#Minimum spanning tree | Programs & Examples on Minimum spanning tree

When should I use Kruskal as opposed to Prim (and vice versa)?

I found a very nice thread on the net that explains the difference in a very straightforward way : http://www.thestudentroom.co.uk/showthread.php?t=232168.

Kruskal's algorithm will grow a solution from the cheapest edge by adding the next cheapest edge, provided that it doesn't create a cycle.

Prim's algorithm will grow a solution from a random vertex by adding the next cheapest vertex, the vertex that is not currently in the solution but connected to it by the cheapest edge.

Here attached is an interesting sheet on that topic. enter image description here

If you implement both Kruskal and Prim, in their optimal form : with a union find and a finbonacci heap respectively, then you will note how Kruskal is easy to implement compared to Prim.

Prim is harder with a fibonacci heap mainly because you have to maintain a book-keeping table to record the bi-directional link between graph nodes and heap nodes. With a Union Find, it's the opposite, the structure is simple and can even produce directly the mst at almost no additional cost.

Language Books/Tutorials for popular languages

Java

Java In a Nutshell.

The name is a bit of a misnomer because it's quite thick but it really has everything you need to learn Java.

Check for null variable in Windows batch

Late answer, but currently the accepted one is at least suboptimal.

Using quotes is ALWAYS better than using any other characters to enclose %1.
Because when %1 contains spaces or special characters like &, the IF [%1] == simply stops with a syntax error.

But for the case that %1 contains quotes, like in myBatch.bat "my file.txt", a simple IF "%1" == "" would fail.

But as you can't know if quotes are used or not, there is the syntax %~1, this removes enclosing quotes when necessary.

Therefore, the code should look like

set "file1=%~1"
IF "%~1"=="" set "file1=default file"

type "%file1%"   --- always enclose your variables in quotes

If you have to handle stranger and nastier arguments like myBatch.bat "This & will "^&crash
Then take a look at SO:How to receive even the strangest command line parameters?

How can I change the font-size of a select option?

try this

http://jsfiddle.net/VggvD/2/

CSS add your code

.select_join option{
    font-size:13px;
}

Getter and Setter?

You can use php magic methods __get and __set.

<?php
class MyClass {
  private $firstField;
  private $secondField;

  public function __get($property) {
    if (property_exists($this, $property)) {
      return $this->$property;
    }
  }

  public function __set($property, $value) {
    if (property_exists($this, $property)) {
      $this->$property = $value;
    }

    return $this;
  }
}
?>

Numpy: Creating a complex array from 2 real ones?

There's of course the rather obvious:

Data[...,0] + 1j * Data[...,1]

How do you specify the Java compiler version in a pom.xml file?

maven-compiler-plugin it's already present in plugins hierarchy dependency in pom.xml. Check in Effective POM.

For short you can use properties like this:

<properties>
   <maven.compiler.source>1.8</maven.compiler.source>
   <maven.compiler.target>1.8</maven.compiler.target>
</properties>

I'm using Maven 3.2.5.

How do I use FileSystemObject in VBA?

In excel 2013 the object creation string is:

Dim fso
Set fso = CreateObject("Scripting.FileSystemObject")

instead of the code in the answer above:

Dim fs,fname
Set fs=Server.CreateObject("Scripting.FileSystemObject")

How to display databases in Oracle 11g using SQL*Plus

Maybe you could use this view, but i'm not sure.

select * from v$database;

But I think It will only show you info about the current db.

Other option, if the db is running in linux... whould be something like this:

SQL>!grep SID $TNS_ADMIN/tnsnames.ora | grep -v PLSExtProc

HTML button onclick event

<body>
"button" value="Add Students" onclick="window.location.href='Students.html';"> 
<input type="button" value="Add Courses" onclick="window.location.href='Courses.html';"> 
<input type="button" value="Student Payments" onclick="window.location.href='Payments.html';">
</body>

Input type "number" won't resize

change type="number" to type="tel"

Decoding UTF-8 strings in Python

It's an encoding error - so if it's a unicode string, this ought to fix it:

text.encode("windows-1252").decode("utf-8")

If it's a plain string, you'll need an extra step:

text.decode("utf-8").encode("windows-1252").decode("utf-8")

Both of these will give you a unicode string.

By the way - to discover how a piece of text like this has been mangled due to encoding issues, you can use chardet:

>>> import chardet
>>> chardet.detect(u"And the Hipâ€™s coming, too")
{'confidence': 0.5, 'encoding': 'windows-1252'}

Sizing elements to percentage of screen width/height

You could build a Column/Row with Flexible or Expanded children that have flex values that add up to the percentages you want.

You may also find the AspectRatio widget useful.

In C#, how to check if a TCP port is available?

    public static bool TestOpenPort(int Port)
    {
        var tcpListener = default(TcpListener);

        try
        {
            var ipAddress = Dns.GetHostEntry("localhost").AddressList[0];

            tcpListener = new TcpListener(ipAddress, Port);
            tcpListener.Start();

            return true;
        }
        catch (SocketException)
        {
        }
        finally
        {
            if (tcpListener != null)
                tcpListener.Stop();
        }

        return false;
    }

Angular2 material dialog has issues - Did you add it to @NgModule.entryComponents?

In my case, I added my component to declarations and entryComponents and got the same errors. I also needed to add MatDialogModule to imports.

SQL query: Delete all records from the table except latest N?

This should work as well:

DELETE FROM [table] 
INNER JOIN (
    SELECT [id] 
    FROM (
        SELECT [id] 
        FROM [table] 
        ORDER BY [id] DESC
        LIMIT N
    ) AS Temp
) AS Temp2 ON [table].[id] = [Temp2].[id]

How to exclude *AutoConfiguration classes in Spring Boot JUnit tests?

I had a similar use case where I wanted to test a Spring Boot configured repository in isolation (in my case without Spring Security autoconfiguration which was failing my test). @SpringApplicationConfiguration uses SpringApplicationContextLoader and that has a JavaDoc stating

Can be used to test non-web features (like a repository layer) or start an fully-configured embedded servlet container.

However, like yourself, I could not work out how you are meant to configure the test to only test the repository layer using the main configuration entry point i.e. using your approach of @SpringApplicationConfiguration(classes = Application.class).

My solution was to create a completely new application context exclusive for testing. So in src/test/java I have two files in a sub-package called repo

RepoIntegrationTest.java
TestRepoConfig.java

where RepoIntegrationTest.java has

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = TestRepoConfig.class)
public class RepoIntegrationTest {

and TestRepoConfig.java has

@SpringBootApplication(exclude = SecurityAutoConfiguration.class)
public class TestRepoConfig {

It got me out of trouble but it would be really useful if anyone from the Spring Boot team could provide an alternative recommended solution

Stacked bar chart

You need to transform your data to long format and shouldn't use $ inside aes:

DF <- read.table(text="Rank F1     F2     F3
1    500    250    50
2    400    100    30
3    300    155    100
4    200    90     10", header=TRUE)

library(reshape2)
DF1 <- melt(DF, id.var="Rank")

library(ggplot2)
ggplot(DF1, aes(x = Rank, y = value, fill = variable)) + 
  geom_bar(stat = "identity")

enter image description here

How to import existing *.sql files in PostgreSQL 8.4?

Always preferred using a connection service file (lookup/google 'psql connection service file')

Then simply:

psql service={yourservicename} < {myfile.sql}

Where yourservicename is a section name from the service file.

UTF-8 in Windows 7 CMD

This question has been already answered in Unicode characters in Windows command line - how?

You missed one step -> you need to use Lucida console fonts in addition to executing chcp 65001 from cmd console.

Convert interface{} to int

maybe you need

func TransToString(data interface{}) (res string) {
    switch v := data.(type) {
    case float64:
        res = strconv.FormatFloat(data.(float64), 'f', 6, 64)
    case float32:
        res = strconv.FormatFloat(float64(data.(float32)), 'f', 6, 32)
    case int:
        res = strconv.FormatInt(int64(data.(int)), 10)
    case int64:
        res = strconv.FormatInt(data.(int64), 10)
    case uint:
        res = strconv.FormatUint(uint64(data.(uint)), 10)
    case uint64:
        res = strconv.FormatUint(data.(uint64), 10)
    case uint32:
        res = strconv.FormatUint(uint64(data.(uint32)), 10)
    case json.Number:
        res = data.(json.Number).String()
    case string:
        res = data.(string)
    case []byte:
        res = string(v)
    default:
        res = ""
    }
    return
}

How do I make a fully statically linked .exe with Visual Studio Express 2005?

In regards Jared's response, having Windows 2000 or better will not necessarily fix the issue at hand. Rob's response does work, however it is possible that this fix introduces security issues, as Windows updates will not be able to patch applications built as such.

In another post, Nick Guerrera suggests packaging the Visual C++ Runtime Redistributable with your applications, which installs quickly, and is independent of Visual Studio.

How can I undo a mysql statement that I just executed?

If you define table type as InnoDB, you can use transactions. You will need set AUTOCOMMIT=0, and after you can issue COMMIT or ROLLBACK at the end of query or session to submit or cancel a transaction.

ROLLBACK -- will undo the changes that you have made

Node.js: Python not found exception due to node-sass and node-gyp

My machine is Windows 10, I've faced similar problems while tried to compile SASS using node-sass package. My node version is v10.16.3 and npm version is 6.9.0

The way that I resolved the problem:

At first delete package-lock.json file and node_modules/ folder.
Open Windows PowerShell as Administrator.
Run the command npm i -g node-sass.
After that, go to the project folder and run npm install
And finally, run the SASS compiling script, in my case, it is npm run build:css

And it works!!

How to list active / open connections in Oracle?

When I'd like to view incoming connections from our application servers to the database I use the following command:

SELECT username FROM v$session 
WHERE username IS NOT NULL 
ORDER BY username ASC;

Simple, but effective.

WHERE vs HAVING

All other answers on this question didn't hit upon the key point.

Assume we have a table:

CREATE TABLE `table` (
 `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
 `value` int(10) unsigned NOT NULL,
 PRIMARY KEY (`id`),
 KEY `value` (`value`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8

And have 10 rows with both id and value from 1 to 10:

INSERT INTO `table`(`id`, `value`) VALUES (1, 1),(2, 2),(3, 3),(4, 4),(5, 5),(6, 6),(7, 7),(8, 8),(9, 9),(10, 10);

Try the following 2 queries:

SELECT `value` v FROM `table` WHERE `value`>5; -- Get 5 rows
SELECT `value` v FROM `table` HAVING `value`>5; -- Get 5 rows

You will get exactly the same results, you can see the HAVING clause can work without GROUP BY clause.

Here's the difference:

SELECT `value` v FROM `table` WHERE `v`>5;

Error #1054 - Unknown column 'v' in 'where clause'

SELECT `value` v FROM `table` HAVING `v`>5; -- Get 5 rows

WHERE clause allows a condition to use any table column, but it cannot use aliases or aggregate functions. HAVING clause allows a condition to use a selected (!) column, alias or an aggregate function.

This is because WHERE clause filters data before select, but HAVING clause filters resulting data after select.

So put the conditions in WHERE clause will be more efficient if you have many many rows in a table.

Try EXPLAIN to see the key difference:

EXPLAIN SELECT `value` v FROM `table` WHERE `value`>5;
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+
| id | select_type | table | type  | possible_keys | key   | key_len | ref  | rows | Extra                    |
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+
|  1 | SIMPLE      | table | range | value         | value | 4       | NULL |    5 | Using where; Using index |
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+

EXPLAIN SELECT `value` v FROM `table` having `value`>5;
+----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+
| id | select_type | table | type  | possible_keys | key   | key_len | ref  | rows | Extra       |
+----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+
|  1 | SIMPLE      | table | index | NULL          | value | 4       | NULL |   10 | Using index |
+----+-------------+-------+-------+---------------+-------+---------+------+------+-------------+

You can see either WHERE or HAVING uses index, but the rows are different.

What data is stored in Ephemeral Storage of Amazon EC2 instance?

According to AWS documentation [https://aws.amazon.com/premiumsupport/knowledge-center/instance-store-vs-ebs/] instance store volumes is not persistent through instance stops, terminations, or hardware failures. Any AMI created from instance stored disk doesn't contain data present in instance store so all instances launched by this AMI will not have data stored in instance store. Instance store can be used as cache for applications running on instance, for all persistent data you should use EBS.

Tomcat: LifecycleException when deploying

Tomcat has different WAR deployment ways. Some work, some don't. Please try the following deployment methods :

Automatic: Copy-paste your WAR file into ${CATALINA_HOME}/webapps. A folder with the same name will appear if everything goes right.
Manager Application: Upload the WAR file
Manager Application: Locate the WAR file

In my case, using the Manager Application (local URL: http://localhost:8080/manager) worked. Whereas deploying using a copy-paste resulted in your error.

Filtering DataSet

No mention of Merge?

DataSet newdataset = new DataSet();

newdataset.Merge( olddataset.Tables[0].Select( filterstring, sortstring ));

String array initialization in Java

You mean like:

String names[] = {"Ankit","Bohra","Xyz"};

But you can only do this in the same statement when you declare it

php search array key and get value

The key is already the ... ehm ... key

echo $array[20120504];

If you are unsure, if the key exists, test for it

$key = 20120504;
$result = isset($array[$key]) ? $array[$key] : null;

Minor addition:

$result = @$array[$key] ?: null;

One may argue, that @ is bad, but keep it serious: This is more readable and straight forward, isn't?

Update: With PHP7 my previous example is possible without the error-silencer

$result = $array[$key] ?? null;

How is the AND/OR operator represented as in Regular Expressions?

Not an expert in regex, but you can do ^((part1|part2)|(part1, part2))$. In words: "part 1 or part2 or both"

Detect if a Form Control option button is selected in VBA

You should remove .Value from all option buttons because option buttons don't hold the resultant value, the option group control does. If you omit .Value then the default interface will report the option button status, as you are expecting. You should write all relevant code under commandbutton_click events because whenever the commandbutton is clicked the option button action will run.

If you want to run action code when the optionbutton is clicked then don't write an if loop for that.

EXAMPLE:

Sub CommandButton1_Click
    If OptionButton1 = true then
        (action code...)
    End if
End sub

Sub OptionButton1_Click   
    (action code...)
End sub

What is the difference between utf8mb4 and utf8 charsets in MySQL?

The utf8mb4 character set is useful because nowadays we need support for storing not only language characters but also symbols, newly introduced emojis, and so on.

A nice read on How to support full Unicode in MySQL databases by Mathias Bynens can also shed some light on this.

Remove file extension from a file name string

The Path.GetFileNameWithoutExtension method gives you the filename you pass as an argument without the extension, as should be obvious from the name.

JavaScript console.log causes error: "Synchronous XMLHttpRequest on the main thread is deprecated..."

I have been looking at the answers all impressive. I think He should provide the code that is giving him a problem. Given the example below, If you have a script to link to jquery in page.php then you get that notice.

$().ready(function () {
    $.ajax({url: "page.php",
        type: 'GET',
        success: function (result) {
        $("#page").html(result);
   }});
 });

AngularJS: ng-model not binding to ng-checked for checkboxes

Can Declare As the in ng-init also getting true

<!doctype html>
<html ng-app="plunker" >
  <head>
    <meta charset="utf-8">
    <title>AngularJS Plunker</title>
    <script>document.write('<base href="' + document.location + '" />');</script>
    <link rel="stylesheet" href="style.css">
    <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.0.6/angular.js"></script>
    <script src="app.js"></script>
  </head>
  <body ng-controller="MainCtrl" ng-init="testModel['item1']= true">
    <label><input type="checkbox" name="test" ng-model="testModel['item1']"  /> Testing</label><br />
    <label><input type="checkbox" name="test" ng-model="testModel['item2']" /> Testing 2</label><br />
    <label><input type="checkbox" name="test" ng-model="testModel['item3']" /> Testing 3</label><br />
    <input type="button" ng-click="submit()" value="Submit" />
  </body>
</html>

And You Can Select the First One and Object Also Shown here true,false,flase

Notepad++ Setting for Disabling Auto-open Previous Files

My problem was that Notepad++ was crashing on a file I had previously opened; I was unable to open the application at all. This blog post discusses how to delete the data from the "Sessions" file so that Notepad++ will open without having any prior files open:

From the blog post:

Method 1 - edit session.xml

Open file session.xml in C:\Users\Username\AppData\Roaming\Notepad++ or %APPDATA%\Notepad++

Delete its contents and save it

Run Notepad++ , session.xml will get new content automatically

Method 2 - add the -nosession parameter to Notepad++ shortcut

Create a desktop shortcut referring to your Notepad++ program, e.g. C:\Program Files\Notepad++\notepad++.exe

Right click on this shortcut

In the "Target" field add the -nosession parameter so the target field looks exaxtly like (apostrophes included too): "C:\Program Files\Notepad++\notepad++.exe" -nosession

Save and run Notepad++ from this shortcut icon with no recent files

Note: This is not a permanent setting, this simply deletes the prior session's information / opened files and starts over.

Alternatively, if you know the file which is causing notepad++ to hang, you can simply rename the file and open notepad++. This will solve the problem.

I hadn't seen this solution listed when I was googling my problem so I wanted to add it here!

What does "The code generator has deoptimised the styling of [some file] as it exceeds the max of "100KB"" mean?

I tried Ricardo Stuven's way but it didn't work for me. What worked in the end was adding "compact": false to my .babelrc file:

{
    "compact": false,
    "presets": ["latest", "react", "stage-0"]
}

Perl: function to trim string leading and trailing whitespace

According to this perlmonk's thread:

$string =~ s/^\s+|\s+$//g;

How to extract duration time from ffmpeg output?

I would just do this in C++ with a text file and extract the tokens. Why? I am not a linux terminal expert like the others.
To set it up I would do this in Linux..

ffmpeg -i 2>&1 | grep "" > mytext.txt

and then run some C++ app to get the data needed. Maybe extract all the important values and reformat it for further processing by using tokens. I will just have to work on my own solution and people will just make fun of me because I am a linux newbie and I do not like scripting too much.

How can I open Windows Explorer to a certain directory from within a WPF app?

You can use System.Diagnostics.Process.Start.

Or use the WinApi directly with something like the following, which will launch explorer.exe. You can use the fourth parameter to ShellExecute to give it a starting directory.

public partial class Window1 : Window
{
    public Window1()
    {
        ShellExecute(IntPtr.Zero, "open", "explorer.exe", "", "", ShowCommands.SW_NORMAL);
        InitializeComponent();
    }

    public enum ShowCommands : int
    {
        SW_HIDE = 0,
        SW_SHOWNORMAL = 1,
        SW_NORMAL = 1,
        SW_SHOWMINIMIZED = 2,
        SW_SHOWMAXIMIZED = 3,
        SW_MAXIMIZE = 3,
        SW_SHOWNOACTIVATE = 4,
        SW_SHOW = 5,
        SW_MINIMIZE = 6,
        SW_SHOWMINNOACTIVE = 7,
        SW_SHOWNA = 8,
        SW_RESTORE = 9,
        SW_SHOWDEFAULT = 10,
        SW_FORCEMINIMIZE = 11,
        SW_MAX = 11
    }

    [DllImport("shell32.dll")]
    static extern IntPtr ShellExecute(
        IntPtr hwnd,
        string lpOperation,
        string lpFile,
        string lpParameters,
        string lpDirectory,
        ShowCommands nShowCmd);
}

The declarations come from the pinvoke.net website.

Dark color scheme for Eclipse

I have to say, this is one area where Eclipse is really weak. Specifically, the import/export of preferences applies to ALL preferences. There is no way to import say just the fonts/color preferences (like you can with Visual Studio) without mucking up my key binding preferences.

Also, I have tried several of these preference files referenced above, and they completely break my Eclipse install.

How to retrieve the current version of a MySQL database management system (DBMS)?

SHOW VARIABLES LIKE "%version%";
+-------------------------+------------------------------------------+
| Variable_name           | Value                                    |
+-------------------------+------------------------------------------+
| protocol_version        | 10                                       |
| version                 | 5.0.27-standard                          |
| version_comment         | MySQL Community Edition - Standard (GPL) |
| version_compile_machine | i686                                     |
| version_compile_os      | pc-linux-gnu                             |
+-------------------------+------------------------------------------+
5 rows in set (0.04 sec)

MySQL 5.0 Reference Manual (pdf) - Determining Your Current MySQL Version - page 42

JavaScript get element by name

document.getElementsByName("myInput")[0].value;

state provider and route provider in angularJS

You shouldn't use both ngRoute and UI-router. Here's a sample code for UI-router:

_x000D_

repoApp.config(function($stateProvider, $urlRouterProvider) {_x000D_
  _x000D_
  $stateProvider_x000D_
    .state('state1', {_x000D_
      url: "/state1",_x000D_
      templateUrl: "partials/state1.html",_x000D_
      controller: 'YourCtrl'_x000D_
    })_x000D_
    _x000D_
    .state('state2', {_x000D_
      url: "/state2",_x000D_
      templateUrl: "partials/state2.html",_x000D_
      controller: 'YourOtherCtrl'_x000D_
    });_x000D_
    $urlRouterProvider.otherwise("/state1");_x000D_
});_x000D_
//etc.

_x000D_

You can find a great answer on the difference between these two in this thread: What is the difference between angular-route and angular-ui-router?

You can also consult UI-Router's docs here: https://github.com/angular-ui/ui-router

Select random element in a list of R?

What does the 'export' command do?

export in sh and related shells (such as bash), marks an environment variable to be exported to child-processes, so that the child inherits them.

export is defined in POSIX:

The shell shall give the export attribute to the variables corresponding to the specified names, which shall cause them to be in the environment of subsequently executed commands. If the name of a variable is followed by = word, then the value of that variable shall be set to word.

Is there a simple way to remove multiple spaces in a string?

To remove white space, considering leading, trailing and extra white space in between words, use:

(?<=\s) +|^ +(?=\s)| (?= +[\n\0])

The first or deals with leading white space, the second or deals with start of string leading white space, and the last one deals with trailing white space.

For proof of use, this link will provide you with a test.

https://regex101.com/r/meBYli/4

This is to be used with the re.split function.

What are major differences between C# and Java?

Generics:

With Java generics, you don't actually get any of the execution efficiency that you get with .NET because when you compile a generic class in Java, the compiler takes away the type parameter and substitutes Object everywhere. For instance if you have a Foo<T> class the java compiler generates Byte Code as if it was Foo<Object>. This means casting and also boxing/unboxing will have to be done in the "background".

I've been playing with Java/C# for a while now and, in my opinion, the major difference at the language level are, as you pointed, delegates.

XPath to return only elements containing the text, and not its parents

Try

//re:*[. ='match']

How can I detect window size with jQuery?

You could also use plain Javascript window.innerWidth to compare width.

But use jQuery's .resize() fired automatically for you:

$( window ).resize(function() {
  // your code...
});

http://api.jquery.com/resize/

Bootstrap 3.0 Popovers and tooltips

You have a syntax error in your script and, as noted by xXPhenom22Xx, you must instantiate the tooltip.

<script type="text/javascript">

    $(document).ready(function() {

        $('.btn-danger').tooltip();

    }); //END $(document).ready()

</script>

Note that I used your class "btn-danger". You can create a different class, or use an id="someidthatimakeup".

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

Make sure you import MaterialModule as well since you are using md-input which does not belong to FormsModule

Differences between TCP sockets and web sockets, one more time

WebSocket is basically an application protocol (with reference to the ISO/OSI network stack), message-oriented, which makes use of TCP as transport layer.

The idea behind the WebSocket protocol consists of reusing the established TCP connection between a Client and Server. After the HTTP handshake the Client and Server start speaking WebSocket protocol by exchanging WebSocket envelopes. HTTP handshaking is used to overcome any barrier (e.g. firewalls) between a Client and a Server offering some services (usually port 80 is accessible from anywhere, by anyone). Client and Server can switch over speaking HTTP in any moment, making use of the same TCP connection (which is never released).

Behind the scenes WebSocket rebuilds the TCP frames in consistent envelopes/messages. The full-duplex channel is used by the Server to push updates towards the Client in an asynchronous way: the channel is open and the Client can call any futures/callbacks/promises to manage any asynchronous WebSocket received message.

To put it simply, WebSocket is a high level protocol (like HTTP itself) built on TCP (reliable transport layer, on per frame basis) that makes possible to build effective real-time application with JS Clients (previously Comet and long-polling techniques were used to pull updates from the Server before WebSockets were implemented. See Stackoverflow post: Differences between websockets and long polling for turn based game server ).

How to Parse a JSON Object In Android

Take a look at http://developer.android.com/reference/org/json/JSONTokener.html

This might fix your issue.

Does Notepad++ show all hidden characters?

For non-printing characters, you can do the following:

if you could identify the character, where cursor takes 2 arrow keys to move, just select that character.
do Ctrl-F
now you can count or replace or even mark all such characters

Is it safe to store a JWT in localStorage with ReactJS?

Basically it's OK to store your JWT in your localStorage.

And I think this is a good way. If we are talking about XSS, XSS using CDN, it's also a potential risk of getting your client's login/pass as well. Storing data in local storage will prevent CSRF attacks at least.

You need to be aware of both and choose what you want. Both attacks it's not all you are need to be aware of, just remember: YOUR ENTIRE APP IS ONLY AS SECURE AS THE LEAST SECURE POINT OF YOUR APP.

Once again storing is OK, be vulnerable to XSS, CSRF,... isn't

Use a JSON array with objects with javascript

By 'JSON array containing objects' I guess you mean a string containing JSON?

If so you can use the safe var myArray = JSON.parse(myJSON) method (either native or included using JSON2), or the usafe var myArray = eval("(" + myJSON + ")"). eval should normally be avoided, but if you are certain that the content is safe, then there is no problem.

After that you just iterate over the array as normal.

for (var i = 0; i < myArray.length; i++) {
    alert(myArray[i].Title);
}

Error:Conflict with dependency 'com.google.code.findbugs:jsr305'

The reason why this happen is that diff dependency use same lib of diff version.
So, there are 3 steps or (1 step) to solve this problem.

1st

Add

configurations.all {
    resolutionStrategy.force 'com.google.code.findbugs:jsr305:2.0.1'
}

to your build.gradle file in android {...}

2nd

Open terminal in android studio
run ./gradlew -q app:dependencies command.

3rd

Click Clean Project from menu bar of android studio in Build list.
It will rebuild the project, and then remove code in 1st step.

Maybe you need just exec 2nd step. I can't rollback when error occurs. Have a try.

How to reload/refresh an element(image) in jQuery

with one line with no worries about hardcoding the image src into the javascript (thanks to jeerose for the ideas:

$("#myimg").attr("src", $("#myimg").attr("src")+"?timestamp=" + new Date().getTime());

How to solve a timeout error in Laravel 5

Sometimes you just need to optimize your code or query, Setting more max_execution_time is not a solution.

It is not suggested to take more than 30 for loading a webpage if a task takes more time need to be a queue.

How do I render a shadow?

    viewStyle : {
    backgroundColor: '#F8F8F8',
    justifyContent: 'center',
    alignItems: 'center',
    height: 60,
    paddingTop: 15,
    shadowColor: '#000',
    shadowOffset: { width: 0, height: 2 },
    shadowOpacity: 0.2,
    marginBottom: 10,
    elevation: 2,
    position: 'relative'
},

Use marginBottom: 10

How to fill a Javascript object literal with many static key/value pairs efficiently?

In ES2015 a.k.a ES6 version of JavaScript, a new datatype called Map is introduced.

let map = new Map([["key1", "value1"], ["key2", "value2"]]);
map.get("key1"); // => value1

check this reference for more info.

iOS9 getting error “an SSL error has occurred and a secure connection to the server cannot be made”

If you are just targeting specific domains you can try and add this in your application's Info.plist:

<key>NSAppTransportSecurity</key>
<dict>
    <key>NSExceptionDomains</key>
    <dict>
        <key>example.com</key>
        <dict>
            <key>NSExceptionRequiresForwardSecrecy</key>
            <false/>
            <key>NSIncludesSubdomains</key>
            <true/>
        </dict>
    </dict>
</dict>

How to create enum like type in TypeScript?

This is now part of the language. See TypeScriptLang.org > Basic Types > enum for the documentation on this. An excerpt from the documentation on how to use these enums:

enum Color {Red, Green, Blue};
var c: Color = Color.Green;

Or with manual backing numbers:

enum Color {Red = 1, Green = 2, Blue = 4};
var c: Color = Color.Green;

You can also go back to the enum name by using for example Color[2].

Here's an example of how this all goes together:

module myModule {
    export enum Color {Red, Green, Blue};

    export class MyClass {
        myColor: Color;

        constructor() {
            console.log(this.myColor);
            this.myColor = Color.Blue;
            console.log(this.myColor);
            console.log(Color[this.myColor]);
        }
    }
}

var foo = new myModule.MyClass();

This will log:

undefined  
2  
Blue

Because, at the time of writing this, the Typescript Playground will generate this code:

var myModule;
(function (myModule) {
    (function (Color) {
        Color[Color["Red"] = 0] = "Red";
        Color[Color["Green"] = 1] = "Green";
        Color[Color["Blue"] = 2] = "Blue";
    })(myModule.Color || (myModule.Color = {}));
    var Color = myModule.Color;
    ;
    var MyClass = (function () {
        function MyClass() {
            console.log(this.myColor);
            this.myColor = Color.Blue;
            console.log(this.myColor);
            console.log(Color[this.myColor]);
        }
        return MyClass;
    })();
    myModule.MyClass = MyClass;
})(myModule || (myModule = {}));
var foo = new myModule.MyClass();

How do I import a .dmp file into Oracle?

i got solution what you are getting as per imp help=y it is mentioned that imp is only valid for TRANSPORT_TABLESPACE as below:

Keyword  Description (Default)       Keyword      Description (Default)
--------------------------------------------------------------------------
USERID   username/password           FULL         import entire file (N)
BUFFER   size of data buffer         FROMUSER     list of owner usernames
FILE     input files (EXPDAT.DMP)    TOUSER       list of usernames
SHOW     just list file contents (N) TABLES       list of table names
IGNORE   ignore create errors (N)    RECORDLENGTH length of IO record
GRANTS   import grants (Y)           INCTYPE      incremental import type
INDEXES  import indexes (Y)          COMMIT       commit array insert (N)
ROWS     import data rows (Y)        PARFILE      parameter filename
LOG      log file of screen output   CONSTRAINTS  import constraints (Y)
DESTROY                overwrite tablespace data file (N)
INDEXFILE              write table/index info to specified file
SKIP_UNUSABLE_INDEXES  skip maintenance of unusable indexes (N)
FEEDBACK               display progress every x rows(0)
TOID_NOVALIDATE        skip validation of specified type ids
FILESIZE               maximum size of each dump file
STATISTICS             import precomputed statistics (always)
RESUMABLE              suspend when a space related error is encountered(N)
RESUMABLE_NAME         text string used to identify resumable statement
RESUMABLE_TIMEOUT      wait time for RESUMABLE
COMPILE                compile procedures, packages, and functions (Y)
STREAMS_CONFIGURATION  import streams general metadata (Y)
STREAMS_INSTANTIATION  import streams instantiation metadata (N)
DATA_ONLY              import only data (N)

The following keywords only apply to transportable tablespaces
TRANSPORT_TABLESPACE import transportable tablespace metadata (N)
TABLESPACES tablespaces to be transported into database
DATAFILES datafiles to be transported into database
TTS_OWNERS users that own data in the transportable tablespace set

So, Please create table space for your user:

CREATE TABLESPACE <tablespace name> DATAFILE <path to save, example: 'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\ABC.dbf'> SIZE 100M AUTOEXTEND ON NEXT 100M MAXSIZE 10G EXTENT MANAGEMENT LOCAL UNIFORM SIZE 1M;

How to get a substring of text?

If you want a string, then the other answers are fine, but if what you're looking for is the first few letters as characters you can access them as a list:

your_text.chars.take(30)

Error: Node Sass version 5.0.0 is incompatible with ^4.0.0

If the error is

Error: Node Sass version 5.0.0 is incompatible with ^4.0.0

Step1: stop the server

Step2: run commands are npm uninstall node-sass

Step3: check node-sass in package.json if node-sass is available in the file then again run Step2.

Step4: npm install [email protected] <=== run command

Step5: wait until the command successfully runs.

Step6: start-server using npm start

PostgreSQL psql terminal command

psql --pset=format=FORMAT

Great for executing queries from command line, e.g.

psql --pset=format=unaligned -c "select bandanavalue from bandana where bandanakey = 'atlassian.confluence.settings';"

Using jquery to delete all elements with a given id

if you want to remove all elements with matching ID parts, for example:

<span id='myID_123'>
<span id='myID_456'>
<span id='myID_789'>

try this:

$("span[id*=myID]").remove();

don't forget the '*' - this will remove them all at once - cheers

Working Demo

SQLite Query in Android to count rows

See rawQuery(String, String[]) and the documentation for Cursor

Your DADABASE_COMPARE SQL statement is currently invalid, loginname and loginpass won't be escaped, there is no space between loginname and the and, and you end the statement with ); instead of ; -- If you were logging in as bob with the password of password, that statement would end up as

select count(*) from users where uname=boband pwd=password);

Also, you should probably use the selectionArgs feature, instead of concatenating loginname and loginpass.

To use selectionArgs you would do something like

final String SQL_STATEMENT = "SELECT COUNT(*) FROM users WHERE uname=? AND pwd=?";

private void someMethod() {
    Cursor c = db.rawQuery(SQL_STATEMENT, new String[] { loginname, loginpass });
    ...
}

Regex empty string or email

If you are using it within rails - activerecord validation you can set allow_blank: true

As:

validates :email, allow_blank: true, format: { with: EMAIL_REGEX }

Passing additional variables from command line to make

Say you have a makefile like this:

action:
    echo argument is $(argument)

You would then call it make action argument=something

Autocompletion of @author in Intellij

You can work around that via a Live Template. Go to Settings -> Live Template, click the "Add"-Button (green plus on the right).

In the "Abbreviation" field, enter the string that should activate the template (e.g. @a), and in the "Template Text" area enter the string to complete (e.g. @author - My Name). Set the "Applicable context" to Java (Comments only maybe) and set a key to complete (on the right).

I tested it and it works fine, however IntelliJ seems to prefer the inbuild templates, so "@a + Tab" only completes "author". Setting the completion key to Space worked however.

To change the user name that is automatically inserted via the File Templates (when creating a class for example), can be changed by adding

-Duser.name=Your name

to the idea.exe.vmoptions or idea64.exe.vmoptions (depending on your version) in the IntelliJ/bin directory.

Restart IntelliJ

Merge some list items in a Python List

just a variation

alist=["a", "b", "c", "d", "e", 0, "g"]
alist[3:6] = [''.join(map(str,alist[3:6]))]
print alist

Difference between the 'controller', 'link' and 'compile' functions when defining a directive

running code before Compilation : use controller
running code after Compilation : use Link

Angular convention : write business logic in controller and DOM manipulation in link.

Apart from this you can call one controller function from link function of another directive.For example you have 3 custom directives

<animal>
<panther>
<leopard></leopard>
</panther> 
</animal>

and you want to access animal from inside of "leopard" directive.

http://egghead.io/lessons/angularjs-directive-communication will be helpful to know about inter-directive communication

How can I disable notices and warnings in PHP within the .htaccess file?

Try:

php_value error_reporting 2039

Stylesheet not loaded because of MIME-type

In my case I had to both make sure that the link was relative and the rel property was after the href property:

<link href="/assets/styles/iframe.css" rel="stylesheet">

scrollbars in JTextArea

Simple Way to add JTextArea in JScrollBar with JScrollPan

import javax.swing.*;
public class ScrollingTextArea 
{
     JFrame f;
     JTextArea ta;
     JScrollPane scrolltxt;

     public ScrollingTextArea() 
     {
        // TODO Auto-generated constructor stub

        f=new JFrame();
        f.setLayout(null);
        f.setVisible(true);
        f.setSize(500,500);
        ta=new JTextArea();
        ta.setBounds(5,5,100,200);

        scrolltxt=new JScrollPane(ta);
        scrolltxt.setBounds(3,3,400,400);

         f.add(scrolltxt);

     }

     public static void main(String[] args) 
     {
        new ScrollingTextArea();
     }
}

What is the difference between DBMS and RDBMS?

Every RDBMS is a DBMS, but the opposite is not true: RDBMS is a DBMS which is based on the relational model, but not every DBMS must be relational.

However, since RDBMS are most common, sometimes the term DBMS is used to denote a DBMS which is NOT relational. It depends on the context.

Environ Function code samples for VBA

Some time when we use Environ() function we may get the Library or property not found error. Use VBA.Environ() or VBA.Environ$() to avoid the error.

visual c++: #include files from other projects in the same solution

Settings for compiler

In the project where you want to #include the header file from another project, you will need to add the path of the header file into the Additional Include Directories section in the project configuration.

To access the project configuration:

Right-click on the project, and select Properties.
Select Configuration Properties->C/C++->General.
Set the path under Additional Include Directories.

How to include

To include the header file, simply write the following in your code:

#include "filename.h"

Note that you don't need to specify the path here, because you include the directory in the Additional Include Directories already, so Visual Studio will know where to look for it.

If you don't want to add every header file location in the project settings, you could just include a directory up to a point, and then #include relative to that point:

// In project settings
Additional Include Directories    ..\..\libroot

// In code
#include "lib1/lib1.h"    // path is relative to libroot
#include "lib2/lib2.h"    // path is relative to libroot

Setting for linker

If using static libraries (i.e. .lib file), you will also need to add the library to the linker input, so that at linkage time the symbols can be linked against (otherwise you'll get an unresolved symbol):

Right-click on the project, and select Properties.
Select Configuration Properties->Linker->Input
Enter the library under Additional Dependencies.

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

I don't know a good free tool but winmerge is ok(ish). I've been using the beyond compare tools since 1999 and can't rate it enough - it costs about 50 USD and this investment has paid for it self in time savings more than I can possible imagine.

Sometimes tools should be paid for if they are very very good.

Compilation error - missing zlib.h

I also had the same problem. Then I installed the zlib, still the problem remained the same. Then I added the following lines in my .bashrc and it worked. You should replace the path with your zlib installation path. (I didn't have root privileges).

export PATH =$PATH:$HOME/Softwares/library/Zlib/zlib-1.2.11/
export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:$HOME/Softwares/library/Zlib/zlib-1.2.11/lib/
export LIBRARY_PATH=$LIBRARY_PATH:$HOME/Softwares/library/Zlib/zlib-1.2.11/lib/
export C_INCLUDE_PATH=$HOME/Softwares/library/Zlib/zlib-1.2.11/include/
export CPLUS_INCLUDE_PATH=$HOME/Softwares/library/Zlib/zlib-1.2.11/include/
export PKG_CONFIG_PATH=$HOME/Softwares/library/Zlib/zlib-1.2.11/lib/pkgconfig

Cross-browser bookmark/add to favorites JavaScript

I'm thinking no. Bookmarks/favorites should be under the control of the user, imagine if any site you visited could insert itself into your bookmarks with just some javascript.

How do I change the ID of a HTML element with JavaScript?

That seems to work for me:

<html>
<head><style>
#monkey {color:blue}
#ape {color:purple}
</style></head>
<body>
<span id="monkey" onclick="changeid()">
fruit
</span>
<script>
function changeid ()
{
var e = document.getElementById("monkey");
e.id = "ape";
}
</script>
</body>
</html>

The expected behaviour is to change the colour of the word "fruit".

Perhaps your document was not fully loaded when you called the routine?

Reading my own Jar's Manifest

A simpler way to do this is to use getPackage(). For example, to get Implementation-Version:

Application.class.getPackage().getImplementationVersion()

Mockito. Verify method arguments

You can also use TypeSafeDiagnosingMatcher

    private Matcher<GetPackagesRequest> expectedPackageRequest(final AvailabilityRequest request) {
    return new TypeSafeDiagnosingMatcher<GetPackagesRequest>() {

        StringBuilder text = new StringBuilder(500);

        @Override
        protected boolean matchesSafely(GetPackagesRequest req, Description desc) {
            String productCode = req.getPackageIds().iterator().next().getValue();
            if (productCode.equals(request.getSupplierProductCode())) {
                text.append("ProductCode not equal! " + productCode + " , " + request.getSupplierProductCode());
                return true;
            }

            text.append(req.toString());
            return false;
        }

        @Override
        public void describeTo(Description d) {
            d.appendText(text.toString());
        }
    };
}

Then verify that invocation:

Mockito.verify(client).getPackages(Mockito.argThat(expectedPackageRequest(request)));

How to calculate the inverse of the normal cumulative distribution function in python?

Starting Python 3.8, the standard library provides the NormalDist object as part of the statistics module.

It can be used to get the inverse cumulative distribution function (inv_cdf - inverse of the cdf), also known as the quantile function or the percent-point function for a given mean (mu) and standard deviation (sigma):

from statistics import NormalDist

NormalDist(mu=10, sigma=2).inv_cdf(0.95)
# 13.289707253902943

Which can be simplified for the standard normal distribution (mu = 0 and sigma = 1):

NormalDist().inv_cdf(0.95)
# 1.6448536269514715

How to get all elements by class name?

What is the difference between String.slice and String.substring?

The only difference between slice and substring method is of arguments

Both take two arguments e.g. start/from and end/to.

You cannot pass a negative value as first argument for substring method but for slice method to traverse it from end.

Slice method argument details:

REF: http://www.thesstech.com/javascript/string_slice_method

Arguments

start_index Index from where slice should begin. If value is provided in negative it means start from last. e.g. -1 for last character. end_index Index after end of slice. If not provided slice will be taken from start_index to end of string. In case of negative value index will be measured from end of string.

Substring method argument details:

REF: http://www.thesstech.com/javascript/string_substring_method

Arguments

from It should be a non negative integer to specify index from where sub-string should start. to An optional non negative integer to provide index before which sub-string should be finished.

Get top first record from duplicate records having no unique identity

SELECT TOP 1000 MAX(tel) FROM TableName WHERE Id IN 
(
SELECT Id FROM TableName
GROUP BY Id
HAVING COUNT(*) > 1
) 
GROUP BY Id

The database cannot be opened because it is version 782. This server supports version 706 and earlier. A downgrade path is not supported

This solution solve my problem: (from: https://msdn.microsoft.com/en-us/library/ms239722.aspx)

To permanently attach a database file (.mdf) from the Data Connections node

Open the shortcut menu for Data Connections and choose Add New Connection.

The Add Connection dialog box appears.
Choose the Change button.

The Change Data Source dialog box appears.
Select Microsoft SQL Server and choose the OK button.

The Add Connection dialog box reappears, with Microsoft SQL Server (SqlClient) displayed in the Data source text box.
In the Server Name box, type or browse to the path to the local instance of SQL Server. You can type the following:
- "." for the default instance on your computer.
- "(LocalDB)\v11.0" for the default instance of SQL Server Express LocalDB.
- ".\SQLEXPRESS" for the default instance of SQL Server Express.
For information about SQL Server Express LocalDB and SQL Server Express, see Local Data Overview.
Select either Use Windows Authentication or Use SQL Server Authentication.
Choose Attach a database file, Browse, and open an existing .mdf file.
Choose the OK button.

The new database appears in Server Explorer. It will remain connected to SQL Server until you explicitly detach it.

Regular expression for decimal number

^[0-9]([.,][0-9]{1,3})?$

It allows:

BUT NOT:

.1
,1
12.1
12,1
1.
1,
1.2345
1,2345

AngularJS: How can I pass variables between controllers?

The following example shows how to pass variables between siblings controllers and take an action when the value changes.

Use case example: you have a filter in a sidebar that changes the content of another view.

_x000D_

angular.module('myApp', [])_x000D_
_x000D_
  .factory('MyService', function() {_x000D_
_x000D_
    // private_x000D_
    var value = 0;_x000D_
_x000D_
    // public_x000D_
    return {_x000D_
      _x000D_
      getValue: function() {_x000D_
        return value;_x000D_
      },_x000D_
      _x000D_
      setValue: function(val) {_x000D_
        value = val;_x000D_
      }_x000D_
      _x000D_
    };_x000D_
  })_x000D_
  _x000D_
  .controller('Ctrl1', function($scope, $rootScope, MyService) {_x000D_
_x000D_
    $scope.update = function() {_x000D_
      MyService.setValue($scope.value);_x000D_
      $rootScope.$broadcast('increment-value-event');_x000D_
    };_x000D_
  })_x000D_
  _x000D_
  .controller('Ctrl2', function($scope, MyService) {_x000D_
_x000D_
    $scope.value = MyService.getValue();_x000D_
_x000D_
    $scope.$on('increment-value-event', function() {    _x000D_
      $scope.value = MyService.getValue();_x000D_
    });_x000D_
  });

_x000D_

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script>_x000D_
_x000D_
<div ng-app="myApp">_x000D_
  _x000D_
  <h3>Controller 1 Scope</h3>_x000D_
  <div ng-controller="Ctrl1">_x000D_
    <input type="text" ng-model="value"/>_x000D_
    <button ng-click="update()">Update</button>_x000D_
  </div>_x000D_
  _x000D_
  <hr>_x000D_
  _x000D_
  <h3>Controller 2 Scope</h3>_x000D_
  <div ng-controller="Ctrl2">_x000D_
    Value: {{ value }}_x000D_
  </div>  _x000D_
_x000D_
</div>

_x000D_

C++ calling base class constructors

Imagine it like this: When your sub-class inherits properties from a super-class, they don't magically appear. You still have to construct the object. So, you call the base constructor. Imagine if you class inherits a variable, which your super-class constructor initializes to an important value. If we didn't do this, your code could fail because the variable wasn't initialized.

MS Excel showing the formula in a cell instead of the resulting value

Make sure that...

There's an = sign before the formula
There's no white space before the = sign
There are no quotes around the formula (must be =A1, instead of "=A1")
You're not in formula view (hit Ctrl + ` to switch between modes)
The cell format is set to General instead of Text
If simply changing the format doesn't work, hit F2, Enter
Undoing actions (CTRL+Z) back until the value shows again and then simply redoing all those actions with CTRL-Y also worked for some users

how to print a string to console in c++

"Visual Studio does not support std::cout as debug tool for non-console applications"
_{- from Marius Amado-Alves' answer to "How can I see cout output in a non-console application?"}

Which means if you use it, Visual Studio shows nothing in the "output" window (in my case VS2008)

How do I generate a random int number?

The Random class is used to create random numbers. (Pseudo-random that is of course.).

Example:

Random rnd = new Random();
int month  = rnd.Next(1, 13);  // creates a number between 1 and 12
int dice   = rnd.Next(1, 7);   // creates a number between 1 and 6
int card   = rnd.Next(52);     // creates a number between 0 and 51

If you are going to create more than one random number, you should keep the Random instance and reuse it. If you create new instances too close in time, they will produce the same series of random numbers as the random generator is seeded from the system clock.

google console error `OR-IEH-01`

Recently I was also having this issue, then I contacted Google Support and they gave me this link to provide required info, I posted and within 24 hours my problem was fixed.

Link: https://support.google.com/payments/contact/alt_account_verification

6 digits regular expression

You can use range quantifier {min,max} to specify minimum of 1 digit and maximum of 6 digits as:

^[0-9]{1,6}$

Explanation:

^     : Start anchor
[0-9] : Character class to match one of the 10 digits
{1,6} : Range quantifier. Minimum 1 repetition and maximum 6.
$     : End anchor

Why did your regex not work ?

You were almost close on the regex:

^[0-9][0-9]\?[0-9]\?[0-9]\?[0-9]\?[0-9]\?$

Since you had escaped the ? by preceding it with the \, the ? was no more acting as a regex meta-character ( for 0 or 1 repetitions) but was being treated literally.

To fix it just remove the \ and you are there.

See it on rubular.

The quantifier based regex is shorter, more readable and can easily be extended to any number of digits.

Your second regex:

^[0-999999]$

is equivalent to:

^[0-9]$

which matches strings with exactly one digit. They are equivalent because a character class [aaaab] is same as [ab].

How To Get The Current Year Using Vba

Year(Date)

Year(): Returns the year portion of the date argument.
Date: Current date only.

Explanation of both of these functions from here.

How to download a file using a Java REST service and a data stream

Refer this:

@RequestMapping(value="download", method=RequestMethod.GET)
public void getDownload(HttpServletResponse response) {

// Get your file stream from wherever.
InputStream myStream = someClass.returnFile();

// Set the content type and attachment header.
response.addHeader("Content-disposition", "attachment;filename=myfilename.txt");
response.setContentType("txt/plain");

// Copy the stream to the response's output stream.
IOUtils.copy(myStream, response.getOutputStream());
response.flushBuffer();
}

Details at: https://twilblog.github.io/java/spring/rest/file/stream/2015/08/14/return-a-file-stream-from-spring-rest.html

Accessing SQL Database in Excel-VBA

Suggested changes:

Do not invoke the Command object's Execute method;
Set the Recordset object's Source property to be your Command object;
Invoke the Recordset object's Open method with no parameters;
Remove the parentheses from around the Recordset object in the call to CopyFromRecordset;
Actually declare your variables :)

Revised code:

Sub GetDataFromADO()

    'Declare variables'
        Dim objMyConn As ADODB.Connection
        Dim objMyCmd As ADODB.Command
        Dim objMyRecordset As ADODB.Recordset

        Set objMyConn = New ADODB.Connection
        Set objMyCmd = New ADODB.Command
        Set objMyRecordset = New ADODB.Recordset

    'Open Connection'
        objMyConn.ConnectionString = "Provider=SQLOLEDB;Data Source=localhost;User ID=abc;Password=abc;"    
        objMyConn.Open

    'Set and Excecute SQL Command'
        Set objMyCmd.ActiveConnection = objMyConn
        objMyCmd.CommandText = "select * from mytable"
        objMyCmd.CommandType = adCmdText

    'Open Recordset'
        Set objMyRecordset.Source = objMyCmd
        objMyRecordset.Open

    'Copy Data to Excel'
        ActiveSheet.Range("A1").CopyFromRecordset objMyRecordset

End Sub

ADB server version (36) doesn't match this client (39) {Not using Genymotion}

I had the same error. In my case, using Appium, I had two versions of ADB

$ /usr/local/bin/adb version 36

and

$ /Users/user/Library/Android/sdk/platform-tools/adb version 39

The solution was:

be sure that your $PATH in bash_profile is pointing to: /Users/user/Library/Android/sdk/platform-tools/
stop the adb server: adb kill-server and check Appium is stopped.
delete the adb version 36 (or you can rename it to have a backup): rm /usr/local/bin/adb
start adb server: adb start-server or just starting Appium

ping response "Request timed out." vs "Destination Host unreachable"

As I understand it, "request timeout" means the ICMP packet reached from one host to the other host but the reply could not reach the requesting host. There may be more packet loss or some physical issue. "destination host unreachable" means there is no proper route defined between two hosts.

Linear regression with matplotlib / numpy

arange generates lists (well, numpy arrays); type help(np.arange) for the details. You don't need to call it on existing lists.

>>> x = [1,2,3,4]
>>> y = [3,5,7,9] 
>>> 
>>> m,b = np.polyfit(x, y, 1)
>>> m
2.0000000000000009
>>> b
0.99999999999999833

I should add that I tend to use poly1d here rather than write out "m*x+b" and the higher-order equivalents, so my version of your code would look something like this:

import numpy as np
import matplotlib.pyplot as plt

x = [1,2,3,4]
y = [3,5,7,10] # 10, not 9, so the fit isn't perfect

coef = np.polyfit(x,y,1)
poly1d_fn = np.poly1d(coef) 
# poly1d_fn is now a function which takes in x and returns an estimate for y

plt.plot(x,y, 'yo', x, poly1d_fn(x), '--k')
plt.xlim(0, 5)
plt.ylim(0, 12)

Increasing heap space in Eclipse: (java.lang.OutOfMemoryError)

In Run->Run Configuration find the Name of the class you have been running, select it, click the Arguments tab then add:

-Xms512M -Xmx1524M

to the VM Arguments section

How do I get the browser scroll position in jQuery?

Since it appears you are using jQuery, here is a jQuery solution.

$(function() {
    $('#Eframe').on("mousewheel", function() {
        alert($(document).scrollTop());
    });
});

Not much to explain here. If you want, here is the jQuery documentation.

View/edit ID3 data for MP3 files

TagLib Sharp is pretty popular.

As a side note, if you wanted to take a quick and dirty peek at doing it yourself.. here is a C# snippet I found to read an mp3's tag info.

class MusicID3Tag

{

    public byte[] TAGID = new byte[3];      //  3
    public byte[] Title = new byte[30];     //  30
    public byte[] Artist = new byte[30];    //  30 
    public byte[] Album = new byte[30];     //  30 
    public byte[] Year = new byte[4];       //  4 
    public byte[] Comment = new byte[30];   //  30 
    public byte[] Genre = new byte[1];      //  1

}

string filePath = @"C:\Documents and Settings\All Users\Documents\My Music\Sample Music\041105.mp3";

        using (FileStream fs = File.OpenRead(filePath))
        {
            if (fs.Length >= 128)
            {
                MusicID3Tag tag = new MusicID3Tag();
                fs.Seek(-128, SeekOrigin.End);
                fs.Read(tag.TAGID, 0, tag.TAGID.Length);
                fs.Read(tag.Title, 0, tag.Title.Length);
                fs.Read(tag.Artist, 0, tag.Artist.Length);
                fs.Read(tag.Album, 0, tag.Album.Length);
                fs.Read(tag.Year, 0, tag.Year.Length);
                fs.Read(tag.Comment, 0, tag.Comment.Length);
                fs.Read(tag.Genre, 0, tag.Genre.Length);
                string theTAGID = Encoding.Default.GetString(tag.TAGID);

                if (theTAGID.Equals("TAG"))
                {
                    string Title = Encoding.Default.GetString(tag.Title);
                    string Artist = Encoding.Default.GetString(tag.Artist);
                    string Album = Encoding.Default.GetString(tag.Album);
                    string Year = Encoding.Default.GetString(tag.Year);
                    string Comment = Encoding.Default.GetString(tag.Comment);
                    string Genre = Encoding.Default.GetString(tag.Genre);

                    Console.WriteLine(Title);
                    Console.WriteLine(Artist);
                    Console.WriteLine(Album);
                    Console.WriteLine(Year);
                    Console.WriteLine(Comment);
                    Console.WriteLine(Genre);
                    Console.WriteLine();
                }
            }
        }

Pandas - How to flatten a hierarchical index in columns

The easiest and most intuitive solution for me was to combine the column names using get_level_values. This prevents duplicate column names when you do more than one aggregation on the same column:

level_one = df.columns.get_level_values(0).astype(str)
level_two = df.columns.get_level_values(1).astype(str)
df.columns = level_one + level_two

If you want a separator between columns, you can do this. This will return the same thing as Seiji Armstrong's comment on the accepted answer that only includes underscores for columns with values in both index levels:

level_one = df.columns.get_level_values(0).astype(str)
level_two = df.columns.get_level_values(1).astype(str)
column_separator = ['_' if x != '' else '' for x in level_two]
df.columns = level_one + column_separator + level_two

I know this does the same thing as Andy Hayden's great answer above, but I think it is a bit more intuitive this way and is easier to remember (so I don't have to keep referring to this thread), especially for novice pandas users.

This method is also more extensible in the case where you may have 3 column levels.

level_one = df.columns.get_level_values(0).astype(str)
level_two = df.columns.get_level_values(1).astype(str)
level_three = df.columns.get_level_values(2).astype(str)
df.columns = level_one + level_two + level_three

Vue js error: Component template should contain exactly one root element

Component template should contain exactly one root element. If you are using v-if on multiple elements, use v-else-if to chain them instead.

The right approach is

<template>
  <div> <!-- The root -->
    <p></p> 
    <p></p>
  </div>
</template>

The wrong approach

<template> <!-- No root Element -->
    <p></p> 
    <p></p>
</template>

Multi Root Components

The way around to that problem is using functional components, they are components where you have to pass no reactive data means component will not be watching for any data changes as well as not updating it self when something in parent component changes.

As this is a work around it comes with a price, functional components don't have any life cycle hooks passed to it, they are instance less as well you cannot refer to this anymore and everything is passed with context.

Here is how you can create a simple functional component.

Vue.component('my-component', {
    // you must set functional as true
  functional: true,
  // Props are optional
  props: {
    // ...
  },
  // To compensate for the lack of an instance,
  // we are now provided a 2nd context argument.
  render: function (createElement, context) {
    // ...
  }
})

Now that we have covered functional components in some detail lets cover how to create multi root components, for that I am gonna present you with a generic example.

<template>
 <ul>
     <NavBarRoutes :routes="persistentNavRoutes"/>
     <NavBarRoutes v-if="loggedIn" :routes="loggedInNavRoutes" />
     <NavBarRoutes v-else :routes="loggedOutNavRoutes" />
 </ul>
</template>

Now if we take a look at NavBarRoutes template

<template>
 <li
 v-for="route in routes"
 :key="route.name"
 >
 <router-link :to="route">
 {{ route.title }}
 </router-link>
 </li>
</template>

We cant do some thing like this we will be violating single root component restriction

Solution Make this component functional and use render

{
functional: true,
render(h, { props }) {
 return props.routes.map(route =>
  <li key={route.name}>
    <router-link to={route}>
      {route.title}
    </router-link>
  </li>
 )
}

Here you have it you have created a multi root component, Happy coding

Reference for more details visit: https://blog.carbonteq.com/vuejs-create-multi-root-components/

Correctly Parsing JSON in Swift 3

let str = "{\"names\": [\"Bob\", \"Tim\", \"Tina\"]}"

let data = str.data(using: String.Encoding.utf8, allowLossyConversion: false)!

do {
    let json = try JSONSerialization.jsonObject(with: data, options: []) as! [String: AnyObject]
    if let names = json["names"] as? [String] 
{
        print(names)
}
} catch let error as NSError {
    print("Failed to load: \(error.localizedDescription)")
}

Using Server.MapPath in external C# Classes in ASP.NET

you can also use:

var path = System.Web.Hosting.HostingEnvironment.MapPath("~/App_Data/myfile.txt")

var path = Server.MapPath("~/App_Data");
var fullpath = Path.Combine(path , "myfile.txt");

is inaccessible

VBA changing active workbook

Use ThisWorkbook which will refer to the original workbook which holds the code.

Alternatively at code start

Dim Wb As Workbook
Set Wb = ActiveWorkbook

sample code that activates all open books before returning to ThisWorkbook

Sub Test()
Dim Wb As Workbook
Dim Wb2 As Workbook
Set Wb = ThisWorkbook
For Each Wb2 In Application.Workbooks
    Wb2.Activate
Next
Wb.Activate
End Sub

How to remove hashbang from url?

Hash is a default vue-router mode setting, it is set because with hash, application doesn't need to connect server to serve the url. To change it you should configure your server and set the mode to HTML5 History API mode.

For server configuration this is the link to help you set up Apache, Nginx and Node.js servers:

https://router.vuejs.org/guide/essentials/history-mode.html

Then you should make sure, that vue router mode is set like following:

vue-router version 2.x

const router = new VueRouter({
  mode: 'history',
  routes: [...]
})

To be clear, these are all vue-router modes you can choose: "hash" | "history" | "abstract".

convert epoch time to date

Please take care that the epoch time is in second and Date object accepts Long value which is in milliseconds. Hence you would have to multiply epoch value with 1000 to use it as long value . Like below :-

SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddhhmmss");
sdf.setTimeZone(TimeZone.getTimeZone(timeZone));
Long dateLong=Long.parseLong(sdf.format(epoch*1000));

Hide axis values but keep axis tick labels in matplotlib

If you use the matplotlib object-oriented approach, this is a simple task using ax.set_xticklabels() and ax.set_yticklabels():

import matplotlib.pyplot as plt

# Create Figure and Axes instances
fig,ax = plt.subplots(1)

# Make your plot, set your axes labels
ax.plot(sim_1['t'],sim_1['V'],'k')
ax.set_ylabel('V')
ax.set_xlabel('t')

# Turn off tick labels
ax.set_yticklabels([])
ax.set_xticklabels([])

plt.show()

Generics in C#, using type of a variable as parameter

I'm not sure whether I understand your question correctly, but you can write your code in this way:

bool DoesEntityExist<T>(T instance, ....)

You can call the method in following fashion:

DoesEntityExist(myTypeInstance, ...)

This way you don't need to explicitly write the type, the framework will overtake the type automatically from the instance.

How to delete columns in numpy.array

>>> A = array([[ 1,  2,  3,  4],
               [ 5,  6,  7,  8],
               [ 9, 10, 11, 12]])

>>> A = A.transpose()

>>> A = A[1:].transpose()

How to find the last field using 'cut'

An alternative using perl would be:

perl -pe 's/(.*) (.*)$/$2/' file

where you may change \t for whichever the delimiter of file is

WampServer: php-win.exe The program can't start because MSVCR110.dll is missing

During the download of wamp server from wampserver website you get a warning..

WARNING : Vous devez avoir installé Visual Studio 2012 : VC 11 vcredist_x64/86.exe Visual Studio 2012 VC 11 vcredist_x64/86.exe : http://www.microsoft.com/en-us/download/details.aspx?id=30679

So if you install the vcredist_xxx.exe it will be ok

Java: Get month Integer from Date

If you can't use Joda time and you still live in the dark world :) ( Java 5 or lower ) you can enjoy this :

Note: Make sure your date is allready made by the format : dd/MM/YYYY

/**
Make an int Month from a date
*/
public static int getMonthInt(Date date) {

    SimpleDateFormat dateFormat = new SimpleDateFormat("MM");
    return Integer.parseInt(dateFormat.format(date));
}

/**
Make an int Year from a date
*/
public static int getYearInt(Date date) {

    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy");
    return Integer.parseInt(dateFormat.format(date));
}

How to install older version of node.js on Windows?

Go here and find the version you want to install and then download the correct msi file and run the installer. You cannot install node by running this command, also the error you receive is stating that npm is not on your path which suggests machine doesn't currently have node installed on it

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

Failed to decode downloaded font

In my case -- using React with Gatsby -- the issue was solved with double-checking all of my paths. I was using React/Gatsby with Sass and the Gatsby source files were looking for the fonts in a different place than the compiled files. Once I duplicated the files into each path this problem was gone.

How to build a Horizontal ListView with RecyclerView?

Try this:

myrecyclerview.setLayoutManager(
        new LinearLayoutManager(getActivity(),
                                LinearLayoutManager.HORIZONTAL,false));
myrecyclerview.setAdapter(recyclerAdapter);

only in case you got a recycler view with some fragments on it.

How are environment variables used in Jenkins with Windows Batch Command?

I should this On Windows, environment variable expansion is %BUILD_NUMBER%

How to check whether a pandas DataFrame is empty?

To see if a dataframe is empty, I argue that one should test for the length of a dataframe's columns index:

if len(df.columns) == 0: 1

Reason:

According to the Pandas Reference API, there is a distinction between:

an empty dataframe with 0 rows and 0 columns
an empty dataframe with rows containing NaN hence at least 1 column

Arguably, they are not the same. The other answers are imprecise in that df.empty, len(df), or len(df.index) make no distinction and return index is 0 and empty is True in both cases.

Examples

Example 1: An empty dataframe with 0 rows and 0 columns

In [1]: import pandas as pd
        df1 = pd.DataFrame()
        df1
Out[1]: Empty DataFrame
        Columns: []
        Index: []

In [2]: len(df1.index)  # or len(df1)
Out[2]: 0

In [3]: df1.empty
Out[3]: True

Example 2: A dataframe which is emptied to 0 rows but still retains n columns

In [4]: df2 = pd.DataFrame({'AA' : [1, 2, 3], 'BB' : [11, 22, 33]})
        df2
Out[4]:    AA  BB
        0   1  11
        1   2  22
        2   3  33

In [5]: df2 = df2[df2['AA'] == 5]
        df2
Out[5]: Empty DataFrame
        Columns: [AA, BB]
        Index: []

In [6]: len(df2.index)  # or len(df2)
Out[6]: 0

In [7]: df2.empty
Out[7]: True

Now, building on the previous examples, in which the index is 0 and empty is True. When reading the length of the columns index for the first loaded dataframe df1, it returns 0 columns to prove that it is indeed empty.

In [8]: len(df1.columns)
Out[8]: 0

In [9]: len(df2.columns)
Out[9]: 2

Critically, while the second dataframe df2 contains no data, it is not completely empty because it returns the amount of empty columns that persist.

Why it matters

Let's add a new column to these dataframes to understand the implications:

# As expected, the empty column displays 1 series
In [10]: df1['CC'] = [111, 222, 333]
         df1
Out[10]:    CC
         0 111
         1 222
         2 333
In [11]: len(df1.columns)
Out[11]: 1

# Note the persisting series with rows containing `NaN` values in df2
In [12]: df2['CC'] = [111, 222, 333]
         df2
Out[12]:    AA  BB   CC
         0 NaN NaN  111
         1 NaN NaN  222
         2 NaN NaN  333
In [13]: len(df2.columns)
Out[13]: 3

It is evident that the original columns in df2 have re-surfaced. Therefore, it is prudent to instead read the length of the columns index with len(pandas.core.frame.DataFrame.columns) to see if a dataframe is empty.

Practical solution

# New dataframe df
In [1]: df = pd.DataFrame({'AA' : [1, 2, 3], 'BB' : [11, 22, 33]})
        df
Out[1]:    AA  BB
        0   1  11
        1   2  22
        2   3  33

# This data manipulation approach results in an empty df
# because of a subset of values that are not available (`NaN`)
In [2]: df = df[df['AA'] == 5]
        df
Out[2]: Empty DataFrame
        Columns: [AA, BB]
        Index: []

# NOTE: the df is empty, BUT the columns are persistent
In [3]: len(df.columns)
Out[3]: 2

# And accordingly, the other answers on this page
In [4]: len(df.index)  # or len(df)
Out[4]: 0

In [5]: df.empty
Out[5]: True

# SOLUTION: conditionally check for empty columns
In [6]: if len(df.columns) != 0:  # <--- here
            # Do something, e.g. 
            # drop any columns containing rows with `NaN`
            # to make the df really empty
            df = df.dropna(how='all', axis=1)
        df
Out[6]: Empty DataFrame
        Columns: []
        Index: []

# Testing shows it is indeed empty now
In [7]: len(df.columns)
Out[7]: 0

Adding a new data series works as expected without the re-surfacing of empty columns (factually, without any series that were containing rows with only NaN):

In [8]: df['CC'] = [111, 222, 333]
         df
Out[8]:    CC
         0 111
         1 222
         2 333
In [9]: len(df.columns)
Out[9]: 1

CSS way to horizontally align table

style="text-align:center;"

(i think)

or you could just ignore it, it still works

How can I reorder my divs using only CSS?

Negative top margins can achieve this effect, but they would need to be customized for each page. For instance, this markup...

<div class="product">
<h2>Greatest Product Ever</h2>
<p class="desc">This paragraph appears in the source code directly after the heading and will appear in the search results.</p>
<p class="sidenote">Note: This information appears in HTML after the product description appearing below.</p>
</div>

...and this CSS...

.product { width: 400px; }
.desc { margin-top: 5em; }
.sidenote { margin-top: -7em; }

...would allow you to pull the second paragraph above the first.

Of course, you'll have to manually tweak your CSS for different description lengths so that the intro paragraph jumps up the appropriate amount, but if you have limited control over the other parts and full control over markup and CSS then this might be an option.

Bootstrap datepicker disabling past dates without current date

HTML

<input type="text" name="my_date" value="4/26/2015" class="datepicker">

jQuery(function() {
  var datepicker = $('input.datepicker');

  if (datepicker.length > 0) {
    datepicker.datepicker({
      format: "mm/dd/yyyy",
      startDate: new Date()
    });
  }
});

That will highlight the default date as 4/26/2015 (Apr 26, 2015) in the calendar when opened and disable all the dates before current date.

Failure [INSTALL_FAILED_ALREADY_EXISTS] when I tried to update my application

You are getting that error because an application with a package name same as your application already exists. If you are sure that you have not installed the same application before, change the package name and try.

Else wise, here is what you can do:

Uninstall the application from the device: Go to Settings -> Manage Applications and choose Uninstall OR
Uninstall the app using adb command line interface: type adb uninstall After you are done with this step, try installing the application again.

Hexadecimal To Decimal in Shell Script

To convert from hex to decimal, there are many ways to do it in the shell or with an external program:

With bash:

$ echo $((16#FF))
255

with bc:

$ echo "ibase=16; FF" | bc
255

with perl:

$ perl -le 'print hex("FF");'
255

with printf :

$ printf "%d\n" 0xFF
255

with python:

$ python -c 'print(int("FF", 16))'
255

with ruby:

$ ruby -e 'p "FF".to_i(16)'
255

with node.js:

$ nodejs <<< "console.log(parseInt('FF', 16))"
255

with rhino:

$ rhino<<EOF
print(parseInt('FF', 16))
EOF
...
255

with groovy:

$ groovy -e 'println Integer.parseInt("FF",16)'
255

Using multiple case statements in select query

There are two ways to write case statements, you seem to be using a combination of the two

case a.updatedDate
    when 1760 then 'Entered on' + a.updatedDate
    when 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

case 
    when a.updatedDate = 1760 then 'Entered on' + a.updatedDate
    when a.updatedDate = 1710 then 'Viewed on' + a.updatedDate
    else 'Last Updated on' + a.updateDate
end

are equivalent. They may not work because you may need to convert date types to varchars to append them to other varchars.

Convert regular Python string to raw string

Just simply use the encode function.

my_var = 'hello'
my_var_bytes = my_var.encode()
print(my_var_bytes)

And then to convert it back to a regular string do this

my_var_bytes = 'hello'
my_var = my_var_bytes.decode()
print(my_var)

--EDIT--

The following does not make the string raw but instead encodes it to bytes and decodes it.

Simple WPF RadioButton Binding?

I know it's way way overdue, but I have an alternative solution, which is lighter and simpler. Derive a class from System.Windows.Controls.RadioButton and declare two dependency properties RadioValue and RadioBinding. Then in the class code, override OnChecked and set the RadioBinding property value to that of the RadioValue property value. In the other direction, trap changes to the RadioBinding property using a callback, and if the new value is equal to the value of the RadioValue property, set its IsChecked property to true.

Here's the code:

public class MyRadioButton : RadioButton
{
    public object RadioValue
    {
        get { return (object)GetValue(RadioValueProperty); }
        set { SetValue(RadioValueProperty, value); }
    }

    // Using a DependencyProperty as the backing store for RadioValue.
       This enables animation, styling, binding, etc...
    public static readonly DependencyProperty RadioValueProperty =
        DependencyProperty.Register(
            "RadioValue", 
            typeof(object), 
            typeof(MyRadioButton), 
            new UIPropertyMetadata(null));

    public object RadioBinding
    {
        get { return (object)GetValue(RadioBindingProperty); }
        set { SetValue(RadioBindingProperty, value); }
    }

    // Using a DependencyProperty as the backing store for RadioBinding.
       This enables animation, styling, binding, etc...
    public static readonly DependencyProperty RadioBindingProperty =
        DependencyProperty.Register(
            "RadioBinding", 
            typeof(object), 
            typeof(MyRadioButton), 
            new FrameworkPropertyMetadata(
                null, 
                FrameworkPropertyMetadataOptions.BindsTwoWayByDefault, 
                OnRadioBindingChanged));

    private static void OnRadioBindingChanged(
        DependencyObject d,
        DependencyPropertyChangedEventArgs e)
    {
        MyRadioButton rb = (MyRadioButton)d;
        if (rb.RadioValue.Equals(e.NewValue))
            rb.SetCurrentValue(RadioButton.IsCheckedProperty, true);
    }

    protected override void OnChecked(RoutedEventArgs e)
    {
        base.OnChecked(e);
        SetCurrentValue(RadioBindingProperty, RadioValue);
    }
}

XAML usage:

<my:MyRadioButton GroupName="grp1" Content="Value 1"
    RadioValue="val1" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 2"
    RadioValue="val2" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 3"
    RadioValue="val3" RadioBinding="{Binding SelectedValue}"/>
<my:MyRadioButton GroupName="grp1" Content="Value 4"
    RadioValue="val4" RadioBinding="{Binding SelectedValue}"/>

Hope someone finds this useful after all this time :)

How to order results with findBy() in Doctrine

$ens = $em->getRepository('AcmeBinBundle:Marks')
              ->findBy(
                 array(), 
                 array('id' => 'ASC')
               );

Why doesn't [01-12] range work as expected?

The []s in a regex denote a character class. If no ranges are specified, it implicitly ors every character within it together. Thus, [abcde] is the same as (a|b|c|d|e), except that it doesn't capture anything; it will match any one of a, b, c, d, or e. All a range indicates is a set of characters; [ac-eg] says "match any one of: a; any character between c and e; or g". Thus, your match says "match any one of: 0; any character between 1 and 1 (i.e., just 1); or 2.

Your goal is evidently to specify a number range: any number between 01 and 12 written with two digits. In this specific case, you can match it with 0[1-9]|1[0-2]: either a 0 followed by any digit between 1 and 9, or a 1 followed by any digit between 0 and 2. In general, you can transform any number range into a valid regex in a similar manner. There may be a better option than regular expressions, however, or an existing function or module which can construct the regex for you. It depends on your language.

iPhone and WireShark

I recommend Charles Web Proxy

Charles is an HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet. This includes requests, responses and the HTTP headers (which contain the cookies and caching information).

SSL Proxying – view SSL requests and responses in plain text
Bandwidth Throttling to simulate slower Internet connections including latency
AJAX debugging – view XML and JSON requests and responses as a tree or as text
AMF – view the contents of Flash Remoting / Flex Remoting messages as a tree
Repeat requests to test back-end changes, Edit requests to test different inputs
Breakpoints to intercept and edit requests or responses
Validate recorded HTML, CSS and RSS/atom responses using the W3C validator

It's cross-platform, written in JAVA, and pretty good. Not nearly as overwhelming as Wireshark, and does a lot of the annoying stuff like setting up the proxies, etc. for you. The only bad part is that it costs money, $50 at that. Not cheap, but a useful tool.

Formatting ISODate from Mongodb

// from MongoDate object to Javascript Date object

var MongoDate = {sec: 1493016016, usec: 650000};
var dt = new Date("1970-01-01T00:00:00+00:00");
    dt.setSeconds(MongoDate.sec);

How to list npm user-installed packages?

Use npm list and filter by contains using grep

Example:

npm list -g | grep name-of-package

How to find patterns across multiple lines using grep?

While the sed option is the simplest and easiest, LJ's one-liner is sadly not the most portable. Those stuck with a version of the C Shell will need to escape their bangs:

sed -e '/abc/,/efg/\!d' [file]

This unfortunately does not work in bash et al.

How to remove html special chars?

A plain vanilla strings way to do it without engaging the preg regex engine:

function remEntities($str) {
  if(substr_count($str, '&') && substr_count($str, ';')) {
    // Find amper
    $amp_pos = strpos($str, '&');
    //Find the ;
    $semi_pos = strpos($str, ';');
    // Only if the ; is after the &
    if($semi_pos > $amp_pos) {
      //is a HTML entity, try to remove
      $tmp = substr($str, 0, $amp_pos);
      $tmp = $tmp. substr($str, $semi_pos + 1, strlen($str));
      $str = $tmp;
      //Has another entity in it?
      if(substr_count($str, '&') && substr_count($str, ';'))
        $str = remEntities($tmp);
    }
  }
  return $str;
}

Default FirebaseApp is not initialized

Installed Firebase Via Android Studio Tools...Firebase...

I did the installation via the built-in tools from Android Studio (following the latest docs from Firebase). This installed the basic dependencies but when I attempted to connect to the database it always gave me the error that I needed to call initialize first, even though I was:

Default FirebaseApp is not initialized in this process . Make sure to call FirebaseApp.initializeApp(Context) first.

I was getting this error no matter what I did.

Finally, after seeing a comment in one of the other answers I changed the following in my gradle from version 4.1.0 to :

classpath 'com.google.gms:google-services:4.0.1'

When I did that I finally saw an error that helped me:

File google-services.json is missing. The Google Services Plugin cannot function without it. Searched Location: C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\src\nullnull\debug\google-services.json
C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\src\debug\nullnull\google-services.json
C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\src\nullnull\google-services.json
C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\src\debug\google-services.json
C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\src\nullnullDebug\google-services.json
C:\Users\%username%\AndroidStudioProjects\TxtFwd\app\google-services.json

That's the problem. It seems that the 4.1.0 version doesn't give that build error for some reason -- doesn't mention that you have a missing google-services.json file. I don't have the google-services.json file in my app so I went out and added it.

But since this was an upgrade which used an existing realtime firsbase database I had never had to generate that file in the past. I went to firebase and generated it and added it and it fixed the problem.

Changed Back to 4.1.0

Once I discovered all of this then I changed the classpath variable back (to 4.1.0) and rebuilt and it crashed again with the error that it hasn't been initalized.

Root Issues

Building with 4.1.0 doesn't provide you with a valid error upon precompile so you may not know what is going on.
Running against 4.1.0 causes the initialization error.

Convert a string representation of a hex dump to a byte array using Java?

For what it's worth, here's another version which supports odd length strings, without resorting to string concatenation.

public static byte[] hexStringToByteArray(String input) {
    int len = input.length();

    if (len == 0) {
        return new byte[] {};
    }

    byte[] data;
    int startIdx;
    if (len % 2 != 0) {
        data = new byte[(len / 2) + 1];
        data[0] = (byte) Character.digit(input.charAt(0), 16);
        startIdx = 1;
    } else {
        data = new byte[len / 2];
        startIdx = 0;
    }

    for (int i = startIdx; i < len; i += 2) {
        data[(i + 1) / 2] = (byte) ((Character.digit(input.charAt(i), 16) << 4)
                + Character.digit(input.charAt(i+1), 16));
    }
    return data;
}

How to detect a docker daemon port

By default, the docker daemon will use the unix socket unix:///var/run/docker.sock (you can check this is the case for you by doing a sudo netstat -tunlp and note that there is no docker daemon process listening on any ports). It's recommended to keep this setting for security reasons but it sounds like Riak requires the daemon to be running on a TCP socket.

To start the docker daemon with a TCP socket that anybody can connect to, use the -H option:

sudo docker -H 0.0.0.0:2375 -d &

Warning: This means machines that can talk to the daemon through that TCP socket can get root access to your host machine.

https://docs.docker.com/install/linux/linux-postinstall/#configure-where-the-docker-daemon-listens-for-connections

How to replace text of a cell based on condition in excel

You can use the IF statement in a new cell to replace text, such as:

=IF(A4="C", "Other", A4)

This will check and see if cell value A4 is "C", and if it is, it replaces it with the text "Other"; otherwise, it uses the contents of cell A4.

EDIT

Assuming that the Employee_Count values are in B1-B10, you can use this:

=IF(B1=LARGE($B$1:$B$10, 10), "Other", B1)

This function doesn't even require the data to be sorted; the LARGE function will find the 10th largest number in the series, and then the rest of the formula will compare against that.

How to submit a form with JavaScript by clicking a link?

HTML & CSS - No Javascript Solution

Make your button appear like a Bootstrap link

HTML:

<form>
    <button class="btn-link">Submit</button>
</form>

CSS:

.btn-link {

    background: none;
    border: none;
    padding: 0px;
    color: #3097D1;
    font: inherit;

}

.btn-link:hover {

    color: #216a94;
    text-decoration: underline;

}

Find files with size in Unix

Assuming you have GNU find:

find . -size +10000k -printf '%s %f\n'

If you want a constant width for the size field, you can do something like:

find . -size +10000k -printf '%10s %f\n'

Note that -size +1000k selects files of at least 10,240,000 bytes (k is 1024, not 1000). You said in a comment that you want files bigger than 1M; if that's 1024*1024 bytes, then this:

find . -size +1M ...

will do the trick -- except that it will also print the size and name of files that are exactly 1024*1024 bytes. If that matters, you could use:

find . -size +1048575c ...

You need to decide just what criterion you want.

How to count the NaN values in a column in pandas DataFrame

You can use the isna() method (or it's alias isnull() which is also compatible with older pandas versions < 0.21.0) and then sum to count the NaN values. For one column:

In [1]: s = pd.Series([1,2,3, np.nan, np.nan])

In [4]: s.isna().sum()   # or s.isnull().sum() for older pandas versions
Out[4]: 2

For several columns, it also works:

In [5]: df = pd.DataFrame({'a':[1,2,np.nan], 'b':[np.nan,1,np.nan]})

In [6]: df.isna().sum()
Out[6]:
a    1
b    2
dtype: int64

How to hide a div element depending on Model value? MVC

The below code should apply different CSS classes based on your Model's CanEdit Property value .

<div class="@(Model.CanEdit?"visible-item":"hidden-item")">Some links</div>

But if it is something important like Edit/Delete links, you shouldn't be simply hiding,because people can update the css class/HTML markup in their browser and get access to your important link. Instead you should be simply not Rendering the important stuff to the browser.

@if(Model.CanEdit)
{
  <div>Edit/Delete link goes here</div>
}

How to convert a char array back to a string?

You can also use StringBuilder class

String b = new StringBuilder(a).toString();

Use of String or StringBuilder varies with your method requirements.

How to start Activity in adapter?

Just pass in the current Context to the Adapter constructor and store it as a field. Then inside the onClick you can use that context to call startActivity().

pseudo-code

public class MyAdapter extends Adapter {
     private Context context;

     public MyAdapter(Context context) {
          this.context = context;     
     }

     public View getView(...){
         View v;
         v.setOnClickListener(new OnClickListener() {
             void onClick() {
                 context.startActivity(...);
             }
         });
     }
}

Finding the index of an item in a list

For one comparable

# Throws ValueError if nothing is found
some_list = ['foo', 'bar', 'baz'].index('baz')
# some_list == 2

Custom predicate

some_list = [item1, item2, item3]

# Throws StopIteration if nothing is found
# *unless* you provide a second parameter to `next`
index_of_value_you_like = next(
    i for i, item in enumerate(some_list)
    if item.matches_your_criteria())

Finding index of all items by predicate

index_of_staff_members = [
    i for i, user in enumerate(users)
    if user.is_staff()]

Can I have a video with transparent background using HTML5 video tag?

Mp4 files can be playable with transparent background using seeThrou Js library. All you need to combine actual video and alpha channel in the single video. Also make sure to keep video height dimension below 1400 px as some of the old iphone devices wont play videos with dimension more than 2000. This is pretty useful in safari desktop and mobile devices which doesnt support webm at this time.

more details can be found in the below link https://github.com/m90/seeThru

Angular 2 beta.17: Property 'map' does not exist on type 'Observable<Response>'

You need to import the map operator:

import 'rxjs/add/operator/map'

Copying PostgreSQL database to another server

Accepted answer is correct, but if you want to avoid entering the password interactively, you can use this:

PGPASSWORD={{export_db_password}} pg_dump --create -h {{export_db_host}} -U {{export_db_user}} {{export_db_name}} | PGPASSWORD={{import_db_password}} psql -h {{import_db_host}} -U {{import_db_user}} {{import_db_name}}

Converting strings to floats in a DataFrame

You can try df.column_name = df.column_name.astype(float). As for the NaN values, you need to specify how they should be converted, but you can use the .fillna method to do it.

Example:

In [12]: df
Out[12]: 
     a    b
0  0.1  0.2
1  NaN  0.3
2  0.4  0.5

In [13]: df.a.values
Out[13]: array(['0.1', nan, '0.4'], dtype=object)

In [14]: df.a = df.a.astype(float).fillna(0.0)

In [15]: df
Out[15]: 
     a    b
0  0.1  0.2
1  0.0  0.3
2  0.4  0.5

In [16]: df.a.values
Out[16]: array([ 0.1,  0. ,  0.4])

Pandas read_sql with parameters

The read_sql docs say this params argument can be a list, tuple or dict (see docs).

To pass the values in the sql query, there are different syntaxes possible: ?, :1, :name, %s, %(name)s (see PEP249).
But not all of these possibilities are supported by all database drivers, which syntax is supported depends on the driver you are using (psycopg2 in your case I suppose).

In your second case, when using a dict, you are using 'named arguments', and according to the psycopg2 documentation, they support the %(name)s style (and so not the :name I suppose), see http://initd.org/psycopg/docs/usage.html#query-parameters.
So using that style should work:

df = psql.read_sql(('select "Timestamp","Value" from "MyTable" '
                     'where "Timestamp" BETWEEN %(dstart)s AND %(dfinish)s'),
                   db,params={"dstart":datetime(2014,6,24,16,0),"dfinish":datetime(2014,6,24,17,0)},
                   index_col=['Timestamp'])

Is there a Newline constant defined in Java like Environment.Newline in C#?

Be aware that this property isn't as useful as many people think it is. Just because your app is running on a Windows machine, for example, doesn't mean the file it's reading will be using Windows-style line separators. Many web pages contain a mixture of "\n" and "\r\n", having been cobbled together from disparate sources. When you're reading text as a series of logical lines, you should always look for all three of the major line-separator styles: Windows ("\r\n"), Unix/Linux/OSX ("\n") and pre-OSX Mac ("\r").

When you're writing text, you should be more concerned with how the file will be used than what platform you're running on. For example, if you expect people to read the file in Windows Notepad, you should use "\r\n" because it only recognizes the one kind of separator.

Node JS Promise.all and forEach

Just to add to the solution presented, in my case I wanted to fetch multiple data from Firebase for a list of products. Here is how I did it:

useEffect(() => {
  const fn = p => firebase.firestore().doc(`products/${p.id}`).get();
  const actions = data.occasion.products.map(fn);
  const results = Promise.all(actions);
  results.then(data => {
    const newProducts = [];
    data.forEach(p => {
      newProducts.push({ id: p.id, ...p.data() });
    });
    setProducts(newProducts);
  });
}, [data]);

How to tell if string starts with a number with Python?

sometimes, you can use regex

>>> import re
>>> re.search('^\s*[0-9]',"0abc")
<_sre.SRE_Match object at 0xb7722fa8>

How to list the files inside a JAR file?

Here is an example of using Reflections library to recursively scan classpath by regex name pattern augmented with a couple of Guava perks to to fetch resources contents:

Reflections reflections = new Reflections("com.example.package", new ResourcesScanner());
Set<String> paths = reflections.getResources(Pattern.compile(".*\\.template$"));

Map<String, String> templates = new LinkedHashMap<>();
for (String path : paths) {
    log.info("Found " + path);
    String templateName = Files.getNameWithoutExtension(path);
    URL resource = getClass().getClassLoader().getResource(path);
    String text = Resources.toString(resource, StandardCharsets.UTF_8);
    templates.put(templateName, text);
}

This works with both jars and exploded classes.

Increase permgen space

if you found out that the memory settings were not being used and in order to change the memory settings, I used the tomcat7w or tomcat8w in the \bin folder.Then the following should pop up:

tomcat monitor

Click the Java tab and add the arguments.restart tomcat

How to print number with commas as thousands separators?

from Python version 2.6 you can do this:

def format_builtin(n):
    return format(n, ',')

For Python versions < 2.6 and just for your information, here are 2 manual solutions, they turn floats to ints but negative numbers work correctly:

def format_number_using_lists(number):
    string = '%d' % number
    result_list = list(string)
    indexes = range(len(string))
    for index in indexes[::-3][1:]:
        if result_list[index] != '-':
            result_list.insert(index+1, ',')
    return ''.join(result_list)

few things to notice here:

this line: string = '%d' % number beautifully converts a number to a string, it supports negatives and it drops fractions from floats, making them ints;
this slice indexes[::-3] returns each third item starting from the end, so I used another slice [1:] to remove the very last item cuz I don't need a comma after the last number;
this conditional if l[index] != '-' is being used to support negative numbers, do not insert a comma after the minus sign.

And a more hardcore version:

def format_number_using_generators_and_list_comprehensions(number):
    string = '%d' % number
    generator = reversed( 
        [
            value+',' if (index!=0 and value!='-' and index%3==0) else value
            for index,value in enumerate(reversed(string))
        ]
    )
    return ''.join(generator)

Port 80 is being used by SYSTEM (PID 4), what is that?

It sounds like IIS is listening to port 80 for HTTP requests.

Try stopping IIS by going into Control Panel/Administrative Tools/Internet Information Services, right-clicking on Default Web Site, and click on the Stop option in the popup menu, and see if the listener on port 80 has cleared.

How to create a toggle button in Bootstrap

If you want to keep a small code base, and you are only going to be needing the toggle button for a small part of the application. I would suggest instead maintain you're javascript code your self (angularjs, javascript, jquery) and just use plain CSS.

Good toggle button generator: https://proto.io/freebies/onoff/

Check if a radio button is checked jquery

if($("input:radio[name=test]").is(":checked")){
  //Code to append goes here
}

Slack URL to open a channel from browser

Sure you can:

https://<organization>.slack.com/messages/<channel>/

for example: https://tikal.slack.com/messages/general/ (of course that for accessing it, you must be part of the team)

How to use a jQuery plugin inside Vue

You need to use either the globals loader or expose loader to ensure that webpack includes the jQuery lib in your source code output and so that it doesn't throw errors when your use $ in your components.

// example with expose loader:
npm i --save-dev expose-loader

// somewhere, import (require) this jquery, but pipe it through the expose loader
require('expose?$!expose?jQuery!jquery')

If you prefer, you can import (require) it directly within your webpack config as a point of entry, so I understand, but I don't have an example of this to hand

Alternatively, you can use the globals loader like this: https://www.npmjs.com/package/globals-loader

batch to copy files with xcopy

You must specify your file in the copy:

xcopy C:\source\myfile.txt C:\target

Or if you want to copy all txt files for example

xcopy C:\source\*.txt C:\target

What is "X-Content-Type-Options=nosniff"?

It prevents the browser from doing MIME-type sniffing. Most browsers are now respecting this header, including Chrome/Chromium, Edge, IE >= 8.0, Firefox >= 50 and Opera >= 13. See :

https://blogs.msdn.com/b/ie/archive/2008/09/02/ie8-security-part-vi-beta-2-update.aspx?Redirected=true

Sending the new X-Content-Type-Options response header with the value nosniff will prevent Internet Explorer from MIME-sniffing a response away from the declared content-type.

EDIT:

Oh and, that's an HTTP header, not a HTML meta tag option.

Min / Max Validator in Angular 2 Final

I've added a max validation to amd's great answer.

import { Directive, Input, forwardRef } from '@angular/core'
import { NG_VALIDATORS, Validator, AbstractControl, Validators } from '@angular/forms'

/*
 * This is a wrapper for [min] and [max], used to work with template driven forms
 */

@Directive({
  selector: '[min]',
  providers: [{ provide: NG_VALIDATORS, useExisting: MinNumberValidator, multi: true }]
})
export class MinNumberValidator implements Validator {

  @Input() min: number;

  validate(control: AbstractControl): { [key: string]: any } {
    return Validators.min(this.min)(control)
  }
}

@Directive({
  selector: '[max]',
  providers: [{ provide: NG_VALIDATORS, useExisting: MaxNumberValidator, multi: true }]
})
export class MaxNumberValidator implements Validator {

  @Input() max: number;

  validate(control: AbstractControl): { [key: string]: any } {
    return Validators.max(this.max)(control)
  }
}

What is the reason and how to avoid the [FIN, ACK] , [RST] and [RST, ACK]

Here is a rough explanation of the concepts.

[ACK] is the acknowledgement that the previously sent data packet was received.

[FIN] is sent by a host when it wants to terminate the connection; the TCP protocol requires both endpoints to send the termination request (i.e. FIN).

So, suppose

host A sends a data packet to host B
and then host B wants to close the connection.
Host B (depending on timing) can respond with [FIN,ACK] indicating that it received the sent packet and wants to close the session.
Host A should then respond with a [FIN,ACK] indicating that it received the termination request (the ACK part) and that it too will close the connection (the FIN part).

However, if host A wants to close the session after sending the packet, it would only send a [FIN] packet (nothing to acknowledge) but host B would respond with [FIN,ACK] (acknowledges the request and responds with FIN).

Finally, some TCP stacks perform half-duplex termination, meaning that they can send [RST] instead of the usual [FIN,ACK]. This happens when the host actively closes the session without processing all the data that was sent to it. Linux is one operating system which does just this.

You can find a more detailed and comprehensive explanation here.

Testing Private method using mockito

I don't really understand your need to test the private method. The root problem is that your public method has void as return type, and hence you are not able to test your public method. Hence you are forced to test your private method. Is my guess correct??

A few possible solutions (AFAIK):

Mocking your private methods, but still you won't be "actually" testing your methods.
Verify the state of object used in the method. MOSTLY methods either do some processing of the input values and return an output, or change the state of the objects. Testing the objects for the desired state can also be employed.
```
public class A{

SomeClass classObj = null;

public void publicMethod(){
   privateMethod();
}

private void privateMethod(){
     classObj = new SomeClass();
}

}
```
[Here you can test for the private method, by checking the state change of the classObj from null to not null.]

Refactor your code a little (Hope this is not a legacy code). My funda of writing a method is that, one should always return something (a int/ a boolean). The returned value MAY or MAY NOT be used by the implementation, but it will SURELY BE used by the test

code.

public class A
{ 
    public int method(boolean b)
    {
          int nReturn = 0;
          if (b == true)
               nReturn = method1();
          else
               nReturn = method2();
    }

    private int method1() {}

    private int method2() {}

}

Using Pip to install packages to Anaconda Environment

I know the original question was about conda under MacOS. But I would like to share the experience I've had on Ubuntu 20.04.

In my case, the issue was due to an alias defined in ~/.bashrc: alias pip='/usr/bin/pip3'. That alias was taking precedence on everything else.

So for testing purposes I've removed the alias running unalias pip command. Then the corresponding pip of the active conda environment has been executed properly.

The same issue was applicable to python command.

Load vs. Stress testing

Load testing = putting a specified amount of load on the server for certain amount of time. 100 simultaneous users for 10 minutes. Ensure stability of software. Stress testing = increasing the amount of load steadily until the software crashes. 10 simultaneous users increasing every 2 minutes until the server crashes.

To make a comparison to weight lifting: You "max" your weight to see what you can do for 1 rep (stress testing) and then on regular workouts you do 85% of your max value for 3 sets of 10 reps (load testing)

How to enable Logger.debug() in Log4j

You need to set the logger level to the lowest you want to display. For example, if you want to display DEBUG messages, you need to set the logger level to DEBUG.

The Apache log4j manual has a section on Configuration.

Developing for Android in Eclipse: R.java not regenerating

Here's one more answer that I found, after none of the previous 30 answers helped.

I found my issue in the strings.xml file, although it is very very odd. I stripped down my app to bare minimum and this was the only thing that came to light. I can even replicate it on a brand new empty app.

In the strings.xml file, this compiles (and generates the R.java file):

<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">Test_My_App</string>
<string name="action_settings">Settings</string>
<string name="hello_world">Hello world!</string>
</resources>

However, this is not:

<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="hello_world">Hello world</string>
<string name="app_name">My_App</string>
<string name="action_refresh">Refresh</string>
</resources>

The "funny" thins is that I removed the action_settings several days ago. I've cleaned my code since then and never had any issues. I added additional strings to the strings.xml file today and after cleaning the code the wheels came off. Also, if I re-arrange the order of the same 3 string lines, and clean my code, the R.java file does not get re-generated.

There's my solution to my particular issue.

I hope it helps somebody...

How to show loading spinner in jQuery?

I think you are right. This method is too global...

However - it is a good default for when your AJAX call has no effect on the page itself. (background save for example). ( you can always switch it off for a certain ajax call by passing "global":false - see documentation at jquery

When the AJAX call is meant to refresh part of the page, I like my "loading" images to be specific to the refreshed section. I would like to see which part is refreshed.

Imagine how cool it would be if you could simply write something like :

$("#component_to_refresh").ajax( { ... } );

And this would show a "loading" on this section. Below is a function I wrote that handles "loading" display as well but it is specific to the area you are refreshing in ajax.

First, let me show you how to use it

<!-- assume you have this HTML and you would like to refresh 
      it / load the content with ajax -->

<span id="email" name="name" class="ajax-loading">
</span>

<!-- then you have the following javascript --> 

$(document).ready(function(){
     $("#email").ajax({'url':"/my/url", load:true, global:false});
 })

And this is the function - a basic start that you can enhance as you wish. it is very flexible.

jQuery.fn.ajax = function(options)
{
    var $this = $(this);
    debugger;
    function invokeFunc(func, arguments)
    {
        if ( typeof(func) == "function")
        {
            func( arguments ) ;
        }
    }

    function _think( obj, think )
    {
        if ( think )
        {
            obj.html('<div class="loading" style="background: url(/public/images/loading_1.gif) no-repeat; display:inline-block; width:70px; height:30px; padding-left:25px;"> Loading ... </div>');
        }
        else
        {
            obj.find(".loading").hide();
        }
    }

    function makeMeThink( think )
    {
        if ( $this.is(".ajax-loading") )
        {
            _think($this,think);
        }
        else
        {
            _think($this, think);
        }
    }

    options = $.extend({}, options); // make options not null - ridiculous, but still.
    // read more about ajax events
    var newoptions = $.extend({
        beforeSend: function()
        {
            invokeFunc(options.beforeSend, null);
            makeMeThink(true);
        },

        complete: function()
        {
            invokeFunc(options.complete);
            makeMeThink(false);
        },
        success:function(result)
        {
            invokeFunc(options.success);
            if ( options.load )
            {
                $this.html(result);
            }
        }

    }, options);

    $.ajax(newoptions);
};

Threading Example in Android

This is a nice tutorial:

http://android-developers.blogspot.de/2009/05/painless-threading.html

Or this for the UI thread:

http://developer.android.com/guide/faq/commontasks.html#threading

Or here a very practical one:

http://www.androidacademy.com/1-tutorials/43-hands-on/115-threading-with-android-part1

and another one about procceses and threads

http://developer.android.com/guide/components/processes-and-threads.html

How to scroll to specific item using jQuery?

You can use scrollIntoView() method in javascript. just give id.scrollIntoView();

For example

row_5.scrollIntoView();

How to import Swagger APIs into Postman?

The accepted answer is correct but I will rewrite complete steps for java.

I am currently using Swagger V2 with Spring Boot 2 and it's straightforward 3 step process.

Step 1: Add required dependencies in pom.xml file. The second dependency is optional use it only if you need Swagger UI.

        <!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger2 -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger2</artifactId>
            <version>2.9.2</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/io.springfox/springfox-swagger-ui -->
        <dependency>
            <groupId>io.springfox</groupId>
            <artifactId>springfox-swagger-ui</artifactId>
            <version>2.9.2</version>
        </dependency>

Step 2: Add configuration class

@Configuration
@EnableSwagger2
public class SwaggerConfig {

     public static final Contact DEFAULT_CONTACT = new Contact("Usama Amjad", "https://stackoverflow.com/users/4704510/usamaamjad", "[email protected]");
      public static final ApiInfo DEFAULT_API_INFO = new ApiInfo("Article API", "Article API documentation sample", "1.0", "urn:tos",
              DEFAULT_CONTACT, "Apache 2.0", "http://www.apache.org/licenses/LICENSE-2.0", new ArrayList<VendorExtension>());

    @Bean
    public Docket api() {
        Set<String> producesAndConsumes = new HashSet<>();
        producesAndConsumes.add("application/json");
        return new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(DEFAULT_API_INFO)
                .produces(producesAndConsumes)
                .consumes(producesAndConsumes);

    }
}

Step 3: Setup complete and now you need to document APIs in controllers

    @ApiOperation(value = "Returns a list Articles for a given Author", response = Article.class, responseContainer = "List")
    @ApiResponses(value = { @ApiResponse(code = 200, message = "Success"),
            @ApiResponse(code = 404, message = "The resource you were trying to reach is not found") })
    @GetMapping(path = "/articles/users/{userId}")
    public List<Article> getArticlesByUser() {
       // Do your code
    }

Usage:

You can access your Documentation from http://localhost:8080/v2/api-docs just copy it and paste in Postman to import collection.

Optional Swagger UI: You can also use standalone UI without any other rest client via http://localhost:8080/swagger-ui.html and it's pretty good, you can host your documentation without any hassle.

Among $_REQUEST, $_GET and $_POST which one is the fastest?

I'd suggest using $_POST and $_GET explicitly.

Using $_REQUEST should be unnecessary with proper site design anyway, and it comes with some downsides like leaving you open to easier CSRF/XSS attacks and other silliness that comes from storing data in the URL.

The speed difference should be minimal either way.

Gradle, Android and the ANDROID_HOME SDK location

Your local.properties file might be missing. If so add a file named 'local.properties' inside /local.properties and provide the sdk location as following.

sdk.dir=C:\Users\\AppData\Local\Android\Sdk

How to get all the AD groups for a particular user?

You should use System.DirectoryServices.AccountManagement. It's much easier. Here is a nice code project article giving you an overview on all the classes in this DLL.

As you pointed out, your current approach doesn't find out the primary group. Actually, it's much worse than you thought. There are some more cases that it doesn't work, like the domain local group from another domain. You can check here for details. Here is how the code looks like if you switch to use System.DirectoryServices.AccountManagement. The following code can find the immediate groups this user assigned to, which includes the primary group.

UserPrincipal user = UserPrincipal.FindByIdentity(new PrincipalContext (ContextType.Domain, "mydomain.com"), IdentityType.SamAccountName, "username");
foreach (GroupPrincipal group in user.GetGroups())
{
    Console.Out.WriteLine(group);
}

Retrieving Property name from lambda expression

I leave this function if you want to get multiples fields:

/// <summary>
    /// Get properties separated by , (Ex: to invoke 'd => new { d.FirstName, d.LastName }')
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="exp"></param>
    /// <returns></returns>
    public static string GetFields<T>(Expression<Func<T, object>> exp)
    {
        MemberExpression body = exp.Body as MemberExpression;
        var fields = new List<string>();
        if (body == null)
        {
            NewExpression ubody = exp.Body as NewExpression;
            if (ubody != null)
                foreach (var arg in ubody.Arguments)
                {
                    fields.Add((arg as MemberExpression).Member.Name);
                }
        }

        return string.Join(",", fields);
    }

How to Read and Write from the Serial Port

Note that usage of a SerialPort.DataReceived event is optional. You can set proper timeout using SerialPort.ReadTimeout and continuously call SerialPort.Read() after you wrote something to a port until you get a full response.

Moreover you can use SerialPort.BaseStream property to extract an underlying Stream instance. The benefit of using a Stream is that you can easily utilize various decorators with it:

var port = new SerialPort();
// LoggingStream inherits Stream, implements IDisposable, needen abstract methods and 
// overrides needen virtual methods. 
Stream portStream = new LoggingStream(port.BaseStream);
portStream.Write(...); // Logs write buffer.
portStream.Read(...); // Logs read buffer.

For more information check:

Top 5 SerialPort Tips article by Kim Hamilton, BCL Team Blog
C# await event and timeout in serial port communication discussion on StackOverflow

Deleting Objects in JavaScript

Setting a variable to null makes sure to break any references to objects in all browsers including circular references being made between the DOM elements and Javascript scopes. By using delete command we are marking objects to be cleared on the next run of the Garbage collection, but if there are multiple variables referencing the same object, deleting a single variable WILL NOT free the object, it will just remove the linkage between that variable and the object. And on the next run of the Garbage collection, only the variable will be cleaned.

Automated way to convert XML files to SQL database?

For Mysql please see the LOAD XML Syntax^Docs.

It should work without any additional XML transformation for the XML you've provided, just specify the format and define the table inside the database firsthand with matching column names:

LOAD XML LOCAL INFILE 'table1.xml'
    INTO TABLE table1
    ROWS IDENTIFIED BY '<table1>';

There is also a related question:

How to import XMl file into MySQL database table using XML_LOAD(); function

For Postgresql I do not know.

How to read a configuration file in Java

It depends.

Start with Basic I/O, take a look at Properties, take a look at Preferences API and maybe even Java API for XML Processing and Java Architecture for XML Binding

And if none of those meet your particular needs, you could even look at using some kind of Database

cannot connect to pc-name\SQLEXPRESS

My issue occurs when I add a PC to a domain. Restarting the service, making sure it's running, that it has the correct credentials to run, etc, as in other answers doesn't work. I don't know exactly what the problem is, but I can't even log in with the local user anymore to give the domain user access. Here's the steps that work for me:

In SSMS

View > Registered Servers
Database Engine > Local Server Groups > right-click pcname\sqlexpress
Delete > Yes
Right-click Local Server Groups > Tasks > Register Local Servers
It confirms that it re-registered. pcname\sqlexpress reappears.

I'm then able to log in with the local windows auth'd user again, my databases are all there and everything. I then go about my business adding the domain user to Security > Logins.

How to use an environment variable inside a quoted string in Bash

Just a quick note/summary for any who came here via Google looking for the answer to the general question asked in the title (as I was). Any of the following should work for getting access to shell variables inside quotes:

echo "$VARIABLE"
echo "${VARIABLE}"

Use of single quotes is the main issue. According to the Bash Reference Manual:

Enclosing characters in single quotes (') preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash. [...] Enclosing characters in double quotes (") preserves the literal value of all characters within the quotes, with the exception of $, `, \, and, when history expansion is enabled, !. The characters $ and ` retain their special meaning within double quotes (see Shell Expansions). The backslash retains its special meaning only when followed by one of the following characters: $, `, ", \, or newline. Within double quotes, backslashes that are followed by one of these characters are removed. Backslashes preceding characters without a special meaning are left unmodified. A double quote may be quoted within double quotes by preceding it with a backslash. If enabled, history expansion will be performed unless an ! appearing in double quotes is escaped using a backslash. The backslash preceding the ! is not removed. The special parameters * and @ have special meaning when in double quotes (see Shell Parameter Expansion).

In the specific case asked in the question, $COLUMNS is a special variable which has nonstandard properties (see lhunath's answer above).

How to checkout a specific Subversion revision from the command line?

If you already have it checked out locally then you can cd to where it is checked out, then use this syntax:

$ svn up -rXXXX

ref: Checkout a specific revision from subversion from command line

How does internationalization work in JavaScript?

Localization support in legacy browsers is poor. Originally, this was due to phrases in the ECMAScript language spec that look like this:

Number.prototype.toLocaleString()
Produces a string value that represents the value of the Number formatted according to the conventions of the host environment’s current locale. This function is implementation-dependent, and it is permissible, but not encouraged, for it to return the same thing as toString.

Every localization method defined in the spec is defined as "implementation-dependent", which results in a lot of inconsistencies. In this instance, Chrome Opera and Safari would return the same thing as .toString(). Firefox and IE will return locale formatted strings, and IE even includes a thousand separator (perfect for currency strings). Chrome was recently updated to return a thousands-separated string, though with no fixed decimal.

For modern environments, the ECMAScript Internationalization API spec, a new standard that complements the ECMAScript Language spec, provides much better support for string comparison, number formatting, and the date and time formatting; it also fixes the corresponding functions in the Language Spec. An introduction can be found here. Implementations are available in:

Chrome 24
Firefox 29
Internet Explorer 11
Opera 15

There is also a compatibility implementation, Intl.js, which will provide the API in environments where it doesn't already exist.

Determining the user's preferred language remains a problem since there's no specification for obtaining the current language. Each browser implements a method to obtain a language string, but this could be based on the user's operating system language or just the language of the browser:

// navigator.userLanguage for IE, navigator.language for others
var lang = navigator.language || navigator.userLanguage;

A good workaround for this is to dump the Accept-Language header from the server to the client. If formatted as a JavaScript, it can be passed to the Internationalization API constructors, which will automatically pick the best (or first-supported) locale.

In short, you have to put in a lot of the work yourself, or use a framework/library, because you cannot rely on the browser to do it for you.

Various libraries and plugins for localization:

Mantained by an open community (no order):

Polyglot.js - AirBnb's internationalization library
Intl.js - a compatibility implementation of the Internationalisation API
i18next (home) for i18n (incl. jquery plugin, translation ui,...)
moment.js (home) for dates
numbro.js (home) (was numeral.js (home)) for numbers and currency
l10n.js (home)
L10ns (home) tool for i18n workflow and complex string formatting
jQuery Localisation (plugin) (home)
YUI Internationalization support
jquery.i18Now for dates
browser-i18n with support to pluralization
counterpart is inspired by Ruby's famous I18n gem
jQuery Globalize jQuery's own i18n library
js-lingui - MessageFormat implementation for JS (ES2016) and React

Others:

jQuery Globalization (plugin)
requirejs-i18n Define an I18N Bundle with RequireJS.

Feel free to add/edit.

How to write one new line in Bitbucket markdown?

It's possible, as addressed in Issue #7396:

When you do want to insert a <br /> break tag using Markdown, you end a line with two or more spaces, then type return or Enter.

Regular Expression to match only alphabetic characters

In Ruby and other languages that support POSIX character classes in bracket expressions, you can do simply:

/\A[[:alpha:]]+\z/i

That will match alpha-chars in all Unicode alphabet languages. Easy peasy.

More info: http://en.wikipedia.org/wiki/Regular_expression#Character_classes http://ruby-doc.org/core-2.0/Regexp.html

ReactJS Two components communicating

I saw that the question is already answered, but if you'd like to learn more details, there are a total of 3 cases of communication between components:

Case 1: Parent to Child communication
Case 2: Child to Parent communication
Case 3: Not-related components (any component to any component) communication

Validate phone number using angular js

use ng-intl-tel-input to validate mobile numbers for all countries. you can set default country also. on npm: https://www.npmjs.com/package/ng-intl-tel-input

more details: https://techpituwa.wordpress.com/2017/03/29/angular-js-phone-number-validation-with-ng-intl-tel-input/

Programs & Examples On #Minimum spanning tree

When should I use Kruskal as opposed to Prim (and vice versa)?

Language Books/Tutorials for popular languages

Check for null variable in Windows batch

How can I change the font-size of a select option?

Getter and Setter?

Numpy: Creating a complex array from 2 real ones?

How do you specify the Java compiler version in a pom.xml file?

How do I use FileSystemObject in VBA?

How to display databases in Oracle 11g using SQL*Plus

HTML button onclick event

Input type "number" won't resize

Decoding UTF-8 strings in Python

Sizing elements to percentage of screen width/height

In C#, how to check if a TCP port is available?

Angular2 material dialog has issues - Did you add it to @NgModule.entryComponents?

SQL query: Delete all records from the table except latest N?

How to exclude *AutoConfiguration classes in Spring Boot JUnit tests?

Stacked bar chart

How to import existing *.sql files in PostgreSQL 8.4?

UTF-8 in Windows 7 CMD

Convert interface{} to int

How do I make a fully statically linked .exe with Visual Studio Express 2005?

How can I undo a mysql statement that I just executed?

Node.js: Python not found exception due to node-sass and node-gyp

How to list active / open connections in Oracle?

WHERE vs HAVING

What data is stored in Ephemeral Storage of Amazon EC2 instance?

Tomcat: LifecycleException when deploying

Filtering DataSet

String array initialization in Java

php search array key and get value

How is the AND/OR operator represented as in Regular Expressions?

Detect if a Form Control option button is selected in VBA

What is the difference between utf8mb4 and utf8 charsets in MySQL?

Remove file extension from a file name string

JavaScript console.log causes error: "Synchronous XMLHttpRequest on the main thread is deprecated..."

AngularJS: ng-model not binding to ng-checked for checkboxes

Notepad++ Setting for Disabling Auto-open Previous Files

What does "The code generator has deoptimised the styling of [some file] as it exceeds the max of "100KB"" mean?

Perl: function to trim string leading and trailing whitespace

How to extract duration time from ffmpeg output?

How can I open Windows Explorer to a certain directory from within a WPF app?

Dark color scheme for Eclipse

How to retrieve the current version of a MySQL database management system (DBMS)?

JavaScript get element by name

state provider and route provider in angularJS

Select random element in a list of R?

What does the 'export' command do?

Is there a simple way to remove multiple spaces in a string?

What are major differences between C# and Java?

XPath to return only elements containing the text, and not its parents

How can I detect window size with jQuery?

Bootstrap 3.0 Popovers and tooltips

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

Differences between TCP sockets and web sockets, one more time

How to Parse a JSON Object In Android

Does Notepad++ show all hidden characters?

Is it safe to store a JWT in localStorage with ReactJS?

Use a JSON array with objects with javascript

Error:Conflict with dependency 'com.google.code.findbugs:jsr305'

1st

2nd

3rd

How to reload/refresh an element(image) in jQuery

How to solve a timeout error in Laravel 5

How do I render a shadow?

How to fill a Javascript object literal with many static key/value pairs efficiently?

iOS9 getting error “an SSL error has occurred and a secure connection to the server cannot be made”

How to create enum like type in TypeScript?

How do I import a .dmp file into Oracle?

How to get a substring of text?

Error: Node Sass version 5.0.0 is incompatible with ^4.0.0

PostgreSQL psql terminal command

Using jquery to delete all elements with a given id

SQLite Query in Android to count rows

Regex empty string or email

Passing additional variables from command line to make

Autocompletion of @author in Intellij

Merge some list items in a Python List