Programs & Examples On #Alphanumeric

Alphanumeric refers to strings containing a combination of letters and digits.

How to remove all non-alpha numeric characters from a string in MySQL?

Based on the answer by Ryan Shillington, modified to work with strings longer than 255 characters and preserving spaces from the original string.

FYI there is lower(str) in the end.

I used this to compare strings:

DROP FUNCTION IF EXISTS spacealphanum;
DELIMITER $$
CREATE FUNCTION `spacealphanum`( str TEXT ) RETURNS TEXT CHARSET utf8
BEGIN 
  DECLARE i, len SMALLINT DEFAULT 1; 
  DECLARE ret TEXT DEFAULT ''; 
  DECLARE c CHAR(1); 
  SET len = CHAR_LENGTH( str ); 
  REPEAT 
    BEGIN 
      SET c = MID( str, i, 1 ); 
      IF c REGEXP '[[:alnum:]]' THEN 
        SET ret=CONCAT(ret,c); 
      ELSEIF  c = ' ' THEN
          SET ret=CONCAT(ret," ");
      END IF; 
      SET i = i + 1; 
    END; 
  UNTIL i > len END REPEAT; 
  SET ret = lower(ret);
  RETURN ret; 
  END $$
  DELIMITER ;

Regular expression to allow spaces between words

It was my regex: @"^(?=.{3,15}$)(?:(?:\p{L}|\p{N})[._()\[\]-]?)*$"

I just added ([\w ]+) at the end of my regex before *

@"^(?=.{3,15}$)(?:(?:\p{L}|\p{N})[._()\[\]-]?)([\w ]+)*$"

Now string is allowed to have spaces.

Determine if char is a num or letter

C99 standard on c >= '0' && c <= '9'

c >= '0' && c <= '9' (mentioned in another answer) works because C99 N1256 standard draft 5.2.1 "Character sets" says:

In both the source and execution basic character sets, the value of each character after 0 in the above list of decimal digits shall be one greater than the value of the previous.

ASCII is not guaranteed however.

How to generate a random alpha-numeric string

import java.util.*;
import javax.swing.*;

public class alphanumeric {
    public static void main(String args[]) {
        String nval, lenval;
        int n, len;

        nval = JOptionPane.showInputDialog("Enter number of codes you require: ");
        n = Integer.parseInt(nval);

        lenval = JOptionPane.showInputDialog("Enter code length you require: ");
        len = Integer.parseInt(lenval);

        find(n, len);
    }

    public static void find(int n, int length) {
        String str1 = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
        StringBuilder sb = new StringBuilder(length);
        Random r = new Random();

        System.out.println("\n\t Unique codes are \n\n");
        for(int i=0; i<n; i++) {
            for(int j=0; j<length; j++) {
                sb.append(str1.charAt(r.nextInt(str1.length())));
            }
            System.out.println("  " + sb.toString());
            sb.delete(0, length);
        }
    }
}

Regex for checking if a string is strictly alphanumeric

try this [0-9a-zA-Z]+ for only alpha and num with one char at-least..

may need modification so test on it

http://www.regexplanet.com/advanced/java/index.html

Pattern pattern = Pattern.compile("^[0-9a-zA-Z]+$");
Matcher matcher = pattern.matcher(phoneNumber);
if (matcher.matches()) {

}

How to strip all non-alphabetic characters from string in SQL Server?

Though post is a bit old, I would like to say the following. Issue I had with above solution is that it does not filter out characters like ç, ë, ï, etc. I adapted a function as follows (I only used an 80 varchar string to save memory):

create FUNCTION dbo.udf_Cleanchars (@InputString varchar(80)) 
RETURNS varchar(80) 
AS 

BEGIN 
declare @return varchar(80) , @length int , @counter int , @cur_char char(1) 
SET @return = '' 
SET @length = 0 
SET @counter = 1 
SET @length = LEN(@InputString) 
IF @length > 0 
BEGIN WHILE @counter <= @length 

BEGIN SET @cur_char = SUBSTRING(@InputString, @counter, 1) IF ((ascii(@cur_char) in (32,44,46)) or (ascii(@cur_char) between 48 and 57) or (ascii(@cur_char) between 65 and 90) or (ascii(@cur_char) between 97 and 122))
BEGIN SET @return = @return + @cur_char END 
SET @counter = @counter + 1 
END END 

RETURN @return END

Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space

Well I think you just need to add a quantifier to each pattern. Also the carriage-return thing is a little funny:

text.replace(/[^a-z0-9]+|\s+/gmi, " ");

edit The \s thing matches \r and \n too.

How do I block or restrict special characters from input fields with jquery?

[User below code to restrict special character also    

$(h.txtAmount).keydown(function (event) {
        if (event.shiftKey) {
            event.preventDefault();
        }
        if (event.keyCode == 46 || event.keyCode == 8) {
        }
        else {
            if (event.keyCode < 95) {
                if (event.keyCode < 48 || event.keyCode > 57) {
                    event.preventDefault();
                }
            }
            else {
                if (event.keyCode < 96 || event.keyCode > 105) {
                    event.preventDefault();
                }
            }
        }


    });]

HTML5 form validation pattern alphanumeric with spaces?

It's quite an old question, but in case it could be useful for anyone, starting from a combination of good responses found here, I've ended using this pattern:

pattern="([^\s][A-z0-9À-ž\s]+)"

It will require at least two characters, making sure it does not start with an empty space but allowing spaces between words, and also allowing special characters such as a, ó, ä, ö.

How do I sort strings alphabetically while accounting for value when a string is numeric?

Try this out..  



  string[] things = new string[] { "paul", "bob", "lauren", "007", "90", "-10" };

        List<int> num = new List<int>();
        List<string> str = new List<string>();
        for (int i = 0; i < things.Count(); i++)
        {

            int result;
            if (int.TryParse(things[i], out result))
            {
                num.Add(result);
            }
            else
            {
                str.Add(things[i]);
            }


        }

Now Sort the lists and merge them back...

        var strsort = from s in str
                      orderby s.Length
                      select s;

        var numsort = from n in num
                     orderby n
                     select n;

        for (int i = 0; i < things.Count(); i++)
        {

         if(i < numsort.Count())
             things[i] = numsort.ElementAt(i).ToString();
             else
             things[i] = strsort.ElementAt(i - numsort.Count());               
               }

I jsut tried to make a contribution in this interesting question...

How to remove leading zeros from alphanumeric text?

You could just do: String s = Integer.valueOf("0001007").toString();

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

Using Apache Commons Lang:

!StringUtils.isAlphanumeric(String)

Alternativly iterate over String's characters and check with:

!Character.isLetterOrDigit(char)

You've still one problem left: Your example string "abcdefà" is alphanumeric, since à is a letter. But I think you want it to be considered non-alphanumeric, right?!

So you may want to use regular expression instead:

String s = "abcdefà";
Pattern p = Pattern.compile("[^a-zA-Z0-9]");
boolean hasSpecialChar = p.matcher(s).find();

PostgreSQL: ERROR: operator does not exist: integer = character varying

I think it is telling you exactly what is wrong. You cannot compare an integer with a varchar. PostgreSQL is strict and does not do any magic typecasting for you. I'm guessing SQLServer does typecasting automagically (which is a bad thing).

If you want to compare these two different beasts, you will have to cast one to the other using the casting syntax ::.

Something along these lines:

create view view1
as 
select table1.col1,table2.col1,table3.col3
from table1 
inner join
table2 
inner join 
table3
on 
table1.col4::varchar = table2.col5
/* Here col4 of table1 is of "integer" type and col5 of table2 is of type "varchar" */
/* ERROR: operator does not exist: integer = character varying */
....;

Notice the varchar typecasting on the table1.col4.

Also note that typecasting might possibly render your index on that column unusable and has a performance penalty, which is pretty bad. An even better solution would be to see if you can permanently change one of the two column types to match the other one. Literately change your database design.

Or you could create a index on the casted values by using a custom, immutable function which casts the values on the column. But this too may prove suboptimal (but better than live casting).

How to generate graphs and charts from mysql database in php

I use highcharts. They are very interactive (and very fancy I might add). You do have to get a little creative to access data from MySQL database, but if you have a general understanding of JavaScript and PHP, you should have no problems.

CSS :not(:last-child):after selector

You can try this, I know is not the answers you are looking for but the concept is the same.

Where you are setting the styles for all the children and then removing it from the last child.

Code Snippet

li
  margin-right: 10px

  &:last-child
    margin-right: 0

Image

enter image description here

Java 8 lambda get and remove element from list

To Remove element from the list

objectA.removeIf(x -> conditions);

eg:

objectA.removeIf(x -> blockedWorkerIds.contains(x));

List<String> str1 = new ArrayList<String>();
str1.add("A");
str1.add("B");
str1.add("C");
str1.add("D");

List<String> str2 = new ArrayList<String>();
str2.add("D");
str2.add("E");

str1.removeIf(x -> str2.contains(x)); 

str1.forEach(System.out::println);

OUTPUT: A B C

Is it possible to run .APK/Android apps on iPad/iPhone devices?

There is another option not mentioned previously:

  • Pieceable Viewer has unfortunately stopped its service at December 31, 2012 but open-sourced its software. You need to compile your iOS application for the emulator and Pieceable's software will embed it in a webpage which hosts the application. This webpage can be used to run the iOS application. See Pieceable's for more details.

Disable browser's back button

Try this code. You just need to implement this code in master page and it will work for you on all the pages

<script type="text/javascript">
    window.onload = function () {
        noBack();
    }
    function noBack() {
        window.history.forward();
    }
</script>
<body  onpageshow="if (event.persisted) noBack();">
</body>

how do you insert null values into sql server

If you're using SSMS (or old school Enterprise Manager) to edit the table directly, press CTRL+0 to add a null.

Vuejs: Event on route change

Setup a watcher on the $route in your component like this:

watch:{
    $route (to, from){
        this.show = false;
    }
} 

This observes for route changes and when changed ,sets show to false

JSON to string variable dump

Here is the code I use. You should be able to adapt it to your needs.

function process_test_json() {
  var jsonDataArr = { "Errors":[],"Success":true,"Data":{"step0":{"collectionNameStr":"dei_ideas_org_Private","url_root":"http:\/\/192.168.1.128:8500\/dei-ideas_org\/","collectionPathStr":"C:\\ColdFusion8\\wwwroot\\dei-ideas_org\\wwwrootchapter0-2\\verity_collections\\","writeVerityLastFileNameStr":"C:\\ColdFusion8\\wwwroot\\dei-ideas_org\\wwwroot\\chapter0-2\\VerityLastFileName.txt","doneFlag":false,"state_dbrec":{},"errorMsgStr":"","fileroot":"C:\\ColdFusion8\\wwwroot\\dei-ideas_org\\wwwroot"}}};

  var htmlStr= "<h3 class='recurse_title'>[jsonDataArr] struct is</h3> " + recurse( jsonDataArr );
  alert( htmlStr );
  $( document.createElement('div') ).attr( "class", "main_div").html( htmlStr ).appendTo('div#out');
  $("div#outAsHtml").text( $("div#out").html() ); 
}
function recurse( data ) {
  var htmlRetStr = "<ul class='recurseObj' >"; 
  for (var key in data) {
        if (typeof(data[key])== 'object' && data[key] != null) {
            htmlRetStr += "<li class='keyObj' ><strong>" + key + ":</strong><ul class='recurseSubObj' >";
            htmlRetStr += recurse( data[key] );
            htmlRetStr += '</ul  ></li   >';
        } else {
            htmlRetStr += ("<li class='keyStr' ><strong>" + key + ': </strong>&quot;' + data[key] + '&quot;</li  >' );
        }
  };
  htmlRetStr += '</ul >';    
  return( htmlRetStr );
}

</script>
</head><body>
<button onclick="process_test_json()" >Run process_test_json()</button>
<div id="out"></div>
<div id="outAsHtml"></div>
</body>

Java - How to access an ArrayList of another class?

Two ways

1)instantiate the first class and getter for arrayList

or

2)Make arraylist as static

And finally

Java Basics By Oracle

MongoDB: How to update multiple documents with a single command?

MongoDB will find only one matching document which matches the query criteria when you are issuing an update command, whichever document matches first happens to be get updated, even if there are more documents which matches the criteria will get ignored.

so to overcome this we can specify "MULTI" option in your update statement, meaning update all those documnets which matches the query criteria. scan for all the documnets in collection finding those which matches the criteria and update :

db.test.update({"foo":"bar"},{"$set":{"test":"success!"}}, {multi:true} )

change text of button and disable button in iOS

If you want to change the title as a response to being tapped you can try this inside the IBAction method of the button in your view controller delegate. This toggles a voice chat on and off. Setting up the voice chat is not covered here!

- (IBAction)startChat:(id)sender {
UIButton *chatButton = (UIButton*)sender;
if (!voiceChat.active) {
    UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Voice Chat"
                                                                   message:@"Voice Chat will become live. Please be careful with feedback if your friend is nearby."
                                                            preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                          handler:^(UIAlertAction * action) {}];
    [alert addAction:defaultAction];
    [self presentViewController:alert animated:YES completion:nil];
    [voiceChat start];
    voiceChat.active = YES;
    [chatButton setTitle:@"Stop Chat" forState:UIControlStateNormal];
}
else {
    [voiceChat stop];
    UIAlertController* alert = [UIAlertController alertControllerWithTitle:@"Voice Chat"
                                                                   message:@"Voice Chat is closed"
                                                            preferredStyle:UIAlertControllerStyleAlert];
    UIAlertAction* defaultAction = [UIAlertAction actionWithTitle:@"OK" style:UIAlertActionStyleDefault
                                                          handler:^(UIAlertAction * action) {}];

    [alert addAction:defaultAction];
    [self presentViewController:alert animated:YES completion:nil];
    voiceChat.active = NO;
    [chatButton setTitle:@"Chat" forState:UIControlStateNormal];
}

}

voiceChat is specific to voice chat of course, but you can use your ow local boolean property to control the switch.

How to compare two dates along with time in java

Since Date implements Comparable<Date>, it is as easy as:

date1.compareTo(date2);

As the Comparable contract stipulates, it will return a negative integer/zero/positive integer if date1 is considered less than/the same as/greater than date2 respectively (ie, before/same/after in this case).

Note that Date has also .after() and .before() methods which will return booleans instead.

I get "Http failure response for (unknown url): 0 Unknown Error" instead of actual error message in Angular

For me it wasn't an angular problem. Was a field of type DateTime in the DB that has a value of (0000-00-00) and my model cannot bind that property correct so I changed to a valid value like (2019-08-12).

I'm using .net core, OData v4 and MySql (EF pomelo connector)

How can I inspect element in an Android browser?

You can inspect elements of a website in your Android device using Chrome browser.

Open your Chrome browser and go to the website you want to inspect.

Go to the address bar and type "view-source:" before the "HTTP" and reload the page.

The whole elements of the page will be shown.

WPF checkbox binding

Should be easier than that. Just use:

<Checkbox IsChecked="{Binding Path=myVar, UpdateSourceTrigger=PropertyChanged}" />

Subversion stuck due to "previous operation has not finished"?

I was facing this problem after adding a jar which is already in the SVN and I added the new Version of it with the same name.

In Eclipse I tried this

  1. Right click on folder > Team > Refresh/Cleanup.
  2. Clean, build and refresh my application.
  3. Restart the Eclipse.

Using above steps I am able to Synchronize.

Undo a Git merge that hasn't been pushed yet

If you want a command-line solution, I suggest to just go with MBO's answer.

If you're a newbie, you might like the graphical approach:

  1. Kick off gitk (from the command line, or right click in file browser if you have that)
  2. You can easily spot the merge commit there - the first node from the top with two parents
  3. Follow the link to the first/left parent (the one on your current branch before the merge, usually red for me)
  4. On the selected commit, right-click "Reset branch to here", pick the hard reset there

Is it possible to run a .NET 4.5 app on XP?

I hesitate to post this answer, it is actually technically possible but it doesn't work that well in practice. The version numbers of the CLR and the core framework assemblies were not changed in 4.5. You still target v4.0.30319 of the CLR and the framework assembly version numbers are still 4.0.0.0. The only thing that's distinctive about the assembly manifest when you look at it with a disassembler like ildasm.exe is the presence of a [TargetFramework] attribute that says that 4.5 is needed, that would have to be altered. Not actually that easy, it is emitted by the compiler.

The biggest difference is not that visible, Microsoft made a long-overdue change in the executable header of the assemblies. Which specifies what version of Windows the executable is compatible with. XP belongs to a previous generation of Windows, started with Windows 2000. Their major version number is 5. Vista was the start of the current generation, major version number 6.

.NET compilers have always specified the minimum version number to be 4.00, the version of Windows NT and Windows 9x. You can see this by running dumpbin.exe /headers on the assembly. Sample output looks like this:

OPTIONAL HEADER VALUES
             10B magic # (PE32)
            ...
            4.00 operating system version
            0.00 image version
            4.00 subsystem version              // <=== here!!
               0 Win32 version
            ...

What's new in .NET 4.5 is that the compilers change that subsystem version to 6.00. A change that was over-due in large part because Windows pays attention to that number, beyond just checking if it is small enough. It also turns on appcompat features since it assumes that the program was written to work on old versions of Windows. These features cause trouble, particularly the way Windows lies about the size of a window in Aero is troublesome. It stops lying about the fat borders of an Aero window when it can see that the program was designed to run on a Windows version that has Aero.

You can alter that version number and set it back to 4.00 by running Editbin.exe on your assemblies with the /subsystem option. This answer shows a sample postbuild event.

That's however about where the good news ends, a significant problem is that .NET 4.5 isn't very compatible with .NET 4.0. By far the biggest hang-up is that classes were moved from one assembly to another. Most notably, that happened for the [Extension] attribute. Previously in System.Core.dll, it got moved to Mscorlib.dll in .NET 4.5. That's a kaboom on XP if you declare your own extension methods, your program says to look in Mscorlib for the attribute, enabled by a [TypeForwardedTo] attribute in the .NET 4.5 version of the System.Core reference assembly. But it isn't there when you run your program on .NET 4.0

And of course there's nothing that helps you stop using classes and methods that are only available on .NET 4.5. When you do, your program will fail with a TypeLoadException or MissingMethodException when run on 4.0

Just target 4.0 and all of these problems disappear. Or break that logjam and stop supporting XP, a business decision that programmers cannot often make but can certainly encourage by pointing out the hassles that it is causing. There is of course a non-zero cost to having to support ancient operating systems, just the testing effort is substantial. A cost that isn't often recognized by management, Windows compatibility is legendary, unless it is pointed out to them. Forward that cost to the client and they tend to make the right decision a lot quicker :) But we can't help you with that.

Find which rows have different values for a given column in Teradata SQL

This works for PL/SQL:

select count(*), id,address from table group by id,address having count(*)<2

How to check if an object is defined?

If a class type is not defined, you'll get a compiler error if you try to use the class, so in that sense you should have to check.

If you have an instance, and you want to ensure it's not null, simply check for null:

if (value != null)
{
    // it's not null. 
}

mySQL :: insert into table, data from another table?

INSERT INTO Table1 SELECT * FROM Table2

Remove the last line from a file in Bash

Here is a solution using sponge (from the moreutils package):

head -n -1 foo.txt | sponge foo.txt

Summary of solutions:

  1. If you want a fast solution for large files, use the efficient tail or dd approach.

  2. If you want something easy to extend/tweak and portable, use the redirect and move approach.

  3. If you want something easy to extend/tweak, the file is not too large, portability (i.e., depending on moreutils package) is not an issue, and you are a fan of square pants, consider the sponge approach.

A nice benefit of the sponge approach, compared to "redirect and move" approaches, is that sponge preserves file permissions.

Sponge uses considerably more RAM compared to the "redirect and move" approach. This gains a bit of speed (only about 20%), but if you're interested in speed the "efficient tail" and dd approaches are the way to go.

Replace image src location using CSS

You could do this but it is hacky

.application-title {
   background:url("/path/to/image.png");
   /* set these dims according to your image size */
   width:500px;
   height:500px;
}

.application-title img {
   display:none;
}

Here is a working example:

http://jsfiddle.net/5tbxkzzc/

What is the best IDE to develop Android apps in?

An IDE which supports Android development is Processing for Android: http://wiki.processing.org/w/Android. Processing is its own language but it's easy to learn. Processing for Android requires the JDK and Android SDK to be installed but runs on its own. It runs on Linux, Mac OSX and Windows (on a side note: one can develop a desktop app in Processing and then compile it to target any of these operating systems). Its development is ongoing but it works. It's especially good for quickly sketching up an idea and running it on your Android phone (even if you plan to develop it further in another IDE).

There is an active support forum here: http://forum.processing.org/android-processing.

Checking for a null object in C++

You can use a special designated object as the null object in case of references as follows:

class SomeClass
{
    public:

        int operator==(SomeClass &object)
        {
            if(this == &object) 
            {
                    return true;
            }

            return false;
        }


    static SomeClass NullObject;
};

SomeClass SomeClass::NullObject;

void print(SomeClass &val)
{
    if(val == SomeClass::NullObject)
    {
        printf("\nNULL");
    }
    else
    {
        printf("\nNOT NULL");
    }
}

Usage of __slots__?

Each python object has a __dict__ atttribute which is a dictionary containing all other attributes. e.g. when you type self.attr python is actually doing self.__dict__['attr']. As you can imagine using a dictionary to store attribute takes some extra space & time for accessing it.

However, when you use __slots__, any object created for that class won't have a __dict__ attribute. Instead, all attribute access is done directly via pointers.

So if want a C style structure rather than a full fledged class you can use __slots__ for compacting size of the objects & reducing attribute access time. A good example is a Point class containing attributes x & y. If you are going to have a lot of points, you can try using __slots__ in order to conserve some memory.

How to use data-binding with Fragment

A complete example in data binding Fragments

FragmentMyProgramsBinding is binding class generated for res/layout/fragment_my_programs

public class MyPrograms extends Fragment {
    FragmentMyProgramsBinding fragmentMyProgramsBinding;

    public MyPrograms() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment
    FragmentMyProgramsBinding    fragmentMyProgramsBinding = DataBindingUtil.inflate(inflater, R
                .layout.fragment_my_programs, container, false);
        return fragmentMyProgramsBinding.getRoot();
    }

    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);

    }
}

How can I add numbers in a Bash script?

There are a thousand and one ways to do it. Here's one using dc (a reverse-polish desk calculator which supports unlimited precision arithmetic):

dc <<<"$num1 $num2 + p"

But if that's too bash-y for you (or portability matters) you could say

echo $num1 $num2 + p | dc

But maybe you're one of those people who thinks RPN is icky and weird; don't worry! bc is here for you:

bc <<< "$num1 + $num2"
echo $num1 + $num2 | bc

That said, there are some unrelated improvements you could be making to your script:

#!/bin/bash

num=0
metab=0

for ((i=1; i<=2; i++)); do
    for j in output-$i-* ; do # 'for' can glob directly, no need to ls
            echo "$j"

             # 'grep' can read files, no need to use 'cat'
            metab=$(grep EndBuffer "$j" | awk '{sum+=$2} END { print sum/120}')
            num=$(( $num + $metab ))
    done
    echo "$num"
done

As described in Bash FAQ 022, Bash does not natively support floating point numbers. If you need to sum floating point numbers the use of an external tool (like bc or dc) is required.

In this case the solution would be

num=$(dc <<<"$num $metab + p")

To add accumulate possibly-floating-point numbers into num.

C++ cast to derived class

Think like this:

class Animal { /* Some virtual members */ };
class Dog: public Animal {};
class Cat: public Animal {};


Dog     dog;
Cat     cat;
Animal& AnimalRef1 = dog;  // Notice no cast required. (Dogs and cats are animals).
Animal& AnimalRef2 = cat;
Animal* AnimalPtr1 = &dog;
Animal* AnimlaPtr2 = &cat;

Cat&    catRef1 = dynamic_cast<Cat&>(AnimalRef1);  // Throws an exception  AnimalRef1 is a dog
Cat*    catPtr1 = dynamic_cast<Cat*>(AnimalPtr1);  // Returns NULL         AnimalPtr1 is a dog
Cat&    catRef2 = dynamic_cast<Cat&>(AnimalRef2);  // Works
Cat*    catPtr2 = dynamic_cast<Cat*>(AnimalPtr2);  // Works

// This on the other hand makes no sense
// An animal object is not a cat. Therefore it can not be treated like a Cat.
Animal  a;
Cat&    catRef1 = dynamic_cast<Cat&>(a);    // Throws an exception  Its not a CAT
Cat*    catPtr1 = dynamic_cast<Cat*>(&a);   // Returns NULL         Its not a CAT.

Now looking back at your first statement:

Animal   animal = cat;    // This works. But it slices the cat part out and just
                          // assigns the animal part of the object.
Cat      bigCat = animal; // Makes no sense.
                          // An animal is not a cat!!!!!
Dog      bigDog = bigCat; // A cat is not a dog !!!!

You should very rarely ever need to use dynamic cast.
This is why we have virtual methods:

void makeNoise(Animal& animal)
{
     animal.DoNoiseMake();
}

Dog    dog;
Cat    cat;
Duck   duck;
Chicken chicken;

makeNoise(dog);
makeNoise(cat);
makeNoise(duck);
makeNoise(chicken);

The only reason I can think of is if you stored your object in a base class container:

std::vector<Animal*>  barnYard;
barnYard.push_back(&dog);
barnYard.push_back(&cat);
barnYard.push_back(&duck);
barnYard.push_back(&chicken);

Dog*  dog = dynamic_cast<Dog*>(barnYard[1]); // Note: NULL as this was the cat.

But if you need to cast particular objects back to Dogs then there is a fundamental problem in your design. You should be accessing properties via the virtual methods.

barnYard[1]->DoNoiseMake();

Batch command date and time in file name

I realise this is a moot question to the OP, but I just brewed this, and I'm a tad proud of myself for thinking outside the box.

Download gawk for Windows at http://gnuwin32.sourceforge.net/packages/gawk.htm .... Then it's a one liner, without all that clunky DOS batch syntax, where it takes six FOR loops to split the strings (WTF? That's really really BAD MAD AND SAD! ... IMHO of course)

If you already know C, C++, Perl, or Ruby then picking-up AWK (which inherits from the former two, and contributes significantly to the latter two) is a piece of the proverbial CAKE!!!

The DOS Batch command:

echo %DATE% %TIME% && echo %DATE% %TIME% | gawk -F"[ /:.]" "{printf(""""%s%02d%02d-%02d%02d%02d\n"""", $4, $3, $2, $5, $6, $7);}"

Prints:

Tue 04/09/2012 10:40:38.25
20120904-104038

Now that's not quite the full story... I'm just going to be lazy and hard-code the rest of my log-file-name in the printf statement, because it's simple... But if anybody knows how to set a %NOW% variable to AWK's output (yeilding the guts of a "generic" now function) then I'm all ears.


EDIT:

A quick search on Stack Overflow filled in that last piece of the puzzle, Batch equivalent of Bash backticks.

So, these three lines of DOS batch:

echo %DATE% %TIME% | awk -F"[ /:.]" "{printf(""""%s%02d%02d-%02d%02d%02d\n"""", $4, $3, $2, $5, $6, $7);}" >%temp%\now.txt
set /p now=<%temp%\now.txt
echo %now%

Produce:

20120904-114434

So now I can include a datetime in the name of the log-file produced by my SQL Server installation (2005+) script thus:

sqlcmd -S .\SQLEXPRESS -d MyDb -e -i MyTSqlCommands.sql >MyTSqlCommands.sql.%now%.log

And I'm a happy camper again (except life was still SOOOOO much easier on Unix).

How to update the value stored in Dictionary in C#?

It's possible by accessing the key as index

for example:

Dictionary<string, int> dictionary = new Dictionary<string, int>();
dictionary["test"] = 1;
dictionary["test"] += 1;
Console.WriteLine (dictionary["test"]); // will print 2

Breaking out of nested loops

In this particular case, you can merge the loops with a modern python (3.0 and probably 2.6, too) by using itertools.product.

I for myself took this as a rule of thumb, if you nest too many loops (as in, more than 2), you are usually able to extract one of the loops into a different method or merge the loops into one, as in this case.

PHP remove commas from numeric strings

Not tested, but probably something like if(preg_match("/^[0-9,]+$/", $a)) $a = str_replace(...)


Do it the other way around:

$a = "1,435";
$b = str_replace( ',', '', $a );

if( is_numeric( $b ) ) {
    $a = $b;
}

The easiest would be:

$var = intval(preg_replace('/[^\d.]/', '', $var));

or if you need float:

$var = floatval(preg_replace('/[^\d.]/', '', $var));

What is the best java image processing library/approach?

I cannot say that it is the "best" library, but I think you can try this: http://algart.net/java/AlgART/ It is an open-source Java library, supporting generalized "smart" arrays and matrices with elements of different types (from 1 bit to 64-bit floating point), including 2D-, 3D- and multidimensional image processing and other algorithms, working with arrays and matrices. Unfortunately right now it consists not enough demo and examples, but, on the other hand, it contains a lot of JavaDocs. It lay in the base of commercial software (SIMAGIS) during several years, but now it is open-source.

.NET String.Format() to add commas in thousands place for a number

If you want to show it in DataGridview , you should change its type , because default is String and since you change it to decimal it considers as Number with floating point

Dim dt As DataTable = New DataTable
dt.Columns.Add("col1", GetType(Decimal))
dt.Rows.Add(1)
dt.Rows.Add(10)
dt.Rows.Add(2)

DataGridView1.DataSource = dt

How to execute raw queries with Laravel 5.1?

I found the solution in this topic and I code this:

$cards = DB::select("SELECT
        cards.id_card,
        cards.hash_card,
        cards.`table`,
        users.name,
        0 as total,
        cards.card_status,
        cards.created_at as last_update
    FROM cards
    LEFT JOIN users
    ON users.id_user = cards.id_user
    WHERE hash_card NOT IN ( SELECT orders.hash_card FROM orders )
    UNION
    SELECT
        cards.id_card,
        orders.hash_card,
        cards.`table`,
        users.name,
        sum(orders.quantity*orders.product_price) as total, 
        cards.card_status, 
        max(orders.created_at) last_update 
    FROM menu.orders
    LEFT JOIN cards
    ON cards.hash_card = orders.hash_card
    LEFT JOIN users
    ON users.id_user = cards.id_user
    GROUP BY hash_card
    ORDER BY id_card ASC");

How to find the parent element using javascript

Using plain javascript:

element.parentNode

In jQuery:

element.parent()

How to skip the first n rows in sql query

In order to do this in SQL Server, you must order the query by a column, so you can specify the rows you want.

Example:

select * from table order by [some_column] 
offset 10 rows
FETCH NEXT 10 rows only

Save text file UTF-8 encoded with VBA

Here is another way to do this - using the API function WideCharToMultiByte:

Option Explicit

Private Declare Function WideCharToMultiByte Lib "kernel32.dll" ( _
  ByVal CodePage As Long, _
  ByVal dwFlags As Long, _
  ByVal lpWideCharStr As Long, _
  ByVal cchWideChar As Long, _
  ByVal lpMultiByteStr As Long, _
  ByVal cbMultiByte As Long, _
  ByVal lpDefaultChar As Long, _
  ByVal lpUsedDefaultChar As Long) As Long

Private Sub getUtf8(ByRef s As String, ByRef b() As Byte)
Const CP_UTF8 As Long = 65001
Dim len_s As Long
Dim ptr_s As Long
Dim size As Long
  Erase b
  len_s = Len(s)
  If len_s = 0 Then _
    Err.Raise 30030, , "Len(WideChars) = 0"
  ptr_s = StrPtr(s)
  size = WideCharToMultiByte(CP_UTF8, 0, ptr_s, len_s, 0, 0, 0, 0)
  If size = 0 Then _
    Err.Raise 30030, , "WideCharToMultiByte() = 0"
  ReDim b(0 To size - 1)
  If WideCharToMultiByte(CP_UTF8, 0, ptr_s, len_s, VarPtr(b(0)), size, 0, 0) = 0 Then _
    Err.Raise 30030, , "WideCharToMultiByte(" & Format$(size) & ") = 0"
End Sub

Public Sub writeUtf()
Dim file As Integer
Dim s As String
Dim b() As Byte
  s = "äöüßµ@€|~{}[]²³\ .." & _
    " OMEGA" & ChrW$(937) & ", SIGMA" & ChrW$(931) & _
    ", alpha" & ChrW$(945) & ", beta" & ChrW$(946) & ", pi" & ChrW$(960) & vbCrLf
  file = FreeFile
  Open "C:\Temp\TestUtf8.txt" For Binary Access Write Lock Read Write As #file
  getUtf8 s, b
  Put #file, , b
  Close #file
End Sub

Store multiple values in single key in json

{
  "number" : ["1","2","3"],
  "alphabet" : ["a", "b", "c"]
}

String contains - ignore case

You can use

org.apache.commons.lang3.StringUtils.containsIgnoreCase(CharSequence str,
                                     CharSequence searchStr);

Checks if CharSequence contains a search CharSequence irrespective of case, handling null. Case-insensitivity is defined as by String.equalsIgnoreCase(String).

A null CharSequence will return false.

This one will be better than regex as regex is always expensive in terms of performance.

For official doc, refer to : StringUtils.containsIgnoreCase

Update :

If you are among the ones who

  • don't want to use Apache commons library
  • don't want to go with the expensive regex/Pattern based solutions,
  • don't want to create additional string object by using toLowerCase,

you can implement your own custom containsIgnoreCase using java.lang.String.regionMatches

public boolean regionMatches(boolean ignoreCase,
                             int toffset,
                             String other,
                             int ooffset,
                             int len)

ignoreCase : if true, ignores case when comparing characters.

public static boolean containsIgnoreCase(String str, String searchStr)     {
    if(str == null || searchStr == null) return false;

    final int length = searchStr.length();
    if (length == 0)
        return true;

    for (int i = str.length() - length; i >= 0; i--) {
        if (str.regionMatches(true, i, searchStr, 0, length))
            return true;
    }
    return false;
}

How to parse JSON and access results

Try:

$result = curl_exec($cURL);
$result = json_decode($result,true);

Now you can access MessageID from $result['MessageID'].

As for the database, it's simply using a query like so:

INSERT INTO `tableName`(`Cancelled`,`Queued`,`SMSError`,`SMSIncommingMessage`,`Sent`,`SentDateTime`) VALUES('?','?','?','?','?');

Prepared.

How do I style a <select> dropdown with only CSS?

The blog post How to CSS form drop down style no JavaScript works for me, but it fails in Opera though:

_x000D_
_x000D_
select {_x000D_
  border: 0 none;_x000D_
  color: #FFFFFF;_x000D_
  background: transparent;_x000D_
  font-size: 20px;_x000D_
  font-weight: bold;_x000D_
  padding: 2px 10px;_x000D_
  width: 378px;_x000D_
  *width: 350px;_x000D_
  *background: #58B14C;_x000D_
}_x000D_
_x000D_
#mainselection {_x000D_
  overflow: hidden;_x000D_
  width: 350px;_x000D_
  -moz-border-radius: 9px 9px 9px 9px;_x000D_
  -webkit-border-radius: 9px 9px 9px 9px;_x000D_
  border-radius: 9px 9px 9px 9px;_x000D_
  box-shadow: 1px 1px 11px #330033;_x000D_
  background: url("arrow.gif") no-repeat scroll 319px 5px #58B14C;_x000D_
}
_x000D_
<div id="mainselection">_x000D_
  <select>_x000D_
    <option>Select an Option</option>_x000D_
    <option>Option 1</option>_x000D_
    <option>Option 2</option>_x000D_
  </select>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Is there a CSS selector for elements containing certain text?

The syntax of this question looks like Robot Framework syntax. In this case, although there is no css selector that you can use for contains, there is a SeleniumLibrary keyword that you can use instead. The Wait Until Element Contains.

Example:

Wait Until Element Contains  | ${element} | ${contains}
Wait Until Element Contains  |  td | male

java.net.ConnectException: failed to connect to /192.168.253.3 (port 2468): connect failed: ECONNREFUSED (Connection refused)

A common mistake during development of an android app running on a Virtual Device on your dev machine is to forget that the virtual device is not the same host as your dev machine. So if your server is running on your dev machine you cannot use a "http://localhost/..." url as that will look for the server endpoint on the virtual device not your dev machine.

navbar color in Twitter Bootstrap

If you are using LESS, you can use Mixins for less code. Here I will add a gradient, border, and border-radius:

.navbar-inner {
  #gradient > .vertical(#ffffff, #ECECEC);
  border: #E2E2E2;
  .border-radius(6px);
}

*If you are using the rails gem, twitter-bootstrap-rails, I do this directly in the file bootstrap_and_overrides.css.less*

Subset of rows containing NA (missing) values in a chosen column of a data frame

Try changing this:

new_DF<-dplyr::filter(DF,is.na(Var2)) 

milliseconds to days

int days = (int) (milliseconds / 86 400 000 )

Export specific rows from a PostgreSQL table as INSERT SQL script

For a data-only export use COPY.
You get a file with one table row per line as plain text (not INSERT commands), it's smaller and faster:

COPY (SELECT * FROM nyummy.cimory WHERE city = 'tokio') TO '/path/to/file.csv';

Import the same to another table of the same structure anywhere with:

COPY other_tbl FROM '/path/to/file.csv';

COPY writes and read files local to the server, unlike client programs like pg_dump or psql which read and write files local to the client. If both run on the same machine, it doesn't matter much, but it does for remote connections.

There is also the \copy command of psql that:

Performs a frontend (client) copy. This is an operation that runs an SQL COPY command, but instead of the server reading or writing the specified file, psql reads or writes the file and routes the data between the server and the local file system. This means that file accessibility and privileges are those of the local user, not the server, and no SQL superuser privileges are required.

"date(): It is not safe to rely on the system's timezone settings..."

<? date_default_timezone_set('Europe/Istanbul'); ?>

For php (or your location).

Convert Go map to json

If you had caught the error, you would have seen this:

jsonString, err := json.Marshal(datas)
fmt.Println(err)

// [] json: unsupported type: map[int]main.Foo

The thing is you cannot use integers as keys in JSON; it is forbidden. Instead, you can convert these values to strings beforehand, for instance using strconv.Itoa.

See this post for more details: https://stackoverflow.com/a/24284721/2679935

How do I open a URL from C++?

For linux environments, you can use xdg-open. It is installed by default on most distributions. The benefit over the accepted answer is that it opens the user's preferred browser.

$ xdg-open https://google.com
$ xdg-open steam://run/10

Of course you can wrap this in a system() call.

Firefox setting to enable cross domain Ajax request

I've tried using that 'UniversalBrowswerRead' thing too and it didn't work. You might be able to add an 'allow' header, but I haven't actually tried doing it yet. It's pretty new.

You can find more information here

Javax.net.ssl.SSLHandshakeException: javax.net.ssl.SSLProtocolException: SSL handshake aborted: Failure in SSL library, usually a protocol error

It was reproducible only when I use proxy on genymotion(<4.4).

Check your proxy settings in Settings-> Wireless & Networks-> WiFi->(Long Press WiredSSID)-> Modify Network

Select show advanced options: set Proxy settings to NONE.

Call to undefined function oci_connect()

Simple steps

You need to enable the below extension in your php.ini

;extension=php_oci8.dll
;extension=php_oci8_11.g.dll

by removing the ";" so that the results will below:

extension=php_oci8.dll
extension=php_oci8_11.g.dll

Download Oracle Instant Client:- Preferably 32 bit. 32 bit will also work on 64 bit. You can just google: download oracle instant client windows 32 bit. Use version 11 of the client because extension=php_oci8_11.g.dll won't work with 12. Unzip the package into a location such as C:\Oracle\instantclient_11_2.

Finally modify the System's PATH Environment Variable with end location, under system variables not user variables

Then you need to restart the System for PATH changes to fully propagate.

If you just restart XAMPP/WAMP without restarting the machine the Client's DLL files (i.e. OCL.dll) will not be loaded (nor found) by PHP's php_oci8_11g.dll extension.

Android - Set text to TextView

In layout file.

<TextView
   android:id="@+id/myTextView"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:text="Some Text"
   android:textSize="18sp"
   android:textColor="#000000"/>

In Activity

TextView myTextView = (TextView)findViewById(R.id.myTextView);
myTextView.setText("Hello World!");

Fastest way to download a GitHub project

There is a new (sometime pre April 2013) option on the site that says "Clone in Windows".

This works very nicely if you already have the Windows GitHub Client as mentioned by @Tommy in his answer on this related question (How to download source in ZIP format from GitHub?).

Can I pass a JavaScript variable to another browser window?

I have struggled to successfully pass arguments to the newly opened window.
Here is what I came up with :

function openWindow(path, callback /* , arg1 , arg2, ... */){
    var args = Array.prototype.slice.call(arguments, 2); // retrieve the arguments
    var w = window.open(path); // open the new window
    w.addEventListener('load', afterLoadWindow.bind(w, args), false); // listen to the new window's load event
    function afterLoadWindow(/* [arg1,arg2,...], loadEvent */){
        callback.apply(this, arguments[0]); // execute the callbacks, passing the initial arguments (arguments[1] contains the load event)
    }
}

Example call:

openWindow("/contact",function(firstname, lastname){
    this.alert("Hello "+firstname+" "+lastname);
}, "John", "Doe");

Live example

http://jsfiddle.net/rj6o0jzw/1/

jQuery looping .each() JSON key/value not working

With a simple JSON object, you don't need jQuery:

for (var i in json) {
   for (var j in json[i]) {
     console.log(json[i][j]);
   }
}

Internet Access in Ubuntu on VirtualBox

How did you configure networking when you created the guest? The easiest way is to set the network adapter to NAT, if you don't need to access the vm from another pc.

Jackson overcoming underscores in favor of camel-case

Annotating all model classes looks to me as an overkill and Kenny's answer didn't work for me https://stackoverflow.com/a/43271115/4437153. The result of serialization was still camel case.

I realised that there is a problem with my spring configuration, so I had to tackle that problem from another side. Hopefully someone finds it useful, but if I'm doing something against springs' rules then please let me know.

Solution for Spring MVC 5.2.5 and Jackson 2.11.2

@Configuration
@EnableWebMvc
public class WebConfig implements WebMvcConfigurer {
    @Override
    public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);           

        MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter();
        converter.setObjectMapper(objectMapper);
        converters.add(converter);
    }
}

How do you set a JavaScript onclick event to a class with css

Many 3rd party JavaScript libraries allow you to select all elements that have a CSS class of a particular name applied to them. Then you can iterate those elements and dynamically attach the handler.

There is no CSS-specific manner to do this.

In JQuery, you can do:

$(".myCssClass").click(function() { alert("hohoho"); });

What is the use of adding a null key or value to a HashMap in Java?

A null key can also be helpful when the map stores data for UI selections where the map key represents a bean field.

A corresponding null field value would for example be represented as "(please select)" in the UI selection.

Where can I find a list of Mac virtual key codes?

Below is a list of the common key codes for quick reference, taken from Events.h.

If you need to use these keycodes in an application, you should include the Carbon framework:

Objective-C:
#include <Carbon/Carbon.h>

Swift:
import Carbon.HIToolbox

You can then use the kVK_ANSI_A constants directly.


WARNING

The key constants reference physical keys on the keyboard. Their output changes if the typist is using a different keyboard layout. The letters in the constants correspond only to the U.S. QWERTY keyboard layout.

For example, the left ring-finger key on the homerow:

QWERTY keyboard layout > s > kVK_ANSI_S > "s"
Dvorak keyboard layout > o > kVK_ANSI_S > "o"

Strategies for layout-agnostic conversion of keycode to string, and vice versa, are discussed here:

How to convert ASCII character to CGKeyCode?


From Events.h:

/*
 *  Summary:
 *    Virtual keycodes
 *  
 *  Discussion:
 *    These constants are the virtual keycodes defined originally in
 *    Inside Mac Volume V, pg. V-191. They identify physical keys on a
 *    keyboard. Those constants with "ANSI" in the name are labeled
 *    according to the key position on an ANSI-standard US keyboard.
 *    For example, kVK_ANSI_A indicates the virtual keycode for the key
 *    with the letter 'A' in the US keyboard layout. Other keyboard
 *    layouts may have the 'A' key label on a different physical key;
 *    in this case, pressing 'A' will generate a different virtual
 *    keycode.
 */
enum {
  kVK_ANSI_A                    = 0x00,
  kVK_ANSI_S                    = 0x01,
  kVK_ANSI_D                    = 0x02,
  kVK_ANSI_F                    = 0x03,
  kVK_ANSI_H                    = 0x04,
  kVK_ANSI_G                    = 0x05,
  kVK_ANSI_Z                    = 0x06,
  kVK_ANSI_X                    = 0x07,
  kVK_ANSI_C                    = 0x08,
  kVK_ANSI_V                    = 0x09,
  kVK_ANSI_B                    = 0x0B,
  kVK_ANSI_Q                    = 0x0C,
  kVK_ANSI_W                    = 0x0D,
  kVK_ANSI_E                    = 0x0E,
  kVK_ANSI_R                    = 0x0F,
  kVK_ANSI_Y                    = 0x10,
  kVK_ANSI_T                    = 0x11,
  kVK_ANSI_1                    = 0x12,
  kVK_ANSI_2                    = 0x13,
  kVK_ANSI_3                    = 0x14,
  kVK_ANSI_4                    = 0x15,
  kVK_ANSI_6                    = 0x16,
  kVK_ANSI_5                    = 0x17,
  kVK_ANSI_Equal                = 0x18,
  kVK_ANSI_9                    = 0x19,
  kVK_ANSI_7                    = 0x1A,
  kVK_ANSI_Minus                = 0x1B,
  kVK_ANSI_8                    = 0x1C,
  kVK_ANSI_0                    = 0x1D,
  kVK_ANSI_RightBracket         = 0x1E,
  kVK_ANSI_O                    = 0x1F,
  kVK_ANSI_U                    = 0x20,
  kVK_ANSI_LeftBracket          = 0x21,
  kVK_ANSI_I                    = 0x22,
  kVK_ANSI_P                    = 0x23,
  kVK_ANSI_L                    = 0x25,
  kVK_ANSI_J                    = 0x26,
  kVK_ANSI_Quote                = 0x27,
  kVK_ANSI_K                    = 0x28,
  kVK_ANSI_Semicolon            = 0x29,
  kVK_ANSI_Backslash            = 0x2A,
  kVK_ANSI_Comma                = 0x2B,
  kVK_ANSI_Slash                = 0x2C,
  kVK_ANSI_N                    = 0x2D,
  kVK_ANSI_M                    = 0x2E,
  kVK_ANSI_Period               = 0x2F,
  kVK_ANSI_Grave                = 0x32,
  kVK_ANSI_KeypadDecimal        = 0x41,
  kVK_ANSI_KeypadMultiply       = 0x43,
  kVK_ANSI_KeypadPlus           = 0x45,
  kVK_ANSI_KeypadClear          = 0x47,
  kVK_ANSI_KeypadDivide         = 0x4B,
  kVK_ANSI_KeypadEnter          = 0x4C,
  kVK_ANSI_KeypadMinus          = 0x4E,
  kVK_ANSI_KeypadEquals         = 0x51,
  kVK_ANSI_Keypad0              = 0x52,
  kVK_ANSI_Keypad1              = 0x53,
  kVK_ANSI_Keypad2              = 0x54,
  kVK_ANSI_Keypad3              = 0x55,
  kVK_ANSI_Keypad4              = 0x56,
  kVK_ANSI_Keypad5              = 0x57,
  kVK_ANSI_Keypad6              = 0x58,
  kVK_ANSI_Keypad7              = 0x59,
  kVK_ANSI_Keypad8              = 0x5B,
  kVK_ANSI_Keypad9              = 0x5C
};

/* keycodes for keys that are independent of keyboard layout*/
enum {
  kVK_Return                    = 0x24,
  kVK_Tab                       = 0x30,
  kVK_Space                     = 0x31,
  kVK_Delete                    = 0x33,
  kVK_Escape                    = 0x35,
  kVK_Command                   = 0x37,
  kVK_Shift                     = 0x38,
  kVK_CapsLock                  = 0x39,
  kVK_Option                    = 0x3A,
  kVK_Control                   = 0x3B,
  kVK_RightShift                = 0x3C,
  kVK_RightOption               = 0x3D,
  kVK_RightControl              = 0x3E,
  kVK_Function                  = 0x3F,
  kVK_F17                       = 0x40,
  kVK_VolumeUp                  = 0x48,
  kVK_VolumeDown                = 0x49,
  kVK_Mute                      = 0x4A,
  kVK_F18                       = 0x4F,
  kVK_F19                       = 0x50,
  kVK_F20                       = 0x5A,
  kVK_F5                        = 0x60,
  kVK_F6                        = 0x61,
  kVK_F7                        = 0x62,
  kVK_F3                        = 0x63,
  kVK_F8                        = 0x64,
  kVK_F9                        = 0x65,
  kVK_F11                       = 0x67,
  kVK_F13                       = 0x69,
  kVK_F16                       = 0x6A,
  kVK_F14                       = 0x6B,
  kVK_F10                       = 0x6D,
  kVK_F12                       = 0x6F,
  kVK_F15                       = 0x71,
  kVK_Help                      = 0x72,
  kVK_Home                      = 0x73,
  kVK_PageUp                    = 0x74,
  kVK_ForwardDelete             = 0x75,
  kVK_F4                        = 0x76,
  kVK_End                       = 0x77,
  kVK_F2                        = 0x78,
  kVK_PageDown                  = 0x79,
  kVK_F1                        = 0x7A,
  kVK_LeftArrow                 = 0x7B,
  kVK_RightArrow                = 0x7C,
  kVK_DownArrow                 = 0x7D,
  kVK_UpArrow                   = 0x7E
};

Macintosh Toolbox Essentials illustrates the physical locations of these virtual key codes for the Apple Extended Keyboard II in Figure 2-10:

Virtual key codes for the Apple Extended Keyboard II

Create a simple 10 second countdown

A solution using Promises, includes both progress bar & text countdown.

_x000D_
_x000D_
ProgressCountdown(10, 'pageBeginCountdown', 'pageBeginCountdownText').then(value => alert(`Page has started: ${value}.`));_x000D_
_x000D_
function ProgressCountdown(timeleft, bar, text) {_x000D_
  return new Promise((resolve, reject) => {_x000D_
    var countdownTimer = setInterval(() => {_x000D_
      timeleft--;_x000D_
_x000D_
      document.getElementById(bar).value = timeleft;_x000D_
      document.getElementById(text).textContent = timeleft;_x000D_
_x000D_
      if (timeleft <= 0) {_x000D_
        clearInterval(countdownTimer);_x000D_
        resolve(true);_x000D_
      }_x000D_
    }, 1000);_x000D_
  });_x000D_
}
_x000D_
<div class="row begin-countdown">_x000D_
  <div class="col-md-12 text-center">_x000D_
    <progress value="10" max="10" id="pageBeginCountdown"></progress>_x000D_
    <p> Begining in <span id="pageBeginCountdownText">10 </span> seconds</p>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Execute external program

import java.io.*;

public class Code {
  public static void main(String[] args) throws Exception {
    ProcessBuilder builder = new ProcessBuilder("ls", "-ltr");
    Process process = builder.start();

    StringBuilder out = new StringBuilder();
    try (BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()))) {
        String line = null;
      while ((line = reader.readLine()) != null) {
        out.append(line);
        out.append("\n");
      }
      System.out.println(out);
    }
  }
}

Try online

OnChange event using React JS for drop down

Thank you Felix Kling, but his answer need a little change:

var MySelect = React.createClass({
 getInitialState: function() {
     return {
         value: 'select'
     }
 },
 change: function(event){
     this.setState({value: event.target.value});
 },
 render: function(){
    return(
       <div>
           <select id="lang" onChange={this.change.bind(this)} value={this.state.value}>
              <option value="select">Select</option>
              <option value="Java">Java</option>
              <option value="C++">C++</option>
           </select>
           <p></p>
           <p>{this.state.value}</p>
       </div>
    );
 }
});
React.render(<MySelect />, document.body); 

Android Studio Rendering Problems : The following classes could not be found

I have faced this issue when I introduced additional supporting libraries in my project IntelliJ IDEA

So for me "File" -> "Invalidate Caches...", and select "Invalidate and Restart" option to fix this.

ImportError: Cannot import name X

If you are importing file1.py from file2.py and used this:

if __name__ == '__main__':
    # etc

Variables below that in file1.py cannot be imported to file2.py because __name__ does not equal __main__!

If you want to import something from file1.py to file2.py, you need to use this in file1.py:

if __name__ == 'file1':
    # etc

In case of doubt, make an assert statement to determine if __name__=='__main__'

SSIS how to set connection string dynamically from a config file

These answers are right, but old and works for Depoloyement Package Model. What I Actually needed is to change the server name, database name of a connection manager and i found this very helpful:

https://www.youtube.com/watch?v=_yLAwTHH_GA

Better for people using SQL Server 2012-2014-2016 ... with Deployment Project Model

How to detect running app using ADB command

I just noticed that top is available in adb, so you can do things like

  adb shell
  top -m 5

to monitor the top five CPU hogging processes.

Or

  adb shell top -m 5 -s cpu -n 20 |tee top.log

to record this for one minute and collect the output to a file on your computer.

Accuracy Score ValueError: Can't Handle mix of binary and continuous target

accuracy_score is a classification metric, you cannot use it for a regression problem.

You can see the available regression metrics here

How do I output text without a newline in PowerShell?

desired o/p: Enabling feature XYZ......Done

you can use below command

$a = "Enabling feature XYZ"

Write-output "$a......Done"

you have to add variable and statement inside quotes. hope this is helpful :)

Thanks Techiegal

Compare object instances for equality by their attributes

Implement the __eq__ method in your class; something like this:

def __eq__(self, other):
    return self.path == other.path and self.title == other.title

Edit: if you want your objects to compare equal if and only if they have equal instance dictionaries:

def __eq__(self, other):
    return self.__dict__ == other.__dict__

How to set up Spark on Windows?

I found the easiest solution on Windows is to build from source.

You can pretty much follow this guide: http://spark.apache.org/docs/latest/building-spark.html

Download and install Maven, and set MAVEN_OPTS to the value specified in the guide.

But if you're just playing around with Spark, and don't actually need it to run on Windows for any other reason that your own machine is running Windows, I'd strongly suggest you install Spark on a linux virtual machine. The simplest way to get started probably is to download the ready-made images made by Cloudera or Hortonworks, and either use the bundled version of Spark, or install your own from source or the compiled binaries you can get from the spark website.

How can I install a package with go get?

First, we need GOPATH

The $GOPATH is a folder (or set of folders) specified by its environment variable. We must notice that this is not the $GOROOT directory where Go is installed.

export GOPATH=$HOME/gocode
export PATH=$PATH:$GOPATH/bin

We used ~/gocode path in our computer to store the source of our application and its dependencies. The GOPATH directory will also store the binaries of their packages.

Then check Go env

You system must have $GOPATH and $GOROOT, below is my Env:

GOARCH="amd64"
GOBIN=""
GOCHAR="6"
GOEXE=""
GOHOSTARCH="amd64"
GOHOSTOS="linux"
GOOS="linux"
GOPATH="/home/elpsstu/gocode"
GORACE=""
GOROOT="/home/pravin/go"
GOTOOLDIR="/home/pravin/go/pkg/tool/linux_amd64"
CC="gcc"
GOGCCFLAGS="-fPIC -m64 -pthread -fmessage-length=0"
CXX="g++"
CGO_ENABLED="1"

Now, you run download go package:

go get [-d] [-f] [-fix] [-t] [-u] [build flags] [packages]

Get downloads and installs the packages named by the import paths, along with their dependencies. For more details you can look here.

Catch checked change event of a checkbox

This code does what your need:

<input type="checkbox" id="check" >check it</input>

$("#check").change( function(){
   if( $(this).is(':checked') ) {
        alert("checked");
    }else{
        alert("unchecked");
   }
});

Also, you can check it on jsfiddle

Is there a command line utility for rendering GitHub flavored Markdown?

Improving upon @barry-stae's solution. Stick this snippet in ~/.bashrc

function mdviewer(){
  pandoc $* | lynx -stdin
}

Then we can quickly view the file from the command-line. Also works nicely over SSH/Telnet sessions.

mdviewer README.md

Error: Cannot pull with rebase: You have unstaged changes

If you want to automatically stash your changes and unstash them for every rebase, you can do this:

git config --global rebase.autoStash true

Combine two arrays

You should take to consideration that $array1 + $array2 != $array2 + $array1

$array1 = array(
'11' => 'x1',
'22' => 'x1' 
);  

$array2 = array(
'22' => 'x2',
'33' => 'x2' 
);

with $array1 + $array2

$array1 + $array2 = array(
'11' => 'x1',
'22' => 'x1',
'33' => 'x2'
);

and with $array2 + $array1

$array2 + $array1 = array(  
'11' => 'x1',  
'22' => 'x2',  
'33' => 'x2'  
);

Find CRLF in Notepad++

I was totally unable to do this in NP v6.9. I found it easy enough on Msoft Word (2K).

Open the doc, go to edit->replace.

Then in the bottom of the search box, click "more" then find the "Special" button and they have several things for you. For Dos style, I used the "paragraph" one. This is a cr lf pair in windows land.

TensorFlow, "'module' object has no attribute 'placeholder'"

If you are using TensorFlow 2.0, then some code developed for tf 1.x may not code work. Either you can follow the link : https://www.tensorflow.org/guide/migrate

or you can install a previous version of tf by pip3 install tensorflow==version

How do I convert two lists into a dictionary?

You may also try with one list which is a combination of two lists ;)

a = [1,2,3,4]
n = [5,6,7,8]

x = []
for i in a,n:
    x.append(i)

print(dict(zip(x[0], x[1])))

Get installed applications in a system

While the accepted solution works, it is not complete. By far.

If you want to get all the keys, you need to take into consideration 2 more things:

x86 & x64 applications do not have access to the same registry. Basically x86 cannot normally access x64 registry. And some applications only register to the x64 registry.

and

some applications actually install into the CurrentUser registry instead of the LocalMachine

With that in mind, I managed to get ALL installed applications using the following code, WITHOUT using WMI

Here is the code:

List<string> installs = new List<string>();
List<string> keys = new List<string>() {
  @"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall",
  @"SOFTWARE\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall"
};

// The RegistryView.Registry64 forces the application to open the registry as x64 even if the application is compiled as x86 
FindInstalls(RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64), keys, installs);
FindInstalls(RegistryKey.OpenBaseKey(RegistryHive.CurrentUser, RegistryView.Registry64), keys, installs);

installs = installs.Where(s => !string.IsNullOrWhiteSpace(s)).Distinct().ToList();
installs.Sort(); // The list of ALL installed applications



private void FindInstalls(RegistryKey regKey, List<string> keys, List<string> installed)
{
  foreach (string key in keys)
  {
    using (RegistryKey rk = regKey.OpenSubKey(key))
    {
      if (rk == null)
      {
        continue;
      }
      foreach (string skName in rk.GetSubKeyNames())
      {
        using (RegistryKey sk = rk.OpenSubKey(skName))
        {
          try
          {
            installed.Add(Convert.ToString(sk.GetValue("DisplayName")));
          }
          catch (Exception ex)
          { }
        }
      }
    }
  }
}

Getting the Username from the HKEY_USERS values

The proper way to do this requires leveraging the SAM registry hive (on Windows 10, this requires NT AUTHORITY\SYSTEM privileges). The information you require is in the the key: HKEY_LOCAL_MACHINE\SAM\SAM\Domains\Account\Users\Names.

Each subkey is the username, and the default value in each subkey is a binary integer. This value (converted to decimal) actually corresponds to the last chunk of the of the SID.

Take "Administrator" for example, by default it is associated with the integer 0x1f4 (or 500).

So, in theory you could take the build a list of SIDS based on the subkey names of the HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\ProfileList key and/or HKEY_USERS key, parse out the the value after the last hyphen (-), and compare that to the info from the SAM hive.

If you don't have NT AUTHORITY\SYSTEM privileges, the next best way to approach this may be to follow the other method described in the answers here.

reference: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-dtyp/81d92bba-d22b-4a8c-908a-554ab29148ab

How to unpack pkl file?

The pickle (and gzip if the file is compressed) module need to be used

NOTE: These are already in the standard Python library. No need to install anything new

I just discovered why all ASP.Net websites are slow, and I am trying to work out what to do about it

I prepared a library based on links posted in this thread. It uses the examples from MSDN and CodeProject. Thanks to James.

I also made modifications advised by Joel Mueller.

Code is here:

https://github.com/dermeister0/LockFreeSessionState

HashTable module:

Install-Package Heavysoft.LockFreeSessionState.HashTable

ScaleOut StateServer module:

Install-Package Heavysoft.LockFreeSessionState.Soss

Custom module:

Install-Package Heavysoft.LockFreeSessionState.Common

If you want to implement support of Memcached or Redis, install this package. Then inherit the LockFreeSessionStateModule class and implement abstract methods.

The code is not tested on production yet. Also need to improve error handling. Exceptions are not caught in current implementation.

Some lock-free session providers using Redis:

Convert Object to JSON string

You can use the excellent jquery-Json plugin:

http://code.google.com/p/jquery-json/

Makes it easy to convert to and from Json objects.

How to vertically center a <span> inside a div?

To the parent div add a height say 50px. In the child span, add the line-height: 50px; Now the text in the span will be vertically center. This worked for me.

How do I remove the height style from a DIV using jQuery?

To reset the height of the div, just try

$("#someDiv").height('auto');

Finding the number of days between two dates

If you want to echo all days between the start and end date, I came up with this :

$startdatum = $_POST['start']; // starting date
$einddatum = $_POST['eind']; // end date

$now = strtotime($startdatum);
$your_date = strtotime($einddatum);
$datediff = $your_date - $now;
$number = floor($datediff/(60*60*24));

for($i=0;$i <= $number; $i++)
{
    echo date('d-m-Y' ,strtotime("+".$i." day"))."<br>";
}

pandas dataframe convert column type to string or categorical

You need astype:

df['zipcode'] = df.zipcode.astype(str)
#df.zipcode = df.zipcode.astype(str)

For converting to categorical:

df['zipcode'] = df.zipcode.astype('category')
#df.zipcode = df.zipcode.astype('category')

Another solution is Categorical:

df['zipcode'] = pd.Categorical(df.zipcode)

Sample with data:

import pandas as pd

df = pd.DataFrame({'zipcode': {17384: 98125, 2680: 98107, 722: 98005, 18754: 98109, 14554: 98155}, 'bathrooms': {17384: 1.5, 2680: 0.75, 722: 3.25, 18754: 1.0, 14554: 2.5}, 'sqft_lot': {17384: 1650, 2680: 3700, 722: 51836, 18754: 2640, 14554: 9603}, 'bedrooms': {17384: 2, 2680: 2, 722: 4, 18754: 2, 14554: 4}, 'sqft_living': {17384: 1430, 2680: 1440, 722: 4670, 18754: 1130, 14554: 3180}, 'floors': {17384: 3.0, 2680: 1.0, 722: 2.0, 18754: 1.0, 14554: 2.0}})
print (df)
       bathrooms  bedrooms  floors  sqft_living  sqft_lot  zipcode
722         3.25         4     2.0         4670     51836    98005
2680        0.75         2     1.0         1440      3700    98107
14554       2.50         4     2.0         3180      9603    98155
17384       1.50         2     3.0         1430      1650    98125
18754       1.00         2     1.0         1130      2640    98109

print (df.dtypes)
bathrooms      float64
bedrooms         int64
floors         float64
sqft_living      int64
sqft_lot         int64
zipcode          int64
dtype: object

df['zipcode'] = df.zipcode.astype('category')

print (df)
       bathrooms  bedrooms  floors  sqft_living  sqft_lot zipcode
722         3.25         4     2.0         4670     51836   98005
2680        0.75         2     1.0         1440      3700   98107
14554       2.50         4     2.0         3180      9603   98155
17384       1.50         2     3.0         1430      1650   98125
18754       1.00         2     1.0         1130      2640   98109

print (df.dtypes)
bathrooms       float64
bedrooms          int64
floors          float64
sqft_living       int64
sqft_lot          int64
zipcode        category
dtype: object

How to convert an image to base64 encoding?

Here is the code for upload to encode and save it to the MySQL

if (!isset($_GET["getfile"])) {
    if ($_FILES["file"]["error"] > 0) {
        echo "Error: " . $_FILES["file"]["error"] . "<br>";
    } else {
        move_uploaded_file($_FILES["file"]["tmp_name"], $_FILES["file"]["name"]);

        $bin_string = file_get_contents($_FILES["file"]["name"]);
        $hex_string = base64_encode($bin_string);
        $mysqli = mysqli_init();

        if (!$mysqli->real_connect('localhost', 'root', '', 'arihant')) {
            die('Connect Error (' . mysqli_connect_errno() . ') ' . mysqli_connect_error());
        }

        $mysqli->query("INSERT INTO upload(image) VALUES ('" . $hex_string . "')");
    }
}

For showing the image use this

echo "<img src='data:image/jpeg;base64, $image' width=300>";

Setting the focus to a text field

For me the easiest way to get it to work, is to put the component.requestFocus(); line, after the setVisible(true); line, at the bottom of your frame or panel constructor.

This probably has something to do with asking for the focus, after all components have been created, because creating a new component, after asking for the focus request, will make your component loose te focus, and make the focus go to your newly created component. At least, that's what I assume.

Accessing constructor of an anonymous class

Yes , It is right that you can not define construct in an Anonymous class but it doesn't mean that anonymous class don't have constructor. Confuse... Actually you can not define construct in an Anonymous class but compiler generates an constructor for it with the same signature as its parent constructor called. If the parent has more than one constructor, the anonymous will have one and only one constructor

Converting a pointer into an integer

Use uintptr_t as your integer type.

Defining a percentage width for a LinearLayout?

Google introduced new API called PercentRelativeLayout

Add compile dependency like

compile 'com.android.support:percent:22.2.0'

in that PercentRelativeLayout is what we can do percentagewise layout

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

I just did the following (in V 3.5) and it worked like a charm:

<p:column headerText="name" width="20px"/>

How to make a text box have rounded corners?

This can be done with CSS3:

<input type="text" />

input
{
  -moz-border-radius: 15px;
 border-radius: 15px;
    border:solid 1px black;
    padding:5px;
}

http://jsfiddle.net/UbSkn/1/


However, an alternative would be to put the input inside a div with a rounded background, and no border on the input

How to generate a create table script for an existing table in phpmyadmin?

Use the following query in sql tab:

SHOW CREATE TABLE tablename

To view full query There is this Hyperlink named +Options left above, There select Full Texts

Your project path contains non-ASCII characters android studio

I solved this issue by adding this line

android.overridePathCheck=true

to

gradle.properties

As this message said

This warning can be disabled by using 
the command line flag -Dcom.android.build.gradle.overridePathCheck=true,
 or adding the line 
'com.android.build.gradle.overridePathCheck=true'
 to gradle.properties file in the project directory.

How can I style a PHP echo text?

You cannot style a variable such as $ip['countryName']

You can only style elements like p,div, etc, or classes and ids.

If you want to style $ip['countryName'] there are several ways.

You can echo it within an element:

echo '<p id="style">'.$ip['countryName'].'</p>';
echo '<span id="style">'.$ip['countryName'].'</span>';
echo '<div id="style">'.$ip['countryName'].'</div>';

If you want to style both the variables the same style, then set a class like:

echo '<p class="style">'.$ip['cityName'].'</p>';
echo '<p class="style">'.$ip['countryName'].'</p>';

You could also embed the variables within your actual html rather than echoing them out within the code.

$city = $ip['cityName'];  
$country = $ip['countryName'];
?>
<div class="style"><?php echo $city ?></div>
<div class="style"><?php echo $country?></div>

Open a URL in a new tab (and not a new window)

Somehow a website can do it. (I don't have the time to extract it from this mess, but this is the code)

if (!Array.prototype.indexOf)
    Array.prototype.indexOf = function(searchElement, fromIndex) {
        if (this === undefined || this === null)
            throw new TypeError('"this" is null or not defined');
        var length = this.length >>> 0;
        fromIndex = +fromIndex || 0;
        if (Math.abs(fromIndex) === Infinity)
            fromIndex = 0;
        if (fromIndex < 0) {
            fromIndex += length;
            if (fromIndex < 0)
                fromIndex = 0
        }
        for (; fromIndex < length; fromIndex++)
            if (this[fromIndex] === searchElement)
                return fromIndex;
        return -1
    };
(function Popunder(options) {
    var _parent, popunder, posX, posY, cookieName, cookie, browser, numberOfTimes, expires = -1,
        wrapping, url = "",
        size, frequency, mobilePopupDisabled = options.mobilePopupDisabled;
    if (this instanceof Popunder === false)
        return new Popunder(options);
    try {
        _parent = top != self && typeof top.document.location.toString() === "string" ? top : self
    } catch (e) {
        _parent = self
    }
    cookieName = "adk2_popunder";
    popunder = null;
    browser = function() {
        var n = navigator.userAgent.toLowerCase(),
            b = {
                webkit: /webkit/.test(n),
                mozilla: /mozilla/.test(n) && !/(compatible|webkit)/.test(n),
                chrome: /chrome/.test(n),
                msie: /msie/.test(n) && !/opera/.test(n),
                firefox: /firefox/.test(n),
                safari: /safari/.test(n) && !/chrome/.test(n),
                opera: /opera/.test(n)
            };
        b.version = b.safari ? (n.match(/.+(?:ri)[\/: ]([\d.]+)/) || [])[1] : (n.match(/.+(?:ox|me|ra|ie)[\/:]([\d.]+)/) || [])[1];
        return b
    }();
    initOptions(options);

    function initOptions(options) {
        options = options || {};
        if (options.wrapping)
            wrapping = options.wrapping;
        else {
            options.serverdomain = options.serverdomain || "ads.adk2.com";
            options.size = options.size || "800x600";
            options.ci = "3";
            var arr = [],
                excluded = ["serverdomain", "numOfTimes", "duration", "period"];
            for (var p in options)
                options.hasOwnProperty(p) && options[p].toString() && excluded.indexOf(p) === -1 && arr.push(p + "=" + encodeURIComponent(options[p]));
            url = "http://" + options.serverdomain + "/player.html?rt=popunder&" + arr.join("&")
        }
        if (options.size) {
            size = options.size.split("x");
            options.width = size[0];
            options.height = size[1]
        }
        if (options.frequency) {
            frequency = /([0-9]+)\/([0-9]+)(\w)/.exec(options.frequency);
            options.numOfTimes = +frequency[1];
            options.duration = +frequency[2];
            options.period = ({
                m: "minute",
                h: "hour",
                d: "day"
            })[frequency[3].toLowerCase()]
        }
        if (options.period)
            switch (options.period.toLowerCase()) {
                case "minute":
                    expires = options.duration * 60 * 1e3;
                    break;
                case "hour":
                    expires = options.duration * 60 * 60 * 1e3;
                    break;
                case "day":
                    expires = options.duration * 24 * 60 * 60 * 1e3
            }
        posX = typeof options.left != "undefined" ? options.left.toString() : window.screenX;
        posY = typeof options.top != "undefined" ? options.top.toString() : window.screenY;
        numberOfTimes = options.numOfTimes
    }

    function getCookie(name) {
        try {
            var parts = document.cookie.split(name + "=");
            if (parts.length == 2)
                return unescape(parts.pop().split(";").shift()).split("|")
        } catch (err) {}
    }

    function setCookie(value, expiresDate) {
        expiresDate = cookie[1] || expiresDate.toGMTString();
        document.cookie = cookieName + "=" + escape(value + "|" + expiresDate) + ";expires=" + expiresDate + ";path=/"
    }

    function addEvent(listenerEvent) {
        if (document.addEventListener)
            document.addEventListener("click", listenerEvent, false);
        else
            document.attachEvent("onclick", listenerEvent)
    }

    function removeEvent(listenerEvent) {
        if (document.removeEventListener)
            document.removeEventListener("click", listenerEvent, false);
        else
            document.detachEvent("onclick", listenerEvent)
    }

    function isCapped() {
        cookie = getCookie(cookieName) || [];
        return !!numberOfTimes && +numberOfTimes <= +cookie[0]
    }

    function pop() {
        var features = "type=fullWindow, fullscreen, scrollbars=yes",
            listenerEvent = function() {
                var now, next;
                if (/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent))
                    if (mobilePopupDisabled)
                        return;
                if (isCapped())
                    return;
                if (browser.chrome && parseInt(browser.version.split(".")[0], 10) > 30 && adParams.openNewTab) {
                    now = new Date;
                    next = new Date(now.setTime(now.getTime() + expires));
                    setCookie((+cookie[0] || 0) + 1, next);
                    removeEvent(listenerEvent);
                    window.open("javascript:window.focus()", "_self", "");
                    simulateClick(url);
                    popunder = null
                } else
                    popunder = _parent.window.open(url, Math.random().toString(36).substring(7), features);
                if (wrapping) {
                    popunder.document.write("<html><head></head><body>" + unescape(wrapping || "") + "</body></html>");
                    popunder.document.body.style.margin = 0
                }
                if (popunder) {
                    now = new Date;
                    next = new Date(now.setTime(now.getTime() + expires));
                    setCookie((+cookie[0] || 0) + 1, next);
                    moveUnder();
                    removeEvent(listenerEvent)
                }
            };
        addEvent(listenerEvent)
    }
    var simulateClick = function(url) {
        var a = document.createElement("a"),
            u = !url ? "data:text/html,<script>window.close();<\/script>;" : url,
            evt = document.createEvent("MouseEvents");
        a.href = u;
        document.body.appendChild(a);
        evt.initMouseEvent("click", true, true, window, 0, 0, 0, 0, 0, true, false, false, true, 0, null);
        a.dispatchEvent(evt);
        a.parentNode.removeChild(a)
    };

    function moveUnder() {
        try {
            popunder.blur();
            popunder.opener.window.focus();
            window.self.window.focus();
            window.focus();
            if (browser.firefox)
                openCloseWindow();
            else if (browser.webkit)
                openCloseTab();
            else
                browser.msie && setTimeout(function() {
                    popunder.blur();
                    popunder.opener.window.focus();
                    window.self.window.focus();
                    window.focus()
                }, 1e3)
        } catch (e) {}
    }

    function openCloseWindow() {
        var tmp = popunder.window.open("about:blank");
        tmp.focus();
        tmp.close();
        setTimeout(function() {
            try {
                tmp = popunder.window.open("about:blank");
                tmp.focus();
                tmp.close()
            } catch (e) {}
        }, 1)
    }

    function openCloseTab() {
        var ghost = document.createElement("a"),
            clk;
        document.getElementsByTagName("body")[0].appendChild(ghost);
        clk = document.createEvent("MouseEvents");
        clk.initMouseEvent("click", false, true, window, 0, 0, 0, 0, 0, true, false, false, true, 0, null);
        ghost.dispatchEvent(clk);
        ghost.parentNode.removeChild(ghost);
        window.open("about:blank", "PopHelper").close()
    }
    pop()
})(adParams)

What's the difference between a mock & stub?

A Mock is just testing behaviour, making sure certain methods are called. A Stub is a testable version (per se) of a particular object.

What do you mean an Apple way?

Get week day name from a given month, day and year individually in SQL Server

I used

select
case
when (extract (weekday from DATE)=0) then 'Sunday'

and so on...

0 Sunday, 1 Monday...

Setting different color for each series in scatter plot on matplotlib

You can always use the plot() function like so:

import matplotlib.pyplot as plt

import numpy as np

x = np.arange(10)
ys = [i+x+(i*x)**2 for i in range(10)]
plt.figure()
for y in ys:
    plt.plot(x, y, 'o')
plt.show()

plot as scatter but changes colors

.NET unique object identifier

.NET 4 and later only

Good news, everyone!

The perfect tool for this job is built in .NET 4 and it's called ConditionalWeakTable<TKey, TValue>. This class:

  • can be used to associate arbitrary data with managed object instances much like a dictionary (although it is not a dictionary)
  • does not depend on memory addresses, so is immune to the GC compacting the heap
  • does not keep objects alive just because they have been entered as keys into the table, so it can be used without making every object in your process live forever
  • uses reference equality to determine object identity; moveover, class authors cannot modify this behavior so it can be used consistently on objects of any type
  • can be populated on the fly, so does not require that you inject code inside object constructors

Configuring Git over SSH to login once

Add a single line AddKeysToAgent yes on the top of the .ssh/config file. Ofcourse ssh-agent must be running beforehand. If its not running ( check by prep ssh-agent ) , then simply run it eval $(ssh-agent)

Now, the key is loaded systemwide into the memory and you dont have to type in the passphrase again.

The source of the solution is https://askubuntu.com/questions/362280/enter-ssh-passphrase-once/853578#853578

Bootstrap 3.0 - Fluid Grid that includes Fixed Column Sizes

UPDATE 2014-11-14: The solution below is too old, I recommend using flex box layout method. Here is a overview: http://learnlayout.com/flexbox.html


My solution

html

<li class="grid-list-header row-cw row-cw-msg-list ...">
  <div class="col-md-1 col-cw col-cw-name">
  <div class="col-md-1 col-cw col-cw-keyword">
  <div class="col-md-1 col-cw col-cw-reply">
  <div class="col-md-1 col-cw col-cw-action">
</li>

<li class="grid-list-item row-cw row-cw-msg-list ...">
  <div class="col-md-1 col-cw col-cw-name">
  <div class="col-md-1 col-cw col-cw-keyword">
  <div class="col-md-1 col-cw col-cw-reply">
  <div class="col-md-1 col-cw col-cw-action">
</li>

scss

.row-cw {
  position: relative;
}

.col-cw {
  position: absolute;
  top: 0;
}


.ir-msg-list {

  $col-reply-width: 140px;
  $col-action-width: 130px;

  .row-cw-msg-list {
    padding-right: $col-reply-width + $col-action-width;
  }

  .col-cw-name {
    width: 50%;
  }

  .col-cw-keyword {
    width: 50%;
  }

  .col-cw-reply {
    width: $col-reply-width;
    right: $col-action-width;
  }

  .col-cw-action {
    width: $col-action-width;
    right: 0;
  }
}

Without modify too much bootstrap layout code.


Update (not from OP): adding code snippet below to facilitate understanding of this answer. But it doesn't seem to work as expected.

_x000D_
_x000D_
ul {_x000D_
  list-style: none;_x000D_
}_x000D_
.row-cw {_x000D_
  position: relative;_x000D_
  height: 20px;_x000D_
}_x000D_
.col-cw {_x000D_
  position: absolute;_x000D_
  top: 0;_x000D_
  background-color: rgba(150, 150, 150, .5);_x000D_
}_x000D_
.row-cw-msg-list {_x000D_
  padding-right: 270px;_x000D_
}_x000D_
.col-cw-name {_x000D_
  width: 50%;_x000D_
  background-color: rgba(150, 0, 0, .5);_x000D_
}_x000D_
.col-cw-keyword {_x000D_
  width: 50%;_x000D_
  background-color: rgba(0, 150, 0, .5);_x000D_
}_x000D_
.col-cw-reply {_x000D_
  width: 140px;_x000D_
  right: 130px;_x000D_
  background-color: rgba(0, 0, 150, .5);_x000D_
}_x000D_
.col-cw-action {_x000D_
  width: 130px;_x000D_
  right: 0;_x000D_
  background-color: rgba(150, 150, 0, .5);_x000D_
}
_x000D_
<ul class="ir-msg-list">_x000D_
  <li class="grid-list-header row-cw row-cw-msg-list">_x000D_
    <div class="col-md-1 col-cw col-cw-name">name</div>_x000D_
    <div class="col-md-1 col-cw col-cw-keyword">keyword</div>_x000D_
    <div class="col-md-1 col-cw col-cw-reply">reply</div>_x000D_
    <div class="col-md-1 col-cw col-cw-action">action</div>_x000D_
  </li>_x000D_
_x000D_
  <li class="grid-list-item row-cw row-cw-msg-list">_x000D_
    <div class="col-md-1 col-cw col-cw-name">name</div>_x000D_
    <div class="col-md-1 col-cw col-cw-keyword">keyword</div>_x000D_
    <div class="col-md-1 col-cw col-cw-reply">reply</div>_x000D_
    <div class="col-md-1 col-cw col-cw-action">action</div>_x000D_
  </li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

How to set a default row for a query that returns no rows?

Do you want to return a full row? Does the default row need to have default values or can it be an empty row? Do you want the default row to have the same column structure as the table in question?

Depending on your requirements, you might do something like this:

1) run the query and put results in a temp table (or table variable) 2) check to see if the temp table has results 3) if not, return an empty row by performing a select statement similar to this (in SQL Server):

select '' as columnA, '' as columnB, '' as columnC from #tempTable

Where columnA, columnB and columnC are your actual column names.

How to mention C:\Program Files in batchfile

Now that bash is out for windows 10, if you want to access program files from bash, you can do it like so: cd /mnt/c/Program\ Files.

How to add to an NSDictionary

Update version

Objective-C

Create:

NSDictionary *dictionary = @{@"myKey1": @7, @"myKey2": @5}; 

Change:

NSMutableDictionary *mutableDictionary = [dictionary mutableCopy];     //Make the dictionary mutable to change/add
mutableDictionary[@"myKey3"] = @3;

The short-hand syntax is called Objective-C Literals.

Swift

Create:

var dictionary = ["myKey1": 7, "myKey2": 5]

Change:

dictionary["myKey3"] = 3

Find value in an array

Thanks for replies.

I did like this:

puts 'find' if array.include?(value)

How to activate JMX on my JVM for access with jconsole?

I had this exact issue, and created a GitHub project for testing and figuring out the correct settings.

It contains a working Dockerfile with supporting scripts, and a simple docker-compose.yml for quick testing.

Please initialize the log4j system properly warning

The fix for me was to put "log4j.properties" into the "src" folder. It did not work in my package folder it has to be one up at the very root of source. Adding it to the build path which then moves it to the "Reference Libraries" also did not work.

To repeat: put log4j.properties at the root of your src folder.

my log4j.properties files has the following content which works on the latest version of Spring Tool Suite which is based on Eclipse.

# Configure logging for testing: optionally with log file
#log4j.rootLogger=INFO, stdout
log4j.rootLogger=WARN, stdout, logfile

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %p [%c] - %m%n

log4j.appender.logfile=org.apache.log4j.FileAppender
log4j.appender.logfile.File=target/spring.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d %p [%c] - %m%

find a minimum value in an array of floats

If min value in array, you can try like:

>>> mydict = {"a": -1.5, "b": -1000.44, "c": -3}
>>> min(mydict.values())
-1000.44

WebView and HTML5 <video>

A-M's is similar to what the BrowerActivity does. for FrameLayout.LayoutParams LayoutParameters = new FrameLayout.LayoutParams (768, 512);

I think we can use

FrameLayout.LayoutParams LayoutParameters = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.FILL_PARENT,
            FrameLayout.LayoutParams.FILL_PARENT) 

instead.

Another issue I met is if the video is playing, and user clicks the back button, next time, you go to this activity(singleTop one) and can not play the video. to fix this, I called the

try { 
    mCustomVideoView.stopPlayback();  
    mCustomViewCallback.onCustomViewHidden();
} catch(Throwable e) { //ignore }

in the activity's onBackPressed method.

Submitting HTML form using Jquery AJAX

If you add:

jquery.form.min.js

You can simply do this:

<script>
$('#myform').ajaxForm(function(response) {
  alert(response);
});

// this will register the AJAX for <form id="myform" action="some_url">
// and when you submit the form using <button type="submit"> or $('myform').submit(), then it will send your request and alert response
</script>

NOTE:

You could use simple $('FORM').serialize() as suggested in post above, but that will not work for FILE INPUTS... ajaxForm() will.

How to deploy a war file in JBoss AS 7?

open up console and navigate to bin folder and run

JBOSS_HOME/bin > stanalone.sh

Once it is up and running just copy past your war file in

standalone/deployments folder

Thats probably it for jboss 7.1

Freeze screen in chrome debugger / DevTools panel for popover inspection?

I tried the other solutions here, they work but I'm lazy so this is my solution

  1. hover over the element to trigger expanded state
  2. ctrl+shift+c
  3. hover over element again
  4. right click
  5. navigate to the debugger

by right clicking it no longer registers mouse event since a context menu pops up, so you can move the mouse away safely

CSS3 animate border color

If you need the transition to run infinitely, try the below example:

_x000D_
_x000D_
#box {_x000D_
  position: relative;_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  background-color: gray;_x000D_
  border: 5px solid black;_x000D_
  display: block;_x000D_
}_x000D_
_x000D_
#box:hover {_x000D_
  border-color: red;_x000D_
  animation-name: flash_border;_x000D_
  animation-duration: 2s;_x000D_
  animation-timing-function: linear;_x000D_
  animation-iteration-count: infinite;_x000D_
  -webkit-animation-name: flash_border;_x000D_
  -webkit-animation-duration: 2s;_x000D_
  -webkit-animation-timing-function: linear;_x000D_
  -webkit-animation-iteration-count: infinite;_x000D_
  -moz-animation-name: flash_border;_x000D_
  -moz-animation-duration: 2s;_x000D_
  -moz-animation-timing-function: linear;_x000D_
  -moz-animation-iteration-count: infinite;_x000D_
}_x000D_
_x000D_
@keyframes flash_border {_x000D_
  0% {_x000D_
    border-color: red;_x000D_
  }_x000D_
  50% {_x000D_
    border-color: black;_x000D_
  }_x000D_
  100% {_x000D_
    border-color: red;_x000D_
  }_x000D_
}_x000D_
_x000D_
@-webkit-keyframes flash_border {_x000D_
  0% {_x000D_
    border-color: red;_x000D_
  }_x000D_
  50% {_x000D_
    border-color: black;_x000D_
  }_x000D_
  100% {_x000D_
    border-color: red;_x000D_
  }_x000D_
}_x000D_
_x000D_
@-moz-keyframes flash_border {_x000D_
  0% {_x000D_
    border-color: red;_x000D_
  }_x000D_
  50% {_x000D_
    border-color: black;_x000D_
  }_x000D_
  100% {_x000D_
    border-color: red;_x000D_
  }_x000D_
}
_x000D_
<div id="box">roll over me</div>
_x000D_
_x000D_
_x000D_

Disable submit button when form invalid with AngularJS

Selected response is correct, but someone like me, may have issues with async validation with sending request to the server-side - button will be not disabled during given request processing, so button will blink, which looks pretty strange for the users.

To void this, you just need to handle $pending state of the form:

<form name="myForm">
  <input name="myText" type="text" ng-model="mytext" required />
  <button ng-disabled="myForm.$invalid || myForm.$pending">Save</button>
</form>

How do I set up CLion to compile and run?

I met some problems in Clion and finally, I solved them. Here is some experience.

  1. Download and install MinGW
  2. g++ and gcc package should be installed by default. Use the MinGW installation manager to install mingw32-libz and mingw32-make. You can open MinGW installation manager through C:\MinGW\libexec\mingw-get.exe This step is the most important step. If Clion cannot find make, C compiler and C++ compiler, recheck the MinGW installation manager to make every necessary package is installed.
  3. In Clion, open File->Settings->Build,Execution,Deployment->Toolchains. Set MinGW home as your local MinGW file.
  4. Start your "Hello World"!

How to draw rounded rectangle in Android UI?

I think, this is you exactly needed.

Here drawable(xml) file that creates rounded rectangle. round_rect_shape.xml

<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle" >

    <solid android:color="#ffffff" />

    <corners
        android:bottomLeftRadius="8dp"
        android:bottomRightRadius="8dp"
        android:topLeftRadius="8dp"
        android:topRightRadius="8dp" />

</shape>

Here layout file: my_layout.xml

<LinearLayout
    android:id="@+id/linearLayout1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/round_rect_shape"
    android:orientation="vertical"
    android:padding="5dp" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Something text"
        android:textAppearance="?android:attr/textAppearanceLarge"
        android:textColor="#ff0000" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <requestFocus />
    </EditText>
</LinearLayout>

-> In the above code, LinearLayout having the background(That is the key role to place to create rounded rectangle). So you can place any view like TextView, EditText... in that LinearLayout to see background as round rectangle for all.

Ubuntu says "bash: ./program Permission denied"

chmod u+x program_name. Then execute it.

If that does not work, copy the program from the USB device to a native volume on the system. Then chmod u+x program_name on the local copy and execute that.

Unix and Unix-like systems generally will not execute a program unless it is marked with permission to execute. The way you copied the file from one system to another (or mounted an external volume) may have turned off execute permission (as a safety feature). The command chmod u+x name adds permission for the user that owns the file to execute it.

That command only changes the permissions associated with the file; it does not change the security controls associated with the entire volume. If it is security controls on the volume that are interfering with execution (for example, a noexec option may be specified for a volume in the Unix fstab file, which says not to allow execute permission for files on the volume), then you can remount the volume with options to allow execution. However, copying the file to a local volume may be a quicker and easier solution.

Reading HTTP headers in a Spring REST controller

The error that you get does not seem to be related to the RequestHeader.

And you seem to be confusing Spring REST services with JAX-RS, your method signature should be something like:

@RequestMapping(produces = "application/json", method = RequestMethod.GET, value = "data")
@ResponseBody
public ResponseEntity<Data> getData(@RequestHeader(value="User-Agent") String userAgent, @RequestParam(value = "ID", defaultValue = "") String id) {
    // your code goes here
}

And your REST class should have annotations like:

@Controller
@RequestMapping("/rest/")


Regarding the actual question, another way to get HTTP headers is to insert the HttpServletRequest into your method and then get the desired header from there.

Example:

@RequestMapping(produces = "application/json", method = RequestMethod.GET, value = "data")
@ResponseBody
public ResponseEntity<Data> getData(HttpServletRequest request, @RequestParam(value = "ID", defaultValue = "") String id) {
    String userAgent = request.getHeader("user-agent");
}

Don't worry about the injection of the HttpServletRequest because Spring does that magic for you ;)

Disable scrolling when touch moving certain element

try overflow hidden on the thing you don't want to scroll while touch event is happening. e.g set overflow hidden on Start and set it back to auto on end.

Did you try it ? I'd be interested to know if this would work.

document.addEventListener('ontouchstart', function(e) {
    document.body.style.overflow = "hidden";
}, false);

document.addEventListener('ontouchmove', function(e) {
    document.body.style.overflow = "auto";
}, false);

How to make the script wait/sleep in a simple way in unity

With .Net 4.x you can use Task-based Asynchronous Pattern (TAP) to achieve this:

// .NET 4.x async-await
using UnityEngine;
using System.Threading.Tasks;
public class AsyncAwaitExample : MonoBehaviour
{
     private async void Start()
     {
        Debug.Log("Wait.");
        await WaitOneSecondAsync();
        DoMoreStuff(); // Will not execute until WaitOneSecond has completed
     }
    private async Task WaitOneSecondAsync()
    {
        await Task.Delay(TimeSpan.FromSeconds(1));
        Debug.Log("Finished waiting.");
    }
}

this is a feature to use .Net 4.x with Unity please see this link for description about it

and this link for sample project and compare it with coroutine

But becareful as documentation says that This is not fully replacement with coroutine

Swift - Integer conversion to Hours/Minutes/Seconds

Building upon Vadian's answer, I wrote an extension that takes a Double (of which TimeInterval is a type alias) and spits out a string formatted as time.

extension Double {
  func asString(style: DateComponentsFormatter.UnitsStyle) -> String {
    let formatter = DateComponentsFormatter()
    formatter.allowedUnits = [.hour, .minute, .second, .nanosecond]
    formatter.unitsStyle = style
    guard let formattedString = formatter.string(from: self) else { return "" }
    return formattedString
  }
}

Here are what the various DateComponentsFormatter.UnitsStyle options look like:

10000.asString(style: .positional)  // 2:46:40
10000.asString(style: .abbreviated) // 2h 46m 40s
10000.asString(style: .short)       // 2 hr, 46 min, 40 sec
10000.asString(style: .full)        // 2 hours, 46 minutes, 40 seconds
10000.asString(style: .spellOut)    // two hours, forty-six minutes, forty seconds
10000.asString(style: .brief)       // 2hr 46min 40sec

Changing datagridview cell color dynamically

This works for me

dataGridView1.Rows[rowIndex].Cells[columnIndex].Style.BackColor = Color.Red;

Multiline TextView in Android?

Below code can work for Single line and Multi-line textview

isMultiLine = If true then Textview showing with Multi-line otherwise single line

    if (isMultiLine) {
        textView.setElegantTextHeight(true);
        textView.setInputType(InputType.TYPE_TEXT_FLAG_MULTI_LINE);
        textView.setSingleLine(false);
        
    } else {
        textView.setSingleLine(true);
        textView.setEllipsize(TextUtils.TruncateAt.END);
    }

Java correct way convert/cast object to Double

new Double(object.toString());

But it seems weird to me that you're going from an Object to a Double. You should have a better idea what class of object you're starting with before attempting a conversion. You might have a bit of a code quality problem there.

Note that this is a conversion, not casting.

How can I access Oracle from Python?

In addition to the Oracle instant client, you may also need to install the Oracle ODAC components and put the path to them into your system path. cx_Oracle seems to need access to the oci.dll file that is installed with them.

Also check that you get the correct version (32bit or 64bit) of them that matches your: python, cx_Oracle, and instant client versions.

What are enums and why are they useful?

As for me to make the code readable in future the most useful aplyable case of enumeration is represented in next snippet:

public enum Items {
    MESSAGES, CHATS, CITY_ONLINE, FRIENDS, PROFILE, SETTINGS, PEOPLE_SEARCH, CREATE_CHAT
}

@Override
public boolean onCreateOptionsMenu(Menu menuPrm) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menuPrm);
    View itemChooserLcl;
    for (int i = 0; i < menuPrm.size(); i++) {
        MenuItem itemLcl  = menuPrm.getItem(i);
            itemChooserLcl = itemLcl.getActionView();
            if (itemChooserLcl != null) {
                 //here Im marking each View' tag by enume values:
                itemChooserLcl.setTag(Items.values()[i]);
                itemChooserLcl.setOnClickListener(drawerMenuListener);
            }
        }
    return true;
}
private View.OnClickListener drawerMenuListener=new View.OnClickListener() {
    @Override
    public void onClick(View v) {
        Items tagLcl= (Items) v.getTag();
        switch (tagLcl){
            case MESSAGES: ;
            break;
            case CHATS : ;
            break;
            case CITY_ONLINE : ;
            break;
            case FRIENDS : ;
            break;
            case  PROFILE: ;
            break;
            case  SETTINGS: ;
            break;
            case  PEOPLE_SEARCH: ;
            break;
            case  CREATE_CHAT: ;
            break;
        }
    }
};

Sending email with gmail smtp with codeigniter email library

Another option I have working, in a linux server with Postfix:

First, configure CI email to use your server's email system: eg, in email.php, for example

# alias to postfix in a typical Postfix server
$config['protocol'] = 'sendmail'; 
$config['mailpath'] = '/usr/sbin/sendmail'; 

Then configure your postfix to relay the mail to google (perhaps depending on the sender address). You'll probably need to put you user-password settings in /etc/postfix/sasl_passwd (docs)

This is much simpler (and less fragmente) if you have a linux box, already configured to send some/all of its outgoing emails to Google.

PHP - Get array value with a numeric index

$array = array('foo' => 'bar', 33 => 'bin', 'lorem' => 'ipsum');
$array = array_values($array);
echo $array[0]; //bar
echo $array[1]; //bin
echo $array[2]; //ipsum

How to generate random colors in matplotlib?

Based on Ali's and Champitoad's answer:

If you want to try different palettes for the same, you can do this in a few lines:

cmap=plt.cm.get_cmap(plt.cm.viridis,143)

^143 being the number of colours you're sampling

I picked 143 because the entire range of colours on the colormap comes into play here. What you can do is sample the nth colour every iteration to get the colormap effect.

n=20 for i,(x,y) in enumerate(points): plt.scatter(x,y,c=cmap(n*i))

Retrieving the text of the selected <option> in <select> element

You can use selectedIndex to retrieve the current selected option:

el = document.getElementById('elemId')
selectedText = el.options[el.selectedIndex].text

How to disable "prevent this page from creating additional dialogs"?

function alertWithoutNotice(message){
    setTimeout(function(){
        alert(message);
    }, 1000);
}

jquery function val() is not equivalent to "$(this).value="?

One thing you can do is this:

$(this)[0].value = "Something";

This allows jQuery to return the javascript object for that element, and you can bypass jQuery Functions.

Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?

If I understand correctly, what you want to do is to have a clean environment to be set up for DB involving integration tests.

My approach here would be to drop the whole schema and recreate it later.

Reasons:

  1. You probably already have a "create schema" script. Re-using it for test isolation is easy.
  2. Creating a schema is pretty quick.
  3. With that approach, it is pretty easy to set up your script to have each fixture create a NEW schema (with a temporary name), and then you can start running test-fixtures in parallel, making the slowest part of your test suite much faster.

JQuery ajax call default timeout value

As an aside, when trying to diagnose a similar bug I realised that jquery's ajax error callback returns a status of "timeout" if it failed due to a timeout.

Here's an example:

$.ajax({
    url: "/ajax_json_echo/",
    timeout: 500,
    error: function(jqXHR, textStatus, errorThrown) {
        alert(textStatus); // this will be "timeout"
    }
});

Here it is on jsfiddle.

Pandas index column title or name

df.index.name should do the trick.

Python has a dir function that let's you query object attributes. dir(df.index) was helpful here.

How to trigger Jenkins builds remotely and to pass parameters

In your Jenkins job configuration, tick the box named "This build is parameterized", click the "Add Parameter" button and select the "String Parameter" drop down value.

Now define your parameter - example:

Enter image description here

Now you can use your parameter in your job / build pipeline, example:

Enter image description here

Next to trigger the build with own/custom parameter, invoke the following URL (using either POST or GET):

http://JENKINS_SERVER_ADDRESS/job/YOUR_JOB_NAME/buildWithParameters?myparam=myparam_value

How can I stop redis-server?

Option 1: go to redis installation directory and navigate to src , in my case :

/opt/redis3/src/redis-cli -p 6379 shutdown

where 6379 is the default port.

Option 2: find redis process and kill

ps aux | grep redis-server

t6b3fg   22292  0.0  0.0 106360  1588 pts/0    S+   01:19   0:00 /bin/sh /sbin/service redis start
t6b3fg   22299  0.0  0.0  11340  1200 pts/0    S+   01:19   0:00 /bin/sh /etc/init.d/redis start

And Then initiate kill:

kill -9 22292

kill -9 22299

I'm using Centos 6.7 , x86_64

hope it helps

FIND_IN_SET() vs IN()

SELECT  name
FROM    orders,company
WHERE   orderID = 1
        AND companyID IN (attachedCompanyIDs)

attachedCompanyIDs is a scalar value which is cast into INT (type of companyID).

The cast only returns numbers up to the first non-digit (a comma in your case).

Thus,

companyID IN ('1,2,3') = companyID IN (CAST('1,2,3' AS INT)) = companyID IN (1)

In PostgreSQL, you could cast the string into array (or store it as an array in the first place):

SELECT  name
FROM    orders
JOIN    company
ON      companyID = ANY (('{' | attachedCompanyIDs | '}')::INT[])
WHERE   orderID = 1

and this would even use an index on companyID.

Unfortunately, this does not work in MySQL since the latter does not support arrays.

You may find this article interesting (see #2):

Update:

If there is some reasonable limit on the number of values in the comma separated lists (say, no more than 5), so you can try to use this query:

SELECT  name
FROM    orders
CROSS JOIN
        (
        SELECT  1 AS pos
        UNION ALL
        SELECT  2 AS pos
        UNION ALL
        SELECT  3 AS pos
        UNION ALL
        SELECT  4 AS pos
        UNION ALL
        SELECT  5 AS pos
        ) q
JOIN    company
ON      companyID = CAST(NULLIF(SUBSTRING_INDEX(attachedCompanyIDs, ',', -pos), SUBSTRING_INDEX(attachedCompanyIDs, ',', 1 - pos)) AS UNSIGNED)

Go back button in a page

You can either use:

<button onclick="window.history.back()">Back</button>

or..

<button onclick="window.history.go(-1)">Back</button>

The difference, of course, is back() only goes back 1 page but go() goes back/forward the number of pages you pass as a parameter, relative to your current page.

Date in to UTC format Java

Try this... Worked for me and printed 10/22/2013 01:37:56 AM Ofcourse this is your code only with little modifications.

final SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss");
sdf.setTimeZone(TimeZone.getTimeZone("UTC"));   // This line converts the given date into UTC time zone
final java.util.Date dateObj = sdf.parse("2013-10-22T01:37:56");

aRevisedDate = new SimpleDateFormat("MM/dd/yyyy KK:mm:ss a").format(dateObj);
System.out.println(aRevisedDate);

Jackson and generic type reference

'JavaType' works !! I was trying to unmarshall (deserialize) a List in json String to ArrayList java Objects and was struggling to find a solution since days.
Below is the code that finally gave me solution. Code:

JsonMarshallerUnmarshaller<T> {
    T targetClass;

    public ArrayList<T> unmarshal(String jsonString) {
        ObjectMapper mapper = new ObjectMapper();

        AnnotationIntrospector introspector = new JacksonAnnotationIntrospector();
        mapper.getDeserializationConfig()
            .withAnnotationIntrospector(introspector);

        mapper.getSerializationConfig()
            .withAnnotationIntrospector(introspector);
        JavaType type = mapper.getTypeFactory().
            constructCollectionType(
                ArrayList.class, 
                targetclass.getClass());

        try {
            Class c1 = this.targetclass.getClass();
            Class c2 = this.targetclass1.getClass();
            ArrayList<T> temp = (ArrayList<T>) 
                mapper.readValue(jsonString,  type);
            return temp ;
        } catch (JsonParseException e) {
            e.printStackTrace();
        } catch (JsonMappingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        return null ;
    }  
}

Using different Web.config in development and production environment

On one project where we had 4 environments (development, test, staging and production) we developed a system where the application selected the appropriate configuration based on the machine name it was deployed to.

This worked for us because:

  • administrators could deploy applications without involving developers (a requirement) and without having to fiddle with config files (which they hated);
  • machine names adhered to a convention. We matched names using a regular expression and deployed to multiple machines in an environment; and
  • we used integrated security for connection strings. This means we could keep account names in our config files at design time without revealing any passwords.

It worked well for us in this instance, but probably wouldn't work everywhere.

Remove accents/diacritics in a string in JavaScript

With ES2015/ES6 String.prototype.normalize(),

const str = "Crème Brulée"
str.normalize("NFD").replace(/[\u0300-\u036f]/g, "")
> "Creme Brulee"

Two things are happening here:

  1. normalize()ing to NFD Unicode normal form decomposes combined graphemes into the combination of simple ones. The è of Crème ends up expressed as e + `.
  2. Using a regex character class to match the U+0300 ? U+036F range, it is now trivial to globally get rid of the diacritics, which the Unicode standard conveniently groups as the Combining Diacritical Marks Unicode block.

See comment for performance testing.

Alternatively, if you just want sorting

Intl.Collator has sufficient support ~95% right now, a polyfill is also available here but I haven't tested it.

const c = new Intl.Collator();
["creme brulee", "crème brulée", "crame brulai", "crome brouillé",
"creme brulay", "creme brulfé", "creme bruléa"].sort(c.compare)
["crame brulai", "creme brulay", "creme bruléa", "creme brulee",
"crème brulée", "creme brulfé", "crome brouillé"]


["creme brulee", "crème brulée", "crame brulai", "crome brouillé"].sort((a,b) => a>b)
["crame brulai", "creme brulee", "crome brouillé", "crème brulée"]

Best GUI designer for eclipse?

'Jigloo' is a very cool GUI designer. It is not free for commercial use however. It auto-generates code and allows for custom editing of the code it creates.

http://www.cloudgarden.com/jigloo/

Java Long primitive type maximum limit

Ranges from -9,223,372,036,854,775,808 to +9,223,372,036,854,775,807.

It will start from -9,223,372,036,854,775,808

Long.MIN_VALUE.

Make install, but not to default directories?

It depends on the package. If the Makefile is generated by GNU autotools (./configure) you can usually set the target location like so:

./configure --prefix=/somewhere/else/than/usr/local

If the Makefile is not generated by autotools, but distributed along with the software, simply open it up in an editor and change it. The install target directory is probably defined in a variable somewhere.

Python JSON dump / append to .txt with each variable on new line

To avoid confusion, paraphrasing both question and answer. I am assuming that user who posted this question wanted to save dictionary type object in JSON file format but when the user used json.dump, this method dumped all its content in one line. Instead, he wanted to record each dictionary entry on a new line. To achieve this use:

with g as outfile:
  json.dump(hostDict, outfile,indent=2)

Using indent = 2 helped me to dump each dictionary entry on a new line. Thank you @agf. Rewriting this answer to avoid confusion.

An existing connection was forcibly closed by the remote host - WCF

I' ve got the same problem. My solution is this :

If you using LinQ2SQL in your project, Open your dbml file in Visual Studio and change Serialization Mode to "Unidirectional" on

CodeIgniter: How to get Controller, Action, URL information

Update

The answer was added was in 2015 and the following methods are deprecated now

$this->router->fetch_class();  in favour of  $this->router->class; 
$this->router->fetch_method(); in favour of  $this->router->method;

Hi you should use the following approach

$this->router->fetch_class(); // class = controller
$this->router->fetch_method(); // action

for this purpose but for using this you need to extend your hook from the CI_Controller and it works like a charm, you should not use uri segments

Best way to check if an PowerShell Object exist?

What all of these answers do not highlight is that when comparing a value to $null, you have to put $null on the left-hand side, otherwise you may get into trouble when comparing with a collection-type value. See: https://github.com/nightroman/PowerShellTraps/blob/master/Basic/Comparison-operators-with-collections/looks-like-object-is-null.ps1

$value = @(1, $null, 2, $null)
if ($value -eq $null) {
    Write-Host "$value is $null"
}

The above block is (unfortunately) executed. What's even more interesting is that in Powershell a $value can be both $null and not $null:

$value = @(1, $null, 2, $null)
if (($value -eq $null) -and ($value -ne $null)) {
    Write-Host "$value is both $null and not $null"
}

So it is important to put $null on the left-hand side to make these comparisons work with collections:

$value = @(1, $null, 2, $null)
if (($null -eq $value) -and ($null -ne $value)) {
    Write-Host "$value is both $null and not $null"
}

I guess this shows yet again the power of Powershell !

Changing the color of a clicked table row using jQuery

Here's a possible solution that will color the entire row for your table.

CSS

tr.highlighted td {
    background: red;
}

jQuery

$('#data tr').click(function(e) {
    $('#data tr').removeClass('highlighted');
    $(this).toggleClass('highlighted');   
});

Demo: http://jsfiddle.net/jrthib/HVw7E/2/

CSS3's border-radius property and border-collapse:collapse don't mix. How can I use border-radius to create a collapsed table with rounded corners?

I just wrote a crazy set of CSS for this that seems to work perfectly:

table {
  border-collapse: separate;
  border-spacing: 0;
  width: 100%;
}
table td,
table th {
  border-right: 1px solid #CCC;
  border-top: 1px solid #CCC;
  padding: 3px 5px;
  vertical-align: top;
}
table td:first-child,
table th:first-child {
  border-left: 1px solid #CCC;
}
table tr:last-child td,
table tr:last-child th {
  border-bottom: 1px solid #CCC;
}
table thead + tbody tr:first-child td {
  border-top: 0;
}
table thead td,
table th {
  background: #EDEDED;
}

/* complicated rounded table corners! */
table thead:first-child tr:last-child td:first-child {
  border-bottom-left-radius: 0;
}
table thead:first-child tr:last-child td:last-child {
  border-bottom-right-radius: 0;
}
table thead + tbody tr:first-child td:first-child {
  border-top-left-radius: 0;
}
table thead + tbody tr:first-child td:last-child {
  border-top-right-radius: 0;
}
table tr:first-child td:first-child,
table thead tr:first-child td:first-child {
  border-top-left-radius: 5px;
}
table tr:first-child td:last-child,
table thead tr:first-child td:last-child {
  border-top-right-radius: 5px;
}
table tr:last-child td:first-child,
table thead:last-child tr:last-child td:first-child {
  border-bottom-left-radius: 5px;
}
table tr:last-child td:last-child,
table thead:last-child tr:last-child td:last-child {
  border-bottom-right-radius: 5px;
}

/* end complicated rounded table corners !*/

Styling a disabled input with css only

Let's just say you have 3 buttons:

<input type="button" disabled="disabled" value="hello world">
<input type="button" disabled value="hello world">
<input type="button" value="hello world">

To style the disabled button you can use the following css:

input[type="button"]:disabled{
    color:#000;
}

This will only affect the button which is disabled.

To stop the color changing when hovering you can use this too:

input[type="button"]:disabled:hover{
    color:#000;
}

You can also avoid this by using a css-reset.

Types in MySQL: BigInt(20) vs Int(20)

As far as I know, there is only one small difference is when you are trying to insert value which is out of range.

In examples I'll use 401421228216, which is 101110101110110100100011101100010111000 (length 39 characters)

  • If you have INT(20) for system this means allocate in memory minimum 20 bits. But if you'll insert value that bigger than 2^20, it will be stored successfully, only if it's less then INT(32) -> 2147483647 (or 2 * INT(32) -> 4294967295 for UNSIGNED)

Example:

mysql> describe `test`;
+-------+------------------+------+-----+---------+-------+
| Field | Type             | Null | Key | Default | Extra |
+-------+------------------+------+-----+---------+-------+
| id    | int(20) unsigned | YES  |     | NULL    |       |
+-------+------------------+------+-----+---------+-------+
1 row in set (0,00 sec)

mysql> INSERT INTO `test` (`id`) VALUES (401421228216);
ERROR 1264 (22003): Out of range value for column 'id' at row 1

mysql> SET sql_mode = '';
Query OK, 0 rows affected, 1 warning (0,00 sec)

mysql> INSERT INTO `test` (`id`) VALUES (401421228216);
Query OK, 1 row affected, 1 warning (0,06 sec)

mysql> SELECT * FROM `test`;
+------------+
| id         |
+------------+
| 4294967295 |
+------------+
1 row in set (0,00 sec)
  • If you have BIGINT(20) for system this means allocate in memory minimum 20 bits. But if you'll insert value that bigger than 2^20, it will be stored successfully, if it's less then BIGINT(64) -> 9223372036854775807 (or 2 * BIGINT(64) -> 18446744073709551615 for UNSIGNED)

Example:

mysql> describe `test`;
+-------+---------------------+------+-----+---------+-------+
| Field | Type                | Null | Key | Default | Extra |
+-------+---------------------+------+-----+---------+-------+
| id    | bigint(20) unsigned | YES  |     | NULL    |       |
+-------+---------------------+------+-----+---------+-------+
1 row in set (0,00 sec)

mysql> INSERT INTO `test` (`id`) VALUES (401421228216);
Query OK, 1 row affected (0,04 sec)

mysql> SELECT * FROM `test`;
+--------------+
| id           |
+--------------+
| 401421228216 |
+--------------+
1 row in set (0,00 sec)

What's the meaning of System.out.println in Java?

System is a class of java.lang package, out is an object of PrintStream class and also static data member of System class, print() and println() is an instance method of PrintStream class. it is provide soft output on console.

Excel VBA For Each Worksheet Loop

Try this more succinct code:

Sub LoopOverEachColumn()
    Dim WS As Worksheet
    For Each WS In ThisWorkbook.Worksheets
        ResizeColumns WS
    Next WS
End Sub

Private Sub ResizeColumns(WS As Worksheet)
    Dim StrSize As String
    Dim ColIter As Long
    StrSize = "20.14;9.71;35.86;30.57;23.57;21.43;18.43;23.86;27.43;36.71;30.29;31.14;31;41.14;33.86"
    For ColIter = 1 To 15
        WS.Columns(ColIter).ColumnWidth = Split(StrSize, ";")(ColIter - 1)
    Next ColIter
End Sub

If you want additional columns, just change 1 to 15 to 1 to X where X is the column index of the column you want, and append the column size you want to StrSize.

For example, if you want P:P to have a width of 25, just add ;25 to StrSize and change ColIter... to ColIter = 1 to 16.

Hope this helps.

How to center the elements in ConstraintLayout

just add

android:gravity="center"

and done :)

How can I make a button have a rounded border in Swift?

as aside tip make sure your button is not subclass of any custom class in story board , in such a case your code best place should be in custom class it self cause code works only out of the custom class if your button is subclass of the default UIButton class and outlet of it , hope this may help anyone wonders why corner radios doesn't apply on my button from code .

How to copy a file to a remote server in Python using SCP or SSH?

To do this in Python (i.e. not wrapping scp through subprocess.Popen or similar) with the Paramiko library, you would do something like this:

import os
import paramiko

ssh = paramiko.SSHClient() 
ssh.load_host_keys(os.path.expanduser(os.path.join("~", ".ssh", "known_hosts")))
ssh.connect(server, username=username, password=password)
sftp = ssh.open_sftp()
sftp.put(localpath, remotepath)
sftp.close()
ssh.close()

(You would probably want to deal with unknown hosts, errors, creating any directories necessary, and so on).

How to count the occurrence of certain item in an ndarray?

If you don't want to use numpy or a collections module you can use a dictionary:

d = dict()
a = [0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1]
for item in a:
    try:
        d[item]+=1
    except KeyError:
        d[item]=1

result:

>>>d
{0: 8, 1: 4}

Of course you can also use an if/else statement. I think the Counter function does almost the same thing but this is more transparant.

TCPDF not render all CSS properties

Since version 5.7 TCPDF includes support for CSS borders. Margins, padding and float are not yet supported. Check the TCPDF website at http://www.tcpdf.org and consult the official forum for further information.

How can I write text on a HTML5 canvas element?

Canvas text support is actually pretty good - you can control font, size, color, horizontal alignment, vertical alignment, and you can also get text metrics to get the text width in pixels. In addition, you can also use canvas transforms to rotate, stretch and even invert text.

Javascript: Easier way to format numbers?

There's the NUMBERFORMATTER jQuery plugin, details below:

https://code.google.com/p/jquery-numberformatter/

From the above link:

This plugin is a NumberFormatter plugin. Number formatting is likely familiar to anyone who's worked with server-side code like Java or PHP and who has worked with internationalization.

EDIT: Replaced the link with a more direct one.

$(document).ready(function() is not working

Use:

jQuery(document).ready(function($){
    // code where you can use $ thanks to the parameter
});

Or its shorter version:

jQuery(function($){
    // code where you can use $ thanks to the parameter
});

Why do I have to define LD_LIBRARY_PATH with an export every time I run my application?

You could add in your code a call system with the new definition:

sprintf(newdef,"export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:%s:%s",ld1,ld2);
system(newdef);

But, I don't know it that is the rigth solution but it works.

Regards

Run php function on button click

You can use isset().

<form method="post">
    <input type="submit" name="test" id="test" value="RUN" />

</form>

<?php

function testfun()
{
   echo "Your test function on button click is working";
}

if(isset($_POST('submit')))
{
   testfun();
}

?>

Using Java to pull data from a webpage?

The Basics

Look at these to build a solution more or less from scratch:

The Easily Glued-Up and Stitched-Up Stuff

You always have the option of calling external tools from Java using the exec() and similar methods. For instance, you could use wget, or cURL.

The Hardcore Stuff

Then if you want to go into more fully-fledged stuff, thankfully the need for automated web-testing as given us very practical tools for this. Look at:

Some other libs are purposefully written with web-scraping in mind:

Some Workarounds

Java is a language, but also a platform, with many other languages running on it. Some of which integrate great syntactic sugar or libraries to easily build scrapers.

Check out:

If you know of a great library for Ruby (JRuby, with an article on scraping with JRuby and HtmlUnit) or Python (Jython) or you prefer these languages, then give their JVM ports a chance.

Some Supplements

Some other similar questions:

Split a string by another string in C#

There is an overload of Split that takes strings.

"THExxQUICKxxBROWNxxFOX".Split(new [] { "xx" }, StringSplitOptions.None);

You can use either of these StringSplitOptions

  • None - The return value includes array elements that contain an empty string
  • RemoveEmptyEntries - The return value does not include array elements that contain an empty string

So if the string is "THExxQUICKxxxxBROWNxxFOX", StringSplitOptions.None will return an empty entry in the array for the "xxxx" part while StringSplitOptions.RemoveEmptyEntries will not.

Entity Framework Code First - two Foreign Keys from same table

It's also possible to specify the ForeignKey() attribute on the navigation property:

[ForeignKey("HomeTeamID")]
public virtual Team HomeTeam { get; set; }
[ForeignKey("GuestTeamID")]
public virtual Team GuestTeam { get; set; }

That way you don't need to add any code to the OnModelCreate method

How to POST JSON request using Apache HttpClient?

Apache HttpClient doesn't know anything about JSON, so you'll need to construct your JSON separately. To do so, I recommend checking out the simple JSON-java library from json.org. (If "JSON-java" doesn't suit you, json.org has a big list of libraries available in different languages.)

Once you've generated your JSON, you can use something like the code below to POST it

StringRequestEntity requestEntity = new StringRequestEntity(
    JSON_STRING,
    "application/json",
    "UTF-8");

PostMethod postMethod = new PostMethod("http://example.com/action");
postMethod.setRequestEntity(requestEntity);

int statusCode = httpClient.executeMethod(postMethod);

Edit

Note - The above answer, as asked for in the question, applies to Apache HttpClient 3.1. However, to help anyone looking for an implementation against the latest Apache client:

StringEntity requestEntity = new StringEntity(
    JSON_STRING,
    ContentType.APPLICATION_JSON);

HttpPost postMethod = new HttpPost("http://example.com/action");
postMethod.setEntity(requestEntity);

HttpResponse rawResponse = httpclient.execute(postMethod);

Is it possible to dynamically compile and execute C# code fragments?

Found this useful - ensures the compiled Assembly references everything you currently have referenced, since there's a good chance you wanted the C# you're compiling to use some classes etc in the code that's emitting this:

(string code is the dynamic C# being compiled)

        var refs = AppDomain.CurrentDomain.GetAssemblies();
        var refFiles = refs.Where(a => !a.IsDynamic).Select(a => a.Location).ToArray();
        var cSharp = (new Microsoft.CSharp.CSharpCodeProvider()).CreateCompiler();
        var compileParams = new System.CodeDom.Compiler.CompilerParameters(refFiles);
        compileParams.GenerateInMemory = true;
        compileParams.GenerateExecutable = false;

        var compilerResult = cSharp.CompileAssemblyFromSource(compileParams, code);
        var asm = compilerResult.CompiledAssembly;

In my case I was emitting a class, whose name was stored in a string, className, which had a single public static method named Get(), that returned with type StoryDataIds. Here's what calling that method looks like:

        var tempType = asm.GetType(className);
        var ids = (StoryDataIds)tempType.GetMethod("Get").Invoke(null, null);

Warning: Compilation can be surprisingly, extremely slow. A small, relatively simple 10-line chunk of code compiles at normal priority in 2-10 seconds on our relatively fast server. You should never tie calls to CompileAssemblyFromSource() to anything with normal performance expectations, like a web request. Instead, proactively compile code you need on a low-priority thread and have a way of dealing with code that requires that code to be ready, until it's had a chance to finish compiling. For example you could use it in a batch job process.

Eclipse DDMS error "Can't bind to local 8600 for debugger"

Maybe it's too late for an answer to this question but i think i have found a fix for it, what i noticed is within the info.plist file > JVMoption (Mac) with in the application package there is two version of java i.e it was showing "1.6*,1.7+" so i just changed it to "1.8*" which is my current java version and now its working for me

Android ADB devices unauthorized

Your app is being detected as some harmful program. Turn off "Verify apps over USB" option. It's in the same view as "USB debugging".

Getting all file names from a folder using C#

Take a look at Directory.GetFiles Method (String, String) (MSDN).

This method returns all the files as an array of filenames.

What are the uses of the exec command in shell scripts?

Just to augment the accepted answer with a brief newbie-friendly short answer, you probably don't need exec.

If you're still here, the following discussion should hopefully reveal why. When you run, say,

sh -c 'command'

you run a sh instance, then start command as a child of that sh instance. When command finishes, the sh instance also finishes.

sh -c 'exec command'

runs a sh instance, then replaces that sh instance with the command binary, and runs that instead.

Of course, both of these are useless in this limited context; you simply want

command

There are some fringe situations where you want the shell to read its configuration file or somehow otherwise set up the environment as a preparation for running command. This is pretty much the sole situation where exec command is useful.

#!/bin/sh
ENVIRONMENT=$(some complex task)
exec command

This does some stuff to prepare the environment so that it contains what is needed. Once that's done, the sh instance is no longer necessary, and so it's a (minor) optimization to simply replace the sh instance with the command process, rather than have sh run it as a child process and wait for it, then exit as soon as it finishes.

Similarly, if you want to free up as much resources as possible for a heavyish command at the end of a shell script, you might want to exec that command as an optimization.

If something forces you to run sh but you really wanted to run something else, exec something else is of course a workaround to replace the undesired sh instance (like for example if you really wanted to run your own spiffy gosh instead of sh but yours isn't listed in /etc/shells so you can't specify it as your login shell).

The second use of exec to manipulate file descriptors is a separate topic. The accepted answer covers that nicely; to keep this self-contained, I'll just defer to the manual for anything where exec is followed by a redirect instead of a command name.

ES6 class variable alternatives

If its only the cluttering what gives the problem in the constructor why not implement a initialize method that intializes the variables. This is a normal thing to do when the constructor gets to full with unnecessary stuff. Even in typed program languages like C# its normal convention to add an Initialize method to handle that.

How to create windows service from java jar?

The easiest solution I found for this so far is the Non-Sucking Service Manager

Usage would be

nssm install <servicename> "C:\Program Files\Java\jre7\java.exe" "-jar <path-to-jar-file>"

How do I handle the window close event in Tkinter?

I'd like to thank the answer by Apostolos for bringing this to my attention. Here's a much more detailed example for Python 3 in the year 2019, with a clearer description and example code.


Beware of the fact that destroy() (or not having a custom window closing handler at all) will destroy the window and all of its running callbacks instantly when the user closes it.

This can be bad for you, depending on your current Tkinter activity, and especially when using tkinter.after (periodic callbacks). You might be using a callback which processes some data and writes to disk... in that case, you obviously want the data writing to finish without being abruptly killed.

The best solution for that is to use a flag. So when the user requests window closing, you mark that as a flag, and then react to it.

(Note: I normally design GUIs as nicely encapsulated classes and separate worker threads, and I definitely don't use "global" (I use class instance variables instead), but this is meant to be a simple, stripped-down example to demonstrate how Tk abruptly kills your periodic callbacks when the user closes the window...)

from tkinter import *
import time

# Try setting this to False and look at the printed numbers (1 to 10)
# during the work-loop, if you close the window while the periodic_call
# worker is busy working (printing). It will abruptly end the numbers,
# and kill the periodic callback! That's why you should design most
# applications with a safe closing callback as described in this demo.
safe_closing = True

# ---------

busy_processing = False
close_requested = False

def close_window():
    global close_requested
    close_requested = True
    print("User requested close at:", time.time(), "Was busy processing:", busy_processing)

root = Tk()
if safe_closing:
    root.protocol("WM_DELETE_WINDOW", close_window)
lbl = Label(root)
lbl.pack()

def periodic_call():
    global busy_processing

    if not close_requested:
        busy_processing = True
        for i in range(10):
            print((i+1), "of 10")
            time.sleep(0.2)
            lbl["text"] = str(time.time()) # Will error if force-closed.
            root.update() # Force redrawing since we change label multiple times in a row.
        busy_processing = False
        root.after(500, periodic_call)
    else:
        print("Destroying GUI at:", time.time())
        try: # "destroy()" can throw, so you should wrap it like this.
            root.destroy()
        except:
            # NOTE: In most code, you'll wanna force a close here via
            # "exit" if the window failed to destroy. Just ensure that
            # you have no code after your `mainloop()` call (at the
            # bottom of this file), since the exit call will cause the
            # process to terminate immediately without running any more
            # code. Of course, you should NEVER have code after your
            # `mainloop()` call in well-designed code anyway...
            # exit(0)
            pass

root.after_idle(periodic_call)
root.mainloop()

This code will show you that the WM_DELETE_WINDOW handler runs even while our custom periodic_call() is busy in the middle of work/loops!

We use some pretty exaggerated .after() values: 500 milliseconds. This is just meant to make it very easy for you to see the difference between closing while the periodic call is busy, or not... If you close while the numbers are updating, you will see that the WM_DELETE_WINDOW happened while your periodic call "was busy processing: True". If you close while the numbers are paused (meaning that the periodic callback isn't processing at that moment), you see that the close happened while it's "not busy".

In real-world usage, your .after() would use something like 30-100 milliseconds, to have a responsive GUI. This is just a demonstration to help you understand how to protect yourself against Tk's default "instantly interrupt all work when closing" behavior.

In summary: Make the WM_DELETE_WINDOW handler set a flag, and then check that flag periodically and manually .destroy() the window when it's safe (when your app is done with all work).

PS: You can also use WM_DELETE_WINDOW to ask the user if they REALLY want to close the window; and if they answer no, you don't set the flag. It's very simple. You just show a messagebox in your WM_DELETE_WINDOW and set the flag based on the user's answer.

Pip freeze vs. pip list

The main difference is that the output of pip freeze can be dumped into a requirements.txt file and used later to re-construct the "frozen" environment.

In other words you can run: pip freeze > frozen-requirements.txt on one machine and then later on a different machine or on a clean environment you can do: pip install -r frozen-requirements.txt and you'll get the an identical environment with the exact same dependencies installed as you had in the original environment where you generated the frozen-requirements.txt.

How to convert C# nullable int to int

You can use the Value property for assignment.

v2 = v1.Value;

Clang vs GCC - which produces faster binaries?

The only way to determine this is to try it. FWIW I have seen some really good improvements using Apple's LLVM gcc 4.2 compared to the regular gcc 4.2 (for x86-64 code with quite a lot of SSE), but YMMV for different code bases. Assuming you're working with x86/x86-64 and that you really do care about the last few percent then you ought to try Intel's ICC too, as this can often beat gcc - you can get a 30 day evaluation license from intel.com and try it.

Angularjs simple file download causes router to redirect

https://docs.angularjs.org/guide/$location#html-link-rewriting

In cases like the following, links are not rewritten; instead, the browser will perform a full page reload to the original link.

  • Links that contain target element Example:
    <a href="/ext/link?a=b" target="_self">link</a>

  • Absolute links that go to a different domain Example:
    <a href="http://angularjs.org/">link</a>

  • Links starting with '/' that lead to a different base path when base is defined Example:
    <a href="/not-my-base/link">link</a>

So in your case, you should add a target attribute like so...

<a target="_self" href="example.com/uploads/asd4a4d5a.pdf" download="foo.pdf">

How to avoid HTTP error 429 (Too Many Requests) python

I've found out a nice workaround to IP blocking when scraping sites. It lets you run a Scraper indefinitely by running it from Google App Engine and redeploying it automatically when you get a 429.

Check out this article

How to execute a Ruby script in Terminal?

Open Terminal

cd to/the/program/location
ruby program.rb

or add #!/usr/bin/env ruby in the first of your program (script tell that this is executed using Ruby Interpreter)

Open Terminal

cd to/the/program/location
chmod 777 program.rb
./program.rb

pandas get column average/mean

you can use

df.describe() 

you will get basic statistics of the dataframe and to get mean of specific column you can use

df["columnname"].mean()

Mask output of `The following objects are masked from....:` after calling attach() function

It may be "better" to not use attach at all. On the plus side, you can save some typing if you use attach. Let's say your dataset is called mydata and you have variables called v1, v2, and v3. If you don't attach mydata, then you will type mean(mydata$v1) to get the mean of v1. If you do attach mydata, then you will type mean(v1) to get the mean of v1. But, if you don't detach the mydata dataset (every time), you'll get the message about the objects being masked going forward.

Solution 1 (assuming you want to attach):

  1. Use detach every time.
  2. See Dan Tarr's response if you already have the data attached (and it may be in the global environment several times). Then, in the future, use detach every time.

Solution 2

Don't use attach. Instead, include the dataset name every time you refer to a variable. The form is mydata$v1 (name of data set, dollar sign, name of variable).

As for me, I used solution 1 a lot in the past, but I've moved to solution 2. It's a bit more typing in the beginning, but if you are going to use the code multiple times, it just seems cleaner.

How do I perform HTML decoding/encoding using Python/Django?

Even though this is a really old question, this may work.

Django 1.5.5

In [1]: from django.utils.text import unescape_entities
In [2]: unescape_entities('&lt;img class=&quot;size-medium wp-image-113&quot; style=&quot;margin-left: 15px;&quot; title=&quot;su1&quot; src=&quot;http://blah.org/wp-content/uploads/2008/10/su1-300x194.jpg&quot; alt=&quot;&quot; width=&quot;300&quot; height=&quot;194&quot; /&gt;')
Out[2]: u'<img class="size-medium wp-image-113" style="margin-left: 15px;" title="su1" src="http://blah.org/wp-content/uploads/2008/10/su1-300x194.jpg" alt="" width="300" height="194" />'

jQuery - Increase the value of a counter when a button is clicked

You cannot use ++ on something which is not a variable, this would be the closest you can get:

$('#counter').html(function(i, val) { return +val+1 });

jQuery's html() method can get and set the HTML value of an element. If passed a function it can update the HTML based upon the existing value. So in the context of your code:

$("#update").click(function() {
    $('#counter').html(function(i, val) { return +val+1 });
}

DEMO: http://jsfiddle.net/marcuswhybrow/zRX2D/2/

When it comes to synchronising your counter on the page, with the counter value in your database, never trust the client! You send either an increment or decrement signal to you server side script, rather than a continuous value such as 10, or 23.

However you could send an AJAX request to the server when you change the HTML of your counter:

$("#update").click(function() {
    $('#counter').html(function(i, val) {
        $.ajax({
            url: '/path/to/script/',
            type: 'POST',
            data: {increment: true},
            success: function() { alert('Request has returned') }
        });
        return +val+1;
    });
}

Android camera android.hardware.Camera deprecated

Now we have to use android.hardware.camera2 as android.hardware.Camera is deprecated which will only work on API >23 FlashLight

   public class MainActivity extends AppCompatActivity {

     Button button;

     Boolean light=true;

     CameraDevice cameraDevice;

     private CameraManager cameraManager;

     private CameraCharacteristics cameraCharacteristics;

     String cameraId;

     @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        button=(Button)findViewById(R.id.button);
        cameraManager = (CameraManager) 
        getSystemService(Context.CAMERA_SERVICE);
        try {
          cameraId = cameraManager.getCameraIdList()[0];
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if(light){
                    try {

                        cameraManager.setTorchMode(cameraId,true);
                    } catch (CameraAccessException e) {
                        e.printStackTrace();
                    }

                    light=false;}
                    else {

                    try {

                      cameraManager.setTorchMode(cameraId,false);
                    } catch (CameraAccessException e) {
                        e.printStackTrace();
                    }


                    light=true;
                    }


            }
        });
    }
}

How do I programmatically "restart" an Android app?

Mikepenz's Alternative Answer needed some changes in my case. https://stackoverflow.com/a/22345538/12021422 Major Credits to Mikepenz's Answer which I could modify.

Here is the Plug and Play static function that worked for me.

Just pass the Context of Application and this function will handle the restart.

    public static void doRestart(Context c) {
        try {
            // check if the context is given
            if (c != null) {
                // fetch the package manager so we can get the default launch activity
                // (you can replace this intent with any other activity if you want
                PackageManager pm = c.getPackageManager();
                // check if we got the PackageManager
                if (pm != null) {
                    // create the intent with the default start activity for your application
                    Intent mStartActivity = pm.getLaunchIntentForPackage(c.getPackageName());
                    if (mStartActivity != null) {
                        mStartActivity.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                        
                        c.getApplicationContext().startActivity(mStartActivity);
                        // kill the application
                        System.exit(0);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
            Log.e("restart", "Could not Restart");
        }
    }