Programs & Examples On #Render

Rendering is the process of generating an image from a model (or models in what collectively could be called a scene file), by means of computer programs.

How to Call a Function inside a Render in React/Jsx

_x000D_
_x000D_
class App extends React.Component {_x000D_
  _x000D_
  buttonClick(){_x000D_
    console.log("came here")_x000D_
    _x000D_
  }_x000D_
  _x000D_
  subComponent() {_x000D_
    return (<div>Hello World</div>);_x000D_
  }_x000D_
  _x000D_
  render() {_x000D_
    return ( _x000D_
      <div className="patient-container">_x000D_
          <button onClick={this.buttonClick.bind(this)}>Click me</button>_x000D_
          {this.subComponent()}_x000D_
       </div>_x000D_
     )_x000D_
  }_x000D_
  _x000D_
_x000D_
_x000D_
}_x000D_
_x000D_
ReactDOM.render(<App/>, document.getElementById('app'));
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>_x000D_
<div id="app"></div>
_x000D_
_x000D_
_x000D_

it depends on your need, u can use either this.renderIcon() or bind this.renderIcon.bind(this)

UPDATE

This is how you call a method outside the render.

buttonClick(){
    console.log("came here")
}

render() {
   return (
       <div className="patient-container">
          <button onClick={this.buttonClick.bind(this)}>Click me</button>
       </div>
   );
}

The recommended way is to write a separate component and import it.

Scroll to the top of the page after render in react.js

All the solutions talk about adding the scroll on componentDidMount or componentDidUpdate but with the DOM.

I did all of that and didn't worked.

So, figured out some other way that works just fine for me.

Added componentDidUpdate() { window.scrollTo(0, 0) } on the header, that mine is out of the <Switch></Switch> element. Just free in the app. Works.

I also found about some ScrollRestoration thing, but I'm lazy now. And for now going to keep it the "DidUpdate" way.

Django - Reverse for '' not found. '' is not a valid view function or pattern name

Give the same name in urls.py

 path('detail/<int:id>', views.detail, name="detail"),

Render HTML to an image

This is what I did.

Note: Please check App.js for the code.

Link to source code

If you liked it, you can drop a star.??

Update:

import * as htmlToImage from 'html-to-image';
import download from 'downloadjs';

import logo from './logo.svg';
import './App.css';

const App = () => {
  const onButtonClick = () => {
    var domElement = document.getElementById('my-node');
    htmlToImage.toJpeg(domElement)
      .then(function (dataUrl) {
        console.log(dataUrl);
        download(dataUrl, 'image.jpeg');
      })
      .catch(function (error) {
        console.error('oops, something went wrong!', error);
      });
  };
  return (
    <div className="App" id="my-node">
      <header className="App-header">
        <img src={logo} className="App-logo" alt="logo" />
        <p>
          Edit <code>src/App.js</code> and save to reload.
        </p>
        <a
          className="App-link"
          href="https://reactjs.org"
          target="_blank"
          rel="noopener noreferrer"
        >
          Learn React
        </a><br></br>
        <button onClick={onButtonClick}>Download as JPEG</button>
      </header>
    </div>
  );
}

export default App;

Find integer index of rows with NaN in pandas dataframe

Don't know if this is too late but you can use np.where to find the indices of non values as such:

indices = list(np.where(df['b'].isna()[0]))

How do I get into a Docker container's shell?

To bash into a running container, type this:

docker exec -t -i container_name /bin/bash

or

docker exec -ti container_name /bin/bash

or

docker exec -ti container_name sh

Split String into an array of String

You need a regular expression like "\\s+", which means: split whenever at least one whitespace is encountered. The full Java code is:

try {
    String[] splitArray = input.split("\\s+");
} catch (PatternSyntaxException ex) {
    // 
}

How do I horizontally center an absolute positioned element inside a 100% width div?

Its easy, just wrap it in a relative box like so:

<div class="relative">
 <div class="absolute">LOGO</div>
</div>

The relative box has a margin: 0 Auto; and, important, a width...

Using CookieContainer with WebClient class

Yes. IMHO, overriding GetWebRequest() is the best solution to WebClient's limited functionalty. Before I knew about this option, I wrote lots of really painful code at the HttpWebRequest layer because WebClient almost, but not quite, did what I needed. Derivation is much easier.

Another option is to use the regular WebClient class, but manually populate the Cookie header before making the request and then pull out the Set-Cookies header on the response. There are helper methods on the CookieContainer class which make creating and parsing these headers easier: CookieContainer.SetCookies() and CookieContainer.GetCookieHeader(), respectively.

I prefer the former approach since it's easier for the caller and requires less repetitive code than the second option. Also, the derivation approach works the same way for multiple extensibility scenarios (e.g. cookies, proxies, etc.).

How do I store an array in localStorage?

Another solution would be to write a wrapper that store the array like this:

localStorage.setItem('names_length', names.length);
localStorage.setItem('names_0', names[0]);
localStorage.setItem('names_1', names[1]);
localStorage.setItem('names_' + n, names[n]);

Removes the overhead of converting to JSON, but would be annoying if you need to remove elements, as you would have to re-index the array :)

How do I format date value as yyyy-mm-dd using SSIS expression builder?

Correct expression is

"source " + (DT_STR,4,1252)DATEPART( "yyyy" , getdate() ) + "-" +
RIGHT("0" + (DT_STR,4,1252)DATEPART( "mm" , getdate() ), 2) + "-" +
RIGHT("0" + (DT_STR,4,1252)DATEPART( "dd" , getdate() ), 2) +".CSV"

Java: How to insert CLOB into oracle database

Try this , there is no need to set its a CLOB

  public static void main(String[] args)
        {
        try{    

                    System.out.println("Opening db");

                    Class.forName("oracle.jdbc.driver.OracleDriver"); 
                    if(con==null)
                     con=DriverManager.getConnection("jdbc:oracle:thin:@192.9.200.103:1521: orcl","sas","sas");  
                    if(stmt==null)
                    stmt=con.createStatement();  


                    int res=9;

                    String usersSql = "{call Esme_Insertsmscdata(?,?,?,?,?)}";
                    CallableStatement stmt = con.prepareCall(usersSql);
            // THIS THE CLOB DATA  
            stmt.setString(1,"SS¶5268771¶00058711¶04192018¶SS¶5268771¶00058712¶04192018¶SS¶5268772¶00058713¶04192018¶SS¶5268772¶00058714¶04192018¶SS¶5268773¶00058715¶04192018¶SS¶5268773¶00058716¶04192018¶SS¶5268774¶00058717¶04192018¶SS¶5268774¶00058718¶04192018¶SS¶5268775¶00058719¶04192018¶SS¶5268775¶00058720¶04192018¶");     
                    stmt.setString(2, "bcvbcvb");
                    stmt.setString(3, String.valueOf("4522"));
                    stmt.setString(4, "42.25.632.25");
                    stmt.registerOutParameter(5,OracleTypes.NUMBER);    
                    stmt.execute();
                    res=stmt.getInt(5);
                    stmt.close();

                    System.out.println(res);




                    }
                    catch(Exception e)
                    { 

                         try 
                         {
                            con.close();
                        } catch (SQLException e1) {


                        }
                    }  
                }
    }

Nodejs cannot find installed module on Windows

For windows, everybody said you should set environment variables for nodejs and npm modules, but do you know why? For some modules, they have command line tool, after installed the module, there'are [module].cmd file in C:\Program Files\nodejs, and it's used for launch in window command. So if you don't add the path containing the cmd file to environment variables %PATH% , you won't launch them successfully through command window.

Calling javascript function in iframe

The first and foremost condition that needs to be met is that both the parent and iframe should belong to the same origin. Once that is done the child can invoke the parent using window.opener method and the parent can do the same for the child as mentioned above

Reading multiple Scanner inputs

If every input asks the same question, you should use a for loop and an array of inputs:

Scanner dd = new Scanner(System.in);
int[] vars = new int[3];

for(int i = 0; i < vars.length; i++) {
  System.out.println("Enter next var: ");
  vars[i] = dd.nextInt();
}

Or as Chip suggested, you can parse the input from one line:

Scanner in = new Scanner(System.in);
int[] vars = new int[3];

System.out.println("Enter "+vars.length+" vars: ");
for(int i = 0; i < vars.length; i++)
  vars[i] = in.nextInt();

You were on the right track, and what you did works. This is just a nicer and more flexible way of doing things.

Vertical align text in block element

li a {
width: 300px;
height: 100px;
display: table-cell;
vertical-align: middle;
margin: auto 0;
background: red;

}

Synchronous Requests in Node.js

Though asynchronous style may be the nature of node.js and generally you should not do this, there are some times you want to do this.

I'm writing a handy script to check an API and want not to mess it up with callbacks.

Javascript cannot execute synchronous requests, but C libraries can.

https://github.com/dhruvbird/http-sync

What is the difference between a deep copy and a shallow copy?

Breadth vs Depth; think in terms of a tree of references with your object as the root node.

Shallow:

Before Copy Shallow Copying Shallow Done

The variables A and B refer to different areas of memory, when B is assigned to A the two variables refer to the same area of memory. Later modifications to the contents of either are instantly reflected in the contents of other, as they share contents.

Deep:

Before Copy Deep Copying Deep Done

The variables A and B refer to different areas of memory, when B is assigned to A the values in the memory area which A points to are copied into the memory area to which B points. Later modifications to the contents of either remain unique to A or B; the contents are not shared.

How do I capture the output into a variable from an external process in PowerShell?

This thing worked for me:

$scriptOutput = (cmd /s /c $FilePath $ArgumentList)

Python: How exactly can you take a string, split it, reverse it and join it back together again?

Do you mean like this?

import string
astr='a(b[c])d'

deleter=string.maketrans('()[]','    ')
print(astr.translate(deleter))
# a b c  d
print(astr.translate(deleter).split())
# ['a', 'b', 'c', 'd']
print(list(reversed(astr.translate(deleter).split())))
# ['d', 'c', 'b', 'a']
print(' '.join(reversed(astr.translate(deleter).split())))
# d c b a

The remote host closed the connection. The error code is 0x800704CD

I too got this same error on my image handler that I wrote. I got it like 30 times a day on site with heavy traffic, managed to reproduce it also. You get this when a user cancels the request (closes the page or his internet connection is interrupted for example), in my case in the following row:

myContext.Response.OutputStream.Write(buffer, 0, bytesRead);

I can’t think of any way to prevent it but maybe you can properly handle this. Ex:

        try
        {
            …
            myContext.Response.OutputStream.Write(buffer, 0, bytesRead);
            …
        }catch (HttpException ex)
        {
            if (ex.Message.StartsWith("The remote host closed the connection."))
                ;//do nothing
            else
                //handle other errors
        }            
        catch (Exception e)
        {
            //handle other errors
        }
        finally
        {//close streams etc..
        }

"Primary Filegroup is Full" in SQL Server 2008 Standard for no apparent reason

Do one thing, go to properties of database select files and increase initial size of database and set primary filegroup as autoincremented. Restart sql server.

You will be able to use database as earlier.

How to pretty print XML from the command line?

You didn't mention a file, so I assume you want to provide the XML string as standard input on the command line. In that case, do the following:

$ echo '<root><foo a="b">lorem</foo><bar value="ipsum" /></root>' | xmllint --format -

What size should TabBar images be?

30x30 is points, which means 30px @1x, 60px @2x, not somewhere in-between. Also, it's not a great idea to embed the title of the tab into the image—you're going to have pretty poor accessibility and localization results like that.

Notepad++ incrementally replace

(Posting in case someone might have a use of it).

I was looking for a solution for a problem a bit more sophisticated than OP - replacing EVERY occurrence of something with the number by same thing with incremented number

E.g. Replacing something like this:

<row id="1" />
<row id="2" />
<row id="1" />
<row id="3" />
<row id="1" />

By this:

<row id="2" />
<row id="3" />
<row id="2" />
<row id="4" />
<row id="2" />

Couldnt find the solution online so I wrote my own script in groovy (a bit ugly but does the job):

 /**
 * <p> Finds words that matches template and increases them by 1.
 * '_' in word template represents number.
 *
 * <p> E.g. if template equals 'Row="_"', then:
 * ALL Row=0 will be replaced by Row="1"
 * All Row=1 will be replaced by Row="2"
 * <p> Warning - your find template might not work properly if _ is the last character of it
 * etc.
 * <p> Requirments:
 * - Original text does not contain tepmlate string
 * - Only numbers in non-disrupted sequence are incremented and replaced
 * (i.e. from example below, if Row=4 exists in original text, but Row=3 not, than Row=4 will NOT be 
 * replaced by Row=5)
 */
def replace_inc(String text, int startingIndex, String findTemplate) {
    assert findTemplate.contains('_') : 'search template needs to contain "_" placeholder'
    assert !(findTemplate.replaceFirst('_','').contains('_')) : 'only one "_" placeholder is allowed'
    assert !text.contains('_____') : 'input text should not contain "______" (5 underscores)'
    while (true) {
        findString = findTemplate.replace("_",(startingIndex).toString())
        if (!text.contains(findString)) break;
        replaceString = findTemplate.replace("_", "_____"+(++startingIndex).toString())
        text = text.replaceAll(findString, replaceString)
    }
    return text.replaceAll("_____","") // get rid of '_____' character
}

// input
findTemplate = 'Row="_"'
path = /C:\TEMP\working_copy.txt/
startingIndex = 0

// do stuff
f = new File(path)
outText = replace_inc(f.text,startingIndex,findTemplate)
println "Results \n: " + outText
f.withWriter { out -> out.println outText }
println "Results written to $f"

How to create a file in Ruby

Use:

File.open("out.txt", [your-option-string]) {|f| f.write("write your stuff here") }

where your options are:

  • r - Read only. The file must exist.
  • w - Create an empty file for writing.
  • a - Append to a file.The file is created if it does not exist.
  • r+ - Open a file for update both reading and writing. The file must exist.
  • w+ - Create an empty file for both reading and writing.
  • a+ - Open a file for reading and appending. The file is created if it does not exist.

In your case, 'w' is preferable.

OR you could have:

out_file = File.new("out.txt", "w")
#...
out_file.puts("write your stuff here")
#...
out_file.close

Show just the current branch in Git

Someone might find this (git show-branch --current) helpful. The current branch is shown with a * mark.

host-78-65-229-191:idp-mobileid user-1$ git show-branch --current
! [CICD-1283-pipeline-in-shared-libraries] feat(CICD-1283): Use latest version of custom release plugin.
 * [master] Merge pull request #12 in CORES/idp-mobileid from feature/fix-schema-name to master
--
+  [CICD-1283-pipeline-in-shared-libraries] feat(CICD-1283): Use latest version of custom release plugin.
+  [CICD-1283-pipeline-in-shared-libraries^] feat(CICD-1283): Used the renamed AWS pipeline.
+  [CICD-1283-pipeline-in-shared-libraries~2] feat(CICD-1283): Point to feature branches of shared libraries.
-- [master] Merge pull request #12 in CORES/idp-mobileid from feature/fix-schema-name to master

Why is Thread.Sleep so harmful

Sleep is used in cases where independent program(s) that you have no control over may sometimes use a commonly used resource (say, a file), that your program needs to access when it runs, and when the resource is in use by these other programs your program is blocked from using it. In this case, where you access the resource in your code, you put your access of the resource in a try-catch (to catch the exception when you can't access the resource), and you put this in a while loop. If the resource is free, the sleep never gets called. But if the resource is blocked, then you sleep for an appropriate amount of time, and attempt to access the resource again (this why you're looping). However, bear in mind that you must put some kind of limiter on the loop, so it's not a potentially infinite loop. You can set your limiting condition to be N number of attempts (this is what I usually use), or check the system clock, add a fixed amount of time to get a time limit, and quit attempting access if you hit the time limit.

Insert/Update/Delete with function in SQL Server

Yes, you can!))

Disclaimer: This is not a solution, it is more of a hack to test out something. User-defined functions cannot be used to perform actions that modify the database state.

I found one way to make INSERT, UPDATE or DELETE in function using xp_cmdshell.

So you need just to replace the code inside @sql variable.

CREATE FUNCTION [dbo].[_tmp_func](@orderID NVARCHAR(50))
RETURNS INT
AS
BEGIN
DECLARE @sql varchar(4000), @cmd varchar(4000)
SELECT @sql = 'INSERT INTO _ord (ord_Code) VALUES (''' + @orderID + ''') '
SELECT @cmd = 'sqlcmd -S ' + @@servername +
              ' -d ' + db_name() + ' -Q "' + @sql + '"'
EXEC master..xp_cmdshell @cmd, 'no_output'
RETURN 1
END

Checking the equality of two slices

If you have two []byte, compare them using bytes.Equal. The Golang documentation says:

Equal returns a boolean reporting whether a and b are the same length and contain the same bytes. A nil argument is equivalent to an empty slice.

Usage:

package main

import (
    "fmt"
    "bytes"
)

func main() {
    a := []byte {1,2,3}
    b := []byte {1,2,3}
    c := []byte {1,2,2}

    fmt.Println(bytes.Equal(a, b))
    fmt.Println(bytes.Equal(a, c))
}

This will print

true
false

What is the proper way to format a multi-line dict in Python?

Usually, if you have big python objects it's quite hard to format them. I personally prefer using some tools for that.

Here is python-beautifier - www.cleancss.com/python-beautify that instantly turns your data into customizable style.

Where/How to getIntent().getExtras() in an Android Fragment?

What I tend to do, and I believe this is what Google intended for developers to do too, is to still get the extras from an Intent in an Activity and then pass any extra data to fragments by instantiating them with arguments.

There's actually an example on the Android dev blog that illustrates this concept, and you'll see this in several of the API demos too. Although this specific example is given for API 3.0+ fragments, the same flow applies when using FragmentActivity and Fragment from the support library.

You first retrieve the intent extras as usual in your activity and pass them on as arguments to the fragment:

public static class DetailsActivity extends FragmentActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // (omitted some other stuff)

        if (savedInstanceState == null) {
            // During initial setup, plug in the details fragment.
            DetailsFragment details = new DetailsFragment();
            details.setArguments(getIntent().getExtras());
            getSupportFragmentManager().beginTransaction().add(
                    android.R.id.content, details).commit();
        }
    }
}

In stead of directly invoking the constructor, it's probably easier to use a static method that plugs the arguments into the fragment for you. Such a method is often called newInstance in the examples given by Google. There actually is a newInstance method in DetailsFragment, so I'm unsure why it isn't used in the snippet above...

Anyways, all extras provided as argument upon creating the fragment, will be available by calling getArguments(). Since this returns a Bundle, its usage is similar to that of the extras in an Activity.

public static class DetailsFragment extends Fragment {
    /**
     * Create a new instance of DetailsFragment, initialized to
     * show the text at 'index'.
     */
    public static DetailsFragment newInstance(int index) {
        DetailsFragment f = new DetailsFragment();

        // Supply index input as an argument.
        Bundle args = new Bundle();
        args.putInt("index", index);
        f.setArguments(args);

        return f;
    }

    public int getShownIndex() {
        return getArguments().getInt("index", 0);
    }

    // (other stuff omitted)

}

Rename Oracle Table or View

In order to rename a table in a different schema, try:

ALTER TABLE owner.mytable RENAME TO othertable;

The rename command (as in "rename mytable to othertable") only supports renaming a table in the same schema.

Find unique lines

uniq -u < file will do the job.

How to select last one week data from today's date

to select records for the last 7 days

WHERE Created_Date >= DATEADD(day, -7, GETDATE())

to select records for the current week

SET DATEFIRST 1 -- Define beginning of week as Monday
SELECT * FROM
WHERE CreatedDate >= DATEADD(day, 1 - DATEPART(dw, GETDATE()), CONVERT(DATE, GETDATE())) 
  AND CreatedDate <  DATEADD(day, 8 - DATEPART(dw, GETDATE()), CONVERT(DATE, GETDATE()))

if you want to select records for last week instead of the last 7 days

SET DATEFIRST 1 -- Define beginning of week as Monday
SELECT * FROM  
WHERE CreatedDate >= DATEADD(day, -(DATEPART(dw, GETDATE()) + 6), CONVERT(DATE, GETDATE())) 
  AND CreatedDate <  DATEADD(day, 1 - DATEPART(dw, GETDATE()), CONVERT(DATE, GETDATE()))

How can I create a temp file with a specific extension with .NET?

Guaranteed to be (statistically) unique:

string fileName = System.IO.Path.GetTempPath() + Guid.NewGuid().ToString() + ".csv"; 

(To quote from the wiki article on the probabilty of a collision:

...one's annual risk of being hit by a meteorite is estimated to be one chance in 17 billion [19], that means the probability is about 0.00000000006 (6 × 10-11), equivalent to the odds of creating a few tens of trillions of UUIDs in a year and having one duplicate. In other words, only after generating 1 billion UUIDs every second for the next 100 years, the probability of creating just one duplicate would be about 50%. The probability of one duplicate would be about 50% if every person on earth owns 600 million UUIDs

EDIT: Please also see JaredPar's comments.

SQL ORDER BY multiple columns

The results are ordered by the first column, then the second, and so on for as many columns as the ORDER BY clause includes. If you want any results sorted in descending order, your ORDER BY clause must use the DESC keyword directly after the name or the number of the relevant column.

Check out this Example

SELECT first_name, last_name, hire_date, salary 
FROM employee 
ORDER BY hire_date DESC,last_name ASC;

It will order in succession. Order the Hire_Date first, then LAST_NAME it by Hire_Date .

MySQL: Large VARCHAR vs. TEXT?

Varchar is for small data like email addresses, while Text is for much bigger data like news articles, Blob for binary data such as images.

The performance of Varchar is more powerful because it runs completely from memory, but this will not be the case if data is too big like varchar(4000) for example.

Text, on the other hand, does not stick to memory and is affected by disk performance, but you can avoid that by separating text data in a separate table and apply a left join query to retrieve text data.

Blob is much slower so use it only if you don't have much data like 10000 images which will cost 10000 records.

Follow these tips for maximum speed and performance:

  1. Use varchar for name, titles, emails

  2. Use Text for large data

  3. Separate text in different tables

  4. Use Left Join queries on an ID such as a phone number

  5. If you are going to use Blob apply the same tips as in Text

This will make queries cost milliseconds on tables with data >10 M and size up to 10GB guaranteed.

The located assembly's manifest definition does not match the assembly reference

I had a similar problem when attempting to update one DLL file of my web-site.

This error was occurring, when I simply copied this DLL file into bin folder over FTP.

I resolved this problem by:

  1. stopping the web-site;
  2. copying needed DLL file/DLL files;
  3. starting the web-site

Get time difference between two dates in seconds

Accurate and fast will give output in seconds:

 let startDate = new Date()
 let endDate = new Date("yyyy-MM-dd'T'HH:mm:ssZ");
 let seconds = Math.round((endDate.getTime() - startDate.getTime()) / 1000);

Sibling package imports

in your main file add this:

import sys
import os 
sys.path.append(os.path.abspath(os.path.join(__file__,mainScriptDepth)))

mainScriptDepth = the depth of the main file from the root of the project.

Here in your case mainScriptDepth = "../../".

Amazon Interview Question: Design an OO parking lot

public class ParkingLot 
{
    Vector<ParkingSpace> vacantParkingSpaces = null;
    Vector<ParkingSpace> fullParkingSpaces = null;

    int parkingSpaceCount = 0;

    boolean isFull;
    boolean isEmpty;

    ParkingSpace findNearestVacant(ParkingType type)
    {
        Iterator<ParkingSpace> itr = vacantParkingSpaces.iterator();

        while(itr.hasNext())
        {
            ParkingSpace parkingSpace = itr.next();

            if(parkingSpace.parkingType == type)
            {
                return parkingSpace;
            }
        }
        return null;
    }

    void parkVehicle(ParkingType type, Vehicle vehicle)
    {
        if(!isFull())
        {
            ParkingSpace parkingSpace = findNearestVacant(type);

            if(parkingSpace != null)
            {
                parkingSpace.vehicle = vehicle;
                parkingSpace.isVacant = false;

                vacantParkingSpaces.remove(parkingSpace);
                fullParkingSpaces.add(parkingSpace);

                if(fullParkingSpaces.size() == parkingSpaceCount)
                    isFull = true;

                isEmpty = false;
            }
        }
    }

    void releaseVehicle(Vehicle vehicle)
    {
        if(!isEmpty())
        {
            Iterator<ParkingSpace> itr = fullParkingSpaces.iterator();

            while(itr.hasNext())
            {
                ParkingSpace parkingSpace = itr.next();

                if(parkingSpace.vehicle.equals(vehicle))
                {
                    fullParkingSpaces.remove(parkingSpace);
                    vacantParkingSpaces.add(parkingSpace);

                    parkingSpace.isVacant = true;
                    parkingSpace.vehicle = null;

                    if(vacantParkingSpaces.size() == parkingSpaceCount)
                        isEmpty = true;

                    isFull = false;
                }
            }
        }
    }

    boolean isFull()
    {
        return isFull;
    }

    boolean isEmpty()
    {
        return isEmpty;
    }
}

public class ParkingSpace 
{
    boolean isVacant;
    Vehicle vehicle;
    ParkingType parkingType;
    int distance;
}

public class Vehicle 
{
    int num;
}

public enum ParkingType
{
    REGULAR,
    HANDICAPPED,
    COMPACT,
    MAX_PARKING_TYPE,
}

What is the difference between Integrated Security = True and Integrated Security = SSPI?

Many questions get answers if we use .Net Reflector to see the actual code of SqlConnection :) true and sspi are the same:

internal class DbConnectionOptions

...

internal bool ConvertValueToIntegratedSecurityInternal(string stringValue)
{
    if ((CompareInsensitiveInvariant(stringValue, "sspi") || CompareInsensitiveInvariant(stringValue, "true")) || CompareInsensitiveInvariant(stringValue, "yes"))
    {
        return true;
    }
}

...

EDIT 20.02.2018 Now in .Net Core we can see its open source on github! Search for ConvertValueToIntegratedSecurityInternal method:

https://github.com/dotnet/corefx/blob/fdbb160aeb0fad168b3603dbdd971d568151a0c8/src/System.Data.SqlClient/src/System/Data/Common/DbConnectionOptions.cs

Bootstrap 3, 4 and 5 .container-fluid with grid adding unwanted padding

Please find the actual css from Bootstrap

.container-fluid {
  padding-right: 15px;
  padding-left: 15px;
  margin-right: auto;
  margin-left: auto;
}
.row {
  margin-right: -15px;
  margin-left: -15px;
}

When you add a .container-fluid class, it adds a horizontal padding of 15px, and the same will be removed when you add a .row class as a child element by the negative margin set on row.

When should I write the keyword 'inline' for a function/method?

You still need to explicitly inline your function when doing template specialization (if specialization is in .h file)

How to create XML file with specific structure in Java

You can use the JDOM library in Java. Define your tags as Element objects, document your elements with Document Class, and build your xml file with SAXBuilder. Try this example:

//Root Element
Element root=new Element("CONFIGURATION");
Document doc=new Document();
//Element 1
Element child1=new Element("BROWSER");
//Element 1 Content
child1.addContent("chrome");
//Element 2
Element child2=new Element("BASE");
//Element 2 Content
child2.addContent("http:fut");
//Element 3
Element child3=new Element("EMPLOYEE");
//Element 3 --> In this case this element has another element with Content
child3.addContent(new Element("EMP_NAME").addContent("Anhorn, Irene"));

//Add it in the root Element
root.addContent(child1);
root.addContent(child2);
root.addContent(child3);
//Define root element like root
doc.setRootElement(root);
//Create the XML
XMLOutputter outter=new XMLOutputter();
outter.setFormat(Format.getPrettyFormat());
outter.output(doc, new FileWriter(new File("myxml.xml")));

Changing password with Oracle SQL Developer

One note for people who might not have the set password for sysdba or sys and regularly use a third party client. Here's some info about logging into command line sqlplus without a password that helped me. I am using fedora 21 by the way.

locate sqlplus

In my case, sqlplus is located here:

/u01/app/oracle/product/11.2.0/xe/config/scripts/sqlplus.sh

Now run

cd /u01/app/oracle/product/11.2.0/xe/config/scripts
./sqlplus.sh / as sysdba

Now you need to connect to database with your old credentials. You can find Oracle provided template in your output:

Use "connect username/password@XE" to connect to the database.

In my case I have user "oracle" with password "oracle" so my input looks like

connect oracle/oracle@XE

Done. Now type your new password twice. Then if you don't want your password to expire anymore you could run

ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;

Quickly getting to YYYY-mm-dd HH:MM:SS in Perl

Time::Piece (in core since Perl 5.10) also has a strftime function and by default overloads localtime and gmtime to return Time::Piece objects:

use Time::Piece;
print localtime->strftime('%Y-%m-%d');

or without the overridden localtime:

use Time::Piece (); 
print Time::Piece::localtime->strftime('%F %T');

How to use conditional breakpoint in Eclipse?

A way that might be more convenient: where you want a breakpoint, write a no-op if statement and set a breakpoint in its contents.

if(tablist[i].equalsIgnoreCase("LEADDELEGATES")) {
-->    int noop = 0; //don't do anything
}

(the breakpoint is represented by the arrow)

This way, the breakpoint only triggers if your condition is true. This could potentially be easier without that many pop-ups.

"X does not name a type" error in C++

You need to define MyMessageBox before User -- because User include object of MyMessageBox by value (and so compiler should know its size).

Also you'll need to forward declare User befor MyMessageBox -- because MyMessageBox include member of User* type.

Updating GUI (WPF) using a different thread

Here is a full example that updates UI textboxes

<Window x:Class="WpfThreading.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:WpfThreading"
    mc:Ignorable="d"
    Title="MainWindow" Height="450" Width="216.84">
<Grid Margin="0,0,2,0">
    <Button Content="Button" HorizontalAlignment="Left" Margin="10,10,0,0"
            VerticalAlignment="Top" Width="75" Click="Button_Click"/>
    <TextBox HorizontalAlignment="Left" Margin="10,35,0,10" TextWrapping="Wrap" Name="mtextBox" Width="87"   VerticalScrollBarVisibility="Auto"/>
    <TextBox HorizontalAlignment="Left" Margin="111,35,0,10" TextWrapping="Wrap" x:Name="mtextBox2" Width="87"   VerticalScrollBarVisibility="Auto"/>
</Grid></Window>

and in the code

public partial class MainWindow : Window
{
    public MainWindow()
    {
        InitializeComponent();
    }

    private void Button_Click(object sender, RoutedEventArgs e)
    {
        new Thread(DoSomething).Start();
        new Thread(DoSomething2).Start();
    }


    public void DoSomething()
    {
        for (int i = 0; i < 100; i++)
        {
            Dispatcher.BeginInvoke(new Action(() => {
                mtextBox.Text += $"{i.ToString()}{Environment.NewLine}";
            }), DispatcherPriority.SystemIdle);

            Thread.Sleep(100);
        }

    }

    public void DoSomething2()
    {
        for (int i = 100; i > 0; i--)
        {
            Dispatcher.BeginInvoke(new Action(() => {
                mtextBox2.Text += $"{i.ToString()}{Environment.NewLine}";
            }), DispatcherPriority.SystemIdle);

            Thread.Sleep(100);
        }

    }
}

Passing arguments to an interactive program non-interactively

You can put the data in a file and re-direct it like this:

$ cat file.sh
#!/bin/bash

read x
read y
echo $x
echo $y

Data for the script:

$ cat data.txt
2
3

Executing the script:

$ file.sh < data.txt
2
3

MS SQL 2008 - get all table names and their row counts in a DB

SELECT sc.name +'.'+ ta.name TableName
 ,SUM(pa.rows) RowCnt
 FROM sys.tables ta
 INNER JOIN sys.partitions pa
 ON pa.OBJECT_ID = ta.OBJECT_ID
 INNER JOIN sys.schemas sc
 ON ta.schema_id = sc.schema_id
 WHERE ta.is_ms_shipped = 0 AND pa.index_id IN (1,0)
 GROUP BY sc.name,ta.name
 ORDER BY SUM(pa.rows) DESC

See this:

Delete specified file from document directory

FreeGor version converted to Swift 3.0

 func removeOldFileIfExist() {
    let paths = NSSearchPathForDirectoriesInDomains(FileManager.SearchPathDirectory.documentDirectory, FileManager.SearchPathDomainMask.userDomainMask, true)
    if paths.count > 0 {
        let dirPath = paths[0]
        let fileName = "filename.jpg"
        let filePath = NSString(format:"%@/%@", dirPath, fileName) as String
        if FileManager.default.fileExists(atPath: filePath) {
            do {
                try FileManager.default.removeItem(atPath: filePath)
                print("User photo has been removed")
            } catch {
                print("an error during a removing")
            }
        }
    }
}

Converting NumPy array into Python List structure?

The numpy .tolist method produces nested lists if the numpy array shape is 2D.

if flat lists are desired, the method below works.

import numpy as np
from itertools import chain

a = [1,2,3,4,5,6,7,8,9]
print type(a), len(a), a
npa = np.asarray(a)
print type(npa), npa.shape, "\n", npa
npa = npa.reshape((3, 3))
print type(npa), npa.shape, "\n", npa
a = list(chain.from_iterable(npa))
print type(a), len(a), a`

What does ** (double star/asterisk) and * (star/asterisk) do for parameters?

* means receive variable arguments as tuple

** means receive variable arguments as dictionary

Used like the following:

1) single *

def foo(*args):
    for arg in args:
        print(arg)

foo("two", 3)

Output:

two
3

2) Now **

def bar(**kwargs):
    for key in kwargs:
        print(key, kwargs[key])

bar(dic1="two", dic2=3)

Output:

dic1 two
dic2 3

What's the difference between StaticResource and DynamicResource in WPF?

What is the main difference. Like memory or performance implications

The difference between static and dynamic resources comes when the underlying object changes. If your Brush defined in the Resources collection were accessed in code and set to a different object instance, Rectangle will not detect this change.

Static Resources retrieved once by referencing element and used for the lifetime of the resources. Whereas, DynamicResources retrieve every time they are used.

The downside of Dynamic resources is that they tend to decrease application performance.

Are there rules in WPF like "brushes are always static" and "templates are always dynamic" etc.?

The best practice is to use Static Resources unless there is a specific reason like you want to change resource in the code behind dynamically. Another example of instance in which you would want t to use dynamic resoruces include when you use the SystemBrushes, SystenFonts and System Parameters.

How to export all collections in MongoDB?

You can use mongo --eval 'printjson(db.getCollectionNames())' to get the list of collections and then do a mongoexport on all of them. Here is an example in ruby

  out = `mongo  #{DB_HOST}/#{DB_NAME} --eval "printjson(db.getCollectionNames())"`

  collections = out.scan(/\".+\"/).map { |s| s.gsub('"', '') }

  collections.each do |collection|
    system "mongoexport --db #{DB_NAME}  --collection #{collection}  --host '#{DB_HOST}' --out #{collection}_dump"
  end

Starting a shell in the Docker Alpine container

Nowadays, Alpine images will boot directly into /bin/sh by default, without having to specify a shell to execute:

$ sudo docker run -it --rm alpine  
/ # echo $0  
/bin/sh  

This is since the alpine image Dockerfiles now contain a CMD command, that specifies the shell to execute when the container starts: CMD ["/bin/sh"].

In older Alpine image versions (pre-2017), the CMD command was not used, since Docker used to create an additional layer for CMD which caused the image size to increase. This is something that the Alpine image developers wanted to avoid. In recent Docker versions (1.10+), CMD no longer occupies a layer, and so it was added to alpine images. Therefore, as long as CMD is not overridden, recent Alpine images will boot into /bin/sh.

For reference, see the following commit to the official Alpine Dockerfiles by Glider Labs:
https://github.com/gliderlabs/docker-alpine/commit/ddc19dd95ceb3584ced58be0b8d7e9169d04c7a3#diff-db3dfdee92c17cf53a96578d4900cb5b

Convert String to Date in MS Access Query

If you need to display all the records after 2014-09-01, add this to your query:

SELECT * FROM Events
WHERE Format(Events.DATE_TIME,'yyyy-MM-dd hh:mm:ss')  >= Format("2014-09-01 00:00:00","yyyy-MM-dd hh:mm:ss")

How do I escape ampersands in batch files?

From a cmd:

  • & is escaped like this: ^& (based on @Wael Dalloul's answer)
  • % does not need to be escaped

An example:

start http://www.google.com/search?client=opera^&rls=en^&q=escape+ampersand%20and%20percentage+in+cmd^&sourceid=opera^&ie=utf-8^&oe=utf-8

From a batch file

  • & is escaped like this: ^& (based on @Wael Dalloul's answer)
  • % is escaped like this: %% (based on the OPs update)

An example:

start http://www.google.com/search?client=opera^&rls=en^&q=escape+ampersand%%20and%%20percentage+in+batch+file^&sourceid=opera^&ie=utf-8^&oe=utf-8

How to subtract/add days from/to a date?

The answer probably depends on what format your date is in, but here is an example using the Date class:

dt <- as.Date("2010/02/10")
new.dt <- dt - as.difftime(2, unit="days")

You can even play with different units like weeks.

Print a variable in hexadecimal in Python

A way that will fail if your input string isn't valid pairs of hex characters...:

>>> import binascii
>>> ' '.join(hex(ord(i)) for i in binascii.unhexlify('deadbeef'))
'0xde 0xad 0xbe 0xef'

Where is the visual studio HTML Designer?

The solution of creating a new HTML file with HTML (Web Forms) Designer worked for that file but not for other, individual HTML files that I wanted to edit.

I did find the Open With option in the Open File dialogue and was able to select the HTML (Web Forms) Editor there. Having clicked the "Set as Default" option in that window, VS then remembered to use that editor when I opened other HTML files.

How to get summary statistics by group

While some of the other approaches work, this is pretty close to what you were doing and only uses base r. If you know the aggregate command this may be more intuitive.

with( df , aggregate( dt , by=list(group) , FUN=summary)  )

How to increase the Java stack size?

Add this option

--driver-java-options -Xss512m

to your spark-submit command will fix this issue.

What is the difference between MySQL, MySQLi and PDO?

There are (more than) three popular ways to use MySQL from PHP. This outlines some features/differences PHP: Choosing an API:

  1. (DEPRECATED) The mysql functions are procedural and use manual escaping.
  2. MySQLi is a replacement for the mysql functions, with object-oriented and procedural versions. It has support for prepared statements.
  3. PDO (PHP Data Objects) is a general database abstraction layer with support for MySQL among many other databases. It provides prepared statements, and significant flexibility in how data is returned.

I would recommend using PDO with prepared statements. It is a well-designed API and will let you more easily move to another database (including any that supports ODBC) if necessary.

Unable to install pyodbc on Linux

I have referenced this question several times, and gone on to actually find the answer I was looking for here: pyodbc wiki

To avoid gcc error on Ubuntu Linux, I did:

sudo aptitude install g++

I also installed the following 2 packages from Synaptic:

  • python-dev

  • tdsodbc

How to check if a String contains any letter from a to z?

Use regular expression no need to convert it to char array

if(Regex.IsMatch("yourString",".*?[a-zA-Z].*?"))
{
errorCounter++;
}

Laravel Rule Validation for Numbers

Laravel min and max validation do not work properly with a numeric rule validation. Instead of numeric, min and max, Laravel provided a rule digits_between.

$this->validate($request,[
        'field_name'=>'digits_between:2,5',
       ]);

How to declare a type as nullable in TypeScript?

Just add a question mark ? to the optional field.

interface Employee{
   id: number;
   name: string;
   salary?: number;
}

Creating and playing a sound in swift

For Swift 3:

extension SystemSoundID {
    static func playFileNamed(_ fileName: String, withExtenstion fileExtension: String) {
        var sound: SystemSoundID = 0
        if let soundURL = Bundle.main.url(forResource: fileName, withExtension: fileExtension) {
            AudioServicesCreateSystemSoundID(soundURL as CFURL, &sound)
            AudioServicesPlaySystemSound(sound)
        }
    }
}

Typescript: difference between String and string

TypeScript: String vs string

Argument of type 'String' is not assignable to parameter of type 'string'.

'string' is a primitive, but 'String' is a wrapper object.

Prefer using 'string' when possible.

demo

String Object

// error
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: String = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: String = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

string primitive

// ok
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: string = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: string = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

enter image description here

Purpose of Unions in C and C++

In C++, Boost Variant implement a safe version of the union, designed to prevent undefined behavior as much as possible.

Its performances are identical to the enum + union construct (stack allocated too etc) but it uses a template list of types instead of the enum :)

Where am I? - Get country

Use this link http://ip-api.com/json ,this will provide all the information as json. From this json you can get the country easily. This site works using your current IP,it automatically detects the IP and sendback details.

Docs http://ip-api.com/docs/api:json Hope it helps.

Example json

{
  "status": "success",
  "country": "United States",
  "countryCode": "US",
  "region": "CA",
  "regionName": "California",
  "city": "San Francisco",
  "zip": "94105",
  "lat": "37.7898",
  "lon": "-122.3942",
  "timezone": "America/Los_Angeles",
  "isp": "Wikimedia Foundation",
  "org": "Wikimedia Foundation",
  "as": "AS14907 Wikimedia US network",
  "query": "208.80.152.201"
}

note : As this is a 3rd party solution, only use if others didn't work.

if else in a list comprehension

One way:

def change(f):
    if f is None:
        return unicode(f.strip())
    else:
        return ''

row = [change(x) for x in row]

Although then you have:

row = map(change, row)

Or you can use a lambda inline.

Forbidden You don't have permission to access / on this server

Solution is just simple.

If you are trying to access server using your local IP address and you are getting error saying like Forbidden You don't have permission to access / on this server

Just open your httpd.conf file from (in my case C:/wamp/bin/apache/apache2.2.21/conf/httpd.conf)

Search for

<Directory "D:/wamp/www/"> .... ..... </Directory>

Replace Allow from 127.0.0.1

to

Allow from all

Save changes and restart your server.

Now you can access your server using your IP address

Why use HttpClient for Synchronous Connection

If you're building a class library, then perhaps the users of your library would like to use your library asynchronously. I think that's the biggest reason right there.

You also don't know how your library is going to be used. Perhaps the users will be processing lots and lots of requests, and doing so asynchronously will help it perform faster and more efficient.

If you can do so simply, try not to put the burden on the users of your library trying to make the flow asynchronous when you can take care of it for them.

The only reason I wouldn't use the async version is if I were trying to support an older version of .NET that does not already have built in async support.

How to get the pure text without HTML element using JavaScript?

[2017-07-25] since this continues to be the accepted answer, despite being a very hacky solution, I'm incorporating Gabi's code into it, leaving my own to serve as a bad example.

_x000D_
_x000D_
// my hacky approach:
function get_content() {
  var html = document.getElementById("txt").innerHTML;
  document.getElementById("txt").innerHTML = html.replace(/<[^>]*>/g, "");
}
// Gabi's elegant approach, but eliminating one unnecessary line of code:
function gabi_content() {
  var element = document.getElementById('txt');
  element.innerHTML = element.innerText || element.textContent;
}
// and exploiting the fact that IDs pollute the window namespace:
function txt_content() {
  txt.innerHTML = txt.innerText || txt.textContent;
}
_x000D_
.A {
  background: blue;
}

.B {
  font-style: italic;
}

.C {
  font-weight: bold;
}
_x000D_
<input type="button" onclick="get_content()" value="Get Content (bad)" />
<input type="button" onclick="gabi_content()" value="Get Content (good)" />
<input type="button" onclick="txt_content()" value="Get Content (shortest)" />
<p id='txt'>
  <span class="A">I am</span>
  <span class="B">working in </span>
  <span class="C">ABC company.</span>
</p>
_x000D_
_x000D_
_x000D_

validate natural input number with ngpattern

This is working

<form name="myform" ng-submit="create()">
    <input type="number"
           name="price_field"
           ng-model="price"
           require
           ng-pattern="/^\d{0,9}(\.\d{1,9})?$/">
    <span  ng-show="myform.price_field.$error.pattern">Not valid number!</span>
    <input type="submit" class="btn">
 </form>

How to show current user name in a cell?

The simplest way is to create a VBA macro that wraps that function, like so:

Function UserNameWindows() As String
    UserName = Environ("USERNAME")
End Function

Then call it from the cell:

=UserNameWindows()

See this article for more details, and other ways.

Bulk load data conversion error (type mismatch or invalid character for the specified codepage) for row 1, column 4 (Year)

The above options works for Google big query file also. I exported a table data to goodle cloud storage and downloaded from there. While loading the same to sql server was facing this issue and could successfully load the file after specifying the row delimiter as

ROWTERMINATOR = '0x0a' 

Pay attention to header record as well and specify

FIRSTROW = 2

My final block for data file export from google bigquery looks like this.

BULK INSERT TABLENAME
        FROM 'C:\ETL\Data\BigQuery\In\FILENAME.csv'
        WITH
        (
         FIRSTROW = 2,
         FIELDTERMINATOR = ',',  --CSV field delimiter
         ROWTERMINATOR = '0x0a',--Files are generated with this row terminator in Google Bigquery
         TABLOCK
        )

How to make a simple image upload using Javascript/HTML

Here's a simple example with no jQuery. Use URL.createObjectURL, which

creates a DOMString containing a URL representing the object given in the parameter

Then, you can simply set the src of the image to that url:

_x000D_
_x000D_
window.addEventListener('load', function() {
  document.querySelector('input[type="file"]').addEventListener('change', function() {
      if (this.files && this.files[0]) {
          var img = document.querySelector('img');
          img.onload = () => {
              URL.revokeObjectURL(img.src);  // no longer needed, free memory
          }

          img.src = URL.createObjectURL(this.files[0]); // set src to blob url
      }
  });
});
_x000D_
<input type='file' />
<br><img id="myImg" src="#">
_x000D_
_x000D_
_x000D_

How to use `subprocess` command with pipes

JKALAVIS solution is good, however I would add an improvement to use shlex instead of SHELL=TRUE. below im grepping out Query times

#!/bin/python
import subprocess
import shlex

cmd = "dig @8.8.4.4 +notcp www.google.com|grep 'Query'"
ps = subprocess.Popen(cmd,shell=True,stdout=subprocess.PIPE,stderr=subprocess.STDOUT)
output = ps.communicate()[0]
print(output)

Regex to get string between curly braces

/\{([^}]+)\}/

/        - delimiter
\{       - opening literal brace escaped because it is a special character used for quantifiers eg {2,3}
(        - start capturing
[^}]     - character class consisting of
    ^    - not
    }    - a closing brace (no escaping necessary because special characters in a character class are different)
+        - one or more of the character class
)        - end capturing
\}       - the closing literal brace
/        - delimiter

Generate insert script for selected records?

If possible use Visual Studio. The Microsoft SQL Server Data Tools (SSDT) bring a built in functionality for this since the March 2014 release:

  1. Open Visual Studio
  2. Open "View" ? "SQL Server Object Explorer"
  3. Add a connection to your Server
  4. Expand the relevant database
  5. Expand the "Tables" folder
  6. Right click on relevant table
  7. Select "View Data" from context menu
  8. In the new window, viewing the data use the "Sort and filter dataset" functionality in the tool bar to apply your filter. Note that this functionality is limited and you can't write explicit SQL queries.
  9. After you have applied your filter and see only the data you want, click on "Script" or "Script to file" in the tool bar
  10. Voilà - Here you have your insert script for your filtered data

Note: Be careful, the "View Data" window is just like SSMS "Edit Top 200 Rows"- you can edit data right away

(Tested with Visual Studio 2015 with Microsoft SQL Server Data Tools (SSDT) Version 14.0.60812.0 and Microsoft SQL Server 2012)

Is there a way to represent a directory tree in a Github README.md?

Insert command tree in bash.

Also, there is a DOS comnand "tree". You can displays directory paths and files in each subdirectory with command:

tree /F

https://web.csulb.edu/~murdock/tree.html

what is the multicast doing on 224.0.0.251?

If you don't have avahi installed then it's probably cups.

How to float a div over Google Maps?

absolute positioning is evil... this solution doesn't take into account window size. If you resize the browser window, your div will be out of place!

Grant SELECT on multiple tables oracle

This worked for me on my Oracle database:

SELECT   'GRANT SELECT, insert, update, delete ON mySchema.' || TABLE_NAME || ' to myUser;'
FROM     user_tables
where table_name like 'myTblPrefix%'

Then, copy the results, paste them into your editor, then run them like a script.

You could also write a script and use "Execute Immediate" to run the generated SQL if you don't want the extra copy/paste steps.

How can I create a blank/hardcoded column in a sql query?

For varchars, you may need to do something like this:

select convert(varchar(25), NULL) as abc_column into xyz_table

If you try

select '' as abc_column into xyz_table

you may get errors related to truncation, or an issue with null values, once you populate.

HTML Canvas Full Screen

Because it was not posted yet and is a simple css fix:

#canvas {
    position:fixed;
    left:0;
    top:0;
    width:100%;
    height:100%;
}

Works great if you want to apply a fullscreen canvas background (for example with Granim.js).

Change text color with Javascript?

Try below code:

$(document).ready(function(){
$('#about').css({'background-color':'black'});    
});

http://jsfiddle.net/jPCFC/

forEach() in React JSX does not output any HTML

You need to pass an array of element to jsx. The problem is that forEach does not return anything (i.e it returns undefined). So it's better to use map because map returns an array:

class QuestionSet extends Component {
render(){ 
    <div className="container">
       <h1>{this.props.question.text}</h1>
       {this.props.question.answers.map((answer, i) => {     
           console.log("Entered");                 
           // Return the element. Also pass key     
           return (<Answer key={answer} answer={answer} />) 
        })}
}

export default QuestionSet;

How to create a numpy array of all True or all False?

numpy already allows the creation of arrays of all ones or all zeros very easily:

e.g. numpy.ones((2, 2)) or numpy.zeros((2, 2))

Since True and False are represented in Python as 1 and 0, respectively, we have only to specify this array should be boolean using the optional dtype parameter and we are done.

numpy.ones((2, 2), dtype=bool)

returns:

array([[ True,  True],
       [ True,  True]], dtype=bool)

UPDATE: 30 October 2013

Since numpy version 1.8, we can use full to achieve the same result with syntax that more clearly shows our intent (as fmonegaglia points out):

numpy.full((2, 2), True, dtype=bool)

UPDATE: 16 January 2017

Since at least numpy version 1.12, full automatically casts results to the dtype of the second parameter, so we can just write:

numpy.full((2, 2), True)

How to use pip on windows behind an authenticating proxy

Try to encode backslash between domain and user

pip --proxy https://domain%5Cuser:password@proxy:port install -r requirements.txt

Escape @ character in razor view engine

I just had the same problem. I declared a variable putting my text with the @.

@{
   var twitterSite = "@MyTwitterSite";
}

...

<meta name="twitter:site" content="@twitterSite">

How to convert an NSString into an NSNumber

I know this is very late but below code is working for me.

Try this code

NSNumber *number = @([dictionary[@"keyValue"] intValue]]);

This may help you. Thanks

Bloomberg Open API

This API has been available for a long time and enables to get access to market data (including live) if you are running a Bloomberg Terminal or have access to a Bloomberg Server, which is chargeable.

The only difference is that the API (not its code) has been open sourced, so it can now be used as a dependency in an open source project for example, without any copyrights issues, which was not the case before.

gcc error: wrong ELF class: ELFCLASS64

You can specify '-m32' or '-m64' to select the compilation mode.

When dealing with autoconf (configure) scripts, I usually set CC="gcc -m64" (or CC="gcc -m32") in the environment so that everything is compiled with the correct bittiness. At least, usually...people find endless ways to make that not quite work, but my batting average is very high (way over 95%) with it.

Barcode scanner for mobile phone for Website in form

You can use the Android app Barcode Scanner Terminal (DISCLAIMER! I'm the developer). It can scan the barcode and send it to the PC and in your case enter it on the web form. More details here.

How to horizontally align ul to center of div?

Following is a list of solutions to centering things in CSS horizontally. The snippet includes all of them.

_x000D_
_x000D_
html {_x000D_
  font: 1.25em/1.5 Georgia, Times, serif;_x000D_
}_x000D_
_x000D_
pre {_x000D_
  color: #fff;_x000D_
  background-color: #333;_x000D_
  padding: 10px;_x000D_
}_x000D_
_x000D_
blockquote {_x000D_
  max-width: 400px;_x000D_
  background-color: #e0f0d1;_x000D_
}_x000D_
_x000D_
blockquote > p {_x000D_
  font-style: italic;_x000D_
}_x000D_
_x000D_
blockquote > p:first-of-type::before {_x000D_
  content: open-quote;_x000D_
}_x000D_
_x000D_
blockquote > p:last-of-type::after {_x000D_
  content: close-quote;_x000D_
}_x000D_
_x000D_
blockquote > footer::before {_x000D_
  content: "\2014";_x000D_
}_x000D_
_x000D_
.container,_x000D_
blockquote {_x000D_
  position: relative;_x000D_
  padding: 20px;_x000D_
}_x000D_
_x000D_
.container {_x000D_
  background-color: tomato;_x000D_
}_x000D_
_x000D_
.container::after,_x000D_
blockquote::after {_x000D_
  position: absolute;_x000D_
  right: 0;_x000D_
  bottom: 0;_x000D_
  padding: 2px 10px;_x000D_
  border: 1px dotted #000;_x000D_
  background-color: #fff;_x000D_
}_x000D_
_x000D_
.container::after {_x000D_
  content: ".container-" attr(data-num);_x000D_
  z-index: 1;_x000D_
}_x000D_
_x000D_
blockquote::after {_x000D_
  content: ".quote-" attr(data-num);_x000D_
  z-index: 2;_x000D_
}_x000D_
_x000D_
.container-4 {_x000D_
  margin-bottom: 200px;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Solution 1_x000D_
 */_x000D_
.quote-1 {_x000D_
  max-width: 400px;_x000D_
  margin-right: auto;_x000D_
  margin-left: auto;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Solution 2_x000D_
 */_x000D_
.container-2 {_x000D_
  text-align: center;_x000D_
}_x000D_
_x000D_
.quote-2 {_x000D_
  display: inline-block;_x000D_
  text-align: left;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Solution 3_x000D_
 */_x000D_
.quote-3 {_x000D_
  display: table;_x000D_
  margin-right: auto;_x000D_
  margin-left: auto;_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Solution 4_x000D_
 */_x000D_
.container-4 {_x000D_
  position: relative;_x000D_
}_x000D_
_x000D_
.quote-4 {_x000D_
  position: absolute;_x000D_
  left: 50%;_x000D_
  transform: translateX(-50%);_x000D_
}_x000D_
_x000D_
/**_x000D_
 * Solution 5_x000D_
 */_x000D_
.container-5 {_x000D_
  display: flex;_x000D_
  justify-content: center;_x000D_
}
_x000D_
<main>_x000D_
  <h1>CSS: Horizontal Centering</h1>_x000D_
_x000D_
  <h2>Uncentered Example</h2>_x000D_
  <p>This is the scenario: We have a container with an element inside of it that we want to center. I just added a little padding and background colors so both elements are distinquishable.</p>_x000D_
_x000D_
  <div class="container  container-0" data-num="0">_x000D_
    <blockquote class="quote-0" data-num="0">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
_x000D_
  <h2>Solution 1: Using <code>max-width</code> & <code>margin</code> (IE7)</h2>_x000D_
_x000D_
  <p>This method is widely used. The upside here is that only the element which one wants to center needs rules.</p>_x000D_
_x000D_
<pre><code>.quote-1 {_x000D_
  max-width: 400px;_x000D_
  margin-right: auto;_x000D_
  margin-left: auto;_x000D_
}</code></pre>_x000D_
_x000D_
  <div class="container  container-1" data-num="1">_x000D_
    <blockquote class="quote  quote-1" data-num="1">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
_x000D_
  <h2>Solution 2: Using <code>display: inline-block</code> and <code>text-align</code> (IE8)</h2>_x000D_
_x000D_
  <p>This method utilizes that <code>inline-block</code> elements are treated as text and as such they are affected by the <code>text-align</code> property. This does not rely on a fixed width which is an upside. This is helpful for when you don’t know the number of elements in a container for example.</p>_x000D_
_x000D_
<pre><code>.container-2 {_x000D_
  text-align: center;_x000D_
}_x000D_
_x000D_
.quote-2 {_x000D_
  display: inline-block;_x000D_
  text-align: left;_x000D_
}</code></pre>_x000D_
_x000D_
  <div class="container  container-2" data-num="2">_x000D_
    <blockquote class="quote  quote-2" data-num="2">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
_x000D_
  <h2>Solution 3: Using <code>display: table</code> and <code>margin</code> (IE8)</h2>_x000D_
_x000D_
  <p>Very similar to the second solution but only requires to apply rules on the element that is to be centered.</p>_x000D_
_x000D_
<pre><code>.quote-3 {_x000D_
  display: table;_x000D_
  margin-right: auto;_x000D_
  margin-left: auto;_x000D_
}</code></pre>_x000D_
_x000D_
  <div class="container  container-3" data-num="3">_x000D_
    <blockquote class="quote  quote-3" data-num="3">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
_x000D_
  <h2>Solution 4: Using <code>translate()</code> and <code>position</code> (IE9)</h2>_x000D_
_x000D_
  <p>Don’t use as a general approach for horizontal centering elements. The downside here is that the centered element will be removed from the document flow. Notice the container shrinking to zero height with only the padding keeping it visible. This is what <i>removing an element from the document flow</i> means.</p>_x000D_
_x000D_
  <p>There are however applications for this technique. For example, it works for <b>vertically</b> centering by using <code>top</code> or <code>bottom</code> together with <code>translateY()</code>.</p>_x000D_
_x000D_
<pre><code>.container-4 {_x000D_
    position: relative;_x000D_
}_x000D_
_x000D_
.quote-4 {_x000D_
  position: absolute;_x000D_
  left: 50%;_x000D_
  transform: translateX(-50%);_x000D_
}</code></pre>_x000D_
_x000D_
  <div class="container  container-4" data-num="4">_x000D_
    <blockquote class="quote  quote-4" data-num="4">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
_x000D_
  <h2>Solution 5: Using Flexible Box Layout Module (IE10+ with vendor prefix)</h2>_x000D_
_x000D_
  <p></p>_x000D_
_x000D_
<pre><code>.container-5 {_x000D_
  display: flex;_x000D_
  justify-content: center;_x000D_
}</code></pre>_x000D_
_x000D_
  <div class="container  container-5" data-num="5">_x000D_
    <blockquote class="quote  quote-5" data-num="5">_x000D_
      <p>My friend Data. You see things with the wonder of a child. And that makes you more human than any of us.</p>_x000D_
      <footer>Tasha Yar about Data</footer>_x000D_
    </blockquote>_x000D_
  </div>_x000D_
</main>
_x000D_
_x000D_
_x000D_


display: flex

.container {
  display: flex;
  justify-content: center;
}

Notes:


max-width & margin

You can horizontally center a block-level element by assigning a fixed width and setting margin-right and margin-left to auto.

.container ul {
  /* for IE below version 7 use `width` instead of `max-width` */
  max-width: 800px;
  margin-right: auto;
  margin-left: auto;
}

Notes:

  • No container needed
  • Requires (maximum) width of the centered element to be known

IE9+: transform: translatex(-50%) & left: 50%

This is similar to the quirky centering method which uses absolute positioning and negative margins.

.container {
  position: relative;
}

.container ul {
  position: absolute;
  left: 50%;
  transform: translatex(-50%);
}

Notes:

  • The centered element will be removed from document flow. All elements will completely ignore of the centered element.
  • This technique allows vertical centering by using top instead of left and translateY() instead of translateX(). The two can even be combined.
  • Browser support: transform2d

IE8+: display: table & margin

Just like the first solution, you use auto values for right and left margins, but don’t assign a width. If you don’t need to support IE7 and below, this is better suited, although it feels kind of hacky to use the table property value for display.

.container ul {
  display: table;
  margin-right: auto;
  margin-left: auto;
}

IE8+: display: inline-block & text-align

Centering an element just like you would do with regular text is possible as well. Downside: You need to assign values to both a container and the element itself.

.container {
  text-align: center;
}

.container ul {
  display: inline-block;

  /* One most likely needs to realign flow content */
  text-align: initial;
}

Notes:

  • Does not require to specify a (maximum) width
  • Aligns flow content to the center (potentially unwanted side effect)
  • Works kind of well with a dynamic number of menu items (i.e. in cases where you can’t know the width a single item will take up)

How can I get an int from stdio in C?

I'm not fully sure that this is what you're looking for, but if your question is how to read an integer using <stdio.h>, then the proper syntax is

int myInt;
scanf("%d", &myInt);

You'll need to do a lot of error-handling to ensure that this works correctly, of course, but this should be a good start. In particular, you'll need to handle the cases where

  1. The stdin file is closed or broken, so you get nothing at all.
  2. The user enters something invalid.

To check for this, you can capture the return code from scanf like this:

int result = scanf("%d", &myInt);

If stdin encounters an error while reading, result will be EOF, and you can check for errors like this:

int myInt;
int result = scanf("%d", &myInt);

if (result == EOF) {
    /* ... you're not going to get any input ... */
}

If, on the other hand, the user enters something invalid, like a garbage text string, then you need to read characters out of stdin until you consume all the offending input. You can do this as follows, using the fact that scanf returns 0 if nothing was read:

int myInt;
int result = scanf("%d", &myInt);

if (result == EOF) {
    /* ... you're not going to get any input ... */
}
if (result == 0) {
    while (fgetc(stdin) != '\n') // Read until a newline is found
        ;
}

Hope this helps!

EDIT: In response to the more detailed question, here's a more appropriate answer. :-)

The problem with this code is that when you write

printf("got the number: %d", scanf("%d", &x));

This is printing the return code from scanf, which is EOF on a stream error, 0 if nothing was read, and 1 otherwise. This means that, in particular, if you enter an integer, this will always print 1 because you're printing the status code from scanf, not the number you read.

To fix this, change this to

int x;
scanf("%d", &x);
/* ... error checking as above ... */
printf("got the number: %d", x);

Hope this helps!

Creating a JSON response using Django and Python

Use JsonResponse

from django.http import JsonResponse

Conversion failed when converting the varchar value 'simple, ' to data type int

In order to avoid such error you could use CASE + ISNUMERIC to handle scenarios when you cannot convert to int.
Change

CONVERT(INT, CONVERT(VARCHAR(12), a.value))

To

CONVERT(INT,
        CASE
        WHEN IsNumeric(CONVERT(VARCHAR(12), a.value)) = 1 THEN CONVERT(VARCHAR(12),a.value)
        ELSE 0 END) 

Basically this is saying if you cannot convert me to int assign value of 0 (in my example)

Alternatively you can look at this article about creating a custom function that will check if a.value is number: http://www.tek-tips.com/faqs.cfm?fid=6423

Send email using the GMail SMTP server from a PHP page

I had this problem also. I set the correct settings and have enabled less secure apps but it still did not work. Finally, I enabled this https://accounts.google.com/UnlockCaptcha, and it worked for me. I hope this helps someone.

RegEx to match stuff between parentheses

var getMatchingGroups = function(s) {
  var r=/\((.*?)\)/g, a=[], m;
  while (m = r.exec(s)) {
    a.push(m[1]);
  }
  return a;
};

getMatchingGroups("something/([0-9])/([a-z])"); // => ["[0-9]", "[a-z]"]

How can I rename a single column in a table at select?

select table1.price, table2.price as other_price .....

Spring data jpa- No bean named 'entityManagerFactory' is defined; Injection of autowired dependencies failed

I think this is related to the newer version of spring boot plus using spring data JPA just replace @Bean annotation above public LocalContainerEntityManagerFactoryBean entityManagerFactory() to @Bean(name="entityManagerFactory")

Determining the name of bean should solve the issue

Why am I getting a " Traceback (most recent call last):" error?

I don't know which version of Python you are using but I tried this in Python 3 and made a few changes and it looks like it works. The raw_input function seems to be the issue here. I changed all the raw_input functions to "input()" and I also made minor changes to the printing to be compatible with Python 3. AJ Uppal is correct when he says that you shouldn't name a variable and a function with the same name. See here for reference:

TypeError: 'int' object is not callable

My code for Python 3 is as follows:

# https://stackoverflow.com/questions/27097039/why-am-i-getting-a-traceback-most-recent-call-last-error

raw_input = 0
M = 1.6
# Miles to Kilometers
# Celsius Celsius = (var1 - 32) * 5/9
# Gallons to liters Gallons = 3.6
# Pounds to kilograms Pounds = 0.45
# Inches to centimete Inches = 2.54


def intro():
    print("Welcome! This program will convert measures for you.")
    main()

def main():
    print("Select operation.")
    print("1.Miles to Kilometers")
    print("2.Fahrenheit to Celsius")
    print("3.Gallons to liters")
    print("4.Pounds to kilograms")
    print("5.Inches to centimeters")

    choice = input("Enter your choice by number: ")

    if choice == '1':
        convertMK()

    elif choice == '2':
        converCF()

    elif choice == '3':
        convertGL()

    elif choice == '4':
        convertPK()

    elif choice == '5':
        convertPK()

    else:
        print("Error")


def convertMK():
    input_M = float(input(("Miles: ")))
    M_conv = (M) * input_M
    print("Kilometers: {M_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print("I didn't quite understand that answer. Terminating.")
        main()

def converCF():
    input_F = float(input(("Fahrenheit: ")))
    F_conv = (input_F - 32) * 5/9
    print("Celcius: {F_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print("I didn't quite understand that answer. Terminating.")
        main()

def convertGL():
    input_G = float(input(("Gallons: ")))
    G_conv = input_G * 3.6
    print("Centimeters: {G_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print ("I didn't quite understand that answer. Terminating.")
        main()

def convertPK():
    input_P = float(input(("Pounds: ")))
    P_conv = input_P * 0.45
    print("Centimeters: {P_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print ("I didn't quite understand that answer. Terminating.")
        main()

def convertIC():
    input_cm = float(input(("Inches: ")))
    inches_conv = input_cm * 2.54
    print("Centimeters: {inches_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print ("I didn't quite understand that answer. Terminating.")
        main()

def end():
    print("This program will close.")
    exit()

intro()

I noticed a small bug in your code as well. This function should ideally convert pounds to kilograms but it looks like when it prints, it is printing "Centimeters" instead of kilograms.

def convertPK():
    input_P = float(input(("Pounds: ")))
    P_conv = input_P * 0.45
    # Printing error in the line below
    print("Centimeters: {P_conv}\n")
    restart = str(input("Do you wish to make another conversion? [y]Yes or [n]no: "))
    if restart == 'y':
        main()
    elif restart == 'n':
        end()
    else:
        print ("I didn't quite understand that answer. Terminating.")
        main()

I hope this helps.

Eventviewer eventid for lock and unlock

Unfortunately there is no such a thing as Lock/Unlock. What you have to do is:

  1. Click on "Filter Current Log..."
  2. Select the XML tab and click on "Edit query manually"
  3. Enter the below query:

    <QueryList>
      <Query Id="0" Path="Security">
        <Select Path="Security">
        *[EventData[Data[@Name='LogonType']='7']
         and
         (System[(EventID='4634')] or System[(EventID='4624')])
         ]</Select>
      </Query>
    </QueryList>
    

That's it

How to Generate Barcode using PHP and Display it as an Image on the same page

There is a library for this BarCode PHP. You just need to include a few files:

require_once('class/BCGFontFile.php');
require_once('class/BCGColor.php');
require_once('class/BCGDrawing.php');

You can generate many types of barcodes, namely 1D or 2D. Add the required library:

require_once('class/BCGcode39.barcode.php');

Generate the colours:

// The arguments are R, G, and B for color.
$colorFront = new BCGColor(0, 0, 0);
$colorBack = new BCGColor(255, 255, 255);

After you have added all the codes, you will get this way:

Example

Since several have asked for an example here is what I was able to do to get it done

require_once('class/BCGFontFile.php');
require_once('class/BCGColor.php');
require_once('class/BCGDrawing.php');

require_once('class/BCGcode128.barcode.php');

header('Content-Type: image/png');

$color_white = new BCGColor(255, 255, 255);

$code = new BCGcode128();
$code->parse('HELLO');

$drawing = new BCGDrawing('', $color_white);
$drawing->setBarcode($code);

$drawing->draw();
$drawing->finish(BCGDrawing::IMG_FORMAT_PNG);

If you want to actually create the image file so you can save it then change

$drawing = new BCGDrawing('', $color_white);

to

$drawing = new BCGDrawing('image.png', $color_white);

Flask SQLAlchemy query, specify column names

You can use Query.values, Query.values

session.query(SomeModel).values('id', 'user')

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

  1. The accepted answer is one way of fixing the issue, because it will just apply some strategy for the problematic dependency (com.google.code.findbugs:jsr305) and it will resolve the problem around the project, using some version of this dependency. Basically it will align the versions of this library inside the whole project.

  2. There is an answer from @Santhosh (and couple of other people) who suggests to exclude the same dependency for espresso, which should work by the same way, but if the project has some other dependencies who depend on the same library (com.google.code.findbugs:jsr305), again we will have the same issue. So in order to use this approach you will need to exclude the same group from all project dependencies, who depend on com.google.code.findbugs:jsr305. I personally found that Espresso Contrib and Espresso Intents also use com.google.code.findbugs:jsr305.

I hope this thoughts will help somebody to realise what exactly is happening here and how things work (not just copy paste some code) :).

postgresql duplicate key violates unique constraint

The primary key is already protecting you from inserting duplicate values, as you're experiencing when you get that error. Adding another unique constraint isn't necessary to do that.

The "duplicate key" error is telling you that the work was not done because it would produce a duplicate key, not that it discovered a duplicate key already commited to the table.

Detect if PHP session exists

Which method is used to check if SESSION exists or not? Answer:

isset($_SESSION['variable_name'])

Example:

isset($_SESSION['id'])

maven error: package org.junit does not exist

I fixed this error by inserting these lines of code:

<dependency>
  <groupId>junit</groupId>     <!-- NOT org.junit here -->
  <artifactId>junit-dep</artifactId>
  <version>4.8.2</version>
  <scope>test</scope>
</dependency>

into <dependencies> node.

more details refer to: http://mvnrepository.com/artifact/junit/junit-dep/4.8.2

How to access Winform textbox control from another class?

You can change the access modifier for the generated field in Form1.Designer.cs from private to public. Change this

private System.Windows.Forms.TextBox textBox1;

by this

public System.Windows.Forms.TextBox textBox1;

You can now handle it using a reference of the form Form1.textBox1.

Visual Studio will not overwrite this if you make any changes to the control properties, unless you delete it and recreate it.

You can also chane it from the UI if you are not confortable with editing code directly. Look for the Modifiers property:

Modifiers

Location of the android sdk has not been setup in the preferences in mac os?

I've had the same problem on Eclipse Juno.

No "Welcome page" appeared, I could not create a project, compilation didn't work and "Graphical layout" didn't work.

I have fixed it: Window > Preferences > General > Startup and shutdown: Check "Android development toolkit"

Reestart Eclipse.

Of course you have to be configured this: Window - Preferences - Android - SDK Location and setup SDK path.

Basic calculator in Java

Remove the semi-colons from your if statements, otherwise the code that follows will be free standing and will always execute:

if (operation == "+");
                     ^

Also use .equals for Strings, == compares Object references:

 if (operation.equals("+")) {

how does multiplication differ for NumPy Matrix vs Array classes?

Reference from http://docs.scipy.org/doc/scipy/reference/tutorial/linalg.html

..., the use of the numpy.matrix class is discouraged, since it adds nothing that cannot be accomplished with 2D numpy.ndarray objects, and may lead to a confusion of which class is being used. For example,

>>> import numpy as np
>>> from scipy import linalg
>>> A = np.array([[1,2],[3,4]])
>>> A
    array([[1, 2],
           [3, 4]])
>>> linalg.inv(A)
array([[-2. ,  1. ],
      [ 1.5, -0.5]])
>>> b = np.array([[5,6]]) #2D array
>>> b
array([[5, 6]])
>>> b.T
array([[5],
      [6]])
>>> A*b #not matrix multiplication!
array([[ 5, 12],
      [15, 24]])
>>> A.dot(b.T) #matrix multiplication
array([[17],
      [39]])
>>> b = np.array([5,6]) #1D array
>>> b
array([5, 6])
>>> b.T  #not matrix transpose!
array([5, 6])
>>> A.dot(b)  #does not matter for multiplication
array([17, 39])

scipy.linalg operations can be applied equally to numpy.matrix or to 2D numpy.ndarray objects.

Check if datetime instance falls in between other two datetime objects

Write yourself a Helper function:

public static bool IsBewteenTwoDates(this DateTime dt, DateTime start, DateTime end)
{
    return dt >= start && dt <= end;
}

Then call: .IsBewteenTwoDates(DateTime.Today ,new DateTime(,,));

Background color of text in SVG

The previous answers relied on doubling up text and lacked sufficient whitespace.

By using atop and &nbsp; I was able to get the results I wanted.

This example also includes arrows, a common use case for SVG text labels:

<svg viewBox="-105 -40 210 234">
<title>Size Guide</title>
<defs>
    <filter x="0" y="0" width="1" height="1" id="solid">
        <feFlood flood-color="white"></feFlood>
        <feComposite in="SourceGraphic" operator="atop"></feComposite>
    </filter>
    <marker id="arrow" viewBox="0 0 10 10" refX="5" refY="5" markerWidth="6" markerHeight="6" orient="auto-start-reverse">
        <path d="M 0 0 L 10 5 L 0 10 z"></path>
    </marker>
</defs>
<g id="garment">
    <path id="right-body" fill="none" stroke="black" stroke-width="1" stroke-linejoin="round" d="M0 0 l30 0 l0 154 l-30 0"></path>
    <path id="right-sleeve" d="M30 0 l35 0 l0 120 l-35 0" fill="none" stroke-linejoin="round" stroke="black" stroke-width="1"></path>
    <use id="left-body" href="#right-body" transform="scale(-1,1)"></use>
    <use id="left-sleeve" href="#right-sleeve" transform="scale(-1,1)"></use>
    <path id="collar-right-top" fill="none" stroke="black" stroke-width="1" stroke-linejoin="round" d="M0 -6.5 l11.75 0 l6.5 6.5"></path>
    <use id="collar-left-top" href="#collar-right-top" transform="scale(-1,1)"></use>
    <path id="collar-left" fill="white" stroke="black" stroke-width="1" stroke-linejoin="round" d="M-11.75 -6.5 l-6.5 6.5 l30 77 l6.5 -6.5 Z"></path>
    <path id="front-right" fill="white" stroke="black" stroke-width="1" d="M18.25 0 L30 0 l0 154 l-41.75 0 l0 -77 Z"></path>
    <line x1="0" y1="0" x2="0" y2="154" stroke="black" stroke-width="1" stroke-dasharray="1 3"></line>
    <use id="collar-right" href="#collar-left" transform="scale(-1,1)"></use>
</g>
<g id="dimension-labels">
    <g id="dimension-sleeve-length">
        <line marker-start="url(#arrow)" marker-end="url(#arrow)" x1="85" y1="0" x2="85" y2="120" stroke="black" stroke-width="1"></line>
        <text font-size="10" filter="url(#solid)" fill="black" x="85" y="60" class="dimension" text-anchor="middle" dominant-baseline="middle"> 120 cm</text>
    </g>
    <g id="dimension-length">
        <line marker-start="url(#arrow)" marker-end="url(#arrow)" x1="-85" y1="0" x2="-85" y2="154" stroke="black" stroke-width="1"></line>
        <text font-size="10" filter="url(#solid)" fill="black" x="-85" y="77" text-anchor="middle" dominant-baseline="middle" class="dimension"> 154 cm</text>
    </g>
    <g id="dimension-sleeve-to-sleeve">
        <line marker-start="url(#arrow)" marker-end="url(#arrow)" x1="-65" y1="-20" x2="65" y2="-20" stroke="black" stroke-width="1"></line>
        <text font-size="10" filter="url(#solid)" fill="black" x="0" y="-20" text-anchor="middle" dominant-baseline="middle" class="dimension">&nbsp;130 cm&nbsp;</text>
    </g>
    <g title="Back Width" id="dimension-back-width">
        <line marker-start="url(#arrow)" marker-end="url(#arrow)" x1="-30" y1="174" x2="30" y2="174" stroke="black" stroke-width="1"></line>
        <text font-size="10" filter="url(#solid)" fill="black" x="0" y="174" text-anchor="middle" dominant-baseline="middle" class="dimension">&nbsp;60 cm&nbsp;</text>
    </g>
</g>
</svg>

Find out a Git branch creator

I tweaked the previous answers by using the --sort flag and added some color/formatting:

git for-each-ref --format='%(color:cyan)%(authordate:format:%m/%d/%Y %I:%M %p)    %(align:25,left)%(color:yellow)%(authorname)%(end) %(color:reset)%(refname:strip=3)' --sort=authordate refs/remotes

How can I enable or disable the GPS programmatically on Android?

Instead of using intent Settings.ACTION_LOCATION_SOURCE_SETTINGS you can directly able to show pop up in your app like Google Map & on Gps on click of ok button their is no need to redirect to setting simply you need to use my code as

Note : This line of code automatic open the dialog box if Location is not on. This piece of line is used in Google Map also

 public class MainActivity extends AppCompatActivity
    implements GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener {


LocationRequest mLocationRequest;
GoogleApiClient mGoogleApiClient;
PendingResult<LocationSettingsResult> result;
final static int REQUEST_LOCATION = 199;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    mGoogleApiClient = new GoogleApiClient.Builder(this)
            .addApi(LocationServices.API)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this).build();
    mGoogleApiClient.connect();

}

@Override
public void onConnected(Bundle bundle) {

    mLocationRequest = LocationRequest.create();
    mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
    mLocationRequest.setInterval(30 * 1000);
    mLocationRequest.setFastestInterval(5 * 1000);

    LocationSettingsRequest.Builder builder = new LocationSettingsRequest.Builder()
            .addLocationRequest(mLocationRequest);
    builder.setAlwaysShow(true);

    result = LocationServices.SettingsApi.checkLocationSettings(mGoogleApiClient, builder.build());

    result.setResultCallback(new ResultCallback<LocationSettingsResult>() {
        @Override
        public void onResult(LocationSettingsResult result) {
            final Status status = result.getStatus();
            //final LocationSettingsStates state = result.getLocationSettingsStates();
            switch (status.getStatusCode()) {
                case LocationSettingsStatusCodes.SUCCESS:
                    // All location settings are satisfied. The client can initialize location
                    // requests here.
                    //...
                    break;
                case LocationSettingsStatusCodes.RESOLUTION_REQUIRED:
                    // Location settings are not satisfied. But could be fixed by showing the user
                    // a dialog.
                    try {
                        // Show the dialog by calling startResolutionForResult(),
                        // and check the result in onActivityResult().
                        status.startResolutionForResult(
                                MainActivity.this,
                                REQUEST_LOCATION);
                    } catch (SendIntentException e) {
                        // Ignore the error.
                    }
                    break;
                case LocationSettingsStatusCodes.SETTINGS_CHANGE_UNAVAILABLE:
                    // Location settings are not satisfied. However, we have no way to fix the
                    // settings so we won't show the dialog.
                    //...
                    break;
            }
        }
    });

}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data)
{
    Log.d("onActivityResult()", Integer.toString(resultCode));

    //final LocationSettingsStates states = LocationSettingsStates.fromIntent(data);
    switch (requestCode)
    {
        case REQUEST_LOCATION:
            switch (resultCode)
            {
                case Activity.RESULT_OK:
                {
                    // All required changes were successfully made
                    Toast.makeText(MainActivity.this, "Location enabled by user!", Toast.LENGTH_LONG).show();
                    break;
                }
                case Activity.RESULT_CANCELED:
                {
                    // The user was asked to change settings, but chose not to
                    Toast.makeText(MainActivity.this, "Location not enabled, user cancelled.", Toast.LENGTH_LONG).show();
                    break;
                }
                default:
                {
                    break;
                }
            }
            break;
    }
}

@Override
public void onConnectionSuspended(int i) {

}

@Override
public void onConnectionFailed(ConnectionResult connectionResult) {

}
} 

Note : This line of code automatic open the dialog box if Location is not on. This piece of line is used in Google Map also

How to convert Set to Array?

The code below creates a set from an array and then, using the ... operator.

var arr=[1,2,3,4,5,6,7,8,9,1,2,3,4,5,6,7,8,9,];
var set=new Set(arr);
let setarr=[...set];
console.log(setarr);

Remove Backslashes from Json Data in JavaScript

Your string is invalid, but assuming it was valid, you'd have to do:

var finalData = str.replace(/\\/g, "");

When you want to replace all the occurences with .replace, the first parameter must be a regex, if you supply a string, only the first occurrence will be replaced, that's why your replace wouldn't work.

Cheers

Number of times a particular character appears in a string

There's no direct function for this, but you can do it with a replace:

declare @myvar varchar(20)
set @myvar = 'Hello World'

select len(@myvar) - len(replace(@myvar,'o',''))

Basically this tells you how many chars were removed, and therefore how many instances of it there were.

Extra:

The above can be extended to count the occurences of a multi-char string by dividing by the length of the string being searched for. For example:

declare @myvar varchar(max), @tocount varchar(20)
set @myvar = 'Hello World, Hello World'
set @tocount = 'lo'

select (len(@myvar) - len(replace(@myvar,@tocount,''))) / LEN(@tocount)

Remove all files except some from a directory

Make the files immutable. Not even root will be allowed to delete them.

chattr +i textfile.txt backup.tar.gz script.php database.sql info.txt
rm *

All other files have been deleted.
Eventually you can reset them mutable.

chattr -i *

How can you strip non-ASCII characters from a string? (in C#)

If you want not to strip, but to actually convert latin accented to non-accented characters, take a look at this question: How do I translate 8bit characters into 7bit characters? (i.e. Ü to U)

How do I give text or an image a transparent background using CSS?

Here is a jQuery plugin that will handle everything for you, Transify (Transify - a jQuery plugin to easily apply transparency / opacity to an element’s background).

I was running into this problem every now and then, so I decided to write something that would make life a lot easier. The script is less than 2 KB and it only requires one line of code to get it to work, and it will also handle animating the opacity of the background if you like.

How to find out which JavaScript events fired?

Regarding Chrome, checkout the monitorEvents() via the command line API.

  • Open the console via Menu > Tools > JavaScript Console.

  • Enter monitorEvents(window);

  • View the console flooded with events

     ...
     mousemove MouseEvent {dataTransfer: ...}
     mouseout MouseEvent {dataTransfer: ...}
     mouseover MouseEvent {dataTransfer: ...}
     change Event {clipboardData: ...}
     ...
    

There are other examples in the documentation. I'm guessing this feature was added after the previous answer.

What does "publicPath" in Webpack do?

the publicPath is just used for dev purpose, I was confused at first time I saw this config property, but it makes sense now that I've used webpack for a while

suppose you put all your js source file under src folder, and you config your webpack to build the source file to dist folder with output.path.

But you want to serve your static assets under a more meaningful location like webroot/public/assets, this time you can use out.publicPath='/webroot/public/assets', so that in your html, you can reference your js with <script src="/webroot/public/assets/bundle.js"></script>.

when you request webroot/public/assets/bundle.js the webpack-dev-server will find the js under the dist folder

Update:

thanks for Charlie Martin to correct my answer

original: the publicPath is just used for dev purpose, this is not just for dev purpose

No, this option is useful in the dev server, but its intention is for asynchronously loading script bundles in production. Say you have a very large single page application (for example Facebook). Facebook wouldn't want to serve all of its javascript every time you load the homepage, so it serves only whats needed on the homepage. Then, when you go to your profile, it loads some more javascript for that page with ajax. This option tells it where on your server to load that bundle from

iOS start Background Thread

Swift 2.x answer:

    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0)) {
        self.getResultSetFromDB(docids)
    }

Principal Component Analysis (PCA) in Python

You can find a PCA function in the matplotlib module:

import numpy as np
from matplotlib.mlab import PCA

data = np.array(np.random.randint(10,size=(10,3)))
results = PCA(data)

results will store the various parameters of the PCA. It is from the mlab part of matplotlib, which is the compatibility layer with the MATLAB syntax

EDIT: on the blog nextgenetics I found a wonderful demonstration of how to perform and display a PCA with the matplotlib mlab module, have fun and check that blog!

ggplot2: sorting a plot

I've recently been struggling with a related issue, discussed at length here: Order of legend entries in ggplot2 barplots with coord_flip() .

As it happens, the reason I had a hard time explaining my issue clearly, involved the relation between (the order of) factors and coord_flip(), as seems to be the case here.

I get the desired result by adding + xlim(rev(levels(x$variable))) to the ggplot statement:

ggplot(x, aes(x=variable,y=value)) + geom_bar() + 
scale_y_continuous("",formatter="percent") + coord_flip() 
+  xlim(rev(levels(x$variable)))

This reverses the order of factors as found in the original data frame in the x-axis, which will become the y-axis with coord_flip(). Notice that in this particular example, the variable also happen to be in alphabetical order, but specifying an arbitrary order of levels within xlim() should work in general.

How do I reference a cell range from one worksheet to another using excel formulas?

Ok Got it, I downloaded a custom concatenation function and then just referenced its cells

Code

    Function concat(useThis As Range, Optional delim As String) As String
 ' this function will concatenate a range of cells and return one string
 ' useful when you have a rather large range of cells that you need to add up
 Dim retVal, dlm As String
 retVal = ""
 If delim = Null Then
 dlm = ""
 Else
 dlm = delim
 End If
 For Each cell In useThis
 if cstr(cell.value)<>"" and cstr(cell.value)<>" " then
 retVal = retVal & cstr(cell.Value) & dlm
 end if
 Next
 If dlm <> "" Then
 retVal = Left(retVal, Len(retVal) - Len(dlm))
 End If
 concat = retVal
 End Function

What is an unhandled promise rejection?

In my case was Promise with no reject neither resolve, because my Promise function threw an exception. This mistake cause UnhandledPromiseRejectionWarning message.

How to forcefully set IE's Compatibility Mode off from the server-side?

For Node/Express developers you can use middleware and set this via server.

app.use(function(req, res, next) {
  res.setHeader('X-UA-Compatible', 'IE=edge');
  next();
});

How to set environment via `ng serve` in Angular 6

For Angular 2 - 5 refer the article Multiple Environment in angular

For Angular 6 use ng serve --configuration=dev

Note: Refer the same article for angular 6 as well. But wherever you find --env instead use --configuration. That's works well for angular 6.

How to copy folders to docker image from Dockerfile?

Like @Vonc said, there is no possibility to add a command like as of now. The only workaround is to mention the folder, to create it and add contents to it.

# add contents to folder
ADD src $HOME/src

Would create a folder called src in your directory and add contents of your folder src into this.

How do I get the value of a registry key and ONLY the value using powershell

NONE of these answers work for situations where the value name contains spaces, dots, or other characters that are reserved in PowerShell. In that case you have to wrap the name in double quotes as per http://blog.danskingdom.com/accessing-powershell-variables-with-periods-in-their-name/ - for example:

PS> Get-ItemProperty Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7

14.0         : C:\Program Files (x86)\Microsoft Visual Studio 14.0\
12.0         : C:\Program Files (x86)\Microsoft Visual Studio 12.0\
11.0         : C:\Program Files (x86)\Microsoft Visual Studio 11.0\
15.0         : C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PSPath       : Microsoft.PowerShell.Core\Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\V
               S7
PSParentPath : Microsoft.PowerShell.Core\Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS
PSChildName  : VS7
PSProvider   : Microsoft.PowerShell.Core\Registry

If you want to access any of the 14.0, 12.0, 11.0, 15.0 values, the solution from the accepted answer will not work - you will get no output:

PS> (Get-ItemProperty Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7 -Name 15.0).15.0
PS>

What does work is quoting the value name, which you should probably be doing anyway for safety:

PS> (Get-ItemProperty "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7" -Name "15.0")."15.0"
C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PS> 

Thus, the accepted answer should be modified as such:

PS> $key = "Registry::HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7"
PS> $value = "15.0"
PS> (Get-ItemProperty -Path $key -Name $value).$value
C:\Program Files (x86)\Microsoft Visual Studio\2017\Enterprise\
PS> 

This works in PowerShell 2.0 through 5.0 (although you should probably be using Get-ItemPropertyValue in v5).

How can INSERT INTO a table 300 times within a loop in SQL?

Found some different answers that I combined to solve simulair problem:

CREATE TABLE nummer (ID INTEGER PRIMARY KEY, num, text, text2);
WITH RECURSIVE
  for(i) AS (VALUES(1) UNION ALL SELECT i+1 FROM for WHERE i < 1000000)
INSERT INTO nummer SELECT i, i+1, "text" || i, "otherText" || i FROM for;

Adds 1 miljon rows with

  • id increased by one every itteration
  • num one greater then id
  • text concatenated with id-number like: text1, text2 ... text1000000
  • text2 concatenated with id-number like: otherText1, otherText2 ... otherText1000000

Can't bind to 'formGroup' since it isn't a known property of 'form'

I had the same issue with Angular 7. Just import following in your app.module.ts file.

import { FormsModule, ReactiveFormsModule } from '@angular/forms';

Then add FormsModule and ReactiveFormsModule in to your imports array.

imports: [
  FormsModule,
  ReactiveFormsModule
],

How to check for DLL dependency?

In the past (i.e. WinXP days), I used to depend/rely on DLL Dependency Walker (depends.exe) but there are times when I am still not able to determine the DLL issue(s). Ideally, we'd like to find out before runtime by inspections but if that does not resolve it (or taking too much time), you can try enabling the "loader snap" as described on http://blogs.msdn.com/b/junfeng/archive/2006/11/20/debugging-loadlibrary-failures.aspx and https://msdn.microsoft.com/en-us/library/windows/hardware/ff556886(v=vs.85).aspx and briefly mentioned LoadLibrary fails; GetLastError no help

WARNING: I've messed up my Windows in the past fooling around with gflag making it crawl to its knees, you have been forewarned.

enter image description here

Note: "Loader snap" is per-process so the UI enable won't stay checked (use cdb or glfags -i)

How can I backup a remote SQL Server database to a local drive?

I know this is an older post, but for what it's worth, I've found that the "simplest" solution is to just right-click on the database, and select "Tasks" -> "Export Data-tier Application". It's possible that this option is only available because the server is hosted on Azure (from what I remember working with Azure in the past, the .bacpac format was quite common there).

Once that's done, you can right-click on your local server "Databases" list, and use the "Import Data-tier Application" to get the data to your local machine using the .bacpac file.

Just bear in mind the export could take a long time. Took roughly two hours for mine to finish exporting. Import part is much faster, though.

What is a clean, Pythonic way to have multiple constructors in Python?

class Cheese:
    def __init__(self, *args, **kwargs):
        """A user-friendly initialiser for the general-purpose constructor.
        """
        ...

    def _init_parmesan(self, *args, **kwargs):
        """A special initialiser for Parmesan cheese.
        """
        ...

    def _init_gauda(self, *args, **kwargs):
        """A special initialiser for Gauda cheese.
        """
        ...

    @classmethod
    def make_parmesan(cls, *args, **kwargs):
        new = cls.__new__(cls)
        new._init_parmesan(*args, **kwargs)
        return new

    @classmethod
    def make_gauda(cls, *args, **kwargs):
        new = cls.__new__(cls)
        new._init_gauda(*args, **kwargs)
        return new

Python Loop: List Index Out of Range

Try reducing the range of the for loop to range(len(a)-1):

a = [0,1,2,3]
b = []

for i in range(len(a)-1):
    b.append(a[i]+a[i+1])

print(b)

This can also be written as a list comprehension:

b = [a[i] + a[i+1] for i in range(len(a)-1)]
print(b)

Delete last N characters from field in a SQL Server database

This should do it, removing characters from the left by one or however many needed.

lEFT(columnX,LEN(columnX) - 1) AS NewColumnName

How to show the Project Explorer window in Eclipse

i had also encountered this issue. . This Solution worked for me....

windows->navigation->maximize active View or Editor(ctrl + M) . in the screen you can see on left side navigation menus ... now click on those buttons one by one ....you will get your solution...

JS file gets a net::ERR_ABORTED 404 (Not Found)

As mentionned in comments: you need a way to send your static files to the client. This can be achieved with a reverse proxy like Nginx, or simply using express.static().

Put all your "static" (css, js, images) files in a folder dedicated to it, different from where you put your "views" (html files in your case). I'll call it static for the example. Once it's done, add this line in your server code:

app.use("/static", express.static('./static/'));

This will effectively serve every file in your "static" folder via the /static route.

Querying your index.js file in the client thus becomes:

<script src="static/index.js"></script>

How to check for a valid URL in Java?

Judging by the source code for URI, the

public URL(URL context, String spec, URLStreamHandler handler)

constructor does more validation than the other constructors. You might try that one, but YMMV.

Android - Adding at least one Activity with an ACTION-VIEW intent-filter after Updating SDK version 23

this solution work only .if your want to ignore this Warning

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:ignore="GoogleAppIndexingWarning"
    package="com.example.saloononlinesolution">

Alternate background colors for list items

Since you using standard HTML you will need to define separate class for and manual set the rows to the classes.

Configuration with name 'default' not found. Android Studio

Step.1 $ git submodule update

Step.2 To be commented out the dependences of classpass

Adding VirtualHost fails: Access Forbidden Error 403 (XAMPP) (Windows 7)

Okay: This is what I did now and it's solved:

My httpd-vhosts.conf looks like this now:

<VirtualHost dropbox.local:80>
    DocumentRoot "E:/Documenten/Dropbox/Dropbox/dummy-htdocs"
    ServerName dropbox.local
    ErrorLog "logs/dropbox.local-error.log"
    CustomLog "logs/dropbox.local-access.log" combined
    <Directory "E:/Documenten/Dropbox/Dropbox/dummy-htdocs">
        # AllowOverride All      # Deprecated
        # Order Allow,Deny       # Deprecated
        # Allow from all         # Deprecated

        # --New way of doing it
        Require all granted    
    </Directory>
</VirtualHost>

First, I saw that it's necessary to have set the <Directory xx:xx> options. So I put the <Directory > [..] </Directory>-part INSIDE the <VirtualHost > [..] </VirtualHost>. After that, I added AllowOverride AuthConfig Indexes to the <Directory> options.

Now http://localhost also points to the dropbox-virtualhost. So I added dropbox.local to <VirtualHost *:80> which makes it as <VirtualHost dropbox.local:80>

FINALLY it works :D!

I'm a happy man! :) :)

I hope someone else can use this information.

How do I simulate a low bandwidth, high latency environment?

I use NetBalancer on my Windows machine.

http://seriousbit.com/netbalancer/

Updates on 2017-10-07: The last free version of NetBalancer is 9.2.7. The program has a hard-coded expiration date. Before you start the NetBalancer service, you need to turn back the system clock before 2016-10-18. See this article for details.

HTML img tag: title attribute vs. alt attribute?

No, I think alt is better because the purpose of that attribute is to provide "alternate" text in the event that the image cannot be view (whether it be that the image is missing or that the browser itself is incapable of displaying it).

Git Cherry-Pick and Conflicts

Do, I need to resolve all the conflicts before proceeding to next cherry -pick

Yes, at least with the standard git setup. You cannot cherry-pick while there are conflicts.

Furthermore, in general conflicts get harder to resolve the more you have, so it's generally better to resolve them one by one.

That said, you can cherry-pick multiple commits at once, which would do what you are asking for. See e.g. How to cherry-pick multiple commits . This is useful if for example some commits undo earlier commits. Then you'd want to cherry-pick all in one go, so you don't have to resolve conflicts for changes that are undone by later commits.

Further, is it suggested to do cherry-pick or branch merge in this case?

Generally, if you want to keep a feature branch up to date with main development, you just merge master -> feature branch. The main advantage is that a later merge feature branch -> master will be much less painful.

Cherry-picking is only useful if you must exclude some changes in master from your feature branch. Still, this will be painful so I'd try to avoid it.

How to get current time with jQuery

jQuery.now() Returns: Number

Description: Return a number representing the current time.

This method does not accept any arguments.

The $.now() method is a shorthand for the number returned by the expression (new Date).getTime().

http://api.jquery.com/jQuery.now/

It's simple to use Javascript:

var d = new Date();
var time = d.getHours() + ":" + d.getMinutes() + ":" + d.getSeconds();
console.log(time);

Setting up and using environment variables in IntelliJ Idea

In addition to the above answer and restarting the IDE didn't do, try restarting "Jetbrains Toolbox" if you use it, this did it for me

JavaScript chop/slice/trim off last character in string

Be aware that String.prototype.{ split, slice, substr, substring } operate on UTF-16 encoded strings

None of the previous answers are Unicode-aware. Strings are encoded as UTF-16 in most modern JavaScript engines, but higher Unicode code points require surrogate pairs, so older, pre-existing string methods operate on UTF-16 code units, not Unicode code points.

_x000D_
_x000D_
const string = "?";

console.log(string.slice(0, -1)); // "?\ud83e"
console.log(string.substr(0, string.length - 1)); // "?\ud83e"
console.log(string.substring(0, string.length - 1)); // "?\ud83e"
console.log(string.replace(/.$/, "")); // "?\ud83e"
console.log(string.match(/(.*).$/)[1]); // "?\ud83e"

const utf16Chars = string.split("");

utf16Chars.pop();
console.log(utf16Chars.join("")); // "?\ud83e"
_x000D_
_x000D_
_x000D_

In addition, RegExp methods, as suggested in older answers, don’t match line breaks at the end:

_x000D_
_x000D_
const string = "Hello, world!\n";

console.log(string.replace(/.$/, "").endsWith("\n")); // true
console.log(string.match(/(.*).$/) === null); // true
_x000D_
_x000D_
_x000D_


Use the string iterator to iterate characters

Unicode-aware code utilizes the string’s iterator; see Array.from and ... spread. string[Symbol.iterator] can be used (e.g. instead of string) as well.

Also see How to split Unicode string to characters in JavaScript.

Examples:

_x000D_
_x000D_
const string = "?";

console.log(Array.from(string).slice(0, -1).join("")); // "?"
console.log([
  ...string
].slice(0, -1).join("")); // "?"
_x000D_
_x000D_
_x000D_

Use the s and u flags on a RegExp

The dotAll or s flag makes . match line break characters, the unicode or u flag enables certain Unicode-related features. Note that, when using the u flag, you eliminate unnecessary identity escapes, as these are invalid in a u regex, e.g. \[ is fine, as it would start a character class without the backslash, but \: isn’t, as it’s a : with or without the backslash, so you need to remove the backslash.

Examples:

_x000D_
_x000D_
const unicodeString = "?",
  lineBreakString = "Hello, world!\n";

console.log(lineBreakString.replace(/.$/s, "").endsWith("\n")); // false
console.log(lineBreakString.match(/(.*).$/s) === null); // false
console.log(unicodeString.replace(/.$/su, "")); // ?
console.log(unicodeString.match(/(.*).$/su)[1]); // ?

// Now `split` can be made Unicode-aware:

const unicodeCharacterArray = unicodeString.split(/(?:)/su),
  lineBreakCharacterArray = lineBreakString.split(/(?:)/su);

unicodeCharacterArray.pop();
lineBreakCharacterArray.pop();
console.log(unicodeCharacterArray.join("")); // "?"
console.log(lineBreakCharacterArray.join("").endsWith("\n")); // false
_x000D_
_x000D_
_x000D_


Note that some graphemes consist of more than one code point, e.g. ?? which consists of the sequence (U+1F3F3), VS16 (U+FE0F), ZWJ (U+200D), (U+1F308). Here, even Array.from will split this into four “characters”. Matching those is possible with the Unicode property escapes sequence properties proposal.

Open directory dialog

The best way to achieve what you want is to create your own wpf based control , or use a one that was made by other people
why ? because there will be a noticeable performance impact when using the winforms dialog in a wpf application (for some reason)
i recommend this project
https://opendialog.codeplex.com/
or Nuget :

PM> Install-Package OpenDialog

it's very MVVM friendly and it isn't wraping the winforms dialog

MongoNetworkError: failed to connect to server [localhost:27017] on first connect [MongoNetworkError: connect ECONNREFUSED 127.0.0.1:27017]

This had occurred to me and I have found out that it was because of faulty internet connection. If I use the public wifi at my place, which blocks various websites for security reasons, Mongo refuses to connect. But if I were to use my own mobile data, I can connect to the database.

Printf long long int in C with GCC?

You can try settings of code::block, there is a complier..., then you select in C mode.

enter image description here

How to revert a "git rm -r ."?

With Git 2.23+ (August 2019), the proper command to restore files (and the index) woud be to use... git restore (not reset --hard or the confusing git checkout command)

That is:

git restore -s=HEAD --staged --worktree -- .

Or its abbreviated form:

git restore -s@ -SW -- .

What is an abstract class in PHP?

An abstract class is a class that contains at least one abstract method, which is a method without any actual code in it, just the name and the parameters, and that has been marked as "abstract".

The purpose of this is to provide a kind of template to inherit from and to force the inheriting class to implement the abstract methods.

An abstract class thus is something between a regular class and a pure interface. Also interfaces are a special case of abstract classes where ALL methods are abstract.

See this section of the PHP manual for further reference.

Where can I find my Facebook application id and secret key?

You should use the Developer App.

On the right is a section titled "My Applications" from which you can select an application to see its information.

You can also go straight here as well, which will list your apps on the left.

Append values to a set in Python

Define set

a = set()

Use add to append single values

a.add(1)
a.add(2)

Use update to add elements from tuples, sets, lists or frozen-sets

a.update([3,4])

>> print(a)
{1, 2, 3, 4}

If you want to add a tuple or frozen-set itself, use add

a.add((5, 6))

>> print(a)
{1, 2, 3, 4, (5, 6)}

Note: Since set elements must be hashable, and lists are considered mutable, you cannot add a list to a set. You also cannot add other sets to a set. You can however, add the elements from lists and sets as demonstrated with the ".update" method.

[ :Unexpected operator in shell programming

POSIX sh doesn't understand == for string equality, as that is a bash-ism. Use = instead.

The other people saying that brackets aren't supported by sh are wrong, btw.

Loop timer in JavaScript

Note that setTimeout and setInterval are very different functions:

  • setTimeout will execute the code once, after the timeout.
  • setInterval will execute the code forever, in intervals of the provided timeout.

Both functions return a timer ID which you can use to abort the timeout. All you have to do is store that value in a variable and use it as argument to clearTimeout(tid) or clearInterval(tid) respectively.

So, depending on what you want to do, you have two valid choices:

// set timeout
var tid = setTimeout(mycode, 2000);
function mycode() {
  // do some stuff...
  tid = setTimeout(mycode, 2000); // repeat myself
}
function abortTimer() { // to be called when you want to stop the timer
  clearTimeout(tid);
}

or

// set interval
var tid = setInterval(mycode, 2000);
function mycode() {
  // do some stuff...
  // no need to recall the function (it's an interval, it'll loop forever)
}
function abortTimer() { // to be called when you want to stop the timer
  clearInterval(tid);
}

Both are very common ways of achieving the same.

How do I test for an empty JavaScript object?

If ECMAScript 5 support is available, you can use Object.keys():

function isEmpty(obj) {
    return Object.keys(obj).length === 0;
}

For ES3 and older, there's no easy way to do this. You'll have to loop over the properties explicitly:

function isEmpty(obj) {
    for(var prop in obj) {
        if(obj.hasOwnProperty(prop))
            return false;
    }

    return true;
}

Populate nested array in mongoose

As others have noted, Mongoose 4 supports this. It is very important to note that you can recurse deeper than one level too, if needed—though it is not noted in the docs:

Project.findOne({name: req.query.name})
    .populate({
        path: 'threads',
        populate: {
            path: 'messages', 
            model: 'Message',
            populate: {
                path: 'user',
                model: 'User'
            }
        }
    })

How do I change the UUID of a virtual disk?

Same solution as @Al3x for Windows x64, in cmd.exe:

cd %programfiles%\Oracle\VirtualBox

VBoxManage internalcommands sethduuid "full/path/to/.vdi"

This randomizes the UUID of the disk. Pro tip: Right click the .vdi file while holding shift and select "Copy as path" to obtain "full/path/to/.vdi" and enable quick edit in cmd.exe, then right click to paste.

How to take screenshot of a div with JavaScript?

You can't take a screen-shot: it would be an irresponsible security risk to let you do so. However, you can:

  • Do things server-side and generate an image
  • Draw something similar to a Canvas and render that to an image (in a browser that supports it)
  • Use some other drawing library to draw directly to the image (slow, but would work on any browser)

Mvn install or Mvn package

package - takes the compiled code and package it in its distributable format, such as a JAR or WAR file. install - install the package into the local repository, for use as a dependency in other projects locally

How do I access my SSH public key?

The following command will save the SSH key on the clipboard. You only need to paste at the desired location.

cat ~/.ssh/id_rsa.pub | pbcopy

How can I echo HTML in PHP?

echo '
<html>
<body>
</body>
</html>
';

or

echo "<html>\n<body>\n</body>\n</html>\n";

How to print a list with integers without the brackets, commas and no quotes?

If you're using Python 3, or appropriate Python 2.x version with from __future__ import print_function then:

data = [7, 7, 7, 7]
print(*data, sep='')

Otherwise, you'll need to convert to string and print:

print ''.join(map(str, data))

Wildcards in jQuery selectors

When you have a more complex id string the double quotes are mandatory.

For example if you have an id like this: id="2.2", the correct way to access it is: $('input[id="2.2"]')

As much as possible use the double quotes, for safety reasons.

python plot normal distribution

import matplotlib.pyplot as plt
import numpy as np
import scipy.stats as stats
import math

mu = 0
variance = 1
sigma = math.sqrt(variance)
x = np.linspace(mu - 3*sigma, mu + 3*sigma, 100)
plt.plot(x, stats.norm.pdf(x, mu, sigma))
plt.show()

gass distro, mean is 0 variance 1

Is there a method for String conversion to Title Case?

If you want the correct answer according to the latest Unicode standard, you should use icu4j.

UCharacter.toTitleCase(Locale.US, "hello world", null, 0);

Note that this is locale sensitive.

Api Documentation

Implementation

Python script to convert from UTF-8 to ASCII

import codecs

 ...

fichier = codecs.open(filePath, "r", encoding="utf-8")

 ...

fichierTemp = codecs.open("tempASCII", "w", encoding="ascii", errors="ignore")
fichierTemp.write(contentOfFile)

 ...

How do you get the cursor position in a textarea?

If there is no selection, you can use the properties .selectionStart or .selectionEnd (with no selection they're equal).

var cursorPosition = $('#myTextarea').prop("selectionStart");

Note that this is not supported in older browsers, most notably IE8-. There you'll have to work with text ranges, but it's a complete frustration.

I believe there is a library somewhere which is dedicated to getting and setting selections/cursor positions in input elements, though. I can't recall its name, but there seem to be dozens on articles about this subject.

How to disable <br> tags inside <div> by css?

You could alter your CSS to render them less obtrusively, e.g.

div p,
div br {
    display: inline;
}

http://jsfiddle.net/zG9Ax/

or - as my commenter points out:

div br {
    display: none;
}

but then to achieve the example of what you want, you'll need to trim the p down, so:

div br {
    display: none;
}
div p {
    padding: 0;
    margin: 0;
}

http://jsfiddle.net/zG9Ax/1

Remove git mapping in Visual Studio 2015

Go to Control Panel\User Accounts\Credential Manager and select Windows Credential then remove account of git.

Can you explain the HttpURLConnection connection process?

I went through the exercise to capture low level packet exchange, and found that network connection is only triggered by operations like getInputStream, getOutputStream, getResponseCode, getResponseMessage etc.

Here is the packet exchange captured when I try to write a small program to upload file to Dropbox.

enter image description here

Below is my toy program and annotation

    /* Create a connection LOCAL object,
     * the openConnection() function DOES NOT initiate
     * any packet exchange with the remote server.
     * 
     * The configurations only setup the LOCAL
     * connection object properties.
     */
    HttpURLConnection connection = (HttpURLConnection) dst.openConnection();
    connection.setDoOutput(true);
    connection.setRequestMethod("POST");
    ...//headers setup
    byte[] testContent = {0x32, 0x32};

    /**
     * This triggers packet exchange with the remote
     * server to create a link. But writing/flushing
     * to a output stream does not send out any data.
     * 
     * Payload are buffered locally.
     */
    try (BufferedOutputStream outputStream = new BufferedOutputStream(connection.getOutputStream())) {
        outputStream.write(testContent);
        outputStream.flush();
    }

    /**
     * Trigger payload sending to the server.
     * Client get ALL responses (including response code,
     * message, and content payload) 
     */
    int responseCode = connection.getResponseCode();
    System.out.println(responseCode);

    /* Here no further exchange happens with remote server, since
     * the input stream content has already been buffered
     * in previous step
     */
    try (InputStream is = connection.getInputStream()) {
        Scanner scanner = new Scanner(is);
        StringBuilder stringBuilder = new StringBuilder();
        while (scanner.hasNextLine()) {
        stringBuilder.append(scanner.nextLine()).append(System.lineSeparator());
        }
    }

    /**
     * Trigger the disconnection from the server.
     */
    String responsemsg = connection.getResponseMessage();
    System.out.println(responsemsg);
    connection.disconnect();

Intersect Two Lists in C#

If you have objects, not structs (or strings), then you'll have to intersect their keys first, and then select objects by those keys:

var ids = list1.Select(x => x.Id).Intersect(list2.Select(x => x.Id));
var result = list1.Where(x => ids.Contains(x.Id));

Which are more performant, CTE or temporary tables?

I've used both but in massive complex procedures have always found temp tables better to work with and more methodical. CTEs have their uses but generally with small data.

For example I've created sprocs that come back with results of large calculations in 15 seconds yet convert this code to run in a CTE and have seen it run in excess of 8 minutes to achieve the same results.

How to find Control in TemplateField of GridView?

If your GridView is databond, make an index column in the resultset you retrive like this:

select row_number() over(order by YourIdentityColumn asc)-1 as RowIndex, * from YourTable where [Expresion]

In the command control you want to use make the value of CommandArgument property equal to the row index of the DataSet table RowIndex like this:

<asp:LinkButton ID="lbnMsgSubj" runat="server" Text='<%# Eval("MsgSubj") %>' Font-Underline="false" CommandArgument='<%#Eval("RowIndex") %>' />

Use the OnRowCommand event to fire on clicking the link button like this:

<asp:GridView ID="gvwStuMsgBoard" runat="server" AutoGenerateColumns="false" GridLines="Horizontal" BorderColor="Transparent" Width="100%" OnRowCommand="gvwStuMsgBoard_RowCommand">

Finally the code behind you can then do whatever you like when the event is triggered like this:

protected void gvwStuMsgBoard_RowCommand(object sender, GridViewCommandEventArgs e)
{
    Panel pnlMsgBody = (Panel)gvwStuMsgBoard.Rows[Convert.ToInt32(e.CommandArgument)].FindControl("pnlMsgBody");
    if(pnlMsgBody.Visible == false)
    {
        pnlMsgBody.Visible = true;
    }
    else
    {
        pnlMsgBody.Visible = false;
    }
}

What is a good Hash Function?

I'd say that the main rule of thumb is not to roll your own. Try to use something that has been thoroughly tested, e.g., SHA-1 or something along those lines.

jQuery - find child with a specific class

I'm not sure if I understand your question properly, but it shouldn't matter if this div is a child of some other div. You can simply get text from all divs with class bgHeaderH2 by using following code:

$(".bgHeaderH2").text();

How can Bash execute a command in a different directory context?

Use cd in a subshell; the shorthand way to use this kind of subshell is parentheses.

(cd wherever; mycommand ...)

That said, if your command has an environment that it requires, it should really ensure that environment itself instead of putting the onus on anything that might want to use it (unless it's an internal command used in very specific circumstances in the context of a well defined larger system, such that any caller already needs to ensure the environment it requires). Usually this would be some kind of shell script wrapper.

Using C# to check if string contains a string in string array

Three options demonstrated. I prefer to find the third as the most concise.

class Program {
    static void Main(string[] args) {
    string req = "PUT";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("one.1.A");  // IS TRUE
    }
    req = "XPUT";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("one.1.B"); // IS TRUE
    }
    req = "PUTX";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("one.1.C");  // IS TRUE
    }
    req = "UT";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("one.1.D"); // false
    }
    req = "PU";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("one.1.E"); // false
    }
    req = "POST";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("two.1.A"); // IS TRUE
    }
    req = "ASD";
    if ((new string[] {"PUT", "POST"}).Any(s => req.Contains(s))) {
        Console.WriteLine("three.1.A");  // false
    }


    Console.WriteLine("-----");
    req = "PUT";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("one.2.A"); // IS TRUE
    }
    req = "XPUT";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("one.2.B"); // false
    }
    req = "PUTX";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("one.2.C"); // false
    }
    req = "UT";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("one.2.D"); // false
    }
    req = "PU";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("one.2.E"); // false
    }
    req = "POST";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("two.2.A");  // IS TRUE
    }
    req = "ASD";
    if (Array.IndexOf((new string[] {"PUT", "POST"}), req) >= 0)  {
        Console.WriteLine("three.2.A");  // false
    }

    Console.WriteLine("-----");
    req = "PUT";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("one.3.A"); // IS TRUE
    }
    req = "XPUT";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("one.3.B");  // false
    }
    req = "PUTX";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("one.3.C");  // false
    }
    req = "UT";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("one.3.D");  // false
    }
    req = "PU";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("one.3.E");  // false
    }
    req = "POST";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("two.3.A");  // IS TRUE
    }
    req = "ASD";
    if ((new string[] {"PUT", "POST"}.Contains(req)))  {
        Console.WriteLine("three.3.A");  // false
    }

    Console.ReadKey();
    }
}

How to find out "The most popular repositories" on Github?

Ranking by stars or forks is not working. Each promoted or created by a famous company repository is popular at the beginning. Also it is possible to have a number of them which are in trend right now (publications, marketing, events). It doesn't mean that those repositories are useful/popular.

The gitmostwanted.com project (repo at github) analyses GH Archive data in order to highlight the most interesting repositories and exclude others. Just compare the results with mentioned resources.

MYSQL import data from csv using LOAD DATA INFILE

You can load data from a csv or text file. If you have a text file with records from a table, you can load those records within the table. For example if you have a text file, where each row is a record with the values for each column, you can load the records this way.

table.sql

id //field 1

name //field2

table.txt

1,peter

2,daniel

...

--example on windows

LOAD DATA LOCAL INFILE 'C:\\directory_example\\table.txt'
INTO TABLE Table
CHARACTER SET UTF8
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\r\n'; 

Get the device width in javascript

You can get the device screen width via the screen.width property.
Sometimes it's also useful to use window.innerWidth (not typically found on mobile devices) instead of screen width when dealing with desktop browsers where the window size is often less than the device screen size.

Typically, when dealing with mobile devices AND desktop browsers I use the following:

 var width = (window.innerWidth > 0) ? window.innerWidth : screen.width;

PostgreSQL: How to make "case-insensitive" query

You can also read up on the ILIKE keyword. It can be quite useful at times, albeit it does not conform to the SQL standard. See here for more information: http://www.postgresql.org/docs/9.2/static/functions-matching.html

Replacing accented characters php

I found this way to be a good one, without having to worry too much about charsets and arrays, or iconv:

function replace_accents($str) {
   $str = htmlentities($str, ENT_COMPAT, "UTF-8");
   $str = preg_replace('/&([a-zA-Z])(uml|acute|grave|circ|tilde|ring);/','$1',$str);
   return html_entity_decode($str);
}

What is the bower (and npm) version syntax?

Bower uses semver syntax, but here are a few quick examples:

You can install a specific version:

$ bower install jquery#1.11.1

You can use ~ to specify 'any version that starts with this':

$ bower install jquery#~1.11

You can specify multiple version requirements together:

$ bower install "jquery#<2.0 >1.10"

Eclipse does not start when I run the exe?

If its a Java version problem, you can edit the eclipse.ini file and assign the compatible version to the application through adding these lines:

windows example:

-vm
C:\jdk1.7.0_21\bin\javaw.exe 

for more information: https://wiki.eclipse.org/Eclipse.ini