUrlLoading method for your webview before loading the url.

mWebView.setWebViewClient(new WebViewClient()
        {
            @SuppressWarnings("deprecation")
            @Override
            public boolean shouldOverrideUrlLoading(WebView webView, String url)
            {
                return shouldOverrideUrlLoading(url);
            }

            @TargetApi(Build.VERSION_CODES.N)
            @Override
            public boolean shouldOverrideUrlLoading(WebView webView, WebResourceRequest request)
            {
                Uri uri = request.getUrl();
                return shouldOverrideUrlLoading(uri.toString());
            }

            private boolean shouldOverrideUrlLoading(final String url)
            {
                Log.i(TAG, "shouldOverrideUrlLoading() URL : " + url);

                // Here put your code

                return true; // Returning True means that application wants to leave the current WebView and handle the url itself, otherwise return false.
            }
        });

Checkout the example code for handling redirect urls and open PDF without download, in webview. https://gist.github.com/ashishdas09/014a408f9f37504eb2608d98abf49500

auto refresh for every 5 mins

Install an interval:

<script type="text/javascript">    
    setInterval(page_refresh, 5*60000); //NOTE: period is passed in milliseconds
</script>

Share data between AngularJS controllers

There are multiple ways to do this.

  1. Events - already explained well.

  2. ui router - explained above.

  3. Service - with update method displayed above
  4. BAD - Watching for changes.
  5. Another parent child approach rather than emit and brodcast -

*

<superhero flight speed strength> Superman is here! </superhero>
<superhero speed> Flash is here! </superhero>

*

app.directive('superhero', function(){
    return {
        restrict: 'E',
        scope:{}, // IMPORTANT - to make the scope isolated else we will pollute it in case of a multiple components.
        controller: function($scope){
            $scope.abilities = [];
            this.addStrength = function(){
                $scope.abilities.push("strength");
            }
            this.addSpeed = function(){
                $scope.abilities.push("speed");
            }
            this.addFlight = function(){
                $scope.abilities.push("flight");
            }
        },
        link: function(scope, element, attrs){
            element.addClass('button');
            element.on('mouseenter', function(){
               console.log(scope.abilities);
            })
        }
    }
});
app.directive('strength', function(){
    return{
        require:'superhero',
        link: function(scope, element, attrs, superHeroCtrl){
            superHeroCtrl.addStrength();
        }
    }
});
app.directive('speed', function(){
    return{
        require:'superhero',
        link: function(scope, element, attrs, superHeroCtrl){
            superHeroCtrl.addSpeed();
        }
    }
});
app.directive('flight', function(){
    return{
        require:'superhero',
        link: function(scope, element, attrs, superHeroCtrl){
            superHeroCtrl.addFlight();
        }
    }
});

Changing background colour of tr element on mouseover

This will work:

tr:hover {
    background: #000 !important;
}

If you want to only apply bg-color on TD then:

tr:hover td {
    background: #c7d4dd !important;
}

It will even overwrite your given color and apply this forcefully.

jQuery UI Slider (setting programmatically)

One part of @gaurav solution worked for jQuery 2.1.3 and JQuery UI 1.10.2 with multiple sliders. My project is using four range sliders to filter data with this filter.js plugin. Other solutions were resetting the slider handles back to their starting end points just fine, but apparently they were not firing an event that filter.js understood. So here's how I looped through the sliders:

$("yourSliderSelection").each (function () {
    var hs = $(this); 
    var options = $(this).slider('option');

    //reset the ui
    $(this).slider( 'values', [ options.min, options.max ] ); 

    //refresh/trigger event so that filter.js can reset handling the data
    hs.slider('option', 'slide').call(
        hs, 
        null, 
        {
            handle: $('.ui-slider-handle', hs),
            values: [options.min, options.max]
        }
    );

});

The hs.slider() code resets the data, but not the UI in my scenario. Hope this helps others.

How to check if an object is a certain type

In VB.NET, you need to use the GetType method to retrieve the type of an instance of an object, and the GetType() operator to retrieve the type of another known type.

Once you have the two types, you can simply compare them using the Is operator.

So your code should actually be written like this:

Sub FillCategories(ByVal Obj As Object)
    Dim cmd As New SqlCommand("sp_Resources_Categories", Conn)
    cmd.CommandType = CommandType.StoredProcedure
    Obj.DataSource = cmd.ExecuteReader
    If Obj.GetType() Is GetType(System.Web.UI.WebControls.DropDownList) Then

    End If
    Obj.DataBind()
End Sub

You can also use the TypeOf operator instead of the GetType method. Note that this tests if your object is compatible with the given type, not that it is the same type. That would look like this:

If TypeOf Obj Is System.Web.UI.WebControls.DropDownList Then

End If

Totally trivial, irrelevant nitpick: Traditionally, the names of parameters are camelCased (which means they always start with a lower-case letter) when writing .NET code (either VB.NET or C#). This makes them easy to distinguish at a glance from classes, types, methods, etc.

Typescript: No index signature with a parameter of type 'string' was found on type '{ "A": string; }

Here is the function example trim generic type of array object

const trimArrayObject = <T>(items: T[]) => {

  items.forEach(function (o) {

    for (let [key, value] of Object.entries(o)) {

      const keyName = <keyof typeof o>key;

      if (Array.isArray(value)) {

        trimArrayObject(value);

      } else if (typeof o[keyName] === "string") {

        o[keyName] = value.trim();

      }

    }

  });

};

How to add certificate chain to keystore?

I solved the problem by cat'ing all the pems together:

cat cert.pem chain.pem fullchain.pem >all.pem
openssl pkcs12 -export -in all.pem -inkey privkey.pem -out cert_and_key.p12 -name tomcat -CAfile chain.pem -caname root -password MYPASSWORD
keytool -importkeystore -deststorepass MYPASSWORD -destkeypass MYPASSWORD -destkeystore MyDSKeyStore.jks -srckeystore cert_and_key.p12 -srcstoretype PKCS12 -srcstorepass MYPASSWORD -alias tomcat
keytool -import -trustcacerts -alias root -file chain.pem -keystore MyDSKeyStore.jks -storepass MYPASSWORD

(keytool didn't know what to do with a PKCS7 formatted key)

I got all the pems from letsencrypt

Spring Boot Java Config Set Session Timeout

  • Spring Boot version 1.0: server.session.timeout=1200
  • Spring Boot version 2.0: server.servlet.session.timeout=10m
    NOTE: If a duration suffix is not specified, seconds will be used.

Stop fixed position at footer

If your elements are glitching this is probably because when you change the position to relative the Y position of the footer increases which tries to send the item back to fixed which creates a loop. You can avoid this by setting two different cases when scrolling up and down. You don't even need to reference the fixed element, just the footer, and window size.

const footer = document.querySelector('footer');
document.addEventListener("scroll", checkScroll);

let prevY = window.scrollY + window.innerHeight;
function checkScroll() {
  let footerTop = getRectTop(footer) + window.scrollY;
  let windowBottomY = window.scrollY + window.innerHeight;
  if (prevY < windowBottomY) {  // Scroll Down
    if (windowBottomY > footerTop)
      setScrolledToFooter(true) // using React state. Change class or change style in JS.
  } else { // Scroll Up
    if (windowBottomY <= footerTop)
      setScrolledToFooter(false)
  }
  prevY = windowBottomY
};

function getRectTop(el) {
  var rect = el.getBoundingClientRect();
  return rect.top;
}

and the position of the element in the style object as follows:

position: scrolledToFooter ? 'relative' : 'fixed'

$(document).on('click', '#id', function() {}) vs $('#id').on('click', function(){})

Consider following code

<ul id="myTask">
  <li>Coding</li>
  <li>Answering</li>
  <li>Getting Paid</li>
</ul>

Now, here goes the difference

// Remove the myTask item when clicked.
$('#myTask').children().click(function () {
  $(this).remove()
});

Now, what if we add a myTask again?

$('#myTask').append('<li>Answer this question on SO</li>');

Clicking this myTask item will not remove it from the list, since it doesn't have any event handlers bound. If instead we'd used .on, the new item would work without any extra effort on our part. Here's how the .on version would look:

$('#myTask').on('click', 'li', function (event) {
  $(event.target).remove()
});

Summary:

The difference between .on() and .click() would be that .click() may not work when the DOM elements associated with the .click() event are added dynamically at a later point while .on() can be used in situations where the DOM elements associated with the .on() call may be generated dynamically at a later point.

grep --ignore-case --only

I'd suggest that the -i means it does match "ABC", but the difference is in the output. -i doesn't manipulate the input, so it won't change "ABC" to "abc" because you specified "abc" as the pattern. -o says it only shows the part of the output that matches the pattern specified, it doesn't say about matching input.

The output of echo "ABC" | grep -i abc is ABC, the -o shows output matching "abc" so nothing shows:

Naos:~ mattlacey$ echo "ABC" | grep -i abc | grep -o abc
Naos:~ mattlacey$ echo "ABC" | grep -i abc | grep -o ABC
ABC

npm install from Git in a specific version

A dependency has to be available from the registry to be installed just by specifying a version descriptor.

You can certainly create and use your own registry instead of registry.npmjs.org if your projects shouldn't be shared publicly.

But, if it's not in a registry, it'll have to be referenced by URL or Git URL. To specify a version with a Git URL, include an appropriate <commit-ish>, such as a tag, at the end as a URL fragment.

Example, for a tag named 0.3.1:

"dependencies": {
  "myprivatemodule": "[email protected]:...#0.3.1"
}

Note: The above snippet shows the base URL the same as it was posted in the question.

The snipped portion (...) should be filled in:

"myprivatemodule": "[email protected]:{owner}/{project}.git#0.3.1"

And, a different address format will be needed when SSH access isn't available:

"myprivatemodule": "git://github.com/{owner}/{project}.git#0.3.1"

Depending on your OS, you may also be able to link to the dependency in another folder where you have it cloned from Github.

Is there a function in python to split a word into a list?

The list function will do this

>>> list('foo')
['f', 'o', 'o']

"npm config set registry https://registry.npmjs.org/" is not working in windows bat file

Probably I am too late to answer. But if anybody need it, following works fine, as I have used it a lot of times.

npm config set registry=https://registry.npmjs.com/

How to sort an STL vector?

Overload less than operator, then sort. This is an example I found off the web...

class MyData
{
public:
  int m_iData;
  string m_strSomeOtherData;
  bool operator<(const MyData &rhs) const { return m_iData < rhs.m_iData; }
};

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

Source: here

How to install the Raspberry Pi cross compiler on my Linux host machine?

I'm gonna try to write this as a tutorial for you so it becomes easy to follow.

NOTE: This tutorial only works for older raspbian images. For the newer Raspbian based on Debian Buster see the following how-to in this thread: https://stackoverflow.com/a/58559140/869402

Pre-requirements

Before you start you need to make sure the following is installed:

apt-get install git rsync cmake libc6-i386 lib32z1 lib32stdc++6

Let's cross compile a Pie!

Start with making a folder in your home directory called raspberrypi.

Go in to this folder and pull down the ENTIRE tools folder you mentioned above:

git clone git://github.com/raspberrypi/tools.git

You wanted to use the following of the 3 ones, gcc-linaro-arm-linux-gnueabihf-raspbian, if I did not read wrong.

Go into your home directory and add:

export PATH=$PATH:$HOME/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin

to the end of the file named ~/.bashrc

Now you can either log out and log back in (i.e. restart your terminal session), or run . ~/.bashrc in your terminal to pick up the PATH addition in your current terminal session.

Now, verify that you can access the compiler arm-linux-gnueabihf-gcc -v. You should get something like this:

Using built-in specs.
COLLECT_GCC=arm-linux-gnueabihf-gcc
COLLECT_LTO_WRAPPER=/home/tudhalyas/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/../libexec/gcc/arm-linux-gnueabihf/4.7.2/lto-wrapper
Target: arm-linux-gnueabihf
Configured with: /cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.b
 uild/src/gcc-linaro-4.7-2012.08/configure --build=i686-build_pc-linux-gnu --host=i686-build_pc-
 linux-gnu --target=arm-linux-gnueabihf --prefix=/cbuild/slaves/oort61/crosstool-ng/builds/arm-l
 inux-gnueabihf-raspbian-linux/install --with-sysroot=/cbuild/slaves/oort61/crosstool-ng/builds/
 arm-linux-gnueabihf-raspbian-linux/install/arm-linux-gnueabihf/libc --enable-languages=c,c++,fo
 rtran --disable-multilib --with-arch=armv6 --with-tune=arm1176jz-s --with-fpu=vfp --with-float=
 hard --with-pkgversion='crosstool-NG linaro-1.13.1+bzr2458 - Linaro GCC 2012.08' --with-bugurl=
 https://bugs.launchpad.net/gcc-linaro --enable-__cxa_atexit --enable-libmudflap --enable-libgom
 p --enable-libssp --with-gmp=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-rasp
 bian-linux/.build/arm-linux-gnueabihf/build/static --with-mpfr=/cbuild/slaves/oort61/crosstool-
 ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-mpc
 =/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-
 gnueabihf/build/static --with-ppl=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf
 -raspbian-linux/.build/arm-linux-gnueabihf/build/static --with-cloog=/cbuild/slaves/oort61/cros
 stool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static --wi
 th-libelf=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-linux/.build/a
 rm-linux-gnueabihf/build/static --with-host-libstdcxx='-L/cbuild/slaves/oort61/crosstool-ng/bui
 lds/arm-linux-gnueabihf-raspbian-linux/.build/arm-linux-gnueabihf/build/static/lib -lpwl' --ena
 ble-threads=posix --disable-libstdcxx-pch --enable-linker-build-id --enable-plugin --enable-gol
 d --with-local-prefix=/cbuild/slaves/oort61/crosstool-ng/builds/arm-linux-gnueabihf-raspbian-li
 nux/install/arm-linux-gnueabihf/libc --enable-c99 --enable-long-long
Thread model: posix
gcc version 4.7.2 20120731 (prerelease) (crosstool-NG linaro-1.13.1+bzr2458 - Linaro GCC 2012.08
 )

But hey! I did that and the libs still don't work!

We're not done yet! So far, we've only done the basics.

In your raspberrypi folder, make a folder called rootfs.

Now you need to copy the entire /liband /usr directory to this newly created folder. I usually bring the rpi image up and copy it via rsync:

rsync -rl --delete-after --safe-links [email protected]:/{lib,usr} $HOME/raspberrypi/rootfs

where 192.168.1.PI is replaced by the IP of your Raspberry Pi.

Now, we need to write a cmake config file. Open ~/home/raspberrypi/pi.cmake in your favorite editor and insert the following:

SET(CMAKE_SYSTEM_NAME Linux)
SET(CMAKE_SYSTEM_VERSION 1)
SET(CMAKE_C_COMPILER $ENV{HOME}/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-gcc)
SET(CMAKE_CXX_COMPILER $ENV{HOME}/raspberrypi/tools/arm-bcm2708/gcc-linaro-arm-linux-gnueabihf-raspbian/bin/arm-linux-gnueabihf-g++)
SET(CMAKE_FIND_ROOT_PATH $ENV{HOME}/raspberrypi/rootfs)
SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

Now you should be able to compile your cmake programs simply by adding this extra flag: -D CMAKE_TOOLCHAIN_FILE=$HOME/raspberrypi/pi.cmake.

Using a cmake hello world example:

git clone https://github.com/jameskbride/cmake-hello-world.git 
cd cmake-hello-world
mkdir build
cd build
cmake -D CMAKE_TOOLCHAIN_FILE=$HOME/raspberrypi/pi.cmake ../
make
scp CMakeHelloWorld [email protected]:/home/pi/
ssh [email protected] ./CMakeHelloWorld

Show pop-ups the most elegant way

Based on my experience with AngularJS modals so far I believe that the most elegant approach is a dedicated service to which we can provide a partial (HTML) template to be displayed in a modal.

When we think about it modals are kind of AngularJS routes but just displayed in modal popup.

The AngularUI bootstrap project (http://angular-ui.github.com/bootstrap/) has an excellent $modal service (used to be called $dialog prior to version 0.6.0) that is an implementation of a service to display partial's content as a modal popup.

How to correctly use Html.ActionLink with ASP.NET MVC 4 Areas

How I redirect to an area is add it as a parameter

@Html.Action("Action", "Controller", new { area = "AreaName" })

for the href portion of a link I use

@Url.Action("Action", "Controller", new { area = "AreaName" })

Batch program to to check if process exists

TASKLIST does not set errorlevel.

echo off
tasklist /fi "imagename eq notepad.exe" |find ":" > nul
if errorlevel 1 taskkill /f /im "notepad.exe"
exit

should do the job, since ":" should appear in TASKLIST output only if the task is NOT found, hence FIND will set the errorlevel to 0 for not found and 1 for found

Nevertheless,

taskkill /f /im "notepad.exe"

will kill a notepad task if it exists - it can do nothing if no notepad task exists, so you don't really need to test - unless there's something else you want to do...like perhaps

echo off
tasklist /fi "imagename eq notepad.exe" |find ":" > nul
if errorlevel 1 taskkill /f /im "notepad.exe"&exit

which would appear to do as you ask - kill the notepad process if it exists, then exit - otherwise continue with the batch

Button Listener for button in fragment in android

Your fragment class should implement OnClickListener

public class SmartTvControllerFragment extends Fragment implements View.OnClickListener

Then get view, link button and set onClickListener like in example below

 View view;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    view = inflater.inflate(R.layout.smart_tv_controller_fragment, container, false);
    upButton = (Button) view.findViewById(R.id.smart_tv_controller_framgment_up_button);
    upButton.setOnClickListener(this);
    return view;
 }

And then add onClickListener method and do what you want.

@Override
public void onClick(View v) {
 //do what you want to do when button is clicked
    switch (v.getId()) {
        case R.id.textView_help:
            switchFragment(HelpFragment.TAG);
            break;
        case R.id.textView_settings:
            switchFragment(SettingsFragment.TAG);
            break;
    }
}

This is my example of code, but I hope you understood

Making view resize to its parent when added with addSubview

If you aren’t using Auto Layout, have you tried setting the child view’s autoresize mask? Try this:

myChildeView.autoresizingMask = (UIViewAutoresizingFlexibleWidth |
                                 UIViewAutoresizingFlexibleHeight);

Also, you may need to call

myParentView.autoresizesSubviews = YES;

to get the parent view to resize its subviews automatically when its frame changes.

If you’re still seeing the child view drawing outside of the parent view’s frame, there’s a good chance that the parent view is not clipping its contents. To fix that, call

myParentView.clipsToBounds = YES;

How to check Spark Version

According to the Cloudera documentation - What's New in CDH 5.7.0 it includes Spark 1.6.0.

Ansible: get current target host's IP address

http://docs.ansible.com/ansible/latest/plugins/lookup/dig.html

so in template, for e. g.:

{{ lookup('dig', ansible_host) }}

Notes:

  • Since not only DNS name could be used in inventory a check if it's not IP already better be added
  • Obviously enough this receipt wouldn't work as intended for indirect host specifications (like using jump hosts, for e. g.)

But still it serves 99 % (figuratively speaking) of use cases.

JQuery Parsing JSON array

with parse.JSON

var obj = jQuery.parseJSON( '{ "name": "John" }' );
alert( obj.name === "John" );

How do I print bytes as hexadecimal?

This is a modified version of the Nibble to Hex method

void hexArrayToStr(unsigned char* info, unsigned int infoLength, char **buffer) {
    const char* pszNibbleToHex = {"0123456789ABCDEF"};
    int nNibble, i;
    if (infoLength > 0) {
        if (info != NULL) {
            *buffer = (char *) malloc((infoLength * 2) + 1);
            buffer[0][(infoLength * 2)] = 0;
            for (i = 0; i < infoLength; i++) {
                nNibble = info[i] >> 4;
                buffer[0][2 * i] = pszNibbleToHex[nNibble];
                nNibble = info[i] & 0x0F;
                buffer[0][2 * i + 1] = pszNibbleToHex[nNibble];
            }
        } else {
            *buffer = NULL;
        }
    } else {
        *buffer = NULL;
    }
}

Run function from the command line

It is always an option to enter python on the command line with the command python

then import your file so import example_file

then run the command with example_file.hello()

This avoids the weird .pyc copy function that crops up every time you run python -c etc.

Maybe not as convenient as a single-command, but a good quick fix to text a file from the command line, and allows you to use python to call and execute your file.

Preloading CSS Images

For preloading background images set with CSS, the most efficient answer i came up with was a modified version of some code I found that did not work:

$(':hidden').each(function() {
  var backgroundImage = $(this).css("background-image");
  if (backgroundImage != 'none') {
    tempImage = new Image();
    tempImage.src = backgroundImage;
  }
});

The massive benefit of this is that you don't need to update it when you bring in new background images in the future, it will find the new ones and preload them!

Connection Java-MySql : Public Key Retrieval is not allowed

When doing this from DBeaver I had to go to "Connection settings" -> "SSL" tab and then :

  • uncheck the "Verify server certificate"
  • check the "Allow public key retrival"

This is how it looks like. DBeaver configuration

Note that this is suitable for local development only.

How do I return a char array from a function?

When you create local variables inside a function that are created on the stack, they most likely get overwritten in memory when exiting the function.

So code like this in most C++ implementations will not work:

char[] populateChar()
{
    char* ch = "wonet return me";
    return ch;
}

A fix is to create the variable that want to be populated outside the function or where you want to use it, and then pass it as a parameter and manipulate the function, example:

void populateChar(char* ch){
    strcpy(ch, "fill me, Will. This will stay", size); // This will work as long as it won't overflow it.
}

int main(){
    char ch[100]; // Reserve memory on the stack outside the function
    populateChar(ch); // Populate the array
}

A C++11 solution using std::move(ch) to cast lvalues to rvalues:

void populateChar(char* && fillme){
    fillme = new char[20];
    strcpy(fillme, "this worked for me");
}

int main(){
    char* ch;
    populateChar(std::move(ch));
    return 0;
}

Or this option in C++11:

char* populateChar(){
    char* ch = "test char";
    // Will change from lvalue to r value
    return std::move(ch);
}

int main(){
    char* ch = populateChar();
    return 0;
}

Segmentation Fault - C

Even better

#include <stdio.h>
int
main(void)
{
  char *line = NULL;
  size_t count;
  char *dup_line;

  getline(&line,&count, stdin);
  dup_line=strdup(line);

  puts(dup_line);

  free(dup_line);
  free(line);

  return 0;
}

Ruby on Rails 3 Can't connect to local MySQL server through socket '/tmp/mysql.sock' on OSX

Found it!

Change host: localhost in config/database.yml to host: 127.0.0.1 to make rails connect over TCP/IP instead of local socket.

development:
  adapter: mysql2
  host: 127.0.0.1
  username: root
  password: xxxx
  database: xxxx

AndroidStudio: Failed to sync Install build tools

I was also facing the same problem with gradle. Now I have solved by installing the highlighted in red. To navigate on this page Open Android studio > Tool > Android > SDK Manager > Appearance & Behavior > System Settings > Android SDK > SDK Tools (from tab options) > Show Package details(check box on the right bottom corner). After installing these just refresh the gradle everything will be resolved.sdk download screenshot

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

I've changed the recursion to iteration.

def MovingTheBall(listOfBalls,position,numCell):
while 1:
    stop=1
    positionTmp = (position[0]+choice([-1,0,1]),position[1]+choice([-1,0,1]),0)
    for i in range(0,len(listOfBalls)):
        if positionTmp==listOfBalls[i].pos:
            stop=0
    if stop==1:
        if (positionTmp[0]==0 or positionTmp[0]>=numCell or positionTmp[0]<=-numCell or positionTmp[1]>=numCell or positionTmp[1]<=-numCell):
            stop=0
        else:
            return positionTmp

Works good :D

OpenCV in Android Studio

For everyone who felt they want to run away with all the steps and screen shots on the (great!) above answers, this worked for me with android studio 2.2.1:

  1. Create a new project, name it as you want and take the default (minSdkVersion 15 is fine).

  2. Download the zip file from here: https://sourceforge.net/projects/opencvlibrary/files/opencv-android/ (I downloaded 3.2.0 version, but there may be a newer versions).

  3. Unzip the zip file, the best place is in your workspace folder, but it not really matter.

  4. Inside Android Studio, click File->New-> Import Module and navigate to \path_to_your_unzipped_file\OpenCV-android-sdk\sdk\java and hit Ok, then accept all default dialogs.

  5. In the gradle file of your app module, add this to the dependencies block:

     dependencies {
         compile project(':openCVLibraryXYZ')
         //rest of code
     }
    

Where XYZ is the exact version you downloaded, for example in my case:

    dependencies {
        compile project(':openCVLibrary320')
        //rest of code
    }

How to make a flex item not fill the height of the flex container?

The align-items, or respectively align-content attribute controls this behaviour.

align-items defines the items' positioning perpendicularly to flex-direction.

The default flex-direction is row, therfore vertical placement can be controlled with align-items.

There is also the align-self attribute to control the alignment on a per item basis.

_x000D_
_x000D_
#a {_x000D_
  display:flex;_x000D_
_x000D_
  align-items:flex-start;_x000D_
  align-content:flex-start;_x000D_
  }_x000D_
_x000D_
#a > div {_x000D_
  _x000D_
  background-color:red;_x000D_
  padding:5px;_x000D_
  margin:2px;_x000D_
  }_x000D_
 #a > #c {_x000D_
  align-self:stretch;_x000D_
 }
_x000D_
<div id="a">_x000D_
  _x000D_
  <div id="b">left</div>_x000D_
  <div id="c">middle</div>_x000D_
  <div>right<br>right<br>right<br>right<br>right<br></div>_x000D_
  _x000D_
</div>
_x000D_
_x000D_
_x000D_

css-tricks has an excellent article on the topic. I recommend reading it a couple of times.

jQuery - how to check if an element exists?

Mostly, I prefer to use this syntax :

if ($('#MyId')!= null) {
    // dostuff
}

Even if this code is not commented, the functionality is obvious.

Android list view inside a scroll view

best Code

 <android.support.v4.widget.NestedScrollView
    android:id="@+id/scrollView1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_above="@+id/btmlyt"
    android:layout_below="@+id/deshead_tv">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
       android:orientation="vertical"
       >

    <TextView
        android:id="@+id/des_tv"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_above="@+id/btmlyt"
        android:background="@android:color/white"
        android:paddingLeft="3dp"
        android:paddingRight="3dp"
        android:scrollbars="vertical"
        android:paddingTop="3dp"
        android:text="description"
        android:textColor="@android:color/black"
        android:textSize="18sp" />
    </LinearLayout>

</android.support.v4.widget.NestedScrollView>

What is the recommended project structure for spring boot rest projects?

There is a somehow recommended directory structure mentioned at https://docs.spring.io/spring-boot/docs/current/reference/html/using-boot-structuring-your-code.html

You can create a api folder and put your controllers there.

If you have some configuration beans, put them in a separate package too.

Eclipse "Invalid Project Description" when creating new project from existing source

I've been having this problem in Linux, with a project that I renamed, removed, and reimported. Somewhere in the .metadata, it's still there evidently.

I finally solved it by the following steps:

close Eclipse
mv .metadata .metadata_orig
start Eclipse
reset default workspace
reimport projects

This may not work for everyone, especially if you already have lots of projects in multiple workspaces. But if you're used to reconfiguring Eclipse (which I do every time I upgrade to the next Eclipse release) it's not too bad.

PHP error: php_network_getaddresses: getaddrinfo failed: (while getting information from other site.)

In the following httpd.conf file, configure the ServerName properly.

/etc/httpd/conf/httpd.conf

Like below:

ServerName 127.0.0.1:80

or

ServerName sitename

This resolved similar issue I was facing.

pip install from git repo branch

Just to add an extra, if you want to install it in your pip file it can be added like this:

-e git+https://github.com/tangentlabs/django-oscar-paypal.git@issue/34/oscar-0.6#egg=django-oscar-paypal

It will be saved as an egg though.

"Unable to get the VLookup property of the WorksheetFunction Class" error

I was having the same problem. It seems that passing Me.ComboBox1.Value as an argument for the Vlookup function is causing the issue. What I did was assign this value to a double and then put it into the Vlookup function.

Dim x As Double
x = Me.ComboBox1.Value
Me.TextBox1.Value = Application.WorksheetFunction.VLookup(x, Worksheets("Sheet3").Range("Names"), 2, False) 

Or, for a shorter method, you can just convert the type within the Vlookup function using Cdbl(<Value>).

So it would end up being

Me.TextBox1.Value = Application.WorksheetFunction.VLookup(Cdbl(Me.ComboBox1.Value), Worksheets("Sheet3").Range("Names"), 2, False) 

Strange as it may sound, it works for me.

Hope this helps.

What ports need to be open for TortoiseSVN to authenticate (clear text) and commit?

What's the first part of your Subversion repository URL?

  • If your URL looks like: http://subversion/repos/, then you're probably going over Port 80.
  • If your URL looks like: https://subversion/repos/, then you're probably going over Port 443.
  • If your URL looks like: svn://subversion/, then you're probably going over Port 3690.
  • If your URL looks like: svn+ssh://subversion/repos/, then you're probably going over Port 22.
  • If your URL contains a port number like: http://subversion/repos:8080, then you're using that port.

I can't guarantee the first four since it's possible to reconfigure everything to use different ports, of if you go through a proxy of some sort.

If you're using a VPN, you may have to configure your VPN client to reroute these to their correct ports. A lot of places don't configure their correctly VPNs to do this type of proxying. It's either because they have some sort of anal-retentive IT person who's being overly security conscious, or because they simply don't know any better. Even worse, they'll give you a client where this stuff can't be reconfigured.

The only way around that is to log into a local machine over the VPN, and then do everything from that system.

Difference between jQuery .hide() and .css("display", "none")

Yes there is a difference in the performance of both: jQuery('#id').show() is slower than jQuery('#id').css("display","block") as in former case extra work is to be done for retrieving the initial state from the jquery cache as display is not a binary attribute it can be inline,block,none,table, etc. similar is the case with hide() method.

See: http://jsperf.com/show-vs-addclass

Expand div to max width when float:left is set

Solution without fixing size on your margin

.content .right{
    overflow: auto; 
    background-color: red;
}

+1 for Merkuro, but if the size of the float changes your fixed margin will fail. If u use above CSS on the right div it will nicely change size with changing size on the left float. It is a bit more flexible like that. Check the fiddle here: http://jsfiddle.net/9ZHBK/144/

Setting custom UITableViewCells height

in a custom UITableViewCell -controller add this

-(void)layoutSubviews {  

    CGRect newCellSubViewsFrame = CGRectMake(0, 0, self.frame.size.width, self.frame.size.height);
    CGRect newCellViewFrame = CGRectMake(self.frame.origin.x, self.frame.origin.y, self.frame.size.width, self.frame.size.height);

    self.contentView.frame = self.contentView.bounds = self.backgroundView.frame = self.accessoryView.frame = newCellSubViewsFrame;
    self.frame = newCellViewFrame;

    [super layoutSubviews];
}

In the UITableView -controller add this

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return [indexPath row] * 1.5; // your dynamic height...
}

How do I convert a PDF document to a preview image in PHP?

You can also get the page count using

$im->getNumberImages();

Then you can can create thumbs of all the pages using a loop, eg.

'file.pdf['.$x.']'

What is the difference between signed and unsigned int

In laymen's terms an unsigned int is an integer that can not be negative and thus has a higher range of positive values that it can assume. A signed int is an integer that can be negative but has a lower positive range in exchange for more negative values it can assume.

Populating a ComboBox using C#

No need to use a particular class Language,

Just replace it with :

KeyValuePair<string,string>

Run react-native on android emulator

On macOs I manage to fix this by adding:

export ANDROID_HOME=$HOME/Library/Android/sdk
export PATH=$PATH:$ANDROID_HOME/emulator
export PATH=$PATH:$ANDROID_HOME/tools
export PATH=$PATH:$ANDROID_HOME/tools/bin
export PATH=$PATH:$ANDROID_HOME/platform-tools

to ~/.zsh_profile file.

and than type to your terminal

source $HOME/.zsh_profile

The issue was caused by using iTerm2 shell so it's required to edit its own config instead of default $HOME/.bash_profile as described in the official documentation https://reactnative.dev/docs/environment-setup

Running AngularJS initialization code when view is loaded

Since AngularJS 1.5 we should use $onInit which is available on any AngularJS component. Taken from the component lifecycle documentation since v1.5 its the preffered way:

$onInit() - Called on each controller after all the controllers on an element have been constructed and had their bindings initialized (and before the pre & post linking functions for the directives on this element). This is a good place to put initialization code for your controller.

var myApp = angular.module('myApp',[]);
myApp.controller('MyCtrl', function ($scope) {

    //default state
    $scope.name = '';

    //all your init controller goodness in here
    this.$onInit = function () {
      $scope.name = 'Superhero';
    }
});

>> Fiddle Demo


An advanced example of using component lifecycle:

The component lifecycle gives us the ability to handle component stuff in a good way. It allows us to create events for e.g. "init", "change" or "destroy" of an component. In that way we are able to manage stuff which is depending on the lifecycle of an component. This little example shows to register & unregister an $rootScope event listener $on. By knowing, that an event $on binded on $rootScope will not be undinded when the controller loses its reference in the view or getting destroyed we need to destroy a $rootScope.$on listener manually. A good place to put that stuff is $onDestroy lifecycle function of an component:

var myApp = angular.module('myApp',[]);

myApp.controller('MyCtrl', function ($scope, $rootScope) {

  var registerScope = null;

  this.$onInit = function () {
    //register rootScope event
    registerScope = $rootScope.$on('someEvent', function(event) {
        console.log("fired");
    });
  }

  this.$onDestroy = function () {
    //unregister rootScope event by calling the return function
    registerScope();
  }
});

>> Fiddle demo

Get value of c# dynamic property via string

To get properties from dynamic doc when .GetType() returns null, try this:

var keyValuePairs = ((System.Collections.Generic.IDictionary<string, object>)doc);
var val = keyValuePairs["propertyName"].ToObject<YourModel>;

Clearing localStorage in javascript?

First things first, you need to check to make sure that localStorage is enabled. I would recommend doing it like this:

var localStorageEnabled = false;
try { localStorageEnabled = !!localStorage; } catch(e) {};

Yes, you can (in some cases) just check to see if the localStorage is a member of the window object. However, there are iframe sandboxing options (among other things) that will throw an exception if you even attempt to access the index 'localStorage'. Thus, for best-practices reasons, this is the best way to check to see if the localStorage is enabled. Then, you can just clear the localStorage like so.

if (localStorageEnabled) localStorage.clear();

For example, you could clear the localStorage after an error occurs in webkit browsers like so.

// clears the local storage upon error
if (localStorageEnabled)
  window.onerror = localStorage.clear.bind(localStorage);

In the above example, you need the .bind(window) because without it, the localStorage.clear function will run in the context of the window object, instead of the localStorage object making it silently fail. To demonstrate this, look at the below example:

window.onerror = localStorage.clear;

is the same as:

window.onerror = function(){
    localStorage.clear.call(window);
}

How to install Python packages from the tar.gz file without using pip install

Install it by running

python setup.py install

Better yet, you can download from github. Install git via apt-get install git and then follow this steps:

git clone https://github.com/mwaskom/seaborn.git
cd seaborn
python setup.py install

How do I execute multiple SQL Statements in Access' Query Editor?

create a macro like this

Option Compare Database

Sub a()

DoCmd.RunSQL "DELETE * from TABLENAME where CONDITIONS"

DoCmd.RunSQL "DELETE * from TABLENAME where CONDITIONS"

End Sub

Error checking for NULL in VBScript

From your code, it looks like provider is a variant or some other variable, and not an object.

Is Nothing is for objects only, yet later you say it's a value that should either be NULL or NOT NULL, which would be handled by IsNull.

Try using:

If Not IsNull(provider) Then 
    url = url & "&provider=" & provider 
End if

Alternately, if that doesn't work, try:

If provider <> "" Then 
    url = url & "&provider=" & provider 
End if

HttpWebRequest using Basic authentication

One reason why the top answer and others wont work for you is because it is missing a critical line. (note many API manuals leave out this necessity)

request.PreAuthenticate = true;

Easiest way to convert a Blob into a byte array

The easiest way is this.

byte[] bytes = rs.getBytes("my_field");

How to calculate the 95% confidence interval for the slope in a linear regression model in R

Let's fit the model:

> library(ISwR)
> fit <- lm(metabolic.rate ~ body.weight, rmr)
> summary(fit)

Call:
lm(formula = metabolic.rate ~ body.weight, data = rmr)

Residuals:
    Min      1Q  Median      3Q     Max 
-245.74 -113.99  -32.05  104.96  484.81 

Coefficients:
            Estimate Std. Error t value Pr(>|t|)    
(Intercept) 811.2267    76.9755  10.539 2.29e-13 ***
body.weight   7.0595     0.9776   7.221 7.03e-09 ***
---
Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 

Residual standard error: 157.9 on 42 degrees of freedom
Multiple R-squared: 0.5539, Adjusted R-squared: 0.5433 
F-statistic: 52.15 on 1 and 42 DF,  p-value: 7.025e-09 

The 95% confidence interval for the slope is the estimated coefficient (7.0595) ± two standard errors (0.9776).

This can be computed using confint:

> confint(fit, 'body.weight', level=0.95)
               2.5 % 97.5 %
body.weight 5.086656 9.0324

Importing large sql file to MySql via command line

You can import .sql file using the standard input like this:

mysql -u <user> -p<password> <dbname> < file.sql

Note: There shouldn't space between <-p> and <password>

Reference: http://dev.mysql.com/doc/refman/5.0/en/mysql-batch-commands.html

Note for suggested edits: This answer was slightly changed by suggested edits to use inline password parameter. I can recommend it for scripts but you should be aware that when you write password directly in the parameter (-p<password>) it may be cached by a shell history revealing your password to anyone who can read the history file. Whereas -p asks you to input password by standard input.

-bash: export: `=': not a valid identifier

First of all go to the /home directorty then open invisible shell script with some text editor, ~/.bash_profile (macOS) or ~/.bashrc (linux) go to the bottom, you would see something like this,

export LD_LIBRARY_PATH = /usr/local/lib

change this like that( remove blank point around the = ),

export LD_LIBRARY_PATH=/usr/local/lib

it should be useful.

Flutter: how to make a TextField with HintText but no Underline?

Here is a supplemental answer that shows some fuller code:

enter image description here

  Container(
    decoration: BoxDecoration(
      color: Colors.tealAccent,
      borderRadius:  BorderRadius.circular(32),
    ),
    child: TextField(
      decoration: InputDecoration(
        hintStyle: TextStyle(fontSize: 17),
        hintText: 'Search your trips',
        suffixIcon: Icon(Icons.search),
        border: InputBorder.none,
        contentPadding: EdgeInsets.all(20),
      ),
    ),
  ),

Notes:

  • The dark background (code not shown) is Colors.teal.
  • InputDecoration also has a filled and fillColor property, but I couldn't get them to have a corner radius, so I used a container instead.

Eclipse, regular expression search and replace

For someone who needs an explanation and an example of how to use a regxp in Eclipse. Here is my example illustrating the problem.

enter image description here

I want to rename

/download.mp4^lecture_id=271

to

/271.mp4

And there can be multiple of these.

Here is how it should be done.

enter image description here

Then hit find/replace button

Communication between multiple docker-compose projects

The previous posts information is correct, but it does not have details on how to link containers, which should be connected as "external_links".

Hope this example make more clear to you:

  • Suppose you have app1/docker-compose.yml, with two services (svc11 and svc12), and app2/docker-compose.yml with two more services (svc21 and svc22) and suppose you need to connect in a crossed fashion:

  • svc11 needs to connect to svc22's container

  • svc21 needs to connect to svc11's container.

So the configuration should be like this:

this is app1/docker-compose.yml:


version: '2'
services:
    svc11:
        container_name: container11
        [..]
        networks:
            - default # this network
            - app2_default # external network
        external_links:
            - container22:container22
        [..]
    svc12:
       container_name: container12
       [..]

networks:
    default: # this network (app1)
        driver: bridge
    app2_default: # external network (app2)
        external: true

this is app2/docker-compose.yml:


version: '2'
services:
    svc21:
        container_name: container21
        [..]
        networks:
            - default # this network (app2)
            - app1_default # external network (app1)
        external_links:
            - container11:container11
        [..]
    svc22:
       container_name: container22
       [..]

networks:
    default: # this network (app2)
        driver: bridge
    app1_default: # external network (app1)
        external: true

RecyclerView onClick

In kotlin with constructor implementation

Initialize your Recyclerview constructor like below

class ListAdapter(
c: Context,
private var list: List<Project>,
private val itemClick: (Project) -> Unit
) : RecyclerView.Adapter<ListAdapter.ViewHolder>() 

return with itemClick in your onCreateViewHolder

override fun onCreateViewHolder(parent: ViewGroup, viewType: Int):ProjectViewHolder {
    val view = inflater.inflate(R.layout.list_item, parent, false)
    return ViewHolder(view, itemClick)
}

Your onBindViewHolder

override fun onBindViewHolder(holder: ViewHolder, position: Int) {
    holder.bindProject(list[position])
}

Then with viewHolder class create bindProject function.

class ViewHolder(
    view: View,
    private val itemClick: (Project) -> Unit
) : RecyclerView.ViewHolder(view) {

    private val clientTextCount = 7

    val titleTextView: TextView = view.projectTitleTextView

    fun bindProject(project: Project) {
        with(project) {
            titleTextView.text = name
            itemView.setOnClickListener { itemClick(this) }
        }
    }
}

Finally in your activity initialize adapter with lazy

private val adapter: ListAdapter by lazy {
    ListAdapter(this, projectList, {
        // Here you can implement your onClick function.
    })
}

For adding new list to recyclerview initialize below method in your adapter

fun setProjects(projects: List<Project>) {
        projectList = projects
        notifyDataSetChanged()
    }

and call setProjects method anywhere in your activity.

adapter.setProjects(projects)

That's it.

How to debug Javascript with IE 8

I discovered today that we can now debug Javascript With the developer tool bar plugins integreted in IE 8.

  • Click ? Tools on the toolbar, to the right of the tabs.
  • Select Developer Tools. The Developer Tools dialogue should open.
  • Click the Script tab in the dialogue.
  • Click the Start Debugging button.

You can use watch, breakpoint, see the call stack etc, similarly to debuggers in professional browsers.

You can also use the statement debugger; in your JavaScript code the set a breakpoint.

Showing the stack trace from a running Python application

python -dv yourscript.py

That will make the interpreter to run in debug mode and to give you a trace of what the interpreter is doing.

If you want to interactively debug the code you should run it like this:

python -m pdb yourscript.py

That tells the python interpreter to run your script with the module "pdb" which is the python debugger, if you run it like that the interpreter will be executed in interactive mode, much like GDB

Iterating through a variable length array

You've specifically mentioned a "variable-length array" in your question, so neither of the existing two answers (as I write this) are quite right.

Java doesn't have any concept of a "variable-length array", but it does have Collections, which serve in this capacity. Any collection (technically any "Iterable", a supertype of Collections) can be looped over as simply as this:

Collection<Thing> things = ...;
for (Thing t : things) {
  System.out.println(t);
}

EDIT: it's possible I misunderstood what he meant by 'variable-length'. He might have just meant it's a fixed length but not every instance is the same fixed length. In which case the existing answers would be fine. I'm not sure what was meant.

What's the difference between the Window.Loaded and Window.ContentRendered events

If you're using data binding, then you need to use the ContentRendered event.

For the code below, the Header is NULL when the Loaded event is raised. However, Header gets its value when the ContentRendered event is raised.

<MenuItem Header="{Binding NewGame_Name}" Command="{Binding NewGameCommand}" />

Stored Procedure error ORA-06550

Could you try this one:

create or replace 
procedure point_triangle
IS
BEGIN
  FOR thisteam in (select P.FIRSTNAME,P.LASTNAME, SUM(P.PTS) S from PLAYERREGULARSEASON P  where P.TEAM = 'IND'  group by P.FIRSTNAME, P.LASTNAME order by SUM(P.PTS) DESC)
  LOOP
    dbms_output.put_line(thisteam.FIRSTNAME|| ' ' || thisteam.LASTNAME  || ':' || thisteam.S);
  END LOOP;

END;

Return array in a function

Actually when you pass an array inside a function, the pointer to the original array is passed in the function parameter and thus the changes made to the array inside that function is actually made on the original array.

#include <iostream>

using namespace std;

int* func(int ar[])
{
    for(int i=0;i<100;i++) 
        ar[i]=i;
    int *ptr=ar;
    return ptr;
}


int main() {
    int *p;
    int y[100]={0};    
    p=func(y);

    for(int i=0;i<100;i++) 
        cout<<i<<" : "<<y[i]<<'\n';
}

Run it and you will see the changes

CMD command to check connected USB devices

you can download USBview and get all the information you need. Along with the list of devices it will also show you the configuration of each device.

avrdude: stk500v2_ReceiveMessage(): timeout

This isn't really a fixing solution but it may help others. Unlike Nick had said for me it was due to code in my program. I have the mega ADK model. The issue was tied to a switch statement for processing and parsing the returned byte[] from the usb connection to the Android. Its very strange because it would compile perfectly every time but would fail as the OP had stated. I commented it out and it worked fine.

How do I resolve a TesseractNotFoundError?

Most likely you have different versions of Python installed, ensure that the installed Tesseract is on the same Python version.

which pip3 shows you the path to the pip3 installation and which python3 shows the corresponding path to the Python installation.

Ensure that these two are the same.

How can I check what version/edition of Visual Studio is installed programmatically?

Put this code somewhere in your C++ project:

#ifdef _DEBUG
TCHAR version[50];
sprintf(&version[0], "Version = %d", _MSC_VER);
MessageBox(NULL, (LPCTSTR)szMsg, "Visual Studio", MB_OK | MB_ICONINFORMATION);
#endif

Note that _MSC_VER symbol is Microsoft specific. Here you can find a list of Visual Studio versions with the value for _MSC_VER for each version.

Getting number of days in a month

Use System.DateTime.DaysInMonth, from code sample:

const int July = 7;
const int Feb = 2;

// daysInJuly gets 31.
int daysInJuly = System.DateTime.DaysInMonth(2001, July);

// daysInFeb gets 28 because the year 1998 was not a leap year.
int daysInFeb = System.DateTime.DaysInMonth(1998, Feb);

// daysInFebLeap gets 29 because the year 1996 was a leap year.
int daysInFebLeap = System.DateTime.DaysInMonth(1996, Feb);

How to create a WPF Window without a border that can be resized via a grip only?

While the accepted answer is very true, just want to point out that AllowTransparency has some downfalls. It does not allow child window controls to show up, ie WebBrowser, and it usually forces software rendering which can have negative performance effects.

There is a better work around though.

When you want to create a window with no border that is resizeable and is able to host a WebBrowser control or a Frame control pointed to a URL you simply couldn't, the contents of said control would show empty.

I found a workaround though; in the Window, if you set the WindowStyle to None, ResizeMode to NoResize (bear with me, you will still be able to resize once done) then make sure you have UNCHECKED AllowsTransparency you will have a static sized window with no border and will show the browser control.

Now, you probably still want to be able to resize right? Well we can to that with a interop call:

    [DllImport("user32.dll", CharSet = CharSet.Auto)]
    private static extern IntPtr SendMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

    [DllImportAttribute("user32.dll")]
    public static extern bool ReleaseCapture();

    //Attach this to the MouseDown event of your drag control to move the window in place of the title bar
    private void WindowDrag(object sender, MouseButtonEventArgs e) // MouseDown
    {
        ReleaseCapture();
        SendMessage(new WindowInteropHelper(this).Handle,
            0xA1, (IntPtr)0x2, (IntPtr)0);
    }

    //Attach this to the PreviewMousLeftButtonDown event of the grip control in the lower right corner of the form to resize the window
    private void WindowResize(object sender, MouseButtonEventArgs e) //PreviewMousLeftButtonDown
    {
        HwndSource hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource;
        SendMessage(hwndSource.Handle, 0x112, (IntPtr)61448, IntPtr.Zero);
    }

And voila, A WPF window with no border and still movable and resizable without losing compatibility with with controls like WebBrowser

Adjust table column width to content size

The problem was the table width. I had used width: 100% for the table. The table columns are adjusted automatically after removing the width tag.

How do I left align these Bootstrap form items?

"pull-left" is what you need, it looks like you are using Bootstrap 2, I am not sure if that is available, consider bootstrap 3, unless ofcourse it is a huge rework! ... for Bootstrap 3 but you need to make sure you have 12 columns in each row as well, otherwise you will have issues.

How to show git log history (i.e., all the related commits) for a sub directory of a git repo?

For tracking changes to a folder where the folder was moved, I started using:

git rev-list --all --pretty=oneline -- "*/foo/subfoo/*"

This isn't perfect as it will grab other folders with the same name, but if it is unique, then it seems to work.

Not able to start Genymotion device

In my case, I restart the computer and enable the virtualization technology in BIOS. Then start up computer, open VM Virtual Box, choose a virtual device, go to Settings-General-Basic-Version, choose ubuntu(64 bit), save the settings then start virtual device from genymotion, everything is ok now.

Change New Google Recaptcha (v2) Width

This is my work around:

1) Add a wrapper div to the recaptcha div.

<div id="recaptcha-wrapper"><div class="g-recaptcha" data-sitekey="..."></div></div>

2) Add javascript/jquery code.

$(function(){
    // global variables
    captchaResized = false;
    captchaWidth = 304;
    captchaHeight = 78;
    captchaWrapper = $('#recaptcha-wrapper');
    captchaElements = $('#rc-imageselect, .g-recaptcha');

    resizeCaptcha();
    $(window).on('resize', function() {
        resizeCaptcha();
    });
});

function resizeCaptcha() {
    if (captchaWrapper.width() >= captchaWidth) {
        if (captchaResized) {
            captchaElements.css('transform', '').css('-webkit-transform', '').css('-ms-transform', '').css('-o-transform', '').css('transform-origin', '').css('-webkit-transform-origin', '').css('-ms-transform-origin', '').css('-o-transform-origin', '');
            captchaWrapper.height(captchaHeight);
            captchaResized = false;
        }
    } else {
        var scale = (1 - (captchaWidth - captchaWrapper.width()) * (0.05/15));
        captchaElements.css('transform', 'scale('+scale+')').css('-webkit-transform', 'scale('+scale+')').css('-ms-transform', 'scale('+scale+')').css('-o-transform', 'scale('+scale+')').css('transform-origin', '0 0').css('-webkit-transform-origin', '0 0').css('-ms-transform-origin', '0 0').css('-o-transform-origin', '0 0');
        captchaWrapper.height(captchaHeight * scale);
        if (captchaResized == false) captchaResized = true;
    }
}

3) Optional: add some styling if needed.

#recaptcha-wrapper { text-align:center; margin-bottom:15px; }

.g-recaptcha { display:inline-block; }

On a CSS hover event, can I change another div's styling?

The following example is based on jQuery but it can be achieved using any JS tool kit or even plain old JS

$(document).ready(function(){
     $("#a").mouseover(function(){
         $("#b").css("background-color", "red");
     });
});

How to check if C string is empty

Since C-style strings are always terminated with the null character (\0), you can check whether the string is empty by writing

do {
   ...
} while (url[0] != '\0');

Alternatively, you could use the strcmp function, which is overkill but might be easier to read:

do {
   ...
} while (strcmp(url, ""));

Note that strcmp returns a nonzero value if the strings are different and 0 if they're the same, so this loop continues to loop until the string is nonempty.

Hope this helps!

How to install wget in macOS?

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

And then install wget with brew and also enable openressl for TLS support

brew install wget --with-libressl

It worked perfectly for me.

Select data from date range between two dates

this is easy, use this query to find what you want.

select * from Product_Sales where From_date<='2018-04-11' and To_date>='2018-04-11'

Class method differences in Python: bound, unbound and static

The definition of method_two is invalid. When you call method_two, you'll get TypeError: method_two() takes 0 positional arguments but 1 was given from the interpreter.

An instance method is a bounded function when you call it like a_test.method_two(). It automatically accepts self, which points to an instance of Test, as its first parameter. Through the self parameter, an instance method can freely access attributes and modify them on the same object.

Laravel 5 – Remove Public from URL

I have read some article before and it's working fine but really don't know is safe or not

    a. Create new folder local.
    b. Move all project into the local folder expect public folder.
    c. Move all the content of public folder to project root.
    d. Delete the blank public folder
    f. Edit the index file. 

Edit the index.php

require __DIR__.'/../bootstrap/autoload.php';
$app = require_once __DIR__.'/../bootstrap/app.php';

to

require __DIR__.'/local/bootstrap/autoload.php';
$app = require_once __DIR__.'/local/bootstrap/app.php';

I can't install python-ldap

sudo apt-get install build-essential python3-dev python2.7-dev libldap2-dev libsasl2-dev slapd ldap-utils python-tox lcov valgrind

Convert SVG to image (JPEG, PNG, etc.) in the browser

This seems to work in most browsers:

function copyStylesInline(destinationNode, sourceNode) {
   var containerElements = ["svg","g"];
   for (var cd = 0; cd < destinationNode.childNodes.length; cd++) {
       var child = destinationNode.childNodes[cd];
       if (containerElements.indexOf(child.tagName) != -1) {
            copyStylesInline(child, sourceNode.childNodes[cd]);
            continue;
       }
       var style = sourceNode.childNodes[cd].currentStyle || window.getComputedStyle(sourceNode.childNodes[cd]);
       if (style == "undefined" || style == null) continue;
       for (var st = 0; st < style.length; st++){
            child.style.setProperty(style[st], style.getPropertyValue(style[st]));
       }
   }
}

function triggerDownload (imgURI, fileName) {
  var evt = new MouseEvent("click", {
    view: window,
    bubbles: false,
    cancelable: true
  });
  var a = document.createElement("a");
  a.setAttribute("download", fileName);
  a.setAttribute("href", imgURI);
  a.setAttribute("target", '_blank');
  a.dispatchEvent(evt);
}

function downloadSvg(svg, fileName) {
  var copy = svg.cloneNode(true);
  copyStylesInline(copy, svg);
  var canvas = document.createElement("canvas");
  var bbox = svg.getBBox();
  canvas.width = bbox.width;
  canvas.height = bbox.height;
  var ctx = canvas.getContext("2d");
  ctx.clearRect(0, 0, bbox.width, bbox.height);
  var data = (new XMLSerializer()).serializeToString(copy);
  var DOMURL = window.URL || window.webkitURL || window;
  var img = new Image();
  var svgBlob = new Blob([data], {type: "image/svg+xml;charset=utf-8"});
  var url = DOMURL.createObjectURL(svgBlob);
  img.onload = function () {
    ctx.drawImage(img, 0, 0);
    DOMURL.revokeObjectURL(url);
    if (typeof navigator !== "undefined" && navigator.msSaveOrOpenBlob)
    {
        var blob = canvas.msToBlob();         
        navigator.msSaveOrOpenBlob(blob, fileName);
    } 
    else {
        var imgURI = canvas
            .toDataURL("image/png")
            .replace("image/png", "image/octet-stream");
        triggerDownload(imgURI, fileName);
    }
    document.removeChild(canvas);
  };
  img.src = url;
}