Programs & Examples On #Framework caching

How to launch Safari and open URL from iOS app

In SWIFT 3.0

               if let url = URL(string: "https://www.google.com") {
                 UIApplication.shared.open(url, options: [:])
               }

SessionNotCreatedException: Message: session not created: This version of ChromeDriver only supports Chrome version 81

Do below steps :

  1. Check the version of chrome browser.

  2. download chromedriver of same version from https://sites.google.com/a/chromium.org/chromedriver/

  3. Give correct path in the pycharm and run the code.

Deserialize JSON with C#

Serialization:

// Convert an object to JSON string format
string jsonData = JsonConvert.SerializeObject(obj);

Response.Write(jsonData);

Deserialization::

To deserialize a dynamic object

  string json = @"{
      'Name': 'name',
      'Description': 'des'
    }";

var res = JsonConvert.DeserializeObject< dynamic>(json);

Response.Write(res.Name);

How to extract 1 screenshot for a video with ffmpeg at a given time?

FFMpeg can do this by seeking to the given timestamp and extracting exactly one frame as an image, see for instance:

ffmpeg -i input_file.mp4 -ss 01:23:45 -vframes 1 output.jpg

Let's explain the options:

-i input file           the path to the input file
-ss 01:23:45            seek the position to the specified timestamp
-vframes 1              only handle one video frame
output.jpg              output filename, should have a well-known extension

The -ss parameter accepts a value in the form HH:MM:SS[.xxx] or as a number in seconds. If you need a percentage, you need to compute the video duration beforehand.

Is it possible to change the location of packages for NuGet?

  1. Created a file called "nuget.config".
  2. Added that file to my solutions folder

this did NOT work for me:

<configuration>
  <config>
    <add key="repositoryPath" value="..\ExtLibs\Packages" />
  </config>
  ... 
</configuration>

this did WORK for me:

<?xml version="1.0" encoding="utf-8"?>
<settings>
  <repositoryPath>..\ExtLibs\Packages</repositoryPath>
</settings>

What is Bootstrap?

Bootstrap is the world’s most popular and widely used open-source framework for developing with HTML, CSS, and JS. It is a front end framework of HTML. Bootstrap helps in building responsive websites or web applications and a 12-column grid system that helps dynamically adjust the website to a suitable screen resolution. The current version of bootstrap is 4.3.1 and the bootstrap team has also officially announced Bootstrap 5 version and changes like removing jquery from bootstrap. Some of the crucial reasons why bootstrap framework is most preferable are

  • It is easy to use

  • Bootstrap has a big community support

  • Customizations can be done easily

  • It increases development speed

  • Responsiveness

    For more details, you can check the official website: https://getbootstrap.com/

Source: https://vmokshagroup.com/blog/bootstrap-advantages/

Callback functions in C++

Boost's signals2 allows you to subscribe generic member functions (without templates!) and in a threadsafe way.

Example: Document-View Signals can be used to implement flexible Document-View architectures. The document will contain a signal to which each of the views can connect. The following Document class defines a simple text document that supports mulitple views. Note that it stores a single signal to which all of the views will be connected.

class Document
{
public:
    typedef boost::signals2::signal<void ()>  signal_t;

public:
    Document()
    {}

    /* Connect a slot to the signal which will be emitted whenever
      text is appended to the document. */
    boost::signals2::connection connect(const signal_t::slot_type &subscriber)
    {
        return m_sig.connect(subscriber);
    }

    void append(const char* s)
    {
        m_text += s;
        m_sig();
    }

    const std::string& getText() const
    {
        return m_text;
    }

private:
    signal_t    m_sig;
    std::string m_text;
};

Next, we can begin to define views. The following TextView class provides a simple view of the document text.

class TextView
{
public:
    TextView(Document& doc): m_document(doc)
    {
        m_connection = m_document.connect(boost::bind(&TextView::refresh, this));
    }

    ~TextView()
    {
        m_connection.disconnect();
    }

    void refresh() const
    {
        std::cout << "TextView: " << m_document.getText() << std::endl;
    }
private:
    Document&               m_document;
    boost::signals2::connection  m_connection;
};

EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0) on dispatch_semaphore_dispose

I landed here because of an XCTestCase, in which I'd disabled most of the tests by prefixing them with 'no_' as in no_testBackgroundAdding. Once I noticed that most of the answers had something to do with locks and threading, I realized the test contained a few instances of XCTestExpectation with corresponding waitForExpectations. They were all in the disabled tests, but apparently Xcode was still evaluating them at some level.

In the end I found an XCTestExpectation that was defined as @property but lacked the @synthesize. Once I added the synthesize directive, the EXC_BAD_INSTRUCTION disappeared.

Is quitting an application frowned upon?

Almost 99% of the time there is no need for an Android application to take over its own life cycle. Most of the time it comes down to better planning or smarter design of the application. For example, rather build an internal service (not exported) to handle downloads, etc., or design actions and tasks around user workflow.

But that being said, where there is a will there is a way. Android provides - through the android.os.Process class, a much better API than Java to control the underlying process. And unlike Java it does not treat the developer like a moron by hiding it all behind a simple java.lang.System.exit() call.

So how do you ask your application to commit suicide in Android? Well, the trick is simple:

Create your own Android application class by inheriting from the standard android.app.Application class (remember to declare it in the AndroidManifest.xml file).

Override the onCreate() method, and store the process ID which started your application:

this.pid = android.os.Process.myPid(); // Save for later use.

Now to kill your application, provide a kill() method:

android.os.Process.sendSignal(pid, android.os.Process.SIGNAL_KILL);

Now whenever you need your app to commit suicide just type cast the application context, and call your kill method!

((MySuicidalApp) context.getApplicationContext()).kill()

Just remember that due to the process management policies in Android, specifically related to services, Android may just opt to restart your service (see You should not use task killers on Android).

Example using Hyperlink in WPF

If you want your application to open the link in a web browser you need to add a HyperLink with the RequestNavigate event set to a function that programmatically opens a web-browser with the address as a parameter.

<TextBlock>           
    <Hyperlink NavigateUri="http://www.google.com" RequestNavigate="Hyperlink_RequestNavigate">
        Click here
    </Hyperlink>
</TextBlock>

In the code-behind you would need to add something similar to this to handle the RequestNavigate event:

private void Hyperlink_RequestNavigate(object sender, RequestNavigateEventArgs e)
{
    // for .NET Core you need to add UseShellExecute = true
    // see https://docs.microsoft.com/dotnet/api/system.diagnostics.processstartinfo.useshellexecute#property-value
    Process.Start(new ProcessStartInfo(e.Uri.AbsoluteUri));
    e.Handled = true;
}

In addition you will also need the following imports:

using System.Diagnostics;
using System.Windows.Navigation;

It will look like this in your application:

oO

Where can I find the Java SDK in Linux after installing it?

This depends a bit from your package system ... if the java command works, you can type readlink -f $(which java) to find the location of the java command. On the OpenSUSE system I'm on now it returns /usr/lib64/jvm/java-1.6.0-openjdk-1.6.0/jre/bin/java (but this is not a system which uses apt-get).


On Ubuntu, it looks like it is in /usr/lib/jvm/java-6-openjdk/ for OpenJDK, and in some other subdirectory of /usr/lib/jvm/ for Suns JDK (and other implementations as well, I think).

Debian is the same.


For any given package you can determine what files it installs and where it installs them by querying dpkg. For example for the package 'openjdk-6-jdk': dpkg -L openjdk-6-jdk

HTML select drop-down with an input field

You can use input text with "list" attribute, which refers to the datalist of values.

_x000D_
_x000D_
<input type="text" name="city" list="cityname">_x000D_
    <datalist id="cityname">_x000D_
      <option value="Boston">_x000D_
      <option value="Cambridge">_x000D_
    </datalist>
_x000D_
_x000D_
_x000D_

This creates a free text input field that also has a drop-down to select predefined choices. Attribution for example and more information: https://www.w3.org/wiki/HTML/Elements/datalist

Android: remove left margin from actionbar's custom layout

If you are adding the Toolbar via XML, you can simply add XML attributes to remove content insets.

<android.support.v7.widget.Toolbar
    xmlns:app="schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/primaryColor"
    android:contentInsetLeft="0dp"
    android:contentInsetStart="0dp"
    app:contentInsetLeft="0dp"
    app:contentInsetStart="0dp"
    android:contentInsetRight="0dp"
    android:contentInsetEnd="0dp"
    app:contentInsetRight="0dp"
    app:contentInsetEnd="0dp" />

Stop a youtube video with jquery?

I was facing the same problem. After a lot of alternatives what I did was just reset the embed src="" with the same URL.

Code snippet:

  $("#videocontainer").fadeOut(200);<br/>
  $("#videoplayer").attr("src",videoURL);

I was able to at least stop the video from playing when I hide it.:-)

How can I get the current stack trace in Java?

For people, who just want to get the current stacktrace to their logs, I would go with:

getLogger().debug("Message", new Throwable());

Cheers

WHERE clause on SQL Server "Text" data type

That is not what the error message says. It says that you cannot use the = operator. Try for instance LIKE 'foo'.

Python: can't assign to literal

Just adding 1 more scenario which may give the same error:

If you try to assign values to multiple variables, then also you will receive same error. For e.g.

In C (and many other languages), this is possible:

int a=2, b=3;

In Python:

a=2, b=5

will give error:

can't assign to literal

EDIT:

As per Arne's comment below, you can do this in Python for single line assignments in a slightly different way: a, b = 2, 5

C split a char array into different variables

In addition, you can use sscanf for some very simple scenarios, for example when you know exactly how many parts the string has and what it consists of. You can also parse the arguments on the fly. Do not use it for user inputs because the function will not report conversion errors.

Example:

char text[] = "1:22:300:4444:-5";
int i1, i2, i3, i4, i5;
sscanf(text, "%d:%d:%d:%d:%d", &i1, &i2, &i3, &i4, &i5);
printf("%d, %d, %d, %d, %d", i1, i2, i3, i4, i5);

Output:

1, 22, 300, 4444, -5

For anything more advanced, strtok() and strtok_r() are your best options, as mentioned in other answers.

Updating a dataframe column in spark

Just as maasg says you can create a new DataFrame from the result of a map applied to the old DataFrame. An example for a given DataFrame df with two rows:

val newDf = sqlContext.createDataFrame(df.map(row => 
  Row(row.getInt(0) + SOMETHING, applySomeDef(row.getAs[Double]("y")), df.schema)

Note that if the types of the columns change, you need to give it a correct schema instead of df.schema. Check out the api of org.apache.spark.sql.Row for available methods: https://spark.apache.org/docs/latest/api/java/org/apache/spark/sql/Row.html

[Update] Or using UDFs in Scala:

import org.apache.spark.sql.functions._

val toLong = udf[Long, String] (_.toLong)

val modifiedDf = df.withColumn("modifiedColumnName", toLong(df("columnName"))).drop("columnName")

and if the column name needs to stay the same you can rename it back:

modifiedDf.withColumnRenamed("modifiedColumnName", "columnName")

How to print table using Javascript?

My fellows,

In January 2019 I used a code made before:

 <script type="text/javascript">   
    function imprimir() {
        var divToPrint=document.getElementById("ConsutaBPM");
        newWin= window.open("");
        newWin.document.write(divToPrint.outerHTML);
        newWin.print();
        newWin.close();
    }
</script>

To undestand: ConsutaBPM is a DIV which contains inside phrases and tables. I wanted to print ALL, titles, table, and others. The problem was when TRIED to print the TABLE...

The table mas be defined with BORDER and CELLPADDING:

<table border='1' cellpadding='1' id='Tablbpm1' >

It worked fine!!!

Casting a number to a string in TypeScript

One can also use the following syntax in typescript. Note the backtick " ` "

window.location.hash = `${page_number}`

If/else else if in Jquery for a condition

Change the less-than operator to a greater-than-or-equal-to operator:

}elseif($("#seats").val() >= 99999){

How can I commit a single file using SVN over a network?

this should work:

svn commit -m "<Your message here>" path/to/your/file

you can also add multiple files like this:

svn commit -m "<Your message here>" path/to/your/file [path/to/your/file] [path/to/your/file]

Update query PHP MySQL

Update a row or column of a table

$update = "UPDATE daily_patients SET queue_status = 'pending' WHERE doctor_id = $room_no and serial_number= $serial_num";

if ($con->query($update) === TRUE) {
    echo "Record updated successfully";
} else {
    echo "Error updating record: " . $con->error;
}

What are the differences between a superkey and a candidate key?

In nutshell: CANDIDATE KEY is a minimal SUPER KEY.

Where Super key is the combination of columns(or attributes) that uniquely identify any record(or tuple) in a relation(table) in RDBMS.


For instance, consider the following dependencies in a table having columns A, B, C, and D (Giving this table just for a quick example so not covering all dependencies that R could have).

Attribute set (Determinant)---Can Identify--->(Dependent)

A-----> AD

B-----> ABCD

C-----> CD

AC----->ACD

AB----->ABCD

ABC----->ABCD

BCD----->ABCD


Now, B, AB, ABC, BCD identifies all columns so those four qualify for the super key.

But, B?AB; B?ABC; B?BCD hence AB, ABC, and BCD disqualified for CANDIDATE KEY as their subsets could identify the relation, so they aren't minimal and hence only B is the candidate key, not the others.

One more thing Primary key is any one among the candidate keys.

Thanks for asking

Gets last digit of a number

Another interesting way to do it which would also allow more than just the last number to be taken would be:

int number = 124454;
int overflow = (int)Math.floor(number/(1*10^n))*10^n;

int firstDigits = number - overflow;
//Where n is the number of numbers you wish to conserve</code>

In the above example if n was 1 then the program would return: 4

If n was 3 then the program would return 454

When to use single quotes, double quotes, and backticks in MySQL

Backticks are to be used for table and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommended to avoid using reserved keywords as column or table identifiers when possible, avoiding the quoting issue.

Single quotes should be used for string values like in the VALUES() list. Double quotes are supported by MySQL for string values as well, but single quotes are more widely accepted by other RDBMS, so it is a good habit to use single quotes instead of double.

MySQL also expects DATE and DATETIME literal values to be single-quoted as strings like '2001-01-01 00:00:00'. Consult the Date and Time Literals documentation for more details, in particular alternatives to using the hyphen - as a segment delimiter in date strings.

So using your example, I would double-quote the PHP string and use single quotes on the values 'val1', 'val2'. NULL is a MySQL keyword, and a special (non)-value, and is therefore unquoted.

None of these table or column identifiers are reserved words or make use of characters requiring quoting, but I've quoted them anyway with backticks (more on this later...).

Functions native to the RDBMS (for example, NOW() in MySQL) should not be quoted, although their arguments are subject to the same string or identifier quoting rules already mentioned.

Backtick (`)
table & column ------------------------------------------------------+
                      ?     ?  ?  ?  ?    ?  ?    ?  ?    ?  ?       ?
$query = "INSERT INTO `table` (`id`, `col1`, `col2`, `date`, `updated`) 
                       VALUES (NULL, 'val1', 'val2', '2001-01-01', NOW())";
                               ????  ?    ?  ?    ?  ?          ?  ????? 
Unquoted keyword          --------+  ¦    ¦  ¦    ¦  ¦          ¦  ¦¦¦¦¦
Single-quoted (') strings ------------------------+  ¦          ¦  ¦¦¦¦¦
Single-quoted (') DATE    --------------------------------------+  ¦¦¦¦¦
Unquoted function         ---------------------------------------------+    

Variable interpolation

The quoting patterns for variables do not change, although if you intend to interpolate the variables directly in a string, it must be double-quoted in PHP. Just make sure that you have properly escaped the variables for use in SQL. (It is recommended to use an API supporting prepared statements instead, as protection against SQL injection).

// Same thing with some variable replacements
// Here, a variable table name $table is backtick-quoted, and variables
// in the VALUES list are single-quoted 
$query = "INSERT INTO `$table` (`id`, `col1`, `col2`, `date`) VALUES (NULL, '$val1', '$val2', '$date')";

Prepared statements

When working with prepared statements, consult the documentation to determine whether or not the statement's placeholders must be quoted. The most popular APIs available in PHP, PDO and MySQLi, expect unquoted placeholders, as do most prepared statement APIs in other languages:

// PDO example with named parameters, unquoted
$query = "INSERT INTO `table` (`id`, `col1`, `col2`, `date`) VALUES (:id, :col1, :col2, :date)";

// MySQLi example with ? parameters, unquoted
$query = "INSERT INTO `table` (`id`, `col1`, `col2`, `date`) VALUES (?, ?, ?, ?)";

Characters requring backtick quoting in identifiers:

According to MySQL documentation, you do not need to quote (backtick) identifiers using the following character set:

ASCII: [0-9,a-z,A-Z$_] (basic Latin letters, digits 0-9, dollar, underscore)

You can use characters beyond that set as table or column identifiers, including whitespace for example, but then you must quote (backtick) them.

Also, although numbers are valid characters for identifiers, identifiers cannot consist solely of numbers. If they do they must be wrapped in backticks.

How to detect the character encoding of a text file?

Use StreamReader and direct it to detect the encoding for you:

using (var reader = new System.IO.StreamReader(path, true))
{
    var currentEncoding = reader.CurrentEncoding;
}

And use Code Page Identifiers https://msdn.microsoft.com/en-us/library/windows/desktop/dd317756(v=vs.85).aspx in order to switch logic depending on it.

Filter by process/PID in Wireshark

On Windows there is an experimental build that does this, as described on the mailing list, Filter by local process name

ECONNREFUSED error when connecting to mongodb from node.js

I had facing the same issue while writing a simple rest api using node.js eventually found out it was due to wifi blockage and security reason . try once connecting it using your mobile hotspot . if this be the reason it will get resolved immediately.

How to vertically center a container in Bootstrap?

Give the container class

.container{
    height: 100vh;
    width: 100vw;
    display: flex;
}

Give the div that's inside the container:

align-content: center;

All the content inside this div will show up in the middle of the page.

Finding sum of elements in Swift array

this is my approach about this. however I believe that the best solution is the answer from the user username tbd

var i = 0 
var sum = 0
let example = 0
for elements in multiples{
    i = i + 1
    sum = multiples[ (i- 1)]
    example = sum + example
}

Unable to start the mysql server in ubuntu

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

  • mysql is client
  • mysqld is the server

Try: sudo service mysqld start

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

Uninstalling:

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

Re-Installing:

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

Backup entire folder before doing this:

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

AngularJS app.run() documentation?

Specifically...

How and where is app.run() used? After module definition or after app.config(), after app.controller()?

Where:

In your package.js E.g. /packages/dashboard/public/controllers/dashboard.js

How:

Make it look like this

var app = angular.module('mean.dashboard', ['ui.bootstrap']);

app.controller('DashboardController', ['$scope', 'Global', 'Dashboard',
    function($scope, Global, Dashboard) {
        $scope.global = Global;
        $scope.package = {
            name: 'dashboard'
        };
        // ...
    }
]);

app.run(function(editableOptions) {
    editableOptions.theme = 'bs3'; // bootstrap3 theme. Can be also 'bs2', 'default'
});

How to create a property for a List<T>

You could do this but the T generic parameter needs to be declared at the containing class:

public class Foo<T>
{
    public List<T> NewList { get; set; }
}

How do I compute derivative using Numpy?

You have four options

  1. Finite Differences
  2. Automatic Derivatives
  3. Symbolic Differentiation
  4. Compute derivatives by hand.

Finite differences require no external tools but are prone to numerical error and, if you're in a multivariate situation, can take a while.

Symbolic differentiation is ideal if your problem is simple enough. Symbolic methods are getting quite robust these days. SymPy is an excellent project for this that integrates well with NumPy. Look at the autowrap or lambdify functions or check out Jensen's blogpost about a similar question.

Automatic derivatives are very cool, aren't prone to numeric errors, but do require some additional libraries (google for this, there are a few good options). This is the most robust but also the most sophisticated/difficult to set up choice. If you're fine restricting yourself to numpy syntax then Theano might be a good choice.

Here is an example using SymPy

In [1]: from sympy import *
In [2]: import numpy as np
In [3]: x = Symbol('x')
In [4]: y = x**2 + 1
In [5]: yprime = y.diff(x)
In [6]: yprime
Out[6]: 2·x

In [7]: f = lambdify(x, yprime, 'numpy')
In [8]: f(np.ones(5))
Out[8]: [ 2.  2.  2.  2.  2.]

How to add a linked source folder in Android Studio?

If you're not using gradle (creating a project from an APK, for instance), this can be done through the Android Studio UI (as of version 3.3.2):

  • Right-click the project root directory, pick Open Module Settings
  • Hit the + Add Content Root button (center right)
  • Add your path and hit OK

In my experience (with native code), as long as your .so's are built with debug symbols and from the same absolute paths, breakpoints added in source files will be automatically recognized.

require_once :failed to open stream: no such file or directory

It says that the file C:\wamp\www\mysite\php\includes\dbconn.inc doesn't exist, so the error is, you're missing the file.

How can I build XML in C#?

For simple things, I just use the XmlDocument/XmlNode/XmlAttribute classes and XmlDocument DOM found in System.XML.

It generates the XML for me, I just need to link a few items together.

However, on larger things, I use XML serialization.

Change the background color in a twitter bootstrap modal?

Add the following CSS;

.modal .modal-dialog .modal-content{  background-color: #d4c484; }

<div class="modal fade">
<div class="modal-dialog" role="document">
<div class="modal-content">
...
...

Android Studio not showing modules in project structure

Had similar issue when running version control on a project in Android Studio (0.4.2). When pulling it down to a new location and importing the modules, only the "Android SDK" were showing in the Project Structure.

I removed the .idea/ folder from the version control, by adding it to .gitignore file, and did a fresh pull and imported the modules. Now all the settings appeared correctly in the Project Settings and Platform Settings for the Project Structure.

Undo a particular commit in Git that's been pushed to remote repos

Because it has already been pushed, you shouldn't directly manipulate history. git revert will revert specific changes from a commit using a new commit, so as to not manipulate commit history.

How to print matched regex pattern using awk?

gawk can get the matching part of every line using this as action:

{ if (match($0,/your regexp/,m)) print m[0] }

match(string, regexp [, array]) If array is present, it is cleared, and then the zeroth element of array is set to the entire portion of string matched by regexp. If regexp contains parentheses, the integer-indexed elements of array are set to contain the portion of string matching the corresponding parenthesized subexpression. http://www.gnu.org/software/gawk/manual/gawk.html#String-Functions

Installing Google Protocol Buffers on mac

It's a new year and there's a new mismatch between the version of protobuf in Homebrew and the cutting edge release. As of February 2016, brew install protobuf will give you version 2.6.1.

If you want the 3.0 beta release instead, you can install it with:

brew install --devel protobuf

What is the difference between a framework and a library?

I think library is a set of utilities to reach a goal (for example, sockets, cryptography, etc). Framework is library + RUNTIME EINVIRONNEMENT. For example, ASP.NET is a framework: it accepts HTTP requests, create page object, invoke lyfe cicle events, etc. Framework does all this, you write a bit of code which will be run at a specific time of the life cycle of current request!

Anyway, very interestering question!

How to convert a "dd/mm/yyyy" string to datetime in SQL Server?

SELECT convert(varchar(10), '23/07/2009', 111)

How to get element-wise matrix multiplication (Hadamard product) in numpy?

For elementwise multiplication of matrix objects, you can use numpy.multiply:

import numpy as np
a = np.array([[1,2],[3,4]])
b = np.array([[5,6],[7,8]])
np.multiply(a,b)

Result

array([[ 5, 12],
       [21, 32]])

However, you should really use array instead of matrix. matrix objects have all sorts of horrible incompatibilities with regular ndarrays. With ndarrays, you can just use * for elementwise multiplication:

a * b

If you're on Python 3.5+, you don't even lose the ability to perform matrix multiplication with an operator, because @ does matrix multiplication now:

a @ b  # matrix multiplication

Add days Oracle SQL

If you want to add N days to your days. You can use the plus operator as follows -

SELECT ( SYSDATE + N ) FROM DUAL;

How do I output the results of a HiveQL query to CSV?

In case you are doing it from Windows you can use Python script hivehoney to extract table data to local CSV file.

It will:

  1. Login to bastion host.
  2. pbrun.
  3. kinit.
  4. beeline (with your query).
  5. Save echo from beeline to a file on Windows.

Execute it like this:

set PROXY_HOST=your_bastion_host

set SERVICE_USER=you_func_user

set LINUX_USER=your_SOID

set LINUX_PWD=your_pwd

python hh.py --query_file=query.sql

typeof operator in C

It is a C extension from the GCC compiler , see http://gcc.gnu.org/onlinedocs/gcc/Typeof.html

How/when to use ng-click to call a route?

You can use:

<a ng-href="#/about">About</a>

If you want some dynamic variable inside href you can do like this way:

<a ng-href="{{link + 123}}">Link to 123</a>

Where link is Angular scope variable.

What USB driver should we use for the Nexus 5?

My Nexus 5 is identyfied by the id = USB\VID_18D1&PID_D001.

Use the Google USB drivers, and modify file android_winusb.inf. Find the lines:

;Google Nexus (generic)
%SingleBootLoaderInterface% = USB_Install, USB\VID_18D1&PID_4EE0

And add below:

%CompositeAdbInterface%     = USB_Install, USB\VID_18D1&PID_D001

Repeat it, because there are two sections to modify, [Google.NTx86] and [Google.NTamd64].

If you continue with problems, try this:

Connect your Nexus 5, go to Device Manager, find the Nexus 5 on "other" and right click. Select properties, details, and in selection list, and select hardware id. Write down the short ID, and modify the line with:

%CompositeAdbInterface% = USB_Install, YOUR_SHORT_ID

Function to calculate distance between two coordinates

I implemeneted this algorithm in typescript and ES6

export type Coordinate = {
  lat: number;
  lon: number;
};

get the distance between two points:

function getDistanceBetweenTwoPoints(cord1: Coordinate, cord2: Coordinate) {
  if (cord1.lat == cord2.lat && cord1.lon == cord2.lon) {
    return 0;
  }

  const radlat1 = (Math.PI * cord1.lat) / 180;
  const radlat2 = (Math.PI * cord2.lat) / 180;

  const theta = cord1.lon - cord2.lon;
  const radtheta = (Math.PI * theta) / 180;

  let dist =
    Math.sin(radlat1) * Math.sin(radlat2) +
    Math.cos(radlat1) * Math.cos(radlat2) * Math.cos(radtheta);

  if (dist > 1) {
    dist = 1;
  }

  dist = Math.acos(dist);
  dist = (dist * 180) / Math.PI;
  dist = dist * 60 * 1.1515;
  dist = dist * 1.609344; //convert miles to km
  
  return dist;
}

get the distance between an array of coordinates

export function getTotalDistance(coordinates: Coordinate[]) {
  coordinates = coordinates.filter((cord) => {
    if (cord.lat && cord.lon) {
      return true;
    }
  });
  
  let totalDistance = 0;

  if (!coordinates) {
    return 0;
  }

  if (coordinates.length < 2) {
    return 0;
  }

  for (let i = 0; i < coordinates.length - 2; i++) {
    if (
      !coordinates[i].lon ||
      !coordinates[i].lat ||
      !coordinates[i + 1].lon ||
      !coordinates[i + 1].lat
    ) {
      totalDistance = totalDistance;
    }
    totalDistance =
      totalDistance +
      getDistanceBetweenTwoPoints(coordinates[i], coordinates[i + 1]);
  }

  return totalDistance.toFixed(2);
}

remove table row with specific id

Simply $("#3").remove(); would be enough. But 3 isn't a good id (I think it's even illegal, as it starts with a digit).

Remove multiple whitespaces

Without preg_replace()

$str = "This is   a Text \n and so on \t     Text text.";
$str = str_replace(["\r", "\n", "\t"], " ", $str);
while (strpos($str, "  ") !== false)
{
    $str = str_replace("  ", " ", $str);
}
echo $str;

How do you calculate the variance, median, and standard deviation in C++ or Java?

To calculate the mean, loop through the list/array of numbers, keeping track of the partial sums and the length. Then return the sum/length.

double sum = 0.0;
int length = 0;

for( double number : numbers ) {
    sum += number;
    length++;
}

return sum/length;

Variance is calculated similarly. Standard deviation is simply the square root of the variance:

double stddev = Math.sqrt( variance );

Exploring Docker container's file system

The docker exec command to run a command in a running container can help in multiple cases.


Usage:  docker exec [OPTIONS] CONTAINER COMMAND [ARG...]

Run a command in a running container

Options:
  -d, --detach               Detached mode: run command in the background
      --detach-keys string   Override the key sequence for detaching a
                             container
  -e, --env list             Set environment variables
  -i, --interactive          Keep STDIN open even if not attached
      --privileged           Give extended privileges to the command
  -t, --tty                  Allocate a pseudo-TTY
  -u, --user string          Username or UID (format:
                             [:])
  -w, --workdir string       Working directory inside the container

For example :

1) Accessing in bash to the running container filesystem :

docker exec -it containerId bash 

2) Accessing in bash to the running container filesystem as root to be able to have required rights :

docker exec -it -u root containerId bash  

This is particularly useful to be able to do some processing as root in a container.

3) Accessing in bash to the running container filesystem with a specific working directory :

docker exec -it -w /var/lib containerId bash 

Eclipse: Enable autocomplete / content assist

If you are only unfamiliar with the auto-complete while typing syntax or inbuilt methods in the eclipse you can simply type the desired syntax or method name and press Ctrl+Space that will display the list of desired options and you can select one of them.

If the auto-complete option is not enabled then you have to check your settings from Windows menu -> Preferences -> Java -> Editor -> Content assist

Why aren't python nested functions called closures?

The question has already been answered by aaronasterling

However, someone might be interested in how the variables are stored under the hood.

Before coming to the snippet:

Closures are functions that inherit variables from their enclosing environment. When you pass a function callback as an argument to another function that will do I/O, this callback function will be invoked later, and this function will — almost magically — remember the context in which it was declared, along with all the variables available in that context.

  • If a function does not use free variables it doesn't form a closure.

  • If there is another inner level which uses free variables -- all previous levels save the lexical environment ( example at the end )

  • function attributes func_closure in python < 3.X or __closure__ in python > 3.X save the free variables.

  • Every function in python has this closure attributes, but it doesn't save any content if there is no free variables.

example: of closure attributes but no content inside as there is no free variable.

>>> def foo():
...     def fii():
...         pass
...     return fii
...
>>> f = foo()
>>> f.func_closure
>>> 'func_closure' in dir(f)
True
>>>

NB: FREE VARIABLE IS MUST TO CREATE A CLOSURE.

I will explain using the same snippet as above:

>>> def make_printer(msg):
...     def printer():
...         print msg
...     return printer
...
>>> printer = make_printer('Foo!')
>>> printer()  #Output: Foo!

And all Python functions have a closure attribute so let's examine the enclosing variables associated with a closure function.

Here is the attribute func_closure for the function printer

>>> 'func_closure' in dir(printer)
True
>>> printer.func_closure
(<cell at 0x108154c90: str object at 0x108151de0>,)
>>>

The closure attribute returns a tuple of cell objects which contain details of the variables defined in the enclosing scope.

The first element in the func_closure which could be None or a tuple of cells that contain bindings for the function’s free variables and it is read-only.

>>> dir(printer.func_closure[0])
['__class__', '__cmp__', '__delattr__', '__doc__', '__format__', '__getattribute__',
 '__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', 
 '__setattr__',  '__sizeof__', '__str__', '__subclasshook__', 'cell_contents']
>>>

Here in the above output you can see cell_contents, let's see what it stores:

>>> printer.func_closure[0].cell_contents
'Foo!'    
>>> type(printer.func_closure[0].cell_contents)
<type 'str'>
>>>

So, when we called the function printer(), it accesses the value stored inside the cell_contents. This is how we got the output as 'Foo!'

Again I will explain using the above snippet with some changes:

 >>> def make_printer(msg):
 ...     def printer():
 ...         pass
 ...     return printer
 ...
 >>> printer = make_printer('Foo!')
 >>> printer.func_closure
 >>>

In the above snippet, I din't print msg inside the printer function, so it doesn't create any free variable. As there is no free variable, there will be no content inside the closure. Thats exactly what we see above.

Now I will explain another different snippet to clear out everything Free Variable with Closure:

>>> def outer(x):
...     def intermediate(y):
...         free = 'free'
...         def inner(z):
...             return '%s %s %s %s' %  (x, y, free, z)
...         return inner
...     return intermediate
...
>>> outer('I')('am')('variable')
'I am free variable'
>>>
>>> inter = outer('I')
>>> inter.func_closure
(<cell at 0x10c989130: str object at 0x10c831b98>,)
>>> inter.func_closure[0].cell_contents
'I'
>>> inn = inter('am')

So, we see that a func_closure property is a tuple of closure cells, we can refer them and their contents explicitly -- a cell has property "cell_contents"

>>> inn.func_closure
(<cell at 0x10c9807c0: str object at 0x10c9b0990>, 
 <cell at 0x10c980f68: str object at   0x10c9eaf30>, 
 <cell at 0x10c989130: str object at 0x10c831b98>)
>>> for i in inn.func_closure:
...     print i.cell_contents
...
free
am 
I
>>>

Here when we called inn, it will refer all the save free variables so we get I am free variable

>>> inn('variable')
'I am free variable'
>>>

how to open popup window using jsp or jquery?

Try this:

SCRIPT:

function winOpen()
{
    window.open("yourpage.jsp");
}

HTML:

<a href="javascript:;" onclick="winOpen()">Pop Up</a>

Read https://developer.mozilla.org/en/docs/DOM/window.open for window.open

Only mkdir if it does not exist

Do a test

[[ -d dir ]] || mkdir dir

Or use -p option:

mkdir -p dir

set environment variable in python script

bash:

LD_LIBRARY_PATH=my_path
sqsub -np $1 /path/to/executable

Similar, in Python:

import os
import subprocess
import sys

os.environ['LD_LIBRARY_PATH'] = "my_path" # visible in this process + all children
subprocess.check_call(['sqsub', '-np', sys.argv[1], '/path/to/executable'],
                      env=dict(os.environ, SQSUB_VAR="visible in this subprocess"))

How can I convert String to Int?

You need to parse the string, and you also need to ensure that it is truly in the format of an integer.

The easiest way is this:

int parsedInt = 0;
if (int.TryParse(TextBoxD1.Text, out parsedInt))
{
   // Code for if the string was valid
}
else
{
   // Code for if the string was invalid
}

npm install -g less does not work: EACCES: permission denied

sudo chown -R $USER /usr/local/lib/node_modules This command will work

Difference between "include" and "require" in php

require will throw a PHP Fatal Error if the file cannot be loaded. (Execution stops)

include produces a Warning if the file cannot be loaded. (Execution continues)

Here is a nice illustration of include and require difference:

enter image description here

From: Difference require vs. include php (by Robert; Nov 2012)

How do you add PostgreSQL Driver as a dependency in Maven?

<dependency>
    <groupId>org.postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <scope>runtime</scope>
</dependency>

@AspectJ pointcut for all methods of a class with specific annotation

Use

@Before("execution(* (@YourAnnotationAtClassLevel *).*(..))")
    public void beforeYourAnnotation(JoinPoint proceedingJoinPoint) throws Throwable {
}

How to specify a local file within html using the file: scheme?

The file: URL scheme refers to a file on the client machine. There is no hostname in the file: scheme; you just provide the path of the file. So, the file on your local machine would be file:///~User/2ndFile.html. Notice the three slashes; the hostname part of the URL is empty, so the slash at the beginning of the path immediately follows the double slash at the beginning of the URL. You will also need to expand the user's path; ~ does no expand in a file: URL. So you would need file:///home/User/2ndFile.html (on most Unixes), file:///Users/User/2ndFile.html (on Mac OS X), or file:///C:/Users/User/2ndFile.html (on Windows).

Many browsers, for security reasons, do not allow linking from a file that is loaded from a server to a local file. So, you may not be able to do this from a page loaded via HTTP; you may only be able to link to file: URLs from other local pages.

flow 2 columns of text automatically with CSS

Maybe a slightly tighter version? My use case is outputting college majors given a json array of majors (data).

var count_data      = data.length;

$.each( data, function( index ){
    var column = ( index < count_data/2 ) ? 1 : 2;
    $("#column"+column).append(this.name+'<br/>');
});

<div id="majors_view" class="span12 pull-left">

  <div class="row-fluid">
    <div class="span5" id="column1"> </div>
    <div class="span5 offset1" id="column2"> </div>
  </div>

</div>

How can I check the size of a collection within a Django template?

Collection.count no bracket

{% if request.user.is_authenticated %}
{{wishlists.count}}
{% else %}0{% endif %}

How to use regex with find command?

Judging from other answers, it seems this might be find's fault.

However you can do it this way instead:

find . * | grep -P "[a-f0-9\-]{36}\.jpg"

You might have to tweak the grep a bit and use different options depending on what you want but it works.

I have 2 dates in PHP, how can I run a foreach loop to go through all of those days?

Copy from php.net sample for inclusive range:

$begin = new DateTime( '2012-08-01' );
$end = new DateTime( '2012-08-31' );
$end = $end->modify( '+1 day' ); 

$interval = new DateInterval('P1D');
$daterange = new DatePeriod($begin, $interval ,$end);

foreach($daterange as $date){
    echo $date->format("Ymd") . "<br>";
}

How do I use extern to share variables between source files?

With xc8 you have to be careful about declaring a variable as the same type in each file as you could , erroneously, declare something an int in one file and a char say in another. This could lead to corruption of variables.

This problem was elegantly solved in a microchip forum some 15 years ago /* See "http:www.htsoft.com" / / "forum/all/showflat.php/Cat/0/Number/18766/an/0/page/0#18766"

But this link seems to no longer work...

So I;ll quickly try to explain it; make a file called global.h.

In it declare the following

#ifdef MAIN_C
#define GLOBAL
 /* #warning COMPILING MAIN.C */
#else
#define GLOBAL extern
#endif
GLOBAL unsigned char testing_mode; // example var used in several C files

Now in the file main.c

#define MAIN_C 1
#include "global.h"
#undef MAIN_C

This means in main.c the variable will be declared as an unsigned char.

Now in other files simply including global.h will have it declared as an extern for that file.

extern unsigned char testing_mode;

But it will be correctly declared as an unsigned char.

The old forum post probably explained this a bit more clearly. But this is a real potential gotcha when using a compiler that allows you to declare a variable in one file and then declare it extern as a different type in another. The problems associated with that are if you say declared testing_mode as an int in another file it would think it was a 16 bit var and overwrite some other part of ram, potentially corrupting another variable. Difficult to debug!

Apply CSS to jQuery Dialog Buttons

I suggest you take a look at the HTML that the code spits out and see if theres a way to uniquely identify one (or both) of the buttons (possibly the id or name attributes), then use jQuery to select that item and apply a css class to it.

How can I get a list of Git branches, ordered by most recent commit?

This is based on saeedgnu's version, but with the current branch shown with a star and in color, and only showing anything that is not described as "months" or "years" ago:

current_branch="$(git symbolic-ref --short -q HEAD)"
git for-each-ref --sort=committerdate refs/heads \
  --format='%(refname:short)|%(committerdate:relative)' \
  | grep -v '\(year\|month\)s\? ago' \
  | while IFS='|' read branch date
    do
      start='  '
      end=''
      if [[ $branch = $current_branch ]]; then
        start='* \e[32m'
        end='\e[0m'
      fi
      printf "$start%-30s %s$end\\n" "$branch" "$date"
    done

Python Finding Prime Factors

For prime number generation I always use Sieve of Eratosthenes:

def primes(n):
    if n<=2:
        return []
    sieve=[True]*(n+1)
    for x in range(3,int(n**0.5)+1,2):
        for y in range(3,(n//x)+1,2):
            sieve[(x*y)]=False

    return [2]+[i for i in range(3,n,2) if sieve[i]]

In [42]: %timeit primes(10**5)
10 loops, best of 3: 60.4 ms per loop

In [43]: %timeit primes(10**6)
1 loops, best of 3: 1.01 s per loop

You can use Miller-Rabin primality test to check whether a number is prime or not. You can find its Python implementations here.

Always use timeit module to time your code, the 2nd one takes just 15us:

def func():
    n = 600851475143
    i = 2
    while i * i < n:
         while n % i == 0:
            n = n / i
         i = i + 1

In [19]: %timeit func()
1000 loops, best of 3: 1.35 ms per loop

def func():
    i=1
    while i<100:i+=1
   ....:     

In [21]: %timeit func()
10000 loops, best of 3: 15.3 us per loop

How can I search for a multiline pattern in a file?

@Marcin: awk example non-greedy:

awk '{if ($0 ~ /Start pattern/) {triggered=1;}if (triggered) {print; if ($0 ~ /End pattern/) { exit;}}}' filename

How can I know if Object is String type object?

javamonkey79 is right. But don't forget what you might want to do (e.g. try something else or notify someone) if object is not an instance of String.

String myString;
if (object instanceof String) {
  myString = (String) object;
} else {
  // do something else     
}

BTW: If you use ClassCastException instead of Exception in your code above, you can be sure that you will catch the exception caused by casting object to String. And not any other exceptions caused by other code (e.g. NullPointerExceptions).

Windows 7 environment variable not working in path

%M2% and %JAVA_HOME% need to be added to a PATH variable in the USER variables, not the SYSTEM variables.

How can I get a specific number child using CSS?

For modern browsers, use td:nth-child(2) for the second td, and td:nth-child(3) for the third. Remember that these retrieve the second and third td for every row.

If you need compatibility with IE older than version 9, use sibling combinators or JavaScript as suggested by Tim. Also see my answer to this related question for an explanation and illustration of his method.

What difference between the DATE, TIME, DATETIME, and TIMESTAMP Types

I have a slightly different perspective on the difference between a DATETIME and a TIMESTAMP. A DATETIME stores a literal value of a date and time with no reference to any particular timezone. So, I can set a DATETIME column to a value such as '2019-01-16 12:15:00' to indicate precisely when my last birthday occurred. Was this Eastern Standard Time? Pacific Standard Time? Who knows? Where the current session time zone of the server comes into play occurs when you set a DATETIME column to some value such as NOW(). The value stored will be the current date and time using the current session time zone in effect. But once a DATETIME column has been set, it will display the same regardless of what the current session time zone is.

A TIMESTAMP column on the other hand takes the '2019-01-16 12:15:00' value you are setting into it and interprets it in the current session time zone to compute an internal representation relative to 1/1/1970 00:00:00 UTC. When the column is displayed, it will be converted back for display based on whatever the current session time zone is. It's a useful fiction to think of a TIMESTAMP as taking the value you are setting and converting it from the current session time zone to UTC for storing and then converting it back to the current session time zone for displaying.

If my server is in San Francisco but I am running an event in New York that starts on 9/1/1029 at 20:00, I would use a TIMESTAMP column for holding the start time, set the session time zone to 'America/New York' and set the start time to '2009-09-01 20:00:00'. If I want to know whether the event has occurred or not, regardless of the current session time zone setting I can compare the start time with NOW(). Of course, for displaying in a meaningful way to a perspective customer, I would need to set the correct session time zone. If I did not need to do time comparisons, then I would probably be better off just using a DATETIME column, which will display correctly (with an implied EST time zone) regardless of what the current session time zone is.

TIMESTAMP LIMITATION

The TIMESTAMP type has a range of '1970-01-01 00:00:01' UTC to '2038-01-19 03:14:07' UTC and so it may not usable for your particular application. In that case you will have to use a DATETIME type. You will, of course, always have to be concerned that the current session time zone is set properly whenever you are using this type with date functions such as NOW().

Where can I find error log files?

For unix cli users:

Most probably the error_log ini entry isn't set. To verify:

php -i | grep error_log
// error_log => no value => no value

You can either set it in your php.ini cli file, or just simply quickly pipe all STDERR yourself to a file:

./myprog 2> myerror.log

Then quickly:

tail -f myerror.log

Extract and delete all .gz in a directory- Linux

@techedemic is correct but is missing '.' to mention the current directory, and this command go throught all subdirectories.

find . -name '*.gz' -exec gunzip '{}' \;

How to unbind a listener that is calling event.preventDefault() (using jQuery)?

$('#my_elementtt').click(function(event){
    trigger('click');
});

How do I prevent Eclipse from hanging on startup?

I also had luck with removing the *.snap files. Mine were located in a different directory than mentioned in the posts (below).

<eclipse workspace>/.metadata/.plugins/org.eclipse.core.resources/.projects

Consequently, the following unix cmd did the trick:

find <eclipse_workspace>/.metadata/.plugins/org.eclipse.core.resources/.projects  -name "*.snap" -exec rm -f {} \;

ORA-29283: invalid file operation ORA-06512: at "SYS.UTL_FILE", line 536

I had been facing this problem for two days and I found that the directory you create in Oracle also needs to created first on your physical disk.

I didn't find this point mentioned anywhere i tried to look up the solution to this.

Example

If you created a directory, let's say, 'DB_DIR'.

CREATE OR REPLACE DIRECTORY DB_DIR AS 'E:\DB_WORKS';

Then you need to ensure that DB_WORKS exists in your E:\ drive and also file system level Read/Write permissions are available to the Oracle process.

My understanding of UTL_FILE from my experiences is given below for this kind of operation.

UTL_FILE is an object under SYS user. GRANT EXECUTE ON SYS.UTL_FILE TO PUBLIC; needs to given while logged in as SYS. Otherwise, it will give declaration error in procedure. Anyone can create a directory as shown:- CREATE OR REPLACE DIRECTORY DB_DIR AS 'E:\DBWORKS'; But CREATE DIRECTORY permission should be in place. This can be granted as shown:- GRANT CREATE ALL DIRECTORY TO user; while logged in as SYS user. However, if this needs to be used by another user, grants need to be given to that user otherwise it will throw error. GRANT READ, WRITE, EXECUTE ON DB_DIR TO user; while loggedin as the user who created the directory. Then, compile your package. Before executing the procedure, ensure that the Directory exists physically on your Disk. Otherwise it will throw 'Invalid File Operation' error. (V. IMPORTANT) Ensure that Filesystem level Read/Write permissions are in place for the Oracle process. This is separate from the DB level permissions granted.(V. IMPORTANT) Execute procedure. File should get populated with the result set of your query.

How to pass command line arguments to a shell alias?

Here's a simple example function using python. You can stick in ~/.bashrc
You gotta have a space after the first left curly bracket
The python command needs to be in double quotes to get the variable substitution
Don't forget that semicolon at the end

function count(){ python -c "for num in xrange($1):print num";}

$ count 6
0
1
2
3
4
5
$

Is there a command to restart computer into safe mode?

In the command prompt, type the command below and press Enter.

bcdedit /enum

Under the Windows Boot Loader sections, make note of the identifier value.

To start in safe mode from command prompt :

bcdedit /set {identifier} safeboot minimal 

Then enter the command line to reboot your computer.

How can I test a Windows DLL file to determine if it is 32 bit or 64 bit?

If you have Cygwin installed (which I strongly recommend for a variety of reasons), you could use the 'file' utility on the DLL

file <filename>

which would give an output like this:

icuuc36.dll: MS-DOS executable PE  for MS Windows (DLL) (GUI) Intel 80386 32-bit

How to get selenium to wait for ajax response?

If the control you are waiting for is an "Ajax" web element, the following code will wait for it, or any other Ajax web element to finish loading or performing whatever it needs to do so that you can more-safely continue with your steps.

    public static void waitForAjaxToFinish() {

    WebDriverWait wait = new WebDriverWait(driver, 10);

    wait.until(new ExpectedCondition<Boolean>() { 
        public Boolean apply(WebDriver wdriver) { 
            return ((JavascriptExecutor) driver).executeScript(
                    "return jQuery.active == 0").equals(true);
        }
    }); 

}

<xsl:variable> Print out value of XSL variable using <xsl:value-of>

In XSLT the same <xsl:variable> can be declared only once and can be given a value only at its declaration. If more than one variables are declared at the same time, they are in fact different variables and have different scope.

Therefore, the way to achieve the wanted conditional setting of the variable and producing its value is the following:

<xsl:stylesheet version="1.0"
 xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
 <xsl:output omit-xml-declaration="yes"/>

    <xsl:template match="class">
    <xsl:variable name="subexists">
            <xsl:choose>
                <xsl:when test="joined-subclass">true</xsl:when>
                <xsl:otherwise>false</xsl:otherwise>
            </xsl:choose>
        </xsl:variable>
        subexists:  <xsl:text/>    
        <xsl:value-of select="$subexists" />
    </xsl:template>
</xsl:stylesheet>

When the above transformation is applied on the following XML document:

<class>
 <joined-subclass/>
</class>

the wanted result is produced:

    subexists:  true

Closing WebSocket correctly (HTML5, Javascript)

According to the protocol spec v76 (which is the version that browser with current support implement):

To close the connection cleanly, a frame consisting of just a 0xFF byte followed by a 0x00 byte is sent from one peer to ask that the other peer close the connection.

If you are writing a server, you should make sure to send a close frame when the server closes a client connection. The normal TCP socket close method can sometimes be slow and cause applications to think the connection is still open even when it's not.

The browser should really do this for you when you close or reload the page. However, you can make sure a close frame is sent by doing capturing the beforeunload event:

window.onbeforeunload = function() {
    websocket.onclose = function () {}; // disable onclose handler first
    websocket.close();
};

I'm not sure how you can be getting an onclose event after the page is refreshed. The websocket object (with the onclose handler) will no longer exist once the page reloads. If you are immediately trying to establish a WebSocket connection on your page as the page loads, then you may be running into an issue where the server is refusing a new connection so soon after the old one has disconnected (or the browser isn't ready to make connections at the point you are trying to connect) and you are getting an onclose event for the new websocket object.

How do I control how Emacs makes backup files?

If you've ever been saved by an Emacs backup file, you probably want more of them, not less of them. It is annoying that they go in the same directory as the file you're editing, but that is easy to change. You can make all backup files go into a directory by putting something like the following in your .emacs.

(setq backup-directory-alist `(("." . "~/.saves")))

There are a number of arcane details associated with how Emacs might create your backup files. Should it rename the original and write out the edited buffer? What if the original is linked? In general, the safest but slowest bet is to always make backups by copying.

(setq backup-by-copying t)

If that's too slow for some reason you might also have a look at backup-by-copying-when-linked.

Since your backups are all in their own place now, you might want more of them, rather than less of them. Have a look at the Emacs documentation for these variables (with C-h v).

(setq delete-old-versions t
  kept-new-versions 6
  kept-old-versions 2
  version-control t)

Finally, if you absolutely must have no backup files:

(setq make-backup-files nil)

It makes me sick to think of it though.

Different CURRENT_TIMESTAMP and SYSDATE in oracle

SYSDATE returns the system date, of the system on which the database resides

CURRENT_TIMESTAMP returns the current date and time in the session time zone, in a value of datatype TIMESTAMP WITH TIME ZONE

execute this comman

    ALTER SESSION SET TIME_ZONE = '+3:0';

and it will provide you the same result.

Alternative for <blink>

_x000D_
_x000D_
.blink_text {_x000D_
_x000D_
    animation:1s blinker linear infinite;_x000D_
    -webkit-animation:1s blinker linear infinite;_x000D_
    -moz-animation:1s blinker linear infinite;_x000D_
_x000D_
     color: red;_x000D_
    }_x000D_
_x000D_
    @-moz-keyframes blinker {  _x000D_
     0% { opacity: 1.0; }_x000D_
     50% { opacity: 0.0; }_x000D_
     100% { opacity: 1.0; }_x000D_
     }_x000D_
_x000D_
    @-webkit-keyframes blinker {  _x000D_
     0% { opacity: 1.0; }_x000D_
     50% { opacity: 0.0; }_x000D_
     100% { opacity: 1.0; }_x000D_
     }_x000D_
_x000D_
    @keyframes blinker {  _x000D_
     0% { opacity: 1.0; }_x000D_
     50% { opacity: 0.0; }_x000D_
     100% { opacity: 1.0; }_x000D_
     }
_x000D_
    <span class="blink_text">India's Largest portal</span>
_x000D_
_x000D_
_x000D_

Ansible: get current target host's IP address

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

so in template, for e. g.:

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

Notes:

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

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

What does 'URI has an authority component' mean?

An authority is a portion of a URI. Your error suggests that it was not expecting one. The authority section is shown below, it is what is known as the website part of the url.

From RFC3986 on URIs:

The following is an example URI and its component parts:

     foo://example.com:8042/over/there?name=ferret#nose
     \_/   \______________/\_________/ \_________/ \__/
      |           |            |            |        |
   scheme     authority       path        query   fragment
      |   _____________________|__
     / \ /                        \
     urn:example:animal:ferret:nose

So there are two formats, one with an authority and one not. Regarding slashes:

"When authority is not present, the path cannot begin with two slash
characters ("//")."

Source: https://tools.ietf.org/rfc/rfc3986.txt (search for text 'authority is not present, the path cannot begin with two slash')

Removing multiple classes (jQuery)

The documentation says:

class (Optional) String
One or more CSS classes to remove from the elements, these are separated by spaces.

Example:

Remove the class 'blue' and 'under' from the matched elements.

$("p:odd").removeClass("blue under");

Fast Bitmap Blur For Android SDK

This worked fine for me: How to Blur Images Efficiently with Android's RenderScript

public class BlurBuilder {
    private static final float BITMAP_SCALE = 0.4f;
    private static final float BLUR_RADIUS = 7.5f;

    @SuppressLint("NewApi")
    public static Bitmap blur(Context context, Bitmap image) {
        int width = Math.round(image.getWidth() * BITMAP_SCALE);
        int height = Math.round(image.getHeight() * BITMAP_SCALE);

        Bitmap inputBitmap = Bitmap.createScaledBitmap(image, width, height,
            false);
        Bitmap outputBitmap = Bitmap.createBitmap(inputBitmap);

        RenderScript rs = RenderScript.create(context);
        ScriptIntrinsicBlur theIntrinsic = ScriptIntrinsicBlur.create(rs,
            Element.U8_4(rs));
        Allocation tmpIn = Allocation.createFromBitmap(rs, inputBitmap);
        Allocation tmpOut = Allocation.createFromBitmap(rs, outputBitmap);
        theIntrinsic.setRadius(BLUR_RADIUS);
        theIntrinsic.setInput(tmpIn);
        theIntrinsic.forEach(tmpOut);
        tmpOut.copyTo(outputBitmap);

        return outputBitmap;
    }
}

What is the javascript filename naming convention?

There is no official, universal, convention for naming JavaScript files.

There are some various options:

  • scriptName.js
  • script-name.js
  • script_name.js

are all valid naming conventions, however I prefer the jQuery suggested naming convention (for jQuery plugins, although it works for any JS)

  • jquery.pluginname.js

The beauty to this naming convention is that it explicitly describes the global namespace pollution being added.

  • foo.js adds window.foo
  • foo.bar.js adds window.foo.bar

Because I left out versioning: it should come after the full name, preferably separated by a hyphen, with periods between major and minor versions:

  • foo-1.2.1.js
  • foo-1.2.2.js
  • ...
  • foo-2.1.24.js

Are HTTPS headers encrypted?

HTTP version 1.1 added a special HTTP method, CONNECT - intended to create the SSL tunnel, including the necessary protocol handshake and cryptographic setup.
The regular requests thereafter all get sent wrapped in the SSL tunnel, headers and body inclusive.

Calling an executable program using awk

A much more robust way would be to use the getline() function of GNU awk to use a variable from a pipe. In form cmd | getline result, cmd is run, then its output is piped to getline. It returns 1 if got output, 0 if EOF, -1 on failure.

First construct the command to run in a variable in the BEGIN clause if the command is not dependant on the contents of the file, e.g. a simple date or an ls.

A simple example of the above would be

awk 'BEGIN {
    cmd = "ls -lrth"
    while ( ( cmd | getline result ) > 0 ) {
        print result
    }
    close(cmd);
}'

When the command to run is part of the columnar content of a file, you generate the cmd string in the main {..} as below. E.g. consider a file whose $2 contains the name of the file and you want it to be replaced with the md5sum hash content of the file. You can do

awk '{ cmd = "md5sum "$2
       while ( ( cmd | getline md5result ) > 0 ) { 
           $2 = md5result
       }
       close(cmd);
 }1'

Another frequent usage involving external commands in awk is during date processing when your awk does not support time functions out of the box with mktime(), strftime() functions.

Consider a case when you have Unix EPOCH timestamp stored in a column and you want to convert that to a human readable date format. Assuming GNU date is available

awk '{ cmd = "date -d @" $1 " +\"%d-%m-%Y %H:%M:%S\"" 
       while ( ( cmd | getline fmtDate) > 0 ) { 
           $1 = fmtDate
       }
       close(cmd);
}1' 

for an input string as

1572608319 foo bar zoo

the above command produces an output as

01-11-2019 07:38:39 foo bar zoo

The command can be tailored to modify the date fields on any of the columns in a given line. Note that -d is a GNU specific extension, the *BSD variants support -f ( though not exactly similar to -d).

More information about getline can be referred to from this AllAboutGetline article at awk.freeshell.org page.

Java program to get the current date without timestamp

Use DateFormat to solve this problem:

DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
DateFormat dateFormat2 = new SimpleDateFormat("MM-dd-yyyy");
print(dateFormat.format(new Date()); // will print like 2014-02-20
print(dateFormat2.format(new Date()); // will print like 02-20-2014

Convert JsonObject to String

You can try Gson convertor, to get the exact conversion like json.stringify

val jsonString:String = jsonObject.toString()
val gson:Gson = GsonBuilder().setPrettyPrinting().create()
val json:JsonElement = gson.fromJson(jsonString,JsonElement.class)
val jsonInString:String= gson.toJson(json)
println(jsonInString)

JQuery addclass to selected div, remove class if another div is selected

I had to transform the divs to list items otherwise all my divs would get that class and only the generated ones should get it Thanks everyone, I love this site and the helpful people on it !!!! You can follow the newbie school project at http://low-budgetwebservice.be/project/webbuilder.html suggestions are always welcome :). So this worked for me:

            /* Add Class Heading*/
            $(document).ready(function() {
            $( document ).on( 'click', 'ul#items li', function () { 
            $('ul#items li').removeClass('active'); 
            $(this).addClass('active');
            });
            });

How to free memory from char array in C

Local variables are automatically freed when the function ends, you don't need to free them by yourself. You only free dynamically allocated memory (e.g using malloc) as it's allocated on the heap:

char *arr = malloc(3 * sizeof(char));
strcpy(arr, "bo");
// ...
free(arr);

More about dynamic memory allocation: http://en.wikipedia.org/wiki/C_dynamic_memory_allocation

Configuring Log4j Loggers Programmatically

If someone comes looking for configuring log4j2 programmatically in Java, then this link could help: (https://www.studytonight.com/post/log4j2-programmatic-configuration-in-java-class)

Here is the basic code for configuring a Console Appender:

ConfigurationBuilder<BuiltConfiguration> builder = ConfigurationBuilderFactory.newConfigurationBuilder();

builder.setStatusLevel(Level.DEBUG);
// naming the logger configuration
builder.setConfigurationName("DefaultLogger");

// create a console appender
AppenderComponentBuilder appenderBuilder = builder.newAppender("Console", "CONSOLE")
                .addAttribute("target", ConsoleAppender.Target.SYSTEM_OUT);
// add a layout like pattern, json etc
appenderBuilder.add(builder.newLayout("PatternLayout")
                .addAttribute("pattern", "%d %p %c [%t] %m%n"));
RootLoggerComponentBuilder rootLogger = builder.newRootLogger(Level.DEBUG);
rootLogger.add(builder.newAppenderRef("Console"));

builder.add(appenderBuilder);
builder.add(rootLogger);
Configurator.reconfigure(builder.build());

This will reconfigure the default rootLogger and will also create a new appender.

Is there a way to programmatically scroll a scroll view to a specific edit text?

I made a small utility method based on Answer from WarrenFaith, this code also takes in account if that view is already visible in the scrollview, no need for scroll.

public static void scrollToView(final ScrollView scrollView, final View view) {

    // View needs a focus
    view.requestFocus();

    // Determine if scroll needs to happen
    final Rect scrollBounds = new Rect();
    scrollView.getHitRect(scrollBounds);
    if (!view.getLocalVisibleRect(scrollBounds)) {
        new Handler().post(new Runnable() {
            @Override
            public void run() {
                scrollView.smoothScrollTo(0, view.getBottom());
            }
        });
    } 
}

Reading a text file in MATLAB line by line

Just read it in to MATLAB in one block

fid = fopen('file.csv');
data=textscan(fid,'%s %f %f','delimiter',',');
fclose(fid);

You can then process it using logical addressing

ind50 = data{2}>=50 ;

ind50 is then an index of the rows where column 2 is greater than 50. So

data{1}(ind50)

will list all the strings for the rows of interest. Then just use fprintf to write out your data to the new file

How to check the multiple permission at single request in Android M?

For Asking Multiple Permission At Once You Can Use this Method link

compile 'com.kishan.askpermission:askpermission:1.0.3'

If you got conflicting in support library then

compile('com.kishan.askpermission:askpermission:1.0.3', {
    exclude group: 'com.android.support'
})

Now ask for Permission

new AskPermission.Builder(this)
    .setPermissions(Manifest.permission.READ_CONTACTS, Manifest.permission.WRITE_EXTERNAL_STORAGE)
    .setCallback(/* PermissionCallback */)
    .setErrorCallback(/* ErrorCallback */)
    .request(/* Request Code */);

permission granted callback

  public void onPermissionsGranted(int requestCode) {
// your code  }

permission denied callback

 public void onPermissionsDenied(int requestCode) {
// your code} 

ErrorCallbacks

public void onShowRationalDialog(PermissionInterface permissionInterface, int requestCode) {
// Alert user by Dialog or any other layout that you want.
// When user press OK you must need to call below method.
permissionInterface.onDialogShown();

}

public void onShowSettings(PermissionInterface permissionInterface, int requestCode) {
// Alert user by Dialog or any other layout that you want.
// When user press OK you must need to call below method.
// It will open setting screen.
permissionInterface.onSettingsShown();

}

Instantiating a generic class in Java

Quick solution that worked for me. I see there is already an answer for this and this may not even be the best way to go about it. Also, for my solution you'll need Gson.

However, I ran into a situation where I needed to create an instance of a generic class of type java.lang.reflect.Type.

The following code will create an instance of the class you want with null instance variables.

T object = new Gson().fromJson("{}", myKnownType);

Where myKnownType is known before hand and obtained via TypeToken.getType().

You can now set appropriate properties on this object. Again, this may not be the best way to do this but it works as a quick solution if that's what you need.

Testing for empty or nil-value string

variable = id if variable.to_s.empty?

The I/O operation has been aborted because of either a thread exit or an application request

995 is an error reported by the IO Completion Port. The error comes since you try to continue read from the socket when it has most likely been closed.

Receiving 0 bytes from EndRecieve means that the socket has been closed, as does most exceptions that EndRecieve will throw.

You need to start dealing with those situations.

Never ever ignore exceptions, they are thrown for a reason.

Update

There is nothing that says that the server does anything wrong. A connection can be lost for a lot of reasons such as idle connection being closed by a switch/router/firewall, shaky network, bad cables etc.

What I'm saying is that you MUST handle disconnections. The proper way of doing so is to dispose the socket and try to connect a new one at certain intervals.

As for the receive callback a more proper way of handling it is something like this (semi pseudo code):

public void OnDataReceived(IAsyncResult asyn)
{
    BLCommonFunctions.WriteLogger(0, "In :- OnDataReceived", ref swReceivedLogWriter, strLogPath, 0);

    try
    {
        SocketPacket client = (SocketPacket)asyn.AsyncState;

        int bytesReceived = client.thisSocket.EndReceive(asyn); //Here error is coming
        if (bytesReceived == 0)
        {
          HandleDisconnect(client);
          return;
        }
    }
    catch (Exception err)
    {
       HandleDisconnect(client);
    }

    try
    {
        string strHEX = BLCommonFunctions.ByteArrToHex(theSockId.dataBuffer);                    

        //do your handling here
    }
    catch (Exception err)
    {
        // Your logic threw an exception. handle it accordinhly
    }

    try
    {
       client.thisSocket.BeginRecieve(.. all parameters ..);
    }
    catch (Exception err)
    {
       HandleDisconnect(client);
    }
}

the reason to why I'm using three catch blocks is simply because the logic for the middle one is different from the other two. Exceptions from BeginReceive/EndReceive usually indicates socket disconnection while exceptions from your logic should not stop the socket receiving.

Spring - download response as a file

//JAVA PART

@RequestMapping(value = "/report-excel", method = RequestMethod.GET)
    public ResponseEntity<byte[]> getReportExcel(@RequestParam("bookingStatusType") String bookingStatusType,
            @RequestParam("endDate") String endDate, @RequestParam("product") String product, @RequestParam("startDate") String startDate)throws IOException, ParseException {

//Generate Excel from DTO using any logic after that do the following
byte[] body = wb.getBytes();
HttpHeaders header = new HttpHeaders();
        header.setContentType(new MediaType("application", "xlsx"));
        header.set("Content-Disposition", "inline; filename=" + fileName);
        header.setCacheControl("must-revalidate, post-check=0, pre-check=0");
        header.setContentLength(body.length);

 return new ResponseEntity<byte[]>(body, header, HttpStatus.OK);
}



//HTML PART
<html>
<head>
<title>Test</title>
<meta http-equiv="content-type" content="application/x-www-form-urlencoded; charset=UTF-8">
</head>
<body>
  <form name="downloadXLS" method="get" action="http://localhost:8080/rest/report-excel" enctype="multipart/form-data">
    <input type="text" name="bookingStatusType" value="SALES"></input>
    <input type="text" name="endDate" value="abcd"></input>
    <input type="text" name="product" value="FLIGHT"></input>
    <input type="text" name="startDate" value="abcd"></input>
    <input onclick="document.downloadXLS.submit()" value="Submit"></input>
  </form>
</body>
</html>

How do I get 'date-1' formatted as mm-dd-yyyy using PowerShell?

I think this is only partially true. Changing the format seems to switch the date to a string object which then has no methods like AddDays to manipulate it. So to make this work, you have to switch it back to a date. For example:

Get-Date (Get-Date).AddDays(-1) -format D

How to find the Center Coordinate of Rectangle?

The center of rectangle is the midpoint of the diagonal end points of rectangle.

Here the midpoint is ( (x1 + x2) / 2, (y1 + y2) / 2 ).

That means:
xCenter = (x1 + x2) / 2
yCenter = (y1 + y2) / 2

Let me know your code.

Is there a way to compile node.js source files?

I maybe very late but you can use "nexe" module that compile nodejs + your script in one executable: https://github.com/crcn/nexe

Git error on commit after merge - fatal: cannot do a partial commit during a merge

I solved this with a completely different approach, using only Xcode's Source Control.

Background: Another team Pushed changes to the remote Git repository (via Beanstalk). On my end, the .xcodeproj files came in under different directory, and the changes didn't take. Later, when I tried to commit, I received a Tree Conflict error in Xcode.

Tree Conflict Screenshot

Being nearly impossible to correct using Xcode, I replaced the .xcodeproj file with a downloaded version from the Git server. The result... the Xcode project appeared to clear up, however all the updates from the corrupt Pull were showing up as changes I made and were Staged for a Commit.

Look at all these Mods and Added files

However when trying to Commit, I received the same "fatal: cannot do a partial commit during a merge" error, discussed here.

Here's how I solved the problem... (Now, understand that I'm a rookie programmer, so I could lack some understanding... but my ignorance led me to find another way to do this.) First, I Cloned my master Branch into a secondary Branch and switched to that branch. Then I created a Working Copy and placed the directory to that working copy outside of the original project directory. (I don't know if this was necessary, but its what I did as I read other troubleshooting techniques.) Then I switched branches to the master, where I realized all my Staged files (changes to Commit) were gone. To make sure all the files were updated to the latest changes made by the other party, I created a new branch called ThirdBranch, which duplicated all files, Pushed it to the Git Server and let Beanstalk compare my server version of the master branch to the ThirdBrach branch I just Pushed (line by line), and all the changes by the other party were present on my Xcode. This meant that my master repository and the Git master repository were the same, which verifies that I solved the problem using Xcode, only.

Don't ask me how, beyond what I just described... and certainly fill in the gaps I left out. I'm new at this and I don't understand everything. Maybe an experienced programmer can separate the irrelevant info from the relevant and recreate this technique more clearly, which is in part why I'm posting this.

This is a duplicate answer to duplicate question as at: Failed Xcode Git Merge is stuck

where is gacutil.exe?

gacutil comes with Visual Studio, not with VSTS. It is part of Windows SDK and can be download separately at http://www.microsoft.com/downloads/details.aspx?FamilyId=F26B1AA4-741A-433A-9BE5-FA919850BDBF&displaylang=en . This installation will have gacutil.exe included. But first check it here

C:\Program Files\Microsoft SDKs\Windows\v6.0A\bin

you might have it installed.

As @devi mentioned

If you decide to grab gacutil files from existing installation, note that from .NET 4.0 is three files: gacutil.exe gacutil.exe.config and 1033/gacutlrc.dll

Android Gradle Apache HttpClient does not exist?

I suggest you replace the deprecated apache HttpClient with the new HttpURLConnection.

That's a cleaner solution, it's quite easy to migrate, and generally it's better to stick to the latest SDK changes than trying to hack/patch/workaround: you usually regret it later :)

Step 1

HttpGet httpGet = new HttpGet(url);

becomes:

URL urlObj = new URL(url);

Step 2

HttpClient httpClient = new DefaultHttpClient();
HttpContext localContext = new BasicHttpContext();
HttpResponse response = httpClient.execute(httpGet, localContext);
InputStream is = response.getEntity().getContent();

becomes:

HttpURLConnection urlConnection = (HttpURLConnection) urlObj.openConnection();
InputStream is = urlConnection.getInputStream();

Step 2 bis

int status = response.getStatusLine().getStatusCode();

becomes:

int status = urlConnection.getResponseCode();

How can I add a key/value pair to a JavaScript object?

A short and elegant way in next Javascript specification (candidate stage 3) is:

obj = { ... obj, ... { key3 : value3 } }

A deeper discussion can be found in Object spread vs Object.assign and on Dr. Axel Rauschmayers site.

It works already in node.js since release 8.6.0.

Vivaldi, Chrome, Opera, and Firefox in up to date releases know this feature also, but Mirosoft don't until today, neither in Internet Explorer nor in Edge.

CSS selector for a checked radio button's label

UPDATE:

This only worked for me because our existing generated html was wacky, generating labels along with radios and giving them both checked attribute.

Never mind, and big ups for Brilliand for bringing it up!

If your label is a sibling of a checkbox (which is usually the case), you can use the ~ sibling selector, and a label[for=your_checkbox_id] to address it... or give the label an id if you have multiple labels (like in this example where I use labels for buttons)


Came here looking for the same - but ended up finding my answer in the docs.

a label element with checked attribute can be selected like so:

label[checked] {
  ...
}

I know it's an old question, but maybe it helps someone out there :)

How can I show/hide component with JSF?

You can actually accomplish this without JavaScript, using only JSF's rendered attribute, by enclosing the elements to be shown/hidden in a component that can itself be re-rendered, such as a panelGroup, at least in JSF2. For example, the following JSF code shows or hides one or both of two dropdown lists depending on the value of a third. An AJAX event is used to update the display:

<h:selectOneMenu value="#{workflowProcEditBean.performedBy}">
    <f:selectItem itemValue="O" itemLabel="Originator" />
    <f:selectItem itemValue="R" itemLabel="Role" />
    <f:selectItem itemValue="E" itemLabel="Employee" />
    <f:ajax event="change" execute="@this" render="perfbyselection" />
</h:selectOneMenu>
<h:panelGroup id="perfbyselection">
    <h:selectOneMenu id="performedbyroleid" value="#{workflowProcEditBean.performedByRoleID}"
                     rendered="#{workflowProcEditBean.performedBy eq 'R'}">
        <f:selectItem itemLabel="- Choose One -" itemValue="" />
        <f:selectItems value="#{workflowProcEditBean.roles}" />
    </h:selectOneMenu>
    <h:selectOneMenu id="performedbyempid" value="#{workflowProcEditBean.performedByEmpID}"
                     rendered="#{workflowProcEditBean.performedBy eq 'E'}">
        <f:selectItem itemLabel="- Choose One -" itemValue="" />
        <f:selectItems value="#{workflowProcEditBean.employees}" />
    </h:selectOneMenu>
</h:panelGroup>

Why does an image captured using camera intent gets rotated on some devices on Android?

If somebody experiences problems with ExifInterface on Android 4.4 (KitKat) for getting the orientation, it might be because of wrong path got from the URI. See a solution for propoer getPath in Stack Overflow question Get real path from URI, Android KitKat new storage access framework

How do I use NSTimer?

Something like this:

NSTimer *timer;

    timer = [NSTimer scheduledTimerWithTimeInterval: 0.5
                     target: self
                     selector: @selector(handleTimer:)
                     userInfo: nil
                     repeats: YES];

Visual Studio : short cut Key : Duplicate Line

I use application link:AutoHotkey with below code saved in CommentDuplikateSaveClipboard.ahk file. You can edit/remove shortcuts it is easy.
I have link to this file "Shortcut to CommentDuplikateSaveClipboard.ahk" in Autostart in windows.
This script protect your clipboard.
If you are more curious you would add shortcuts to thisable/enable script.
I sometimes use very impressive Multi Clipboard script to easy handle with many clips saved on disk and use with CTRL+C,X,V to copy,paste,cut,next,previous,delete this,delete all.

;CommentDuplikateSaveClipboard.ahk

!c:: ; Alt+C === Duplicate Line
^d:: ; Ctrl+D
ClipSaved := ClipboardAll
Send, {END}{SHIFTDOWN}{HOME}{SHIFTUP}{CTRLDOWN}c{CTRLUP}{END}{ENTER}{CTRLDOWN}v{CTRLUP}{HOME}
Clipboard := ClipSaved
ClipSaved =
return

!x:: ; Alt+X === Comment Duplicate Line
ClipSaved := ClipboardAll
Send, {END}{SHIFTDOWN}{HOME}{SHIFTUP}{CTRLDOWN}c{CTRLUP}{LEFT}//{END}{ENTER}{CTRLDOWN}v{CTRLUP}{HOME}
Clipboard := ClipSaved
ClipSaved =
return

!z:: ; Alt+Z === Del uncomment  Line
ClipSaved := ClipboardAll
Send, {END}{SHIFTDOWN}{UP}{END}{SHIFTUP}{DEL}{HOME}{DEL}{DEL}
Clipboard := ClipSaved
ClipSaved =
return

!d:: ; Alt+D === Delete line
Send, {END}{SHIFTDOWN}{UP}{END}{SHIFTUP}{DEL}
return

!s:: ; Alt+S === Swap lines
ClipSaved := ClipboardAll
Send, {END}{SHIFTDOWN}{UP}{END}{SHIFTUP}{CTRLDOWN}x{CTRLUP}{UP}{END}{CTRLDOWN}v{CTRLUP}{HOME}
Clipboard := ClipSaved
ClipSaved =
return

!a:: ; Alt+A === Comment this line, uncomment above
Send, {END}{HOME}//{UP}{HOME}{DEL}{DEL}
return

Using port number in Windows host file

-You can use any free address in the network 127.0.0.0/8 , in my case needed this for python flask and this is what I have done : add this line in the hosts file (you can find it is windows under : C:\Windows\System32\drivers\etc ) :

127.0.0.5 flask.dev
  • Make sure the port is the default port "80" in my case this is what in the python flask: app.run("127.0.0.5","80")

  • now run your code and browse flask.dev

How do I configure Notepad++ to use spaces instead of tabs?

I have NotePad++ v6.8.3, and it was in Settings ? Preferences ? Tab Settings ? [Default] ? Replace by space:

NotePad++ Preferences

NotePad++ Tab Settings

How to identify numpy types in python?

Old question but I came up with a definitive answer with an example. Can't hurt to keep questions fresh as I had this same problem and didn't find a clear answer. The key is to make sure you have numpy imported, and then run the isinstance bool. While this may seem simple, if you are doing some computations across different data types, this small check can serve as a quick test before your start some numpy vectorized operation.

##################
# important part!
##################

import numpy as np

####################
# toy array for demo
####################

arr = np.asarray(range(1,100,2))

########################
# The instance check
######################## 

isinstance(arr,np.ndarray)

Replace multiple characters in one replace call

yourstring = '#Please send_an_information_pack_to_the_following_address:';

replace '#' with '' and replace '_' with a space

var newstring1 = yourstring.split('#').join('');
var newstring2 = newstring1.split('_').join(' ');

newstring2 is your result

Why are Python's 'private' methods not actually private?

The class.__stuff naming convention lets the programmer know he isn't meant to access __stuff from outside. The name mangling makes it unlikely anyone will do it by accident.

True, you still can work around this, it's even easier than in other languages (which BTW also let you do this), but no Python programmer would do this if he cares about encapsulation.

How to make a div with a circular shape?

You can do following

FIDDLE

<div id="circle"></div>

CSS

#circle {
    width: 100px;
    height: 100px;
    background: red;
    -moz-border-radius: 50px;
    -webkit-border-radius: 50px;
    border-radius: 50px;
}

Other shape SOURCE

What's the difference between Sender, From and Return-Path?

The official RFC which defines this specification could be found here:

http://tools.ietf.org/html/rfc4021#section-2.1.2 (look at paragraph 2.1.2. and the following)

2.1.2. Header Field: From

Description:  
    Mailbox of message author  
[...]  
Related information:
    Specifies the author(s) of the message; that is, the mailbox(es)
    of the person(s) or system(s) responsible for the writing of the
    message. Defined as standard by RFC 822.

2.1.3. Header Field: Sender

Description:  
    Mailbox of message sender  
[...]  
Related information:
    Specifies the mailbox of the agent responsible for the actual
    transmission of the message.  Defined as standard by RFC 822.

2.1.22. Header Field: Return-Path

Description:
    Message return path
[...]  
Related information:
    Return path for message response diagnostics. See also RFC 2821
    [17]. Defined as standard by RFC 822.

Python wildcard search in string

Easy method is try os.system:

import os
text = 'this is text'
os.system("echo %s | grep 't*'" % text)

Using LINQ to group by multiple properties and sum

Linus is spot on in the approach, but a few properties are off. It looks like 'AgencyContractId' is your Primary Key, which is unrelated to the output you want to give the user. I think this is what you want (assuming you change your ViewModel to match the data you say you want in your view).

var agencyContracts = _agencyContractsRepository.AgencyContracts
    .GroupBy(ac => new
                   {
                       ac.AgencyID,
                       ac.VendorID,
                       ac.RegionID
                   })
    .Select(ac => new AgencyContractViewModel
                   {
                       AgencyId = ac.Key.AgencyID,
                       VendorId = ac.Key.VendorID,
                       RegionId = ac.Key.RegionID,
                       Total = ac.Sum(acs => acs.Amount) + ac.Sum(acs => acs.Fee)
                   });

How to redirect all HTTP requests to HTTPS

A different edge to this problem is when a Load Balancer comes into play.

The situation is as follows: - Traffic from browser to Load Balancer, and back, is (should be) HTTPS - Traffic between Load Balancer and actual WebServer is HTTP.

So, all server request variables in PHP or Apache show that the connection is just HTTP. And the HTTP and HTTPS directories on the Server are the same.

The RewriteCondition in the approved answer does not work. It gives either a loop or it just doesn't work.

Question is: How to get this working on a Load Balancer.

(Or is the Load Balancer configured wrong. Which is what I'm hoping for because then I can move the problem over to the WebHosting company :-) )

HTML tag inside JavaScript

If you write HTML into javascript anywhere, it will think the HTML is written in javascript. The best way to include HTML in JavaScript is to write the HTML code on the page. The browser can't display HTML tags, so the browser will recognize the HTML and write this code in HTML.

document.write("<p>Hello World!</p>");

Though if you would like to write HTML on a function, GetElementById is the best:

function functionName() {
   document.getElementById(" the id of the HTML element to be written in ").innerHTML = "whatever you want to say"
}

Hope this helps!

removing table border

Most of the time your background color is different from the background of your table. Since there are spaces between the cells, those spaces will create the illusion of lines with the color of the background behind the table.

The solution is to get rid of those spaces.

Inside the table tag write:

cellspacing="0"

JSON character encoding - is UTF-8 well-supported by browsers or should I use numeric escape sequences?

The JSON spec requires UTF-8 support by decoders. As a result, all JSON decoders can handle UTF-8 just as well as they can handle the numeric escape sequences. This is also the case for Javascript interpreters, which means JSONP will handle the UTF-8 encoded JSON as well.

The ability for JSON encoders to use the numeric escape sequences instead just offers you more choice. One reason you may choose the numeric escape sequences would be if a transport mechanism in between your encoder and the intended decoder is not binary-safe.

Another reason you may want to use numeric escape sequences is to prevent certain characters appearing in the stream, such as <, & and ", which may be interpreted as HTML sequences if the JSON code is placed without escaping into HTML or a browser wrongly interprets it as HTML. This can be a defence against HTML injection or cross-site scripting (note: some characters MUST be escaped in JSON, including " and \).

Some frameworks, including PHP's implementation of JSON, always do the numeric escape sequences on the encoder side for any character outside of ASCII. This is intended for maximum compatibility with limited transport mechanisms and the like. However, this should not be interpreted as an indication that JSON decoders have a problem with UTF-8.

So, I guess you just could decide which to use like this:

  • Just use UTF-8, unless your method of storage or transport between encoder and decoder is not binary-safe.

  • Otherwise, use the numeric escape sequences.

Checking if a variable is initialized

If for instance you use strings instead of chars, you might be able do something like this:

    //a is a string of length 1
    string a;
    //b is the char in which we'll put the char stored in a
    char b;
    bool isInitialized(){
      if(a.length() != NULL){
        b = a[0];
        return true;
      }else return false;
    }

How to remove blank lines from a Unix file

awk 'NF' filename

awk 'NF > 0' filename

sed -i '/^$/d' filename

awk '!/^$/' filename

awk '/./' filename

The NF also removes lines containing only blanks or tabs, the regex /^$/ does not.

How do I search an SQL Server database for a string?

You can also try ApexSQL Search – it’s a free SSMS add-in similar to SQL Search.

If you really want to use only SQL you might want to try this script:

select
S.name as [Schema],
o.name as [Object],
o.type_desc as [Object_Type],
C.text as [Object_Definition]
from sys.all_objects O inner join sys.schemas S on O.schema_id = S.schema_id
inner join sys.syscomments C on O.object_id = C.id
where S.schema_id not in (3,4) -- avoid searching in sys and INFORMATION_SCHEMA schemas
and C.text like '%ICE_%'
order by [Schema]

How to convert int to date in SQL Server 2008

You have to first convert it into datetime, then to date.

Try this, it might be helpful:

Select Convert(DATETIME, LEFT(20130101, 8))

then convert to date.

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

The solution I opted for was to format the date with the mysql query :

String l_mysqlQuery = "SELECT DATE_FORMAT(time, '%Y-%m-%d %H:%i:%s') FROM uld_departure;"
l_importedTable = fStatement.executeQuery( l_mysqlQuery );
System.out.println(l_importedTable.getString( timeIndex));

I had the exact same issue. Even though my mysql table contains dates formatted as such : 2017-01-01 21:02:50

String l_mysqlQuery = "SELECT time FROM uld_departure;"
l_importedTable = fStatement.executeQuery( l_mysqlQuery );
System.out.println(l_importedTable.getString( timeIndex));

was returning a date formatted as such : 2017-01-01 21:02:50.0

Return value in a Bash function

The return statement sets the exit code of the function, much the same as exit will do for the entire script.

The exit code for the last command is always available in the $? variable.

function fun1(){
  return 34
}

function fun2(){
  local res=$(fun1)
  echo $? # <-- Always echos 0 since the 'local' command passes.

  res=$(fun1)
  echo $?  #<-- Outputs 34
}

Controlling a USB power supply (on/off) with Linux

I wanted to do this, and with my USB hardware I couldn't. I wrote a hacky way how to do it here:

http://pintant.cat/2012/05/12/power-off-usb-device/ .

In a short way: I used a USB relay to open/close the VCC of another USB cable...

Cannot use a CONTAINS or FREETEXT predicate on table or indexed view because it is not full-text indexed

  1. Make sure you have full-text search feature installed.

    Full-Text Search setup

  2. Create full-text search catalog.

     use AdventureWorks
     create fulltext catalog FullTextCatalog as default
    
     select *
     from sys.fulltext_catalogs
    
  3. Create full-text search index.

     create fulltext index on Production.ProductDescription(Description)
     key index PK_ProductDescription_ProductDescriptionID
    

    Before you create the index, make sure:
    - you don't already have full-text search index on the table as only one full-text search index allowed on a table
    - a unique index exists on the table. The index must be based on single-key column, that does not allow NULL.
    - full-text catalog exists. You have to specify full-text catalog name explicitly if there is no default full-text catalog.

You can do step 2 and 3 in SQL Sever Management Studio. In object explorer, right click on a table, select Full-Text index menu item and then Define Full-Text Index... sub-menu item. Full-Text indexing wizard will guide you through the process. It will also create a full-text search catalog for you if you don't have any yet.

enter image description here

You can find more info at MSDN

Convert DataTable to List<T>

There is a little example that you can use

            DataTable dt = GetCustomersDataTable(null);            

            IEnumerable<SelectListItem> lstCustomer = dt.AsEnumerable().Select(x => new SelectListItem()
            {
                Value = x.Field<string>("CustomerId"),
                Text = x.Field<string>("CustomerDescription")
            }).ToList();

            return lstCustomer;

WRONGTYPE Operation against a key holding the wrong kind of value php

I faced this issue when trying to set something to redis. The problem was that I previously used "set" method to set data with a certain key, like

$redis->set('persons', $persons)

Later I decided to change to "hSet" method, and I tried it this way

foreach($persons as $person){
    $redis->hSet('persons', $person->id, $person);
}

Then I got the aforementioned error. So, what I had to do is to go to redis-cli and manually delete "persons" entry with

del persons

It simply couldn't write different data structure under existing key, so I had to delete the entry and hSet then.

How can I find last row that contains data in a specific column?

Sub test()
    MsgBox Worksheets("sheet_name").Range("A65536").End(xlUp).Row
End Sub

This is looking for a value in column A because of "A65536".

commands not found on zsh

It's evident that you've managed to mess up your PATH variable. (Your current PATH doesn't contain any location where common utilities are located.)

Try:

PATH=/bin:/usr/bin:/usr/local/bin:${PATH}
export PATH

Alternatively, for "resetting" zsh, specify the complete path to the shell:

exec /bin/zsh

or

exec /usr/bin/zsh

Simulate a specific CURL in PostMan

As mentioned in multiple answers above you can import the cURL in POSTMAN directly. But if URL is authorized (or is not working for some reason) ill suggest you can manually add all the data points as JSON in your postman body. take the API URL from the cURL.

for the Authorization part- just add an Authorization key and base 64 encoded string as value.

example:

curl -u rzp_test_26ccbdbfe0e84b:69b2e24411e384f91213f22a \ https://api.razorpay.com/v1/orders -X POST \ --data "amount=50000" \ --data "currency=INR" \ --data "receipt=Receipt #20" \ --data "payment_capture=1" https://api.razorpay.com/v1/orders

{ "amount": "5000", "currency": "INR", "receipt": "Receipt #20", "payment_capture": "1" }

Headers: Authorization:Basic cnpwX3Rlc3RfWEk5QW5TU0N3RlhjZ0Y6dURjVThLZ3JiQVVnZ3JNS***U056V25J where "cnpwX3Rlc3RfWEk5QW5TU0N3RlhjZ0Y6dURjVThLZ3JiQVVnZ3JNS***U056V25J" is the encoded form of "rzp_test_26ccbdbfe0e84b:69b2e24411e384f91213f22a"`

small tip: for encoding, you can easily go to your chrome console (right-click => inspect) and type : btoa("string you want to encode") ( or use postman basic authorization)

How do I check for equality using Spark Dataframe without SQL Query?

df.filter($"state" like "T%%") for pattern matching

df.filter($"state" === "TX") or df.filter("state = 'TX'") for equality

libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)

Only the "drop armageddon" solution worked for me:

  • remove app from device
  • clean project
  • run new install on device

How do I print the elements of a C++ vector in GDB?

put the following in ~/.gdbinit

define print_vector
    if $argc == 2
        set $elem = $arg0.size()
        if $arg1 >= $arg0.size()
            printf "Error, %s.size() = %d, printing last element:\n", "$arg0", $arg0.size()
            set $elem = $arg1 -1
        end
        print *($arg0._M_impl._M_start + $elem)@1
    else
        print *($arg0._M_impl._M_start)@$arg0.size()
    end
end

document print_vector
Display vector contents
Usage: print_vector VECTOR_NAME INDEX
VECTOR_NAME is the name of the vector
INDEX is an optional argument specifying the element to display
end

After restarting gdb (or sourcing ~/.gdbinit), show the associated help like this

gdb) help print_vector
Display vector contents
Usage: print_vector VECTOR_NAME INDEX
VECTOR_NAME is the name of the vector
INDEX is an optional argument specifying the element to display

Example usage:

(gdb) print_vector videoconfig_.entries 0
$32 = {{subChannelId = 177 '\261', sourceId = 0 '\000', hasH264PayloadInfo = false, bitrate = 0,     payloadType = 68 'D', maxFs = 0, maxMbps = 0, maxFps = 134, encoder = 0 '\000', temporalLayers = 0 '\000'}}

Javascript checkbox onChange

HTML:

<input type="checkbox" onchange="handleChange(event)">

JS:

function handleChange(e) {
     const {checked} = e.target;
}

How can I list all foreign keys referencing a given table in SQL Server?

Working off of what @Gishu did I was able to produce and use the following SQL in SQL Server 2005

SELECT t.name AS TableWithForeignKey, fk.constraint_column_id AS FK_PartNo, 
       c.name AS ForeignKeyColumn, o.name AS FK_Name 
  FROM sys.foreign_key_columns AS fk
       INNER JOIN sys.tables AS t ON fk.parent_object_id = t.object_id
       INNER JOIN sys.columns AS c ON fk.parent_object_id = c.object_id 
                                  AND fk.parent_column_id = c.column_id
       INNER JOIN sys.objects AS o ON fk.constraint_object_id = o.object_id
  WHERE fk.referenced_object_id = (SELECT object_id FROM sys.tables 
                                        WHERE name = 'TableOthersForeignKeyInto')
  ORDER BY TableWithForeignKey, FK_PartNo;

Which Displays the tables, columns and Foreign Key names all in 1 query.

What are the ways to make an html link open a folder

Does not work in Chrome, but this other answers suggests a solution via a plugin:

Can Google Chrome open local links?

Disable the postback on an <ASP:LinkButton>

No one seems to be doing it like this:

createEventLinkButton.Attributes.Add("onClick", " if (this.innerHTML == 'Please Wait') { return false; } else {  this.innerHTML='Please Wait'; }");

This seems to be the only way that works.

How to read a CSV file into a .NET Datatable

Use this, one function solve all problems of comma and quote:

public static DataTable CsvToDataTable(string strFilePath)
    {

        if (File.Exists(strFilePath))
        {

            string[] Lines;
            string CSVFilePathName = strFilePath;

            Lines = File.ReadAllLines(CSVFilePathName);
            while (Lines[0].EndsWith(","))
            {
                Lines[0] = Lines[0].Remove(Lines[0].Length - 1);
            }
            string[] Fields;
            Fields = Lines[0].Split(new char[] { ',' });
            int Cols = Fields.GetLength(0);
            DataTable dt = new DataTable();
            //1st row must be column names; force lower case to ensure matching later on.
            for (int i = 0; i < Cols; i++)
                dt.Columns.Add(Fields[i], typeof(string));
            DataRow Row;
            int rowcount = 0;
            try
            {
                string[] ToBeContinued = new string[]{};
                bool lineToBeContinued = false;
                for (int i = 1; i < Lines.GetLength(0); i++)
                {
                    if (!Lines[i].Equals(""))
                    {
                        Fields = Lines[i].Split(new char[] { ',' });
                        string temp0 = string.Join("", Fields).Replace("\"\"", "");
                        int quaotCount0 = temp0.Count(c => c == '"');
                        if (Fields.GetLength(0) < Cols || lineToBeContinued || quaotCount0 % 2 != 0)
                        {
                            if (ToBeContinued.GetLength(0) > 0)
                            {
                                ToBeContinued[ToBeContinued.Length - 1] += "\n" + Fields[0];
                                Fields = Fields.Skip(1).ToArray();
                            }
                            string[] newArray = new string[ToBeContinued.Length + Fields.Length];
                            Array.Copy(ToBeContinued, newArray, ToBeContinued.Length);
                            Array.Copy(Fields, 0, newArray, ToBeContinued.Length, Fields.Length);
                            ToBeContinued = newArray;
                            string temp = string.Join("", ToBeContinued).Replace("\"\"", "");
                            int quaotCount = temp.Count(c => c == '"');
                            if (ToBeContinued.GetLength(0) >= Cols && quaotCount % 2 == 0 )
                            {
                                Fields = ToBeContinued;
                                ToBeContinued = new string[] { };
                                lineToBeContinued = false;
                            }
                            else
                            {
                                lineToBeContinued = true;
                                continue;
                            }
                        }

                        //modified by Teemo @2016 09 13
                        //handle ',' and '"'
                        //Deserialize CSV following Excel's rule:
                        // 1: If there is commas in a field, quote the field.
                        // 2: Two consecutive quotes indicate a user's quote.

                        List<int> singleLeftquota = new List<int>();
                        List<int> singleRightquota = new List<int>();

                        //combine fileds if number of commas match
                        if (Fields.GetLength(0) > Cols) 
                        {
                            bool lastSingleQuoteIsLeft = true;
                            for (int j = 0; j < Fields.GetLength(0); j++)
                            {
                                bool leftOddquota = false;
                                bool rightOddquota = false;
                                if (Fields[j].StartsWith("\"")) 
                                {
                                    int numberOfConsecutiveQuotes = 0;
                                    foreach (char c in Fields[j]) //start with how many "
                                    {
                                        if (c == '"')
                                        {
                                            numberOfConsecutiveQuotes++;
                                        }
                                        else
                                        {
                                            break;
                                        }
                                    }
                                    if (numberOfConsecutiveQuotes % 2 == 1)//start with odd number of quotes indicate system quote
                                    {
                                        leftOddquota = true;
                                    }
                                }

                                if (Fields[j].EndsWith("\""))
                                {
                                    int numberOfConsecutiveQuotes = 0;
                                    for (int jj = Fields[j].Length - 1; jj >= 0; jj--)
                                    {
                                        if (Fields[j].Substring(jj,1) == "\"") // end with how many "
                                        {
                                            numberOfConsecutiveQuotes++;
                                        }
                                        else
                                        {
                                            break;
                                        }
                                    }

                                    if (numberOfConsecutiveQuotes % 2 == 1)//end with odd number of quotes indicate system quote
                                    {
                                        rightOddquota = true;
                                    }
                                }
                                if (leftOddquota && !rightOddquota)
                                {
                                    singleLeftquota.Add(j);
                                    lastSingleQuoteIsLeft = true;
                                }
                                else if (!leftOddquota && rightOddquota)
                                {
                                    singleRightquota.Add(j);
                                    lastSingleQuoteIsLeft = false;
                                }
                                else if (Fields[j] == "\"") //only one quota in a field
                                {
                                    if (lastSingleQuoteIsLeft)
                                    {
                                        singleRightquota.Add(j);
                                    }
                                    else
                                    {
                                        singleLeftquota.Add(j);
                                    }
                                }
                            }
                            if (singleLeftquota.Count == singleRightquota.Count)
                            {
                                int insideCommas = 0;
                                for (int indexN = 0; indexN < singleLeftquota.Count; indexN++)
                                {
                                    insideCommas += singleRightquota[indexN] - singleLeftquota[indexN];
                                }
                                if (Fields.GetLength(0) - Cols >= insideCommas) //probabaly matched
                                {
                                    int validFildsCount = insideCommas + Cols; //(Fields.GetLength(0) - insideCommas) may be exceed the Cols
                                    String[] temp = new String[validFildsCount];
                                    int totalOffSet = 0;
                                    for (int iii = 0; iii < validFildsCount - totalOffSet; iii++)
                                    {
                                        bool combine = false;
                                        int storedIndex = 0;
                                        for (int iInLeft = 0; iInLeft < singleLeftquota.Count; iInLeft++)
                                        {
                                            if (iii + totalOffSet == singleLeftquota[iInLeft])
                                            {
                                                combine = true;
                                                storedIndex = iInLeft;
                                                break;
                                            }
                                        }
                                        if (combine)
                                        {
                                            int offset = singleRightquota[storedIndex] - singleLeftquota[storedIndex];
                                            for (int combineI = 0; combineI <= offset; combineI++)
                                            {
                                                temp[iii] += Fields[iii + totalOffSet + combineI] + ",";
                                            }
                                            temp[iii] = temp[iii].Remove(temp[iii].Length - 1, 1);
                                            totalOffSet += offset;
                                        }
                                        else
                                        {
                                            temp[iii] = Fields[iii + totalOffSet];
                                        }
                                    }
                                    Fields = temp;
                                }
                            }
                        }
                        Row = dt.NewRow();
                        for (int f = 0; f < Cols; f++)
                        {
                            Fields[f] = Fields[f].Replace("\"\"", "\""); //Two consecutive quotes indicate a user's quote
                            if (Fields[f].StartsWith("\""))
                            {
                                if (Fields[f].EndsWith("\""))
                                {
                                    Fields[f] = Fields[f].Remove(0, 1);
                                    if (Fields[f].Length > 0)
                                    {
                                        Fields[f] = Fields[f].Remove(Fields[f].Length - 1, 1);
                                    }
                                }
                            }
                            Row[f] = Fields[f];
                        }
                        dt.Rows.Add(Row);
                        rowcount++;
                    }
                }
            }
            catch (Exception ex)
            {
                throw new Exception( "row: " + (rowcount+2) + ", " + ex.Message);
            }
            //OleDbConnection connection = new OleDbConnection(string.Format(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0}; Extended Properties=""text;HDR=Yes;FMT=Delimited"";", FilePath + FileName));
            //OleDbCommand command = new OleDbCommand("SELECT * FROM " + FileName, connection);
            //OleDbDataAdapter adapter = new OleDbDataAdapter(command);
            //DataTable dt = new DataTable();
            //adapter.Fill(dt);
            //adapter.Dispose();
            return dt;
        }
        else
            return null;

        //OleDbConnection connection = new OleDbConnection(string.Format(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0}; Extended Properties=""text;HDR=Yes;FMT=Delimited"";", strFilePath));
        //OleDbCommand command = new OleDbCommand("SELECT * FROM " + strFileName, connection);
        //OleDbDataAdapter adapter = new OleDbDataAdapter(command);
        //DataTable dt = new DataTable();
        //adapter.Fill(dt);
        //return dt;
    }

Cocoa Autolayout: content hugging vs content compression resistance priority

Let's say you have a button with the text, "Click Me". What width should that button be?

First, you definitely don't want the button to be smaller than the text. Otherwise, the text would be clipped. This is the horizontal compression resistance priority.

Second, you don't want the button to be bigger than it needs to be. A button that looked like this, [          Click Me          ], is obviously too big. You want the button to "hug" its contents without too much padding. This is the horizontal content hugging priority. For a button, it isn't as strong as the horizontal compression resistance priority.

ASP.NET Web API : Correct way to return a 401/unauthorised response

As an alternative to the other answers, you can also use this code if you want to return an IActionResult within an ASP.NET controller.

ASP.NET

 return Content(HttpStatusCode.Unauthorized, "My error message");

Update: ASP.NET Core

Above code does not work in ASP.NET Core, you can use one of these instead:

 return StatusCode((int)System.Net.HttpStatusCode.Unauthorized, "My error message");
 return StatusCode(Microsoft.AspNetCore.Http.StatusCodes.Status401Unauthorized, "My error message");
 return StatusCode(401, "My error message");

Apparently the reason phrase is pretty optional (Can an HTTP response omit the Reason-Phrase?)

List of Java processes

If I want simply list java processes, use:

ps -A | grep java

JFrame background image

You can do:

setContentPane(new JLabel(new ImageIcon("resources/taverna.jpg")));

At first line of the Jframe class constructor, that works fine for me

Should I check in folder "node_modules" to Git when creating a Node.js app on Heroku?

Explicitly adding a npm version to file package.json ("npm": "1.1.x") and not checking in folder node_modules to Git worked for me.

It may be slower to deploy (since it downloads the packages each time), but I couldn't get the packages to compile when they were checked in. Heroku was looking for files that only existed on my local box.

C++: constructor initializer for arrays

in visual studio 2012 or above, you can do like this

struct Foo { Foo(int x) { /* ... */  } };

struct Baz { 
     Foo foo[3];

     Baz() : foo() { }
};

Is it possible to simulate key press events programmatically?

For those interested, you can, in-fact recreate keyboard input events reliably. In order to change text in input area (move cursors, or the page via an input character) you have to follow the DOM event model closely: http://www.w3.org/TR/DOM-Level-3-Events/#h4_events-inputevents

The model should do:

  • focus (dispatched on the DOM with the target set)

Then for each character:

  • keydown (dispatched on the DOM)
  • beforeinput (dispatched at the target if its a textarea or input)
  • keypress (dispatched on the DOM)
  • input (dispatched at the target if its a textarea or input)
  • change (dispatched at the target if its a select)
  • keyup (dispatched on the DOM)

Then, optionally for most:

  • blur (dispatched on the DOM with the target set)

This actually changes the text in the page via javascript (without modifying value statements) and sets off any javascript listeners/handlers appropriately. If you mess up the sequence javascript will not fire in the appropriate order, the text in the input box will not change, the selections will not change or the cursor will not move to the next space in the text area.

Unfortunately the code was written for an employer under an NDA so I cannot share it, but it is definitely possible but you must recreate the entire key input "stack" for each element in the correct order.

How to read the RGB value of a given pixel in Python?

You can use pygame's surfarray module. This module has a 3d pixel array returning method called pixels3d(surface). I've shown usage below:

from pygame import surfarray, image, display
import pygame
import numpy #important to import

pygame.init()
image = image.load("myimagefile.jpg") #surface to render
resolution = (image.get_width(),image.get_height())
screen = display.set_mode(resolution) #create space for display
screen.blit(image, (0,0)) #superpose image on screen
display.flip()
surfarray.use_arraytype("numpy") #important!
screenpix = surfarray.pixels3d(image) #pixels in 3d array:
#[x][y][rgb]
for y in range(resolution[1]):
    for x in range(resolution[0]):
        for color in range(3):
            screenpix[x][y][color] += 128
            #reverting colors
screen.blit(surfarray.make_surface(screenpix), (0,0)) #superpose on screen
display.flip() #update display
while 1:
    print finished

I hope been helpful. Last word: screen is locked for lifetime of screenpix.

Get element type with jQuery

As Distdev alluded to, you still need to differentiate the input type. That is to say,

$(this).prev().prop('tagName');

will tell you input, but that doesn't differentiate between checkbox/text/radio. If it's an input, you can then use

$('#elementId').attr('type');

to tell you checkbox/text/radio, so you know what kind of control it is.

Working Copy Locked

I fixed it by deleting the hidden .svn folder and replaced it with the fresh checkout .svn and it worked. Probably this hidden folder got messed up!

Regex - Does not contain certain Characters

^[^<>]+$

The caret in the character class ([^) means match anything but, so this means, beginning of string, then one or more of anything except < and >, then the end of the string.

Get the name of a pandas DataFrame

Sometimes df.name doesn't work.

you might get an error message:

'DataFrame' object has no attribute 'name'

try the below function:

def get_df_name(df):
    name =[x for x in globals() if globals()[x] is df][0]
    return name

How to remove focus from input field in jQuery?

Use .blur().

The blur event is sent to an element when it loses focus. Originally, this event was only applicable to form elements, such as <input>. In recent browsers, the domain of the event has been extended to include all element types. An element can lose focus via keyboard commands, such as the Tab key, or by mouse clicks elsewhere on the page.

$("#myInputID").blur(); 

Subclipse svn:ignore

This is just a WAG as I am not a Subclipse user, but have you ensured that the folders containing what you're trying to ignore have themselves been added to SVN? You can't svn:ignore something inside a folder that's not under version control.

LINQ query to select top five

Additional information

Sometimes it is necessary to bind a model into a view models and give a type conversion error. In this situation you should use ToList() method.

var list = (from t in ctn.Items
       where t.DeliverySelection == true && t.Delivery.SentForDelivery == null
       orderby t.Delivery.SubmissionDate
       select t).Take(5).ToList();

How to do date/time comparison

For case when your interval's end it's date without hours like "from 2017-01-01 to whole day of 2017-01-16" it's better to adjust interval's to 23 hours 59 minutes and 59 seconds like:

end = end.Add(time.Duration(23*time.Hour) + time.Duration(59*time.Minute) + time.Duration(59*time.Second)) 

if now.After(start) && now.Before(end) {
    ...
}

Proxy Error 502 : The proxy server received an invalid response from an upstream server

The java application takes too long to respond(maybe due start-up/jvm being cold) thus you get the proxy error.

Proxy Error

The proxy server received an invalid response from an upstream server.
 The proxy server could not handle the request GET /lin/Campaignn.jsp.

As Albert Maclang said amending the http timeout configuration may fix the issue. I suspect the java application throws a 500+ error thus the apache gateway error too. You should look in the logs.

SQL Query for Selecting Multiple Records

You want to add the IN() clause to your WHERE

SELECT * 
FROM `Buses` 
WHERE `BusID` IN (Id1, ID2, ID3,.... put your ids here)

If you have a list of Ids stored in a table you can also do this:

SELECT * 
FROM `Buses` 
WHERE `BusID` IN (SELECT Id FROM table)

How can I tell if a Java integer is null?

parseInt() is just going to throw an exception if the parsing can't complete successfully. You can instead use Integers, the corresponding object type, which makes things a little bit cleaner. So you probably want something closer to:

Integer s = null;

try { 
  s = Integer.valueOf(startField.getText());
}
catch (NumberFormatException e) {
  // ...
}

if (s != null) { ... }

Beware if you do decide to use parseInt()! parseInt() doesn't support good internationalization, so you have to jump through even more hoops:

try {
    NumberFormat nf = NumberFormat.getIntegerInstance(locale);
    nf.setParseIntegerOnly(true);
    nf.setMaximumIntegerDigits(9); // Or whatever you'd like to max out at.

    // Start parsing from the beginning.
    ParsePosition p = new ParsePosition(0);

    int val = format.parse(str, p).intValue();
    if (p.getIndex() != str.length()) {
        // There's some stuff after all the digits are done being processed.
    }

    // Work with the processed value here.
} catch (java.text.ParseFormatException exc) {
    // Something blew up in the parsing.
}

How to create .pfx file from certificate and private key?

You will need to use openssl.

openssl pkcs12 -export -out domain.name.pfx -inkey domain.name.key -in domain.name.crt

The key file is just a text file with your private key in it.

If you have a root CA and intermediate certs, then include them as well using multiple -in params

openssl pkcs12 -export -out domain.name.pfx -inkey domain.name.key -in domain.name.crt -in intermediate.crt -in rootca.crt

You can install openssl from here: openssl

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

My answer might not apply to everyone. Node version: v10.16.0 NPM: 6.9.0

I was having a lot of trouble using node-sass and node-sass-middleware. They are interesting packages because they are widely used (millions of downloads weekly), but their githubs show a limited dependencies and coverage. I was updating an older platform I'd been working on.

What I ended up having to do was:

1) Manually Delete node_modules

2) Manually Delete package-lock.json

3) sudo npm install node-sass --unsafe-perm=true --allow-root

4) sudo npm install node-sass-middleware --unsafe-perm=true --allow-root

I had the following help, thanks!

Pre-built binaries not found for [email protected] and [email protected]

Error: EACCES: permission denied when trying to install ESLint using npm

How to do a non-greedy match in grep?

You're looking for a non-greedy (or lazy) match. To get a non-greedy match in regular expressions you need to use the modifier ? after the quantifier. For example you can change .* to .*?.

By default grep doesn't support non-greedy modifiers, but you can use grep -P to use the Perl syntax.

Submit a form in a popup, and then close the popup

The Solution on top won't work because a submit redirects the page to the endpoint of form and wait for response to redirect. I see that this is an old Question but Most Asked and even i came to know the answer.Still here is my solution what i am implementing. I tried to keep it secure with Nonce but if you don't care then not required.

Method 1: You need to Pop up the form.

document.getElementById('edit_info_button').addEventListener('click',function(){
        window.open('{% url "updateuserinfo" %}','newwindow', 'width=400,height=600,scrollbars=no');
    });

Then you have the form open.

Submit the form normally.

Then return an HTTPResponse in render to a template(HTML file) With a STRICT Content Security Policy. A Variable that contains the following script. Nonce contains a Base64 128bits or larger randomly generated string for every request made to server.

<script nonce="{{nonce}}">window.close()</script>

Method 2:

Or you can redirect to another Page which is suppose to close ... Which already Contains the window.close() script. This will close the pop up window.

Method 3:

Otherwise the simplest will be Use a Ajax call if you are comfortable with one.Use then() and check your condition to the httpresponse from the server.Close the window when success.

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

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

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

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

adding multiple event listeners to one element

//catch volume update
var volEvents = "change,input";
var volEventsArr = volEvents.split(",");
for(var i = 0;i<volknob.length;i++) {
    for(var k=0;k<volEventsArr.length;k++) {
    volknob[i].addEventListener(volEventsArr[k], function() {
        var cfa = document.getElementsByClassName('watch_televised');
        for (var j = 0; j<cfa.length; j++) {
            cfa[j].volume = this.value / 100;
        }
    });
}
}

Get folder up one level

To Whom, deailing with share hosting environment and still chance to have Current PHP less than 7.0 Who does not have dirname( __FILE__, 2 ); it is possible to use following.

function dirname_safe($path, $level = 0){
    $dir = explode(DIRECTORY_SEPARATOR, $path);
    $level = $level * -1;
    if($level == 0) $level = count($dir);
    array_splice($dir, $level);
    return implode($dir, DIRECTORY_SEPARATOR).DIRECTORY_SEPARATOR;
}

print_r(dirname_safe(__DIR__, 2));

Vertical (rotated) text in HTML table

Here is one that works for plain-text with some server side processing:

public string RotateHtmltext(string innerHtml)
{
   const string TRANSFORMTEXT = "transform: rotate(90deg);";
   const string EXTRASTYLECSS = "<style type='text/css'>.r90 {"
                                 + "-webkit-" + TRANSFORMTEXT
                                 + "-moz-" + TRANSFORMTEXT
                                 + "-o-" + TRANSFORMTEXT
                                 + "-ms-" + TRANSFORMTEXT
                                 + "" + TRANSFORMTEXT
                                 + "width:1em;line-height:1ex}</style>";
   const string WRAPPERDIV = "<div style='display: table-cell; vertical-align: middle;'>";

   var newinnerHtml = string.Join("</div>"+WRAPPERDIV, Regex.Split(innerHtml, @"<br */?>").Reverse());

   newinnerHtml = Regex.Replace(newinnerHtml, @"((?:<[^>]*>)|(?:[^<]+))",
                                 match => match.Groups[1].Value.StartsWith("<")
                                             ? match.Groups[1].Value
                                             : string.Join("", match.Groups[1].Value.ToCharArray().Select(x=>"<div class='r90'>"+x+"</div>")),
                                 RegexOptions.Singleline);
   return EXTRASTYLECSS + WRAPPERDIV + newinnerHtml + "</div>";
}

which gives something like:

<style type="text/css">.r90 {
-webkit-transform: rotate(90deg);
-moz-transform: rotate(90deg);
-o-transform: rotate(90deg);
-ms-transform: rotate(90deg);
transform: rotate(90deg);
width: 1em;
line-height: 1ex; 
}</style>
<div style="display: table-cell; vertical-align: middle;">
<div class="r90">p</div>
<div class="r90">o</div>
<div class="r90">s</div>
</div><div style="display: table-cell; vertical-align: middle;">
<div class="r90">(</div>
<div class="r90">A</div>
<div class="r90">b</div>
<div class="r90">s</div>
<div class="r90">)</div>
</div>

http://jsfiddle.net/TzzHy/

onclick open window and specific size

<a style="cursor:pointer"
  onclick=" window.open('http://YOUR.URL.TARGET','',' scrollbars=yes,menubar=no,width=500, resizable=yes,toolbar=no,location=no,status=no')">Your text</a>

jQuery same click event for multiple elements

Add a comma separated list of classes like this :

jQuery(document).ready(function($) {

$('.class, .id').click(function() { 

//  Your code

    }

});

String.Replace ignoring case

Below function is to remove all match word like (this) from the string set. By Ravikant Sonare.

private static void myfun()
{
    string mystring = "thiTHISThiss This THIS THis tThishiThiss. Box";
    var regex = new Regex("this", RegexOptions.IgnoreCase);
    mystring = regex.Replace(mystring, "");
    string[] str = mystring.Split(' ');
    for (int i = 0; i < str.Length; i++)
    {
        if (regex.IsMatch(str[i].ToString()))
        {
            mystring = mystring.Replace(str[i].ToString(), string.Empty);

        }
    }
    Console.WriteLine(mystring);
}

NameError: global name is not defined

You need to do:

import sqlitedbx

def main():
    db = sqlitedbx.SqliteDBzz()
    db.connect()

if __name__ == "__main__":
    main()

How to round a floating point number up to a certain decimal place?

Here is my solution for the round up/down problem

< .5  round down

> = .5  round up

import math

def _should_round_down(val: float):
    if val < 0:
        return ((val * -1) % 1) < 0.5
    return (val % 1) < 0.5

def _round(val: float, ndigits=0):
    if ndigits > 0:
        val *= 10 ** (ndigits - 1)
    is_positive = val > 0
    tmp_val = val
    if not is_positive:
        tmp_val *= -1
    rounded_value = math.floor(tmp_val) if _should_round_down(val) else math.ceil(tmp_val)
    if not is_positive:
        rounded_value *= -1
    if ndigits > 0:
        rounded_value /= 10 ** (ndigits - 1)
    return rounded_value

# test
# nr = 12.2548
# for digit in range(0, 4):
#     print("{} decimals : {} -> {}".format(digit, nr, _round(nr, digit)))

# output
# 0 decimals : 12.2548 -> 12
# 1 decimals : 12.2548 -> 12.0
# 2 decimals : 12.2548 -> 12.3
# 3 decimals : 12.2548 -> 12.25

Android. Fragment getActivity() sometimes returns null

Ok, I know that this question is actually solved but I decided to share my solution for this. I've created abstract parent class for my Fragment:

public abstract class ABaseFragment extends Fragment{

    protected IActivityEnabledListener aeListener;

    protected interface IActivityEnabledListener{
        void onActivityEnabled(FragmentActivity activity);
    }

    protected void getAvailableActivity(IActivityEnabledListener listener){
        if (getActivity() == null){
            aeListener = listener;

        } else {
            listener.onActivityEnabled(getActivity());
        }
    }

    @Override
    public void onAttach(Activity activity) {
        super.onAttach(activity);

        if (aeListener != null){
            aeListener.onActivityEnabled((FragmentActivity) activity);
            aeListener = null;
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);

        if (aeListener != null){
            aeListener.onActivityEnabled((FragmentActivity) context);
            aeListener = null;
        }
    }
}

As you can see, I've added a listener so, whenever I'll need to get Fragments Activity instead of standard getActivity(), I'll need to call

 getAvailableActivity(new IActivityEnabledListener() {
        @Override
        public void onActivityEnabled(FragmentActivity activity) {
            // Do manipulations with your activity
        }
    });

window.open(url, '_blank'); not working on iMac/Safari

window.location.assign(url) this fixs the window.open(url) issue in ios devices

Regular Expression - 2 letters and 2 numbers in C#

You're missing an ending anchor.

if(Regex.IsMatch(myString, "^[A-Za-z]{2}[0-9]{2}\z")) {
    // ...
}

Here's a demo.


EDIT: If you can have anything between an initial 2 letters and a final 2 numbers:

if(Regex.IsMatch(myString, @"^[A-Za-z]{2}.*\d{2}\z")) {
    // ...
}

Here's a demo.