Programs & Examples On #Convex optimization

Convex minimization, a subfield of optimization, studies the problem of minimizing convex functions over convex sets. The convexity property can make optimization in some sense "easier" than the general case - for example, any local minimum must be a global minimum.

Add colorbar to existing axis

Couldn't add this as a comment, but in case anyone is interested in using the accepted answer with subplots, the divider should be formed on specific axes object (rather than on the numpy.ndarray returned from plt.subplots)

import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import make_axes_locatable
data = np.arange(100, 0, -1).reshape(10, 10)
fig, ax = plt.subplots(ncols=2, nrows=2)
for row in ax:
    for col in row:
        im = col.imshow(data, cmap='bone')
        divider = make_axes_locatable(col)
        cax = divider.append_axes('right', size='5%', pad=0.05)
        fig.colorbar(im, cax=cax, orientation='vertical')
plt.show()

How to change the background color on a input checkbox with css?

I always use pseudo elements :before and :after for changing the appearance of checkboxes and radio buttons. it's works like a charm.

Refer this link for more info

CODEPEN

Steps

  1. Hide the default checkbox using css rules like visibility:hidden or opacity:0 or position:absolute;left:-9999px etc.
  2. Create a fake checkbox using :before element and pass either an empty or a non-breaking space '\00a0';
  3. When the checkbox is in :checked state, pass the unicode content: "\2713", which is a checkmark;
  4. Add :focus style to make the checkbox accessible.
  5. Done

Here is how I did it.

_x000D_
_x000D_
.box {_x000D_
  background: #666666;_x000D_
  color: #ffffff;_x000D_
  width: 250px;_x000D_
  padding: 10px;_x000D_
  margin: 1em auto;_x000D_
}_x000D_
p {_x000D_
  margin: 1.5em 0;_x000D_
  padding: 0;_x000D_
}_x000D_
input[type="checkbox"] {_x000D_
  visibility: hidden;_x000D_
}_x000D_
label {_x000D_
  cursor: pointer;_x000D_
}_x000D_
input[type="checkbox"] + label:before {_x000D_
  border: 1px solid #333;_x000D_
  content: "\00a0";_x000D_
  display: inline-block;_x000D_
  font: 16px/1em sans-serif;_x000D_
  height: 16px;_x000D_
  margin: 0 .25em 0 0;_x000D_
  padding: 0;_x000D_
  vertical-align: top;_x000D_
  width: 16px;_x000D_
}_x000D_
input[type="checkbox"]:checked + label:before {_x000D_
  background: #fff;_x000D_
  color: #333;_x000D_
  content: "\2713";_x000D_
  text-align: center;_x000D_
}_x000D_
input[type="checkbox"]:checked + label:after {_x000D_
  font-weight: bold;_x000D_
}_x000D_
_x000D_
input[type="checkbox"]:focus + label::before {_x000D_
    outline: rgb(59, 153, 252) auto 5px;_x000D_
}
_x000D_
<div class="content">_x000D_
  <div class="box">_x000D_
    <p>_x000D_
      <input type="checkbox" id="c1" name="cb">_x000D_
      <label for="c1">Option 01</label>_x000D_
    </p>_x000D_
    <p>_x000D_
      <input type="checkbox" id="c2" name="cb">_x000D_
      <label for="c2">Option 02</label>_x000D_
    </p>_x000D_
    <p>_x000D_
      <input type="checkbox" id="c3" name="cb">_x000D_
      <label for="c3">Option 03</label>_x000D_
    </p>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Much more stylish using :before and :after

_x000D_
_x000D_
body{_x000D_
  font-family: sans-serif;  _x000D_
}_x000D_
_x000D_
.container {_x000D_
    margin-top: 50px;_x000D_
    margin-left: 20px;_x000D_
    margin-right: 20px;_x000D_
}_x000D_
.checkbox {_x000D_
    width: 100%;_x000D_
    margin: 15px auto;_x000D_
    position: relative;_x000D_
    display: block;_x000D_
}_x000D_
_x000D_
.checkbox input[type="checkbox"] {_x000D_
    width: auto;_x000D_
    opacity: 0.00000001;_x000D_
    position: absolute;_x000D_
    left: 0;_x000D_
    margin-left: -20px;_x000D_
}_x000D_
.checkbox label {_x000D_
    position: relative;_x000D_
}_x000D_
.checkbox label:before {_x000D_
    content: '';_x000D_
    position: absolute;_x000D_
    left: 0;_x000D_
    top: 0;_x000D_
    margin: 4px;_x000D_
    width: 22px;_x000D_
    height: 22px;_x000D_
    transition: transform 0.28s ease;_x000D_
    border-radius: 3px;_x000D_
    border: 2px solid #7bbe72;_x000D_
}_x000D_
.checkbox label:after {_x000D_
  content: '';_x000D_
    display: block;_x000D_
    width: 10px;_x000D_
    height: 5px;_x000D_
    border-bottom: 2px solid #7bbe72;_x000D_
    border-left: 2px solid #7bbe72;_x000D_
    -webkit-transform: rotate(-45deg) scale(0);_x000D_
    transform: rotate(-45deg) scale(0);_x000D_
    transition: transform ease 0.25s;_x000D_
    will-change: transform;_x000D_
    position: absolute;_x000D_
    top: 12px;_x000D_
    left: 10px;_x000D_
}_x000D_
.checkbox input[type="checkbox"]:checked ~ label::before {_x000D_
    color: #7bbe72;_x000D_
}_x000D_
_x000D_
.checkbox input[type="checkbox"]:checked ~ label::after {_x000D_
    -webkit-transform: rotate(-45deg) scale(1);_x000D_
    transform: rotate(-45deg) scale(1);_x000D_
}_x000D_
_x000D_
.checkbox label {_x000D_
    min-height: 34px;_x000D_
    display: block;_x000D_
    padding-left: 40px;_x000D_
    margin-bottom: 0;_x000D_
    font-weight: normal;_x000D_
    cursor: pointer;_x000D_
    vertical-align: sub;_x000D_
}_x000D_
.checkbox label span {_x000D_
    position: absolute;_x000D_
    top: 50%;_x000D_
    -webkit-transform: translateY(-50%);_x000D_
    transform: translateY(-50%);_x000D_
}_x000D_
.checkbox input[type="checkbox"]:focus + label::before {_x000D_
    outline: 0;_x000D_
}
_x000D_
<div class="container"> _x000D_
  <div class="checkbox">_x000D_
     <input type="checkbox" id="checkbox" name="" value="">_x000D_
     <label for="checkbox"><span>Checkbox</span></label>_x000D_
  </div>_x000D_
_x000D_
  <div class="checkbox">_x000D_
     <input type="checkbox" id="checkbox2" name="" value="">_x000D_
     <label for="checkbox2"><span>Checkbox</span></label>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to start debug mode from command prompt for apache tomcat server?

On windows
$ catalina.bat jpda start
On Linux/Unix
$ catalina.sh jpda start

More info ----> https://cwiki.apache.org/confluence/display/TOMCAT/Developing

How to write subquery inside the OUTER JOIN Statement

You need the "correlation id" (the "AS SS" thingy) on the sub-select to reference the fields in the "ON" condition. The id's assigned inside the sub select are not usable in the join.

SELECT
       cs.CUSID
       ,dp.DEPID
FROM
    CUSTMR cs
        LEFT OUTER JOIN (
            SELECT
                    DEPID
                    ,DEPNAME
                FROM
                    DEPRMNT 
                WHERE
                    dp.DEPADDRESS = 'TOKYO'
        ) ss
            ON (
                ss.DEPID = cs.CUSID
                AND ss.DEPNAME = cs.CUSTNAME
            )
WHERE
    cs.CUSID != '' 

WindowsError: [Error 126] The specified module could not be found

I met the same problem in Win10 32bit OS. I resolved the problem by changing the DLL from debug to release version.

I think it is because the debug version DLL depends on other DLL, and the release version did not.

Setting a log file name to include current date in Log4j

I'm 99% sure that RollingFileAppender/DailyRollingFileAppender, while it gives you the date-rolling functionality you want, doesn't have any way to specify that the current log file should use the DatePattern as well.

You might just be able to simply subclass RollingFileAppender (or DailyRollingFileAppender, I forget which is which in log4net) and modify the naming logic.

How to get cell value from DataGridView in VB.Net?

It is working for me

MsgBox(DataGridView1.CurrentRow.Cells(0).Value.ToString)

enter image description here

Set and Get Methods in java?

I want to add to other answers that setters can be used to prevent putting the object in an invalid state.

For instance let's suppose that I've to set a TaxId, modelled as a String. The first version of the setter can be as follows:

private String taxId;

public void setTaxId(String taxId) {
    this.taxId = taxId;
}

However we'd better prevent the use to set the object with an invalid taxId, so we can introduce a check:

private String taxId;

public void setTaxId(String taxId) throws IllegalArgumentException {
    if (isTaxIdValid(taxId)) {
        throw new IllegalArgumentException("Tax Id '" + taxId + "' is invalid");
    }
    this.taxId = taxId;
}

The next step, to improve the modularity of the program, is to make the TaxId itself as an Object, able to check itself.

private final TaxId taxId = new TaxId()

public void setTaxId(String taxIdString) throws IllegalArgumentException {
    taxId.set(taxIdString); //will throw exception if not valid
}

Similarly for the getter, what if we don't have a value yet? Maybe we want to have a different path, we could say:

public String getTaxId() throws IllegalStateException {
    return taxId.get(); //will throw exception if not set
}

How do I stretch an image to fit the whole background (100% height x 100% width) in Flutter?

Inside your Stack, you should wrap your background widget in a Positioned.fill.

return new Stack(
  children: <Widget>[
    new Positioned.fill(
      child: background,
    ),
    foreground,
  ],
);

How to restart ADB manually from Android Studio

When I had this problem, I wrote adb kill-server and adb restart-server in terminal, but the problem appeared again the next day. Then I updated GPU debugging tools in the Android SDK manager and restarted the computer, which worked for me.

Mongoimport of json file

In windows you can use your Command Prompcmd cmd , in Ubuntu you can use your terminal by typing the following command:

mongoimport  -d  your_database_name  -c  your_collection_name  /path_to_json_file/json_file_name.json

then when you open your mongo shell, you will find to check your database_name when running this command:

show databases

How do I push a local Git branch to master branch in the remote?

You can also do it this way to reference the previous branch implicitly:

git checkout mainline
git pull
git merge -
git push

Using only CSS, show div on hover over <a>

From my testing using this CSS:

.expandable{
display: none;
}
.expand:hover+.expandable{
display:inline !important;
}
.expandable:hover{
display:inline !important;
}

And this HTML:

<div class="expand">expand</div>
<div class="expand">expand</div>
<div class="expandable">expandable</div>

, it resulted that it does expand using the second , but does not expand using the first one. So if there is a div between the hover target and the hidden div, then it will not work.

JQuery Ajax Post results in 500 Internal Server Error

Your code contains dataType: json.

In this case jQuery evaluates the response as JSON and returns a JavaScript object. The JSON data is parsed in a strict manner. Any malformed JSON is rejected and a parse error is thrown. An empty response is also rejected.

The server should return a response of null or {} instead.

How do I get the color from a hexadecimal color code using .NET?

You can see Silverlight/WPF sets ellipse with hexadecimal colour for using a hex value:

your_contorl.Color = DirectCast(ColorConverter.ConvertFromString("#D8E0A627"), Color)

Find non-ASCII characters in varchar columns using SQL Server

This script searches for non-ascii characters in one column. It generates a string of all valid characters, here code point 32 to 127. Then it searches for rows that don't match the list:

declare @str varchar(128)
declare @i int
set @str = ''
set @i = 32
while @i <= 127
    begin
    set @str = @str + '|' + char(@i)
    set @i = @i + 1
    end

select  col1
from    YourTable
where   col1 like '%[^' + @str + ']%' escape '|'

How do I pass a command line argument while starting up GDB in Linux?

I'm using GDB7.1.1, as --help shows:

gdb [options] --args executable-file [inferior-arguments ...]

IMHO, the order is a bit unintuitive at first.

how to delete all cookies of my website in php

PHP setcookie()

Taken from that page, this will unset all of the cookies for your domain:

// unset cookies
if (isset($_SERVER['HTTP_COOKIE'])) {
    $cookies = explode(';', $_SERVER['HTTP_COOKIE']);
    foreach($cookies as $cookie) {
        $parts = explode('=', $cookie);
        $name = trim($parts[0]);
        setcookie($name, '', time()-1000);
        setcookie($name, '', time()-1000, '/');
    }
}

http://www.php.net/manual/en/function.setcookie.php#73484

Setting environment variables in Linux using Bash

The reason people often suggest writing

VAR=value
export VAR

instead of the shorter

export VAR=value

is that the longer form works in more different shells than the short form. If you know you're dealing with bash, either works fine, of course.

Difference between del, remove, and pop on lists

Since no-one else has mentioned it, note that del (unlike pop) allows the removal of a range of indexes because of list slicing:

>>> lst = [3, 2, 2, 1]
>>> del lst[1:]
>>> lst
[3]

This also allows avoidance of an IndexError if the index is not in the list:

>>> lst = [3, 2, 2, 1]
>>> del lst[10:]
>>> lst
[3, 2, 2, 1]

InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately

The docs give a fair indicator of what's required., however requests allow us to skip a few steps:

You only need to install the security package extras (thanks @admdrew for pointing it out)

$ pip install requests[security]

or, install them directly:

$ pip install pyopenssl ndg-httpsclient pyasn1

Requests will then automatically inject pyopenssl into urllib3


If you're on ubuntu, you may run into trouble installing pyopenssl, you'll need these dependencies:

$ apt-get install libffi-dev libssl-dev

Creating a "logical exclusive or" operator in Java

Java does have a logical XOR operator, it is ^ (as in a ^ b).

Apart from that, you can't define new operators in Java.

Edit: Here's an example:

public static void main(String[] args) {
    boolean[] all = { false, true };
    for (boolean a : all) {
        for (boolean b: all) {
            boolean c = a ^ b;
            System.out.println(a + " ^ " + b + " = " + c);
        }
    }
}

Output:

false ^ false = false
false ^ true = true
true ^ false = true
true ^ true = false

iPhone SDK on Windows (alternative solutions)

There is another solution if you want to develop in C/C++. http://www.DragonFireSDK.com will allow you to build iPhone applications in Visual Studio on Windows. It's worth a look-see for sure.

Redirect all output to file using Bash on Linux?

Though not POSIX, bash 4 has the &> operator:

command &> alloutput.txt

Multiple GitHub Accounts & SSH Config

As a complement of @stefano 's answer, It is better to use command with -f when generate a new SSH key for another account,

ssh-keygen -t rsa -f ~/.ssh/id_rsa_work -C "[email protected]"

Since id_rsa_work file doesn't exist in path ~/.ssh/, and I create this file manually, and it doesn't work :(

putting a php variable in a HTML form value

You can do it like this,

<input type="text" name="name" value="<?php echo $name;?>" />

But seen as you've taken it straight from user input, you want to sanitize it first so that nothing nasty is put into the output of your page.

<input type="text" name="name" value="<?php echo htmlspecialchars($name);?>" />

What MySQL data type should be used for Latitude/Longitude with 8 decimal places?

Additionally, you will see that float values are rounded.

// e.g: given values 41.0473112,29.0077011

float(11,7) | decimal(11,7)
---------------------------
41.0473099  | 41.0473112
29.0077019  | 29.0077011

what is the multicast doing on 224.0.0.251?

Those look much like Bonjour / mDNS requests to me. Those packets use multicast IP address 224.0.0.251 and port 5353.

The most likely source for this is Apple iTunes, which comes pre-installed on Mac computers (and is a popular install on Windows machines as well). Apple iTunes uses it to discover other iTunes-compatible devices in the same WiFi network.

mDNS is also used (primarily by Apple's Mac and iOS devices) to discover mDNS-compatible devices such as printers on the same network.

If this is a Linux box instead, it's probably the Avahi daemon then. Avahi is ZeroConf/Bonjour compatible and installed by default, but if you don't use DNS-SD or mDNS, it can be disabled.

How to use conditional breakpoint in Eclipse?

A way that might be more convenient: where you want a breakpoint, write a no-op if statement and set a breakpoint in its contents.

if(tablist[i].equalsIgnoreCase("LEADDELEGATES")) {
-->    int noop = 0; //don't do anything
}

(the breakpoint is represented by the arrow)

This way, the breakpoint only triggers if your condition is true. This could potentially be easier without that many pop-ups.

React Hooks useState() with Object

If anyone is searching for useState() hooks update for object

- Through Input

        const [state, setState] = useState({ fName: "", lName: "" });
        const handleChange = e => {
            const { name, value } = e.target;
            setState(prevState => ({
                ...prevState,
                [name]: value
            }));
        };

        <input
            value={state.fName}
            type="text"
            onChange={handleChange}
            name="fName"
        />
        <input
            value={state.lName}
            type="text"
            onChange={handleChange}
            name="lName"
        />
   ***************************

 - Through onSubmit or button click
    
        setState(prevState => ({
            ...prevState,
            fName: 'your updated value here'
         }));

Best way to store data locally in .NET (C#)

It really depends on what you're storing. If you're talking about structured data, then either XML or a very lightweight SQL RDBMS like SQLite or SQL Server Compact Edition will work well for you. The SQL solution becomes especially compelling if the data moves beyond a trivial size.

If you're storing large pieces of relatively unstructured data (binary objects like images, for example) then obviously neither a database nor XML solution are appropriate, but given your question I'm guessing it's more of the former than the latter.

How to open .dll files to see what is written inside?

Telerik's Just Decompile is the best I've used. It's free once you sign up with an email.

enter link description here

What is the cause for "angular is not defined"

You have not placed the script tags for angular js

you can do so by using cdn or downloading the angularjs for your project and then referencing it

after this you have to add your own java script in your case main.js

that should do

Git merge errors

Change branch, discarding all local modifications

git checkout -f 9-sign-in-out 

Rename the current branch to master, discarding current master

git branch -M master 

Installing Java 7 on Ubuntu

Oracle Java 1.7.0 from .deb packages

wget https://raw.github.com/flexiondotorg/oab-java6/master/oab-java.sh
chmod +x oab-java.sh
sudo ./oab-java.sh -7
sudo apt-get update
sudo sudo apt-get install oracle-java7-jdk oracle-java7-fonts oracle-java7-source 
sudo apt-get dist-upgrade

Workaround for 1.7.0_51

There is an Issue 123 currently in OAB and a pull request

Here is the patched vesion:

wget https://raw.github.com/ladios/oab-java6/master/oab-java.sh
chmod +x oab-java.sh
sudo ./oab-java.sh -7
sudo apt-get update
sudo sudo apt-get install oracle-java7-jdk oracle-java7-fonts oracle-java7-source 
sudo apt-get dist-upgrade

Write HTML string in JSON

One way is to replace the double quotes in the HTML with single quotes but using double quotes has become the standard convention for attribute values in HTML.

The better option is to escape the double quotes in json and other characters that need to be escaped.

You can get some more details about escaping here: Where can I find a list of escape characters required for my JSON ajax return type?

How to "z-index" to make a menu always on top of the content

Ok, Im assuming you want to put the .left inside the container so I suggest you edit your html. The key is the position:absolute and right:0

#right { 
    background-color: red;
    height: 300px;
    width: 300px;
    z-index: 999999;
    margin-top: 0px;
    position: absolute;
    right:0;
}

here is the full code: http://jsfiddle.net/T9FJL/

setImmediate vs. nextTick

Use setImmediate if you want to queue the function behind whatever I/O event callbacks that are already in the event queue. Use process.nextTick to effectively queue the function at the head of the event queue so that it executes immediately after the current function completes.

So in a case where you're trying to break up a long running, CPU-bound job using recursion, you would now want to use setImmediate rather than process.nextTick to queue the next iteration as otherwise any I/O event callbacks wouldn't get the chance to run between iterations.

How should I throw a divide by zero exception in Java without actually dividing by zero?

Something like:

if(divisor == 0) {
  throw new ArithmeticException("Division by zero!");
}

Constructors in JavaScript objects

http://www.jsoops.net/ is quite good for oop in Js. If provide private, protected, public variable and function, and also Inheritance feature. Example Code:

var ClassA = JsOops(function (pri, pro, pub)
{// pri = private, pro = protected, pub = public

    pri.className = "I am A ";

    this.init = function (var1)// constructor
    {
        pri.className += var1;
    }

    pub.getData = function ()
    {
        return "ClassA(Top=" + pro.getClassName() + ", This=" + pri.getClassName()
        + ", ID=" + pro.getClassId() + ")";
    }

    pri.getClassName = function () { return pri.className; }
    pro.getClassName = function () { return pri.className; }
    pro.getClassId = function () { return 1; }
});

var newA = new ClassA("Class");

//***Access public function
console.log(typeof (newA.getData));
// function
console.log(newA.getData());
// ClassA(Top=I am A Class, This=I am A Class, ID=1)

//***You can not access constructor, private and protected function
console.log(typeof (newA.init));            // undefined
console.log(typeof (newA.className));       // undefined
console.log(typeof (newA.pro));             // undefined
console.log(typeof (newA.getClassName));    // undefined

correct PHP headers for pdf file download

I had the same problem recently and this helped me:

    header('Content-Description: File Transfer'); 
    header('Content-Type: application/octet-stream'); 
    header('Content-Disposition: attachment; filename="FILENAME"'); 
    header('Content-Transfer-Encoding: binary'); 
    header('Expires: 0'); 
    header('Cache-Control: must-revalidate, post-check=0, pre-check=0'); 
    header('Pragma: public'); 
    header('Content-Length: ' . filesize("PATH/TO/FILE")); 
    ob_clean(); 
    flush(); 
    readfile(PATH/TO/FILE);      
    exit();

I found this answer here

Declaring variable workbook / Worksheet vba

Third solution: I would set ws to a sheet of workbook wb as the use of Sheet("name") always refers to the active workbook, which might change as your code develops.

sub kl() 

    Dim wb As Workbook
    Dim ws As Worksheet

    Set wb = ActiveWorkbook
    'be aware as this might produce an error, if Shet "name" does not exist
    Set ws = wb.Sheets("name")
    ' if wb is other than the active workbook
    wb.activate
    ws.Select

End Sub

"Failed to load platform plugin "xcb" " while launching qt5 app on linux without qt installed

I had this problem, and on a hunch I removed the Qt Configs from my environment. I.e.,

rm -rf ~/.config/Qt*

Then I started qtcreator and it reconfigured itself with the existing state of the machine. It no longer remembered where my projects were, but that just meant I had to browse to them "for the first time" again.

But more importantly it built itself a coherent set of library paths, so I could rebuild and run my project executables again without the xcb or qxcb libraries going missing.

HttpContext.Current.User.Identity.Name is Empty

I also had this problem recently. Working with a new client, trying to get a an old web forms app running from Visual Studio, with IISExpress using Windows Authentication. For me, the web.config was correctly configured

However, the IISExpress.config settings file had:

<windowsAuthentication enabled="false">

The user account the developer was logged in was very new, so unlikely it had been edited. Simple fix it turned out, change this to enabled=true and it all ran as it should then.

What is the best way to repeatedly execute a function every x seconds?

If your program doesn't have a event loop already, use the sched module, which implements a general purpose event scheduler.

import sched, time
s = sched.scheduler(time.time, time.sleep)
def do_something(sc): 
    print("Doing stuff...")
    # do your stuff
    s.enter(60, 1, do_something, (sc,))

s.enter(60, 1, do_something, (s,))
s.run()

If you're already using an event loop library like asyncio, trio, tkinter, PyQt5, gobject, kivy, and many others - just schedule the task using your existing event loop library's methods, instead.

How to auto-scroll to end of div when data is added?

var objDiv = document.getElementById("divExample");
objDiv.scrollTop = objDiv.scrollHeight;

How to go to a URL using jQuery?

window.location is just what you need. Other thing you can do is to create anchor element and simulate click on it

$("<a href='your url'></a>").click(); 

How do I remove my IntelliJ license in 2019.3?

in linux/ubuntu you can do, run following commands

cd ~/.config/JetBrains/PyCharm2020.1
rm eval/PyCharm201.evaluation.key
sed -i '/evlsprt/d' options/other.xml
cd ~/.java/.userPrefs/jetbrains
rm -rf pycharm*

How to add a right button to a UINavigationController?

This issue can occur if we delete the view controller or try to add new view controller inside the interface builder(main.storyboard). To fix this issue, it requires to add "Navigation Item" inside new view controller. Sometimes it happens that we create new view controller screen and it does not connect to "Navigation Item" automatically.

  1. Go to the main.storyboard.
  2. Select that new view Controller.
  3. Go to the document outline.
  4. Check view Controller contents.
  5. If new view controller does not have a Navigation item then, copy Navigation item from previous View Controller and paste it into the new view controller.
  6. save and clean the project.

line breaks in a textarea

What I found works in the form is str_replace('&lt;br&gt;', PHP_EOL, $textarea);

Printing without newline (print 'a',) prints a space, how to remove?

There are a number of ways of achieving your result. If you're just wanting a solution for your case, use string multiplication as @Ant mentions. This is only going to work if each of your print statements prints the same string. Note that it works for multiplication of any length string (e.g. 'foo' * 20 works).

>>> print 'a' * 20
aaaaaaaaaaaaaaaaaaaa

If you want to do this in general, build up a string and then print it once. This will consume a bit of memory for the string, but only make a single call to print. Note that string concatenation using += is now linear in the size of the string you're concatenating so this will be fast.

>>> for i in xrange(20):
...     s += 'a'
... 
>>> print s
aaaaaaaaaaaaaaaaaaaa

Or you can do it more directly using sys.stdout.write(), which print is a wrapper around. This will write only the raw string you give it, without any formatting. Note that no newline is printed even at the end of the 20 as.

>>> import sys
>>> for i in xrange(20):
...     sys.stdout.write('a')
... 
aaaaaaaaaaaaaaaaaaaa>>> 

Python 3 changes the print statement into a print() function, which allows you to set an end parameter. You can use it in >=2.6 by importing from __future__. I'd avoid this in any serious 2.x code though, as it will be a little confusing for those who have never used 3.x. However, it should give you a taste of some of the goodness 3.x brings.

>>> from __future__ import print_function
>>> for i in xrange(20):
...     print('a', end='')
... 
aaaaaaaaaaaaaaaaaaaa>>> 

How do I iterate over a JSON structure?

Taken from jQuery docs:

var arr = [ "one", "two", "three", "four", "five" ];
var obj = { one:1, two:2, three:3, four:4, five:5 };

jQuery.each(arr, function() {
  $("#" + this).text("My id is " + this + ".");
  return (this != "four"); // will stop running to skip "five"
});

jQuery.each(obj, function(i, val) {
  $("#" + i).append(document.createTextNode(" - " + val));
});

Should Jquery code go in header or footer?

Although almost all web sites still place Jquery and other javascript on header :D , even check stackoverflow.com .

I also suggest you to put on before end tag of body. You can check loading time after placing on either places. Script tag will pause your webpage to load further.

and after placing javascript on footer, you may get unusual looks of your webpage until it loads javascript, so place css on your header section.

Converting JSON to XML in Java

Use the (excellent) JSON-Java library from json.org then

JSONObject json = new JSONObject(str);
String xml = XML.toString(json);

toString can take a second argument to provide the name of the XML root node.

This library is also able to convert XML to JSON using XML.toJSONObject(java.lang.String string)

Check the Javadoc

Link to the the github repository

POM

<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20160212</version>
</dependency>

original post updated with new links

Convert a byte array to integer in Java and vice versa

Someone with a requirement where they have to read from bits, lets say you have to read from only 3 bits but you need signed integer then use following:

data is of type: java.util.BitSet

new BigInteger(data.toByteArray).intValue() << 32 - 3 >> 32 - 3

The magic number 3 can be replaced with the number of bits (not bytes) you are using.

MVC which submit button has been pressed

To make it easier I will say you can change your buttons to the following:

<input name="btnSubmit" type="submit" value="Save" />
<input name="btnProcess" type="submit" value="Process" />

Your controller:

public ActionResult Create(string btnSubmit, string btnProcess)
{
    if(btnSubmit != null)
       // do something for the Button btnSubmit
    else 
       // do something for the Button btnProcess
}

How to read specific lines from a file (by line number)?

If the file to read is big, and you don't want to read the whole file in memory at once:

fp = open("file")
for i, line in enumerate(fp):
    if i == 25:
        # 26th line
    elif i == 29:
        # 30th line
    elif i > 29:
        break
fp.close()

Note that i == n-1 for the nth line.


In Python 2.6 or later:

with open("file") as fp:
    for i, line in enumerate(fp):
        if i == 25:
            # 26th line
        elif i == 29:
            # 30th line
        elif i > 29:
            break

Get array of object's keys

Of course, Object.keys() is the best way to get an Object's keys. If it's not available in your environment, it can be trivially shimmed using code such as in your example (except you'd need to take into account your loop will iterate over all properties up the prototype chain, unlike Object.keys()'s behaviour).

However, your example code...

var foo = { 'alpha' : 'puffin', 'beta' : 'beagle' };
var keys = [];
for (var key in foo) {
    keys.push(key);
}

jsFiddle.

...could be modified. You can do the assignment right in the variable part.

var foo = { 'alpha' : 'puffin', 'beta' : 'beagle' };
var keys = [], i = 0;
for (keys[i++] in foo) {}

jsFiddle.

Of course, this behaviour is different to what Object.keys() actually does (jsFiddle). You could simply use the shim on the MDN documentation.

How to bind a List to a ComboBox?

As you are referring to a combobox, I'm assuming you don't want to use 2-way databinding (if so, look at using a BindingList)

public class Country
{
    public string Name { get; set; }
    public IList<City> Cities { get; set; }
    public Country(string _name)
    {
        Cities = new List<City>();
        Name = _name;
    }
}



List<Country> countries = new List<Country> { new Country("UK"), 
                                     new Country("Australia"), 
                                     new Country("France") };

var bindingSource1 = new BindingSource();
bindingSource1.DataSource = countries;

comboBox1.DataSource = bindingSource1.DataSource;

comboBox1.DisplayMember = "Name";
comboBox1.ValueMember = "Name";

To find the country selected in the bound combobox, you would do something like: Country country = (Country)comboBox1.SelectedItem;.

If you want the ComboBox to dynamically update you'll need to make sure that the data structure that you have set as the DataSource implements IBindingList; one such structure is BindingList<T>.


Tip: make sure that you are binding the DisplayMember to a Property on the class and not a public field. If you class uses public string Name { get; set; } it will work but if it uses public string Name; it will not be able to access the value and instead will display the object type for each line in the combo box.

Convert integer into its character equivalent, where 0 => a, 1 => b, etc

Assuming you want lower case letters:

var chr = String.fromCharCode(97 + n); // where n is 0, 1, 2 ...

97 is the ASCII code for lower case 'a'. If you want uppercase letters, replace 97 with 65 (uppercase 'A'). Note that if n > 25, you will get out of the range of letters.

UndefinedMetricWarning: F-score is ill-defined and being set to 0.0 in labels with no predicted samples

The accepted answer explains already well why the warning occurs. If you simply want to control the warnings, one could use precision_recall_fscore_support. It offers a (semi-official) argument warn_for that could be used to mute the warnings.

(_, _, f1, _) = metrics.precision_recall_fscore_support(y_test, y_pred,
                                                        average='weighted', 
                                                        warn_for=tuple())

As mentioned already in some comments, use this with care.

JDBC ResultSet: I need a getDateTime, but there is only getDate and getTimeStamp

java.util.Date date;
Timestamp timestamp = resultSet.getTimestamp(i);
if (timestamp != null)
    date = new java.util.Date(timestamp.getTime()));

Then format it the way you like.

How do I disable orientation change on Android?

In your androidmanifest.xml file:

   <activity android:name="MainActivity" android:configChanges="keyboardHidden|orientation">

or

@Override
public void onConfigurationChanged(Configuration newConfig) {
    super.onConfigurationChanged(newConfig);
    setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
}

How do I perform a JAVA callback between classes?

Use the observer pattern. It works like this:

interface MyListener{
    void somethingHappened();
}

public class MyForm implements MyListener{
    MyClass myClass;
    public MyForm(){
        this.myClass = new MyClass();
        myClass.addListener(this);
    }
    public void somethingHappened(){
       System.out.println("Called me!");
    }
}
public class MyClass{
    private List<MyListener> listeners = new ArrayList<MyListener>();

    public void addListener(MyListener listener) {
        listeners.add(listener);
    }
    void notifySomethingHappened(){
        for(MyListener listener : listeners){
            listener.somethingHappened();
        }
    }
}

You create an interface which has one or more methods to be called when some event happens. Then, any class which needs to be notified when events occur implements this interface.

This allows more flexibility, as the producer is only aware of the listener interface, not a particular implementation of the listener interface.

In my example:

MyClass is the producer here as its notifying a list of listeners.

MyListener is the interface.

MyForm is interested in when somethingHappened, so it is implementing MyListener and registering itself with MyClass. Now MyClass can inform MyForm about events without directly referencing MyForm. This is the strength of the observer pattern, it reduces dependency and increases reusability.

Get current time in milliseconds using C++ and Boost

// Get current date/time in milliseconds.
#include "boost/date_time/posix_time/posix_time.hpp"
namespace pt = boost::posix_time;

int main()
{
     pt::ptime current_date_microseconds = pt::microsec_clock::local_time();

    long milliseconds = current_date_microseconds.time_of_day().total_milliseconds();

    pt::time_duration current_time_milliseconds = pt::milliseconds(milliseconds);

    pt::ptime current_date_milliseconds(current_date_microseconds.date(), 
                                        current_time_milliseconds);

    std::cout << "Microseconds: " << current_date_microseconds 
              << " Milliseconds: " << current_date_milliseconds << std::endl;

    // Microseconds: 2013-Jul-12 13:37:51.699548 Milliseconds: 2013-Jul-12 13:37:51.699000
}

Cannot import scipy.misc.imread

If you have Pillow installed with scipy and it is still giving you error then check your scipy version because it has been removed from scipy since 1.3.0rc1.

rather install scipy 1.1.0 by :

pip install scipy==1.1.0

check https://github.com/scipy/scipy/issues/6212


The method imread in scipy.misc requires the forked package of PIL named Pillow. If you are having problem installing the right version of PIL try using imread in other packages:

from matplotlib.pyplot import imread
im = imread(image.png)

To read jpg images without PIL use:

import cv2 as cv
im = cv.imread(image.jpg)

You can try from scipy.misc.pilutil import imread instead of from scipy.misc import imread

Please check the GitHub page : https://github.com/amueller/mglearn/issues/2 for more details.

Refreshing page on click of a button

I'd suggest <a href='page1.jsp'>Refresh</a>.

Selenium Finding elements by class name in python

As per the HTML:

<html>
    <body>
    <p class="content">Link1.</p>
    </body>
<html>
<html>
    <body>
    <p class="content">Link2.</p>
    </body>
<html>

Two(2) <p> elements are having the same class content.

So to filter the elements having the same class i.e. content and create a list you can use either of the following Locator Strategies:

  • Using class_name:

    elements = driver.find_elements_by_class_name("content")
    
  • Using css_selector:

     elements = driver.find_elements_by_css_selector(".content")
    
  • Using xpath:

    elements = driver.find_elements_by_xpath("//*[@class='content']")
    

Ideally, to click on the element you need to induce WebDriverWait for the visibility_of_all_elements_located() and you can use either of the following Locator Strategies:

  • Using CLASS_NAME:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CLASS_NAME, "content")))
    
  • Using CSS_SELECTOR:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.CSS_SELECTOR, ".content")))
    
  • Using XPATH:

    elements = WebDriverWait(driver, 20).until(EC.visibility_of_all_elements_located((By.XPATH, "//*[@class='content']")))
    
  • Note : You have to add the following imports :

    from selenium.webdriver.support.ui import WebDriverWait
    from selenium.webdriver.common.by import By
    from selenium.webdriver.support import expected_conditions as EC
    

References

You can find a couple of relevant discussions in:

Stop on first error

Maybe you want set -e:

www.davidpashley.com/articles/writing-robust-shell-scripts.html#id2382181:

This tells bash that it should exit the script if any statement returns a non-true return value. The benefit of using -e is that it prevents errors snowballing into serious issues when they could have been caught earlier. Again, for readability you may want to use set -o errexit.

Best way to find if an item is in a JavaScript array?

As of ECMAScript 2016 you can use includes()

arr.includes(obj);

If you want to support IE or other older browsers:

function include(arr,obj) {
    return (arr.indexOf(obj) != -1);
}

EDIT: This will not work on IE6, 7 or 8 though. The best workaround is to define it yourself if it's not present:

  1. Mozilla's (ECMA-262) version:

       if (!Array.prototype.indexOf)
       {
    
            Array.prototype.indexOf = function(searchElement /*, fromIndex */)
    
         {
    
    
         "use strict";
    
         if (this === void 0 || this === null)
           throw new TypeError();
    
         var t = Object(this);
         var len = t.length >>> 0;
         if (len === 0)
           return -1;
    
         var n = 0;
         if (arguments.length > 0)
         {
           n = Number(arguments[1]);
           if (n !== n)
             n = 0;
           else if (n !== 0 && n !== (1 / 0) && n !== -(1 / 0))
             n = (n > 0 || -1) * Math.floor(Math.abs(n));
         }
    
         if (n >= len)
           return -1;
    
         var k = n >= 0
               ? n
               : Math.max(len - Math.abs(n), 0);
    
         for (; k < len; k++)
         {
           if (k in t && t[k] === searchElement)
             return k;
         }
         return -1;
       };
    
     }
    
  2. Daniel James's version:

     if (!Array.prototype.indexOf) {
       Array.prototype.indexOf = function (obj, fromIndex) {
         if (fromIndex == null) {
             fromIndex = 0;
         } else if (fromIndex < 0) {
             fromIndex = Math.max(0, this.length + fromIndex);
         }
         for (var i = fromIndex, j = this.length; i < j; i++) {
             if (this[i] === obj)
                 return i;
         }
         return -1;
       };
     }
    
  3. roosteronacid's version:

     Array.prototype.hasObject = (
       !Array.indexOf ? function (o)
       {
         var l = this.length + 1;
         while (l -= 1)
         {
             if (this[l - 1] === o)
             {
                 return true;
             }
         }
         return false;
       } : function (o)
       {
         return (this.indexOf(o) !== -1);
       }
     );
    

changing source on html5 video tag

Another way you can do in Jquery.

HTML

<video id="videoclip" controls="controls" poster="" title="Video title">
    <source id="mp4video" src="video/bigbunny.mp4" type="video/mp4"  />
</video>

<div class="list-item">
     <ul>
         <li class="item" data-video = "video/bigbunny.mp4"><a href="javascript:void(0)">Big Bunny.</a></li>
     </ul>
</div>

Jquery

$(".list-item").find(".item").on("click", function() {
        let videoData = $(this).data("video");
        let videoSource = $("#videoclip").find("#mp4video");
        videoSource.attr("src", videoData);
        let autoplayVideo = $("#videoclip").get(0);
        autoplayVideo.load();
        autoplayVideo.play();
    });

The #include<iostream> exists, but I get an error: identifier "cout" is undefined. Why?

The problem is the std namespace you are missing. cout is in the std namespace.
Add using namespace std; after the #include

File URL "Not allowed to load local resource" in the Internet Browser

For people do not like to modify chrome's security options, we can simply start a python http server from directory which contains your local file:

python -m SimpleHTTPServer

and for python 3:

python3 -m http.server

Now you can reach any local file directly from your js code or externally with http://127.0.0.1:8000/some_file.txt

How to get the connection String from a database

Easiest way my friends, is to open the server explorer tab on visual studio 2019 (in my case), and then try to create the connection to the database. After creating a succesful connection just right click on it and go to propierties. There you will find a string connection field with the correct syntax!...This worked for me because I knew my server's name before hand....just couldn't figure out the correct syntax to run my ef scaffold...

Select Tag Helper in ASP.NET Core MVC

You can also use IHtmlHelper.GetEnumSelectList.

    // Summary:
    //     Returns a select list for the given TEnum.
    //
    // Type parameters:
    //   TEnum:
    //     Type to generate a select list for.
    //
    // Returns:
    //     An System.Collections.Generic.IEnumerable`1 containing the select list for the
    //     given TEnum.
    //
    // Exceptions:
    //   T:System.ArgumentException:
    //     Thrown if TEnum is not an System.Enum or if it has a System.FlagsAttribute.
    IEnumerable<SelectListItem> GetEnumSelectList<TEnum>() where TEnum : struct;

MySQL string replace

UPDATE your_table
SET your_field = REPLACE(your_field, 'articles/updates/', 'articles/news/')
WHERE your_field LIKE '%articles/updates/%'

Now rows that were like

http://www.example.com/articles/updates/43

will be

http://www.example.com/articles/news/43

http://www.electrictoolbox.com/mysql-find-replace-text/

Sort dataGridView columns in C# ? (Windows Form)

Use Datatable.Default.Sort property and then bind it to the datagridview.

Nullable type as a generic parameter possible?

This may be a dead thread, but I tend to use the following:

public static T? GetValueOrNull<T>(this DbDataRecord reader, string columnName)
where T : struct 
{
    return reader[columnName] as T?;
}

How to compare two files in Notepad++ v6.6.8

I give the answer because I need to compare 2 files in notepad++ and there is no option available.

So first enable the plugin manager as asked by question here, Then follow this step to compare 2 files which is free in this software.

1.open notepad++, go to

Plugin -> Plugin Manager -> Show Plugin Manager

2.Show the available plugin list, choose Compare and Install

3.Restart Notepad++.

http://www.technicaloverload.com/compare-two-files-using-notepad/

In Java what is the syntax for commenting out multiple lines?

/* 
LINES I WANT COMMENTED 
LINES I WANT COMMENTED 
LINES I WANT COMMENTED 
*/

Tools: replace not replacing in Android manifest

Declare your manifest header like this

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.yourpackage"
    xmlns:tools="http://schemas.android.com/tools">

Then you can add to your application tag the following attribute:

<application
    tools:replace="icon, label" ../>

For example I need to replace icon and label. Good luck!

How to detect lowercase letters in Python?

To check if a character is lower case, use the islower method of str. This simple imperative program prints all the lowercase letters in your string:

for c in s:
    if c.islower():
         print c

Note that in Python 3 you should use print(c) instead of print c.


Possibly ending up with assigning those letters to a different variable.

To do this I would suggest using a list comprehension, though you may not have covered this yet in your course:

>>> s = 'abCd'
>>> lowercase_letters = [c for c in s if c.islower()]
>>> print lowercase_letters
['a', 'b', 'd']

Or to get a string you can use ''.join with a generator:

>>> lowercase_letters = ''.join(c for c in s if c.islower())
>>> print lowercase_letters
'abd'

How do I add a Maven dependency in Eclipse?

I have faced same problem with maven dependencies, eg: unfortunetly your maven dependencies deleted from your buildpath,then you people get lot of exceptions,if you follow below process you can easily resolve this issue.

 Right click on project >> maven >> updateProject >> selectProject >> OK

Use jQuery to change value of a label

.text is correct, the following code works for me:

$('#lb'+(n+1)).text(a[i].attributes[n].name+": "+ a[i].attributes[n].value);

Add Foreign Key relationship between two Databases

If you need rock solid integrity, have both tables in one database, and use an FK constraint. If your parent table is in another database, nothing prevents anyone from restoring that parent database from an old backup, and then you have orphans.

This is why FK between databases is not supported.

html cellpadding the left side of a cell

This is what css is for... HTML doesn't allow for unequal padding. When you say that you don't want to use style sheets, does this mean you're OK with inline css?

<table>
    <tr>
        <td style="padding: 5px 10px 5px 5px;">Content</td>
        <td style="padding: 5px 10px 5px 5px;">Content</td>
    </tr>
</table>

You could also use JS to do this if you're desperate not to use stylesheets for some reason.

Bootstrap - How to add a logo to navbar class?

Use a image style width and height 100% . This will do the trick, because the image can be resized based on the container.

Example:

<a class="navbar-brand" href="#" style="padding: 4px;margin:auto"> <img src="images/logo.png" style="height:100%;width: auto;" title="mycompanylogo"></a>

jQuery location href

I think you are looking for:

window.location = 'http://someUrl.com';

It's not jQuery; it's pure JavaScript.

Replacing H1 text with a logo image: best method for SEO and accessibility?

I don't know but this is the format have used...

<h1>
    <span id="site-logo" title="xxx" href="#" target="_self">
        <img src="http://www.xxx.com/images/xxx.png" alt="xxx" width="xxx" height="xxx" />
        <a style="display:none">
            <strong>xxx</strong>
        </a>
    </span>
</h1>

Simple and it has not done my site any harm as far as I can see. You could css it but I don't see it loading any faster.

Create stacked barplot where each stack is scaled to sum to 100%

Here's a solution using that ggplot package (version 3.x) in addition to what you've gotten so far.

We use the position argument of geom_bar set to position = "fill". You may also use position = position_fill() if you want to use the arguments of position_fill() (vjust and reverse).

Note that your data is in a 'wide' format, whereas ggplot2 requires it to be in a 'long' format. Thus, we first need to gather the data.

library(ggplot2)
library(dplyr)
library(tidyr)

dat <- read.table(text = "    ONE TWO THREE
1   23  234 324
2   34  534 12
3   56  324 124
4   34  234 124
5   123 534 654",sep = "",header = TRUE)

# Add an id variable for the filled regions and reshape
datm <- dat %>% 
  mutate(ind = factor(row_number())) %>%  
  gather(variable, value, -ind)

ggplot(datm, aes(x = variable, y = value, fill = ind)) + 
    geom_bar(position = "fill",stat = "identity") +
    # or:
    # geom_bar(position = position_fill(), stat = "identity") 
    scale_y_continuous(labels = scales::percent_format())

example figure

How do you execute SQL from within a bash script?

As Bash doesn't have built in sql database connectivity... you will need to use some sort of third party tool.

How do I hide the bullets on my list for the sidebar?

You have a selector ul on line 252 which is setting list-style: square outside none (a square bullet). You'll have to change it to list-style: none or just remove the line.

If you only want to remove the bullets from that specific instance, you can use the specific selector for that list and its items as follows:

ul#groups-list.items-list { list-style: none }

Rails find_or_create_by more than one attribute?

Multiple attributes can be connected with an and:

GroupMember.find_or_create_by_member_id_and_group_id(4, 7)

(use find_or_initialize_by if you don't want to save the record right away)

Edit: The above method is deprecated in Rails 4. The new way to do it will be:

GroupMember.where(:member_id => 4, :group_id => 7).first_or_create

and

GroupMember.where(:member_id => 4, :group_id => 7).first_or_initialize

Edit 2: Not all of these were factored out of rails just the attribute specific ones.

https://github.com/rails/rails/blob/4-2-stable/guides/source/active_record_querying.md

Example

GroupMember.find_or_create_by_member_id_and_group_id(4, 7)

became

GroupMember.find_or_create_by(member_id: 4, group_id: 7)

How to remove close button on the jQuery UI dialog?

I catch the close event of the dialog box. This code then removes the <div> (#dhx_combo_list):

open: function(event, ui) { 
  //hide close button.
  $(this).parent().children().children('.ui-dialog-titlebar-close').click(function(){
    $("#dhx_combo_list").remove();
  });
},

Eclipse/Java code completion not working

I faced this problem, and spent hours trying to figure out the issue. tried to follow the steps mentioned in the different answers above, the solution I found is on the same lines as Mona suggested, but slightly different. Tried to add as a comment to Mona's answer but no option was available. Issue with my eclipse was, classpath somehow got corrupted and all the jars and dependent projects were missing. after taking the latest .classpath from repository it worked fine.

How to remove part of a string?

You can use str_replace(), which is defined as:

str_replace($search, $replace, $subject)

So you could write the code as:

$subject = 'REGISTER 11223344 here' ;
$search = '11223344' ;
$trimmed = str_replace($search, '', $subject) ;
echo $trimmed ;

If you need better matching via regular expressions you can use preg_replace().

bootstrap datepicker change date event doesnt fire up when manually editing dates or clearing date

I have this version about datetimepicker https://tempusdominus.github.io/bootstrap-4/ and for any reason doesn`t work the change event with jquery but with JS vanilla it does

I figure out like this

document.getElementById('date').onchange = function(){ ...the jquery code...}

I hope work for you

Ellipsis for overflow text in dropdown boxes

Found this absolute hack that actually works quite well:

https://codepen.io/nikitahl/pen/vyZbwR

Not CSS only though.

The basic gist is to have a container on the dropdown, .select-container in this case. That container has it's ::before set up to display content based on its data-content attribute/dataset, along with all of the overflow:hidden; text-overflow: ellipsis; and sizing necessary to make the ellipsis work.

When the select changes, javascript assigns the value (or you could retrieve the text of the option out of the select.options list) to the dataset.content of the container, and voila!

Copying content of the codepen here:

_x000D_
_x000D_
var selectContainer = document.querySelector(".select-container");_x000D_
var select = selectContainer.querySelector(".select");_x000D_
select.value = "lingua latina non penis canina";_x000D_
_x000D_
selectContainer.dataset.content = select.value;_x000D_
_x000D_
function handleChange(e) {_x000D_
  selectContainer.dataset.content = e.currentTarget.value;_x000D_
  console.log(select.value);_x000D_
}_x000D_
_x000D_
select.addEventListener("change", handleChange);
_x000D_
span {_x000D_
  margin: 0 10px 0 0;_x000D_
}_x000D_
_x000D_
.select-container {_x000D_
  position: relative;_x000D_
  display: inline-block;_x000D_
}_x000D_
_x000D_
.select-container::before {_x000D_
  content: attr(data-content);_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  right: 10px;_x000D_
  bottom: 0;_x000D_
  left: 0;_x000D_
  padding: 7px;_x000D_
  font: 11px Arial, sans-serif;_x000D_
  white-space: nowrap;_x000D_
  text-overflow: ellipsis;_x000D_
  overflow: hidden;_x000D_
  text-transform: capitalize;_x000D_
  pointer-events: none;_x000D_
}_x000D_
_x000D_
.select {_x000D_
  width: 80px;_x000D_
  padding: 5px;_x000D_
  appearance: none;_x000D_
  background: transparent url("https://cdn4.iconfinder.com/data/icons/ionicons/512/icon-arrow-down-b-128.png") no-repeat calc(~"100% - 5px") 7px;_x000D_
  background-size: 10px 10px;_x000D_
  color: transparent;_x000D_
}_x000D_
_x000D_
.regular {_x000D_
  display: inline-block;_x000D_
  margin: 10px 0 0;_x000D_
  .select {_x000D_
    color: #000;_x000D_
  }_x000D_
}
_x000D_
<span>Hack:</span><div class="select-container" data-content="">_x000D_
  <select class="select" id="words">_x000D_
    <option value="lingua latina non penis canina">Lingua latina non penis canina</option>_x000D_
    <option value="lorem">Lorem</option>_x000D_
    <option value="ipsum">Ipsum</option>_x000D_
    <option value="dolor">Dolor</option>_x000D_
    <option value="sit">Sit</option>_x000D_
    <option value="amet">Amet</option>_x000D_
    <option value="lingua">Lingua</option>_x000D_
    <option value="latina">Latina</option>_x000D_
    <option value="non">Non</option>_x000D_
    <option value="penis">Penis</option>_x000D_
    <option value="canina">Canina</option>_x000D_
  </select>_x000D_
</div>_x000D_
<br />_x000D_
_x000D_
<span>Regular:</span>_x000D_
<div class="regular">_x000D_
  <select style="width: 80px;">_x000D_
    <option value="lingua latina non penis canina">Lingua latina non penis canina</option>_x000D_
    <option value="lorem">Lorem</option>_x000D_
    <option value="ipsum">Ipsum</option>_x000D_
    <option value="dolor">Dolor</option>_x000D_
    <option value="sit">Sit</option>_x000D_
    <option value="amet">Amet</option>_x000D_
    <option value="lingua">Lingua</option>_x000D_
    <option value="latina">Latina</option>_x000D_
    <option value="non">Non</option>_x000D_
    <option value="penis">Penis</option>_x000D_
    <option value="canina">Canina</option>_x000D_
  </select>_x000D_
</div>
_x000D_
_x000D_
_x000D_

AngularJS error: 'argument 'FirstCtrl' is not a function, got undefined'

Another nice one: Accidentally redefining modules. I copy/pasted stuff a little too eagerly earlier today and ended up having a module definition somewhere, that I overrode with my controller definitions:

// controllers.js - dependencies in one place, perfectly fine
angular.module('my.controllers', [/* dependencies */]);

Then in my definitions, I was supposed to reference it like so:

// SomeCtrl.js - grab the module, add the controller
angular.module('my.controllers')
 .controller('SomeCtrl', function() { /* ... */ });

What I did instead, was:

// Do not try this at home!

// SomeCtrl.js
angular.module('my.controllers', []) // <-- redefined module, no harm done yet
  .controller('SomeCtrl', function() { /* ... */ });

// SomeOtherCtrl.js
angular.module('my.controllers', []) // <-- redefined module - SomeCtrl no longer accessible
  .controller('SomeOtherCtrl', function() { /* ... */ });

Note the extra bracket in the call to angular.module.

How do I delete specific lines in Notepad++?

Investigate what is your EOL, \n or \r\n. Then replace .*#region.*\r\n with nothing in regexpr mode.

How to insert values in table with foreign key using MySQL?

Case 1

INSERT INTO tab_student (name_student, id_teacher_fk)
    VALUES ('dan red', 
           (SELECT id_teacher FROM tab_teacher WHERE name_teacher ='jason bourne')

it is advisable to store your values in lowercase to make retrieval easier and less error prone

Case 2

mysql docs

INSERT INTO tab_teacher (name_teacher) 
    VALUES ('tom stills')
INSERT INTO tab_student (name_student, id_teacher_fk)
    VALUES ('rich man', LAST_INSERT_ID())

Check number of arguments passed to a Bash script

There is a lot of good information here, but I wanted to add a simple snippet that I find useful.

How does it differ from some above?

  • Prints usage to stderr, which is more proper than printing to stdout
  • Return with exit code mentioned in this other answer
  • Does not make it into a one liner...
_usage(){
    _echoerr "Usage: $0 <args>"
}

_echoerr(){
    echo "$*" >&2
}

if [ "$#" -eq 0 ]; then # NOTE: May need to customize this conditional
    _usage
    exit 2
fi
main "$@"

Why is there an unexplainable gap between these inline-block div elements?

The easiest fix is to just float the container. (eg. float: left;) On another note, each id should be unique, meaning you can't use the same id twice in the same HTML document. You should use classes instead, where you can use the same class for multiple elements.

.container {
    position: relative;
    background: rgb(255, 100, 0);
    margin: 0;
    width: 40%;
    height: 100px;
    float: left;
}

How to make MySQL handle UTF-8 properly

These tips on MySQL and UTF-8 may be helpful. Unfortunately, they don't constitute a full solution, just common gotchas.

How to call loading function with React useEffect only once

Pass an empty array as the second argument to useEffect. This effectively tells React, quoting the docs:

This tells React that your effect doesn’t depend on any values from props or state, so it never needs to re-run.

Here's a snippet which you can run to show that it works:

_x000D_
_x000D_
function App() {_x000D_
  const [user, setUser] = React.useState(null);_x000D_
_x000D_
  React.useEffect(() => {_x000D_
    fetch('https://randomuser.me/api/')_x000D_
      .then(results => results.json())_x000D_
      .then(data => {_x000D_
        setUser(data.results[0]);_x000D_
      });_x000D_
  }, []); // Pass empty array to only run once on mount._x000D_
  _x000D_
  return <div>_x000D_
    {user ? user.name.first : 'Loading...'}_x000D_
  </div>;_x000D_
}_x000D_
_x000D_
ReactDOM.render(<App/>, document.getElementById('app'));
_x000D_
<script src="https://unpkg.com/[email protected]/umd/react.development.js"></script>_x000D_
<script src="https://unpkg.com/[email protected]/umd/react-dom.development.js"></script>_x000D_
_x000D_
<div id="app"></div>
_x000D_
_x000D_
_x000D_

Pie chart with jQuery

Check TeeChart for Javascript

  • Free for non-commercial use.

  • Includes plugins for jQuery, Node.js, WordPress, Drupal, Joomla, Microsoft TypeScript, etc...

  • Interactive demos here and here.

  • Some screenshots of some of the demos:

TeeChart Javascript - Bars

TeeChart Javascript - Pie

TeeChart Javascript - Points

call a static method inside a class?

This is a very late response, but adds some detail on the previous answers

When it comes to calling static methods in PHP from another static method on the same class, it is important to differentiate between self and the class name.

Take for instance this code:

class static_test_class {
    public static function test() {
        echo "Original class\n";
    }

    public static function run($use_self) {
        if($use_self) {
            self::test();
        } else {
            $class = get_called_class();
            $class::test(); 
        }
    }
}

class extended_static_test_class extends static_test_class {
    public static function test() {
        echo "Extended class\n";
    }
}

extended_static_test_class::run(true);
extended_static_test_class::run(false);

The output of this code is:

Original class

Extended class

This is because self refers to the class the code is in, rather than the class of the code it is being called from.

If you want to use a method defined on a class which inherits the original class, you need to use something like:

$class = get_called_class();
$class::function_name(); 

How to end a session in ExpressJS

Never mind, it's req.session.destroy();

Should I use JSLint or JSHint JavaScript validation?

Well, Instead of doing manual lint settings we can include all the lint settings at the top of our JS file itself e.g.

Declare all the global var in that file like:

/*global require,dojo,dojoConfig,alert */

Declare all the lint settings like:

/*jslint browser:true,sloppy:true,nomen:true,unparam:true,plusplus:true,indent:4 */

Hope this will help you :)

How to store a large (10 digits) integer?

Your concrete example could be stored in long (or java.lang.Long if this is necessary).

If at any point you need bigger numbers, you can try java.math.BigInteger (if integer), or java.math.BigDecimal (if decimal)

What should a Multipart HTTP request with multiple files look like?

Well, note that the request contains binary data, so I'm not posting the request as such - instead, I've converted every non-printable-ascii character into a dot (".").

POST /cgi-bin/qtest HTTP/1.1
Host: aram
User-Agent: Mozilla/5.0 Gecko/2009042316 Firefox/3.0.10
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
Referer: http://aram/~martind/banner.htm
Content-Type: multipart/form-data; boundary=2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Length: 514

--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile1"; filename="r.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile2"; filename="g.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f
Content-Disposition: form-data; name="datafile3"; filename="b.gif"
Content-Type: image/gif

GIF87a.............,...........D..;
--2a8ae6ad-f4ad-4d9a-a92c-6d217011fe0f--

Note that every line (including the last one) is terminated by a \r\n sequence.

JavaScript private methods

You have to put a closure around your actual constructor-function, where you can define your private methods. To change data of the instances through these private methods, you have to give them "this" with them, either as an function argument or by calling this function with .apply(this) :

var Restaurant = (function(){
    var private_buy_food = function(that){
        that.data.soldFood = true;
    }
    var private_take_a_shit = function(){
        this.data.isdirty = true;   
    }
    // New Closure
    function restaurant()
    {
        this.data = {
            isdirty : false,
            soldFood: false,
        };
    }

    restaurant.prototype.buy_food = function()
    {
       private_buy_food(this);
    }
    restaurant.prototype.use_restroom = function()
    {
       private_take_a_shit.call(this);
    }
    return restaurant;
})()

// TEST:

var McDonalds = new Restaurant();
McDonalds.buy_food();
McDonalds.use_restroom();
console.log(McDonalds);
console.log(McDonalds.__proto__);

How to build a Debian/Ubuntu package from source?

I believe this is the Debian package 'bible'.

Well, it's the Debian new maintainer's guide, so a lot of it won't be applicable, but they do cover what goes where.

Formatting dates on X axis in ggplot2

Can you use date as a factor?

Yes, but you probably shouldn't.

...or should you use as.Date on a date column?

Yes.

Which leads us to this:

library(scales)
df$Month <- as.Date(df$Month)
ggplot(df, aes(x = Month, y = AvgVisits)) + 
  geom_bar(stat = "identity") +
  theme_bw() +
  labs(x = "Month", y = "Average Visits per User") +
  scale_x_date(labels = date_format("%m-%Y"))

enter image description here

in which I've added stat = "identity" to your geom_bar call.

In addition, the message about the binwidth wasn't an error. An error will actually say "Error" in it, and similarly a warning will always say "Warning" in it. Otherwise it's just a message.

How to upload files on server folder using jsp

I found the similar problem and found the solution and i have blogged about how to upload the file using JSP , In that example i have used the absolute path. Note that if you want to route to some other URL based location you can put a ESB like WSO2 ESB

No value accessor for form control with name: 'recipient'

You should add the ngDefaultControl attribute to your input like this:

<md-input
    [(ngModel)]="recipient"
    name="recipient"
    placeholder="Name"
    class="col-sm-4"
    (blur)="addRecipient(recipient)"
    ngDefaultControl>
</md-input>

Taken from comments in this post:

angular2 rc.5 custom input, No value accessor for form control with unspecified name

Note: For later versions of @angular/material:

Nowadays you should instead write:

<md-input-container>
    <input
        mdInput
        [(ngModel)]="recipient"
        name="recipient"
        placeholder="Name"
        (blur)="addRecipient(recipient)">
</md-input-container>

See https://material.angular.io/components/input/overview

Close dialog on click (anywhere)

A bit late but this is a solution that worked for me. Perfect if your modal is inside the overlay tag. So, the modal will close when you click anywhere outside the modal content.

HTML

<div class="modal">  
  <div class="overlay">
    <div class="modal-content">
      <p>HELLO WORLD!</p>
    </div>
  </div>
</div>

JS

$(document).on("click", function(event) {
  if ($(event.target).has(".modal-content").length) {
    $(".modal").hide();
  }
});

Here is a working example

Different CURRENT_TIMESTAMP and SYSDATE in oracle

CURRENT_DATE and CURRENT_TIMESTAMP return the current date and time in the session time zone.

SYSDATE and SYSTIMESTAMP return the system date and time - that is, of the system on which the database resides.

If your client session isn't in the same timezone as the server the database is on (or says it isn't anyway, via your NLS settings), mixing the SYS* and CURRENT_* functions will return different values. They are all correct, they just represent different things. It looks like your server is (or thinks it is) in a +4:00 timezone, while your client session is in a +4:30 timezone.

You might also see small differences in the time if the clocks aren't synchronised, which doesn't seem to be an issue here.

Connecting to remote URL which requires authentication using Java

You can set the default authenticator for http requests like this:

Authenticator.setDefault (new Authenticator() {
    protected PasswordAuthentication getPasswordAuthentication() {
        return new PasswordAuthentication ("username", "password".toCharArray());
    }
});

Also, if you require more flexibility, you can check out the Apache HttpClient, which will give you more authentication options (as well as session support, etc.)

Convert integer to hex and hex to integer

To convert Hex strings to INT, I have used this in the past. It can be modified to convert any base to INT in fact (Octal, Binary, whatever)

Declare @Str varchar(200)
Set @str = 'F000BE1A'

Declare @ndx int
Set @ndx = Len(@str)
Declare @RunningTotal  BigInt
Set @RunningTotal = 0

While @ndx > 0
Begin
    Declare @Exponent BigInt
    Set @Exponent = Len(@Str) - @ndx

    Set @RunningTotal = @RunningTotal + 

    Power(16 * 1.0, @Exponent) *
    Case Substring(@str, @ndx, 1)
        When '0' then 0
        When '1' then 1
        When '2' then 2 
        When '3' then 3
        When '4' then 4
        When '5' then 5
        When '6' then 6
        When '7' then 7
        When '8' then 8
        When '9' then 9
        When 'A' then 10
        When 'B' then 11
        When 'C' then 12
        When 'D' then 13
        When 'E' then 14
        When 'F' then 15
    End
    Set @ndx = @ndx - 1
End

Print @RunningTotal

Vertically align text next to an image?

Use line-height:30px for the span so that text is align with the image:

<div>
  <img style="width:30px; height:30px;">
  <span style="line-height:30px;">Doesn't work.</span>
</div>

rails simple_form - hidden field - create?

= f.input_field :title, as: :hidden, value: "some value"

Is also an option. Note, however, that it skips any wrapper defined for your form builder.

How do I programmatically set the value of a select box element using JavaScript?

document.getElementById('leaveCode').value = '10';

That should set the selection to "Annual Leave"

At least one JAR was scanned for TLDs yet contained no TLDs

apache-tomcat-8.0.33

If you want to enable debug logging in tomcat for TLD scanned jars then you have to change /conf/logging.properties file in tomcat directory.

uncomment the line :
org.apache.jasper.servlet.TldScanner.level = FINE

FINE level is for debug log.

This should work for normal tomcat.

If the tomcat is running under eclipse. Then you have to set the path of tomcat logging.properties in eclipse.

  1. Open servers view in eclipse.Stop the server.Double click your tomcat server.
    This will open Overview window for the server.
  2. Click on Open launch configuration.This will open another window.
  3. Go to the Arguments tab(second tab).Go to VM arguments section.
  4. paste this two line there :-
    -Djava.util.logging.config.file="{CATALINA_HOME}\conf\logging.properties"
    -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager
    Here CATALINA_HOME is your PC's corresponding tomcat server directory.
  5. Save the Changes.Restart the server.

Now the jar files that scanned for TLDs should show in the log.

How do I invert BooleanToVisibilityConverter?

using System;
using System.Globalization;
using System.Windows;
using System.Windows.Data;

public sealed class BooleanToVisibilityConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var flag = false;
        if (value is bool)
        {
            flag = (bool)value;
        }
        else if (value is bool?)
        {
            var nullable = (bool?)value;
            flag = nullable.GetValueOrDefault();
        }
        if (parameter != null)
        {
            if (bool.Parse((string)parameter))
            {
                flag = !flag;
            }
        }
        if (flag)
        {
            return Visibility.Visible;
        }
        else
        {
            return Visibility.Collapsed;
        }
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        var back = ((value is Visibility) && (((Visibility)value) == Visibility.Visible));
        if (parameter != null)
        {
            if ((bool)parameter)
            {
                back = !back;
            }
        }
        return back;
    }
}

and then pass a true or false as the ConverterParameter

       <Grid.Visibility>
                <Binding Path="IsYesNoButtonSetVisible" Converter="{StaticResource booleanToVisibilityConverter}" ConverterParameter="true"/>
        </Grid.Visibility>

Cannot install packages inside docker Ubuntu image

I found that mounting a local volume over /tmp can cause permission issues when the "apt-get update" runs, which prevents the package cache from being populated. Hopefully, this isn't something most people do, but it's something else to look for if you see this issue.

Could not create SSL/TLS secure channel, despite setting ServerCertificateValidationCallback

In my case TLS1_2 was enabled both on client and server but the server was using MD5 while client disabled it. So, test both client and server on http://ssllabs.com or test using openssl/s_client to see what's happening. Also, check the selected cipher using Wireshark.

find vs find_by vs where

There is a difference between find and find_by in that find will return an error if not found, whereas find_by will return null.

Sometimes it is easier to read if you have a method like find_by email: "haha", as opposed to .where(email: some_params).first.

How do I extract part of a string in t-sql

substring(field, 1,3) will work on your examples.

select substring(field, 1,3) from table

Also, if the alphabetic part is of variable length, you can do this to extract the alphabetic part:

select substring(field, 1, PATINDEX('%[1234567890]%', field) -1) 
from table
where PATINDEX('%[1234567890]%', field) > 0

WPF - add static items to a combo box

<ComboBox Text="Something">
            <ComboBoxItem Content="Item1"></ComboBoxItem >
            <ComboBoxItem Content="Item2"></ComboBoxItem >
            <ComboBoxItem Content="Item3"></ComboBoxItem >
</ComboBox>

How to install Android Studio on Ubuntu?

The easiest method to install Android Studio (or any other developer tool) on Ubuntu is to use the snap package from Ubuntu Software store. No need to download Android Studio as zip, try to manually install it, add PPAs or fiddle with Java installation. The snap package bundles the latest Android Studio along with OpenJDK and all the necessary dependencies.

Step 1: Install Android Studio

Search "android studio" in Ubuntu Software, select the first entry that shows up and install it:

Search Android Studio on Ubuntu Software Android Studio on Ubuntu Software

Or if you prefer the command line way, run this in Terminal:

sudo snap install --classic android-studio

Step 2: Install Android SDK

Open the newly installed Android Studio from dashboard:

Android Studio app on Dash

Don't need to import anything if this is the first time you're installing it:

Import Dialog

The Setup Wizard'll guide you through installation:

Android Studio Setup Wizard

Select Standard install to get the latest SDK and Custom in-case you wanna change the SDK version or its install location. From here on, it's pretty straightforward, just click next-next and you'll have the SDK downloaded and installed.

Select Standard or Custom installation

Step 3: Setting PATHs (Optional)

This step might be useful if you want Android SDK's developer tool commands like adb, fastboot, aapt, etc available in Terminal. Might be needed by 3rd party dev platforms like React Native, Ionic, Cordova, etc and other tools too. For setting PATHs, edit your ~/.profile file:

gedit ~/.profile

and then add the following lines to it:

# Android SDK Tools PATH
export ANDROID_HOME=${HOME}/Android/Sdk
export PATH="${ANDROID_HOME}/tools:${PATH}"
export PATH="${ANDROID_HOME}/emulator:${PATH}"
export PATH="${ANDROID_HOME}/platform-tools:${PATH}"

If you changed SDK location at the end of Step 2, don't forget to change the line export ANDROID_HOME=${HOME}/Android/Sdk accordingly. Do a restart (or just logout and then log back in) for the PATHs to take effect.


Tested on Ubuntu 16.04LTS and above. Would work on 14.04LTS too if you install support for snap packages first.


Note: This question is similar to the AskUbuntu question "How to install Android Studio on Ubuntu?" and my answer equally applies. I'm reproducing my answer here to ensure a full complete answer exists rather than just a link.

Javascript: The prettiest way to compare one value against multiple values

Since nobody has added the obvious solution yet which works fine for two comparisons, I'll offer it:

if (foobar === foo || foobar === bar) {
     //do something
}

And, if you have lots of values (perhaps hundreds or thousands), then I'd suggest making a Set as this makes very clean and simple comparison code and it's fast at runtime:

// pre-construct the Set
var tSet = new Set(["foo", "bar", "test1", "test2", "test3", ...]);

// test the Set at runtime
if (tSet.has(foobar)) {
    // do something
}

For pre-ES6, you can get a Set polyfill of which there are many. One is described in this other answer.

PostgreSQL INSERT ON CONFLICT UPDATE (upsert) use all excluded values

Postgres hasn't implemented an equivalent to INSERT OR REPLACE. From the ON CONFLICT docs (emphasis mine):

It can be either DO NOTHING, or a DO UPDATE clause specifying the exact details of the UPDATE action to be performed in case of a conflict.

Though it doesn't give you shorthand for replacement, ON CONFLICT DO UPDATE applies more generally, since it lets you set new values based on preexisting data. For example:

INSERT INTO users (id, level)
VALUES (1, 0)
ON CONFLICT (id) DO UPDATE
SET level = users.level + 1;

How to create a data file for gnuplot?

This error usually means the file couldn't be found.

Can you see the file from the command line?

  1. Try specifying the full pathname.
  2. check line ending type (use 0x0d).
  3. is file open in another program?
  4. do you have read access to it?

How to check if IsNumeric

There's the TryParse method, which returns a bool indicating if the conversion was successful.

How to get folder path for ClickOnce application

path is pointing to a subfolder under c:\Documents & Settings

That's right. ClickOnce applications are installed under the profile of the user who installed them. Did you take the path that retrieving the info from the executing assembly gave you, and go check it out?

On windows Vista and Windows 7, you will find the ClickOnce cache here:

c:\users\username\AppData\Local\Apps\2.0\obfuscatedfoldername\obfuscatedfoldername

On Windows XP, you will find it here:

C:\Documents and Settings\username\LocalSettings\Apps\2.0\obfuscatedfoldername\obfuscatedfoldername

How do I replace all line breaks in a string with <br /> elements?

If the accepted answer isn't working right for you then you might try.

str.replace(new RegExp('\n','g'), '<br />')

It worked for me.

List of tables, db schema, dump etc using the Python sqlite3 API

Check out here for dump. It seems there is a dump function in the library sqlite3.

Javascript - Append HTML to container element without innerHTML

How to fish and while using strict code. There are two prerequisite functions needed at the bottom of this post.

xml_add('before', id_('element_after'), '<span xmlns="http://www.w3.org/1999/xhtml">Some text.</span>');

xml_add('after', id_('element_before'), '<input type="text" xmlns="http://www.w3.org/1999/xhtml" />');

xml_add('inside', id_('element_parent'), '<input type="text" xmlns="http://www.w3.org/1999/xhtml" />');

Add multiple elements (namespace only needs to be on the parent element):

xml_add('inside', id_('element_parent'), '<div xmlns="http://www.w3.org/1999/xhtml"><input type="text" /><input type="button" /></div>');

Dynamic reusable code:

function id_(id) {return (document.getElementById(id)) ? document.getElementById(id) : false;}

function xml_add(pos, e, xml)
{
 e = (typeof e == 'string' && id_(e)) ? id_(e) : e;

 if (e.nodeName)
 {
  if (pos=='after') {e.parentNode.insertBefore(document.importNode(new DOMParser().parseFromString(xml,'application/xml').childNodes[0],true),e.nextSibling);}
  else if (pos=='before') {e.parentNode.insertBefore(document.importNode(new DOMParser().parseFromString(xml,'application/xml').childNodes[0],true),e);}
  else if (pos=='inside') {e.appendChild(document.importNode(new DOMParser().parseFromString(xml,'application/xml').childNodes[0],true));}
  else if (pos=='replace') {e.parentNode.replaceChild(document.importNode(new DOMParser().parseFromString(xml,'application/xml').childNodes[0],true),e);}
  //Add fragment and have it returned.
 }
}

Where are Magento's log files located?

To create your custom log file, try this code

Mage::log('your debug message', null, 'yourlog_filename.log');

Refer this Answer

Add CSS class to a div in code behind

Button1.CssClass += " newClass";

This will not erase your original classes for that control. Try this, it should work.

500.19 - Internal Server Error - The requested page cannot be accessed because the related configuration data for the page is invalid

In my case I needed to install the IIS URL rewrite module 2.0 because it is being used in the web.config and this was the first time running site on new machine.

How to set the LDFLAGS in CMakeLists.txt?

Look at:

CMAKE_EXE_LINKER_FLAGS
CMAKE_MODULE_LINKER_FLAGS
CMAKE_SHARED_LINKER_FLAGS
CMAKE_STATIC_LINKER_FLAGS

Java: Identifier expected

Put your code in a method.

Try this:

public class MyClass {
    public static void main(String[] args) {
        UserInput input = new UserInput();
        input.name();
    }
}

Then "run" the class from your IDE

Remove files from Git commit

if you dont push your changes to git yet

git reset --soft HEAD~1

It will reset all the changes and revert to one commit back

If this is the last commit you made and you want to delete the file from local and remote repository try this :

git rm <file>
 git commit --amend

or even better :

reset first

git reset --soft HEAD~1

reset the unwanted file

git reset HEAD path/to/unwanted_file

commit again

git commit -c ORIG_HEAD  

Composer require runs out of memory. PHP Fatal error: Allowed memory size of 1610612736 bytes exhausted

Another solution from the manual:

Composer also respects a memory limit defined by the COMPOSER_MEMORY_LIMIT environment variable:

COMPOSER_MEMORY_LIMIT=-1 composer.phar <...>

Or in my case

export COMPOSER_MEMORY_LIMIT=-1
composer <...>

Connect to SQL Server Database from PowerShell

I did remove integrated security ... my goal is to log onto a sql server using a connection string WITH active directory username / password. When I do that it always fails. Does not matter the format ... sam company\user ... upn [email protected] ... basic username.

XPath Query: get attribute href from a tag

For the following HTML document:

<html>
  <body>
    <a href="http://www.example.com">Example</a> 
    <a href="http://www.stackoverflow.com">SO</a> 
  </body>
</html>

The xpath query /html/body//a/@href (or simply //a/@href) will return:

    http://www.example.com
    http://www.stackoverflow.com

To select a specific instance use /html/body//a[N]/@href,

    $ /html/body//a[2]/@href
    http://www.stackoverflow.com

To test for strings contained in the attribute and return the attribute itself place the check on the tag not on the attribute:

    $ /html/body//a[contains(@href,'example')]/@href
    http://www.example.com

Mixing the two:

    $ /html/body//a[contains(@href,'com')][2]/@href
    http://www.stackoverflow.com

How do I force files to open in the browser instead of downloading (PDF)?

While the following works well on firefox, it DOES NOT work on chrome and mobile browsers.

Content-Type: application/pdf
Content-Disposition: inline; filename="filename.pdf"

To fix the chrome & mobile browsers error, do the following:

  • Store your files on a directory in your project
  • Use the google PDF Viewer

Google PDF Viewer can be used as so:

<iframe src="http://docs.google.com/gview?url=http://example.com/path/to/my/directory/pdffile.pdf&embedded=true" frameborder="0"></iframe>

How to calculate a time difference in C++

Get the system time in milliseconds at the beginning, and again at the end, and subtract.

To get the number of milliseconds since 1970 in POSIX you would write:

struct timeval tv;

gettimeofday(&tv, NULL);
return ((((unsigned long long)tv.tv_sec) * 1000) +
        (((unsigned long long)tv.tv_usec) / 1000));

To get the number of milliseconds since 1601 on Windows you would write:

SYSTEMTIME systime;
FILETIME filetime;

GetSystemTime(&systime);
if (!SystemTimeToFileTime(&systime, &filetime))
    return 0;

unsigned long long ns_since_1601;
ULARGE_INTEGER* ptr = (ULARGE_INTEGER*)&ns_since_1601;

// copy the result into the ULARGE_INTEGER; this is actually
// copying the result into the ns_since_1601 unsigned long long.
ptr->u.LowPart = filetime.dwLowDateTime;
ptr->u.HighPart = filetime.dwHighDateTime;

// Compute the number of milliseconds since 1601; we have to
// divide by 10,000, since the current value is the number of 100ns
// intervals since 1601, not ms.
return (ns_since_1601 / 10000);

If you cared to normalize the Windows answer so that it also returned the number of milliseconds since 1970, then you would have to adjust your answer by 11644473600000 milliseconds. But that isn't necessary if all you care about is the elapsed time.

Do the parentheses after the type name make a difference with new?

The rules for new are analogous to what happens when you initialize an object with automatic storage duration (although, because of vexing parse, the syntax can be slightly different).

If I say:

int my_int; // default-initialize ? indeterminate (non-class type)

Then my_int has an indeterminate value, since it is a non-class type. Alternatively, I can value-initialize my_int (which, for non-class types, zero-initializes) like this:

int my_int{}; // value-initialize ? zero-initialize (non-class type)

(Of course, I can't use () because that would be a function declaration, but int() works the same as int{} to construct a temporary.)

Whereas, for class types:

Thing my_thing; // default-initialize ? default ctor (class type)
Thing my_thing{}; // value-initialize ? default-initialize ? default ctor (class type)

The default constructor is called to create a Thing, no exceptions.

So, the rules are more or less:

  • Is it a class type?
    • YES: The default constructor is called, regardless of whether it is value-initialized (with {}) or default-initialized (without {}). (There is some additional prior zeroing behavior with value-initialization, but the default constructor is always given the final say.)
    • NO: Were {} used?
      • YES: The object is value-initialized, which, for non-class types, more or less just zero-initializes.
      • NO: The object is default-initialized, which, for non-class types, leaves it with an indeterminate value (it effectively isn't initialized).

These rules translate precisely to new syntax, with the added rule that () can be substituted for {} because new is never parsed as a function declaration. So:

int* my_new_int = new int; // default-initialize ? indeterminate (non-class type)
Thing* my_new_thing = new Thing; // default-initialize ? default ctor (class type)
int* my_new_zeroed_int = new int(); // value-initialize ? zero-initialize (non-class type)
     my_new_zeroed_int = new int{}; // ditto
       my_new_thing = new Thing(); // value-initialize ? default-initialize ? default ctor (class type)

(This answer incorporates conceptual changes in C++11 that the top answer currently does not; notably, a new scalar or POD instance that would end up an with indeterminate value is now technically now default-initialized (which, for POD types, technically calls a trivial default constructor). While this does not cause much practical change in behavior, it does simplify the rules somewhat.)

How do I compile and run a program in Java on my Mac?

Download and install Eclipse, and you're good to go.
http://www.eclipse.org/downloads/

Apple provides its own version of Java, so make sure it's up-to-date.
http://developer.apple.com/java/download/


Eclipse is an integrated development environment. It has many features, but the ones that are relevant for you at this stage is:

  • The source code editor
    • With syntax highlighting, colors and other visual cues
    • Easy cross-referencing to the documentation to facilitate learning
  • Compiler
    • Run the code with one click
    • Get notified of errors/mistakes as you go

As you gain more experience, you'll start to appreciate the rest of its rich set of features.

Select data from date range between two dates

Check this query, i created this query to check whether the check in date over lap with any reservation dates

SELECT * FROM tbl_ReservedRooms
WHERE NOT ('@checkindate' NOT BETWEEN fromdate AND todate
  AND '@checkoutdate'  NOT BETWEEN fromdate AND todate)

this will retrun the details which are overlaping , to get the not overlaping details then remove the 'NOT' from the query

Setting default permissions for newly created files and sub-directories under a directory in Linux?

Here's how to do it using default ACLs, at least under Linux.

First, you might need to enable ACL support on your filesystem. If you are using ext4 then it is already enabled. Other filesystems (e.g., ext3) need to be mounted with the acl option. In that case, add the option to your /etc/fstab. For example, if the directory is located on your root filesystem:

/dev/mapper/qz-root   /    ext3    errors=remount-ro,acl   0  1

Then remount it:

mount -oremount /

Now, use the following command to set the default ACL:

setfacl -dm u::rwx,g::rwx,o::r /shared/directory

All new files in /shared/directory should now get the desired permissions. Of course, it also depends on the application creating the file. For example, most files won't be executable by anyone from the start (depending on the mode argument to the open(2) or creat(2) call), just like when using umask. Some utilities like cp, tar, and rsync will try to preserve the permissions of the source file(s) which will mask out your default ACL if the source file was not group-writable.

Hope this helps!

Best practice to look up Java Enum

We do all our enums like this when it comes to Rest/Json etc. It has the advantage that the error is human readable and also gives you the accepted value list. We are using a custom method MyEnum.fromString instead of MyEnum.valueOf, hope it helps.

public enum MyEnum {

    A, B, C, D;

    private static final Map<String, MyEnum> NAME_MAP = Stream.of(values())
            .collect(Collectors.toMap(MyEnum::toString, Function.identity()));

    public static MyEnum fromString(final String name) {
        MyEnum myEnum = NAME_MAP.get(name);
        if (null == myEnum) {
            throw new IllegalArgumentException(String.format("'%s' has no corresponding value. Accepted values: %s", name, Arrays.asList(values())));
        }
        return myEnum;
    }
}

so for example if you call

MyEnum value = MyEnum.fromString("X");

you'll get an IllegalArgumentException with the following message:

'X' has no corresponding value. Accepted values: [A, B, C, D]

you can change the IllegalArgumentException to a custom one.

Can I use if (pointer) instead of if (pointer != NULL)?

As others already answered well, they both are interchangeable.

Nonetheless, it's worth mentioning that there could be a case where you may want to use the explicit statement, i.e. pointer != NULL.

See also https://stackoverflow.com/a/60891279/2463963

Trigger an action after selection select2

//when a Department selecting
$('#department_id').on('select2-selecting', function (e) {
    console.log("Action Before Selected");
    var deptid=e.choice.id;
    var depttext=e.choice.text;
    console.log("Department ID "+deptid);
    console.log("Department Text "+depttext);
});

//when a Department removing
$('#department_id').on('select2-removing', function (e) {
    console.log("Action Before Deleted");
    var deptid=e.choice.id;
    var depttext=e.choice.text;
    console.log("Department ID "+deptid);
    console.log("Department Text "+depttext);
});

java.nio.file.Path for a classpath resource

Guessing that what you want to do, is call Files.lines(...) on a resource that comes from the classpath - possibly from within a jar.

Since Oracle convoluted the notion of when a Path is a Path by not making getResource return a usable path if it resides in a jar file, what you need to do is something like this:

Stream<String> stream = new BufferedReader(new InputStreamReader(ClassLoader.getSystemResourceAsStream("/filename.txt"))).lines();

SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax — PHP — PDO

Same pdo error in sql query while trying to insert into database value from multidimential array:

$sql = "UPDATE test SET field=arr[$s][a] WHERE id = $id";
$sth = $db->prepare($sql);    
$sth->execute();

Extracting array arr[$s][a] from sql query, using instead variable containing it fixes the problem.

Peak detection in a 2D array

Using persistent homology to analyze your data set I get the following result (click to enlarge):

Result

This is the 2D-version of the peak detection method described in this SO answer. The above figure simply shows 0-dimensional persistent homology classes sorted by persistence.

I did upscale the original dataset by a factor of 2 using scipy.misc.imresize(). However, note that I did consider the four paws as one dataset; splitting it into four would make the problem easier.

Methodology. The idea behind this quite simple: Consider the function graph of the function that assigns each pixel its level. It looks like this:

3D function graph

Now consider a water level at height 255 that continuously descents to lower levels. At local maxima islands pop up (birth). At saddle points two islands merge; we consider the lower island to be merged to the higher island (death). The so-called persistence diagram (of the 0-th dimensional homology classes, our islands) depicts death- over birth-values of all islands:

Persistence diagram

The persistence of an island is then the difference between the birth- and death-level; the vertical distance of a dot to the grey main diagonal. The figure labels the islands by decreasing persistence.

The very first picture shows the locations of births of the islands. This method not only gives the local maxima but also quantifies their "significance" by the above mentioned persistence. One would then filter out all islands with a too low persistence. However, in your example every island (i.e., every local maximum) is a peak you look for.

Python code can be found here.

convert string to number node.js

You do not have to install something.

parseInt(req.params.year, 10);

should work properly.

console.log(typeof parseInt(req.params.year)); // returns 'number'

What is your output, if you use parseInt? is it still a string?

Checking if a number is a prime number in Python

a = input('inter a number: ')
s = 0
if a == 1:  
    print a, 'is a prime'

else : 

    for i in range (2, a ):

        if a%i == 0:
            print a,' is not a prime number'
            s = 'true'
            break

    if s == 0 : print a,' is a prime number'

it worked with me just fine :D

How to save a base64 image to user's disk using JavaScript?

This Works

function saveBase64AsFile(base64, fileName) {
    var link = document.createElement("a");
    document.body.appendChild(link);
    link.setAttribute("type", "hidden");
    link.href = "data:text/plain;base64," + base64;
    link.download = fileName;
    link.click();  
    document.body.removeChild(link);
}

Based on the answer above but with some changes

Python - How to sort a list of lists by the fourth element in each list?

Use sorted() with a key as follows -

>>> unsorted_list = [['a','b','c','5','d'],['e','f','g','3','h'],['i','j','k','4','m']]
>>> sorted(unsorted_list, key = lambda x: int(x[3]))
[['e', 'f', 'g', '3', 'h'], ['i', 'j', 'k', '4', 'm'], ['a', 'b', 'c', '5', 'd']]

The lambda returns the fourth element of each of the inner lists and the sorted function uses that to sort those list. This assumes that int(elem) will not fail for the list.

Or use itemgetter (As Ashwini's comment pointed out, this method would not work if you have string representations of the numbers, since they are bound to fail somewhere for 2+ digit numbers)

>>> from operator import itemgetter
>>> sorted(unsorted_list, key = itemgetter(3))
[['e', 'f', 'g', '3', 'h'], ['i', 'j', 'k', '4', 'm'], ['a', 'b', 'c', '5', 'd']]

Java: Check the date format of current string is according to required format or not

DateFormat formatter = new SimpleDateFormat("dd/MM/yyyy");
formatter.setLenient(false);
try {
    Date date= formatter.parse("02/03/2010");
} catch (ParseException e) {
    //If input date is in different format or invalid.
}

formatter.setLenient(false) will enforce strict matching.

If you are using Joda-Time -

private boolean isValidDate(String dateOfBirth) {
        boolean valid = true;
        try {
            DateTimeFormatter formatter = DateTimeFormat.forPattern("dd/MM/yyyy");
            DateTime dob = formatter.parseDateTime(dateOfBirth);
        } catch (Exception e) {
            valid = false;
        }
        return valid;
    }

SOAP-ERROR: Parsing WSDL: Couldn't load from <URL>

Try this:

$Wsdl = 'http://xxxx.xxx.xx/webservice3.asmx?WSDL';
libxml_disable_entity_loader(false); //adding this worked for me
$Client = new SoapClient($Wsdl);
//Code...

undefined reference to boost::system::system_category() when compiling

in my case, adding -lboost_system was not enough, it still could not find it in my custom build environment. I had to use the advice at Get rid of "gcc - /usr/bin/ld: warning lib not found" and change my ./configure command to:

./configure CXXFLAGS="-I$HOME/include" LDFLAGS="-L$HOME/lib -Wl,-rpath-link,$HOME/lib" --with-boost-libdir=$HOME/lib --prefix=$HOME

for more details see Boost 1.51 : "error: could not link against boost_thread !"

How to convert an address into a Google Maps Link (NOT MAP)

The best way is to use this line:

var mapUrl = "http://maps.google.com/maps?f=q&amp;source=s_q&amp;hl=en&amp;geocode=&amp;q=16900+North+Bay+Road,+Sunny+Isles+Beach,+FL+33160&amp;aq=0&amp;sll=37.0625,-95.677068&amp;sspn=61.282355,146.513672&amp;ie=UTF8&amp;hq=&amp;hnear=16900+North+Bay+Road,+Sunny+Isles+Beach,+FL+33160&amp;spn=0.01628,0.025663&amp;z=14&amp;iwloc=A&amp;output=embed"

Remember to replace the first and second addresses when necessary.

You can look at work sample

How do I delete rows in a data frame?

By simplified sequence :

mydata[-(1:3 * 2), ]

By sequence :

mydata[seq(1, nrow(mydata), by = 2) , ]

By negative sequence :

mydata[-seq(2, nrow(mydata), by = 2) , ]

Or if you want to subset by selecting odd numbers:

mydata[which(1:nrow(mydata) %% 2 == 1) , ]

Or if you want to subset by selecting odd numbers, version 2:

mydata[which(1:nrow(mydata) %% 2 != 0) , ]

Or if you want to subset by filtering even numbers out:

mydata[!which(1:nrow(mydata) %% 2 == 0) , ]

Or if you want to subset by filtering even numbers out, version 2:

mydata[!which(1:nrow(mydata) %% 2 != 1) , ]

Setting multiple attributes for an element at once with JavaScript

Or create a function that creates an element including attributes from parameters

function elemCreate(elType){
  var element = document.createElement(elType);
  if (arguments.length>1){
    var props = [].slice.call(arguments,1), key = props.shift();
    while (key){ 
      element.setAttribute(key,props.shift());
      key = props.shift();
    }
  }
  return element;
}
// usage
var img = elemCreate('img',
            'width','100',
            'height','100',
            'src','http://example.com/something.jpeg');

FYI: height/width='100%' would not work using attributes. For a height/width of 100% you need the elements style.height/style.width

How do I animate constraint changes?

Swift solution:

yourConstraint.constant = 50
UIView.animate(withDuration: 1.0, animations: {
    yourView.layoutIfNeeded
})

How to remove element from array in forEach loop?

Use Array.prototype.filter instead of forEach:

var pre = document.getElementById('out');

function log(result) {
  pre.appendChild(document.createTextNode(result + '\n'));
}

var review = ['a', 'b', 'c', 'b', 'a', 'e'];
review = review.filter(item => item !== 'a');
log(review);

How do I show the number keyboard on an EditText in android?

editText.setRawInputType(InputType.TYPE_CLASS_NUMBER);

Starting a shell in the Docker Alpine container

Usually, an Alpine Linux image doesn't contain bash, Instead you can use /bin/ash, /bin/sh, ash or only sh.

/bin/ash

docker run -it --rm alpine /bin/ash

/bin/sh

docker run -it --rm alpine /bin/sh

ash

docker run -it --rm alpine ash

sh

docker run -it --rm alpine sh

I hope this information helps you.

How to list the size of each file and directory and sort by descending size in Bash?

Apparently --max-depth option is not in Mac OS X's version of the du command. You can use the following instead.

du -h -d 1 | sort -n

install apt-get on linux Red Hat server

wget http://dag.wieers.com/packages/apt/apt-0.5.15lorg3.1-4.el4.rf.i386.rpm

rpm -ivh apt-0.5.15lorg3.1-4.el4.rf.i386.rpm

wget http://dag.wieers.com/packages/rpmforge-release/rpmforge-release-0.3.4-1.el4.rf.i386.rpm

rpm -Uvh rpmforge-release-0.3.4-1.el4.rf.i386.rpm

maybe some URL is broken,please research it. Enjoy~~

Excel VBA - Range.Copy transpose paste

WorksheetFunction Transpose()

Instead of copying, pasting via PasteSpecial, and using the Transpose option you can simply type a formula

    =TRANSPOSE(Sheet1!A1:A5)

or if you prefer VBA:

    Dim v
    v = WorksheetFunction.Transpose(Sheet1.Range("A1:A5"))
    Sheet2.Range("A1").Resize(1, UBound(v)) = v

Note: alternatively you could use late-bound Application.Transpose instead.

MS help reference states that having a current version of Microsoft 365, one can simply input the formula in the top-left-cell of the target range, otherwise the formula must be entered as a legacy array formula via Ctrl+Shift+Enter to confirm it.

Versions Excel vers. 2007+, Mac since 2011, Excel for Microsoft 365

dll missing in JDBC

You need to set a -D system property called java.library.path that points at the directory containing the sqljdbc_auth.dll.

When to use NSInteger vs. int

If you dig into NSInteger's implementation:

#if __LP64__
typedef long NSInteger;
#else
typedef int NSInteger;
#endif

Simply, the NSInteger typedef does a step for you: if the architecture is 32-bit, it uses int, if it is 64-bit, it uses long. Using NSInteger, you don't need to worry about the architecture that the program is running on.

Anaconda site-packages

I installed miniconda and found all the installed packages in /miniconda3/pkgs

Self-reference for cell, column and row in worksheet functions

For a non-volatile solution, how about for 2007+:

for cell    =INDEX($A$1:$XFC$1048576,ROW(),COLUMN())
for column  =INDEX($A$1:$XFC$1048576,0,COLUMN())
for row     =INDEX($A$1:$XFC$1048576,ROW(),0)

I have weird bug on Excel 2010 where it won't accept the very last row or column for these formula (row 1048576 & column XFD), so you may need to reference these one short. Not sure if that's the same for any other versions so appreciate feedback and edit.

and for 2003 (INDEX became non-volatile in '97):

for cell    =INDEX($A$1:$IV$65536,ROW(),COLUMN())
for column  =INDEX($A$1:$IV$65536,0,COLUMN())
for row     =INDEX($A$1:$IV$65536,ROW(),0)

Can you change what a symlink points to after it is created?

Yes, you can!

$ ln -sfn source_file_or_directory_name softlink_name

Excel: VLOOKUP that returns true or false?

ISNA is the best function to use. I just did. I wanted all cells whose value was NOT in an array to conditionally format to a certain color.

=ISNA(VLOOKUP($A2,Sheet1!$A:$D,2,FALSE))

JSchException: Algorithm negotiation fail

add KexAlgorithms diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha??1 to your sshd_config on the server.

This worked, but make sure you restart sshd: sudo service sshd restart

Get last 5 characters in a string

Old thread, but just only to say: to use the classic Left(), Right(), Mid() right now you don't need to write the full path (Microsoft.VisualBasic.Strings). You can use fast and easily like this:

Strings.Right(yourString, 5)

How do I find the parent directory in C#?

I've found variants of System.IO.Path.Combine(myPath, "..") to be the easiest and most reliable. Even more so if what northben says is true, that GetParent requires an extra call if there is a trailing slash. That, to me, is unreliable.

Path.Combine makes sure you never go wrong with slashes.

.. behaves exactly like it does everywhere else in Windows. You can add any number of \.. to a path in cmd or explorer and it will behave exactly as I describe below.

Some basic .. behavior:

  1. If there is a file name, .. will chop that off:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..") => D:\Grandparent\Parent\

  1. If the path is a directory, .. will move up a level:

Path.Combine(@"D:\Grandparent\Parent\", "..") => D:\Grandparent\

  1. ..\.. follows the same rules, twice in a row:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", @"..\..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", @"..\..") => D:\

  1. And this has the exact same effect:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..", "..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", "..", "..") => D:\

Converting byte array to string in javascript

I think this would be more efficient:

function toBinString (arr) {
    var uarr = new Uint8Array(arr.map(function(x){return parseInt(x,2)}));
    var strings = [], chunksize = 0xffff;
    // There is a maximum stack size. We cannot call String.fromCharCode with as many arguments as we want
    for (var i=0; i*chunksize < uarr.length; i++){
        strings.push(String.fromCharCode.apply(null, uarr.subarray(i*chunksize, (i+1)*chunksize)));
    }
    return strings.join('');
}

How to install latest version of openssl Mac OS X El Capitan

To replace the old version with the new one, you need to change the link for it. Type that command to terminal.

brew link --force openssl

Check the version of openssl again. It should be changed.

ASP.NET Web Site or ASP.NET Web Application?

I recommend you watch the video Web Application Projects & Web Deployment Projects on the ASP.NET website which explains the difference in great detail, it was quite helpful to me.

By the way, don't get confused by the title, a great part of the video explains the difference between website projects and web application projects and why Microsoft re-introduced Web application projects in Visual studio 2005 (as you probably already know, it originally shipped with only website projects then web application projects were added in SP1). A great video I highly recommend for anyone who wants to know the difference.

How to fix Warning Illegal string offset in PHP

Magic word is: isset

Validate the entry:

if(isset($manta_option['iso_format_recent_works']) && $manta_option['iso_format_recent_works'] == 1){
    $theme_img = 'recent_works_thumbnail';
} else {
    $theme_img = 'recent_works_iso_thumbnail';
}

convert strtotime to date time format in php

Here is exp.

$date_search_strtotime = strtotime(date("Y-m-d"));
echo 'Now strtotime date : '.$date_search_strtotime;
echo '<br>';
echo 'Now date from strtotime : '.date('Y-m-d',$date_search_strtotime);

How to "select distinct" across multiple data frame columns in pandas?

I've tried different solutions. First was:

a_df=np.unique(df[['col1','col2']], axis=0)

and it works well for not object data Another way to do this and to avoid error (for object columns type) is to apply drop_duplicates()

a_df=df.drop_duplicates(['col1','col2'])[['col1','col2']]

You can also use SQL to do this, but it worked very slow in my case:

from pandasql import sqldf
q="""SELECT DISTINCT col1, col2 FROM df;"""
pysqldf = lambda q: sqldf(q, globals())
a_df = pysqldf(q)

How do I do logging in C# without using 3rd party libraries?

I used to write my own error logging until I discovered ELMAH. I've never been able to get the emailing part down quite as perfectly as ELMAH does.

WebView link click open default browser

You only need to add the following line

yourWebViewName.setWebViewClient(new WebViewClient());

Check this for official documentation.

Android - Adding at least one Activity with an ACTION-VIEW intent-filter after Updating SDK version 23

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.example.app"
tools:ignore="GoogleAppIndexingWarning">

You can remove the warning by adding xmlns:tools="http://schemas.android.com/tools" and tools:ignore="GoogleAppIndexingWarning" to the <manifest> tag.

Visual Studio 2017: Display method references

No luck with Code lens in Community editions.

Press Shift + F12 to find all references.

SQL Server - Convert varchar to another collation (code page) to fix character encoding

Must be used convert, not cast:

SELECT
 CONVERT(varchar(50), N'æøåáälcçcédnoöruýtžš')
 COLLATE Cyrillic_General_CI_AI

(http://blog.sqlpositive.com/2010/03/using-convert-with-collate-to-strip-accents-from-unicode-strings/)

How do I properly set the permgen size?

Completely removed from java 8 +
Partially removed from java 7 (interned Strings for example)
source

What is the string concatenation operator in Oracle?

DECLARE
     a      VARCHAR2(30);
     b      VARCHAR2(30);
     c      VARCHAR2(30);
 BEGIN
      a  := ' Abc '; 
      b  := ' def ';
      c  := a || b;
 DBMS_OUTPUT.PUT_LINE(c);  
   END;

output:: Abc def

How To: Execute command line in C#, get STD OUT results

 System.Diagnostics.ProcessStartInfo psi =
   new System.Diagnostics.ProcessStartInfo(@"program_to_call.exe");
 psi.RedirectStandardOutput = true;
 psi.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden;
 psi.UseShellExecute = false;
 System.Diagnostics.Process proc = System.Diagnostics.Process.Start(psi); ////
 System.IO.StreamReader myOutput = proc.StandardOutput;
 proc.WaitForExit(2000);
 if (proc.HasExited)
  {
      string output = myOutput.ReadToEnd();
 }