Programs & Examples On #Usleep

usleep is a function provided by various languages and run times that delays a script or program by an amount of time specified in micro-seconds (µ - micro).

Reading and writing to serial port in C on Linux

Some receivers expect EOL sequence, which is typically two characters \r\n, so try in your code replace the line

unsigned char cmd[] = {'I', 'N', 'I', 'T', ' ', '\r', '\0'};

with

unsigned char cmd[] = "INIT\r\n";

BTW, the above way is probably more efficient. There is no need to quote every character.

Xcode Objective-C | iOS: delay function / NSTimer help?

Less code is better code.

[NSThread sleepForTimeInterval:0.06];

Swift:

Thread.sleep(forTimeInterval: 0.06)

Rebuild or regenerate 'ic_launcher.png' from images in Android Studio

On Android Studio 0.5.8 I managed to change my icon set by right clicking on the 'res' folder and selecting New > Image Asset. This brings you to the icon screen you are presented when creating the application, here after you change the icon it confirms that it will replace all the icons. Confirm and done.

How to insert tab character when expandtab option is on in Vim

From the documentation on expandtab:

To insert a real tab when expandtab is on, use CTRL-V<Tab>. See also :retab and ins-expandtab.
This option is reset when the paste option is set and restored when the paste option is reset.

So if you have a mapping for toggling the paste option, e.g.

set pastetoggle=<F2>

you could also do <F2>Tab<F2>.

How do I clear the previous text field value after submitting the form with out refreshing the entire page?

<form>
<input type="text" placeholder="user-name" /><br>
<input type=submit value="submit" id="submit" /> <br>
</form>

<script>
$(window).load(function() {
$('form').children('input:not(#submit)').val('')
}

</script>

You can use this script where every you want.

Assembly code vs Machine code vs Object code?

Machine code is binary (1's and 0's) code that can be executed directly by the CPU. If you open a machine code file in a text editor you would see garbage, including unprintable characters (no, not those unprintable characters ;) ).

Object code is a portion of machine code not yet linked into a complete program. It's the machine code for one particular library or module that will make up the completed product. It may also contain placeholders or offsets not found in the machine code of a completed program. The linker will use these placeholders and offsets to connect everything together.

Assembly code is plain-text and (somewhat) human read-able source code that mostly has a direct 1:1 analog with machine instructions. This is accomplished using mnemonics for the actual instructions, registers, or other resources. Examples include JMP and MULT for the CPU's jump and multiplication instructions. Unlike machine code, the CPU does not understand assembly code. You convert assembly code to machine code with the use of an assembler or a compiler, though we usually think of compilers in association with high-level programming language that are abstracted further from the CPU instructions.


Building a complete program involves writing source code for the program in either assembly or a higher level language like C++. The source code is assembled (for assembly code) or compiled (for higher level languages) to object code, and individual modules are linked together to become the machine code for the final program. In the case of very simple programs the linking step may not be needed. In other cases, such as with an IDE (integrated development environment) the linker and compiler may be invoked together. In other cases, a complicated make script or solution file may be used to tell the environment how to build the final application.

There are also interpreted languages that behave differently. Interpreted languages rely on the machine code of a special interpreter program. At the basic level, an interpreter parses the source code and immediately converts the commands to new machine code and executes them. Modern interpreters are now much more complicated: evaluating whole sections of source code at a time, caching and optimizing where possible, and handling complex memory management tasks.

One final type of program involves the use of a runtime-environment or virtual machine. In this situation, a program is first pre-compiled to a lower-level intermediate language or byte code. The byte code is then loaded by the virtual machine, which just-in-time compiles it to native code. The advantage here is the virtual machine can take advantage of optimizations available at the time the program runs and for that specific environment. A compiler belongs to the developer, and therefore must produce relatively generic (less-optimized) machine code that could run in many places. The runtime environment or virtual machine, however, is located on the end user's computer and therefore can take advantage of all the features provided by that system.

How to use Chrome's network debugger with redirects

Another great solution to debug the Network calls before redirecting to other pages is to select the beforeunload event break point

This way you assure to break the flow right before it redirecting it to another page, this way all network calls, network data and console logs are still there.

This solution is best when you want to check what is the response of the calls

Chrome beforeunload event break point

P.S: You can also use XHR break points if you want to stop right before a specific call or any call (see image example) XHR break point

How to stop console from closing on exit?

Yes, in VS2010 they changed this behavior somewhy.
Open your project and navigate to the following menu: Project -> YourProjectName Properties -> Configuration Properties -> Linker -> System. There in the field SubSystem use the drop-down to select Console (/SUBSYSTEM:CONSOLE) and apply the change.
"Start without debugging" should do the right thing now.

Or, if you write in C++ or in C, put

system("pause");

at the end of your program, then you'll get "Press any key to continue..." even when running in debug mode.

How to expand 'select' option width after the user wants to select an option

I fixed it in my bootstrap page by setting the min-width and max-width to the same value in the select and then setting the select:focus to auto.

_x000D_
_x000D_
select {_x000D_
  min-width: 120px;_x000D_
  max-width: 120px;_x000D_
}_x000D_
select:focus {_x000D_
  width: auto;_x000D_
}
_x000D_
<select style="width: 120px">_x000D_
  <option>REALLY LONG TEXT, REALLY LONG TEXT, REALLY LONG TEXT</option>_x000D_
  <option>ABC</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

What is a tracking branch?

The ProGit book has a very good explanation:

Tracking Branches

Checking out a local branch from a remote branch automatically creates what is called a tracking branch. Tracking branches are local branches that have a direct relationship to a remote branch. If you’re on a tracking branch and type git push, Git automatically knows which server and branch to push to. Also, running git pull while on one of these branches fetches all the remote references and then automatically merges in the corresponding remote branch.

When you clone a repository, it generally automatically creates a master branch that tracks origin/master. That’s why git push and git pull work out of the box with no other arguments. However, you can set up other tracking branches if you wish — ones that don’t track branches on origin and don’t track the master branch. The simple case is the example you just saw, running git checkout -b [branch] [remotename]/[branch]. If you have Git version 1.6.2 or later, you can also use the --track shorthand:

$ git checkout --track origin/serverfix
Branch serverfix set up to track remote branch refs/remotes/origin/serverfix.
Switched to a new branch "serverfix"

To set up a local branch with a different name than the remote branch, you can easily use the first version with a different local branch name:

$ git checkout -b sf origin/serverfix
Branch sf set up to track remote branch refs/remotes/origin/serverfix.
Switched to a new branch "sf"

Now, your local branch sf will automatically push to and pull from origin/serverfix.

BONUS: extra git status info

With a tracking branch, git status will tell you whether how far behind your tracking branch you are - useful to remind you that you haven't pushed your changes yet! It looks like this:

$ git status
On branch master
Your branch is ahead of 'origin/master' by 1 commit.
  (use "git push" to publish your local commits)

or

$ git status
On branch dev
Your branch and 'origin/dev' have diverged,
and have 3 and 1 different commits each, respectively.
  (use "git pull" to merge the remote branch into yours)

How does bitshifting work in Java?

These examples cover the three types of shifts applied to both a positive and a negative number:

// Signed left shift on 626348975
00100101010101010101001110101111 is   626348975
01001010101010101010011101011110 is  1252697950 after << 1
10010101010101010100111010111100 is -1789571396 after << 2
00101010101010101001110101111000 is   715824504 after << 3

// Signed left shift on -552270512
11011111000101010000010101010000 is  -552270512
10111110001010100000101010100000 is -1104541024 after << 1
01111100010101000001010101000000 is  2085885248 after << 2
11111000101010000010101010000000 is  -123196800 after << 3


// Signed right shift on 626348975
00100101010101010101001110101111 is   626348975
00010010101010101010100111010111 is   313174487 after >> 1
00001001010101010101010011101011 is   156587243 after >> 2
00000100101010101010101001110101 is    78293621 after >> 3

// Signed right shift on -552270512
11011111000101010000010101010000 is  -552270512
11101111100010101000001010101000 is  -276135256 after >> 1
11110111110001010100000101010100 is  -138067628 after >> 2
11111011111000101010000010101010 is   -69033814 after >> 3


// Unsigned right shift on 626348975
00100101010101010101001110101111 is   626348975
00010010101010101010100111010111 is   313174487 after >>> 1
00001001010101010101010011101011 is   156587243 after >>> 2
00000100101010101010101001110101 is    78293621 after >>> 3

// Unsigned right shift on -552270512
11011111000101010000010101010000 is  -552270512
01101111100010101000001010101000 is  1871348392 after >>> 1
00110111110001010100000101010100 is   935674196 after >>> 2
00011011111000101010000010101010 is   467837098 after >>> 3

Using atan2 to find angle between two vectors

You don't have to use atan2 to calculate the angle between two vectors. If you just want the quickest way, you can use dot(v1, v2)=|v1|*|v2|*cos A to get

A = Math.acos( dot(v1, v2)/(v1.length()*v2.length()) );

Bash checking if string does not contain other string

As mainframer said, you can use grep, but i would use exit status for testing, try this:

#!/bin/bash
# Test if anotherstring is contained in teststring
teststring="put you string here"
anotherstring="string"

echo ${teststring} | grep --quiet "${anotherstring}"
# Exit status 0 means anotherstring was found
# Exit status 1 means anotherstring was not found

if [ $? = 1 ]
then
  echo "$anotherstring was not found"
fi

Android, How to create option Menu

Change your onCreateOptionsMenu method to return true. To quote the docs:

You must return true for the menu to be displayed; if you return false it will not be shown.

Implicit type conversion rules in C++ operators

The type of the expression, when not both parts are of the same type, will be converted to the biggest of both. The problem here is to understand which one is bigger than the other (it does not have anything to do with size in bytes).

In expressions in which a real number and an integer number are involved, the integer will be promoted to real number. For example, in int + float, the type of the expression is float.

The other difference are related to the capability of the type. For example, an expression involving an int and a long int will result of type long int.

How to get row count using ResultSet in Java?

your sql Statement creating code may be like

statement = connection.createStatement();

To solve "com.microsoft.sqlserver.jdbc.SQLServerException: The requested operation is not supported on forward only result sets" exception change above code with

statement = connection.createStatement(
    ResultSet.TYPE_SCROLL_INSENSITIVE, 
    ResultSet.CONCUR_READ_ONLY);

After above change you can use

int size = 0;
try {
    resultSet.last();
    size = resultSet.getRow();
    resultSet.beforeFirst();
}
catch(Exception ex) {
    return 0;
}
return size;

to get row count

MySQL stored procedure vs function, which would I use when?

A stored function can be used within a query. You could then apply it to every row, or within a WHERE clause.

A procedure is executed using the CALL query.

getElementById returns null?

It can be caused by:

  1. Invalid HTML syntax (some tag is not closed or similar error)
  2. Duplicate IDs - there are two HTML DOM elements with the same ID
  3. Maybe element you are trying to get by ID is created dynamically (loaded by ajax or created by script)?

Please, post your code.

Find a value in an array of objects in Javascript

function getValue(){
    for(var i = 0 ; i< array.length; i++){
        var obj = array[i];
        var arr = array["types"];
        for(var j = 0; j<arr.length;j++ ){
            if(arr[j] == "value"){
                return obj;
            }
        }

    }
}

declaring a priority_queue in c++ with a custom comparator

Answering your question directly:

I'm trying to declare a priority_queue of nodes, using bool Compare(Node a, Node b) as the comparator function

What I currently have is:

priority_queue<Node, vector<Node>, Compare> openSet;

For some reason, I'm getting Error:

"Compare" is not a type name

The compiler is telling you exactly what's wrong: Compare is not a type name, but an instance of a function that takes two Nodes and returns a bool.
What you need is to specify the function pointer type:
std::priority_queue<Node, std::vector<Node>, bool (*)(Node, Node)> openSet(Compare)

What is the difference between '@' and '=' in directive scope in AngularJS?

The = means bi-directional binding, so a reference to a variable to the parent scope. This means, when you change the variable in the directive, it will be changed in the parent scope as well.

@ means the variable will be copied (cloned) into the directive.

As far as I know, <pane bi-title="{{title}}" title="{{title}}">{{text}}</pane> should work too. bi-title will receive the parent scope variable value, which can be changed in the directive.

If you need to change several variables in the parent scope, you could execute a function on the parent scope from within the directive (or pass data via a service).

How to build query string with Javascript

No, I don't think standard JavaScript has that built in, but Prototype JS has that function (surely most other JS frameworks have too, but I don't know them), they call it serialize.

I can reccomend Prototype JS, it works quite okay. The only drawback I've really noticed it it's size (a few hundred kb) and scope (lots of code for ajax, dom, etc.). Thus if you only want a form serializer it's overkill, and strictly speaking if you only want it's Ajax functionality (wich is mainly what I used it for) it's overkill. Unless you're careful you may find that it does a little too much "magic" (like extending every dom element it touches with Prototype JS functions just to find elements) making it slow on extreme cases.

Objective-C: Extract filename from path string

If you're displaying a user-readable file name, you do not want to use lastPathComponent. Instead, pass the full path to NSFileManager's displayNameAtPath: method. This basically does does the same thing, only it correctly localizes the file name and removes the extension based on the user's preferences.

Android Studio rendering problems

Best Solution is go to File -> Sync Project With Gradle Files

I hope this helped

If using maven, usually you put log4j.properties under java or resources?

Just putting it in src/main/resources will bundle it inside the artifact. E.g. if your artifact is a JAR, you will have the log4j.properties file inside it, losing its initial point of making logging configurable.

I usually put it in src/main/resources, and set it to be output to target like so:

<build>
    <resources>
        <resource>
            <directory>src/main/resources</directory>
            <targetPath>${project.build.directory}</targetPath>
            <includes>
                <include>log4j.properties</include>
            </includes>
        </resource>
    </resources>
</build>

Additionally, in order for log4j to actually see it, you have to add the output directory to the class path. If your artifact is an executable JAR, you probably used the maven-assembly-plugin to create it. Inside that plugin, you can add the current folder of the JAR to the class path by adding a Class-Path manifest entry like so:

<plugin>
    <artifactId>maven-assembly-plugin</artifactId>
    <configuration>
        <archive>
            <manifest>
                <mainClass>com.your-package.Main</mainClass>
            </manifest>
            <manifestEntries>
                <Class-Path>.</Class-Path>
            </manifestEntries>
        </archive>
        <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
        </descriptorRefs>
    </configuration>
    <executions>
        <execution>
            <id>make-assembly</id> <!-- this is used for inheritance merges -->
            <phase>package</phase> <!-- bind to the packaging phase -->
            <goals>
                <goal>single</goal>
            </goals>
        </execution>
    </executions>
</plugin>

Now the log4j.properties file will be right next to your JAR file, independently configurable.

To run your application directly from Eclipse, add the resources directory to your classpath in your run configuration: Run->Run Configurations...->Java Application->New select the Classpath tab, select Advanced and browse to your src/resources directory.

Using comma as list separator with AngularJS

Also:

angular.module('App.filters', [])
    .filter('joinBy', function () {
        return function (input,delimiter) {
            return (input || []).join(delimiter || ',');
        };
    });

And in template:

{{ itemsArray | joinBy:',' }}

Why doesn't java.io.File have a close method?

java.io.File doesn't represent an open file, it represents a path in the filesystem. Therefore having close method on it doesn't make sense.

Actually, this class was misnamed by the library authors, it should be called something like Path.

Checking whether the pip is installed?

You need to run pip list in bash not in python.

pip list
DEPRECATION: Python 2.6 is no longer supported by the Python core team, please upgrade your Python. A future version of pip will drop support for Python 2.6
argparse (1.4.0)
Beaker (1.3.1)
cas (0.15)
cups (1.0)
cupshelpers (1.0)
decorator (3.0.1)
distribute (0.6.10)
---and other modules

What tool can decompile a DLL into C++ source code?

There are no decompilers which I know about. W32dasm is good Win32 disassembler.

How to delete columns in numpy.array

Example from the numpy documentation:

>>> a = numpy.array([[ 0,  1,  2,  3],
               [ 4,  5,  6,  7],
               [ 8,  9, 10, 11],
               [12, 13, 14, 15]])

>>> numpy.delete(a, numpy.s_[1:3], axis=0)                       # remove rows 1 and 2

array([[ 0,  1,  2,  3],
       [12, 13, 14, 15]])

>>> numpy.delete(a, numpy.s_[1:3], axis=1)                       # remove columns 1 and 2

array([[ 0,  3],
       [ 4,  7],
       [ 8, 11],
       [12, 15]])

key_load_public: invalid format

As Roland mentioned in their answer, it's a warning that the ssh-agent doesn't understand the format of the public key and even then, the public key will not be used locally.

However, I can also elaborate and answer why the warning is there. It simply boils down to the fact that the PuTTY Key Generator generates two different public key formats depending on what you do in the program.

Note: Throughout my explanation, the key files I will be using/generating will be named id_rsa with their appropriate extensions. Furthermore, for copy-paste convenience, the parent folder of the keys will be assumed to be ~/.ssh/. Adjust these details to suit your needs as desired.

The Formats

Link to the relevant PuTTY documentation

SSH-2

When you save a key using the PuTTY Key Generator using the "Save public key" button, it will be saved in the format defined by RFC 4716.

Example:

---- BEGIN SSH2 PUBLIC KEY ----
Comment: "github-example-key"
AAAAB3NzaC1yc2EAAAABJQAAAQEAhl/CNy9wI1GVdiHAJQV0CkHnMEqW7+Si9WYF
i2fSBrsGcmqeb5EwgnhmTcPgtM5ptGBjUZR84nxjZ8SPmnLDiDyHDPIsmwLBHxcp
pY0fhRSGtWL5fT8DGm9EfXaO1QN8c31VU/IkD8niWA6NmHNE1qEqpph3DznVzIm3
oMrongEjGw7sDP48ZTZp2saYVAKEEuGC1YYcQ1g20yESzo7aP70ZeHmQqI9nTyEA
ip3mL20+qHNsHfW8hJAchaUN8CwNQABJaOozYijiIUgdbtSTMRDYPi7fjhgB3bA9
tBjh7cOyuU/c4M4D6o2mAVYdLAWMBkSoLG8Oel6TCcfpO/nElw==
---- END SSH2 PUBLIC KEY ----

OpenSSH

Contrary to popular belief, this format doesn't get saved by the generator. However it is generated and shown in the text box titled "Public key for pasting into OpenSSH authorized_keys file". To save it as a file, you have to manually copy it from the text box and paste it into a new text file.

For the key shown above, this would be:

ssh-rsa AAAAB3NzaC1yc2EAAAABJQAAAQEAhl/CNy9wI1GVdiHAJQV0CkHnMEqW7+Si9WYFi2fSBrsGcmqeb5EwgnhmTcPgtM5ptGBjUZR84nxjZ8SPmnLDiDyHDPIsmwLBHxcppY0fhRSGtWL5fT8DGm9EfXaO1QN8c31VU/IkD8niWA6NmHNE1qEqpph3DznVzIm3oMrongEjGw7sDP48ZTZp2saYVAKEEuGC1YYcQ1g20yESzo7aP70ZeHmQqI9nTyEAip3mL20+qHNsHfW8hJAchaUN8CwNQABJaOozYijiIUgdbtSTMRDYPi7fjhgB3bA9tBjh7cOyuU/c4M4D6o2mAVYdLAWMBkSoLG8Oel6TCcfpO/nElw== github-example-key

The format of the key is simply ssh-rsa <signature> <comment> and can be created by rearranging the SSH-2 formatted file.

Regenerating Public Keys

If you are making use of ssh-agent, you will likely also have access to ssh-keygen.

If you have your OpenSSH Private Key (id_rsa file), you can generate the OpenSSH Public Key File using:

ssh-keygen -f ~/.ssh/id_rsa -y > ~/.ssh/id_rsa.pub

If you only have the PUTTY Private Key (id_rsa.ppk file), you will need to convert it first.

  1. Open the PuTTY Key Generator
  2. On the menu bar, click "File" > "Load private key"
  3. Select your id_rsa.ppk file
  4. On the menu bar, click "Conversions" > "Export OpenSSH key"
  5. Save the file as id_rsa (without an extension)

Now that you have an OpenSSH Private Key, you can use the ssh-keygen tool as above to perform manipulations on the key.

Bonus: The PKCS#1 PEM-encoded Public Key Format

To be honest, I don't know what this key is used for as I haven't needed it. But I have it in my notes I've collated over the years and I'll include it here for wholesome goodness. The file will look like this:

-----BEGIN RSA PUBLIC KEY-----
MIIBCAKCAQEAhl/CNy9wI1GVdiHAJQV0CkHnMEqW7+Si9WYFi2fSBrsGcmqeb5Ew
gnhmTcPgtM5ptGBjUZR84nxjZ8SPmnLDiDyHDPIsmwLBHxcppY0fhRSGtWL5fT8D
Gm9EfXaO1QN8c31VU/IkD8niWA6NmHNE1qEqpph3DznVzIm3oMrongEjGw7sDP48
ZTZp2saYVAKEEuGC1YYcQ1g20yESzo7aP70ZeHmQqI9nTyEAip3mL20+qHNsHfW8
hJAchaUN8CwNQABJaOozYijiIUgdbtSTMRDYPi7fjhgB3bA9tBjh7cOyuU/c4M4D
6o2mAVYdLAWMBkSoLG8Oel6TCcfpO/nElwIBJQ==
-----END RSA PUBLIC KEY-----

This file can be generated using an OpenSSH Private Key (as generated in "Regenerating Public Keys" above) using:

ssh-keygen -f ~/.ssh/id_rsa -y -e -m pem > ~/.ssh/id_rsa.pem

Alternatively, you can use an OpenSSH Public Key using:

ssh-keygen -f ~/.ssh/id_rsa.pub -e -m pem > ~/.ssh/id_rsa.pem

References:

Grouping switch statement cases together?

Sure you can.

You can use case x ... y for the range

Example:

#include <iostream.h>
#include <stdio.h>
int main()
{
   int Answer;
   cout << "How many cars do you have?";
   cin >> Answer;
   switch (Answer)                                      
      {
      case 1 ... 4:
         cout << "You need more cars. ";
         break;                                        
      case 5 ... 8:
         cout << "Now you need a house. ";
         break;                                        
      default:
         cout << "What are you? A peace-loving hippie freak? ";
      }
      cout << "\nPress ENTER to continue... " << endl;
      getchar();
      return 0;
}

Make sure you have "-std=c++0x" flag enabled within your compiler

CLEAR SCREEN - Oracle SQL Developer shortcut?

Use cl scr on the Sql* command line tool to clear all the matter on the screen.

Uncaught syntaxerror: unexpected identifier?

There are errors here :

var formTag = document.getElementsByTagName("form"), // form tag is an array
selectListItem = $('select'),
makeSelect = document.createElement('select'),
makeSelect.setAttribute("id", "groups");

The code must change to:

var formTag = document.getElementsByTagName("form");
var selectListItem = $('select');
var makeSelect = document.createElement('select');
makeSelect.setAttribute("id", "groups");

By the way, there is another error at line 129 :

var createLi.appendChild(createSubList);

Replace it with:

createLi.appendChild(createSubList);

How do I force git to checkout the master branch and remove carriage returns after I've normalized files using the "text" attribute?

As others have pointed out one could just delete all the files in the repo and then check them out. I prefer this method and it can be done with the code below

git ls-files -z | xargs -0 rm
git checkout -- .

or one line

git ls-files -z | xargs -0 rm ; git checkout -- .

I use it all the time and haven't found any down sides yet!

For some further explanation, the -z appends a null character onto the end of each entry output by ls-files, and the -0 tells xargs to delimit the output it was receiving by those null characters.

How to change css property using javascript

You can use style property for this. For example, if you want to change border -

document.elm.style.border = "3px solid #FF0000";

similarly for color -

 document.getElementById("p2").style.color="blue";

Best thing is you define a class and do this -

document.getElementById("p2").className = "classname";

(Cross Browser artifacts must be considered accordingly).

How to insert close button in popover for Bootstrap

$(function(){ 
  $("#example").popover({
    placement: 'bottom',
    html: 'true',
    title : '<span class="text-info"><strong>title!!</strong></span> <button type="button" id="close" class="close">&times;</button></span>',
    content : 'test'
  })

  $(document).on('click', '#close', function (evente) {
    $("#example").popover('hide');
  });
  $("#close").click(function(event) {
    $("#example").popover('hide');
  });
});

<button type="button" id="example" class="btn btn-primary" >click</button>

.htaccess 301 redirect of single page

If you prefer to use the simplest possible solution to a problem, an alternative to RedirectMatch is, the more basic, Redirect directive.

It does not use pattern matching and so is more explicit and easier for others to understand.

i.e

<IfModule mod_alias.c>

#Repoint old contact page to new contact page:
Redirect 301 /contact.php http://example.com/contact-us.php

</IfModule>

Query strings should be carried over because the docs say:

Additional path information beyond the matched URL-path will be appended to the target URL.

Regular expression for exact match of a string

if you have a the input password in a variable and you want to match exactly 123456 then anchors will help you:

/^123456$/

in perl the test for matching the password would be something like

print "MATCH_OK" if ($input_pass=~/^123456$/);

EDIT:

bart kiers is right tho, why don't you use a strcmp() for this? every language has it in its own way

as a second thought, you may want to consider a safer authentication mechanism :)

In laymans terms, what does 'static' mean in Java?

static means that the variable or method marked as such is available at the class level. In other words, you don't need to create an instance of the class to access it.

public class Foo {
    public static void doStuff(){
        // does stuff
    }
}

So, instead of creating an instance of Foo and then calling doStuff like this:

Foo f = new Foo();
f.doStuff();

You just call the method directly against the class, like so:

Foo.doStuff();

How to check if command line tools is installed

I think the simplest way which worked for me to find Command line tools is installed or not and its version irrespective of what macOS version is

$brew config

macOS: 10.14.2-x86_64
CLT: 10.1.0.0.1.1539992718
Xcode: 10.1

This when you have Command Line tools properly installed and paths set properly.

Earlier i got output as below
macOS: 10.14.2-x86_64
CLT: N/A
Xcode: 10.1

CLT was shown as N/A in spite of having gcc and make working fine and below outputs

$xcode-select -p              
/Applications/Xcode.app/Contents/Developer
$pkgutil --pkg-info=com.apple.pkg.CLTools_Executables
No receipt for 'com.apple.pkg.CLTools_Executables' found at '/'.
$brew doctor
Your system is ready to brew.

Finally doing xcode-select --install resolved my issue of brew unable to find CLT for installing packages as below.

Installing sphinx-doc dependency: python
Warning: Building python from source:
  The bottle needs the Apple Command Line Tools to be installed.
  You can install them, if desired, with:
    xcode-select --install

find vs find_by vs where

The best part of working with any open source technology is that you can inspect length and breadth of it. Checkout this link

find_by ~> Finds the first record matching the specified conditions. There is no implied ordering so if order matters, you should specify it yourself. If no record is found, returns nil.

find ~> Finds the first record matching the specified conditions , but if no record is found, it raises an exception but that is done deliberately.

Do checkout the above link, it has all the explanation and use cases for the following two functions.

PowerShell on Windows 7: Set-ExecutionPolicy for regular users

This should solve your problem, you should try to run the following below:

Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser 

Converting a datetime string to timestamp in Javascript

Parsing dates is a pain in JavaScript as there's no extensive native support. However you could do something like the following by relying on the Date(year, month, day [, hour, minute, second, millisecond]) constructor signature of the Date object.

var dateString = '17-09-2013 10:08',
    dateTimeParts = dateString.split(' '),
    timeParts = dateTimeParts[1].split(':'),
    dateParts = dateTimeParts[0].split('-'),
    date;

date = new Date(dateParts[2], parseInt(dateParts[1], 10) - 1, dateParts[0], timeParts[0], timeParts[1]);

console.log(date.getTime()); //1379426880000
console.log(date); //Tue Sep 17 2013 10:08:00 GMT-0400

You could also use a regular expression with capturing groups to parse the date string in one line.

var dateParts = '17-09-2013 10:08'.match(/(\d+)-(\d+)-(\d+) (\d+):(\d+)/);

console.log(dateParts); // ["17-09-2013 10:08", "17", "09", "2013", "10", "08"]

Infinity symbol with HTML

According to this page, it's &infin;.

How do I tell CMake to link in a static library in the source directory?

I found this helpful...

http://www.cmake.org/pipermail/cmake/2011-June/045222.html

From their example:

ADD_LIBRARY(boost_unit_test_framework STATIC IMPORTED)
SET_TARGET_PROPERTIES(boost_unit_test_framework PROPERTIES IMPORTED_LOCATION /usr/lib/libboost_unit_test_framework.a)
TARGET_LINK_LIBRARIES(mytarget A boost_unit_test_framework C)

Can I configure a subdomain to point to a specific port on my server

With only 1 IP you can forget DNS but you can use a MineProxy because the handshake packet of the client contains the host that then he connected to and a MineProxy will ready this host and proxy the connection to a server that is registered for that host

Assign a class name to <img> tag instead of write it in css file?

I think the Class on img tag is better when You use the same style in different structure on Your site. You have to decide when you write less line of CSS code and HTML is more readable.

How to center a View inside of an Android Layout?

Step #1: Wrap whatever it is you want centered on the screen in a full-screen RelativeLayout.

Step #2: Give that child view (the one, which you want centered inside the RelativeLayout) the android:layout_centerInParent="true" attribute.

What does Java option -Xmx stand for?

-Xmx sets the Maximum Heap size

Text in Border CSS HTML

Yes, but it's not a div, it's a fieldset

_x000D_
_x000D_
fieldset {
    border: 1px solid #000;
}
_x000D_
<fieldset>
  <legend>AAA</legend>
</fieldset>
_x000D_
_x000D_
_x000D_

Cocoa Touch: How To Change UIView's Border Color And Thickness?

If you didn't want to edit the layer of a UIView, you could always embed the view within another view. The parent view would have its background color set to the border color. It would also be slightly larger, depending upon how wide you want the border to be.

Of course, this only works if your view isn't transparent and you only want a single border color. The OP wanted the border in the view itself, but this may be a viable alternative.

Hide Command Window of .BAT file that Executes Another .EXE File

Using start works fine, unless you are using a scripting language. Fortunately, there's a way out for Python - just use pythonw.exe instead of python.exe:

:: Title not needed:
start pythonw.exe application.py

In case you need quotes, do this:

:: Title needed
start "Great Python App" pythonw.exe "C:\Program Files\Vendor\App\application.py"

Angular 2 Routing run in new tab

Late to this one, but I just discovered an alternative way of doing it:

On your template,

<a (click)="navigateAssociates()">Associates</a> 

And on your component.ts, you can use serializeUrl to convert the route into a string, which can be used with window.open()

navigateAssociates() {
  const url = this.router.serializeUrl(
    this.router.createUrlTree(['/page1'])
  );

  window.open(url, '_blank');
}

How to fill OpenCV image with one solid color?

For an 8-bit (CV_8U) OpenCV image, the syntax is:

Mat img(Mat(nHeight, nWidth, CV_8U);
img = cv::Scalar(50);    // or the desired uint8_t value from 0-255

How to present a simple alert message in java?

Assuming you already have a JFrame to call this from:

JOptionPane.showMessageDialog(frame, "thank you for using java");

See The Java Tutorials: How to Make Dialogs
See the JavaDoc

RestClientException: Could not extract response. no suitable HttpMessageConverter found

In my case it was caused by the absence of the jackson-core, jackson-annotations and jackson-databind jars from the runtime classpath. It did not complain with the usual ClassNothFoundException as one would expect but rather with the error mentioned in the original question.

'and' (boolean) vs '&' (bitwise) - Why difference in behavior with lists vs numpy arrays?

  1. In Python an expression of X and Y returns Y, given that bool(X) == True or any of X or Y evaluate to False, e.g.:

    True and 20 
    >>> 20
    
    False and 20
    >>> False
    
    20 and []
    >>> []
    
  2. Bitwise operator is simply not defined for lists. But it is defined for integers - operating over the binary representation of the numbers. Consider 16 (01000) and 31 (11111):

    16 & 31
    >>> 16
    
  3. NumPy is not a psychic, it does not know, whether you mean that e.g. [False, False] should be equal to True in a logical expression. In this it overrides a standard Python behaviour, which is: "Any empty collection with len(collection) == 0 is False".

  4. Probably an expected behaviour of NumPy's arrays's & operator.

input[type='text'] CSS selector does not apply to default-type text inputs?

try this

 input[type='text']
 {
   background:red !important;
 }

Less aggressive compilation with CSS3 calc

There is several escaping options with same result:

body { width: ~"calc(100% - 250px - 1.5em)"; }
body { width: calc(~"100% - 250px - 1.5em"); }
body { width: calc(100% ~"-" 250px ~"-" 1.5em); }

Center/Set Zoom of Map to cover all visible Markers?

There is this MarkerClusterer client side utility available for google Map as specified here on Google Map developer Articles, here is brief on what's it's usage:

There are many approaches for doing what you asked for:

  • Grid based clustering
  • Distance based clustering
  • Viewport Marker Management
  • Fusion Tables
  • Marker Clusterer
  • MarkerManager

You can read about them on the provided link above.

Marker Clusterer uses Grid Based Clustering to cluster all the marker wishing the grid. Grid-based clustering works by dividing the map into squares of a certain size (the size changes at each zoom) and then grouping the markers into each grid square.

Before Clustering Before Clustering

After Clustering After Clustering

I hope this is what you were looking for & this will solve your problem :)

What's the difference between TRUNCATE and DELETE in SQL

DELETE

DELETE is a DML command
DELETE you can rollback
Delete = Only Delete- so it can be rolled back
In DELETE you can write conditions using WHERE clause
Syntax – Delete from [Table] where [Condition]

TRUNCATE

TRUNCATE is a DDL command
You can't rollback in TRUNCATE, TRUNCATE removes the record permanently
Truncate = Delete+Commit -so we can't roll back
You can't use conditions(WHERE clause) in TRUNCATE
Syntax – Truncate table [Table]

For more details visit

http://www.zilckh.com/what-is-the-difference-between-truncate-and-delete/

How can I show an image using the ImageView component in javafx and fxml?

src/sample/images/shopp.png

**
    Parent root =new StackPane();
    ImageView imageView=new ImageView(new Image(getClass().getResourceAsStream("images/shopp.png")));
    ((StackPane) root).getChildren().add(imageView);

**

How to do multiline shell script in Ansible

Ansible uses YAML syntax in its playbooks. YAML has a number of block operators:

  • The > is a folding block operator. That is, it joins multiple lines together by spaces. The following syntax:

    key: >
      This text
      has multiple
      lines
    

    Would assign the value This text has multiple lines\n to key.

  • The | character is a literal block operator. This is probably what you want for multi-line shell scripts. The following syntax:

    key: |
      This text
      has multiple
      lines
    

    Would assign the value This text\nhas multiple\nlines\n to key.

You can use this for multiline shell scripts like this:

- name: iterate user groups
  shell: |
    groupmod -o -g {{ item['guid'] }} {{ item['username'] }} 
    do_some_stuff_here
    and_some_other_stuff
  with_items: "{{ users }}"

There is one caveat: Ansible does some janky manipulation of arguments to the shell command, so while the above will generally work as expected, the following won't:

- shell: |
    cat <<EOF
    This is a test.
    EOF

Ansible will actually render that text with leading spaces, which means the shell will never find the string EOF at the beginning of a line. You can avoid Ansible's unhelpful heuristics by using the cmd parameter like this:

- shell:
    cmd: |
      cat <<EOF
      This is a test.
      EOF

"unadd" a file to svn before commit

svn rm --keep-local folder_name

Note: In svn 1.5.4 svn rm deletes unversioned files even when --keep-local is specified. See http://svn.haxx.se/users/archive-2009-11/0058.shtml for more information.

Differences Between vbLf, vbCrLf & vbCr Constants

The three constants have similar functions nowadays, but different historical origins, and very occasionally you may be required to use one or the other.

You need to think back to the days of old manual typewriters to get the origins of this. There are two distinct actions needed to start a new line of text:

  1. move the typing head back to the left. In practice in a typewriter this is done by moving the roll which carries the paper (the "carriage") all the way back to the right -- the typing head is fixed. This is a carriage return.
  2. move the paper up by the width of one line. This is a line feed.

In computers, these two actions are represented by two different characters - carriage return is CR, ASCII character 13, vbCr; line feed is LF, ASCII character 10, vbLf. In the old days of teletypes and line printers, the printer needed to be sent these two characters -- traditionally in the sequence CRLF -- to start a new line, and so the CRLF combination -- vbCrLf -- became a traditional line ending sequence, in some computing environments.

The problem was, of course, that it made just as much sense to only use one character to mark the line ending, and have the terminal or printer perform both the carriage return and line feed actions automatically. And so before you knew it, we had 3 different valid line endings: LF alone (used in Unix and Macintoshes), CR alone (apparently used in older Mac OSes) and the CRLF combination (used in DOS, and hence in Windows). This in turn led to the complications of DOS / Windows programs having the option of opening files in text mode, where any CRLF pair read from the file was converted to a single CR (and vice versa when writing).

So - to cut a (much too) long story short - there are historical reasons for the existence of the three separate line separators, which are now often irrelevant: and perhaps the best course of action in .NET is to use Environment.NewLine which means someone else has decided for you which to use, and future portability issues should be reduced.

Generate C# class from XML

To convert XML into a C# Class:

  • Navigate to the Microsoft Visual Studio Marketplace: -- https://marketplace.visualstudio.com
  • In the search bar enter text: -- xml to class code tool
  • Download, install, and use the app

Note: in the fullness of time, this app may be replaced, but chances are, there'll be another tool that does the same thing.

How to make a div fill a remaining horizontal space?

This seems to accomplish what you're going for.

_x000D_
_x000D_
#left {_x000D_
  float:left;_x000D_
  width:180px;_x000D_
  background-color:#ff0000;_x000D_
}_x000D_
#right {_x000D_
  width: 100%;_x000D_
  background-color:#00FF00;_x000D_
}
_x000D_
<div>_x000D_
  <div id="left">_x000D_
    left_x000D_
  </div>_x000D_
  <div id="right">_x000D_
    right_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Android Studio - How to Change Android SDK Path

This is how its done,in Android Studio for windows First got to Project Structure

Then to sdk location tab

From there select android sdk location and select your sdk path and then click on OK button

Done

one line if statement in php

Something like this?

($var > 2 ? echo "greater" : echo "smaller")

Why is it bad practice to call System.gc()?

  1. Since objects are dynamically allocated by using the new operator,
    you might be wondering how such objects are destroyed and their
    memory released for later reallocation.

  2. In some languages, such as C++, dynamically allocated objects must be manually released by use of a delete operator.

  3. Java takes a different approach; it handles deallocation for you automatically.
  4. The technique that accomplishes this is called garbage collection. It works like this: when no references to an object exist, that object is assumed to be no longer needed, and the memory occupied by the object can be reclaimed. There is no explicit need to destroy objects as in C++.
  5. Garbage collection only occurs sporadically (if at all) during the execution of your program.
  6. It will not occur simply because one or more objects exist that are no longer used.
  7. Furthermore, different Java run-time implementations will take varying approaches to garbage collection, but for the most part, you should not have to think about it while writing your programs.

I want to calculate the distance between two points in Java

This may be OLD, but here is the best answer:

    float dist = (float) Math.sqrt(
            Math.pow(x1 - x2, 2) +
            Math.pow(y1 - y2, 2) );

Mean of a column in a data frame, given the column's name

Use summarise in the dplyr package:

library(dplyr)
summarise(df, Average = mean(col_name, na.rm = T))

note: dplyr supports both summarise and summarize.

Aligning rotated xticklabels with their respective xticks

An easy, loop-free alternative is to use the horizontalalignment Text property as a keyword argument to xticks[1]. In the below, at the commented line, I've forced the xticks alignment to be "right".

n=5
x = np.arange(n)
y = np.sin(np.linspace(-3,3,n))
xlabels = ['Long ticklabel %i' % i for i in range(n)]
fig, ax = plt.subplots()
ax.plot(x,y, 'o-')

plt.xticks(
        [0,1,2,3,4],
        ["this label extends way past the figure's left boundary",
        "bad motorfinger", "green", "in the age of octopus diplomacy", "x"], 
        rotation=45,
        horizontalalignment="right")    # here
plt.show()

(yticks already aligns the right edge with the tick by default, but for xticks the default appears to be "center".)

[1] You find that described in the xticks documentation if you search for the phrase "Text properties".

How to exit if a command failed?

You can also use, if you want to preserve exit error status, and have a readable file with one command per line:

my_command1 || exit $?
my_command2 || exit $?

This, however will not print any additional error message. But in some cases, the error will be printed by the failed command anyway.

How can I show dots ("...") in a span with hidden overflow?

I think you are looking for text-overflow: ellipsis in combination with white-space: nowrap

See some more details here

In PHP, how can I add an object element to an array?

Something like:

class TestClass {
private $var1;
private $var2;

private function TestClass($var1, $var2){
    $this->var1 = $var1;
    $this->var2 = $var2;
}

public static function create($var1, $var2){
    if (is_numeric($var1)){
        return new TestClass($var1, $var2);
    }
    else return NULL;
}
}

$myArray = array();
$myArray[] = TestClass::create(15, "asdf");
$myArray[] = TestClass::create(20, "asdfa");
$myArray[] = TestClass::create("a", "abcd");

print_r($myArray);

$myArray = array_filter($myArray, function($e){ return !is_null($e);});

print_r($myArray);

I think that there are situations where this constructions are preferable to arrays. You can move all the checking logic to the class.

Here, before the call to array_filter $myArray has 3 elements. Two correct objects and a NULL. After the call, only the 2 correct elements persist.

ModuleNotFoundError: What does it mean __main__ is not a package?

Simply remove the dot for the relative import and do:

from p_02_paying_debt_off_in_a_year import compute_balance_after

Android charting libraries

  • Achartengine: I have used this. Although for real time graph this might not give good performance if you do not tweak properly.

Configure Nginx with proxy_pass

Nginx prefers prefix-based location matches (not involving regular expression), that's why in your code block, /stash redirects are going to /.

The algorithm used by Nginx to select which location to use is described thoroughly here: https://www.digitalocean.com/community/tutorials/understanding-nginx-server-and-location-block-selection-algorithms#matching-location-blocks

How to run multiple Python versions on Windows

Running a different copy of Python is as easy as starting the correct executable. You mention that you've started a python instance, from the command line, by simply typing python.

What this does under Windows, is to trawl the %PATH% environment variable, checking for an executable, either batch file (.bat), command file (.cmd) or some other executable to run (this is controlled by the PATHEXT environment variable), that matches the name given. When it finds the correct file to run the file is being run.

Now, if you've installed two python versions 2.5 and 2.6, the path will have both of their directories in it, something like PATH=c:\python\2.5;c:\python\2.6 but Windows will stop examining the path when it finds a match.

What you really need to do is to explicitly call one or both of the applications, such as c:\python\2.5\python.exe or c:\python\2.6\python.exe.

The other alternative is to create a shortcut to the respective python.exe calling one of them python25 and the other python26; you can then simply run python25 on your command line.

Get values from an object in JavaScript

In ES2017 you can use Object.values():

Object.values(data)

At the time of writing support is limited (FireFox and Chrome).All major browsers except IE support this now.

In ES2015 you can use this:

Object.keys(data).map(k => data[k])

How would I get everything before a : in a string Python

Using index:

>>> string = "Username: How are you today?"
>>> string[:string.index(":")]
'Username'

The index will give you the position of : in string, then you can slice it.

If you want to use regex:

>>> import re
>>> re.match("(.*?):",string).group()
'Username'                       

match matches from the start of the string.

you can also use itertools.takewhile

>>> import itertools
>>> "".join(itertools.takewhile(lambda x: x!=":", string))
'Username'

Carriage Return\Line feed in Java

bw.newLine(); cannot ensure compatibility with all systems.

If you are sure it is going to be opened in windows, you can format it to windows newline.

If you are already using native unix commands, try unix2dos and convert teh already generated file to windows format and then send the mail.

If you are not using unix commands and prefer to do it in java, use ``bw.write("\r\n")` and if it does not complicate your program, have a method that finds out the operating system and writes the appropriate newline.

How to write a multidimensional array to a text file?

ndarray.tofile() should also work

e.g. if your array is called a:

a.tofile('yourfile.txt',sep=" ",format="%s")

Not sure how to get newline formatting though.

Edit (credit Kevin J. Black's comment here):

Since version 1.5.0, np.tofile() takes an optional parameter newline='\n' to allow multi-line output. https://docs.scipy.org/doc/numpy-1.13.0/reference/generated/numpy.savetxt.html

How to ping a server only once from within a batch file?

I am sure you must have named the resultant bat file as "ping.bat". If you rename your file to something else say pingXXX.bat. It will definitely work. Try it out.

my batch file contains below code only

ping 172.31.29.1 -t

with file name as ping.bat enter image description here

with file name abc.bat

enter image description here

Rotating a Div Element in jQuery

Cross-browser rotate for any element. Works in IE7 and IE8. In IE7 it looks like not working in JSFiddle but in my project worked also in IE7

http://jsfiddle.net/RgX86/24/

var elementToRotate = $('#rotateMe');
var degreeOfRotation = 33;

var deg = degreeOfRotation;
var deg2radians = Math.PI * 2 / 360;
var rad = deg * deg2radians ;
var costheta = Math.cos(rad);
var sintheta = Math.sin(rad);

var m11 = costheta;
var m12 = -sintheta;
var m21 = sintheta;
var m22 = costheta;
var matrixValues = 'M11=' + m11 + ', M12='+ m12 +', M21='+ m21 +', M22='+ m22;

elementToRotate.css('-webkit-transform','rotate('+deg+'deg)')
    .css('-moz-transform','rotate('+deg+'deg)')
    .css('-ms-transform','rotate('+deg+'deg)')
    .css('transform','rotate('+deg+'deg)')
    .css('filter', 'progid:DXImageTransform.Microsoft.Matrix(sizingMethod=\'auto expand\','+matrixValues+')')
    .css('-ms-filter', 'progid:DXImageTransform.Microsoft.Matrix(SizingMethod=\'auto expand\','+matrixValues+')');

Edit 13/09/13 15:00 Wrapped in a nice and easy, chainable, jquery plugin.

Example of use

$.fn.rotateElement = function(angle) {
    var elementToRotate = this,
        deg = angle,
        deg2radians = Math.PI * 2 / 360,
        rad = deg * deg2radians ,
        costheta = Math.cos(rad),
        sintheta = Math.sin(rad),

        m11 = costheta,
        m12 = -sintheta,
        m21 = sintheta,
        m22 = costheta,
        matrixValues = 'M11=' + m11 + ', M12='+ m12 +', M21='+ m21 +', M22='+ m22;

    elementToRotate.css('-webkit-transform','rotate('+deg+'deg)')
        .css('-moz-transform','rotate('+deg+'deg)')
        .css('-ms-transform','rotate('+deg+'deg)')
        .css('transform','rotate('+deg+'deg)')
        .css('filter', 'progid:DXImageTransform.Microsoft.Matrix(sizingMethod=\'auto expand\','+matrixValues+')')
        .css('-ms-filter', 'progid:DXImageTransform.Microsoft.Matrix(SizingMethod=\'auto expand\','+matrixValues+')');
    return elementToRotate;
}

$element.rotateElement(15);

JSFiddle: http://jsfiddle.net/RgX86/175/

How to list all installed packages and their versions in Python?

My take:

#!/usr/bin/env python3

import pkg_resources

dists = [str(d).replace(" ","==") for d in pkg_resources.working_set]
for i in dists:
    print(i)

How can I view array structure in JavaScript with alert()?

pass your js array to the function below and it will do the same as php print_r() function

 alert(print_r(your array));  //call it like this

function print_r(arr,level) {
var dumped_text = "";
if(!level) level = 0;

//The padding given at the beginning of the line.
var level_padding = "";
for(var j=0;j<level+1;j++) level_padding += "    ";

if(typeof(arr) == 'object') { //Array/Hashes/Objects 
    for(var item in arr) {
        var value = arr[item];

        if(typeof(value) == 'object') { //If it is an array,
            dumped_text += level_padding + "'" + item + "' ...\n";
            dumped_text += print_r(value,level+1);
        } else {
            dumped_text += level_padding + "'" + item + "' => \"" + value + "\"\n";
        }
    }
} else { //Stings/Chars/Numbers etc.
    dumped_text = "===>"+arr+"<===("+typeof(arr)+")";
}
return dumped_text;
}

Easiest way to rotate by 90 degrees an image using OpenCV?

As of OpenCV3.2, life just got a bit easier, you can now rotate an image in a single line of code:

cv::rotate(image, image, cv::ROTATE_90_CLOCKWISE);

For the direction you can choose any of the following:

ROTATE_90_CLOCKWISE
ROTATE_180
ROTATE_90_COUNTERCLOCKWISE

URL rewriting with PHP

this is an .htaccess file that forward almost all to index.php

# if a directory or a file exists, use it directly
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-l
RewriteCond %{REQUEST_URI} !-l
RewriteCond %{REQUEST_FILENAME} !\.(ico|css|png|jpg|gif|js)$ [NC]
# otherwise forward it to index.php
RewriteRule . index.php

then is up to you parse $_SERVER["REQUEST_URI"] and route to picture.php or whatever

android fragment- How to save states of views in a fragment when another fragment is pushed on top of it

I used a hybrid approach for fragments containing a list view. It seems to be performant since I don't replace the current fragment but rather add the new fragment and hide the current one. I have the following method in the activity that hosts my fragments:

public void addFragment(Fragment currentFragment, Fragment targetFragment, String tag) {
    FragmentManager fragmentManager = getSupportFragmentManager();
    FragmentTransaction transaction = fragmentManager.beginTransaction();
    transaction.setCustomAnimations(0,0,0,0);
    transaction.hide(currentFragment);
    // use a fragment tag, so that later on we can find the currently displayed fragment
    transaction.add(R.id.frame_layout, targetFragment, tag)
            .addToBackStack(tag)
            .commit();
}

I use this method in my fragment (containing the list view) whenever a list item is clicked/tapped (and thus I need to launch/display the details fragment):

FragmentManager fragmentManager = getActivity().getSupportFragmentManager();
SearchFragment currentFragment = (SearchFragment) fragmentManager.findFragmentByTag(getFragmentTags()[0]);
DetailsFragment detailsFragment = DetailsFragment.newInstance("some object containing some details");
((MainActivity) getActivity()).addFragment(currentFragment, detailsFragment, "Details");

getFragmentTags() returns an array of strings that I use as tags for different fragments when I add a new fragment (see transaction.add method in addFragment method above).

In the fragment containing the list view, I do this in its onPause() method:

@Override
public void onPause() {
    // keep the list view's state in memory ("save" it) 
    // before adding a new fragment or replacing current fragment with a new one
    ListView lv =  (ListView) getActivity().findViewById(R.id.listView);
    mListViewState = lv.onSaveInstanceState();
    super.onPause();
}

Then in onCreateView of the fragment (actually in a method that is invoked in onCreateView), I restore the state:

// Restore previous state (including selected item index and scroll position)
if(mListViewState != null) {
    Log.d(TAG, "Restoring the listview's state.");
    lv.onRestoreInstanceState(mListViewState);
}

How do I left align these Bootstrap form items?

Just add style="text-align: left" to your label.

Unresolved external symbol in object files

It looks to be missing a library or include, you can try to figure out what class of your library that have getName, getType etc ... and put that in the header file or using #include.

Also if these happen to be from an external library, make sure you reference to them on your project file. For example, if this class belongs to an abc.lib then in your Visual Studio

  1. Click on Project Properties.
  2. Go to Configuration Properties, C/C++, Generate, verify you point to the abc.lib location under Additional Include Directories. Under Linker, Input, make sure you have the abc.lib under Additional Dependencies.

What's the best three-way merge tool?

Ultracompare. It is really good, handles large files (more than 1 GB) well, is available for Windows/Mac/Linux, and it's commercial, but it is worth it.

Screen shot of UltraCompare Professional on Windows

From Arraylist to Array

assuming v is a ArrayList:

String[] x = (String[]) v.toArray(new String[0]);

How to determine if a String has non-alphanumeric characters?

One approach is to do that using the String class itself. Let's say that your string is something like that:

String s = "some text";
boolean hasNonAlpha = s.matches("^.*[^a-zA-Z0-9 ].*$");

one other is to use an external library, such as Apache commons:

String s = "some text";
boolean hasNonAlpha = !StringUtils.isAlphanumeric(s);

Read text file into string array (and write)

Cannot update first answer.
Anyway, after Go1 release, there are some breaking changes, so I updated as shown below:

package main

import (
    "os"
    "bufio"
    "bytes"
    "io"
    "fmt"
    "strings"
)

// Read a whole file into the memory and store it as array of lines
func readLines(path string) (lines []string, err error) {
    var (
        file *os.File
        part []byte
        prefix bool
    )
    if file, err = os.Open(path); err != nil {
        return
    }
    defer file.Close()

    reader := bufio.NewReader(file)
    buffer := bytes.NewBuffer(make([]byte, 0))
    for {
        if part, prefix, err = reader.ReadLine(); err != nil {
            break
        }
        buffer.Write(part)
        if !prefix {
            lines = append(lines, buffer.String())
            buffer.Reset()
        }
    }
    if err == io.EOF {
        err = nil
    }
    return
}

func writeLines(lines []string, path string) (err error) {
    var (
        file *os.File
    )

    if file, err = os.Create(path); err != nil {
        return
    }
    defer file.Close()

    //writer := bufio.NewWriter(file)
    for _,item := range lines {
        //fmt.Println(item)
        _, err := file.WriteString(strings.TrimSpace(item) + "\n"); 
        //file.Write([]byte(item)); 
        if err != nil {
            //fmt.Println("debug")
            fmt.Println(err)
            break
        }
    }
    /*content := strings.Join(lines, "\n")
    _, err = writer.WriteString(content)*/
    return
}

func main() {
    lines, err := readLines("foo.txt")
    if err != nil {
        fmt.Println("Error: %s\n", err)
        return
    }
    for _, line := range lines {
        fmt.Println(line)
    }
    //array := []string{"7.0", "8.5", "9.1"}
    err = writeLines(lines, "foo2.txt")
    fmt.Println(err)
}

How to find the logs on android studio?

Had a hard time finding the logs because the IDE was crashing on launch, if you are on Mac and use Android Studio 4.1 then the logs location may be found at /Users/{user}/Library/Logs/Google/AndroidStudio4.1/

And to be specific for me it is on macOS Big Sur

How can I create a dropdown menu from a List in Tkinter?

To create a "drop down menu" you can use OptionMenu in tkinter

Example of a basic OptionMenu:

from Tkinter import *

master = Tk()

variable = StringVar(master)
variable.set("one") # default value

w = OptionMenu(master, variable, "one", "two", "three")
w.pack()

mainloop()

More information (including the script above) can be found here.


Creating an OptionMenu of the months from a list would be as simple as:

from tkinter import *

OPTIONS = [
"Jan",
"Feb",
"Mar"
] #etc

master = Tk()

variable = StringVar(master)
variable.set(OPTIONS[0]) # default value

w = OptionMenu(master, variable, *OPTIONS)
w.pack()

mainloop()

In order to retrieve the value the user has selected you can simply use a .get() on the variable that we assigned to the widget, in the below case this is variable:

from tkinter import *

OPTIONS = [
"Jan",
"Feb",
"Mar"
] #etc

master = Tk()

variable = StringVar(master)
variable.set(OPTIONS[0]) # default value

w = OptionMenu(master, variable, *OPTIONS)
w.pack()

def ok():
    print ("value is:" + variable.get())

button = Button(master, text="OK", command=ok)
button.pack()

mainloop()

I would highly recommend reading through this site for further basic tkinter information as the above examples are modified from that site.

Spring Data: "delete by" is supported?

If you take a look at the source code of Spring Data JPA, and particularly the PartTreeJpaQuery class, you will see that is tries to instantiate PartTree. Inside that class the following regular expression

private static final Pattern PREFIX_TEMPLATE = Pattern.compile("^(find|read|get|count|query)(\\p{Lu}.*?)??By")

should indicate what is allowed and what's not.

Of course if you try to add such a method you will actually see that is does not work and you get the full stacktrace.

I should note that I was using looking at version 1.5.0.RELEASE of Spring Data JPA

How can I use xargs to copy files that have spaces and quotes in their names?

find . -print0 | grep --null 'FooBar' | xargs -0 ...

I don't know about whether grep supports --null, nor whether xargs supports -0, on Leopard, but on GNU it's all good.

How to enable local network users to access my WAMP sites?

In WAMPServer 3 you dont do this in httpd.conf

Instead edit \wamp\bin\apache\apache{version}\conf\extra\httpd-vhost.conf and do the same chnage to the Virtual Host defined for localhost

WAMPServer 3 comes with a Virtual Host pre defined for localhost

How to print a string in C++

You need to access the underlying buffer:

printf("%s\n", someString.c_str());

Or better use cout << someString << endl; (you need to #include <iostream> to use cout)

Additionally you might want to import the std namespace using using namespace std; or prefix both string and cout with std::.

SQLite select where empty?

You can do this with the following:

int counter = 0;
String sql = "SELECT projectName,Owner " + "FROM Project WHERE Owner= ?";
PreparedStatement prep = conn.prepareStatement(sql);
prep.setString(1, "");
ResultSet rs = prep.executeQuery();
while (rs.next()) {
    counter++;
}
System.out.println(counter);

This will give you the no of rows where the column value is null or blank.

How to Get the Query Executed in Laravel 5? DB::getQueryLog() Returning Empty Array

In continuing of the Apparently with Laravel 5.2, the closure in DB::listen only receives a single parameter... response above : you can put this code into the Middleware script and use it in the routes.

Additionally:

use Monolog\Logger;
use Monolog\Handler\StreamHandler;

$log = new Logger('sql');
$log->pushHandler(new StreamHandler(storage_path().'/logs/sql-' . date('Y-m-d') . '.log', Logger::INFO));

// add records to the log
$log->addInfo($query, $data);

No input file specified

The No input file specified is a message you are presented with because of the implementation of PHP on your server, which in this case indicates a CGI implementation (can be verified with phpinfo()).

Now, to properly explain this, you need to have some basic understanding on how your system works with URL's. Based on your .htaccess file, it seems that your CMS expects the URL to passed along as a PATH_INFO variable. CGI and FastCGI implementations do not have PATH_INFO available, so when trying to pass the URI along, PHP fails with that message.

We need to find an alternative.

One option is to try and fix this. Looking into the documentation for core php.ini directives you can see that you can change the workings for your implementation. Although, GoDaddy probably won't allow you to change PHP settings on a shared enviroment.

We need to find an alternative to modifying PHP settings
Looking into system/uri.php on line 40, you will see that the CMS attempts two types of URI detection - the first being PATH_INFO, which we just learned won't work - the other being the REQUEST_URI.

This should basically, be enough - but the parsing of the URI passed, will cause you more trouble, as the URI, which you could pass to REQUEST_URI variable, forces parse_url() to only return the URL path - which basically puts you back to zero.

Now, there's actually only one possibilty left - and that's changing the core of the CMS. The URI detection part is insufficient.

Add QUERY_STRING to the array on line 40 as the first element in system/uri.php and change your .htaccess to look like this:

RewriteEngine On 

RewriteCond %{REQUEST_FILENAME} !-f 
RewriteCond %{REQUEST_FILENAME} !-d 

RewriteRule ^(.*)$ index.php?/$1 [L]

This will pass the URI you request to index.php as QUERY_STRING and have the URI detection to find it.

This, on the other hand, makes it impossible to update the CMS without changing core files till this have been fixed. That sucks...

Need a better option?
Find a better CMS.

JPA and Hibernate - Criteria vs. JPQL or HQL

Most the answers here are misleading and mention that Criteria Queries are slower than HQL, which is actually not the case.

If you delve deep and perform some tests you will see Criteria Queries perform much better that regular HQL.

And also with Criteria Query you get Object Oriented control which is not there with HQL.

For more information read this answer here.

How to remove listview all items

For me worked this way:

private ListView yourListViewName;
private List<YourClassName> yourListName;

  ...

yourListName = new ArrayList<>();
yourAdapterName = new yourAdapterName(this, R.layout.your_layout_name, yourListName);

  ...

if (yourAdapterName.getCount() > 0) {
   yourAdapterName.clear();
   yourAdapterName.notifyDataSetChanged();
}

yourAdapterName.add(new YourClassName(yourParameter1, yourParameter2, ...));
yourListViewName.setAdapter(yourAdapterName);

Difference between modes a, a+, w, w+, and r+ in built-in open function?

I hit upon this trying to figure out why you would use mode 'w+' versus 'w'. In the end, I just did some testing. I don't see much purpose for mode 'w+', as in both cases, the file is truncated to begin with. However, with the 'w+', you could read after writing by seeking back. If you tried any reading with 'w', it would raise an IOError. Reading without using seek with mode 'w+' isn't going to yield anything, since the file pointer will be after where you have written.

What is the best way to give a C# auto-property an initial value?

To clarify, yes, you need to set default values in the constructor for class derived objects. You will need to ensure the constructor exists with the proper access modifier for construction where used. If the object is not instantiated, e.g. it has no constructor (e.g. static methods) then the default value can be set by the field. The reasoning here is that the object itself will be created only once and you do not instantiate it.

@Darren Kopp - good answer, clean, and correct. And to reiterate, you CAN write constructors for Abstract methods. You just need to access them from the base class when writing the constructor:

Constructor at Base Class:

public BaseClassAbstract()
{
    this.PropertyName = "Default Name";
}

Constructor at Derived / Concrete / Sub-Class:

public SubClass() : base() { }

The point here is that the instance variable drawn from the base class may bury your base field name. Setting the current instantiated object value using "this." will allow you to correctly form your object with respect to the current instance and required permission levels (access modifiers) where you are instantiating it.

Which MySQL data type to use for storing boolean values

I use TINYINT(1) in order to store boolean values in Mysql.

I don't know if there is any advantage to use this... But if i'm not wrong, mysql can store boolean (BOOL) and it store it as a tinyint(1)

http://dev.mysql.com/doc/refman/5.0/en/other-vendor-data-types.html

How to send list of file in a folder to a txt file in Linux

If only names of regular files immediately contained within a directory (assume it's ~/dirs) are needed, you can do

find ~/docs -type f -maxdepth 1 > filenames.txt

Flutter: Run method on Widget build complete

Try SchedulerBinding,

 SchedulerBinding.instance
                .addPostFrameCallback((_) => setState(() {
              isDataFetched = true;
            }));

How to Get the HTTP Post data in C#?

You can simply use Request["recipient"] to "read the HTTP values sent by a client during a Web request"

To access data from the QueryString, Form, Cookies, or ServerVariables collections, you can write Request["key"]

Source: MSDN

Update: Summarizing conversation

In order to view the values that MailGun is posting to your site you will need to read them from the web request that MailGun is making, record them somewhere and then display them on your page.

You should have one endpoint where MailGun will send the POST values to and another page that you use to view the recorded values.

It appears that right now you have one page. So when you view this page, and you read the Request values, you are reading the values from YOUR request, not MailGun.

100% width Twitter Bootstrap 3 template

Using Bootstrap 3.3.5 and .container-fluid, this is how I get full width with no gutters or horizontal scrolling on mobile. Note that .container-fluid was re-introduced in 3.1.

Full width on mobile/tablet, 1/4 screen on desktop

<div class="container-fluid"> <!-- Adds 15px left/right padding --> 
  <div class="row"> <!-- Adds -15px left/right margins -->
    <div class="col-md-4 col-md-offset-4" style="padding-left: 0, padding-right: 0"> <!-- col classes adds 15px padding, so remove the same amount -->
      <!-- Full-width for mobile -->
      <!-- 1/4 screen width for desktop -->
    </div>
  </div>
</div>

Full width on all resolutions (mobile, table, desktop)

<div class="container-fluid"> <!-- Adds 15px left/right padding -->
  <div class="row"> <!-- Adds -15px left/right margins -->
    <div>
      <!-- Full-width content -->
    </div>
  </div>
</div>

How do you get/set media volume (not ringtone volume) in Android?

Have a try with this:

setVolumeControlStream(AudioManager.STREAM_MUSIC);

How to use Git for Unity3D source control?

Unity also Provide its own Source version control. before unity5 it was unityAsset Server but now its depreciated. and launch a new SVN control system called unity collaborate.but the main problem using unity and any SVN is committing and merging scene . but Non of svn give us way to solve this kind of conflicts or merge scene . so depend upon you which SVN you are familiar with . I am using SmartSVN tool on Mac . and turtle on windows .

enter image description here

How to Query Database Name in Oracle SQL Developer?

DESCRIBE DATABASE NAME; you need to specify the name of the database and the results will include the data type of each attribute.

How do I determine if my python shell is executing in 32bit or 64bit?

platform.architecture() is problematic (and expensive).

Conveniently test for sys.maxsize > 2**32 since Py2.6 .

This is a reliable test for the actual (default) pointer size and compatible at least since Py2.3: struct.calcsize('P') == 8. Also: ctypes.sizeof(ctypes.c_void_p) == 8.

Notes: There can be builds with gcc option -mx32 or so, which are 64bit architecture applications, but use 32bit pointers as default (saving memory and speed). 'sys.maxsize = ssize_t' may not strictly represent the C pointer size (its usually 2**31 - 1 anyway). And there were/are systems which have different pointer sizes for code and data and it needs to be clarified what exactly is the purpose of discerning "32bit or 64bit mode?"

How to update values in a specific row in a Python Pandas DataFrame?

In SQL, I would have do it in one shot as

update table1 set col1 = new_value where col1 = old_value

but in Python Pandas, we could just do this:

data = [['ram', 10], ['sam', 15], ['tam', 15]] 
kids = pd.DataFrame(data, columns = ['Name', 'Age']) 
kids

which will generate the following output :

    Name    Age
0   ram     10
1   sam     15
2   tam     15

now we can run:

kids.loc[kids.Age == 15,'Age'] = 17
kids

which will show the following output

Name    Age
0   ram     10
1   sam     17
2   tam     17

which should be equivalent to the following SQL

update kids set age = 17 where age = 15

Remove blank lines with grep

I prefer using egrep, though in my test with a genuine file with blank line your approach worked fine (though without quotation marks in my test). This worked too:

egrep -v "^(\r?\n)?$" filename.txt

How to convert a 3D point into 2D perspective projection?

I think this will probably answer your question. Here's what I wrote there:

Here's a very general answer. Say the camera's at (Xc, Yc, Zc) and the point you want to project is P = (X, Y, Z). The distance from the camera to the 2D plane onto which you are projecting is F (so the equation of the plane is Z-Zc=F). The 2D coordinates of P projected onto the plane are (X', Y').

Then, very simply:

X' = ((X - Xc) * (F/Z)) + Xc

Y' = ((Y - Yc) * (F/Z)) + Yc

If your camera is the origin, then this simplifies to:

X' = X * (F/Z)

Y' = Y * (F/Z)

How do I redirect output to a variable in shell?

TL;DR

To store "abc" into $foo:

echo "abc" | read foo

But, because pipes create forks, you have to use $foo before the pipe ends, so...

echo "abc" | ( read foo; date +"I received $foo on %D"; )

Sure, all these other answers show ways to not do what the OP asked, but that really screws up the rest of us who searched for the OP's question.

The answer to the question is to use the read command.

Here's how you do it

# I would usually do this on one line, but for readability...
series | of | commands \
| \
(
  read string;
  mystic_command --opt "$string" /path/to/file
) \
| \
handle_mystified_file

Here is what it is doing and why it is important:

  1. Let's pretend that the series | of | commands is a very complicated series of piped commands.

  2. mystic_command can accept the content of a file as stdin in lieu of a file path, but not the --opt arg therefore it must come in as a variable. The command outputs the modified content and would commonly be redirected into a file or piped to another command. (E.g. sed, awk, perl, etc.)

  3. read takes stdin and places it into the variable $string

  4. Putting the read and the mystic_command into a "sub shell" via parenthesis is not necessary but makes it flow like a continuous pipe as if the 2 commands where in a separate script file.

There is always an alternative, and in this case the alternative is ugly and unreadable compared to my example above.

# my example above as a oneliner
series | of | commands | (read string; mystic_command --opt "$string" /path/to/file) | handle_mystified_file

# ugly and unreadable alternative
mystic_command --opt "$(series | of | commands)" /path/to/file | handle_mystified_file

My way is entirely chronological and logical. The alternative starts with the 4th command and shoves commands 1, 2, and 3 into command substitution.

I have a real world example of this in this script but I didn't use it as the example above because it has some other crazy/confusing/distracting bash magic going on also.

How to escape single quotes within single quoted strings

I can confirm that using '\'' for a single quote inside a single-quoted string does work in Bash, and it can be explained in the same way as the "gluing" argument from earlier in the thread. Suppose we have a quoted string: 'A '\''B'\'' C' (all quotes here are single quotes). If it is passed to echo, it prints the following: A 'B' C. In each '\'' the first quote closes the current single-quoted string, the following \' glues a single quote to the previous string (\' is a way to specify a single quote without starting a quoted string), and the last quote opens another single-quoted string.

How to change language of app when user selects language?

It's excerpt for the webpage: http://android.programmerguru.com/android-localization-at-runtime/

It's simple to change the language of your app upon user selects it from list of languages. Have a method like below which accepts the locale as String (like 'en' for English, 'hi' for hindi), configure the locale for your App and refresh your current activity to reflect the change in language. The locale you applied will not be changed until you manually change it again.

public void setLocale(String lang) { 
    Locale myLocale = new Locale(lang); 
    Resources res = getResources(); 
    DisplayMetrics dm = res.getDisplayMetrics(); 
    Configuration conf = res.getConfiguration(); 
    conf.locale = myLocale; 
    res.updateConfiguration(conf, dm); 
    Intent refresh = new Intent(this, AndroidLocalize.class); 
    finish();
    startActivity(refresh); 
} 

Make sure you imported following packages:

import java.util.Locale; 
import android.os.Bundle; 
import android.app.Activity; 
import android.content.Intent; 
import android.content.res.Configuration; 
import android.content.res.Resources; 
import android.util.DisplayMetrics; 

add in manifest to activity android:configChanges="locale|orientation"

Getting hold of the outer class object from the inner class object

Here's the example:

// Test
public void foo() {
    C c = new C();
    A s;
    s = ((A.B)c).get();
    System.out.println(s.getR());
}

// classes
class C {}

class A {
   public class B extends C{
     A get() {return A.this;}
   }
   public String getR() {
     return "This is string";
   }
}

How can I get the content of CKEditor using JQuery?

version 4.6

CKEDITOR.instances.editor.getData()

jQuery Mobile how to check if button is disabled?

Try

$("#deliveryNext").is(":disabled")

The following code works for me:

<script type="text/javascript">
    $(document).ready(function () {
        $("#testButton").button();
        $("#testButton").button('disable');
        alert($('#testButton').is(':disabled'));
    });
</script>
<p>
    <button id="testButton">Testing</button>
</p>

List of enum values in java

tl;dr

Can you make and edit a collection of objects from an enum? Yes.

If you do not care about the order, use EnumSet, an implementation of Set.

enum Animal{ DOG , CAT , BIRD , BAT ; }

Set<Animal> flyingAnimals = EnumSet.of( BIRD , BAT );

Set<Animal> featheredFlyingAnimals = flyingAnimals.clone().remove( BAT ) ;

If you care about order, use a List implementation such as ArrayList. For example, we can create a list of a person’s preference in choosing a pet, in the order of their most preferred.

List< Animal > favoritePets = new ArrayList<>() ;
favoritePets.add( CAT ) ;  // This person prefers cats over dogs…
favoritePets.add( DOG ) ;  // …but would accept either.
                           // This person would not accept a bird nor a bat.

For a non-modifiable ordered list, use List.of.

List< Animal > favoritePets = List.of( CAT , DOG ) ;  // This person prefers cats over dogs, but would accept either. This person would not accept a bird nor a bat. 

Details

The Answer (EnumSet) by Amit Deshpande and the Answer (.values) by Marko Topolnik are both correct. Here is a bit more info.

Enum.values

The .values() method is an implicitly declared method on Enum, added by the compiler. It produces a crude array rather than a Collection. Certainly usable.

Special note about documentation: Being unusual as an implicitly declared method, the .values() method is not listed among the methods on the Enum class. The method is defined in the Java Language Specification, and is mentioned in the doc for Enum.valueOf.

EnumSet – Fast & Small

The upsides to EnumSet include:

  • Extreme speed.
  • Compact use of memory.

To quote the class doc:

Enum sets are represented internally as bit vectors. This representation is extremely compact and efficient. The space and time performance of this class should be good enough to allow its use as a high-quality, typesafe alternative to traditional int-based "bit flags." Even bulk operations (such as containsAll and retainAll) should run very quickly if their argument is also an enum set.

Given this enum:

enum Animal
{
    DOG , CAT , BIRD , BAT ;
}

Make an EnumSet in one line.

Set<Animal> allAnimals = EnumSet.allOf( Animal.class );

Dump to console.

System.out.println( "allAnimals : " + allAnimals );

allAnimals : [DOG, CAT, BIRD, BAT]

Make a set from a subset of the enum objects.

Set<Animal> flyingAnimals = EnumSet.of( BIRD , BAT );

Look at the class doc to see many ways to manipulate the collection including adding or removing elements.

Set<Animal> featheredFlyingAnimals = 
    EnumSet.copyOf( flyingAnimals ).remove( BAT );

Natural Order

The doc promises the Iterator for EnumSet is in natural order, the order in which the values of the enum were originally declared.

To quote the class doc:

The iterator returned by the iterator method traverses the elements in their natural order (the order in which the enum constants are declared).

Frankly, given this promise, I'm confused why this is not a SortedSet. But, oh well, good enough. We can create a List from the Set if desired. Pass any Collection to constructor of ArrayList and that collection’s Iterator is automatically called on your behalf.

List<Animal> list = new ArrayList<>( allAnimals );

Dump to console.

System.out.println("list : " + list );

When run.

list : [DOG, CAT, BIRD, BAT]

In Java 10 and later, you can conveniently create a non-modifiable List by passing the EnumSet. The order of the new list will be in the iterator order of the EnumSet. The iterator order of an EnumSet is the order in which the element objects of the enum were defined on that enum.

List< Animal > nonModList = List.copyOf( allAnimals ) ;  // Or pass Animals.values() 

How can I access each element of a pair in a pair list?

When you say pair[0], that gives you ("a", 1). The thing in parentheses is a tuple, which, like a list, is a type of collection. So you can access the first element of that thing by specifying [0] or [1] after its name. So all you have to do to get the first element of the first element of pair is say pair[0][0]. Or if you want the second element of the third element, it's pair[2][1].

Passing a callback function to another class

Delegate is just the base class so you can't use it like that. You could do something like this though:

public void DoRequest(string request, Action<string> callback)
{
     // do stuff....
     callback("asdf");
}

CSS to make HTML page footer stay at bottom of the page with a minimum height, but not overlap the page

What I did

Html

    <div>
      <div class="register">
         /* your content*/    
      </div>
      <div class="footer" />
  <div/>

css

.register {
          min-height : calc(100vh - 10rem);
  }

.footer {
         height: 10rem;
 }

Dont need to use position fixed and absolute. Just write the html in proper way.

Check if a variable is of function type

@grandecomplex: There's a fair amount of verbosity to your solution. It would be much clearer if written like this:

function isFunction(x) {
  return Object.prototype.toString.call(x) == '[object Function]';
}

How to increase font size in a plot in R?

Notice that "cex" does change things when the plot is made with text. For example, the plot of an agglomerative hierarchical clustering:

library(cluster)
data(votes.repub)
agn1 <- agnes(votes.repub, metric = "manhattan", stand = TRUE)
plot(agn1, which.plots=2)

will produce a plot with normal sized text:

enter image description here

and plot(agn1, which.plots=2, cex=0.5) will produce this one:

enter image description here

Select multiple elements from a list

mylist[c(5,7,9)] should do it.

You want the sublists returned as sublists of the result list; you don't use [[]] (or rather, the function is [[) for that -- as Dason mentions in comments, [[ grabs the element.

In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros?

I would use something like this for fixed length, like hashes:

md5sum = String.format("%032x", new BigInteger(1, md.digest()));

The 0 in the mask does the padding...

How do I programmatically set device orientation in iOS 7?

You need to call attemptRotationToDeviceOrientation (UIViewController) to make the system call your supportedInterfaceOrientations when the condition has changed.

ASP.NET MVC passing an ID in an ActionLink to the controller

The ID will work with @ sign in front also, but we have to add one parameter after that. that is null

look like:

@Html.ActionLink("Label Name", "Name_Of_Page_To_Redirect", "Controller", new {@id="Id_Value"}, null)

Execute an action when an item on the combobox is selected

this is how you do it with ActionLIstener

import java.awt.FlowLayout;
import java.awt.event.*;

import javax.swing.*;

public class MyWind extends JFrame{

    public MyWind() {
        initialize();
    }

    private void initialize() {
        setSize(300, 300);
        setLayout(new FlowLayout(FlowLayout.LEFT));
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTextField field = new JTextField();
        field.setSize(200, 50);
        field.setText("              ");

        JComboBox comboBox = new JComboBox();
        comboBox.setEditable(true);
        comboBox.addItem("item1");
        comboBox.addItem("item2");

        //
        // Create an ActionListener for the JComboBox component.
        //
        comboBox.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent event) {
                //
                // Get the source of the component, which is our combo
                // box.
                //
                JComboBox comboBox = (JComboBox) event.getSource();

                Object selected = comboBox.getSelectedItem();
                if(selected.toString().equals("item1"))
                field.setText("30");
                else if(selected.toString().equals("item2"))
                    field.setText("40");

            }
        });
        getContentPane().add(comboBox);
        getContentPane().add(field);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new MyWind().setVisible(true);
            }
        });
    }
}

How to implement a SQL like 'LIKE' operator in java?

Check out https://github.com/hrakaroo/glob-library-java.

It's a zero dependency library in Java for doing glob (and sql like) type of comparisons. Over a large data set it is faster than translating to a regular expression.

Basic syntax

MatchingEngine m = GlobPattern.compile("dog%cat\%goat_", '%', '_', GlobPattern.HANDLE_ESCAPES);
if (m.matches(str)) { ... }

How can I add a column that doesn't allow nulls in a Postgresql database?

You have to set a default value.

ALTER TABLE mytable ADD COLUMN mycolumn character varying(50) NOT NULL DEFAULT 'foo';

... some work (set real values as you want)...

ALTER TABLE mytable ALTER COLUMN mycolumn DROP DEFAULT;

How to get a path to a resource in a Java JAR file

This is deliberate. The contents of the "file" may not be available as a file. Remember you are dealing with classes and resources that may be part of a JAR file or other kind of resource. The classloader does not have to provide a file handle to the resource, for example the jar file may not have been expanded into individual files in the file system.

Anything you can do by getting a java.io.File could be done by copying the stream out into a temporary file and doing the same, if a java.io.File is absolutely necessary.

Splitting a continuous variable into equal sized groups

If you want to split into 3 equally distributed groups, the answer is the same as Ben Bolker's answer above - use ggplot2::cut_number(). For sake of completion here are the 3 methods of converting continuous to categorical (binning).

  • cut_number(): Makes n groups with (approximately) equal numbers of observation
  • cut_interval(): Makes n groups with equal range
  • cut_width(): Makes groups of width

My go-to is cut_number() because this uses evenly spaced quantiles for binning observations. Here's an example with skewed data.

library(tidyverse)

skewed_tbl <- tibble(
    counts = c(1:100, 1:50, 1:20, rep(1:10, 3), 
               rep(1:5, 5), rep(1:2, 10), rep(1, 20))
    ) %>%
    mutate(
        counts_cut_number   = cut_number(counts, n = 4),
        counts_cut_interval = cut_interval(counts, n = 4),
        counts_cut_width    = cut_width(counts, width = 25)
        ) 

# Data
skewed_tbl
#> # A tibble: 265 x 4
#>    counts counts_cut_number counts_cut_interval counts_cut_width
#>     <dbl> <fct>             <fct>               <fct>           
#>  1      1 [1,3]             [1,25.8]            [-12.5,12.5]    
#>  2      2 [1,3]             [1,25.8]            [-12.5,12.5]    
#>  3      3 [1,3]             [1,25.8]            [-12.5,12.5]    
#>  4      4 (3,13]            [1,25.8]            [-12.5,12.5]    
#>  5      5 (3,13]            [1,25.8]            [-12.5,12.5]    
#>  6      6 (3,13]            [1,25.8]            [-12.5,12.5]    
#>  7      7 (3,13]            [1,25.8]            [-12.5,12.5]    
#>  8      8 (3,13]            [1,25.8]            [-12.5,12.5]    
#>  9      9 (3,13]            [1,25.8]            [-12.5,12.5]    
#> 10     10 (3,13]            [1,25.8]            [-12.5,12.5]    
#> # ... with 255 more rows

summary(skewed_tbl$counts)
#>    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
#>    1.00    3.00   13.00   25.75   42.00  100.00

# Histogram showing skew
skewed_tbl %>%
    ggplot(aes(counts)) +
    geom_histogram(bins = 30)

# cut_number() evenly distributes observations into bins by quantile
skewed_tbl %>%
    ggplot(aes(counts_cut_number)) +
    geom_bar()

# cut_interval() evenly splits the interval across the range
skewed_tbl %>%
    ggplot(aes(counts_cut_interval)) +
    geom_bar()

# cut_width() uses the width = 25 to create bins that are 25 in width
skewed_tbl %>%
    ggplot(aes(counts_cut_width)) +
    geom_bar()

Created on 2018-11-01 by the reprex package (v0.2.1)

What's the most efficient way to test two integer ranges for overlap?

This can easily warp a normal human brain, so I've found a visual approach to be easier to understand:

overlap madness

le Explanation

If two ranges are "too fat" to fit in a slot that is exactly the sum of the width of both, then they overlap.

For ranges [a1, a2] and [b1, b2] this would be:

/**
 * we are testing for:
 *     max point - min point < w1 + w2    
 **/
if max(a2, b2) - min(a1, b1) < (a2 - a1) + (b2 - b1) {
  // too fat -- they overlap!
}

Get width in pixels from element with style set with %?

This jQuery worked for me:

$("#banner-contenedor").css('width');

This will get you the computed width

http://api.jquery.com/css/

Pointer to class data member "::*"

Suppose you have a structure. Inside of that structure are * some sort of name * two variables of the same type but with different meaning

struct foo {
    std::string a;
    std::string b;
};

Okay, now let's say you have a bunch of foos in a container:

// key: some sort of name, value: a foo instance
std::map<std::string, foo> container;

Okay, now suppose you load the data from separate sources, but the data is presented in the same fashion (eg, you need the same parsing method).

You could do something like this:

void readDataFromText(std::istream & input, std::map<std::string, foo> & container, std::string foo::*storage) {
    std::string line, name, value;

    // while lines are successfully retrieved
    while (std::getline(input, line)) {
        std::stringstream linestr(line);
        if ( line.empty() ) {
            continue;
        }

        // retrieve name and value
        linestr >> name >> value;

        // store value into correct storage, whichever one is correct
        container[name].*storage = value;
    }
}

std::map<std::string, foo> readValues() {
    std::map<std::string, foo> foos;

    std::ifstream a("input-a");
    readDataFromText(a, foos, &foo::a);
    std::ifstream b("input-b");
    readDataFromText(b, foos, &foo::b);
    return foos;
}

At this point, calling readValues() will return a container with a unison of "input-a" and "input-b"; all keys will be present, and foos with have either a or b or both.

Is it possible to add an HTML link in the body of a MAILTO link

I have implement following it working for iOS devices but failed on android devices

<a  href="mailto:?subject=Your mate might be interested...&body=<div style='padding: 0;'><div style='padding: 0;'><p>I found this on the site I think you might find it interesting.  <a href='@(Request.Url.ToString())' >Click here </a></p></div></div>">Share This</a>

I want to load another HTML page after a specific amount of time

<script>
    setTimeout(function(){
        window.location.href = 'form2.html';
    }, 5000);
</script>

And for home page add only '/'

<script>
    setTimeout(function(){
        window.location.href = '/';
    }, 5000);
</script>

Convert generic List/Enumerable to DataTable?

Se probó el método para que acepte campos con null.

// remove "this" if not on C# 3.0 / .NET 3.5
    public static DataTable ToDataTable<T>(IList<T> data)
    {
        PropertyDescriptorCollection props =
            TypeDescriptor.GetProperties(typeof(T));
        DataTable table = new DataTable();
        Type Propiedad = null;
        for (int i = 0; i < props.Count; i++)
        {
            PropertyDescriptor prop = props[i];
            Propiedad = prop.PropertyType;
            if (Propiedad.IsGenericType && Propiedad.GetGenericTypeDefinition() == typeof(Nullable<>)) 
            {
                Propiedad = Nullable.GetUnderlyingType(Propiedad);
            }
            table.Columns.Add(prop.Name, Propiedad);
        }
        object[] values = new object[props.Count];
        foreach (T item in data)
        {
            for (int i = 0; i < values.Length; i++)
            {
                values[i] = props[i].GetValue(item);
            }
            table.Rows.Add(values);
        }
        return table;
    }

Merge PDF files with PHP

This worked for me on Windows

  1. download PDFtk free from https://www.pdflabs.com/tools/pdftk-the-pdf-toolkit/
  2. drop folder (PDFtk) into the root of c:
  3. add the following to your php code where $file1 is the location and name of the first PDF file, $file2 is the location and name of the second and $newfile is the location and name of the destination file

    $file1 = ' c:\\\www\\\folder1\\\folder2\\\file1.pdf';  
    $file2 = ' c:\\\www\\\folder1\\\folder2\\\file2.pdf';  
    $file3 = ' c:\\\www\\\folder1\\\folder2\\\file3.pdf';   
    
    $command =  'cmd /c C:\\\pdftk\\\bin\\\pdftk.exe '.$file1.$file2.$newfile;
    $result = exec($command);
    

UL has margin on the left

by default <UL/> contains default padding

therefore try adding style to padding:0px in css class or inline css

Progress Bar with HTML and CSS

Same as @RoToRa's answer, with a some slight adjustments (correct colors and dimensions):

_x000D_
_x000D_
body {_x000D_
  background-color: #636363;_x000D_
  padding: 1em;_x000D_
}_x000D_
_x000D_
#progressbar {_x000D_
  background-color: #20201F;_x000D_
  border-radius: 20px; /* (heightOfInnerDiv / 2) + padding */_x000D_
  padding: 4px;_x000D_
}_x000D_
_x000D_
#progressbar>div {_x000D_
  background-color: #F7901E;_x000D_
  width: 48%;_x000D_
  /* Adjust with JavaScript */_x000D_
  height: 16px;_x000D_
  border-radius: 10px;_x000D_
}
_x000D_
<div id="progressbar">_x000D_
  <div></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Here's the fiddle: jsFiddle

And here's what it looks like: jsFiddle-screenshot

Simple calculations for working with lat/lon and km distance?

http://www.jstott.me.uk/jcoord/ - use this library

            LatLng lld1 = new LatLng(40.718119, -73.995667);
            LatLng lld2 = new LatLng(51.499981, -0.125313);
            Double distance = lld1.distance(lld2);
            Log.d(TAG, "Distance in kilometers " + distance);

How can I make setInterval also work when a tab is inactive in Chrome?

There is a solution to use Web Workers (as mentioned before), because they run in separate process and are not slowed down

I've written a tiny script that can be used without changes to your code - it simply overrides functions setTimeout, clearTimeout, setInterval, clearInterval.

Just include it before all your code.

more info here

How do I detect whether 32-bit Java is installed on x64 Windows, only looking at the filesystem and registry?

Do you have access to the command prompt ?

Method 1 : Command Prompt

The specifics of the Java installed on the system can be determined by executing the following command java -version

Method 2 : Folder Structure

In case you do not have access to command prompt then determining the folder where Java.

32 Bit : C:\Program Files (x86)\Java\jdk1.6.0_30

64 Bit : C:\Program Files\Java\jdk1.6.0_25

However during the installation it is possible that the user might change the installation folder.

Method 3 : Registry

You can also see the version installed in registry editor.

  1. Go to registry editor

  2. Edit -> Find

  3. Search for Java. You will get the registry entries for Java.

  4. In the entry with name : DisplayName & DisplayVersion, the installed java version is displayed

How SID is different from Service name in Oracle tnsnames.ora

Please see: http://www.sap-img.com/oracle-database/finding-oracle-sid-of-a-database.htm

What is the difference between Oracle SIDs and Oracle SERVICE NAMES. One config tool looks for SERVICE NAME and then the next looks for SIDs! What's going on?!

Oracle SID is the unique name that uniquely identifies your instance/database where as Service name is the TNS alias that you give when you remotely connect to your database and this Service name is recorded in Tnsnames.ora file on your clients and it can be the same as SID and you can also give it any other name you want.

SERVICE_NAME is the new feature from oracle 8i onwards in which database can register itself with listener. If database is registered with listener in this way then you can use SERVICE_NAME parameter in tnsnames.ora otherwise - use SID in tnsnames.ora.

Also if you have OPS (RAC) you will have different SERVICE_NAME for each instance.

SERVICE_NAMES specifies one or more names for the database service to which this instance connects. You can specify multiple services names in order to distinguish among different uses of the same database. For example:

SERVICE_NAMES = sales.acme.com, widgetsales.acme.com

You can also use service names to identify a single service that is available from two different databases through the use of replication.

In an Oracle Parallel Server environment, you must set this parameter for every instance.

In short: SID = the unique name of your DB instance, ServiceName = the alias used when connecting

Flexbox Not Centering Vertically in IE

Try wrapping whatever div you have flexboxed with flex-direction: column in a container that is also flexboxed.

I just tested this in IE11 and it works. An odd fix, but until Microsoft makes their internal bug fix external...it'll have to do!

HTML:

<div class="FlexContainerWrapper">
    <div class="FlexContainer">
        <div class="FlexItem">
            <p>I should be centered.</p>
        </div>
    </div>
</div>

CSS:

html, body {
  height: 100%;
}

.FlexContainerWrapper {
  display: flex;
  flex-direction: column;
  height: 100%;
}

.FlexContainer {
  align-items: center;
  background: hsla(0,0%,0%,.1);
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 100%;
  width: 600px;
}

.FlexItem {
  background: hsla(0,0%,0%,.1);
  box-sizing: border-box;
  max-width: 100%;
}

2 examples for you to test in IE11: http://codepen.io/philipwalton/pen/JdvdJE http://codepen.io/chriswrightdesign/pen/emQNGZ/

Where is adb.exe in windows 10 located?

enter image description here

I have taken snapshot of adb.exe directory. I hope it helps you best,

nginx - nginx: [emerg] bind() to [::]:80 failed (98: Address already in use)

My issue was that I had overlapping listen directives. I have managed to figure out overlapping directives by running

grep -r listen /etc/nginx/*

Two files were listening at the same port:

/etc/nginx/conf.d/default.conf:           listen 80;  
/etc/nginx/sites-enabled/default.conf:    listen 80;

How do you access a website running on localhost from iPhone browser

If you are working on a php project you can change the base href:

<base href="<?php echo str_replace("localhost","192.x.x.x",HTTPS_SERVER);?>">

  • localhost or 127.0.0.1: depending on your settings
  • 192.x.x.x : your local ip address
  • HTTPS_SERVER: the previous base href

Doing that is essential to load images, css and js files on your phone.

Brew doctor says: "Warning: /usr/local/include isn't writable."

Same error on MacOS 10.13

/usr/local/include and /usr/local/ /usr/lib were not created. I manually created and brew link finally worked.

How to import and export components using React + ES6 + webpack?

There are two different ways of importing components in react and the recommended way is component way

  1. Library way(not recommended)
  2. Component way(recommended)

PFB detail explanation

Library way of importing

import { Button } from 'react-bootstrap';
import { FlatButton } from 'material-ui';

This is nice and handy but it does not only bundles Button and FlatButton (and their dependencies) but the whole libraries.

Component way of importing

One way to alleviate it is to try to only import or require what is needed, lets say the component way. Using the same example:

import Button from 'react-bootstrap/lib/Button';
import FlatButton from 'material-ui/lib/flat-button';

This will only bundle Button, FlatButton and their respective dependencies. But not the whole library. So I would try to get rid of all your library imports and use the component way instead.

If you are not using lot of components then it should reduce considerably the size of your bundled file.

How do I open multiple instances of Visual Studio Code?

Easiest when you don't know the CTRL+SHIFT+N shortcut is to use the menu: File, New Window

enter image description here

Increasing the Command Timeout for SQL command

Since it takes 2 mins to respond, you can increase the timeout to 3 mins by adding the below code

scGetruntotals.CommandTimeout = 180;

Note : the parameter value is in seconds.

Break promise chain and call a function based on the step in the chain where it is broken (rejected)

The best solution is to refactor to your promise chain to use ES6 await's. Then you can just return from the function to skip the rest of the behavior.

I have been hitting my head against this pattern for over a year and using await's is heaven.

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

DELETE FROM table WHERE ID NOT IN
(SELECT MAX(ID) ID FROM table)

PHP compare time

Simple way to compare time is :

$time = date('H:i:s',strtotime("11 PM"));
if($time < date('H:i:s')){
     // your code
}

Browse for a directory in C#

Note: there is no guarantee this code will work in future versions of the .Net framework. Using private .Net framework internals as done here through reflection is probably not good overall. Use the interop solution mentioned at the bottom, as the Windows API is less likely to change.

If you are looking for a Folder picker that looks more like the Windows 7 dialog, with the ability to copy and paste from a textbox at the bottom and the navigation pane on the left with favorites and common locations, then you can get access to that in a very lightweight way.

The FolderBrowserDialog UI is very minimal:

enter image description here

But you can have this instead:

enter image description here

Here's a class that opens a Vista-style folder picker using the .Net private IFileDialog interface, without directly using interop in the code (.Net takes care of that for you). It falls back to the pre-Vista dialog if not in a high enough Windows version. Should work in Windows 7, 8, 9, 10 and higher (theoretically).

using System;
using System.Reflection;
using System.Windows.Forms;

namespace MyCoolCompany.Shuriken {
    /// <summary>
    /// Present the Windows Vista-style open file dialog to select a folder. Fall back for older Windows Versions
    /// </summary>
    public class FolderSelectDialog {
        private string _initialDirectory;
        private string _title;
        private string _fileName = "";

        public string InitialDirectory {
            get { return string.IsNullOrEmpty(_initialDirectory) ? Environment.CurrentDirectory : _initialDirectory; }
            set { _initialDirectory = value; }
        }
        public string Title {
            get { return _title ?? "Select a folder"; }
            set { _title = value; }
        }
        public string FileName { get { return _fileName; } }

        public bool Show() { return Show(IntPtr.Zero); }

        /// <param name="hWndOwner">Handle of the control or window to be the parent of the file dialog</param>
        /// <returns>true if the user clicks OK</returns>
        public bool Show(IntPtr hWndOwner) {
            var result = Environment.OSVersion.Version.Major >= 6
                ? VistaDialog.Show(hWndOwner, InitialDirectory, Title)
                : ShowXpDialog(hWndOwner, InitialDirectory, Title);
            _fileName = result.FileName;
            return result.Result;
        }

        private struct ShowDialogResult {
            public bool Result { get; set; }
            public string FileName { get; set; }
        }

        private static ShowDialogResult ShowXpDialog(IntPtr ownerHandle, string initialDirectory, string title) {
            var folderBrowserDialog = new FolderBrowserDialog {
                Description = title,
                SelectedPath = initialDirectory,
                ShowNewFolderButton = false
            };
            var dialogResult = new ShowDialogResult();
            if (folderBrowserDialog.ShowDialog(new WindowWrapper(ownerHandle)) == DialogResult.OK) {
                dialogResult.Result = true;
                dialogResult.FileName = folderBrowserDialog.SelectedPath;
            }
            return dialogResult;
        }

        private static class VistaDialog {
            private const string c_foldersFilter = "Folders|\n";

            private const BindingFlags c_flags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
            private readonly static Assembly s_windowsFormsAssembly = typeof(FileDialog).Assembly;
            private readonly static Type s_iFileDialogType = s_windowsFormsAssembly.GetType("System.Windows.Forms.FileDialogNative+IFileDialog");
            private readonly static MethodInfo s_createVistaDialogMethodInfo = typeof(OpenFileDialog).GetMethod("CreateVistaDialog", c_flags);
            private readonly static MethodInfo s_onBeforeVistaDialogMethodInfo = typeof(OpenFileDialog).GetMethod("OnBeforeVistaDialog", c_flags);
            private readonly static MethodInfo s_getOptionsMethodInfo = typeof(FileDialog).GetMethod("GetOptions", c_flags);
            private readonly static MethodInfo s_setOptionsMethodInfo = s_iFileDialogType.GetMethod("SetOptions", c_flags);
            private readonly static uint s_fosPickFoldersBitFlag = (uint) s_windowsFormsAssembly
                .GetType("System.Windows.Forms.FileDialogNative+FOS")
                .GetField("FOS_PICKFOLDERS")
                .GetValue(null);
            private readonly static ConstructorInfo s_vistaDialogEventsConstructorInfo = s_windowsFormsAssembly
                .GetType("System.Windows.Forms.FileDialog+VistaDialogEvents")
                .GetConstructor(c_flags, null, new[] { typeof(FileDialog) }, null);
            private readonly static MethodInfo s_adviseMethodInfo = s_iFileDialogType.GetMethod("Advise");
            private readonly static MethodInfo s_unAdviseMethodInfo = s_iFileDialogType.GetMethod("Unadvise");
            private readonly static MethodInfo s_showMethodInfo = s_iFileDialogType.GetMethod("Show");

            public static ShowDialogResult Show(IntPtr ownerHandle, string initialDirectory, string title) {
                var openFileDialog = new OpenFileDialog {
                    AddExtension = false,
                    CheckFileExists = false,
                    DereferenceLinks = true,
                    Filter = c_foldersFilter,
                    InitialDirectory = initialDirectory,
                    Multiselect = false,
                    Title = title
                };

                var iFileDialog = s_createVistaDialogMethodInfo.Invoke(openFileDialog, new object[] { });
                s_onBeforeVistaDialogMethodInfo.Invoke(openFileDialog, new[] { iFileDialog });
                s_setOptionsMethodInfo.Invoke(iFileDialog, new object[] { (uint) s_getOptionsMethodInfo.Invoke(openFileDialog, new object[] { }) | s_fosPickFoldersBitFlag });
                var adviseParametersWithOutputConnectionToken = new[] { s_vistaDialogEventsConstructorInfo.Invoke(new object[] { openFileDialog }), 0U };
                s_adviseMethodInfo.Invoke(iFileDialog, adviseParametersWithOutputConnectionToken);

                try {
                    int retVal = (int) s_showMethodInfo.Invoke(iFileDialog, new object[] { ownerHandle });
                    return new ShowDialogResult {
                        Result = retVal == 0,
                        FileName = openFileDialog.FileName
                    };
                }
                finally {
                    s_unAdviseMethodInfo.Invoke(iFileDialog, new[] { adviseParametersWithOutputConnectionToken[1] });
                }
            }
        }

        // Wrap an IWin32Window around an IntPtr
        private class WindowWrapper : IWin32Window {
            private readonly IntPtr _handle;
            public WindowWrapper(IntPtr handle) { _handle = handle; }
            public IntPtr Handle { get { return _handle; } }
        }
    }
}

I developed this as a cleaned up version of .NET Win 7-style folder select dialog by Bill Seddon of lyquidity.com (I have no affiliation). I wrote my own because his solution requires an additional Reflection class that isn't needed for this focused purpose, uses exception-based flow control, doesn't cache the results of its reflection calls. Note that the nested static VistaDialog class is so that its static reflection variables don't try to get populated if the Show method is never called.

It is used like so in a Windows Form:

var dialog = new FolderSelectDialog {
    InitialDirectory = musicFolderTextBox.Text,
    Title = "Select a folder to import music from"
};
if (dialog.Show(Handle)) {
    musicFolderTextBox.Text = dialog.FileName;
}

You can of course play around with its options and what properties it exposes. For example, it allows multiselect in the Vista-style dialog.

Also, please note that Simon Mourier gave an answer that shows how to do the exact same job using interop against the Windows API directly, though his version would have to be supplemented to use the older style dialog if in an older version of Windows. Unfortunately, I hadn't found his post yet when I worked up my solution. Name your poison!

How to send json data in the Http request using NSURLRequest

Here is a great article using Restkit

It explains on serializing nested data into JSON and attaching the data to a HTTP POST request.

create multiple tag docker image

How not to do it:

When building an image, you could also tag it this way.

docker build -t ubuntu:14.04 .

Then you build it again with another tag:

docker build -t ubuntu:latest .

If your Dockerfile makes good use of the cache, the same image should come out, and it effectively does the same as retagging the same image. If you do docker images then you will see that they have the same ID.

There's probably a case where this goes wrong though... But like @david-braun said, you can't create tags with Dockerfiles themselves, just with the docker command.

Difference between & and && in Java?

& is bitwise AND operator comparing bits of each operand.
For example,

int a = 4;
int b = 7;
System.out.println(a & b); // prints 4
//meaning in an 32 bit system
// 00000000 00000000 00000000 00000100
// 00000000 00000000 00000000 00000111
// ===================================
// 00000000 00000000 00000000 00000100


&& is logical AND operator comparing boolean values of operands only. It takes two operands indicating a boolean value and makes a lazy evaluation on them.

How to programmatically log out from Facebook SDK 3.0 without using Facebook login/logout button?

Update for latest SDK:

Now @zeuter's answer is correct for Facebook SDK v4.7+:

LoginManager.getInstance().logOut();

Original answer:

Please do not use SessionTracker. It is an internal (package private) class, and is not meant to be consumed as part of the public API. As such, its API may change at any time without any backwards compatibility guarantees. You should be able to get rid of all instances of SessionTracker in your code, and just use the active session instead.

To answer your question, if you don't want to keep any session data, simply call closeAndClearTokenInformation when your app closes.

TSQL DATETIME ISO 8601

Gosh, NO!!! You're asking for a world of hurt if you store formatted dates in SQL Server. Always store your dates and times and one of the SQL Server "date/time" datatypes (DATETIME, DATE, TIME, DATETIME2, whatever). Let the front end code resolve the method of display and only store formatted dates when you're building a staging table to build a file from. If you absolutely must display ISO date/time formats from SQL Server, only do it at display time. I can't emphasize enough... do NOT store formatted dates/times in SQL Server.

{Edit}. The reasons for this are many but the most obvious are that, even with a nice ISO format (which is sortable), all future date calculations and searches (search for all rows in a given month, for example) will require at least an implicit conversion (which takes extra time) and if the stored formatted date isn't the format that you currently need, you'll need to first convert it to a date and then to the format you want.

The same holds true for front end code. If you store a formatted date (which is text), it requires the same gyrations to display the local date format defined either by windows or the app.

My recommendation is to always store the date/time as a DATETIME or other temporal datatype and only format the date at display time.

Loading PictureBox Image from resource file with path (Part 3)

The path should be something like: "Images\a.bmp". (Note the lack of a leading slash, and the slashes being back slashes.)

And then:

pictureBox1.Image = Image.FromFile(@"Images\a.bmp");

I just tried it to make sure, and it works. This is besides the other answer that you got - to "copy always".

How to concatenate a std::string and an int?

It seems to me that the simplest answer is to use the sprintf function:

sprintf(outString,"%s%d",name,age);

Hour from DateTime? in 24 hours format

Try this:

//String.Format("{0:HH:mm}", dt);  // where dt is a DateTime variable

public static string FormatearHoraA24(DateTime? fechaHora)
{
    if (!fechaHora.HasValue)
        return "";

    return retornar = String.Format("{0:HH:mm}", (DateTime)fechaHora);
}

Hidden features of Windows batch files

Recursively search for a string in a directory tree:

findstr /S /C:"string literal" *.*

You can also use regular expressions:

findstr /S /R "^ERROR" *.log

Recursive file search:

dir /S myfile.txt

How to send push notification to web browser?

this is simple way to do push notification for all browser https://pushjs.org

Push.create("Hello world!", {
body: "How's it hangin'?",
icon: '/icon.png',
timeout: 4000,
onClick: function () {
    window.focus();
    this.close();
 }
});

How to ignore deprecation warnings in Python

For python 3, just write below codes to ignore all warnings.

from warnings import filterwarnings
filterwarnings("ignore")

C++ floating point to integer type conversions

One thing I want to add. Sometimes, there can be precision loss. You may want to add some epsilon value first before converting. Not sure why that works... but it work.

int someint = (somedouble+epsilon);

How do you concatenate Lists in C#?

Concat returns a new sequence without modifying the original list. Try myList1.AddRange(myList2).

Collection that allows only unique items in .NET?

From the HashSet<T> page on MSDN:

The HashSet(Of T) class provides high-performance set operations. A set is a collection that contains no duplicate elements, and whose elements are in no particular order.

(emphasis mine)

Bootstrap select dropdown list placeholder

dropdown or select doesn't have a placeholder because HTML doesn't support it but it's possible to create same effect so it looks the same as other inputs placeholder

_x000D_
_x000D_
    $('select').change(function() {_x000D_
     if ($(this).children('option:first-child').is(':selected')) {_x000D_
       $(this).addClass('placeholder');_x000D_
     } else {_x000D_
      $(this).removeClass('placeholder');_x000D_
     }_x000D_
    });
_x000D_
.placeholder{color: grey;}_x000D_
select option:first-child{color: grey; display: none;}_x000D_
select option{color: #555;} // bootstrap default color
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<select class="form-control placeholder">_x000D_
   <option value="">Your Placeholder Text</option>_x000D_
   <option value="1">Text 1</option>_x000D_
   <option value="2">Text 2</option>_x000D_
   <option value="3">Text 3</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_

if you want to see first option in list remove display property from css

How to differentiate single click event and double click event?

This answer is made obsolete through time, check @kyw's solution.

I created a solution inspired by the gist posted by @AdrienSchuler. Use this solution only when you want to bind a single click AND a double click to an element. Otherwise I recommend using the native click and dblclick listeners.

These are the differences:

  • Vanillajs, No dependencies
  • Don't wait on the setTimeout to handle the click or doubleclick handler
  • When double clicking it first fires the click handler, then the doubleclick handler

Javascript:

function makeDoubleClick(doubleClickCallback, singleClickCallback) {
    var clicks = 0, timeout;
    return function() {
        clicks++;
        if (clicks == 1) {
            singleClickCallback && singleClickCallback.apply(this, arguments);
            timeout = setTimeout(function() { clicks = 0; }, 400);
        } else {
            timeout && clearTimeout(timeout);
            doubleClickCallback && doubleClickCallback.apply(this, arguments);
            clicks = 0;
        }
    };
}

Usage:

var singleClick = function(){ console.log('single click') };
var doubleClick = function(){ console.log('double click') };
element.addEventListener('click', makeDoubleClick(doubleClick, singleClick));

Below is the usage in a jsfiddle, the jQuery button is the behavior of the accepted answer.

jsfiddle

Deleting an object in C++

if it crashes on the delete line then you have almost certainly somehow corrupted the heap. We would need to see more code to diagnose the problem since the example you presented has no errors.

Perhaps you have a buffer overflow on the heap which corrupted the heap structures or even something as simple as a "double free" (or in the c++ case "double delete").

Also, as The Fuzz noted, you may have an error in your destructor as well.

And yes, it is completely normal and expected for delete to invoke the destructor, that is in fact one of its two purposes (call destructor then free memory).

Turn a string into a valid filename?

Answer modified for python 3.6

import string
import unicodedata

validFilenameChars = "-_.() %s%s" % (string.ascii_letters, string.digits)
def removeDisallowedFilenameChars(filename):
    cleanedFilename = unicodedata.normalize('NFKD', filename).encode('ASCII', 'ignore')
    return ''.join(chr(c) for c in cleanedFilename if chr(c) in validFilenameChars)

Unable to connect with remote debugger

I did @sajib s answer and used this script to redirect ports:

#!/usr/bin/env bash

# packager
adb reverse tcp:8081 tcp:8081
adb -d reverse tcp:8081 tcp:8081
adb -e reverse tcp:8081 tcp:8081

echo " React Native Packager Redirected "

Showing loading animation in center of page while making a call to Action method in ASP .NET MVC

Another solution that it is similar to those already exposed here is this one. Just before the closing body tag place this html:

<div id="resultLoading" style="display: none; width: 100%; height: 100%; position: fixed; z-index: 10000; top: 0px; left: 0px; right: 0px; bottom: 0px; margin: auto;">
    <div style="width: 340px; height: 200px; text-align: center; position: fixed; top: 0px; left: 0px; right: 0px; bottom: 0px; margin: auto; z-index: 10; color: rgb(255, 255, 255);">
        <div class="uil-default-css">
            <img src="/images/loading-animation1.gif" style="max-width: 150px; max-height: 150px; display: block; margin-left: auto; margin-right: auto;" />
        </div>
        <div class="loader-text" style="display: block; font-size: 18px; font-weight: 300;">&nbsp;</div>
    </div>
    <div style="background: rgb(0, 0, 0); opacity: 0.6; width: 100%; height: 100%; position: absolute; top: 0px;"></div>
</div>

Finally, replace .loader-text element's content on the fly on every navigation event and turn on the #resultloading div, note that it is initially hidden.

var showLoader = function (text) {
    $('#resultLoading').show();
    $('#resultLoading').find('.loader-text').html(text);
};

jQuery(document).ready(function () {
    jQuery(window).on("beforeunload ", function () {
        showLoader('Loading, please wait...');
    });
});

This can be applied to any html based project with jQuery where you don't know which pages of your administration area will take too long to finish loading.

The gif image is 176x176px but you can use any transparent gif animation, please take into account that the image size is not important as it will be maxed to 150x150px.

Also, the function showLoader can be called on an element's click to perform an action that will further redirect the page, that is why it is provided ad an individual function. i hope this can also help anyone.

Passing Objects By Reference or Value in C#

When you pass the the System.Drawing.Image type object to a method you are actually passing a copy of reference to that object.

So if inside that method you are loading a new image you are loading using new/copied reference. You are not making change in original.

YourMethod(System.Drawing.Image image)
{
    //now this image is a new reference
    //if you load a new image 
    image = new Image()..
    //you are not changing the original reference you are just changing the copy of original reference
}

force Maven to copy dependencies into target/lib

mvn install dependency:copy-dependencies 

Works for me with dependencies directory created in target folder. Like it!

How do I get a file's last modified time in Perl?

Calling the built-in function stat($fh) returns an array with the following information about the file handle passed in (from the perlfunc man page for stat):

  0 dev      device number of filesystem
  1 ino      inode number
  2 mode     file mode  (type and permissions)
  3 nlink    number of (hard) links to the file
  4 uid      numeric user ID of file's owner
  5 gid      numeric group ID of file's owner
  6 rdev     the device identifier (special files only)
  7 size     total size of file, in bytes
  8 atime    last access time since the epoch
  9 mtime    last modify time since the epoch
 10 ctime    inode change time (NOT creation time!) since the epoch
 11 blksize  preferred block size for file system I/O
 12 blocks   actual number of blocks allocated

Element number 9 in this array will give you the last modified time since the epoch (00:00 January 1, 1970 GMT). From that you can determine the local time:

my $epoch_timestamp = (stat($fh))[9];
my $timestamp       = localtime($epoch_timestamp);

Alternatively, you can use the built-in module File::stat (included as of Perl 5.004) for a more object-oriented interface.

And to avoid the magic number 9 needed in the previous example, additionally use Time::localtime, another built-in module (also included as of Perl 5.004). Together these lead to some (arguably) more legible code:

use File::stat;
use Time::localtime;
my $timestamp = ctime(stat($fh)->mtime);

how to add key value pair in the JSON object already declared

possible duplicate , best way to achieve same as stated below:

function getKey(key) {
  return `${key}`;
}

var obj = {key1: "value1", key2: "value2", [getKey('key3')]: "value3"};

https://stackoverflow.com/a/47405116/3510511

How to get the second column from command output?

This should work to get a specific column out of the command output "docker images":

REPOSITORY                          TAG                 IMAGE ID            CREATED             SIZE
ubuntu                              16.04               12543ced0f6f        10 months ago       122 MB
ubuntu                              latest              12543ced0f6f        10 months ago       122 MB
selenium/standalone-firefox-debug   2.53.0              9f3bab6e046f        12 months ago       613 MB
selenium/node-firefox-debug         2.53.0              d82f2ab74db7        12 months ago       613 MB


docker images | awk '{print $3}'

IMAGE
12543ced0f6f
12543ced0f6f
9f3bab6e046f
d82f2ab74db7

This is going to print the third column

Is there an easy way to check the .NET Framework version?

AFAIK there's no built in method in the framework that will allow you to do this. You could check this post for a suggestion on determining framework version by reading windows registry values.

How do I load an HTML page in a <div> using JavaScript?

$("button").click(function() {
    $("#target_div").load("requesting_page_url.html");
});

or

document.getElementById("target_div").innerHTML='<object type="text/html" data="requesting_page_url.html"></object>';

Show div when radio button selected

$('input[name=test]').click(function () {
    if (this.id == "watch-me") {
        $("#show-me").show('slow');
    } else {
        $("#show-me").hide('slow');
    }
});

http://jsfiddle.net/2SsAk/2/

File path issues in R using Windows ("Hex digits in character string" error)

Replacing backslash with forward slash worked for me on Windows.