Programs & Examples On #Scope identity

Inserting into Oracle and retrieving the generated sequence ID

Expanding a bit on the answers from @Guru and @Ronnis, you can hide the sequence and make it look more like an auto-increment using a trigger, and have a procedure that does the insert for you and returns the generated ID as an out parameter.

create table batch(batchid number,
    batchname varchar2(30),
    batchtype char(1),
    source char(1),
    intarea number)
/

create sequence batch_seq start with 1
/

create trigger batch_bi
before insert on batch
for each row
begin
    select batch_seq.nextval into :new.batchid from dual;
end;
/

create procedure insert_batch(v_batchname batch.batchname%TYPE,
    v_batchtype batch.batchtype%TYPE,
    v_source batch.source%TYPE,
    v_intarea batch.intarea%TYPE,
    v_batchid out batch.batchid%TYPE)
as
begin
    insert into batch(batchname, batchtype, source, intarea)
    values(v_batchname, v_batchtype, v_source, v_intarea)
    returning batchid into v_batchid;
end;
/

You can then call the procedure instead of doing a plain insert, e.g. from an anoymous block:

declare
    l_batchid batch.batchid%TYPE;
begin
    insert_batch(v_batchname => 'Batch 1',
        v_batchtype => 'A',
        v_source => 'Z',
        v_intarea => 1,
        v_batchid => l_batchid);
    dbms_output.put_line('Generated id: ' || l_batchid);

    insert_batch(v_batchname => 'Batch 99',
        v_batchtype => 'B',
        v_source => 'Y',
        v_intarea => 9,
        v_batchid => l_batchid);
    dbms_output.put_line('Generated id: ' || l_batchid);
end;
/

Generated id: 1
Generated id: 2

You can make the call without an explicit anonymous block, e.g. from SQL*Plus:

variable l_batchid number;
exec insert_batch('Batch 21', 'C', 'X', 7, :l_batchid);

... and use the bind variable :l_batchid to refer to the generated value afterwards:

print l_batchid;
insert into some_table values(:l_batch_id, ...);

Left Join without duplicate rows from left table

Using the DISTINCT flag will remove duplicate rows.

SELECT DISTINCT
C.Content_ID,
C.Content_Title,
M.Media_Id

FROM tbl_Contents C
LEFT JOIN tbl_Media M ON M.Content_Id = C.Content_Id 
ORDER BY C.Content_DatePublished ASC

VBA to copy a file from one directory to another

Use the appropriate methods in Scripting.FileSystemObject. Then your code will be more portable to VBScript and VB.net. To get you started, you'll need to include:

Dim fso As Object
Set fso = VBA.CreateObject("Scripting.FileSystemObject")

Then you could use

Call fso.CopyFile(source, destination[, overwrite] )

where source and destination are the full names (including paths) of the file.

See https://docs.microsoft.com/en-us/office/vba/Language/Reference/user-interface-help/copyfile-method

Newline in string attribute

When you need to do it in a string (eg: in your resources) you need to use xml:space="preserve" and the ampersand character codes:

<System:String x:Key="TwoLiner" xml:space="preserve">First line&#10;Second line</System:String>

Or literal newlines in the text:

<System:String x:Key="TwoLiner" xml:space="preserve">First line 
Second line</System:String>

Warning: if you write code like the second example, you have inserted either a newline, or a carriage return and newline, depending on the line endings your operating system and/or text editor use. For instance, if you write that and commit it to git from a linux systems, everything may seem fine -- but if someone clones it to Windows, git will convert your line endings to \r\n and depending on what your string is for ... you might break the world.

Just be aware of that when you're preserving whitespace. If you write something like this:

<System:String x:Key="TwoLiner" xml:space="preserve">
First line 
Second line 
</System:String>

You've actually added four line breaks, possibly four carriage-returns, and potentially trailing white space that's invisible...

How to display list of repositories from subversion server

At my company they didn't configure the server to provide a list of repositories, so svn list worked for a specific repository but not at a higher level to list all repositories.

However they installed FishEye which gives you a GUI listing the repositories https://www.atlassian.com/software/fisheye

It's a paid option, so it's not for everyone, but the functionality is nice.

Ruby combining an array into one string

While a bit more cryptic than join, you can also multiply the array by a string.

@arr * " "

How to utilize date add function in Google spreadsheet?

In a fresh spreadsheet (US locale) with 12/19/11 in A1 and DT 30 in B1 then:

=A1+right(B1,2)

in say C1 returns 1/18/12.

As a string function RIGHT returns Text but that can be coerced into a number when adding. In adding a number to dates unity is treated as one day. Within (very wide) limits, months and even years are adjusted automatically.

How to move div vertically down using CSS

if div.title is a div then put this:

left: 0;
bottom: 0;

How do I get the classes of all columns in a data frame?

Hello was looking for the same, and it could be also

unlist(lapply(mtcars,class))

DeprecationWarning: Buffer() is deprecated due to security and usability issues when I move my script to another server

new Buffer(number)            // Old
Buffer.alloc(number)          // New

new Buffer(string)            // Old
Buffer.from(string)           // New

new Buffer(string, encoding)  // Old
Buffer.from(string, encoding) // New

new Buffer(...arguments)      // Old
Buffer.from(...arguments)     // New

Note that Buffer.alloc() is also faster on the current Node.js versions than new Buffer(size).fill(0), which is what you would otherwise need to ensure zero-filling.

Swift: Reload a View Controller

Whatever code you are writing in viewDidLoad, Add that in viewWillappear(). This will solve your problem.

How to connect to a remote MySQL database with Java?

Just supply the IP / hostname of the remote machine in your database connection string, instead of localhost. For example:

jdbc:mysql://192.168.15.25:3306/yourdatabase

Make sure there is no firewall blocking the access to port 3306

Also, make sure the user you are connecting with is allowed to connect from this particular hostname. For development environments it is safe to do this by 'username'@'%'. Check the user creation manual and the GRANT manual.

Equivalent to AssemblyInfo in dotnet core/csproj

Adding to NightOwl888's answer, you can go one step further and add an AssemblyInfo class rather than just a plain class:

enter image description here

How do I assert equality on two classes without an equals method?

Mockito offers a reflection-matcher:

For latest version of Mockito use:

Assert.assertTrue(new ReflectionEquals(expected, excludeFields).matches(actual));

For older versions use:

Assert.assertThat(actual, new ReflectionEquals(expected, excludeFields));

Does :before not work on img elements?

I found a way to make this work in pure css:

The I'm just fake content-method

a pure CSS method to enable img:after.

You can check out the CodePen: I'm just fake content or see the source.

Source & Snippet

_x000D_
_x000D_
img {_x000D_
    /* hide the default image */_x000D_
    height:0;_x000D_
    width:0;_x000D_
_x000D_
    /* hide fake content */_x000D_
    font-size:0;_x000D_
    color:transparent;_x000D_
_x000D_
    /* enable absolute position for pseudo elements */_x000D_
    position:relative;_x000D_
_x000D_
    /* and this is just fake content */_x000D_
    content:"I'm just fake content";_x000D_
}_x000D_
_x000D_
/* initial absolute position */_x000D_
img:before,_x000D_
img:after {_x000D_
    position:absolute;_x000D_
    top:0;_x000D_
    left:0;    _x000D_
}_x000D_
_x000D_
/* img:before - chrome & others */_x000D_
img:before {_x000D_
    content:url(http://placekitten.com/g/250/250);_x000D_
}_x000D_
_x000D_
/* img:before - firefox */_x000D_
body:not(:-moz-handler-blocked) img:before {_x000D_
    padding:125px;_x000D_
    background:url(http://placekitten.com/g/250/250) no-repeat;_x000D_
}_x000D_
_x000D_
/* img:after */_x000D_
img:after {_x000D_
    /* width of img:before */_x000D_
    left:250px;_x000D_
_x000D_
    content:url(http://lorempixel.com/350/200/city/1);_x000D_
}
_x000D_
<img_x000D_
    alt="You are watching the ~ I'm just fake content ~ method"  _x000D_
/>
_x000D_
_x000D_
_x000D_

Browser support

✓ Chrome 10+

✓ Firefox 11+

✓ Opera 9.8+

✓ Safari

No support

⊗ Internet Explorer 8 / 9

Please test in other browsers

Confused about UPDLOCK, HOLDLOCK

Why would UPDLOCK block selects? The Lock Compatibility Matrix clearly shows N for the S/U and U/S contention, as in No Conflict.

As for the HOLDLOCK hint the documentation states:

HOLDLOCK: Is equivalent to SERIALIZABLE. For more information, see SERIALIZABLE later in this topic.

...

SERIALIZABLE: ... The scan is performed with the same semantics as a transaction running at the SERIALIZABLE isolation level...

and the Transaction Isolation Level topic explains what SERIALIZABLE means:

No other transactions can modify data that has been read by the current transaction until the current transaction completes.

Other transactions cannot insert new rows with key values that would fall in the range of keys read by any statements in the current transaction until the current transaction completes.

Therefore the behavior you see is perfectly explained by the product documentation:

  • UPDLOCK does not block concurrent SELECT nor INSERT, but blocks any UPDATE or DELETE of the rows selected by T1
  • HOLDLOCK means SERALIZABLE and therefore allows SELECTS, but blocks UPDATE and DELETES of the rows selected by T1, as well as any INSERT in the range selected by T1 (which is the entire table, therefore any insert).
  • (UPDLOCK, HOLDLOCK): your experiment does not show what would block in addition to the case above, namely another transaction with UPDLOCK in T2:
    SELECT * FROM dbo.Test WITH (UPDLOCK) WHERE ...
  • TABLOCKX no need for explanations

The real question is what are you trying to achieve? Playing with lock hints w/o an absolute complete 110% understanding of the locking semantics is begging for trouble...

After OP edit:

I would like to select rows from a table and prevent the data in that table from being modified while I am processing it.

The you should use one of the higher transaction isolation levels. REPEATABLE READ will prevent the data you read from being modified. SERIALIZABLE will prevent the data you read from being modified and new data from being inserted. Using transaction isolation levels is the right approach, as opposed to using query hints. Kendra Little has a nice poster exlaining the isolation levels.

What is the difference between window, screen, and document in Javascript?

Well, the window is the first thing that gets loaded into the browser. This window object has the majority of the properties like length, innerWidth, innerHeight, name, if it has been closed, its parents, and more.

What about the document object then? The document object is your html, aspx, php, or other document that will be loaded into the browser. The document actually gets loaded inside the window object and has properties available to it like title, URL, cookie, etc. What does this really mean? That means if you want to access a property for the window it is window.property, if it is document it is window.document.property which is also available in short as document.property.

dom

That seems simple enough. But what happens once an IFRAME is introduced?

iframe

Rails: How can I rename a database column in a Ruby on Rails migration?

Run the below command to create a migration file:

rails g migration ChangeHasedPasswordToHashedPassword

Then in the file generated in the db/migrate folder, write rename_column as below:

class ChangeOldCoulmnToNewColumn < ActiveRecord::Migration
  def change
     rename_column :table_name, :hased_password, :hashed_password
  end
end

What is the point of "Initial Catalog" in a SQL Server connection string?

If the user name that is in the connection string has access to more then one database you have to specify the database you want the connection string to connect to. If your user has only one database available then you are correct that it doesn't matter. But it is good practice to put this in your connection string.

Composer could not find a composer.json

To install composer and add to your global path:

curl -sS https://getcomposer.org/installer | php
mv composer.phar /usr/local/bin/composer

run these in terminal. It does say if you get an error that usr doesn't exist, you do need to manually make it. I know an answer was selected, so this is for anyone who may see this in the future, as i am sometimes, and don't want to be advised to visit yet another site. Its simple just two lines, might have to be in sudo if you have permission error

Format telephone and credit card numbers in AngularJS

Here is the way I created ssn directive which checks for the the pattern and I have used RobinHerbots jquery.inputmask

angular.module('SocialSecurityNumberDirective', [])
       .directive('socialSecurityNumber', socialSecurityNumber);

function socialSecurityNumber() {
    var jquery = require('jquery');
    var inputmask = require("jquery.inputmask");
    return {
        require: 'ngModel',
        restrict: 'A',
        priority: 1000,
        link: function(scope,element, attr, ctrl) {

            var jquery_element = jquery(element);
            jquery_element.inputmask({mask:"***-**-****",autoUnmask:true});
            jquery_element.on('keyup paste focus blur', function() {
                var val = element.val();    
                ctrl.$setViewValue(val);
                ctrl.$render();

             });

            var pattern = /^\d{9}$/;

            var newValue = null;

            ctrl.$validators.ssnDigits = function(value) {
                 newValue = element.val();
                return newValue === '' ? true : pattern.test(newValue);    
            };
        }
    };
}

sudo: docker-compose: command not found

The output of dpkg -s ... demonstrates that docker-compose is not installed from a package. Without more information from you there are at least two possibilities:

  1. docker-compose simply isn't installed at all, and you need to install it.

    The solution here is simple: install docker-compose.

  2. docker-compose is installed in your $HOME directory (or other location not on root's $PATH).

    There are several solution in this case. The easiest is probably to replace:

    sudo docker-compose ...
    

    With:

    sudo `which docker-compose` ...
    

    This will call sudo with the full path to docker-compose.

    You could alternatively install docker-compose into a system-wide directory, such as /usr/local/bin.

wamp server does not start: Windows 7, 64Bit

For me it got resolved using following link: http://viralpatel.net/blogs/wamp-server-not-getting-started-problem/

where i was using skype and Wamp both installed and running

Entity Framework Queryable async

Long story short,
IQueryable is designed to postpone RUN process and firstly build the expression in conjunction with other IQueryable expressions, and then interprets and runs the expression as a whole.
But ToList() method (or a few sort of methods like that), are ment to run the expression instantly "as is".
Your first method (GetAllUrlsAsync), will run imediately, because it is IQueryable followed by ToListAsync() method. hence it runs instantly (asynchronous), and returns a bunch of IEnumerables.
Meanwhile your second method (GetAllUrls), won't get run. Instead, it returns an expression and CALLER of this method is responsible to run the expression.

Removing ul indentation with CSS

Remove this from #info:

    margin-left:auto;

Add this for your header:

#info p {
    text-align: center;
}

Do you need the fixed width etc.? I removed the in my opinion not necessary stuff and centered the header with text-align.

Sample
http://jsfiddle.net/Vc8CB/

How do I validate a date in rails?

Active Record gives you _before_type_cast attributes which contain the raw attribute data before typecasting. This can be useful for returning error messages with pre-typecast values or just doing validations that aren't possible after typecast.

I would shy away from Daniel Von Fange's suggestion of overriding the accessor, because doing validation in an accessor changes the accessor contract slightly. Active Record has a feature explicitly for this situation. Use it.

HTML form input tag name element array with JavaScript

To answer your questions in order:
1) There is no specific name for this. It's simply multiple elements with the same name (and in this case type as well). Name isn't unique, which is why id was invented (it's supposed to be unique).
2)

function getElementsByTagAndName(tag, name) {
    //you could pass in the starting element which would make this faster
    var elem = document.getElementsByTagName(tag);  
    var arr = new Array();
    var i = 0;
    var iarr = 0;
    var att;
    for(; i < elem.length; i++) {
        att = elem[i].getAttribute("name");
        if(att == name) {
            arr[iarr] = elem[i];
            iarr++;
        }
    }
    return arr;
}

Generate preview image from Video file?

I recommend php-ffmpeg library.

Extracting image

You can extract a frame at any timecode using the FFMpeg\Media\Video::frame method.

This code returns a FFMpeg\Media\Frame instance corresponding to the second 42. You can pass any FFMpeg\Coordinate\TimeCode as argument, see dedicated documentation below for more information.

$frame = $video->frame(FFMpeg\Coordinate\TimeCode::fromSeconds(42));
$frame->save('image.jpg');

If you want to extract multiple images from the video, you can use the following filter:

$video
    ->filters()
    ->extractMultipleFrames(FFMpeg\Filters\Video\ExtractMultipleFramesFilter::FRAMERATE_EVERY_10SEC, '/path/to/destination/folder/')
    ->synchronize();

$video
    ->save(new FFMpeg\Format\Video\X264(), '/path/to/new/file');

By default, this will save the frames as jpg images.

You are able to override this using setFrameFileType to save the frames in another format:

$frameFileType = 'jpg'; // either 'jpg', 'jpeg' or 'png'
$filter = new ExtractMultipleFramesFilter($frameRate, $destinationFolder);
$filter->setFrameFileType($frameFileType);

$video->addFilter($filter);

How do I fix the indentation of an entire file in Vi?

Before pasting into the terminal, try :set paste and then :set nopaste after you're done. This will turn off the auto-indent, line-wrap and other features that are messing up your paste.

edit: Also, I should point out that a much better result than = indenting can usually be obtained by using an external program. For example, I run :%!perltidy all the time. astyle, cindent, etc. can also be used. And, of course, you can map those to a key stroke, and map different ones to the same keystroke depending on file type.

Response.Redirect with POST instead of Get?

In PHP, you can send POST data with cURL. Is there something comparable for .NET?

Yes, HttpWebRequest, see my post below.

Add an image in a WPF button

I found that I also had to set the Access Modifier in the Resources tab to 'Public' - by default it was set to Internal and my icon only appeared in design mode but not when I ran the application.

Example of waitpid() in use?

The syntax is

pid_t waitpid(pid_t pid, int *statusPtr, int options);

1.where pid is the process of the child it should wait.

2.statusPtr is a pointer to the location where status information for the terminating process is to be stored.

3.specifies optional actions for the waitpid function. Either of the following option flags may be specified, or they can be combined with a bitwise inclusive OR operator:

WNOHANG WUNTRACED WCONTINUED

If successful, waitpid returns the process ID of the terminated process whose status was reported. If unsuccessful, a -1 is returned.

benifits over wait

1.Waitpid can used when you have more than one child for the process and you want to wait for particular child to get its execution done before parent resumes

2.waitpid supports job control

3.it supports non blocking of the parent process

Angularjs $http.get().then and binding to a list

Promise returned from $http can not be binded directly (I dont exactly know why). I'm using wrapping service that works perfectly for me:

.factory('DocumentsList', function($http, $q){
    var d = $q.defer();
    $http.get('/DocumentsList').success(function(data){
        d.resolve(data);
    });
    return d.promise;
});

and bind to it in controller:

function Ctrl($scope, DocumentsList) {
    $scope.Documents = DocumentsList;
    ...
}

UPDATE!:

In Angular 1.2 auto-unwrap promises was removed. See http://docs.angularjs.org/guide/migration#templates-no-longer-automatically-unwrap-promises

Updating a dataframe column in spark

DataFrames are based on RDDs. RDDs are immutable structures and do not allow updating elements on-site. To change values, you will need to create a new DataFrame by transforming the original one either using the SQL-like DSL or RDD operations like map.

A highly recommended slide deck: Introducing DataFrames in Spark for Large Scale Data Science.

Angular 2 Date Input not binding to date value

In .ts :

today: Date;

constructor() {  

    this.today =new Date();
}

.html:

<input type="date"  
       [ngModel]="today | date:'yyyy-MM-dd'"  
       (ngModelChange)="today = $event"    
       name="dt" 
       class="form-control form-control-rounded" #searchDate 
>

Git vs Team Foundation Server

On top of everything that's been said (

https://stackoverflow.com/a/4416666/172109

https://stackoverflow.com/a/4894099/172109

https://stackoverflow.com/a/4415234/172109

), which is correct, TFS isn't just a VCS. One major feature that TFS provides is natively integrated bug tracking functionality. Changesets are linked to issues and could be tracked. Various policies for check-ins are supported, as well as integration with Windows domain, which is what people who run TFS have. Tightly integrated GUI with Visual Studio is another selling point, which appeals to less than average mouse and click developer and his manager.

Hence comparing Git to TFS isn't a proper question to ask. Correct, though impractical, question is to compare Git with just VCS functionality of TFS. At that, Git blows TFS out of the water. However, any serious team needs other tools and this is where TFS provides one stop destination.

MVC ajax post to controller action method

$('#loginBtn').click(function(e) {
    e.preventDefault(); /// it should not have this code or else it wont continue
    //....
});

How to use requirements.txt to install all dependencies in a python project

(Taken from my comment)

pip won't handle system level dependencies. You'll have to apt-get install libfreetype6-dev before continuing. (It even says so right in your output. Try skimming over it for such errors next time, usually build outputs are very detailed)

Twitter - share button, but with image

Look into twitter cards.

The trick is not in the button but rather the page you are sharing. Twitter Cards pull the image from the meta tags similar to facebook sharing.

Example:

<meta name="twitter:card" content="summary_large_image">
<meta name="twitter:site" content="@site_username">
<meta name="twitter:title" content="Top 10 Things Ever">
<meta name="twitter:description" content="Up than 200 characters.">
<meta name="twitter:creator" content="@creator_username">
<meta name="twitter:image" content="http://placekitten.com/250/250">
<meta name="twitter:domain" content="YourDomain.com">

Python readlines() usage and efficient practice for reading

Read line by line, not the whole file:

for line in open(file_name, 'rb'):
    # process line here

Even better use with for automatically closing the file:

with open(file_name, 'rb') as f:
    for line in f:
        # process line here

The above will read the file object using an iterator, one line at a time.

C# guid and SQL uniqueidentifier

Store it in the database in a field with a data type of uniqueidentifier.

Is it possible to hide/encode/encrypt php source code and let others have the system?

https://toolki.com/en/php-decoder/

Decode hidden PHP eval(), gzinflate(), str_rot13(), str_replace() and base64_decode()

How to read multiple Integer values from a single line of input in Java?

This works fine ....

int a = nextInt(); int b = nextInt(); int c = nextInt();

Or you can read them in a loop

How to set the id attribute of a HTML element dynamically with angularjs (1.x)?

In case you came to this question but related to newer Angular version >= 2.0.

<div [id]="element.id"></div>

How to run a C# console application with the console hidden

Add this to your class to import the DLL file:

[DllImport("user32.dll")] 
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow); 

[DllImport("kernel32.dll")] 
static extern IntPtr GetConsoleWindow();

const int SW_HIDE = 0;
const int SW_SHOW = 5;

And then if you want to hide it use this command:

 var handle = GetConsoleWindow();
 ShowWindow(handle, SW_HIDE);

And if you want to show the console:

var handle = GetConsoleWindow();
ShowWindow(handle, SW_SHOW);

How to use hex() without 0x in Python?

>>> format(3735928559, 'x')
'deadbeef'

ASP.NET custom error page - Server.GetLastError() is null

OK, I found this post: http://msdn.microsoft.com/en-us/library/aa479319.aspx

with this very illustrative diagram:

diagram
(source: microsoft.com)

in essence, to get at those exception details i need to store them myself in Global.asax, for later retrieval on my custom error page.

it seems the best way is to do the bulk of the work in Global.asax, with the custom error pages handling helpful content rather than logic.

How to move columns in a MySQL table?

I had to run this for a column introduced in the later stages of a product, on 10+ tables. So wrote this quick untidy script to generate the alter command for all 'relevant' tables.

SET @NeighboringColumn = '<YOUR COLUMN SHOULD COME AFTER THIS COLUMN>';

SELECT CONCAT("ALTER TABLE `",t.TABLE_NAME,"` CHANGE COLUMN `",COLUMN_NAME,"` 
`",COLUMN_NAME,"` ", c.DATA_TYPE, CASE WHEN c.CHARACTER_MAXIMUM_LENGTH IS NOT 
NULL THEN CONCAT("(", c.CHARACTER_MAXIMUM_LENGTH, ")") ELSE "" END ,"  AFTER 
`",@NeighboringColumn,"`;")
FROM information_schema.COLUMNS c, information_schema.TABLES t
WHERE c.TABLE_SCHEMA = '<YOUR SCHEMA NAME>'
AND c.COLUMN_NAME = '<COLUMN TO MOVE>'
AND c.TABLE_SCHEMA = t.TABLE_SCHEMA
AND c.TABLE_NAME = t.TABLE_NAME
AND t.TABLE_TYPE = 'BASE TABLE'
AND @NeighboringColumn IN (SELECT COLUMN_NAME 
    FROM information_schema.COLUMNS c2 
    WHERE c2.TABLE_NAME = t.TABLE_NAME);

Number of elements in a javascript object

function count(){
    var c= 0;
    for(var p in this) if(this.hasOwnProperty(p))++c;
    return c;
}

var O={a: 1, b: 2, c: 3};

count.call(O);

missing private key in the distribution certificate on keychain

To add on to others' answers, if you don't have access to that private key anymore it's fairly simple to get back up and running:

  1. revoke your active certificate in the provisioning portal
  2. create new developer certificate (keychain access/.../request for csr...etc.)
  3. download and install a new certificate
  4. create a new provisioning profile for existing app id (on provisioning portal)
  5. download and install new provisioning profile and in the build, settings set the appropriate code signing identities

Append integer to beginning of list in Python

Note that if you are trying to do that operation often, especially in loops, a list is the wrong data structure.

Lists are not optimized for modifications at the front, and somelist.insert(0, something) is an O(n) operation.

somelist.pop(0) and del somelist[0] are also O(n) operations.

The correct data structure to use is a deque from the collections module. deques expose an interface that is similar to those of lists, but are optimized for modifications from both endpoints. They have an appendleft method for insertions at the front.

Demo:

In [1]: lst = [0]*1000
In [2]: timeit -n1000 lst.insert(0, 1)
1000 loops, best of 3: 794 ns per loop
In [3]: from collections import deque
In [4]: deq = deque([0]*1000)
In [5]: timeit -n1000 deq.appendleft(1)
1000 loops, best of 3: 73 ns per loop

java.io.StreamCorruptedException: invalid stream header: 7371007E

when I send only one object from the client to server all works well.

when I attempt to send several objects one after another on the same stream I get StreamCorruptedException.

Actually, your client code is writing one object to the server and reading multiple objects from the server. And there is nothing on the server side that is writing the objects that the client is trying to read.

How do I horizontally center a span element inside a div

One option is to give the <a> a display of inline-block and then apply text-align: center; on the containing block (remove the float as well):

div { 
    background: red;
    overflow: hidden; 
    text-align: center;
}

span a {
    background: #222;
    color: #fff;
    display: inline-block;
    /* float:left;  remove */
    margin: 10px 10px 0 0;
    padding: 5px 10px
}

http://jsfiddle.net/Adrift/cePe3/

Is it possible to disable scrolling on a ViewPager

In my case of using ViewPager 2 alpha 2 the below snippet works

viewPager.isUserInputEnabled = false

Ability to disable user input (setUserInputEnabled, isUserInputEnabled)

refer to this for more changes in viewpager2 1.0.0-alpha02

Also some changes were made latest version ViewPager 2 alpha 4

orientation and isUserScrollable attributes are no longer part of SavedState

refer to this for more changes in viewpager2#1.0.0-alpha04

Display a table/list data dynamically in MVC3/Razor from a JsonResult?

The normal way of doing it is:

  • You get the users from the database in controller.
  • You send a collection of users to the View
  • In the view to loop the list of users building the list.

You don't need a JsonResult or jQuery for this.

Check if a specific tab page is selected (active)

For whatever reason the above would not work for me. This is what did:

if (tabControl.SelectedTab.Name == "tabName" )
{
     .. do stuff
}

where tabControl.SelectedTab.Name is the name attribute assigned to the page in the tabcontrol itself.

LINQ to Entities does not recognize the method 'System.String ToString()' method, and this method cannot be translated into a store expression

Had a similar problem. Solved it by calling ToList() on the entity collection and querying the list. If the collection is small this is an option.

IQueryable<entity> pages = context.pages.ToList().Where(p=>p.serial == item.Key.ToString())

Hope this helps.

How to declare an array inside MS SQL Server Stored Procedure?

Is there a reason why you aren't using a table variable and the aggregate SUM operator, instead of a cursor? SQL excels at set-oriented operations. 99.87% of the time that you find yourself using a cursor, there's a set-oriented alternative that's more efficient:

declare @MonthsSale table
(
MonthNumber int,
MonthName varchar(9),
MonthSale decimal(18,2)
)

insert into @MonthsSale
select
    1, 'January', 100.00
union select    
    2, 'February', 200.00
union select    
    3, 'March', 300.00
union select    
    4, 'April', 400.00
union select    
    5, 'May', 500.00
union select    
    6, 'June', 600.00
union select    
    7, 'July', 700.00
union select    
    8, 'August', 800.00
union select    
    9, 'September', 900.00
union select    
    10, 'October', 1000.00
union select    
    11, 'November', 1100.00
union select    
    12, 'December', 1200.00

select * from @MonthsSale   
select SUM(MonthSale) as [TotalSales] from @MonthsSale

Using "-Filter" with a variable

You don't need quotes around the variable, so simply change this:

Get-ADComputer -Filter {name -like '$nameregex' -and Enabled -eq "true"}

into this:

Get-ADComputer -Filter {name -like $nameregex -and Enabled -eq "true"}

Note, however, that the scriptblock notation for filter statements is misleading, because the statement is actually a string, so it's better to write it as such:

Get-ADComputer -Filter "name -like '$nameregex' -and Enabled -eq 'true'"

Related. Also related.

And FTR: you're using wildcard matching here (operator -like), not regular expressions (operator -match).

How to reduce the image size without losing quality in PHP

If you are looking to reduce the size using coding itself, you can follow this code in php.

<?php 
function compress($source, $destination, $quality) {

    $info = getimagesize($source);

    if ($info['mime'] == 'image/jpeg') 
        $image = imagecreatefromjpeg($source);

    elseif ($info['mime'] == 'image/gif') 
        $image = imagecreatefromgif($source);

    elseif ($info['mime'] == 'image/png') 
        $image = imagecreatefrompng($source);

    imagejpeg($image, $destination, $quality);

    return $destination;
}

$source_img = 'source.jpg';
$destination_img = 'destination .jpg';

$d = compress($source_img, $destination_img, 90);
?>

$d = compress($source_img, $destination_img, 90);

This is just a php function that passes the source image ( i.e., $source_img ), destination image ( $destination_img ) and quality for the image that will take to compress ( i.e., 90 ).

$info = getimagesize($source);

The getimagesize() function is used to find the size of any given image file and return the dimensions along with the file type.

Replace a string in shell script using a variable

Use this instead

echo $LINE | sed -e 's/12345678/$replace/g'

this works for me just simply remove the quotes

The term "Add-Migration" is not recognized

I just had this problem too. I closed and opened VS2015 and it "fixed" the issue...

add an onclick event to a div

Is it possible to add onclick to a div and have it occur if any area of the div is clicked.

Yes … although it should be done with caution. Make sure there is some mechanism that allows keyboard access. Build on things that work

If yes then why is the onclick method not going through to my div.

You are assigning a string where a function is expected.

divTag.onclick = printWorking;

There are nicer ways to assign event handlers though, although older versions of Internet Explorer are sufficiently different that you should use a library to abstract it. There are plenty of very small event libraries and every major library jQuery) has event handling functionality.

That said, now it is 2019, older versions of Internet Explorer no longer exist in practice so you can go direct to addEventListener

How can I sort an ArrayList of Strings in Java?

You might sort the helper[] array directly:

java.util.Arrays.sort(helper, 1, helper.length);

Sorts the array from index 1 to the end. Leaves the first item at index 0 untouched.

See Arrays.sort(Object[] a, int fromIndex, int toIndex)

Way to create multiline comments in Bash?

Multiline comment in bash

: <<'END_COMMENT'
This is a heredoc (<<) redirected to a NOP command (:).
The single quotes around END_COMMENT are important,
because it disables variable resolving and command resolving
within these lines.  Without the single-quotes around END_COMMENT,
the following two $() `` commands would get executed:
$(gibberish command)
`rm -fr mydir`
comment1
comment2 
comment3
END_COMMENT

Can't load AMD 64-bit .dll on a IA 32-bit platform

If you are still getting that error after installing the 64 bit JRE, it means that the JVM running Gurobi package is still using the 32 bit JRE.

Check that you have updated the PATH and JAVA_HOME globally and in the command shell that you are using. (Maybe you just need to exit and restart it.)

Check that your command shell runs the right version of Java by running "java -version" and checking that it says it is a 64bit JRE.

If you are launching the example via a wrapper script / batch file, make sure that the script is using the right JRE. Modify as required ...

Resource leak: 'in' is never closed

The Scanner should be closed. It is a good practice to close Readers, Streams...and this kind of objects to free up resources and aovid memory leaks; and doing so in a finally block to make sure that they are closed up even if an exception occurs while handling those objects.

What does java.lang.Thread.interrupt() do?

Thread.interrupt() sets the interrupted status/flag of the target thread to true which when checked using Thread.interrupted() can help in stopping the endless thread. Refer http://www.yegor256.com/2015/10/20/interrupted-exception.html

Using $_POST to get select option value from HTML

You can access values in the $_POST array by their key. $_POST is an associative array, so to access taskOption you would use $_POST['taskOption'];.

Make sure to check if it exists in the $_POST array before proceeding though.

<form method="post" action="process.php">
  <select name="taskOption">
    <option value="first">First</option>
    <option value="second">Second</option>
    <option value="third">Third</option>
  </select>
  <input type="submit" value="Submit the form"/>
</form>

process.php

<?php
   $option = isset($_POST['taskOption']) ? $_POST['taskOption'] : false;
   if ($option) {
      echo htmlentities($_POST['taskOption'], ENT_QUOTES, "UTF-8");
   } else {
     echo "task option is required";
     exit; 
   }

How to scroll to an element?

After reading through manny forums found a really easy solution.

I use redux-form. Urgo mapped redux-from fieldToClass. Upon error I navigate to the first error on the list of syncErrors.

No refs and no third party modules. Just simple querySelector & scrollIntoView

handleToScroll = (field) => {

    const fieldToClass = {
        'vehicleIdentifier': 'VehicleIdentifier',
        'locationTags': 'LocationTags',
        'photos': 'dropzoneContainer',
        'description': 'DescriptionInput',
        'clientId': 'clientId',
        'driverLanguage': 'driverLanguage',
        'deliveryName': 'deliveryName',
        'deliveryPhone': 'deliveryPhone',
        "deliveryEmail": 'deliveryEmail',
        "pickupAndReturn": "PickupAndReturn",
        "payInCash": "payInCash",
    }

document?.querySelector(`.${fieldToClasses[field]}`)
         .scrollIntoView({ behavior: "smooth" })

}

private final static attribute vs private final attribute

If you mark this variable static then as you know, you would be requiring static methods to again access these values,this will be useful if you already think of using these variables only in static methods. If this is so then this would be the best one.

You can however make the variable now as public since no one can modify it just like "System.out", it again depends upon your intentions and what you want to achieve.

LPCSTR, LPCTSTR and LPTSTR

Quick and dirty:

LP == Long Pointer. Just think pointer or char*

C = Const, in this case, I think they mean the character string is a const, not the pointer being const.

STR is string

the T is for a wide character or char (TCHAR) depending on compile options.

Oracle : how to subtract two dates and get minutes of the result

I can handle this way:

select to_number(to_char(sysdate,'MI')) - to_number(to_char(*YOUR_DATA_VALUE*,'MI')),max(exp_time)  from ...

Or if you want to the hour just change the MI;

select to_number(to_char(sysdate,'HH24')) - to_number(to_char(*YOUR_DATA_VALUE*,'HH24')),max(exp_time)  from ...

the others don't work for me. Good luck.

Calculating width from percent to pixel then minus by pixel in LESS CSS

You can escape the calc arguments in order to prevent them from being evaluated on compilation.

Using your example, you would simply surround the arguments, like this:

calc(~'100% - 10px')

Demo : http://jsfiddle.net/c5aq20b6/


I find that I use this in one of the following three ways:

Basic Escaping

Everything inside the calc arguments is defined as a string, and is totally static until it's evaluated by the client:

LESS Input

div {
    > span {
        width: calc(~'100% - 10px');
    }
}

CSS Output

div > span {
  width: calc(100% - 10px);
}

Interpolation of Variables

You can insert a LESS variable into the string:

LESS Input

div {
    > span {
        @pad: 10px;
        width: calc(~'100% - @{pad}');
    }
}

CSS Output

div > span {
  width: calc(100% - 10px);
}

Mixing Escaped and Compiled Values

You may want to escape a percentage value, but go ahead and evaluate something on compilation:

LESS Input

@btnWidth: 40px;
div {
    > span {
        @pad: 10px;
        width: calc(~'(100% - @{pad})' - (@btnWidth * 2));
    }
}

CSS Output

div > span {
  width: calc((100% - 10px) - 80px);
}

Source: http://lesscss.org/functions/#string-functions-escape.

textarea character limit

I found a good solution that uses the maxlength attribute if the browser supports it, and falls back to an unobtrusive javascript pollyfill in unsupporting browsers.

Thanks to @Dan Tello's comment I fixed it up so it works in IE7+ as well:

HTML:

<textarea maxlength="50" id="text">This textarea has a character limit of 50.</textarea>

Javascript:

function maxLength(el) {    
    if (!('maxLength' in el)) {
        var max = el.attributes.maxLength.value;
        el.onkeypress = function () {
            if (this.value.length >= max) return false;
        };
    }
}

maxLength(document.getElementById("text"));

Demo

There is no such thing as a minlength attribute in HTML5.
For the following input types: number, range, date, datetime, datetime-local, month, time, and week (which aren't fully supported yet) use the min and max attributes.

Strip double quotes from a string in .NET

c#: "\"", thus s.Replace("\"", "")

vb/vbs/vb.net: "" thus s.Replace("""", "")

Imply bit with constant 1 or 0 in SQL Server

Unfortunately, no. You will have to cast each value individually.

How to set password for Redis?

using redis-cli:

root@server:~# redis-cli 
127.0.0.1:6379> CONFIG SET requirepass secret_password
OK

this will set password temporarily (until redis or server restart)

test password:

root@server:~# redis-cli 
127.0.0.1:6379> AUTH secret_password
OK

Update R using RStudio

I found that for me the best permanent solution to stay up-to-date under Linux was to install the R-patched project. This will keep your R installation up-to-date, and you needn't even move your packages between installations (which is described in RyanStochastic's answer).

For openSUSE, see the instructions here.

Get the data received in a Flask request

request.data

This is great to use but remember that it comes in as a string and will need iterated through.

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

This works 1) for multiline text as well 2) and even in IE9!

<div class="measureText" id="measureText">
</div>


.measureText {
  margin: 0;
  padding: 0;
  border: 0;
  font-family: Arial;
  position: fixed;
  visibility: hidden;
  height: auto;
  width: auto;
  white-space: pre-wrap;
  line-height: 100%;
}

function getTextFieldMeasure(fontSize, value) {
    const div = document.getElementById("measureText");

    // returns wrong result for multiline text with last line empty
    let arr = value.split('\n');
    if (arr[arr.length-1].length == 0) {
        value += '.';
    }

    div.innerText = value;
    div.style['font-size']= fontSize + "px";
    let rect = div.getBoundingClientRect();

    return {width: rect.width, height: rect.height};
};

Update values from one column in same table to another in SQL Server

UPDATE `tbl_user` SET `name`=concat('tbl_user.first_name','tbl_user.last_name') WHERE student_roll>965

Epoch vs Iteration when training neural networks

Many neural network training algorithms involve making multiple presentations of the entire data set to the neural network. Often, a single presentation of the entire data set is referred to as an "epoch". In contrast, some algorithms present data to the neural network a single case at a time.

"Iteration" is a much more general term, but since you asked about it together with "epoch", I assume that your source is referring to the presentation of a single case to a neural network.

Bootstrap 4 responsive tables won't take up 100% width

For some reason the responsive table in particular doesn't behave as it should. You can patch it by getting rid of display:block;

.table-responsive {
    display: table;
}

I may file a bug report.

Edit:

It is an existing bug.

Entitlements file do not match those specified in your provisioning profile.(0xE8008016)

None of the previous answers either applied or worked for me. In my case, updating the settings of the test project, as follows, fixed it:

enter image description here

Loading/Downloading image from URL on Swift

For better performance in UITableView or UICollectionView use light weight library Smart Lazy Loading You can use this lazy loading approach if you want to load images from url Asynchronous

Smart 'Lazy Loading' in UICollectionView or UITableView using NSOperation and NSOperationQueue in iOS So in this project we can download the multiple images in any View (UICollectionView or UITableView) by optimising the performance of an app by using Operation and OperationQueue for concurrency. following are the key point of this project Smart Lazy Loading: Creating image download Service. Prioritise the downloading based on the visibility of cells.

ImageDownloadService class will create a singleton instance and have NSCache instance to cache the images that have been downloaded. We have inherited the Operation class to TOperation to mauled the functionality according to our need. I think the properties of the operation subclass are pretty clear in terms of functionality. We are monitoring operations changes of state by using KVO.

Check mySQL version on Mac 10.8.5

To check your MySQL version on your mac, navigate to the directory where you installed it (default is usr/local/mysql/bin) and issue this command:

./mysql --version

Alternatively, to avoid needing to navigate to that specific dir to run the command, add its location to your path ($PATH). There's more than one way to add a dir to your $PATH (with explanations on stackoverflow and other places on how to do so), such as adding it to your ./bash_profile.

After adding the mysql bin dir to your $PATH, verify it's there by executing:

echo $PATH

Thereafter you can check your mysql version from anywhere by running (note no "./"):

mysql --version

Multi value Dictionary

Just create a Pair<TFirst, TSecond> type and use that as your value.

I have an example of one in my C# in Depth source code. Reproduced here for simplicity:

using System;
using System.Collections.Generic;

public sealed class Pair<TFirst, TSecond>
    : IEquatable<Pair<TFirst, TSecond>>
{
    private readonly TFirst first;
    private readonly TSecond second;

    public Pair(TFirst first, TSecond second)
    {
        this.first = first;
        this.second = second;
    }

    public TFirst First
    {
        get { return first; }
    }

    public TSecond Second
    {
        get { return second; }
    }

    public bool Equals(Pair<TFirst, TSecond> other)
    {
        if (other == null)
        {
            return false;
        }
        return EqualityComparer<TFirst>.Default.Equals(this.First, other.First) &&
               EqualityComparer<TSecond>.Default.Equals(this.Second, other.Second);
    }

    public override bool Equals(object o)
    {
        return Equals(o as Pair<TFirst, TSecond>);
    }

    public override int GetHashCode()
    {
        return EqualityComparer<TFirst>.Default.GetHashCode(first) * 37 +
               EqualityComparer<TSecond>.Default.GetHashCode(second);
    }
}

Only mkdir if it does not exist

mkdir -p

-p, --parents no error if existing, make parent directories as needed

Why can templates only be implemented in the header file?

It means that the most portable way to define method implementations of template classes is to define them inside the template class definition.

template < typename ... >
class MyClass
{

    int myMethod()
    {
       // Not just declaration. Add method implementation here
    }
};

Hibernate table not mapped error in HQL query

The exception message says:

Books is not mapped [SELECT COUNT(*) FROM Books]; nested exception is org.hibernate.hql.ast.QuerySyntaxException: Books is not mapped [SELECT COUNT(*) FROM Books]

Books is not mapped. That is, that there is no mapped type called Books.

And indeed, there isn't. Your mapped type is called Book. It's mapped to a table called Books, but the type is called Book. When you write HQL (or JPQL) queries, you use the names of the types, not the tables.

So, change your query to:

select count(*) from Book

Although I think it may need to be

select count(b) from Book b

If HQL doesn't support the * notation.

How to echo xml file in php

The best solution is to add to your apache .htaccess file the following line after RewriteEngine On

RewriteRule ^sitemap\.xml$ sitemap.php [L]

and then simply having a file sitemap.php in your root folder that would be normally accessible via http://www.yoursite.com/sitemap.xml, the default URL where all search engines will firstly search.

The file sitemap.php shall start with

<?php
//Saturday, 11 January 2020 @kevin

header('Content-type: text/xml');
echo '<?xml version="1.0" encoding="UTF-8"?>';
?>
<urlset
      xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"
      xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9
            http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">

<url>
  <loc>https://www.yoursite.com/</loc>
  <lastmod>2020-01-08T13:06:14+00:00</lastmod>
  <priority>1.00</priority>
</url>


</urlset>

it works :)

How to write log to file

Building on Allison and Deepak's answer, I started using logrus and really like it:

var log = logrus.New()

func init() {

    // log to console and file
    f, err := os.OpenFile("crawler.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0666)
    if err != nil {
        log.Fatalf("error opening file: %v", err)
    }
    wrt := io.MultiWriter(os.Stdout, f)

    log.SetOutput(wrt)
}

I have a defer f.Close() in the main function

How to troubleshoot an "AttributeError: __exit__" in multiproccesing in Python?

It is not the asker's problem in this instance but the first troubleshooting step for a generic "AttributeError: __exit__" should be making sure the brackets are there, e.g.

with SomeContextManager() as foo:
    #works because a new object is referenced...

not

with SomeContextManager as foo:
    #AttributeError because the class is referenced

Catches me out from time to time and I end up here -__-

PHP exec() vs system() vs passthru()

The previous answers seem all to be a little confusing or incomplete, so here is a table of the differences...

+----------------+-----------------+----------------+----------------+
|    Command     | Displays Output | Can Get Output | Gets Exit Code |
+----------------+-----------------+----------------+----------------+
| system()       | Yes (as text)   | Last line only | Yes            |
| passthru()     | Yes (raw)       | No             | Yes            |
| exec()         | No              | Yes (array)    | Yes            |
| shell_exec()   | No              | Yes (string)   | No             |
| backticks (``) | No              | Yes (string)   | No             |
+----------------+-----------------+----------------+----------------+
  • "Displays Output" means it streams the output to the browser (or command line output if running from a command line).
  • "Can Get Output" means you can get the output of the command and assign it to a PHP variable.
  • The "exit code" is a special value returned by the command (also called the "return status"). Zero usually means it was successful, other values are usually error codes.

Other misc things to be aware of:

  • The shell_exec() and the backticks operator do the same thing.
  • There are also proc_open() and popen() which allow you to interactively read/write streams with an executing command.
  • Add "2>&1" to the command string if you also want to capture/display error messages.
  • Use escapeshellcmd() to escape command arguments that may contain problem characters.
  • If passing an $output variable to exec() to store the output, if $output isn't empty, it will append the new output to it. So you may need to unset($output) first.

Can't create a docker image for COPY failed: stat /var/lib/docker/tmp/docker-builder error

The following structure in docker-compose.yaml will allow you to have the Dockerfile in a subfolder from the root:

version: '3'
services:
  db:
    image: postgres:11
    environment:
      - PGDATA=/var/lib/postgresql/data/pgdata
    volumes:
      - postgres-data:/var/lib/postgresql/data
    ports:
      - 127.0.0.1:5432:5432
  **web:
    build: 
      context: ".."
      dockerfile: dockerfiles/Dockerfile**
    command: ...
...

Then, in your Dockerfile, which is in the same directory as docker-compose.yaml, you can do the following:

ENV APP_HOME /home

RUN mkdir -p ${APP_HOME}

# Copy the file to the directory in the container
COPY test.json ${APP_HOME}/test.json
COPY test.py ${APP_HOME}/test.py

# Browse to that directory created above
WORKDIR ${APP_HOME}

You can then run docker-compose from the parent directory like:

docker-compose -f .\dockerfiles\docker-compose.yaml build --no-cache

Before and After Suite execution hook in jUnit 4.x

The only way I think then to get the functionality you want would be to do something like

import junit.framework.Test;  
import junit.framework.TestResult;  
import junit.framework.TestSuite;  

public class AllTests {  
    public static Test suite() {  
        TestSuite suite = new TestSuite("TestEverything");  
        //$JUnit-BEGIN$  
        suite.addTestSuite(TestOne.class);  
        suite.addTestSuite(TestTwo.class);  
        suite.addTestSuite(TestThree.class);  
        //$JUnit-END$  
     }  

     public static void main(String[] args)  
     {  
        AllTests test = new AllTests();  
        Test testCase = test.suite();  
        TestResult result = new TestResult();  
        setUp();  
        testCase.run(result);  
        tearDown();  
     }  
     public void setUp() {}  
     public void tearDown() {}  
} 

I use something like this in eclipse, so I'm not sure how portable it is outside of that environment

Fitting a density curve to a histogram in R

Such thing is easy with ggplot2

library(ggplot2)
dataset <- data.frame(X = c(rep(65, times=5), rep(25, times=5), 
                            rep(35, times=10), rep(45, times=4)))
ggplot(dataset, aes(x = X)) + 
  geom_histogram(aes(y = ..density..)) + 
  geom_density()

or to mimic the result from Dirk's solution

ggplot(dataset, aes(x = X)) + 
  geom_histogram(aes(y = ..density..), binwidth = 5) + 
  geom_density()

Understanding the main method of python

If you import the module (.py) file you are creating now from another python script it will not execute the code within

if __name__ == '__main__':
    ...

If you run the script directly from the console, it will be executed.

Python does not use or require a main() function. Any code that is not protected by that guard will be executed upon execution or importing of the module.

This is expanded upon a little more at python.berkely.edu

Add floating point value to android resources/values

I found a solution, which works, but does result in a Warning (WARN/Resources(268): Converting to float: TypedValue{t=0x3/d=0x4d "1.2" a=2 r=0x7f06000a}) in LogCat.

<resources>
    <string name="text_line_spacing">1.2</string>
</resources>

<android:lineSpacingMultiplier="@string/text_line_spacing"/>

how to concatenate two dictionaries to create a new one in Python?

d4 = dict(d1.items() + d2.items() + d3.items())

alternatively (and supposedly faster):

d4 = dict(d1)
d4.update(d2)
d4.update(d3)

Previous SO question that both of these answers came from is here.

How to center align the ActionBar title in Android?

It works nicely.

activity = (AppCompatActivity) getActivity();

activity.getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);

LayoutInflater inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = inflater.inflate(R.layout.custom_actionbar, null);

ActionBar.LayoutParams p = new ActionBar.LayoutParams(
        ViewGroup.LayoutParams.MATCH_PARENT,
        ViewGroup.LayoutParams.MATCH_PARENT,
        Gravity.CENTER);

((TextView) v.findViewById(R.id.title)).setText(FRAGMENT_TITLE);

activity.getSupportActionBar().setCustomView(v, p);
activity.getSupportActionBar().setDisplayShowTitleEnabled(true);
activity.getSupportActionBar().setDisplayHomeAsUpEnabled(true);

Below layout of custom_actionbar:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <TextView
        android:id="@+id/title"
        android:layout_width="wrap_content"
        android:text="Example"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:ellipsize="end"
        android:maxLines="1"
        android:textAppearance="?android:attr/textAppearanceMedium"
        android:textColor="@color/colorBlack" />

</RelativeLayout>

How to check if an object is an array?

Other methods also exist to check but I prefer the following method as my best to check (as you can easily check types of other objects).

> a = [1, 2]
[ 1, 2 ]
>
> Object.prototype.toString.call(a).slice(8,).replace(/\]$/, '')
'Array'
>
> Object.prototype.toString.call([]).slice(8,-1) // best approach
'Array'

Explanation (with simple examples on Node REPL)»

> o = {'ok': 1}
{ ok: 1 }
> a = [1, 2]
[ 1, 2 ]
> typeof o
'object'
> typeof a
'object'
>
> Object.prototype.toString.call(o)
'[object Object]'
> Object.prototype.toString.call(a)
'[object Array]'
>

Object or Array »

> Object.prototype.toString.call(o).slice(8,).replace(/\]$/, '')
'Object'
>
> Object.prototype.toString.call(a).slice(8,).replace(/\]$/, '')
'Array'
>

Null or Undefined »

> Object.prototype.toString.call(undefined).slice(8,).replace(/\]$/, '')
'Undefined'
> Object.prototype.toString.call(null).slice(8,).replace(/\]$/, '')
'Null'
>

String »

> Object.prototype.toString.call('ok').slice(8,).replace(/\]$/, '')
'String'

Number »

> Object.prototype.toString.call(19).slice(8,).replace(/\]$/, '')
'Number'
> Object.prototype.toString.call(19.0).slice(8,).replace(/\]$/, '')
'Number'
> Object.prototype.toString.call(19.7).slice(8,).replace(/\]$/, '')
'Number'
>

I appreciate @mpen's suggestion to use -1 in place of regular expression as follows.

> Object.prototype.toString.call(12).slice(8,-1)
'Number'
>
> Object.prototype.toString.call(12.0).slice(8,-1)
'Number'
>
> Object.prototype.toString.call([]).slice(8,-1)
'Array'
> Object.prototype.toString.call({}).slice(8,-1)
'Object'
>
> Object.prototype.toString.call('').slice(8,-1)
'String'
>

How to remove ASP.Net MVC Default HTTP Headers?

As described in Cloaking your ASP.NET MVC Web Application on IIS 7, you can turn off the X-AspNet-Version header by applying the following configuration section to your web.config:

<system.web> 
  <httpRuntime enableVersionHeader="false"/> 
</system.web>

and remove the X-AspNetMvc-Version header by altering your Global.asax.cs as follows:

protected void Application_Start() 
{ 
    MvcHandler.DisableMvcResponseHeader = true; 
}

As described in Custom Headers You can remove the "X-Powered-By" header by applying the following configuration section to your web.config:

<system.webServer>
   <httpProtocol>
      <customHeaders>
         <clear />
      </customHeaders>
   </httpProtocol>
</system.webServer>

There is no easy way to remove the "Server" response header via configuration, but you can implement an HttpModule to remove specific HTTP Headers as described in Cloaking your ASP.NET MVC Web Application on IIS 7 and in how-to-remove-server-x-aspnet-version-x-aspnetmvc-version-and-x-powered-by-from-the-response-header-in-iis7.

What are .NET Assemblies?

physical collection of Class, interface, enum etc which is in IL code. Which can be .EXE or .DLL file .EXE is executable file and .DLL can dynamically used in any .net Supported language.

How to convert a HTMLElement to a string

There's a tagName property, and a attributes property as well:

var element = document.getElementById("wtv");
var openTag = "<"+element.tagName;
for (var i = 0; i < element.attributes.length; i++) {
    var attrib = element.attributes[i];
    openTag += " "+attrib.name + "=" + attrib.value;
}
openTag += ">";
alert(openTag);

See also How to iterate through all attributes in an HTML element? (I did!)

To get the contents between the open and close tags you could probably use innerHTML if you don't want to iterate over all the child elements...

alert(element.innerHTML);

... and then get the close tag again with tagName.

var closeTag = "</"+element.tagName+">";
alert(closeTag);

React: Expected an assignment or function call and instead saw an expression

Not sure about solutions but a temporary workaround is to ask eslint to ignore it by adding the following on top of the problem line.

// eslint-disable-next-line @typescript-eslint/no-unused-expressions

video as site background? HTML 5

I might have a solution for the video as background, stretched to the browser-width or height, (but the video will still preserve the aspect ratio, couldnt find a solution for that yet.):

Put the video right after the body-tag with style="width:100%;". Right afterwords, put a "bodydummy"-tag:

<body>
<video id="bgVideo" autoplay poster="videos/poster.png">
    <source src="videos/test-h264-640x368-highqual-winff.mp4" type="video/mp4"/>
    <source src="videos/test-640x368-webmvp8-miro.webm" type="video/webm"/>
    <source src="videos/test-640x368-theora-miro.ogv" type="video/ogg"/>    
</video>

<img id="bgImg" src="videos/poster.png" />

<!-- This image stretches exactly to the browser width/height and lies behind the video-->

<div id="bodyDummy">

Put all your content inside the bodydummy-div and put the z-indexes correctly in CSS like this:

#bgImg{ 
    position: absolute;
    top: 0;
    left: 0;
    border: 0;
    z-index: 1;
    width: 100%;
    height: 100%;
}

#bgVideo{ 
    position: absolute;
    top: 0;
    left: 0;
    border: 0;
    z-index: 2;
    width: 100%;
    height: 100%;
}

#bodyDummy{ 
    position: absolute;
    top: 0;
    left: 0;
    z-index: 3;
    overflow: auto;
    width: 100%;
    height: 100%;
}

Hope I could help. Let me know when you could find a solution that the video does not maintain the aspect ratio, so it could fill the whole browser window so we do not have to put a bgimage.

How to set width of a p:column in a p:dataTable in PrimeFaces 3.0?

Addition to @BalusC 's answer. You also need to set width of headers. In my case, below css can only apply to my table's column width.

.myTable td:nth-child(1),.myTable th:nth-child(1) {
   width: 20px;
}

Assign value from successful promise resolve to external variable

The then() method returns a Promise. It takes two arguments, both are callback functions for the success and failure cases of the Promise. the promise object itself doesn't give you the resolved data directly, the interface of this object only provides the data via callbacks supplied. So, you have to do this like this:

getFeed().then(function(data) { vm.feed = data;});

The then() function returns the promise with a resolved value of the previous then() callback, allowing you the pass the value to subsequent callbacks:

promiseB = promiseA.then(function(result) {
  return result + 1;
});

// promiseB will be resolved immediately after promiseA is resolved
// and its value will be the result of promiseA incremented by 1

Hibernate: Automatically creating/updating the db tables based on entity classes

You might try changing this line in your persistence.xml from

<property name="hbm2ddl.auto" value="create"/>

to:

<property name="hibernate.hbm2ddl.auto" value="update"/>

This is supposed to maintain the schema to follow any changes you make to the Model each time you run the app.

Got this from JavaRanch

Convert UTC dates to local time in PHP

date() and localtime() both use the local timezone for the server unless overridden; you can override the timezone used with date_default_timezone_set().

http://www.php.net/manual/en/function.date-default-timezone-set.php

http://us3.php.net/manual/en/function.date.php

http://php.net/manual/en/function.localtime.php

The HTTP request is unauthorized with client authentication scheme 'Ntlm' The authentication header received from the server was 'NTLM'

I have had this issue before.

client.ClientCredentials.Windows.AllowedImpersonationLevel = TokenImpersonationLevel.Impersonation;

do this against your wcf proxy before making the call.

How do you join on the same table, twice, in mysql?

Given the following tables..

Domain Table
dom_id | dom_url

Review Table
rev_id | rev_dom_from | rev_dom_for

Try this sql... (It's pretty much the same thing that Stephen Wrighton wrote above) The trick is that you are basically selecting from the domain table twice in the same query and joining the results.

Select d1.dom_url, d2.dom_id from
review r, domain d1, domain d2
where d1.dom_id = r.rev_dom_from
and d2.dom_id = r.rev_dom_for

If you are still stuck, please be more specific with exactly it is that you don't understand.

Force index use in Oracle

There is an appropriate index on column_having_index, and its use actually increase performance, but Oracle didn't use it...
You should gather statistics on your table to let optimizer see that index access can help. Using direct hint is not a good practice.

Use basic authentication with jQuery and Ajax

The examples above are a bit confusing, and this is probably the best way:

$.ajaxSetup({
  headers: {
    'Authorization': "Basic " + btoa(USERNAME + ":" + PASSWORD)
  }
});

I took the above from a combination of Rico and Yossi's answer.

The btoa function Base64 encodes a string.

What’s the best way to check if a file exists in C++? (cross platform)

Be careful of race conditions: if the file disappears between the "exists" check and the time you open it, your program will fail unexpectedly.

It's better to go and open the file, check for failure and if all is good then do something with the file. It's even more important with security-critical code.

Details about security and race conditions: http://www.ibm.com/developerworks/library/l-sprace.html

Best way to remove items from a collection

What type is the collection? If it's List, you can use the helpful "RemoveAll":

int cnt = workspace.RoleAssignments
                      .RemoveAll(spa => spa.Member.Name == shortName)

(This works in .NET 2.0. Of course, if you don't have the newer compiler, you'll have to use "delegate (SPRoleAssignment spa) { return spa.Member.Name == shortName; }" instead of the nice lambda syntax.)

Another approach if it's not a List, but still an ICollection:

   var toRemove = workspace.RoleAssignments
                              .FirstOrDefault(spa => spa.Member.Name == shortName)
   if (toRemove != null) workspace.RoleAssignments.Remove(toRemove);

This requires the Enumerable extension methods. (You can copy the Mono ones in, if you are stuck on .NET 2.0). If it's some custom collection that cannot take an item, but MUST take an index, some of the other Enumerable methods, such as Select, pass in the integer index for you.

Android : How to read file in bytes?

If you want to use a the openFileInput method from a Context for this, you can use the following code.

This will create a BufferArrayOutputStream and append each byte as it's read from the file to it.

/**
 * <p>
 *     Creates a InputStream for a file using the specified Context
 *     and returns the Bytes read from the file.
 * </p>
 *
 * @param context The context to use.
 * @param file The file to read from.
 * @return The array of bytes read from the file, or null if no file was found.
 */
public static byte[] read(Context context, String file) throws IOException {
    byte[] ret = null;

    if (context != null) {
        try {
            InputStream inputStream = context.openFileInput(file);
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

            int nextByte = inputStream.read();
            while (nextByte != -1) {
                outputStream.write(nextByte);
                nextByte = inputStream.read();
            }

            ret = outputStream.toByteArray();

        } catch (FileNotFoundException ignored) { }
    }

    return ret;
}

JavaScript sleep/wait before continuing

JS does not have a sleep function, it has setTimeout() or setInterval() functions.

If you can move the code that you need to run after the pause into the setTimeout() callback, you can do something like this:

//code before the pause
setTimeout(function(){
    //do what you need here
}, 2000);

see example here : http://jsfiddle.net/9LZQp/

This won't halt the execution of your script, but due to the fact that setTimeout() is an asynchronous function, this code

console.log("HELLO");
setTimeout(function(){
    console.log("THIS IS");
}, 2000);
console.log("DOG");

will print this in the console:

HELLO
DOG
THIS IS

(note that DOG is printed before THIS IS)


You can use the following code to simulate a sleep for short periods of time:

function sleep(milliseconds) {
  var start = new Date().getTime();
  for (var i = 0; i < 1e7; i++) {
    if ((new Date().getTime() - start) > milliseconds){
      break;
    }
  }
}

now, if you want to sleep for 1 second, just use:

sleep(1000);

example: http://jsfiddle.net/HrJku/1/

please note that this code will keep your script busy for n milliseconds. This will not only stop execution of Javascript on your page, but depending on the browser implementation, may possibly make the page completely unresponsive, and possibly make the entire browser unresponsive. In other words this is almost always the wrong thing to do.

How to add 20 minutes to a current date?

Use .getMinutes() to get the current minutes, then add 20 and use .setMinutes() to update the date object.

var twentyMinutesLater = new Date();
twentyMinutesLater.setMinutes(twentyMinutesLater.getMinutes() + 20);

How do I create a user with the same privileges as root in MySQL/MariaDB?

% mysql --user=root mysql
CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost' WITH GRANT OPTION;
CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass';
GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%' WITH GRANT OPTION;
CREATE USER 'admin'@'localhost';
GRANT RELOAD,PROCESS ON *.* TO 'admin'@'localhost';
CREATE USER 'dummy'@'localhost';
FLUSH PRIVILEGES;

Instantly detect client disconnection from server socket

You can also check the .IsConnected property of the socket if you were to poll.

How to watch and compile all TypeScript sources?

you can watch all files like this

tsc *.ts --watch

How to make a class property?

If you define classproperty as follows, then your example works exactly as you requested.

class classproperty(object):
    def __init__(self, f):
        self.f = f
    def __get__(self, obj, owner):
        return self.f(owner)

The caveat is that you can't use this for writable properties. While e.I = 20 will raise an AttributeError, Example.I = 20 will overwrite the property object itself.

Warn user before leaving web page with unsaved changes

Check out the JavaScript onbeforeunload event. It's non-standard JavaScript introduced by Microsoft, however it works in most browsers and their onbeforeunload documentation has more information and examples.

Why I'm getting 'Non-static method should not be called statically' when invoking a method in a Eloquent model?

For use the syntax like return Post::getAll(); you should have a magic function __callStatic in your class where handle all static calls:

public static function __callStatic($method, $parameters)
{
    return (new static)->$method(...$parameters);
}

Getting values from query string in an url using AngularJS $location

My fix is more simple, create a factory, and implement as one variable. For example

_x000D_
_x000D_
angular.module('myApp', [])_x000D_
_x000D_
// This a searchCustom factory. Copy the factory and implement in the controller_x000D_
.factory("searchCustom", function($http,$log){    _x000D_
    return {_x000D_
        valuesParams : function(params){_x000D_
            paramsResult = [];_x000D_
            params = params.replace('(', '').replace(')','').split("&");_x000D_
            _x000D_
            for(x in params){_x000D_
                paramsKeyTmp = params[x].split("=");_x000D_
                _x000D_
                // Si el parametro esta disponible anexamos al vector paramResult_x000D_
                if (paramsKeyTmp[1] !== '' && paramsKeyTmp[1] !== ' ' && _x000D_
                    paramsKeyTmp[1] !== null){          _x000D_
                    _x000D_
                    paramsResult.push(params[x]);_x000D_
                }_x000D_
            }_x000D_
            _x000D_
            return paramsResult;_x000D_
        }_x000D_
    }_x000D_
})_x000D_
_x000D_
.controller("SearchController", function($scope, $http,$routeParams,$log,searchCustom){_x000D_
    $ctrl = this;_x000D_
    _x000D_
    var valueParams = searchCustom.valuesParams($routeParams.value);_x000D_
    valueParams = valueParams.join('&');_x000D_
_x000D_
    $http({_x000D_
        method : "GET",_x000D_
        url: webservice+"q?"+valueParams_x000D_
    }).then( function successCallback(response){_x000D_
        data = response.data;_x000D_
        $scope.cantEncontrados = data.length; _x000D_
        $scope.dataSearch = data;_x000D_
        _x000D_
    } , function errorCallback(response){_x000D_
        console.log(response.statusText);_x000D_
    })_x000D_
      _x000D_
})
_x000D_
<html>_x000D_
<head>_x000D_
</head>_x000D_
<body ng-app="myApp">_x000D_
<div ng-controller="SearchController">_x000D_
<form action="#" >_x000D_
                          _x000D_
                            _x000D_
                            <input ng-model="param1" _x000D_
                                   placeholder="param1" />_x000D_
                            _x000D_
                            <input  ng-model="param2" _x000D_
                                    placeholder="param2"/>_x000D_
                        _x000D_
<!-- Implement in the html code _x000D_
(param1={{param1}}&param2={{param2}}) -> this is a one variable, the factory searchCustom split and restructure in the array params_x000D_
-->          _x000D_
                        <a href="#seach/(param1={{param1}}&param2={{param2}})">_x000D_
                            <buttom ng-click="searchData()" >Busqueda</buttom>_x000D_
                        </a>_x000D_
                    </form> _x000D_
</div>_x000D_
</body>
_x000D_
_x000D_
_x000D_

Correct way to handle conditional styling in React

 <div style={{ visibility: this.state.driverDetails.firstName != undefined? 'visible': 'hidden'}}></div>

Checkout the above code. That will do the trick.

How to get current local date and time in Kotlin

You can get current year, month, day etc from a calendar instance

val c = Calendar.getInstance()

val year = c.get(Calendar.YEAR)
val month = c.get(Calendar.MONTH)
val day = c.get(Calendar.DAY_OF_MONTH)

val hour = c.get(Calendar.HOUR_OF_DAY)
val minute = c.get(Calendar.MINUTE)

If you need it as a LocalDateTime, simply create it by using the parameters you got above

val myLdt = LocalDateTime.of(year, month, day, ... )

Twitter Bootstrap - add top space between rows

In Bootstrap 4 alpha+ you can use this

class margin-bottom-5

The classes are named using the format: {property}-{sides}-{size}

What is the difference between onBlur and onChange attribute in HTML?

The onBlur event is fired when you have moved away from an object without necessarily having changed its value.

The onChange event is only called when you have changed the value of the field and it loses focus.

You might want to take a look at quirksmode's intro to events. This is a great place to get info on what's going on in your browser when you interact with it. His book is good too.

Disable scrolling on `<input type=number>`

Easiest solution is to add onWheel={ event => event.currentTarget.blur() }} on input itself.

Default Xmxsize in Java 8 (max heap size)

It varies on implementation and version, but usually it depends on the VM used (e.g. client or server, see -client and -server parameters) and on your system memory.

Often for client the default value is 1/4th of your physical memory or 1GB (whichever is smaller).

Also Java configuration options (command line parameters) can be "outsourced" to environment variables including the -Xmx, which can change the default (meaning specify a new default). Specifically the JAVA_TOOL_OPTIONS environment variable is checked by all Java tools and used if exists (more details here and here).

You can run the following command to see default values:

java -XX:+PrintFlagsFinal -version

It gives you a loooong list, -Xmx is in MaxHeapSize, -Xms is in InitialHeapSize. Filter your output (e.g. |grep on linux) or save it in a file so you can search in it.

Performance differences between ArrayList and LinkedList

Ignore this answer for now. The other answers, particularly that of aix, are mostly correct. Over the long term they're the way to bet. And if you have enough data (on one benchmark on one machine, it seemed to be about one million entries) ArrayList and LinkedList do currently work as advertized. However, there are some fine points that apply in the early 21st century.

Modern computer technology seems, by my testing, to give an enormous edge to arrays. Elements of an array can be shifted and copied at insane speeds. As a result arrays and ArrayList will, in most practical situations, outperform LinkedList on inserts and deletes, often dramatically. In other words, ArrayList will beat LinkedList at its own game.

The downside of ArrayList is it tends to hang onto memory space after deletions, where LinkedList gives up space as it gives up entries.

The bigger downside of arrays and ArrayList is they fragment free memory and overwork the garbage collector. As an ArrayList expands, it creates new, bigger arrays, copies the old array to the new one, and frees the old one. Memory fills with big contiguous chunks of free memory that are not big enough for the next allocation. Eventually there's no suitable space for that allocation. Even though 90% of memory is free, no individual piece is big enough to do the job. The GC will work frantically to move things around, but if it takes too long to rearrange the space, it will throw an OutOfMemoryException. If it doesn't give up, it can still slow your program way down.

The worst of it is this problem can be hard to predict. Your program will run fine one time. Then, with a bit less memory available, with no warning, it slows or stops.

LinkedList uses small, dainty bits of memory and GC's love it. It still runs fine when you're using 99% of your available memory.

So in general, use ArrayList for smaller sets of data that are not likely to have most of their contents deleted, or when you have tight control over creation and growth. (For instance, creating one ArrayList that uses 90% of memory and using it without filling it for the duration of the program is fine. Continually creating and freeing ArrayList instances that use 10% of memory will kill you.) Otherwise, go with LinkedList (or a Map of some sort if you need random access). If you have very large collections (say over 100,000 elements), no concerns about the GC, and plan lots of inserts and deletes and no random access, run a few benchmarks to see what's fastest.

php pdo: get the columns name of a table

A very useful solution here for SQLite3. Because the OP does not indicate MySQL specifically and there was a failed attempt to use some solutions on SQLite.

    $table_name = 'content_containers';
    $container_result = $connect->query("PRAGMA table_info(" . $table_name . ")");
    $container_result->setFetchMode(PDO::FETCH_ASSOC);


    foreach ($container_result as $conkey => $convalue)
    {

        $elements[$convalue['name']] = $convalue['name'];

    }

This returns an array. Since this is a direct information dump you'll need to iterate over and filter the results to get something like this:

Array
(
    [ccid] => ccid
    [administration_title] => administration_title
    [content_type_id] => content_type_id
    [author_id] => author_id
    [date_created] => date_created
    [language_id] => language_id
    [publish_date] => publish_date
    [status] => status
    [relationship_ccid] => relationship_ccid
    [url_alias] => url_alias
)

This is particularly nice to have when the table is empty.

Binding ItemsSource of a ComboBoxColumn in WPF DataGrid

the bast way i use i bind the textblock and combobox to same property and this property should support notifyPropertyChanged.

i used relativeresource to bind to parent view datacontext which is usercontrol to go up datagrid level in binding because in this case the datagrid will search in object that you used in datagrid.itemsource

<DataGridTemplateColumn Header="your_columnName">
     <DataGridTemplateColumn.CellTemplate>
          <DataTemplate>
             <TextBlock Text="{Binding RelativeSource={RelativeSource AncestorType={x:Type UserControl}}, Path=DataContext.SelectedUnit.Name, Mode=TwoWay}" />
           </DataTemplate>
     </DataGridTemplateColumn.CellTemplate>
     <DataGridTemplateColumn.CellEditingTemplate>
           <DataTemplate>
            <ComboBox DisplayMemberPath="Name"
                      IsEditable="True"
                      ItemsSource="{Binding RelativeSource={RelativeSource AncestorType={x:Type UserControl}}, Path=DataContext.UnitLookupCollection}"
                       SelectedItem="{Binding RelativeSource={RelativeSource AncestorType={x:Type UserControl}}, Path=DataContext.SelectedUnit, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                      SelectedValue="{Binding UnitId, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"
                      SelectedValuePath="Id" />
            </DataTemplate>
    </DataGridTemplateColumn.CellEditingTemplate>
</DataGridTemplateColumn>

Converting a JS object to an array using jQuery

How about jQuery.makeArray(obj)

This is how I did it in my app.

How to use PrimeFaces p:fileUpload? Listener method is never invoked or UploadedFile is null / throws an error / not usable

You are using prettyfaces too? Then set dispatcher to FORWARD:

<filter-mapping>
   <filter-name>PrimeFaces FileUpload Filter</filter-name>
   <servlet-name>Faces Servlet</servlet-name>
   <dispatcher>FORWARD</dispatcher>
</filter-mapping>

Running windows shell commands with python

import subprocess
result = []
win_cmd = 'ipconfig'(curr_user,filename,ip_address)
process = subprocess.Popen(win_cmd,
shell=True,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE )
for line in process.stdout:
    print line
result.append(line)
errcode = process.returncode
for line in result:
    print line

HRESULT: 0x800A03EC on Worksheet.range

EDIT: THIS IS WAY BETTER!!! You don't need that old function, sorry. Just do as follows:

Microsoft.Office.Interop.Excel.Range neededRange = currentWS.Range["A1", ((Microsoft.Office.Interop.Excel.Range)currentWS.Cells[nRowCount, nColumnCount])];

That should work like a charm. And for future reference, put the relevant code that you are using inside of your question. Don't make people ask for it in comments. I imagine that's why you got downvoted.

What is the difference between visibility:hidden and display:none?

In addition to all other answers, there's an important difference for IE8: If you use display:none and try to get the element's width or height, IE8 returns 0 (while other browsers will return the actual sizes). IE8 returns correct width or height only for visibility:hidden.

Can Windows Containers be hosted on linux?

Unlike Virtualization, containerization uses the same host os. So the container built on linux can not be run on windows and vice versa.

In windows, you have to take help of virtuallization (using Hyper-v) to have same os as your containers's os and then you should be able to run the same.

Docker for windows is similar app which is built on Hyper-v and helps in running linux docker container on windows. But as far as I know, there is nothing as such which helps run windows containers on linux.

View tabular file such as CSV from command line

You can install csvtool (on Ubuntu) via

sudo apt-get install csvtool

and then run:

csvtool readable filename | view -

This will make it nice and pretty inside of a read-only vim instance, even if you have some cells with very long values.

Applying an ellipsis to multiline text

May be this can help you guys. Multi Line Ellipses with tooltip hover. https://codepen.io/Anugraha123/pen/WOBdOb

<div>
     <p class="cards-values">Lorem ipsum dolor sit amet,   consectetur adipiscing elit. Nunc aliquet lorem commodo, semper mauris nec, suscipit nisi. Nullam laoreet massa sit amet leo malesuada imperdiet eu a augue. Sed ac diam quis ante congue volutpat non vitae sem. Vivamus a felis id dui aliquam tempus
      </p>
      <span class="tooltip"></span>
</div>

Removing duplicates from a SQL query (not just "use distinct")

Arbitrarily choosing to keep the minimum PIC_ID. Also, avoid using the implicit join syntax.

SELECT U.NAME, MIN(P.PIC_ID)
    FROM USERS U
        INNER JOIN POSTINGS P1
            ON U.EMAIL_ID = P1.EMAIL_ID
        INNER JOIN PICTURES P
            ON P1.PIC_ID = P.PIC_ID
    WHERE P.CAPTION LIKE '%car%'
    GROUP BY U.NAME;

How to develop or migrate apps for iPhone 5 screen resolution?

Peter, you should really take a look at Canappi, it does all that for you, all you have to do is specify the layout as such:

button mySubmitButton 'Sumbit' (100,100,100,30 + 0,88,0,0) { ... }

From there Canappi will generate the correct objective-c code that detects the device the app is running on and will use:

(100,100,100,30) for iPhone4
(100,**188**,100,30) for iPhone 5

Canappi works like Interface Builder and Story Board combined, except that it is in a textual form. If you already have XIB files, you can convert them so you don't have to recreate the entire UI from scratch.

How to select Python version in PyCharm?

File -> Settings

Preferences->Project Interpreter->Python Interpreters

If it's not listed add it.

enter image description here

Escape double quote in VB string

Did you try using double-quotes? Regardless, no one in 2011 should be limited by the native VB6 shell command. Here's a function that uses ShellExecuteEx, much more versatile.

Option Explicit

Private Const SEE_MASK_DEFAULT = &H0

Public Enum EShellShowConstants
        essSW_HIDE = 0
        essSW_SHOWNORMAL = 1
        essSW_SHOWMINIMIZED = 2
        essSW_MAXIMIZE = 3
        essSW_SHOWMAXIMIZED = 3
        essSW_SHOWNOACTIVATE = 4
        essSW_SHOW = 5
        essSW_MINIMIZE = 6
        essSW_SHOWMINNOACTIVE = 7
        essSW_SHOWNA = 8
        essSW_RESTORE = 9
        essSW_SHOWDEFAULT = 10
End Enum

Private Type SHELLEXECUTEINFO
        cbSize        As Long
        fMask         As Long
        hwnd          As Long
        lpVerb        As String
        lpFile        As String
        lpParameters  As String
        lpDirectory   As String
        nShow         As Long
        hInstApp      As Long
        lpIDList      As Long     'Optional
        lpClass       As String   'Optional
        hkeyClass     As Long     'Optional
        dwHotKey      As Long     'Optional
        hIcon         As Long     'Optional
        hProcess      As Long     'Optional
End Type

Private Declare Function ShellExecuteEx Lib "shell32.dll" Alias "ShellExecuteExA" (lpSEI As SHELLEXECUTEINFO) As Long

Public Function ExecuteProcess(ByVal FilePath As String, ByVal hWndOwner As Long, ShellShowType As EShellShowConstants, Optional EXEParameters As String = "", Optional LaunchElevated As Boolean = False) As Boolean
    Dim SEI As SHELLEXECUTEINFO

    On Error GoTo Err

    'Fill the SEI structure
    With SEI
        .cbSize = Len(SEI)                  ' Bytes of the structure
        .fMask = SEE_MASK_DEFAULT           ' Check MSDN for more info on Mask
        .lpFile = FilePath                  ' Program Path
        .nShow = ShellShowType              ' How the program will be displayed
        .lpDirectory = PathGetFolder(FilePath)
        .lpParameters = EXEParameters       ' Each parameter must be separated by space. If the lpFile member specifies a document file, lpParameters should be NULL.
        .hwnd = hWndOwner                   ' Owner window handle

        ' Determine launch type (would recommend checking for Vista or greater here also)
        If LaunchElevated = True Then ' And m_OpSys.IsVistaOrGreater = True
            .lpVerb = "runas"
        Else
            .lpVerb = "Open"
        End If
    End With

     ExecuteProcess = ShellExecuteEx(SEI)   ' Execute the program, return success or failure

    Exit Function
Err:
    ' TODO: Log Error
    ExecuteProcess = False
End Function

Private Function PathGetFolder(psPath As String) As String
    On Error Resume Next
    Dim lPos As Long
    lPos = InStrRev(psPath, "\")
    PathGetFolder = Left$(psPath, lPos - 1)
End Function

Unable to start the mysql server in ubuntu

I think this is because you are using client software and not the server.

  • mysql is client
  • mysqld is the server

Try: sudo service mysqld start

To check that service is running use: ps -ef | grep mysql | grep -v grep.

Uninstalling:

sudo apt-get purge mysql-server
sudo apt-get autoremove
sudo apt-get autoclean

Re-Installing:

sudo apt-get update
sudo apt-get install mysql-server

Backup entire folder before doing this:

sudo rm /etc/apt/apt.conf.d/50unattended-upgrades*
sudo apt-get update
sudo apt-get upgrade

google console error `OR-IEH-01`

It looks like your Google Play registration payment didn’t process. This can happen sometimes if a card has expired, the credit card or credit card verification (CVC) number was entered incorrectly, or if your billing address doesn't match the address in your Google Payments account.

Here’s how you can find the details of your transaction:

  1. Sign in to your Google Payments account at https://payments.google.com.

  2. On the left menu, select the “Subscriptions and services” page.

  3. On the “Other purchase activity” card, click View purchases.

  4. Click the “Google Play” registration transaction to see your payment method.

  5. You can click “Payment methods” on the left menu if you need to edit the addresses on your Google Payments account.

To add a new credit or debit card to your account, you can follow the instructions on the Google Payments Help Center (https://support.google.com/payments/answer/6220309).

How do I vertically center an H1 in a div?

HTML

<div id='sample'>
<span class='vertical'>Test Message</span>
</div>

CSS

    #sample 
    {
        height:100px;
         width:100%;
        background-color:#003366;
        display:table;
        text-align: center;

    }
    .vertical 
    {
           color:white;
         display:table-cell;
        vertical-align:middle;
}

Fiddle : Demo

Check if String / Record exists in DataTable

Use the Find method if item_manuf_id is a primary key:

var result = dtPs.Rows.Find("some value");

If you only want to know if the value is in there then use the Contains method.

if (dtPs.Rows.Contains("some value"))
{
  ...
}

Primary key restriction applies to Contains aswell.

Obtain form input fields using jQuery?

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

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

How to add a line break within echo in PHP?

You have to use br when using echo , like this :

echo "Thanks for your email" ."<br>". "Your orders details are below:"

and it will work properly

Set background image on grid in WPF using C#

I have my images in a separate class library ("MyClassLibrary") and they are placed in the folder "Images". In the example I used "myImage.jpg" as the background image.

  ImageBrush myBrush = new ImageBrush();
  Image image = new Image();
  image.Source = new BitmapImage(
      new Uri(
         "pack://application:,,,/MyClassLibrary;component/Images/myImage.jpg"));
  myBrush.ImageSource = image.Source;
  Grid grid = new Grid();
  grid.Background = myBrush;          

How can I install MacVim on OS X?

  1. Download the latest build from https://github.com/macvim-dev/macvim/releases

  2. Expand the archive.

  3. Put MacVim.app into /Applications/.

Done.

SSL Proxy/Charles and Android trouble

Edit - this answer was for an earlier version of Charles. See @semicircle21 answer below for the proper steps for v3.10.x -- much easier than this approach too... :-)

For what it's worth here are the step by step instructions for this. They should apply equally well in iOS too:

  1. Open Charles
  2. Go to Proxy > Proxy Settings > SSL
  3. Check “Enable SSL Proxying”
  4. Select “Add location” and enter the host name and port (if needed)
  5. Click ok and make sure the option is checked
  6. Download the Charles cert from here: Charles cert >
  7. Send that file to yourself in an email.
  8. Open the email on your device and select the cert
  9. In “Name the certificate” enter whatever you want
  10. Click OK and you should get a message that the certificate was installed

You should then be able to see the SSL files in Charles. If you want to intercept and change the values you can use the "Map Local" tool which is really awesome:

  1. In Charles go to Tools > Map Local
  2. Select "Add entry"
  3. Enter the values for the file you want to replace
  4. In “Local path” select the file you want the app to load instead
  5. Click OK
  6. Make sure the entry is selected and click OK
  7. Run your app
  8. You should see in “Notes” that your file loads instead of the live one

What is the behavior difference between return-path, reply-to and from?

I had to add a Return-Path header in emails send by a Redmine instance. I agree with greatwolf only the sender can determine a correct (non default) Return-Path. The case is the following : E-mails are send with the default email address : [email protected] But we want that the real user initiating the action receives the bounce emails, because he will be the one knowing how to fix wrong recipients emails (and not the application adminstrators that have other cats to whip :-) ). We use this and it works perfectly well with exim on the application server and zimbra as the final company mail server.

Visual Studio can't 'see' my included header files

Here's how I solved this problem.

  • Go to Project --> Show All Files.

enter image description here

  • Right click all the files in Solutions Explorer and Click on Include in Project in all the files you want to include.

enter image description here

Done :)

Staging Deleted files

Use git rm foo to stage the file for deletion. (This will also delete the file from the file system, if it hadn't been previously deleted. It can, of course, be restored from git, since it was previously checked in.)

To stage the file for deletion without deleting it from the file system, use git rm --cached foo

Using sendmail from bash script for multiple recipients

Try doing this :

recipients="[email protected],[email protected],[email protected]"

And another approach, using shell here-doc :

/usr/sbin/sendmail "$recipients" <<EOF
subject:$subject
from:$from

Example Message
EOF

Be sure to separate the headers from the body with a blank line as per RFC 822.

Learning Regular Expressions

The most important part is the concepts. Once you understand how the building blocks work, differences in syntax amount to little more than mild dialects. A layer on top of your regular expression engine's syntax is the syntax of the programming language you're using. Languages such as Perl remove most of this complication, but you'll have to keep in mind other considerations if you're using regular expressions in a C program.

If you think of regular expressions as building blocks that you can mix and match as you please, it helps you learn how to write and debug your own patterns but also how to understand patterns written by others.

Start simple

Conceptually, the simplest regular expressions are literal characters. The pattern N matches the character 'N'.

Regular expressions next to each other match sequences. For example, the pattern Nick matches the sequence 'N' followed by 'i' followed by 'c' followed by 'k'.

If you've ever used grep on Unix—even if only to search for ordinary looking strings—you've already been using regular expressions! (The re in grep refers to regular expressions.)

Order from the menu

Adding just a little complexity, you can match either 'Nick' or 'nick' with the pattern [Nn]ick. The part in square brackets is a character class, which means it matches exactly one of the enclosed characters. You can also use ranges in character classes, so [a-c] matches either 'a' or 'b' or 'c'.

The pattern . is special: rather than matching a literal dot only, it matches any character. It's the same conceptually as the really big character class [-.?+%$A-Za-z0-9...].

Think of character classes as menus: pick just one.

Helpful shortcuts

Using . can save you lots of typing, and there are other shortcuts for common patterns. Say you want to match a digit: one way to write that is [0-9]. Digits are a frequent match target, so you could instead use the shortcut \d. Others are \s (whitespace) and \w (word characters: alphanumerics or underscore).

The uppercased variants are their complements, so \S matches any non-whitespace character, for example.

Once is not enough

From there, you can repeat parts of your pattern with quantifiers. For example, the pattern ab?c matches 'abc' or 'ac' because the ? quantifier makes the subpattern it modifies optional. Other quantifiers are

  • * (zero or more times)
  • + (one or more times)
  • {n} (exactly n times)
  • {n,} (at least n times)
  • {n,m} (at least n times but no more than m times)

Putting some of these blocks together, the pattern [Nn]*ick matches all of

  • ick
  • Nick
  • nick
  • Nnick
  • nNick
  • nnick
  • (and so on)

The first match demonstrates an important lesson: * always succeeds! Any pattern can match zero times.

A few other useful examples:

  • [0-9]+ (and its equivalent \d+) matches any non-negative integer
  • \d{4}-\d{2}-\d{2} matches dates formatted like 2019-01-01

Grouping

A quantifier modifies the pattern to its immediate left. You might expect 0abc+0 to match '0abc0', '0abcabc0', and so forth, but the pattern immediately to the left of the plus quantifier is c. This means 0abc+0 matches '0abc0', '0abcc0', '0abccc0', and so on.

To match one or more sequences of 'abc' with zeros on the ends, use 0(abc)+0. The parentheses denote a subpattern that can be quantified as a unit. It's also common for regular expression engines to save or "capture" the portion of the input text that matches a parenthesized group. Extracting bits this way is much more flexible and less error-prone than counting indices and substr.

Alternation

Earlier, we saw one way to match either 'Nick' or 'nick'. Another is with alternation as in Nick|nick. Remember that alternation includes everything to its left and everything to its right. Use grouping parentheses to limit the scope of |, e.g., (Nick|nick).

For another example, you could equivalently write [a-c] as a|b|c, but this is likely to be suboptimal because many implementations assume alternatives will have lengths greater than 1.

Escaping

Although some characters match themselves, others have special meanings. The pattern \d+ doesn't match backslash followed by lowercase D followed by a plus sign: to get that, we'd use \\d\+. A backslash removes the special meaning from the following character.

Greediness

Regular expression quantifiers are greedy. This means they match as much text as they possibly can while allowing the entire pattern to match successfully.

For example, say the input is

"Hello," she said, "How are you?"

You might expect ".+" to match only 'Hello,' and will then be surprised when you see that it matched from 'Hello' all the way through 'you?'.

To switch from greedy to what you might think of as cautious, add an extra ? to the quantifier. Now you understand how \((.+?)\), the example from your question works. It matches the sequence of a literal left-parenthesis, followed by one or more characters, and terminated by a right-parenthesis.

If your input is '(123) (456)', then the first capture will be '123'. Non-greedy quantifiers want to allow the rest of the pattern to start matching as soon as possible.

(As to your confusion, I don't know of any regular-expression dialect where ((.+?)) would do the same thing. I suspect something got lost in transmission somewhere along the way.)

Anchors

Use the special pattern ^ to match only at the beginning of your input and $ to match only at the end. Making "bookends" with your patterns where you say, "I know what's at the front and back, but give me everything between" is a useful technique.

Say you want to match comments of the form

-- This is a comment --

you'd write ^--\s+(.+)\s+--$.

Build your own

Regular expressions are recursive, so now that you understand these basic rules, you can combine them however you like.

Tools for writing and debugging regexes:

Books

Free resources

Footnote

†: The statement above that . matches any character is a simplification for pedagogical purposes that is not strictly true. Dot matches any character except newline, "\n", but in practice you rarely expect a pattern such as .+ to cross a newline boundary. Perl regexes have a /s switch and Java Pattern.DOTALL, for example, to make . match any character at all. For languages that don't have such a feature, you can use something like [\s\S] to match "any whitespace or any non-whitespace", in other words anything.

node: command not found

The problem is that your PATH does not include the location of the node executable.

You can likely run node as "/usr/local/bin/node".

You can add that location to your path by running the following command to add a single line to your bashrc file:

echo 'export PATH=$PATH:/usr/local/bin' >> $HOME/.bashrc

Best way to check for "empty or null value"

If there may be empty trailing spaces, probably there isn't better solution. COALESCE is just for problems like yours.

How to loop through each and every row, column and cells in a GridView and get its value

foreach (DataGridViewRow row in dataGridView1.Rows)
        {
            for (int i = 0; i < dataGridView1.Columns.Count; i++)
            {
                String header = dataGridView1.Columns[i].HeaderText;
                //String cellText = row.Cells[i].Text;
                DataGridViewColumn column = dataGridView1.Columns[i]; // column[1] selects the required column 
                column.AutoSizeMode = DataGridViewAutoSizeColumnMode.AllCells; // sets the AutoSizeMode of column defined in previous line
                int colWidth = column.Width; // store columns width after auto resize           
                colWidth += 50; // add 30 pixels to what 'colWidth' already is
                this.dataGridView1.Columns[i].Width = colWidth; // set the columns width to the value stored in 'colWidth'
            }
        }

H2 in-memory database. Table not found

I was trying to fetch table meta data, but had the following error:

Using:

String JDBC_URL = "jdbc:h2:mem:test;DB_CLOSE_DELAY=-1";

DatabaseMetaData metaData = connection.getMetaData();
...
metaData.getColumns(...);

returned an empty ResultSet.

But using the following URL instead it worked properly:

String JDBC_URL = "jdbc:h2:mem:test;DB_CLOSE_DELAY=-1;DATABASE_TO_UPPER=false";

There was a need to specify: DATABASE_TO_UPPER=false

Get the last day of the month in SQL

Based on the most voted answer at below link I came up with the following solution:

 declare  @mydate date= '2020-11-09';
  SELECT DATEADD(month, DATEDIFF(month, 0, @mydate)+1, -1) AS lastOfMonth

link: How can I select the first day of a month in SQL?

Reload the page after ajax success

You use the ajaxStop to execute code when the ajax are completed:

$(document).ajaxStop(function(){
  setTimeout("window.location = 'otherpage.html'",100);
});

Begin, Rescue and Ensure in Ruby?

FYI, even if an exception is re-raised in the rescue section, the ensure block will be executed before the code execution continues to the next exception handler. For instance:

begin
  raise "Error!!"
rescue
  puts "test1"
  raise # Reraise exception
ensure
  puts "Ensure block"
end

Passing Variable through JavaScript from one html page to another page

Without reading your code but just your scenario, I would solve by using localStorage. Here's an example, I'll use prompt() for short.

On page1:

window.onload = function() {
   var getInput = prompt("Hey type something here: ");
   localStorage.setItem("storageName",getInput);
}

On page2:

window.onload = alert(localStorage.getItem("storageName"));

You can also use cookies but localStorage allows much more spaces, and they aren't sent back to servers when you request pages.

How can I use jQuery to make an input readonly?

In JQuery 1.12.1, my application uses code:

$('"#raisepay_id"')[0].readOnly=true;

$('"#raisepay_id"')[0].readOnly=false;

and it works.

How to check if a specific key is present in a hash or not?

You can use hash.keys.include?(key)

irb(main):001:0> hash = {"pot" => 1, "tot" => 2, "not" => 3}
=> {"pot"=>1, "tot"=>2, "not"=>3}
irb(main):002:0> key = "not"
=> "not"
irb(main):003:0> hash.keys.include?(key)
=> true

Get Windows version in a batch file

The first line forces a WMI console installation if required on a new build. WMI always returns a consistent string of "Version=x.x.xxxx" so the token parsing is always the same for all Windows versions.

Parsing from the VER output has variable text preceding the version info, making token positions random. Delimiters are only the '=' and '.' characters.

The batch addition allows me to easily check versions as '510' (XP) up to '10000' for Win10. I don't use the Build value.

Setlocal EnableDelayedExpansion

wmic os get version /value 1>nul 2>nul

if %errorlevel% equ 0 (
   for /F "tokens=2,3,4 delims==." %%A In ('wmic os get version /value')  Do (
      (Set /A "_MAJ=%%A")
      (Set /A "_MIN=%%B")
      (Set /A "_BLD=%%C")
      )
    (Set /A "_OSVERSION=!_MAJ!*100")
    (Set /A "_OSVERSION+=!_MIN!*10")
    )

endlocal

Simple way to count character occurrences in a string

Something a bit more functional, without Regex:

public static int count(String s, char c) {
    return s.length()==0 ? 0 : (s.charAt(0)==c ? 1 : 0) + count(s.substring(1),c);
}

It's no tail recursive, for the sake of clarity.

Change one value based on another value in pandas

This question might still be visited often enough that it's worth offering an addendum to Mr Kassies' answer. The dict built-in class can be sub-classed so that a default is returned for 'missing' keys. This mechanism works well for pandas. But see below.

In this way it's possible to avoid key errors.

>>> import pandas as pd
>>> data = { 'ID': [ 101, 201, 301, 401 ] }
>>> df = pd.DataFrame(data)
>>> class SurnameMap(dict):
...     def __missing__(self, key):
...         return ''
...     
>>> surnamemap = SurnameMap()
>>> surnamemap[101] = 'Mohanty'
>>> surnamemap[301] = 'Drake'
>>> df['Surname'] = df['ID'].apply(lambda x: surnamemap[x])
>>> df
    ID  Surname
0  101  Mohanty
1  201         
2  301    Drake
3  401         

The same thing can be done more simply in the following way. The use of the 'default' argument for the get method of a dict object makes it unnecessary to subclass a dict.

>>> import pandas as pd
>>> data = { 'ID': [ 101, 201, 301, 401 ] }
>>> df = pd.DataFrame(data)
>>> surnamemap = {}
>>> surnamemap[101] = 'Mohanty'
>>> surnamemap[301] = 'Drake'
>>> df['Surname'] = df['ID'].apply(lambda x: surnamemap.get(x, ''))
>>> df
    ID  Surname
0  101  Mohanty
1  201         
2  301    Drake
3  401         

Prevent HTML5 video from being downloaded (right-click saved)?

We ended up using AWS CloudFront with expiring URLs. The video will load, but by the time the user right clicks and chooses Save As the video url they initially received has expired. Do a search for CloudFront Origin Access Identity.

Producing the video url requires a key pair which can be created in the AWS CLI. FYI this is not my code but it works great!

$resource = 'http://cdn.yourwebsite.com/videos/yourvideourl.mp4';
$timeout = 4;

//This comes from key pair you generated for cloudfront
$keyPairId = "AKAJSDHFKASWERASDF";

$expires = time() + $timeout; //Time out in seconds
$json = '{"Statement":[{"Resource":"'.$resource.'","Condition" {"DateLessThan":{"AWS:EpochTime":'.$expires.'}}}]}';     

//Read Cloudfront Private Key Pair
$fp=fopen("/absolute/path/to/your/cloudfront_privatekey.pem","r"); 
$priv_key=fread($fp,8192); 
fclose($fp); 

//Create the private key
$key = openssl_get_privatekey($priv_key);
if(!$key)
{
    echo "<p>Failed to load private key!</p>";
    return;
}

//Sign the policy with the private key
if(!openssl_sign($json, $signed_policy, $key, OPENSSL_ALGO_SHA1))
{
    echo '<p>Failed to sign policy: '.openssl_error_string().'</p>';
    return;
}

//Create url safe signed policy
$base64_signed_policy = base64_encode($signed_policy);
$signature = str_replace(array('+','=','/'), array('-','_','~'), $base64_signed_policy);

//Construct the URL
$url = $resource.'?Expires='.$expires.'&Signature='.$signature.'&Key-Pair-Id='.$keyPairId;

return '<div class="videowrapper" ><video autoplay controls style="width:100%!important;height:auto!important;"><source src="'.$url.'" type="video/mp4">Your browser does not support the video tag.</video></div>';

How to allocate aligned memory only using the standard library?

Here's an alternate approach to the 'round up' part. Not the most brilliantly coded solution but it gets the job done, and this type of syntax is a bit easier to remember (plus would work for alignment values that aren't a power of 2). The uintptr_t cast was necessary to appease the compiler; pointer arithmetic isn't very fond of division or multiplication.

void *mem = malloc(1024 + 15);
void *ptr = (void*) ((uintptr_t) mem + 15) / 16 * 16;
memset_16aligned(ptr, 0, 1024);
free(mem);

MySQL error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near

How to find out what this MySQL Error is trying to say:

#1064 - You have an error in your SQL syntax;

This error has no clues in it. You have to double check all of these items to see where your mistake is:

  1. You have omitted, or included an unnecessary symbol: !@#$%^&*()-_=+[]{}\|;:'",<>/?
  2. A misplaced, missing or unnecessary keyword: select, into, or countless others.
  3. You have unicode characters that look like ascii characters in your query but are not recognized.
  4. Misplaced, missing or unnecessary whitespace or newlines between keywords.
  5. Unmatched single quotes, double quotes, parenthesis or braces.

Take away as much as you can from the broken query until it starts working. And then use PostgreSQL next time that has a sane syntax reporting system.

Access a JavaScript variable from PHP

try adding this to your js function:

    var outputvar = document.getElementById("your_div_id_inside_html_form");
    outputvar.innerHTML='<input id=id_to_send_to_php value='+your_js_var+'>';

Later in html:

    <div id="id_you_choosed_for_outputvar"></div>

this div will contain the js var to be passed through a form to another js function or to php, remember to place it inside your html form!. This solution is working fine for me.

In your specific geolocation case you can try adding the following to function showPosition(position):

    var outputlon = document.getElementById("lon1");
    outputlon.innerHTML = '<input id=lon value='+lon+'>';
    var outputlat = document.getElementById("lat1");
    outputlat.innerHTML = '<input id=lat value='+lat+'>';  

later add these div to your html form:

<div id=lat1></div>
<div id=lon1></div>

In these div you'll get latitude and longitude as input values for your php form, you would better hide them using css (show only the marker on a map if used) in order to avoid users to change them before to submit, and set your database to accept float values with lenght 10,7.

Hope this will help.

How to install Flask on Windows?

If You are using windows then go to python installation path like.

D:\Python37\Scripts>pip install Flask

it take some movement to download the package.

Draw radius around a point in Google map

In spherical geometry shapes are defined by points, lines and angles between those lines. You have only those rudimentary values to work with.

Therefore a circle (in terms of a a shape projected onto a sphere) is something that must be approximated using points. The more points, the more it'll look like a circle.

Having said that, realize that google maps is projecting the earth onto a flat surface (think "unrolling" the earth and stretching+flattening until it looks "square"). And if you have a flat coordinate system you can draw 2D objects on it all you want.

In other words you can draw a scaled vector circle on a google map. The catch is, google maps doesn't give it to you out of the box (they want to stay as close to GIS values as is pragmatically possible). They only give you GPolygon which they want you to use to approximate a circle. However, this guy did it using vml for IE and svg for other browsers (see "SCALED CIRCLES" section).

Now, going back to your question about Google Latitude using a scaled circle image (and this is probably the most useful to you): if you know the radius of your circle will never change (eg it's always 10 miles around some point), then the easiest solution would be to use a GGroundOverlay, which is just an image url + the GLatLngBounds the image represents. The only work you need to do then is cacluate the GLatLngBounds representing your 10 mile radius. Once you have that, the google maps api handles scaling your image as the user zooms in and out.

Developing for Android in Eclipse: R.java not regenerating

For me, I had linked v7 appcompat twice. Anyhow, in Eclipse, right click the project name in Package Explorer or Navigator, go to Properties, Android, and uncheck any duplicates in the Library section. You may need to Build --> Clean afterwards.

How do I change TextView Value inside Java Code?

First we need to find a Button:

Button mButton = (Button) findViewById(R.id.my_button);

After that, you must implement View.OnClickListener and there you should find the TextView and execute the method setText:

mButton.setOnClickListener(new View.OnClickListener {
    public void onClick(View v) {
        final TextView mTextView = (TextView) findViewById(R.id.my_text_view);
        mTextView.setText("Some Text");
    }
});

The remote certificate is invalid according to the validation procedure

.NET is seeing an invalid SSL certificate on the other end of the connection. There is a workaround for it, but obviously not recommended for production code:

// Put this somewhere that is only once - like an initialization method
ServicePointManager.ServerCertificateValidationCallback += new RemoteCertificateValidationCallback(ValidateCertificate);
...

static bool ValidateCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors errors)
{
   return true;
}

Force re-download of release dependency using Maven

Go to build path... delete existing maven library u added... click add library ... click maven managed dependencies... then click maven project settings... check resolve maven dependencies check box..it'll download all maven dependencies

pandas DataFrame: replace nan values with average of columns

using sklearn library preprocessing class

from sklearn.impute import SimpleImputer
missingvalues = SimpleImputer(missing_values = np.nan, strategy = 'mean', axis = 0)
missingvalues = missingvalues.fit(x[:,1:3])
x[:,1:3] = missingvalues.transform(x[:,1:3])

Note: In the recent version parameter missing_values value change to np.nan from NaN

How can I create directories recursively?

I agree with Cat Plus Plus's answer. However, if you know this will only be used on Unix-like OSes, you can use external calls to the shell commands mkdir, chmod, and chown. Make sure to pass extra flags to recursively affect directories:

>>> import subprocess
>>> subprocess.check_output(['mkdir', '-p', 'first/second/third']) 
# Equivalent to running 'mkdir -p first/second/third' in a shell (which creates
# parent directories if they do not yet exist).

>>> subprocess.check_output(['chown', '-R', 'dail:users', 'first'])
# Recursively change owner to 'dail' and group to 'users' for 'first' and all of
# its subdirectories.

>>> subprocess.check_output(['chmod', '-R', 'g+w', 'first'])
# Add group write permissions to 'first' and all of its subdirectories.

EDIT I originally used commands, which was a bad choice since it is deprecated and vulnerable to injection attacks. (For example, if a user gave input to create a directory called first/;rm -rf --no-preserve-root /;, one could potentially delete all directories).

EDIT 2 If you are using Python less than 2.7, use check_call instead of check_output. See the subprocess documentation for details.

How to round a number to significant figures in Python

This function does a normal round if the number is bigger than 10**(-decimal_positions), otherwise adds more decimal until the number of meaningful decimal positions is reached:

def smart_round(x, decimal_positions):
    dp = - int(math.log10(abs(x))) if x != 0.0 else int(0)
    return round(float(x), decimal_positions + dp if dp > 0 else decimal_positions)

Hope it helps.

Check if a variable is null in plsql

Use:

IF Var IS NULL THEN
  var := 5;
END IF;

Oracle 9i+:

var = COALESCE(Var, 5)

Other alternatives:

var = NVL(var, 5)

Reference:

Function overloading in Javascript - Best practices

INTRODUCTION

So far reading through so many answers would give anyone a headache. Anyone trying to know the concept would need to know the following prerequisites.

Function overloading Definition, Function Length property, Function argument property

Function overloading in its simplest form means that a function performs different tasks on the basis of number of arguments that are being passed to it. Notably the TASK1, TASK2 and TASK3 are highlighted below and are being performed on the basis of the number of arguments being passed to the same function fooYo.

// if we have a function defined below
function fooYo(){
     // do something here
}
// on invoking fooYo with different number of arguments it should be capable to do different things

fooYo();  // does TASK1
fooYo('sagar'); // does TASK2
fooYo('sagar','munjal'); // does TAKS3

NOTE - JS does not provide inbuilt ability of function overloading.

Alternative

John E Resig (creator of JS) has pointed out an alternative which uses the above prerequisites to achieve the ability to implement function overloading.

The code below uses a straightforward but naive approach by using if-else or switch statement.

  • evaluates the argument-length property.
  • different values result in invocation of different functions.

_x000D_
_x000D_
var ninja = {_x000D_
  whatever: function() {_x000D_
       switch (arguments.length) {_x000D_
         case 0:_x000D_
           /* do something */_x000D_
           break;_x000D_
         case 1:_x000D_
           /* do something else */_x000D_
           break;_x000D_
         case 2:_x000D_
           /* do yet something else */_x000D_
           break;_x000D_
       //and so on ..._x000D_
    } _x000D_
  }_x000D_
}
_x000D_
_x000D_
_x000D_

Another technique is much more clean and dynamic. The highlight of this technique is the addMethod generic function.

  • we define a function addMethod which is used to add different functions to an object with the same name but different functionalities.

  • below the addMethod function accepts three params object name object, function name name and the function that we want to be invoked fn.

  • Inside addMethod definition var old stores the reference to the previous function being stored by the help of closure - a protective bubble.

_x000D_
_x000D_
function addMethod(object, name, fn) {_x000D_
  var old = object[name];_x000D_
  object[name] = function(){_x000D_
    if (fn.length == arguments.length)_x000D_
      return fn.apply(this, arguments)_x000D_
    else if (typeof old == 'function')_x000D_
      return old.apply(this, arguments);_x000D_
  };_x000D_
};
_x000D_
_x000D_
_x000D_

  • use debugger to understand the code flow.
  • below the addMethod adds three functions which when invoked using ninja.whatever(x) with the number of arguments x which can be anything i.e. either blank or one or more than one invokes different functions as defined while making use of the addMethod function.

_x000D_
_x000D_
var ninja = {};_x000D_
debugger;_x000D_
_x000D_
_x000D_
addMethod(ninja,'whatever',function(){ console.log("I am the one with ZERO arguments supplied") });_x000D_
addMethod(ninja,'whatever',function(a){ console.log("I am the one with ONE arguments supplied") });_x000D_
addMethod(ninja,'whatever',function(a,b){ console.log("I am the one with TWO arguments supplied") });_x000D_
_x000D_
_x000D_
ninja.whatever();_x000D_
ninja.whatever(1,2);_x000D_
ninja.whatever(3);
_x000D_
_x000D_
_x000D_

Difference between javacore, thread dump and heap dump in Websphere

Heap dumps anytime you wish to see what is being held in memory Out-of-memory errors Heap dumps - picture of in memory objects - used for memory analysis Java cores - also known as thread dumps or java dumps, used for viewing the thread activity inside the JVM at a given time. IBM javacores should a lot of additional information besides just the threads and stacks -- used to determine hangs, deadlocks, and reasons for performance degredation System cores

How do you upload a file to a document library in sharepoint?

With SharePoint 2013 new library, I managed to do something like this:

private void UploadToSharePoint(string p, out string newUrl)  //p is path to file to load
{
    string siteUrl = "https://myCompany.sharepoint.com/site/";
    //Insert Credentials
    ClientContext context = new ClientContext(siteUrl);

    SecureString passWord = new SecureString();
    foreach (var c in "mypassword") passWord.AppendChar(c);
    context.Credentials = new SharePointOnlineCredentials("myUserName", passWord);
    Web site = context.Web;

    //Get the required RootFolder
    string barRootFolderRelativeUrl = "Shared Documents/foo/bar";
    Folder barFolder = site.GetFolderByServerRelativeUrl(barRootFolderRelativeUrl);

    //Create new subFolder to load files into
    string newFolderName = baseName + DateTime.Now.ToString("yyyyMMddHHmm");
    barFolder.Folders.Add(newFolderName);
    barFolder.Update();

    //Add file to new Folder
    Folder currentRunFolder = site.GetFolderByServerRelativeUrl(barRootFolderRelativeUrl + "/" + newFolderName);
    FileCreationInformation newFile = new FileCreationInformation { Content = System.IO.File.ReadAllBytes(@p), Url = Path.GetFileName(@p), Overwrite = true };
    currentRunFolder.Files.Add(newFile);
    currentRunFolder.Update();

    context.ExecuteQuery();

    //Return the URL of the new uploaded file
    newUrl = siteUrl + barRootFolderRelativeUrl + "/" + newFolderName + "/" + Path.GetFileName(@p);
}

java doesn't run if structure inside of onclick listener

both your conditions are the same:

if(s < f) {     calc = f - s;     n = s; }else if(f > s){     calc =  s - f;     n = f;  } 

so

if(s < f)   

and

}else if(f > s){ 

are the same

change to

}else if(f < s){ 

Turn a string into a valid filename?

Why not just wrap the "osopen" with a try/except and let the underlying OS sort out whether the file is valid?

This seems like much less work and is valid no matter which OS you use.

How to convert date format to milliseconds?

long millisecond = beginupd.getTime();

Date.getTime() JavaDoc states:

Returns the number of milliseconds since January 1, 1970, 00:00:00 GMT represented by this Date object.

How to reload .bash_profile from the command line?

I am running Sierra, and was working on this for a while (trying all recommended solutions). I became confounded so eventually tried restarting my computer! It worked

my conclusion is that sometimes a hard reset is necessary

Using partial views in ASP.net MVC 4

You're passing the same model to the partial view as is being passed to the main view, and they are different types. The model is a DbSet of Notes, where you need to pass in a single Note.

You can do this by adding a parameter, which I'm guessing as it's the create form would be a new Note

@Html.Partial("_CreateNote", new QuickNotes.Models.Note())