Programs & Examples On #Named entity recognition

Named-entity recognition (NER) (also known as entity identification and entity extraction) is a subtask of information extraction that seeks to locate and classify atomic elements in text into predefined categories such as the names of persons, organizations, locations, expressions of times, quantities, monetary values, percentages, etc.

File Upload without Form

Try this puglin simpleUpload, no need form

Html:

<input type="file" name="arquivo" id="simpleUpload" multiple >
<button type="button" id="enviar">Enviar</button>

Javascript:

$('#simpleUpload').simpleUpload({
  url: 'upload.php',
  trigger: '#enviar',
  success: function(data){
    alert('Envio com sucesso');

  }
});

What's the use of session.flush() in Hibernate

Flushing the Session gets the data that is currently in the session synchronized with what is in the database.

More on the Hibernate website:

flush() is useful, because there are absolutely no guarantees about when the Session executes the JDBC calls, only the order in which they are executed - except you use flush().

Is it possible to overwrite a function in PHP

A solution for the related case where you have an include file A that you can edit and want to override some of its functions in an include file B (or the main file):

Main File:

<?php
$Override=true; // An argument used in A.php
include ("A.php");
include ("B.php");
F1();
?>

Include File A:

<?php
if (!@$Override) {
   function F1 () {echo "This is F1() in A";}
}
?>

Include File B:

<?php
   function F1 () {echo "This is F1() in B";}
?>

Browsing to the main file displays "This is F1() in B".

How to iterate std::set?

How do you iterate std::set?

int main(int argc,char *argv[]) 
{
    std::set<int> mset;
    mset.insert(1); 
    mset.insert(2);
    mset.insert(3);

    for ( auto it = mset.begin(); it != mset.end(); it++ )
        std::cout << *it;
}

transform object to array with lodash

For me, this worked:

_.map(_.toPairs(data), d => _.fromPairs([d]));

It turns

{"a":"b", "c":"d", "e":"f"} 

into

[{"a":"b"}, {"c":"d"}, {"e":"f"}]

In Java, how do I get the difference in seconds between 2 dates?

You should do

org.joda.time.Seconds.secondBetween(date1, date2)

Oracle - how to remove white spaces?

you can use 'rpad' in your select query and specify the size ...

select rpad(a , 20) , rpad(b, 20) from x ;

where first parameter is your column name and second parameter is the size which you want to pad with .

C++ class forward declaration

I had this:

class paulzSprite;
...

struct spriteFrame
{
    spriteFrame(int, int, paulzSprite*, int, int);
    paulzSprite* pSprite; //points to the sprite class this struct frames
    static paulzSprite* pErase; //pointer to blanking sprite
    int x, y;
    int Xmin, Xmax, Ymin, Ymax; //limits, leave these to individual child classes, according to bitmap size
    bool move(int, int);
    bool DrawAt(int, int);
    bool dead;
};

spriteFrame::spriteFrame(int initx, int inity, paulzSprite* pSpr, int winWidth, int winHeight)
{
    x = initx;
    y= inity;
    pSprite = pSpr;
    Xmin = Ymin = 0;
    Xmax = winWidth - pSpr->width;
    Ymax = winHeight - pSpr->height;
    dead = false;
}

...

Got the same grief as in the original question. Only solved by moving the definition of paulzSprite to after that of spriteFrame. Shouldn't the compiler be smarter than this (VC++, VS 11 Beta)?

And btw, I wholeheartedly agree with Clifford's remark above "Pointers don't cause memory leaks, poor coding causes memory leaks". IMHO this is true of many other new "smart coding" features, which should not become a substitute for understanding what you are actually asking the computer to do.

How to check if a scope variable is undefined in AngularJS template?

Corrected:

HTML

  <p ng-show="getFooUndef(foo)">Show this if $scope.foo === undefined</p>

JS

$scope.foo = undefined;

$scope.getFooUndef = function(foo){
    return ( typeof foo === 'undefined' );
}

Fiddle: http://jsfiddle.net/oakley349/vtcff0w5/1/

How to change facet labels?

Simple solution (from here):

p <- ggplot(mtcars, aes(disp, drat)) + geom_point()
# Example (old labels)
p + facet_wrap(~am)


to_string <- as_labeller(c(`0` = "Zero", `1` = "One"))
# Example (New labels)
p + facet_wrap(~am, labeller = to_string)

Vagrant error : Failed to mount folders in Linux guest

The plugin vagrant-vbguest GitHub RubyGems solved my problem:

$ vagrant plugin install vagrant-vbguest

Output:

$ vagrant reload
==> default: Attempting graceful shutdown of VM...
...
==> default: Machine booted and ready!
GuestAdditions 4.3.12 running --- OK.
==> default: Checking for guest additions in VM...
==> default: Configuring and enabling network interfaces...
==> default: Exporting NFS shared folders...
==> default: Preparing to edit /etc/exports. Administrator privileges will be required...
==> default: Mounting NFS shared folders...
==> default: VM already provisioned. Run `vagrant provision` or use `--provision` to force it

Just make sure you are running the latest version of VirtualBox

How to strip comma in Python string

This will strip all commas from the text and left justify it.

for row in inputfile:
    place = row['your_row_number_here'].strip(', ')

? ????? ??????

SQL-Server: Is there a SQL script that I can use to determine the progress of a SQL Server backup or restore process?

I had a similar issue when working on Database restore operation on MS SQL Server 2012.

However, for my own scenario, I just needed to see the progress of the DATABASE RESTORE operation in the script window

All I had to do was add the STATS option to the script:

USE master;
GO

ALTER DATABASE mydb SET SINGLE_USER WITH ROLLBACK IMMEDIATE;
GO
    
RESTORE DATABASE mydb
    FROM DISK = 'C:\Program Files\Microsoft SQL Server\MSSQL12.MSSQLSERVER\MSSQL\Backup\my_db_21-08-2020.bak'
    WITH REPLACE,
         STATS = 10,
         RESTART,
    MOVE 'my_db' TO 'C:\Program Files\Microsoft SQL Server\MSSQL12.MSSQLSERVER\MSSQL\DATA\my_db.mdf',
    MOVE 'my_db_log' TO 'C:\Program Files\Microsoft SQL Server\MSSQL12.MSSQLSERVER\MSSQL\DATA\mydb_log.ldf'
GO
    
ALTER DATABASE mydb SET MULTI_USER;
GO

And then I switched to the Messages tab of the Script window to see the progress of the DATABASE RESTORE operation:

enter image description here

If you want to get more information after the DATABASE RESTORE operation you can use this command suggested by eythort:

SELECT command, percent_complete, start_time FROM sys.dm_exec_requests where command = 'RESTORE DATABASE'

That's all.

I hope this helps

how to change directory using Windows command line

cd /driveName driveName:\pathNamw

How can I debug what is causing a connection refused or a connection time out?

Use a packet analyzer to intercept the packets to/from somewhere.com. Studying those packets should tell you what is going on.

Time-outs or connections refused could mean that the remote host is too busy.

how to redirect to home page

_x000D_
_x000D_
var url = location.href;_x000D_
var newurl = url.replace('some-domain.com','another-domain.com';);_x000D_
location.href=newurl;
_x000D_
_x000D_
_x000D_

See this answer https://stackoverflow.com/a/42291014/3901511

Java way to check if a string is palindrome

public static boolean istPalindrom(char[] word){
int i1 = 0;
int i2 = word.length - 1;
while (i2 > i1) {
    if (word[i1] != word[i2]) {
        return false;
    }
    ++i1;
    --i2;
}
return true;
}

Permission denied (publickey). fatal: The remote end hung up unexpectedly while pushing back to git repository

Googled "Permission denied (publickey). fatal: The remote end hung up unexpectedly", first result an exact SO dupe:

GitHub: Permission denied (publickey). fatal: The remote end hung up unexpectedly which links here in the accepted answer (from the original poster, no less): http://help.github.com/linux-set-up-git/

How to modify WooCommerce cart, checkout pages (main theme portion)

I used the page-checkout.php template to change the header for my cart page. I renamed it to page-cart.php in my /wp-content/themes/childtheme/woocommerce/. This gives you more control over the wrapping html, header and footer.

jQuery .scrollTop(); + animation

Try this instead:

var body = $("body, html");
var top = body.scrollTop() // Get position of the body
if(top!=0)
{
       body.animate({scrollTop :0}, 500,function(){
         //DO SOMETHING AFTER SCROLL ANIMATION COMPLETED
          alert('Hello');
      });
}

How to get current memory usage in android?

public static boolean isAppInLowMemory(Context context) {
    ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
    ActivityManager.MemoryInfo memoryInfo = new ActivityManager.MemoryInfo();
    activityManager.getMemoryInfo(memoryInfo);

    return memoryInfo.lowMemory;
}

Function pointer to member function

int (*x)() is not a pointer to member function. A pointer to member function is written like this: int (A::*x)(void) = &A::f;.

How to download a folder from github?

You have to download the whole project with either "Clone to desktop" button that will use native github program or "Download as zip".

And then search that folder in downloaded project.

Virtualbox "port forward" from Guest to Host

That's not possible. localhost always defaults to the loopback device on the local operating system.
As your virtual machine runs its own operating system it has its own loopback device which you cannot access from the outside.

If you want to access it e.g. in a browser, connect to it using the local IP instead:

http://192.168.180.1:8000

This is just an example of course, you can find out the actual IP by issuing an ifconfig command on a shell in the guest operating system.

Set custom attribute using JavaScript

For people coming from Google, this question is not about data attributes - OP added a non-standard attribute to their HTML object, and wondered how to set it.

However, you should not add custom attributes to your properties - you should use data attributes - e.g. OP should have used data-icon, data-url, data-target, etc.

In any event, it turns out that the way you set these attributes via JavaScript is the same for both cases. Use:

ele.setAttribute(attributeName, value);

to change the given attribute attributeName to value for the DOM element ele.

For example:

document.getElementById("someElement").setAttribute("data-id", 2);

Note that you can also use .dataset to set the values of data attributes, but as @racemic points out, it is 62% slower (at least in Chrome on macOS at the time of writing). So I would recommend using the setAttribute method instead.

.aspx vs .ashx MAIN difference

.aspx uses a full lifecycle (Init, Load, PreRender) and can respond to button clicks etc.
An .ashx has just a single ProcessRequest method.

Cannot find either column "dbo" or the user-defined function or aggregate "dbo.Splitfn", or the name is ambiguous

Since people will be coming from Google, make sure you're in the right database.

Running SQL in the 'master' database will often return this error.

HTML text input allow only numeric input

Use:

<script>
    function onlyNumber(id){ 
        var DataVal = document.getElementById(id).value;
        document.getElementById(id).value = DataVal.replace(/[^0-9]/g,'');
    }
</script>
<input type="text" id="1" name="1" onChange="onlyNumber(this.id);">

And if you want to update a value after press key, you can change onChange for onKeypress, onKeyDown or onKeyup. But event onKeypress doesn't running in any browsers.

How to clear a chart from a canvas so that hover events cannot be triggered?

Chart.js has a bug: Chart.controller(instance) registers any new chart in a global property Chart.instances[] and deletes it from this property on .destroy().

But at chart creation Chart.js also writes ._meta property to dataset variable:

var meta = dataset._meta[me.id];
if (!meta) {
   meta = dataset._meta[me.id] = {
       type: null,
       data: [],
       dataset: null,
       controller: null,
       hidden: null,     // See isDatasetVisible() comment
       xAxisID: null,
       yAxisID: null
   };

and it doesn't delete this property on destroy().

If you use your old dataset object without removing ._meta property, Chart.js will add new dataset to ._meta without deletion previous data. Thus, at each chart's re-initialization your dataset object accumulates all previous data.

In order to avoid this, destroy dataset object after calling Chart.destroy().

jQuery SVG vs. Raphael

For those who don't care about IE6/IE7, the same guy who wrote Raphael built an svg engine specifically for modern browsers: Snap.svg .. they have a really nice site with good docs: http://snapsvg.io

snap.svg couldn't be easier to use right out of the box and can manipulate/update existing SVGs or generate new ones. You can read this stuff on the snap.io about page but here's a quick run down:

Cons

  • To make use of snap's features you must forgo on support for older browsers. Raphael supports browsers like IE6/IE7, snap features are only supported by IE9 and up, Safari, Chrome, Firefox, and Opera.

Pros

  • Implements the full features of SVG like masking, clipping, patterns, full gradients, groups, and more.

  • Ability to work with existing SVGs: content does not have to be generated with Snap for it to work with Snap, allowing you to create the content with any common design tools.

  • Full animation support using a straightforward, easy-to-implement JavaScript API

  • Works with strings of SVGs (for example, SVG files loaded via Ajax) without having to actually render them first, similar to a resource container or sprite sheet.

check it out if you're interested: http://snapsvg.io

Flexbox not giving equal width to elements

To create elements with equal width using Flex, you should set to your's child (flex elements):

flex-basis: 25%;
flex-grow: 0;

It will give to all elements in row 25% width. They will not grow and go one by one.

Editing hosts file to redirect url?

Apply this trick.

First you need IP address of url you want to redirect to. Lets say you want to redirect to stackoverflow.com To find it, use the ping command in a Command Prompt. Type in:

ping stackoverflow.com

into the command prompt window and you’ll see stackoverflow's numerical IP address. Now use that IP into your host file

104.16.36.249 google.com

yay now google is serving stackoverflow :)

IntelliJ does not show project folders

When importing your project/module be sure to check these two boxes:

enter image description here

AngularJS ng-if with multiple conditions

Sure you can. Something like:

HTML

<div ng-controller="fessCntrl">    
     <label ng-repeat="(key,val) in list">
       <input type="radio" name="localityTypeRadio" ng-model="$parent.localityTypeRadio" ng-value="key" />{{key}}
         <div ng-if="key == 'City' || key == 'County'">
             <pre>City or County !!! {{$parent.localityTypeRadio}}</pre>
         </div>
         <div ng-if="key == 'Town'">
             <pre>Town!!! {{$parent.localityTypeRadio}}</pre>
         </div>        
      </label>
</div>

JS

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

fessmodule.controller('fessCntrl', function ($scope) {

    $scope.list = {
        City: [{name: "cityA"}, {name: "cityB"}],
        County: [{ name: "countyA"}, {name: "countyB"}],
        Town: [{ name: "townA"}, {name: "townB"}]
      };

    $scope.localityTypeRadio = 'City';
});

fessmodule.$inject = ['$scope'];

Demo Fiddle

HTML form submit to PHP script

<form method="POST" action="chk_kw.php">
    <select name="website_string"> 
        <option selected="selected"></option>
        <option value="abc">abc</option>
        <option value="def">def</option>
        <option value="hij">hij</option>   
    </select>
    <input type="submit">
</form>


  • As your form gets more complex, you can a quick check at top of your php script using print_r($_POST);, it'll show what's being submitted an the respective element name.
  • To get the submitted value of the element in question do:

    $website_string = $_POST['website_string'];

How to allow only integers in a textbox?

You can use client-side validation:

<asp:textbox onkeydown="return (!(event.keyCode>=65) && event.keyCode!=32);" />

Angular 2 declaring an array of objects

Another approach that is especially useful if you want to store data coming from an external API or a DB would be this:

  1. Create a class that represent your data model

    export class Data{
        private id:number;
        private text: string;
    
        constructor(id,text) {
            this.id = id;
            this.text = text;
        }
    
  2. In your component class you create an empty array of type Data and populate this array whenever you get a response from API or whatever data source you are using

    export class AppComponent {
        private search_key: string;
        private dataList: Data[] = [];
    
        getWikiData() {
           this.httpService.getDataFromAPI()
            .subscribe(data => {
              this.parseData(data);
            });
         }
    
        parseData(jsonData: string) {
        //considering you get your data in json arrays
        for (let i = 0; i < jsonData[1].length; i++) {
             const data = new WikiData(jsonData[1][i], jsonData[2][i]);
             this.wikiData.push(data);
        }
      }
    }
    

Why is php not running?

One big gotcha is that PHP is disabled in user home directories by default, so if you are testing from ~/public_html it doesn't work. Check /etc/apache2/mods-enabled/php5.conf

# Running PHP scripts in user directories is disabled by default
# 
# To re-enable PHP in user directories comment the following lines
# (from <IfModule ...> to </IfModule>.) Do NOT set it to On as it
# prevents .htaccess files from disabling it.
#<IfModule mod_userdir.c>
#    <Directory /home/*/public_html>
#        php_admin_flag engine Off
#    </Directory>
#</IfModule>

Other than that installing in Ubuntu is real easy, as all the stuff you used to have to put in httpd.conf is done automatically.

How can I find the link URL by link text with XPath?

if you are using html agility pack use getattributeValue:

$doc2.DocumentNode.SelectNodes("//div[@class='className']/div[@class='InternalClass']/a[@class='InternalClass']").GetAttributeValue("href","")

Trigger change event of dropdown

Try this:

$('#id').change();

Works for me.

On one line together with setting the value: $('#id').val(16).change();

How to change link color (Bootstrap)

You can use .text-reset class to reset the color from default blue to anything you want. Hopefully this is helpful.

Source: https://getbootstrap.com/docs/4.5/utilities/text/#reset-color

popup form using html/javascript/css

There are plenty available. Try using Modal windows of Jquery or DHTML would do good. Put the content in your div or Change your content in div dynamically and show it to the user. It won't be a popup but a modal window.
Jquery's Thickbox would clear your problem.

How to update a value, given a key in a hashmap?

Does the hash exist (with 0 as the value) or is it "put" to the map on the first increment? If it is "put" on the first increment, the code should look like:

if (hashmap.containsKey(key)) {
    hashmap.put(key, hashmap.get(key)+1);
} else { 
    hashmap.put(key,1);
}

The preferred way of creating a new element with jQuery

Much more expressive way,

jQuery('<div/>', {
    "id": 'foo',
    "name": 'mainDiv',
    "class": 'wrapper',
    "click": function() {
      jQuery(this).toggleClass("test");
    }}).appendTo('selector');

Reference: Docs

How do I compare version numbers in Python?

What's wrong with transforming the version string into a tuple and going from there? Seems elegant enough for me

>>> (2,3,1) < (10,1,1)
True
>>> (2,3,1) < (10,1,1,1)
True
>>> (2,3,1,10) < (10,1,1,1)
True
>>> (10,3,1,10) < (10,1,1,1)
False
>>> (10,3,1,10) < (10,4,1,1)
True

@kindall's solution is a quick example of how good the code would look.

How to search a list of tuples in Python

Supposing the list may be long and the numbers may repeat, consider using the SortedList type from the Python sortedcontainers module. The SortedList type will automatically maintain the tuples in order by number and allow for fast searching.

For example:

from sortedcontainers import SortedList
sl = SortedList([(1,"juca"),(22,"james"),(53,"xuxa"),(44,"delicia")])

# Get the index of 53:

index = sl.bisect((53,))

# With the index, get the tuple:

tup = sl[index]

This will work a lot faster than the list comprehension suggestion by doing a binary search. The dictionary suggestion will be faster still but won't work if there could be duplicate numbers with different strings.

If there are duplicate numbers with different strings then you need to take one more step:

end = sl.bisect((53 + 1,))

results = sl[index:end]

By bisecting for 54, we will find the end index for our slice. This will be significantly faster on long lists as compared with the accepted answer.

Using comma as list separator with AngularJS

Just use Javascript's built-in join(separator) function for arrays:

<li ng-repeat="friend in friends">
  <b>{{friend.email.join(', ')}}</b>...
</li>

check if a number already exist in a list in python

You could probably use a set object instead. Just add numbers to the set. They inherently do not replicate.

How do include paths work in Visual Studio?

If you are only trying to change the include paths for a project and not for all solutions then in Visual Studio 2008 do this: Right-click on the name of the project in the Solution Navigator. From the popup menu select Properties. In the property pages dialog select Configuration Properties->C/C++/General. Click in the text box next to the "Additional Include Files" label and browse for the appropriate directory. Select OK.

What annoys me is that some of the answers to the original question asked do not apply to the version of Visual Studio that was mentioned.

How to resolve the error on 'react-native start'

I just got a similar error for the first time today. It appears in \node_modules\metro-config\src\defaults\blacklist.js, there is an invalid regular expression that needed changed. I changed the first expression under sharedBlacklist from:

var sharedBlacklist = [
  /node_modules[/\\]react[/\\]dist[/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

to:

var sharedBlacklist = [
  /node_modules[\/\\]react[\/\\]dist[\/\\].*/,
  /website\/node_modules\/.*/,
  /heapCapture\/bundle\.js/,
  /.*\/__tests__\/.*/
];

Parsing JSON object in PHP using json_decode

Seems like you forgot the ["value"] or ->value:

echo $data[0]->weather->weatherIconUrl[0]->value;

How to get base64 encoded data from html image

You can try following sample http://jsfiddle.net/xKJB8/3/

<img id="preview" src="http://www.gravatar.com/avatar/0e39d18b89822d1d9871e0d1bc839d06?s=128&d=identicon&r=PG">
<canvas id="myCanvas" />

var c = document.getElementById("myCanvas");
var ctx = c.getContext("2d");
var img = document.getElementById("preview");
ctx.drawImage(img, 10, 10);
alert(c.toDataURL());

How to remove all line breaks from a string

A linebreak in regex is \n, so your script would be

var test = 'this\nis\na\ntest\nwith\newlines';
console.log(test.replace(/\n/g, ' '));

How to add multiple jar files in classpath in linux

Say you have multiple jar files a.jar,b.jar and c.jar. To add them to classpath while compiling you need to do

$javac -cp .:a.jar:b.jar:c.jar HelloWorld.java

To run do

$java -cp .:a.jar:b.jar:c.jar HelloWorld

How to securely save username/password (local)?

If you are just going to verify/validate the entered user name and password, use the Rfc2898DerivedBytes class (also known as Password Based Key Derivation Function 2 or PBKDF2). This is more secure than using encryption like Triple DES or AES because there is no practical way to go from the result of RFC2898DerivedBytes back to the password. You can only go from a password to the result. See Is it ok to use SHA1 hash of password as a salt when deriving encryption key and IV from password string? for an example and discussion for .Net or String encrypt / decrypt with password c# Metro Style for WinRT/Metro.

If you are storing the password for reuse, such as supplying it to a third party, use the Windows Data Protection API (DPAPI). This uses operating system generated and protected keys and the Triple DES encryption algorithm to encrypt and decrypt information. This means your application does not have to worry about generating and protecting the encryption keys, a major concern when using cryptography.

In C#, use the System.Security.Cryptography.ProtectedData class. For example, to encrypt a piece of data, use ProtectedData.Protect():

// Data to protect. Convert a string to a byte[] using Encoding.UTF8.GetBytes().
byte[] plaintext; 

// Generate additional entropy (will be used as the Initialization vector)
byte[] entropy = new byte[20];
using(RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
{
    rng.GetBytes(entropy);
}

byte[] ciphertext = ProtectedData.Protect(plaintext, entropy,
    DataProtectionScope.CurrentUser);

Store the entropy and ciphertext securely, such as in a file or registry key with permissions set so only the current user can read it. To get access to the original data, use ProtectedData.Unprotect():

byte[] plaintext= ProtectedData.Unprotect(ciphertext, entropy,
    DataProtectionScope.CurrentUser);

Note that there are additional security considerations. For example, avoid storing secrets like passwords as a string. Strings are immutable, being they cannot be notified in memory so someone looking at the application's memory or a memory dump may see the password. Use SecureString or a byte[] instead and remember to dispose or zero them as soon as the password is no longer needed.

Redis - Connect to Remote Server

Orabig is correct.

You can bind 10.0.2.15 in Ubuntu (VirtualBox) then do a port forwarding from host to guest Ubuntu.

in /etc/redis/redis.conf

bind 10.0.2.15

then, restart redis:

sudo systemctl restart redis

It shall work!

AngularJS : ng-click not working

For ng-click working properly you need define your controller after angularjs script binding and use it via $scope.

php create object without class

you can always use new stdClass(). Example code:

   $object = new stdClass();
   $object->property = 'Here we go';

   var_dump($object);
   /*
   outputs:

   object(stdClass)#2 (1) {
      ["property"]=>
      string(10) "Here we go"
    }
   */

Also as of PHP 5.4 you can get same output with:

$object = (object) ['property' => 'Here we go'];

How do I register a .NET DLL file in the GAC?

You can do that using the gacutil tool. In its simplest form:

gacutil /i yourdll.dll

You find the Visual Studio Command Prompt in the start menu under Programs -> Visual Studio -> Visual Studio Tools.

How to pass an array within a query string?

This works for me:

In link, to attribute has value:

to="/filter/arr?fruits=apple&fruits=banana"

Route can handle this:

path="/filter/:arr"

For Multiple arrays:

to="filter/arr?fruits=apple&fruits=banana&vegetables=potato&vegetables=onion"

Route stays same.

SCREENSHOT

enter image description here

Why does DEBUG=False setting make my django Static Files Access fail?

This is Exactly you must type on terminal to run your project without DEBUG = TRUE and then you see all assets (static) file is loading correctly On local server .

python manage.py runserver --insecure 

--insecure : it means you can run server without security mode

How to validate a form with multiple checkboxes to have atleast one checked

How about this:

$(document).ready(function() {
    $('#subscribeForm').submit(function() {
        var $fields = $(this).find('input[name="list"]:checked');
        if (!$fields.length) {
            alert('You must check at least one box!');
            return false; // The form will *not* submit
        }
    });
});

Ng-model does not update controller value

Have a look at this fiddle http://jsfiddle.net/ganarajpr/MSjqL/

I have ( I assume! ) done exactly what you were doing and it seems to be working. Can you check what is not working here for you?

How do you copy the contents of an array to a std::vector in C++ without looping?

Assuming you know how big the item in the vector are:

std::vector<int> myArray;
myArray.resize (item_count, 0);
memcpy (&myArray.front(), source, item_count * sizeof(int));

http://www.cppreference.com/wiki/stl/vector/start

In vb.net, how to get the column names from a datatable

You can loop through the columns collection of the datatable.

VB

Dim dt As New DataTable()
For Each column As DataColumn In dt.Columns
    Console.WriteLine(column.ColumnName)
Next

C#

DataTable dt = new DataTable();
foreach (DataColumn column in dt.Columns)
{
Console.WriteLine(column.ColumnName);
}

Hope this helps!

How to view file history in Git?

Of course, if you want something as close to TortoiseSVN as possible, you could just use TortoiseGit.

Response::json() - Laravel 5.1

although Response::json() is not getting popular of recent, that does not stop you and Me from using it. In fact you don't need any facade to use it,

instead of:

$response = Response::json($messages, 200);

Use this:

$response = \Response::json($messages, 200);

with the slash, you are sure good to go.

invalid conversion from 'const char*' to 'char*'

First of all this code snippet

char *addr=NULL;
strcpy(addr,retstring().c_str());

is invalid because you did not allocate memory where you are going to copy retstring().c_str().

As for the error message then it is clear enough. The type of expression data.str().c_str() is const char * but the third parameter of the function is declared as char *. You may not assign an object of type const char * to an object of type char *. Either the function should define the third parameter as const char * if it does not change the object pointed by the third parameter or you may not pass argument of type const char *.

Linq select objects in list where exists IN (A,B,C)

Try with Contains function;

Determines whether a sequence contains a specified element.

var allowedStatus = new[]{ "A", "B", "C" };
var filteredOrders = orders.Order.Where(o => allowedStatus.Contains(o.StatusCode));

No MediaTypeFormatter is available to read an object of type 'String' from content with media type 'text/plain'

Or you can just create your own MediaTypeFormatter. I use this for text/html. If you add text/plain to it, it'll work for you too:

public class TextMediaTypeFormatter : MediaTypeFormatter
{
    public TextMediaTypeFormatter()
    {
        SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/html"));
    }

    public override Task<object> ReadFromStreamAsync(Type type, Stream readStream, HttpContent content, IFormatterLogger formatterLogger)
    {
        return ReadFromStreamAsync(type, readStream, content, formatterLogger, CancellationToken.None);
    }

    public override async Task<object> ReadFromStreamAsync(Type type, Stream readStream, HttpContent content, IFormatterLogger formatterLogger, CancellationToken cancellationToken)
    {
        using (var streamReader = new StreamReader(readStream))
        {
            return await streamReader.ReadToEndAsync();
        }
    }

    public override bool CanReadType(Type type)
    {
        return type == typeof(string);
    }

    public override bool CanWriteType(Type type)
    {
        return false;
    }
}

Finally you have to assign this to the HttpMethodContext.ResponseFormatter property.

Multiline strings in VB.NET

I used this variant:

     Dim query As String = <![CDATA[
        SELECT 
            a.QuestionID
        FROM 
            CR_Answers a

        INNER JOIN 
            CR_Class c ON c.ClassID = a.ClassID
        INNER JOIN
            CR_Questions q ON q.QuestionID = a.QuestionID
        WHERE 
            a.CourseID = 1
        AND 
            c.ActionPlan = 1
        AND q.Q_Year = '11/12'
        AND q.Q_Term <= (SELECT CurrentTerm FROM CR_Current_Term)
    ]]>.Value()

it allows < > in the string

Bootstrap visible and hidden classes not working properly

As of today November 2017
Bootstrap v4 - beta

Responsive utilities

All @screen- variables have been removed in v4.0.0. Use the media-breakpoint-up(), media-breakpoint-down(), or media-breakpoint-only() Sass mixins or the $grid-breakpoints Sass map instead.

Removed from v3: .hidden-xs .hidden-sm .hidden-md .hidden-lg .visible-xs-block .visible-xs-inline .visible-xs-inline-block .visible-sm-block .visible-sm-inline .visible-sm-inline-block .visible-md-block .visible-md-inline .visible-md-inline-block .visible-lg-block .visible-lg-inline .visible-lg-inline-block

Removed from v4 alphas: .hidden-xs-up .hidden-xs-down .hidden-sm-up .hidden-sm-down .hidden-md-up .hidden-md-down .hidden-lg-up .hidden-lg-down

https://getbootstrap.com/docs/4.0/migration/#responsive-utilities

Calculating the position of points in a circle

For the sake of completion, what you describe as "position of points around a central point(assuming they're all equidistant from the center)" is nothing but "Polar Coordinates". And you are asking for way to Convert between polar and Cartesian coordinates which is given as x = r*cos(t), y = r*sin(t).

SQL - ORDER BY 'datetime' DESC

  1. use single quotes for strings
  2. do NOT put single quotes around table names(use ` instead)
  3. do NOT put single quotes around numbers (you can, but it's harder to read)
  4. do NOT put AND between ORDER BY and LIMIT
  5. do NOT put = between ORDER BY, LIMIT keywords and condition

So you query will look like:

SELECT post_datetime 
FROM post 
WHERE type = 'published' 
ORDER BY post_datetime DESC 
LIMIT 3

Conditional WHERE clause in SQL Server

Often when you use conditional WHERE clauses you end upp with a vastly inefficient query, which is noticeable for large datasets where indexes are used. A great way to optimize the query for different values of your parameter is to make a different execution plan for each value of the parameter. You can achieve this using OPTION (RECOMPILE).

In this example it would probably not make much difference, but say the condition should only be used in one of two cases, then you could notice a big impact.

In this example:

WHERE 
    DateDropped = 0
    AND (
    (ISNULL(@JobsOnHold, 0) = 1 AND DateAppr >= 0) 
    OR 
    (ISNULL(@JobsOnHold, 0) <> 1 AND DateAppr <> 0)
    )
OPTION (RECOMPILE)

Source Parameter Sniffing, Embedding, and the RECOMPILE Options

CSS full screen div with text in the middle

There is no pure CSS solution to this classical problem.

If you want to achieve this, you have two solutions:

  • Using a table (ugly, non semantic, but the only way to vertically align things that are not a single line of text)
  • Listening to window.resize and absolute positionning

EDIT: when I say that there is no solution, I take as an hypothesis that you don't know in advance the size of the block to center. If you know it, paislee's solution is very good

linq where list contains any in list

You can use a Contains query for this:

var movies = _db.Movies.Where(p => p.Genres.Any(x => listOfGenres.Contains(x));

ASP.NET MVC: Custom Validation by DataAnnotation

Self validated model

Your model should implement an interface IValidatableObject. Put your validation code in Validate method:

public class MyModel : IValidatableObject
{
    public string Title { get; set; }
    public string Description { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
    {
        if (Title == null)
            yield return new ValidationResult("*", new [] { nameof(Title) });

        if (Description == null)
            yield return new ValidationResult("*", new [] { nameof(Description) });
    }
}

Please notice: this is a server-side validation. It doesn't work on client-side. You validation will be performed only after form submission.

Binding List<T> to DataGridView in WinForm

This isn't exactly the issue I had, but if anyone is looking to convert a BindingList of any type to List of the same type, then this is how it is done:

var list = bindingList.ToDynamicList();

Also, if you're assigning BindingLists of dynamic types to a DataGridView.DataSource, then make sure you declare it first as IBindingList so the above works.

Limit number of characters allowed in form input text field

Add the following to the header:

<script language="javascript" type="text/javascript">
function limitText(limitField, limitNum) {
    if (limitField.value.length > limitNum) {
        limitField.value = limitField.value.substring(0, limitNum);
    }
}
</script>

    <input type="text" id="sessionNo" name="sessionNum" onKeyDown="limitText(this,5);" 
onKeyUp="limitText(this,5);"" />

How to see full query from SHOW PROCESSLIST

If one want to keep getting updated processes (on the example, 2 seconds) on a shell session without having to manually interact with it use:

watch -n 2 'mysql -h 127.0.0.1 -P 3306 -u some_user -psome_pass some_database -e "show full processlist;"'

The only bad thing about the show [full] processlist is that you can't filter the output result. On the other hand, issuing the SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST open possibilities to remove from the output anything you don't want to see:

SELECT * from INFORMATION_SCHEMA.PROCESSLIST
WHERE DB = 'somedatabase'
AND COMMAND <> 'Sleep'
AND HOST NOT LIKE '10.164.25.133%' \G

I don't have "Dynamic Web Project" option in Eclipse new Project wizard

Go to Eclipse --> Help

and click--->Install new software

then you can see a window ...There a click add

Then put below url in url box: http://download.eclipse.org/webtools/repository/juno/

i am having juno

if u have any other means put that name . then click ok.

How do I find ' % ' with the LIKE operator in SQL Server?

Try this:

declare @var char(3)
set @var='[%]'
select Address from Accomodation where Address like '%'+@var+'%' 

You must use [] cancels the effect of wildcard, so you read % as a normal character, idem about character _

Explain the "setUp" and "tearDown" Python methods used in test cases

In general you add all prerequisite steps to setUp and all clean-up steps to tearDown.

You can read more with examples here.

When a setUp() method is defined, the test runner will run that method prior to each test. Likewise, if a tearDown() method is defined, the test runner will invoke that method after each test.

For example you have a test that requires items to exist, or certain state - so you put these actions(creating object instances, initializing db, preparing rules and so on) into the setUp.

Also as you know each test should stop in the place where it was started - this means that we have to restore app state to it's initial state - e.g close files, connections, removing newly created items, calling transactions callback and so on - all these steps are to be included into the tearDown.

So the idea is that test itself should contain only actions that to be performed on the test object to get the result, while setUp and tearDown are the methods to help you to leave your test code clean and flexible.

You can create a setUp and tearDown for a bunch of tests and define them in a parent class - so it would be easy for you to support such tests and update common preparations and clean ups.

If you are looking for an easy example please use the following link with example

Get all variables sent with POST?

you should be able to access them from $_POST variable:

foreach ($_POST as $param_name => $param_val) {
    echo "Param: $param_name; Value: $param_val<br />\n";
}

How do you fadeIn and animate at the same time?

Another way to do simultaneous animations if you want to call them separately (eg. from different code) is to use queue. Again, as with Tinister's answer you would have to use animate for this and not fadeIn:

$('.tooltip').css('opacity', 0);
$('.tooltip').show();
...

$('.tooltip').animate({opacity: 1}, {queue: false, duration: 'slow'});
$('.tooltip').animate({ top: "-10px" }, 'slow');

Returning null in a method whose signature says return int?

Change your return type to java.lang.Integer . This way you can safely return null

Examples of GoF Design Patterns in Java's core libraries

  1. Observer pattern throughout whole swing (Observable, Observer)
  2. MVC also in swing
  3. Adapter pattern: InputStreamReader and OutputStreamWriter NOTE: ContainerAdapter, ComponentAdapter, FocusAdapter, KeyAdapter, MouseAdapter are not adapters; they are actually Null Objects. Poor naming choice by Sun.
  4. Decorator pattern (BufferedInputStream can decorate other streams such as FilterInputStream)
  5. AbstractFactory Pattern for the AWT Toolkit and the Swing pluggable look-and-feel classes
  6. java.lang.Runtime#getRuntime() is Singleton
  7. ButtonGroup for Mediator pattern
  8. Action, AbstractAction may be used for different visual representations to execute same code -> Command pattern
  9. Interned Strings or CellRender in JTable for Flyweight Pattern (Also think about various pools - Thread pools, connection pools, EJB object pools - Flyweight is really about management of shared resources)
  10. The Java 1.0 event model is an example of Chain of Responsibility, as are Servlet Filters.
  11. Iterator pattern in Collections Framework
  12. Nested containers in AWT/Swing use the Composite pattern
  13. Layout Managers in AWT/Swing are an example of Strategy

and many more I guess

initialize a vector to zeros C++/C++11

Initializing a vector having struct, class or Union can be done this way

std::vector<SomeStruct> someStructVect(length);
memset(someStructVect.data(), 0, sizeof(SomeStruct)*length);

Why is "throws Exception" necessary when calling a function?

The throws Exception declaration is an automated way of keeping track of methods that might throw an exception for anticipated but unavoidable reasons. The declaration is typically specific about the type or types of exceptions that may be thrown such as throws IOException or throws IOException, MyException.

We all have or will eventually write code that stops unexpectedly and reports an exception due to something we did not anticipate before running the program, like division by zero or index out of bounds. Since the errors were not expected by the method, they could not be "caught" and handled with a try catch clause. Any unsuspecting users of the method would also not know of this possibility and their programs would also stop.

When the programmer knows certain types of errors may occur but would like to handle these exceptions outside of the method, the method can "throw" one or more types of exceptions to the calling method instead of handling them. If the programmer did not declare that the method (might) throw an exception (or if Java did not have the ability to declare it), the compiler could not know and it would be up to the future user of the method to know about, catch and handle any exceptions the method might throw. Since programs can have many layers of methods written by many different programs, it becomes difficult (impossible) to keep track of which methods might throw exceptions.

Even though Java has the ability to declare exceptions, you can still write a new method with unhandled and undeclared exceptions, and Java will compile it and you can run it and hope for the best. What Java won't let you do is compile your new method if it uses a method that has been declared as throwing exception(s), unless you either handle the declared exception(s) in your method or declare your method as throwing the same exception(s) or if there are multiple exceptions, you can handle some and throw the rest.

When a programmer declares that the method throws a specific type of exception, it is just an automated way of warning other programmers using the method that an exception is possible. The programmer can then decide to handled the exception or pass on the warning by declaring the calling method as also throwing the same exception. Since the compiler has been warned the exception is possible in this new method, it can automatically check if future callers of the new method handle the exception or declare it and enforcing one or the other to happen.

The nice thing about this type of solution is that when the compiler reports Error: Unhandled exception type java.io.IOException it gives the file and line number of the method that was declared to throw the exception. You can then choose to simply pass the buck and declare your method also "throws IOException". This can be done all the way up to main method where it would then cause the program to stop and report the exception to the user. However, it is better to catch the exception and deal with it in a nice way such as explaining to the user what has happened and how to fix it. When a method does catch and handle the exception, it no longer has to declare the exception. The buck stops there so to speak.

How to prevent 'query timeout expired'? (SQLNCLI11 error '80040e31')

Turns out that the post (or rather the whole table) was locked by the very same connection that I tried to update the post with.

I had a opened record set of the post that was created by:

Set RecSet = Conn.Execute()

This type of recordset is supposed to be read-only and when I was using MS Access as database it did not lock anything. But apparently this type of record set did lock something on MS SQL Server 2012 because when I added these lines of code before executing the UPDATE SQL statement...

RecSet.Close
Set RecSet = Nothing

...everything worked just fine.

So bottom line is to be careful with opened record sets - even if they are read-only they could lock your table from updates.

C# Convert string from UTF-8 to ISO-8859-1 (Latin1) H

Seems bit strange code. To get string from Utf8 byte stream all you need to do is:

string str = Encoding.UTF8.GetString(utf8ByteArray);

If you need to save iso-8859-1 byte stream to somewhere then just use: additional line of code for previous:

byte[] iso88591data = Encoding.GetEncoding("ISO-8859-1").GetBytes(str);

SSL error : routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed

The server certificate is invalid, either because it is signed by an invalid CA (internal CA, self signed,...), doesn't match the server's name or because it is expired.

Either way, you need to find how to tell to the Python library that you are using that it must not stop at an invalid certificate if you really want to download files from this server.

Convert Rtf to HTML

You can try to upload it to google docs, and download it as HTML.

How do you synchronise projects to GitHub with Android Studio?

For Android Studio 0.8.9: VCS --> Import into version contraol --> Share project on Github. It doesn't give you option to share in a specific repository or at least I couldn't find (my limitation!).

You can add your github info here: File --> Settings --> Version COntraol --> Github.

How to get progress from XMLHttpRequest

The only way to do that with pure javascript is to implement some kind of polling mechanism. You will need to send ajax requests at fixed intervals (each 5 seconds for example) to get the number of bytes received by the server.

A more efficient way would be to use flash. The flex component FileReference dispatchs periodically a 'progress' event holding the number of bytes already uploaded. If you need to stick with javascript, bridges are available between actionscript and javascript. The good news is that this work has been already done for you :)

swfupload

This library allows to register a javascript handler on the flash progress event.

This solution has the hudge advantage of not requiring aditionnal resources on the server side.

How do I auto size columns through the Excel interop objects?

Add this at your TODO point:

aRange.Columns.AutoFit();

java.math.BigInteger cannot be cast to java.lang.Long

Are you sure dynamics is a List<Long> and not List<BigInteger> ?

If dynamics is a List<Long> you don't need to do a cast to (Long)

Bootstrap 3 Multi-column within a single ul not floating properly

you are thinking too much... Take a look at this [i think this is what you wanted - if not let me know]

http://www.bootply.com/118886

css

.even{background: red; color:white;}
.odd{background: darkred; color:white;}

html

<div class="container">
  <ul class="list-unstyled">
    <li class="col-md-6 odd">Dumby Content</li>
    <li class="col-md-6 odd">Dumby Content</li>
    <li class="col-md-6 even">Dumby Content</li>
    <li class="col-md-6 even">Dumby Content</li>
    <li class="col-md-6 odd">Dumby Content</li>
    <li class="col-md-6 odd">Dumby Content</li>
  </ul>
</div>

List file names based on a filename pattern and file content?

grep LMN20113456 LMN2011*

or if you want to search recursively through subdirectories:

find . -type f -name 'LMN2011*' -exec grep LMN20113456 {} \;

What is the easiest way to install BLAS and LAPACK for scipy?

For windows: Best is to use pre-compiled package available from this site: http://www.lfd.uci.edu/%7Egohlke/pythonlibs/#scipy

CodeIgniter: Unable to connect to your database server using the provided settings Error Message

If you used this to secure your server: http://www.thonky.com/how-to/prevent-base-64-decode-hack/

And then got the error: Code Igniter needs mysql_pconnect() in order to run.

I figured it out once I realized all the Code Igniter websites on the server were broken, so it wasn't a localized connection issue.

Error:java: invalid source release: 8 in Intellij. What does it mean?

I checked all above said project version, module version, project bytecode version, target bytecode version settings in IntelliJ Idea, but all were the same as I scratched.

I face this error Error:java: invalid source release: 1.8 in IntelliJ Idea 2017.2.6 because I upgraded the dependency version Maven pom file, which(dependency) were supposed to build for JDK 1.8 application and I were building my application on and with maven compiler source and target JDK 1.7.

Hence I again downgrade the dependency version to earlier one in Maven pom, and the error gone after project Rebuild Module 'xyz_project'.

Disable cross domain web security in Firefox

I have not been able to find a Firefox option equivalent of --disable-web-security or an addon that does that for me. I really needed it for some testing scenarios where modifying the web server was not possible. What did help was to use Fiddler to auto-modify web responses so that they have the correct headers and CORS is no longer an issue.

The steps are:

  1. Open fiddler.

  2. If on https go to menu Tools -> Options -> Https and tick the Capture & Decrypt https options

  3. Go to menu Rules -> Customize rules. Modify the OnBeforeResponseFunction so that it looks like the following, then save:

     static function OnBeforeResponse(oSession: Session) {
        //....
        oSession.oResponse.headers.Remove("Access-Control-Allow-Origin");
        oSession.oResponse.headers.Add("Access-Control-Allow-Origin", "*");
        //...
     }
    

    This will make every web response to have the Access-Control-Allow-Origin: * header.

  4. This still won't work as the OPTIONS preflight will pass through and cause the request to block before our above rule gets the chance to modify the headers. So to fix this, in the fiddler main window, on the right hand side there's an AutoResponder tab. Add a new rule and response: METHOD:OPTIONS https://yoursite.com/ with auto response: *CORSPreflightAllow and tick the boxes: "Enable Rules" and "Unmatched requests passthrough".

See picture below for reference:

enter image description here

SQL Server SELECT INTO @variable?

you can do this:

SELECT 
    CustomerId, 
    FirstName, 
    LastName, 
    Email
INTO #tempCustomer 
FROM 
    Customer
WHERE 
    CustomerId = @CustomerId

then later

SELECT CustomerId FROM #tempCustomer

you doesn't need to declare the structure of #tempCustomer

Most efficient way to concatenate strings?

Following may be one more alternate solution to concatenate multiple strings.

String str1 = "sometext";
string str2 = "some other text";

string afterConcate = $"{str1}{str2}";

string interpolation

Do subclasses inherit private fields?

It depends on your definition of "inherit". Does the subclass still have the fields in memory? Definitely. Can it access them directly? No. It's just subtleties of the definition; the point is to understand what's really happening.

CRON command to run URL address every 5 minutes

Based on the comments try

*/5 * * * * wget http://example.com/check

[Edit: 10 Apr 2017]

This answer still seems to be getting a few hits so I thought I'd add a link to a new page I stumbled across which may help create cron commands: https://crontab.guru

jQuery CSS Opacity

Try with this :

jQuery('#main').css({ opacity: 0.6 });

Update Git branches from master

git rebase master is the proper way to do this. Merging would mean a commit would be created for the merge, while rebasing would not.

JavaFX "Location is required." even though it is in the same package

The root directory for the loader is in the 'resources' folder for a maven project. So if you have src/main/java then the fxml file path should start from: src/main/resources

https://maven.apache.org/guides/introduction/introduction-to-the-standard-directory-layout.html

How to check if a radiobutton is checked in a radiogroup in Android?

try to use this

<RadioGroup
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"       
    android:orientation="horizontal"
>    
    <RadioButton
        android:id="@+id/standard_delivery"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/Standard_delivery"
        android:checked="true"
        android:layout_marginTop="4dp"
        android:layout_marginLeft="15dp"
        android:textSize="12dp"
        android:onClick="onRadioButtonClicked"   
    />

    <RadioButton
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/Midnight_delivery"
        android:checked="false"
        android:layout_marginRight="15dp"
        android:layout_marginTop="4dp"
        android:textSize="12dp"
        android:onClick="onRadioButtonClicked"
        android:id="@+id/midnight_delivery"
    />    
</RadioGroup>

this is java class

public void onRadioButtonClicked(View view) {
        // Is the button now checked?
        boolean checked = ((RadioButton) view).isChecked();

        // Check which radio button was clicked
        switch(view.getId()) {
            case R.id.standard_delivery:
                if (checked)
                    Toast.makeText(DishActivity.this," standard delivery",Toast.LENGTH_LONG).show();
                    break;
            case R.id.midnight_delivery:
                if (checked)
                    Toast.makeText(DishActivity.this," midnight delivery",Toast.LENGTH_LONG).show();
                    break;
        }
    }

<> And Not In VB.NET

If you need to know if the variable exists use Is/IsNot Nothing.

Using <> requires that the variable you're evaluating have the "<>" operator defined. Check out

 Dim b As HttpContext
 If b <> Nothing Then
    ...
 End If

and the resultant error

Error   1   Operator '<>' is not defined for types 'System.Web.HttpContext' and 'System.Web.HttpContext'.   

How do I kill an Activity when the Back button is pressed?

Well, if you study the structure of how the application life-cycle works,here , then you'll come to know that onPause() is called when another activity gains focus, and onStop() is called when the activity is no longer visible.

From what I have learned yet, you can call finish() only from the activity which is active and/or has the focus. If you're calling finish() from the onPause() method that means you're calling it when the activity is no longer active. thus an exception is thrown.

When you're calling finish() from onStop() then the activity is being sent to background, thus will no longer be visible, then this exception.

When you press the back button, onStop() is called.

Most probably, Android will automatically do for you what you are currently wanting to do.

iPhone hide Navigation Bar only on first page

If what you want is to hide the navigation bar completely in the controller, a much cleaner solution is to, in the root controller, have something like:

@implementation MainViewController
- (void)viewDidLoad {
    self.navigationController.navigationBarHidden=YES;
    //...extra code on view load  
}

When you push a child view in the controller, the Navigation Bar will remain hidden; if you want to display it just in the child, you'll add the code for displaying it(self.navigationController.navigationBarHidden=NO;) in the viewWillAppear callback, and similarly the code for hiding it on viewWillDisappear

How can I find the version of the Fedora I use?

The proposed standard file is /etc/os-release. See http://www.freedesktop.org/software/systemd/man/os-release.html

You can execute something like:

$ source /etc/os-release
$ echo $ID
fedora
$ echo $VERSION_ID
17
$ echo $VERSION
17 (Beefy Miracle)

jQuery click anywhere in the page except on 1 div

try this

 $('html').click(function() {
 //your stuf
 });

 $('#menucontainer').click(function(event){
     event.stopPropagation();
 });

you can also use the outside events

Run a shell script with an html button

This is really just an expansion of BBB's answer which lead to to get my experiment working.

This script will simply create a file /tmp/testfile when you click on the button that says "Open Script".

This requires 3 files.

  1. The actual HTML Website with a button.
  2. A php script which executes the script
  3. A Script

The File Tree:

root@test:/var/www/html# tree testscript/
testscript/
+-- index.html
+-- testexec.php
+-- test.sh

1. The main WebPage:

root@test:/var/www/html# cat testscript/index.html
<form action="/testscript/testexec.php">
    <input type="submit" value="Open Script">
</form>

2. The PHP Page that runs the script and redirects back to the main page:

root@test:/var/www/html# cat testscript/testexec.php
<?php
shell_exec("/var/www/html/testscript/test.sh");
header('Location: http://192.168.1.222/testscript/index.html?success=true');
?>

3. The Script :

root@test:/var/www/html# cat testscript/test.sh

#!/bin/bash

touch /tmp/testfile

Importing text file into excel sheet

you can write .WorkbookConnection.Delete after .Refresh BackgroundQuery:=False this will delete text file external connection.

How do I iterate through each element in an n-dimensional matrix in MATLAB?

One other trick is to use ind2sub and sub2ind. In conjunction with numel and size, this can let you do stuff like the following, which creates an N-dimensional array, and then sets all the elements on the "diagonal" to be 1.

d = zeros( 3, 4, 5, 6 ); % Let's pretend this is a user input
nel = numel( d );
sz = size( d );
szargs = cell( 1, ndims( d ) ); % We'll use this with ind2sub in the loop
for ii=1:nel
    [ szargs{:} ] = ind2sub( sz, ii ); % Convert linear index back to subscripts
    if all( [szargs{2:end}] == szargs{1} ) % On the diagonal?
        d( ii ) = 1;
    end
end

jQuery Datepicker onchange event issue

DatePicker selected value change event code below

/* HTML Part */
<p>Date: <input type="text" id="datepicker"></p>

/* jQuery Part */
$("#datepicker").change(function() {
                selectedDate= $('#datepicker').datepicker({ dateFormat: 'yy-mm-dd' }).val();
                alert(selectedDate);        
            });

Read/Parse text file line by line in VBA

I find the FileSystemObject with a TxtStream the easiest way to read files

Dim fso As FileSystemObject: Set fso = New FileSystemObject
Set txtStream = fso.OpenTextFile(filePath, ForReading, False)

Then with this txtStream object you have all sorts of tools which intellisense picks up (unlike using the FreeFile() method) so there is less guesswork. Plus you don' have to assign a FreeFile and hope it is actually still free since when you assigned it.

You can read a file like:

Do While Not txtStream.AtEndOfStream
    txtStream.ReadLine
Loop
txtStream.Close

NOTE: This requires a reference to Microsoft Scripting Runtime.

how to set JAVA_OPTS for Tomcat in Windows?

Apparently the correct form is without the ""

As in

set JAVA_OPTS=-Xms512M -Xmx1024M

UITableView - change section header color

Setting the background color on UITableViewHeaderFooterView has been deprecated. Please use contentView.backgroundColor instead.

How to set an iframe src attribute from a variable in AngularJS

It is the $sce service that blocks URLs with external domains, it is a service that provides Strict Contextual Escaping services to AngularJS, to prevent security vulnerabilities such as XSS, clickjacking, etc. it's enabled by default in Angular 1.2.

You can disable it completely, but it's not recommended

angular.module('myAppWithSceDisabledmyApp', [])
   .config(function($sceProvider) {
       $sceProvider.enabled(false);
   });

for more info https://docs.angularjs.org/api/ng/service/$sce

Android: Force EditText to remove focus?

Remove focus but remain focusable:

editText.setFocusableInTouchMode(false);
editText.setFocusable(false);
editText.setFocusableInTouchMode(true);
editText.setFocusable(true);

EditText will lose focus, but can gain it again on a new touch event.

XML Schema Validation : Cannot find the declaration of element

The targetNamespace of your XML Schema does not match the namespace of the Root element (dot in Test.Namespace vs. comma in Test,Namespace)

Once you make the above agree, you have to consider that your element2 has an attribute order that is not in your XSD.

Should I use the Reply-To header when sending emails as a service to others?

Here is worked for me:

Subject: SomeSubject
From:Company B (me)
Reply-to:Company A
To:Company A's customers

Safe String to BigDecimal conversion

I needed a solution to convert a String to a BigDecimal without knowing the locale and being locale-independent. I couldn't find any standard solution for this problem so i wrote my own helper method. May be it helps anybody else too:

Update: Warning! This helper method works only for decimal numbers, so numbers which always have a decimal point! Otherwise the helper method could deliver a wrong result for numbers between 1000 and 999999 (plus/minus). Thanks to bezmax for his great input!

static final String EMPTY = "";
static final String POINT = '.';
static final String COMMA = ',';
static final String POINT_AS_STRING = ".";
static final String COMMA_AS_STRING = ",";

/**
     * Converts a String to a BigDecimal.
     *     if there is more than 1 '.', the points are interpreted as thousand-separator and will be removed for conversion
     *     if there is more than 1 ',', the commas are interpreted as thousand-separator and will be removed for conversion
     *  the last '.' or ',' will be interpreted as the separator for the decimal places
     *  () or - in front or in the end will be interpreted as negative number
     *
     * @param value
     * @return The BigDecimal expression of the given string
     */
    public static BigDecimal toBigDecimal(final String value) {
        if (value != null){
            boolean negativeNumber = false;

            if (value.containts("(") && value.contains(")"))
               negativeNumber = true;
            if (value.endsWith("-") || value.startsWith("-"))
               negativeNumber = true;

            String parsedValue = value.replaceAll("[^0-9\\,\\.]", EMPTY);

            if (negativeNumber)
               parsedValue = "-" + parsedValue;

            int lastPointPosition = parsedValue.lastIndexOf(POINT);
            int lastCommaPosition = parsedValue.lastIndexOf(COMMA);

            //handle '1423' case, just a simple number
            if (lastPointPosition == -1 && lastCommaPosition == -1)
                return new BigDecimal(parsedValue);
            //handle '45.3' and '4.550.000' case, only points are in the given String
            if (lastPointPosition > -1 && lastCommaPosition == -1){
                int firstPointPosition = parsedValue.indexOf(POINT);
                if (firstPointPosition != lastPointPosition)
                    return new BigDecimal(parsedValue.replace(POINT_AS_STRING, EMPTY));
                else
                    return new BigDecimal(parsedValue);
            }
            //handle '45,3' and '4,550,000' case, only commas are in the given String
            if (lastPointPosition == -1 && lastCommaPosition > -1){
                int firstCommaPosition = parsedValue.indexOf(COMMA);
                if (firstCommaPosition != lastCommaPosition)
                    return new BigDecimal(parsedValue.replace(COMMA_AS_STRING, EMPTY));
                else
                    return new BigDecimal(parsedValue.replace(COMMA, POINT));
            }
            //handle '2.345,04' case, points are in front of commas
            if (lastPointPosition < lastCommaPosition){
                parsedValue = parsedValue.replace(POINT_AS_STRING, EMPTY);
                return new BigDecimal(parsedValue.replace(COMMA, POINT));
            }
            //handle '2,345.04' case, commas are in front of points
            if (lastCommaPosition < lastPointPosition){
                parsedValue = parsedValue.replace(COMMA_AS_STRING, EMPTY);
                return new BigDecimal(parsedValue);
            }
            throw new NumberFormatException("Unexpected number format. Cannot convert '" + value + "' to BigDecimal.");
        }
        return null;
    }

Of course i've tested the method:

@Test(dataProvider = "testBigDecimals")
    public void toBigDecimal_defaultLocaleTest(String stringValue, BigDecimal bigDecimalValue){
        BigDecimal convertedBigDecimal = DecimalHelper.toBigDecimal(stringValue);
        Assert.assertEquals(convertedBigDecimal, bigDecimalValue);
    }
    @DataProvider(name = "testBigDecimals")
    public static Object[][] bigDecimalConvertionTestValues() {
        return new Object[][] {
                {"5", new BigDecimal(5)},
                {"5,3", new BigDecimal("5.3")},
                {"5.3", new BigDecimal("5.3")},
                {"5.000,3", new BigDecimal("5000.3")},
                {"5.000.000,3", new BigDecimal("5000000.3")},
                {"5.000.000", new BigDecimal("5000000")},
                {"5,000.3", new BigDecimal("5000.3")},
                {"5,000,000.3", new BigDecimal("5000000.3")},
                {"5,000,000", new BigDecimal("5000000")},
                {"+5", new BigDecimal("5")},
                {"+5,3", new BigDecimal("5.3")},
                {"+5.3", new BigDecimal("5.3")},
                {"+5.000,3", new BigDecimal("5000.3")},
                {"+5.000.000,3", new BigDecimal("5000000.3")},
                {"+5.000.000", new BigDecimal("5000000")},
                {"+5,000.3", new BigDecimal("5000.3")},
                {"+5,000,000.3", new BigDecimal("5000000.3")},
                {"+5,000,000", new BigDecimal("5000000")},
                {"-5", new BigDecimal("-5")},
                {"-5,3", new BigDecimal("-5.3")},
                {"-5.3", new BigDecimal("-5.3")},
                {"-5.000,3", new BigDecimal("-5000.3")},
                {"-5.000.000,3", new BigDecimal("-5000000.3")},
                {"-5.000.000", new BigDecimal("-5000000")},
                {"-5,000.3", new BigDecimal("-5000.3")},
                {"-5,000,000.3", new BigDecimal("-5000000.3")},
                {"-5,000,000", new BigDecimal("-5000000")},
                {null, null}
        };
    }

comparing two strings in SQL Server

There is no direct string compare function in SQL Server

CASE
  WHEN str1 = str2 THEN 0
  WHEN str1 < str2 THEN -1
  WHEN str1 > str2 THEN 1
  ELSE NULL --one of the strings is NULL so won't compare (added on edit)
END

Notes

  • you can wraps this via a UDF using CREATE FUNCTION etc
  • you may need NULL handling (in my code above, any NULL will report 1)
  • str1 and str2 will be column names or @variables

Uploading multiple files using formData()

The way to go with javascript:

var data = new FormData();

$.each($("input[type='file']")[0].files, function(i, file) {
    data.append('file', file);
});

$.ajax({
    type: 'POST',
    url: '/your/url',
    cache: false,
    contentType: false,
    processData: false,
    data : data,
    success: function(result){
        console.log(result);
    },
    error: function(err){
        console.log(err);
    }
})

If you call data.append('file', file) multiple times your request will contain an array of your files.

From MDN web docs:

"The append() method of the FormData interface appends a new value onto an existing key inside a FormData object, or adds the key if it does not already exist. The difference between FormData.set and append() is that if the specified key already exists, FormData.set will overwrite all existing values with the new one, whereas append() will append the new value onto the end of the existing set of values."

Myself using node.js and multipart handler middleware multer get the data as follows:

router.post('/trip/save', upload.array('file', 10), function(req, res){
    // Your array of files is in req.files
}

ERROR 2003 (HY000): Can't connect to MySQL server on '127.0.0.1' (111)

Try dont shut down iptables and open port 3306.

sudo iptables -A INPUT -i eth0 -p tcp -m tcp --dport 3306 -j ACCEPT

or sudo ufw allow 3306 if you use ufw.

check: netstat -lnp | grep mysql you should get sth like that:

cp        0      0 127.0.0.1:3306          0.0.0.0:*               LISTEN      2048/mysqld         
tcp6       0      0 :::33060                :::*                    LISTEN      2048/mysqld         
unix  2      [ ACC ]     STREAM     LISTENING     514961   2048/mysqld          /var/run/mysqld/mysqld.sock
unix  2      [ ACC ]     STREAM     LISTENING     514987   2048/mysqld          /var/run/mysqld/mysqlx.sock

if you have null then delete # before port = 3306 in cnf file.

Java, How to add library files in netbeans?

For Netbeans 2020 September version. JDK 11

(Suggesting this for Gradle project only)

1. create libs folder in src/main/java folder of the project

2. copy past all library jars in there

3. open build.gradle in files tab of project window in project's root

4. correct main class (mine is mainClassName = 'uz.ManipulatorIkrom')

5. and in dependencies add next string:

apply plugin: 'java' 
apply plugin: 'jacoco' 
apply plugin: 'application'
description = 'testing netbeans'
mainClassName = 'uz.ManipulatorIkrom' //4th step
repositories {
    jcenter()
}
dependencies {
    implementation fileTree(dir: 'src/main/java/libs', include: '*.jar') //5th step   
}

6. save, clean-build and then run the app

Functional style of Java 8's Optional.ifPresent and if-not-Present?

There isn't a great way to do it out of the box. If you want to be using your cleaner syntax on a regular basis, then you can create a utility class to help out:

public class OptionalEx {
    private boolean isPresent;

    private OptionalEx(boolean isPresent) {
        this.isPresent = isPresent;
    }

    public void orElse(Runnable runner) {
        if (!isPresent) {
            runner.run();
        }
    }

    public static <T> OptionalEx ifPresent(Optional<T> opt, Consumer<? super T> consumer) {
        if (opt.isPresent()) {
            consumer.accept(opt.get());
            return new OptionalEx(true);
        }
        return new OptionalEx(false);
    }
}

Then you can use a static import elsewhere to get syntax that is close to what you're after:

import static com.example.OptionalEx.ifPresent;

ifPresent(opt, x -> System.out.println("found " + x))
    .orElse(() -> System.out.println("NOT FOUND"));

String Concatenation in EL

Since Expression Language 3.0, it is valid to use += operator for string concatenation.

${(empty value)? "none" : value += " enabled"}  // valid as of EL 3.0

Quoting EL 3.0 Specification.

String Concatenation Operator

To evaluate

A += B 
  • Coerce A and B to String.
  • Return the concatenated string of A and B.

Capitalize only first character of string and leave others alone? (Rails)

Titleize will capitalise every word. This line feels hefty, but will guarantee that the only letter changed is the first one.

new_string = string.slice(0,1).capitalize + string.slice(1..-1)

Update:

irb(main):001:0> string = "i'm from New York..."
=> "i'm from New York..."
irb(main):002:0> new_string = string.slice(0,1).capitalize + string.slice(1..-1)
=> "I'm from New York..."

CSS3 Fade Effect

It's possible, use the structure below:

<li><a><span></span></a></li>
<li><a><span></span></a></li>

etc...

Where the <li> contains an <a> anchor tag that contains a span as shown above. Then insert the following css:

  • LI get position: relative;
  • Give <a> tag a height, width
  • Set <span> width & height to 100%, so that both <a> and <span> have same dimensions
  • Both <a> and <span> get position: relative;.
  • Assign the same background image to each element
  • <a> tag will have the 'OFF' background-position, and the <span> will have the 'ON' background-poisiton.
  • For 'OFF' state use opacity 0 for <span>
  • For 'ON' :hover state use opacity 1 for <span>
  • Set the -webkit or -moz transition on the <span> element

You'll have the ability to use the transition effect while still defaulting to the old background-position swap. Don't forget to insert IE alpha filter.

How to set up file permissions for Laravel?

I have installed laravel on EC2 instance and have spent 3 days to fix the permission error and at last fixed it. So I want to share this experience with other one.

  1. user problem When I logged in ec2 instance, my username is ec2-user and usergroup is ec2-user. And the website works under of httpd user: apache: apache so we should set the permission for apache.

  2. folder and file permission A. folder structure first, you should make sure that you have such folder structure like this under storage

    storage

    • framework
      • cache
      • sessions
      • views
    • logs The folder structure can be different according to the laravel version you use. my laravel version is 5.2 and you could find the appropriate structure according to your version.

B. permission At first, I see the instructions to set 777 under storage to remove file_put_contents: failed to open stream error. So i setup permission 777 to storage chmod -R 777 storage But the error was not fixed. here, you should consider one: who writes files to storage/ sessions and views. That is not ec2-user, but apache. Yes, right. "apache" user writes file (session file, compiled view file) to the session and view folder. So you should give apache to write permission to these folder. By default: SELinux say the /var/www folder should be read-only by the apache deamon.

So for this, we can set the selinux as 0: setenforce 0

This can solve problem temporally, but this makes the mysql not working. so this is not so good solution.

You can set a read-write context to the storage folder with: (remember to setenforce 1 to test it out)

chcon -Rt httpd_sys_content_rw_t storage/

Then your problem will be fixed.

  1. and don't forget this composer update php artisan cache:clear

    These commands will be useful after or before.

    I hope you save your time. Good luck. Hacken

Nested JSON: How to add (push) new items to an object?

push is an Array method, for json object you may need to define it

this should do it:

library[title] = {"foregrounds" : foregrounds,"backgrounds" : backgrounds};

How can I select an element in a component template?

Instead of injecting ElementRef and using querySelector or similar from there, a declarative way can be used instead to access elements in the view directly:

<input #myname>
@ViewChild('myname') input; 

element

ngAfterViewInit() {
  console.log(this.input.nativeElement.value);
}

StackBlitz example

  • @ViewChild() supports directive or component type as parameter, or the name (string) of a template variable.
  • @ViewChildren() also supports a list of names as comma separated list (currently no spaces allowed @ViewChildren('var1,var2,var3')).
  • @ContentChild() and @ContentChildren() do the same but in the light DOM (<ng-content> projected elements).

descendants

@ContentChildren() is the only one that allows to also query for descendants

@ContentChildren(SomeTypeOrVarName, {descendants: true}) someField; 

{descendants: true} should be the default but is not in 2.0.0 final and it's considered a bug
This was fixed in 2.0.1

read

If there are a component and directives the read parameter allows to specify which instance should be returned.

For example ViewContainerRef that is required by dynamically created components instead of the default ElementRef

@ViewChild('myname', { read: ViewContainerRef }) target;

subscribe changes

Even though view children are only set when ngAfterViewInit() is called and content children are only set when ngAfterContentInit() is called, if you want to subscribe to changes of the query result, it should be done in ngOnInit()

https://github.com/angular/angular/issues/9689#issuecomment-229247134

@ViewChildren(SomeType) viewChildren;
@ContentChildren(SomeType) contentChildren;

ngOnInit() {
  this.viewChildren.changes.subscribe(changes => console.log(changes));
  this.contentChildren.changes.subscribe(changes => console.log(changes));
}

direct DOM access

can only query DOM elements, but not components or directive instances:

export class MyComponent {
  constructor(private elRef:ElementRef) {}
  ngAfterViewInit() {
    var div = this.elRef.nativeElement.querySelector('div');
    console.log(div);
  }

  // for transcluded content
  ngAfterContentInit() {
    var div = this.elRef.nativeElement.querySelector('div');
    console.log(div);
  }
}

get arbitrary projected content

See Access transcluded content

How to test an SQL Update statement before running it?

Not a direct answer, but I've seen many borked prod data situations that could have been avoided by typing the WHERE clause first! Sometimes a WHERE 1 = 0 can help with putting a working statement together safely too. And looking at an estimated execution plan, which will estimate rows affected, can be useful. Beyond that, in a transaction that you roll back as others have said.

How to make grep only match if the entire line matches?

grep -Fx ABB.log a.tmp

From the grep man page:

-F, --fixed-strings
Interpret PATTERN as a (list of) fixed strings
-x, --line-regexp
Select only those matches that exactly match the whole line.

python time + timedelta equivalent

If it's worth adding another file / dependency to your project, I've just written a tiny little class that extends datetime.time with the ability to do arithmetic. If you go past midnight, it just wraps around:

>>> from nptime import nptime
>>> from datetime import timedelta
>>> afternoon = nptime(12, 24) + timedelta(days=1, minutes=36)
>>> afternoon
nptime(13, 0)
>>> str(afternoon)
'13:00:00'

It's available from PyPi as nptime ("non-pedantic time"), or on GitHub: https://github.com/tgs/nptime

The documentation is at http://tgs.github.io/nptime/

How to reverse a singly linked list using only two pointers?

curr = head;
prev = NULL;

while (curr != NULL) {
    next = curr->next; // store current's next, since it will be overwritten
    curr->next = prev;
    prev = curr;
    curr = next;
}

head = prev; // update head

git clone through ssh

Git 101:

git is a decentralized version control system. You do not necessary need a server to get up and running with git. Still you might want to do that as it looks cool, right? (It's also useful if you want to work on a single project from multiple computers.)

So to get a "server" running you need to run git init --bare <your_project>.git as this will create an empty repository, which you can then import on your machines without having to muck around in config files in your .git dir.

After this you could clone the repo on your clients as it is supposed to work, but I found that some clients (namely git-gui) will fail to clone a repo that is completely empty. To work around this you need to run cd <your_project>.git && touch <some_random_file> && git add <some_random_file> && git commit && git push origin master. (Note that you might need to configure your username and email for that machine's git if you hadn't done so in the past. The actual commands to run will be in the error message you get so I'll just omit them.)

So at this point you can clone the repository to any machine simply by running git clone <user>@<server>:<relative_path><your_project>.git. (As others have pointed out you might need to prefix it with ssh:// if you use the absolute path.) This assumes that you can already log in from your client to the server. (You'll also get bonus points for setting up a config file and keys for ssh, if you intend to push a lot of stuff to the remote server.)

Some relevant links:
This pretty much tells you what you need to know.
And this is for those who know the basic workings of git but sometimes forget the exact syntax.

Send cookies with curl

if you have Firebug installed on Firefox, just open the url. In the network panel, right-click and select Copy as cURL. You can see all curl parameters for this web call.

Calling a php function by onclick event

Use this html code it will surely help you

<input type="button" value="NEXT"  onclick="document.write('<?php //call a function here ex- 'fun();' ?>');" />

one limitation is that it is taking more time to run so wait for few seconds it will work

How can I rebuild indexes and update stats in MySQL innoDB?

To date (mysql 8.0.18) there is no suitable function inside mysql to re-create indexes.
Since mysql 8.0 myisam is slowly phasing into deprecated status, innodb is the current main storage engine.
In most practical cases innodb is the best choice and it's supposed to keep indexes working well.
In most practical cases innodb also does a good job, you do not need to recreate indexes. Almost always.

When it comes to large tables with hundreds of GB data amd rows and a lot of writing the situation changes, indexes can degrade in performance.
In my personal case I've seen performance drop from ~15 minutes for a count(*) using a secondary index to 4300 minutes after 2 months of writing to the table with linear time increase.
After recreating the index the performance goes back to 15 minutes.

To date we have two options to do that:
1) OPTIMIZE TABLE (or ALTER TABLE)
Innodb doesn't support optimization so in both cases the entire table will be read and re-created.
This means you need the storage for the temporary file and depending on the table a lot of time (I've cases where an optimize takes a week to complete). This will compact the data and rebuild all indexes.
Despite not being officially recommended, I highly recommend the OPTIMIZE process on write-heavy tables up to 100GB in size.

2) ALTER TABLE DROP KEY -> ALTER TABLE ADD KEY
You manually drop the key by name, you manually create it again. In a production environment you'll want to create it first, then drop the old version.
The upside: this can be a lot faster than optimize. The downside: you need to manually create the syntax.
"SHOW CREATE TABLE" can be used to quickly see which indexes are available and how they are called.

Appendix:
1) To just update statistics you can use the already mentioned "ANALYZE TABLE".
2) If you experience performance degradation on write-heavy servers you might need to restart mysql. There are a couple of bugs in current mysql (8.0) that can cause significant slowdown without showing up in error log. Eventually those slowdowns lead to a server crash but it can take weeks or even months to build up to the crash, in this process the server gets slower and slower in responses.
3) If you wish to re-create a large table that takes weeks to complete or fails after hours due to internal data integrity problems you should do a CREATE TABLE LIKE, INSERT INTO SELECT *. then 'atomic RENAME' the tables.
4) If INSERT INTO SELECT * takes hours to days to complete on huge tables you can speed up the process by about 20-30 times using a multi-threaded approach. You "partition" the table into chunks and INSERT INTO SELECT * in parallel.

How to push to History in React Router v4?

so the way I do it is: - instead of redirecting using history.push, I just use Redirect component from react-router-dom When using this component you can just pass push=true, and it will take care of the rest

import * as React from 'react';
import { Redirect } from 'react-router-dom';
class Example extends React.Component {
  componentDidMount() {
    this.setState({
      redirectTo: '/test/path'
    });
  }

  render() {
    const { redirectTo } = this.state;

    return <Redirect to={{pathname: redirectTo}} push={true}/>
  }
}

Java error: Comparison method violates its general contract

It might also be an OpenJDK bug... (not in this case but it is the same error)

If somebody like me stumbles upon this answer regarding the

java.lang.IllegalArgumentException: Comparison method violates its general contract!

then it might also be a bug in the Java-Version. I have a compareTo running since several years now in some applications. But suddenly it stopped working and throws the error after all compares were done (i compare 6 Attributes before returning "0").

Now I just found this Bugreport of OpenJDK:

How to create a listbox in HTML without allowing multiple selection?

For Asp.Net MVC

@Html.ListBox("parameterName", ViewBag.ParameterValueList as MultiSelectList, 
 new { 
 @class = "chosen-select form-control"
 }) 

or

  @Html.ListBoxFor(model => model.parameterName,
  ViewBag.ParameterValueList as MultiSelectList,
   new{
       data_placeholder = "Select Options ",
       @class = "chosen-select form-control"
   })

Logo image and H1 heading on the same line

you can do this by using just one line code..

<h1><img src="img/logo.png" alt="logo"/>My website name</h1>

Cast to generic type in C#

I struggled to solve a similar problem around data table classes instead of messages. The root issue mentioned above of casting a non-generic version of the class to a derived generic version was the same.

In order to allow injection into a portable class library which did not support database libraries, I introduced a set of interface classes, with the intent that I could pass a type and get a matching generic. It ended up needing to implement a generic method.

// Interface for injection
public interface IDatabase
{
    // Original, non-functional signature:
    IDatatable<object> GetDataTable(Type dataType);

    // Functional method using a generic method:
    IDatatable<T> GetDataTable<T>();
}

And this the whole implementation using the generic method above.

The generic class that will be cast from a dictionary.

// Non-generic base class allows listing tables together
abstract class Datatable
{
    Datatable(Type storedClass)
    {
      StoredClass = storedClass;
    }

    Type StoredClass { get; private set; }
}

// Generic inheriting class
abstract class Datatable<T>: Datatable, IDatatable<T>
{
    protected Datatable()
        :base(typeof(T))
    {
    }
}

This is the class that stores the generic class and casts it to satisfy the generic method in the interface

class Database
{
    // Dictionary storing the classes using the non-generic base class
    private Dictionary<Type, Datatable> _tableDictionary;

    protected Database(List<Datatable> tables)
    {
        _tableDictionary = new Dictionary<Type, Datatable>();
        foreach (var table in tables)
        {
            _tableDictionary.Add(table.StoredClass, table);
        }
    }

    // Interface implementation, casts the generic
    public IDatatable<T> GetDataTable<T>()
    {
        Datatable table = null;

        _tableDictionary.TryGetValue(typeof(T), out table);

        return table as IDatatable<T>;
    }
}

And finally the calling of the interface method.

IDatatable<CustomerAccount> table = _database.GetDataTable<CustomerAccount>();

Synchronous request in Node.js

This code can be used to execute an array of promises synchronously & sequentially after which you can execute your final code in the .then() call.

const allTasks = [() => promise1, () => promise2, () => promise3];

function executePromisesSync(tasks) {
  return tasks.reduce((task, nextTask) => task.then(nextTask), Promise.resolve());
}

executePromisesSync(allTasks).then(
  result => console.log(result),
  error => console.error(error)
);

Get current date/time in seconds

 Date.now()

gives milliseconds since epoch. No need to use new.

Check out the reference here: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/now

(Not supported in IE8.)

How to get only numeric column values?

SELECT column1 FROM table WHERE column1 not like '%[0-9]%'

Removing the '^' did it for me. I'm looking at a varchar field and when I included the ^ it excluded all of my non-numerics which is exactly what I didn't want. So, by removing ^ I only got non-numeric values back.

How to solve "java.io.IOException: error=12, Cannot allocate memory" calling Runtime#exec()?

I solved this using JNA: https://github.com/twall/jna

import com.sun.jna.Library;
import com.sun.jna.Native;
import com.sun.jna.Platform;

public class prova {

    private interface CLibrary extends Library {
        CLibrary INSTANCE = (CLibrary) Native.loadLibrary((Platform.isWindows() ? "msvcrt" : "c"), CLibrary.class);
        int system(String cmd);
    }

    private static int exec(String command) {
        return CLibrary.INSTANCE.system(command);
    }

    public static void main(String[] args) {
        exec("ls");
    }
}

Java File - Open A File And Write To It

To expand upon Mr. Eels comment, you can do it like this:

    File file = new File("C:\\A.txt");
    FileWriter writer;
    try {
        writer = new FileWriter(file, true);
        PrintWriter printer = new PrintWriter(writer);
        printer.append("Sue");
        printer.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Don't say we ain't good to ya!

jQuery ajax call to REST service

From the use of 8080 I'm assuming you are using a tomcat servlet container to serve your rest api. If this is the case you can also consider to have your webserver proxy the requests to the servlet container.

With apache you would typically use mod_jk (although there are other alternatives) to serve the api trough the web server behind port 80 instead of 8080 which would solve the cross domain issue.

This is common practice, have the 'static' content in the webserver and dynamic content in the container, but both served from behind the same domain.

The url for the rest api would be http://localhost/restws/json/product/get

Here a description on how to use mod_jk to connect apache to tomcat: http://tomcat.apache.org/connectors-doc/webserver_howto/apache.html

Video streaming over websockets using JavaScript

The Media Source Extensions has been proposed which would allow for Adaptive Bitrate Streaming implementations.

Read CSV file column by column

You should use the excellent OpenCSV for reading and writing CSV files. To adapt your example to use the library it would look like this:

public class ParseCSV {
  public static void main(String[] args) {
    try {
      //csv file containing data
      String strFile = "C:/Users/rsaluja/CMS_Evaluation/Drupal_12_08_27.csv";
      CSVReader reader = new CSVReader(new FileReader(strFile));
      String [] nextLine;
      int lineNumber = 0;
      while ((nextLine = reader.readNext()) != null) {
        lineNumber++;
        System.out.println("Line # " + lineNumber);

        // nextLine[] is an array of values from the line
        System.out.println(nextLine[4] + "etc...");
      }
    }
  }
}

Read a file in Node.js

var fs = require('fs');
var path = require('path');

exports.testDir = path.dirname(__filename);
exports.fixturesDir = path.join(exports.testDir, 'fixtures');
exports.libDir = path.join(exports.testDir, '../lib');
exports.tmpDir = path.join(exports.testDir, 'tmp');
exports.PORT = +process.env.NODE_COMMON_PORT || 12346;

// Read File
fs.readFile(exports.tmpDir+'/start.html', 'utf-8', function(err, content) {
  if (err) {
    got_error = true;
  } else {
    console.log('cat returned some content: ' + content);
    console.log('this shouldn\'t happen as the file doesn\'t exist...');
    //assert.equal(true, false);
  }
});

Linq where clause compare only date value without time value

There is also EntityFunctions.TruncateTime or DbFunctions.TruncateTime in EF 6.0

How to create/make rounded corner buttons in WPF?

This is more of a minimal control template to get a button with rounded corners, however you will not have any hover or click visual effects. But you can add these to the control template as needed. I was working with a dark background, hence the white background.

<Style x:Key="RoundedButtonStyle" TargetType="{x:Type Button}">
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="Button">
                <Border CornerRadius="15" Background="White" BorderThickness="1" Padding="2">
                    <ContentPresenter HorizontalAlignment="Center" VerticalAlignment="Center" />
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

I used the control template from the following blog post as my starting point: http://shihac-sharp.blogspot.com.au/2012/05/button-with-rounded-corners-in-wpf.html

css transition opacity fade background

Please note that the problem is not white color. It is because it is being transparent.

When an element is made transparent, all of its child element's opacity; alpha filter in IE 6 7 etc, is changed to the new value.

So you cannot say that it is white!

You can place an element above it, and change that element's transparency to 1 while changing the image's transparency to .2 or what so ever you want to.

Java Regex Capturing Groups

The issue you're having is with the type of quantifier. You're using a greedy quantifier in your first group (index 1 - index 0 represents the whole Pattern), which means it'll match as much as it can (and since it's any character, it'll match as many characters as there are in order to fulfill the condition for the next groups).

In short, your 1st group .* matches anything as long as the next group \\d+ can match something (in this case, the last digit).

As per the 3rd group, it will match anything after the last digit.

If you change it to a reluctant quantifier in your 1st group, you'll get the result I suppose you are expecting, that is, the 3000 part.

Note the question mark in the 1st group.

String line = "This order was placed for QT3000! OK?";
Pattern pattern = Pattern.compile("(.*?)(\\d+)(.*)");
Matcher matcher = pattern.matcher(line);
while (matcher.find()) {
    System.out.println("group 1: " + matcher.group(1));
    System.out.println("group 2: " + matcher.group(2));
    System.out.println("group 3: " + matcher.group(3));
}

Output:

group 1: This order was placed for QT
group 2: 3000
group 3: ! OK?

More info on Java Pattern here.

Finally, the capturing groups are delimited by round brackets, and provide a very useful way to use back-references (amongst other things), once your Pattern is matched to the input.

In Java 6 groups can only be referenced by their order (beware of nested groups and the subtlety of ordering).

In Java 7 it's much easier, as you can use named groups.

Check list of words in another string

Easiest and Simplest method of solving this problem is using re

import re

search_list = ['one', 'two', 'there']
long_string = 'some one long two phrase three'
if re.compile('|'.join(search_list),re.IGNORECASE).search(long_string): #re.IGNORECASE is used to ignore case
    # Do Something if word is present
else:
    # Do Something else if word is not present

Add alternating row color to SQL Server Reporting services report

My problem was that I wanted all the columns in a row to have the same background. I grouped both by row and by column, and with the top two solutions here I got all the rows in column 1 with a colored background, all the rows in column 2 with a white background, all the rows in column 3 with a colored background, and so on. It's as if RowNumber and bOddRow (of Catch22's solution) pay attention to my column group instead of ignoring that and only alternating with a new row.

What I wanted is for all the columns in row 1 to have a white background, then all the columns in row 2 to have a colored background, then all the columns in row 3 to have a white background, and so on. I got this effect by using the selected answer but instead of passing Nothing to RowNumber, I passed the name of my column group, e.g.

=IIf(RowNumber("MyColumnGroupName") Mod 2 = 0, "AliceBlue", "Transparent")

Thought this might be useful to someone else.

Postgresql: password authentication failed for user "postgres"

Here are some combinations which I tried to login:

# login via user foo
psql -Ufoo -h localhost

sudo -u postgres psql postgres

# user foo login to postgres db
psql -Ufoo -h localhost -d postgres

How to select Python version in PyCharm?

I think you are saying that you have python2 and python3 installed and have added a reference to each version under Pycharm > Settings > Project Interpreter

What I think you are asking is how do you have some projects run with Python 2 and some projects running with Python 3.

If so, you can look under Run > Edit Configurations

PyCharm Run > Edit Configurations

How to cd into a directory with space in the name?

Cygwin has issue recognizing space in between the PC name. So to solve this, you have to use "\" after the first word then include the space, then the last name.

such as ".../my\ dir/"

$ cd /cygdrive/c/Users/my\ dir/Documents

Another interesting and simple way to do it, is to put the directory in quotation marks ("")

e.g run it as follows:

$ cd c:
$ cd Users
$ cd "my dir"
$ cd Documents

Hope it works?

Nginx subdomain configuration

Another type of solution would be to autogenerate the nginx conf files via Jinja2 templates from ansible. The advantage of this is easy deployment to a cloud environment, and easy to replicate on multiple dev machines

How to add files/folders to .gitignore in IntelliJ IDEA?

Intellij had .ignore plugin to support this. https://plugins.jetbrains.com/plugin/7495?pr=idea

After you install the plugin, you right click on the project and select new -> .ignore file -> .gitignore file (Git) enter image description here

Then, select the type of project you have to generate a template and click Generate. enter image description here

How to minify php page html output?

I've tried several minifiers and they either remove too little or too much.

This code removes redundant empty spaces and optional HTML (ending) tags. Also it plays it safe and does not remove anything that could potentially break HTML, JS or CSS.

Also the code shows how to do that in Zend Framework:

class Application_Plugin_Minify extends Zend_Controller_Plugin_Abstract {

  public function dispatchLoopShutdown() {
    $response = $this->getResponse();
    $body = $response->getBody(); //actually returns both HEAD and BODY

    //remove redundant (white-space) characters
    $replace = array(
        //remove tabs before and after HTML tags
        '/\>[^\S ]+/s'   => '>',
        '/[^\S ]+\</s'   => '<',
        //shorten multiple whitespace sequences; keep new-line characters because they matter in JS!!!
        '/([\t ])+/s'  => ' ',
        //remove leading and trailing spaces
        '/^([\t ])+/m' => '',
        '/([\t ])+$/m' => '',
        // remove JS line comments (simple only); do NOT remove lines containing URL (e.g. 'src="http://server.com/"')!!!
        '~//[a-zA-Z0-9 ]+$~m' => '',
        //remove empty lines (sequence of line-end and white-space characters)
        '/[\r\n]+([\t ]?[\r\n]+)+/s'  => "\n",
        //remove empty lines (between HTML tags); cannot remove just any line-end characters because in inline JS they can matter!
        '/\>[\r\n\t ]+\</s'    => '><',
        //remove "empty" lines containing only JS's block end character; join with next line (e.g. "}\n}\n</script>" --> "}}</script>"
        '/}[\r\n\t ]+/s'  => '}',
        '/}[\r\n\t ]+,[\r\n\t ]+/s'  => '},',
        //remove new-line after JS's function or condition start; join with next line
        '/\)[\r\n\t ]?{[\r\n\t ]+/s'  => '){',
        '/,[\r\n\t ]?{[\r\n\t ]+/s'  => ',{',
        //remove new-line after JS's line end (only most obvious and safe cases)
        '/\),[\r\n\t ]+/s'  => '),',
        //remove quotes from HTML attributes that does not contain spaces; keep quotes around URLs!
        '~([\r\n\t ])?([a-zA-Z0-9]+)="([a-zA-Z0-9_/\\-]+)"([\r\n\t ])?~s' => '$1$2=$3$4', //$1 and $4 insert first white-space character found before/after attribute
    );
    $body = preg_replace(array_keys($replace), array_values($replace), $body);

    //remove optional ending tags (see http://www.w3.org/TR/html5/syntax.html#syntax-tag-omission )
    $remove = array(
        '</option>', '</li>', '</dt>', '</dd>', '</tr>', '</th>', '</td>'
    );
    $body = str_ireplace($remove, '', $body);

    $response->setBody($body);
  }
}

But note that when using gZip compression your code gets compressed a lot more that any minification can do so combining minification and gZip is pointless, because time saved by downloading is lost by minification and also saves minimum.

Here are my results (download via 3G network):

 Original HTML:        150kB       180ms download
 gZipped HTML:          24kB        40ms
 minified HTML:        120kB       150ms download + 150ms minification
 min+gzip HTML:         22kB        30ms download + 150ms minification

SQLite string contains other string query

Using LIKE:

SELECT *
  FROM TABLE
 WHERE column LIKE '%cats%'  --case-insensitive

How to use SortedMap interface in Java?

You can use TreeMap which internally implements the SortedMap below is the example

Sorting by ascending ordering :

  Map<Float, String> ascsortedMAP = new TreeMap<Float, String>();

  ascsortedMAP.put(8f, "name8");
  ascsortedMAP.put(5f, "name5");
  ascsortedMAP.put(15f, "name15");
  ascsortedMAP.put(35f, "name35");
  ascsortedMAP.put(44f, "name44");
  ascsortedMAP.put(7f, "name7");
  ascsortedMAP.put(6f, "name6");

  for (Entry<Float, String> mapData : ascsortedMAP.entrySet()) {
    System.out.println("Key : " + mapData.getKey() + "Value : " + mapData.getValue());
  }

Sorting by descending ordering :

If you always want this create the map to use descending order in general, if you only need it once create a TreeMap with descending order and put all the data from the original map in.

  // Create the map and provide the comparator as a argument
  Map<Float, String> dscsortedMAP = new TreeMap<Float, String>(new Comparator<Float>() {
    @Override
    public int compare(Float o1, Float o2) {
      return o2.compareTo(o1);
    }
  });
  dscsortedMAP.putAll(ascsortedMAP);

for further information about SortedMAP read http://examples.javacodegeeks.com/core-java/util/treemap/java-sorted-map-example/

New warnings in iOS 9: "all bitcode will be dropped"

To fix the issues with the canOpenURL failing. This is because of the new App Transport Security feature in iOS9

Read this post to fix that issue http://discoverpioneer.com/blog/2015/09/18/updating-facebook-integration-for-ios-9/

What is the height of iPhone's onscreen keyboard?

version note: this is no longer value in iOS 9 & 10, as they support custom keyboard sizes.

This depends on the model and the QuickType bar:

enter image description here

http://www.idev101.com/code/User_Interface/sizes.html

Run command on the Ansible host

Yes, you can run commands on the Ansible host. You can specify that all tasks in a play run on the Ansible host, or you can mark individual tasks to run on the Ansible host.

If you want to run an entire play on the Ansible host, then specify hosts: 127.0.0.1 and connection:local in the play, for example:

- name: a play that runs entirely on the ansible host
  hosts: 127.0.0.1
  connection: local
  tasks:
  - name: check out a git repository
    git: repo=git://foosball.example.org/path/to/repo.git dest=/local/path

See Local Playbooks in the Ansible documentation for more details.

If you just want to run a single task on your Ansible host, you can use local_action to specify that a task should be run locally. For example:

- name: an example playbook
  hosts: webservers
  tasks:
  - ...

  - name: check out a git repository
    local_action: git repo=git://foosball.example.org/path/to/repo.git dest=/local/path

See Delegation in the Ansible documentation for more details.

Edit: You can avoid having to type connection: local in your play by adding this to your inventory:

localhost ansible_connection=local

(Here you'd use "localhost" instead of "127.0.0.1" to refer to the play).

Edit: In newer versions of ansible, you no longer need to add the above line to your inventory, ansible assumes it's already there.

Merge two Excel tables Based on matching data in Columns

Put the table in the second image on Sheet2, columns D to F.

In Sheet1, cell D2 use the formula

=iferror(vlookup($A2,Sheet2!$D$1:$F$100,column(A1),false),"")

copy across and down.

Edit: here is a picture. The data is in two sheets. On Sheet1, enter the formula into cell D2. Then copy the formula across to F2 and then down as many rows as you need.

enter image description here

Format cell if cell contains date less than today

Your first problem was you weren't using your compare symbols correctly.

< less than
> greater than
<= less than or equal to
>= greater than or equal to

To answer your other questions; get the condition to work on every cell in the column and what about blanks?

What about blanks?

Add an extra IF condition to check if the cell is blank or not, if it isn't blank perform the check. =IF(B2="","",B2<=TODAY())

Condition on every cell in column

enter image description here

can we use xpath with BeautifulSoup?

I can confirm that there is no XPath support within Beautiful Soup.

How to change context root of a dynamic web project in Eclipse?

I tried out solution suggested by Russ Bateman Here in the post

http://localhost:8080/Myapp to http://localhost:8080/somepath/Myapp

But Didnt worked for me as I needed to have a *.war file that can hold the config and not the individual instance of server on my localmachine.

Reference

In order to do that I need jboss-web.xml placed in WEB-INF

<?xml version="1.0" encoding="UTF-8"?>
 <!--
Copyright (c) 2008 Object Computing, Inc.
All rights reserved.
-->
<!DOCTYPE jboss-web PUBLIC "-//JBoss//DTD Web Application 4.2//EN"
"http://www.jboss.org/j2ee/dtd/jboss-web_4_2.dtd">

  <jboss-web>
  <context-root>somepath/Myapp</context-root>
  </jboss-web>

Is optimisation level -O3 dangerous in g++?

In the early days of gcc (2.8 etc.) and in the times of egcs, and redhat 2.96 -O3 was quite buggy sometimes. But this is over a decade ago, and -O3 is not much different than other levels of optimizations (in buggyness).

It does however tend to reveal cases where people rely on undefined behavior, due to relying more strictly on the rules, and especially corner cases, of the language(s).

As a personal note, I am running production software in the financial sector for many years now with -O3 and have not yet encountered a bug that would not have been there if I would have used -O2.

By popular demand, here an addition:

-O3 and especially additional flags like -funroll-loops (not enabled by -O3) can sometimes lead to more machine code being generated. Under certain circumstances (e.g. on a cpu with exceptionally small L1 instruction cache) this can cause a slowdown due to all the code of e.g. some inner loop now not fitting anymore into L1I. Generally gcc tries quite hard to not to generate so much code, but since it usually optimizes the generic case, this can happen. Options especially prone to this (like loop unrolling) are normally not included in -O3 and are marked accordingly in the manpage. As such it is generally a good idea to use -O3 for generating fast code, and only fall back to -O2 or -Os (which tries to optimize for code size) when appropriate (e.g. when a profiler indicates L1I misses).

If you want to take optimization into the extreme, you can tweak in gcc via --param the costs associated with certain optimizations. Additionally note that gcc now has the ability to put attributes at functions that control optimization settings just for these functions, so when you find you have a problem with -O3 in one function (or want to try out special flags for just that function), you don't need to compile the whole file or even whole project with O2.

otoh it seems that care must be taken when using -Ofast, which states:

-Ofast enables all -O3 optimizations. It also enables optimizations that are not valid for all standard compliant programs.

which makes me conclude that -O3 is intended to be fully standards compliant.

Is null reference possible?

References are not pointers.

8.3.2/1:

A reference shall be initialized to refer to a valid object or function. [Note: in particular, a null reference cannot exist in a well-defined program, because the only way to create such a reference would be to bind it to the “object” obtained by dereferencing a null pointer, which causes undefined behavior. As described in 9.6, a reference cannot be bound directly to a bit-field. ]

1.9/4:

Certain other operations are described in this International Standard as undefined (for example, the effect of dereferencing the null pointer)

As Johannes says in a deleted answer, there's some doubt whether "dereferencing a null pointer" should be categorically stated to be undefined behavior. But this isn't one of the cases that raise doubts, since a null pointer certainly does not point to a "valid object or function", and there is no desire within the standards committee to introduce null references.

Delete all rows with timestamp older than x days

DELETE FROM on_search 
WHERE search_date < UNIX_TIMESTAMP(DATE_SUB(NOW(), INTERVAL 180 DAY))

Getting started with Haskell

Some colleague of mine had good experience with Learn You a Haskell for Great Good!.

Tutorial aimed at people who have experience in imperative programming languages but haven't programmed in a functional language before.

And check the answers here too

How to wait until an element exists?

I have developed an answer inspired by Jamie Hutber's.

It's a promise based function where you can set:

  • maximum number of tries - default 10;
  • delay in milliseconds - default 100 ms.

Therefore, by default, it will wait 1 second until the element appears on the DOM.

If it does not show up it will return a promise.reject with null so you can handle the error as per your wish.

Code


function waitForElement(selector, delay = 1000, tries = 10) {
  const element = document.querySelector(selector);

  // creates a local variable w/ the name of the selector to keep track of all tries
  if (!window[`__${selector}`]) {
    window[`__${selector}`] = 0;
  }

  function _search() {
    return new Promise((resolve) => {
      window[`__${selector}`]++;
      console.log(window[`__${selector}`]);
      setTimeout(resolve, delay);
    });
  }

  //element not found, retry
  if (element === null) {
    if (window[`__${selector}`] >= tries) {
      window[`__${selector}`] = 0;
      return Promise.reject(null);
    }

    return _search().then(() => waitForElement(selector));
  } else {
    return Promise.resolve(element);
  }
}

Usage:

async function wait(){
    try{
        const $el = await waitForElement(".llama");
        console.log($el);
    } catch(err){
        console.error("Timeout - couldn't find element.")
    }
} 

wait();

In the example above it will wait for the selector .llama. You can add a greater delay and test it here on the console of StackoverFlow.

Just add the class llama to any element on the DOM.

How do you scroll up/down on the console of a Linux VM

Fn + Up/Down can scroll Terminal in Mac OS X 10.11

How to increase maximum execution time in php

use below statement if safe_mode is off

set_time_limit(0);

What is the difference between find(), findOrFail(), first(), firstOrFail(), get(), list(), toArray()

  1. find($id) takes an id and returns a single model. If no matching model exist, it returns null.

  2. findOrFail($id) takes an id and returns a single model. If no matching model exist, it throws an error1.

  3. first() returns the first record found in the database. If no matching model exist, it returns null.

  4. firstOrFail() returns the first record found in the database. If no matching model exist, it throws an error1.

  5. get() returns a collection of models matching the query.

  6. pluck($column) returns a collection of just the values in the given column. In previous versions of Laravel this method was called lists.

  7. toArray() converts the model/collection into a simple PHP array.


Note: a collection is a beefed up array. It functions similarly to an array, but has a lot of added functionality, as you can see in the docs.

Unfortunately, PHP doesn't let you use a collection object everywhere you can use an array. For example, using a collection in a foreach loop is ok, put passing it to array_map is not. Similarly, if you type-hint an argument as array, PHP won't let you pass it a collection. Starting in PHP 7.1, there is the iterable typehint, which can be used to accept both arrays and collections.

If you ever want to get a plain array from a collection, call its all() method.


1 The error thrown by the findOrFail and firstOrFail methods is a ModelNotFoundException. If you don't catch this exception yourself, Laravel will respond with a 404, which is what you want most of the time.

How do I make Git use the editor of my choice for commits?

For Windows users who want to use neovim with the Windows Subsystem for Linux:

git config core.editor "C:/Windows/system32/bash.exe --login -c 'nvim .git/COMMIT_EDITMSG'"

This is not a fool-proof solution as it doesn't handle interactive rebasing (for example). Improvements very welcome!

Convert Bitmap to File

Most of the answers are too lengthy or too short not fulfilling the purpose. For those how are looking for Java or Kotlin code to Convert bitmap to File Object. Here is the detailed article I have written on the topic. Convert Bitmap to File in Android

public static File bitmapToFile(Context context,Bitmap bitmap, String fileNameToSave) { // File name like "image.png"
        //create a file to write bitmap data
        File file = null;
        try {
            file = new File(Environment.getExternalStorageDirectory() + File.separator + fileNameToSave);
            file.createNewFile();

//Convert bitmap to byte array
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            bitmap.compress(Bitmap.CompressFormat.PNG, 0 , bos); // YOU can also save it in JPEG
            byte[] bitmapdata = bos.toByteArray();

//write the bytes in file
            FileOutputStream fos = new FileOutputStream(file);
            fos.write(bitmapdata);
            fos.flush();
            fos.close();
            return file;
        }catch (Exception e){
            e.printStackTrace();
            return file; // it will return null
        }
    }

Generate UML Class Diagram from Java Project

I´d say MoDisco is by far the most powerful one (though probably not the easiest one to work with).

MoDisco is a generic reverse engineering framework (so that you can customize your reverse engineering project, with MoDisco you can even reverse engineer the behaviour of the java methods, not only the structure and signatures) but also includes some predefined features like the generation of class diagrams out of Java code that you need.