Programs & Examples On #Argotic

A powerful and extensible .NET web content syndication framework for RSS, Atom, OPML, APML, BlogML, RSD and more. The Argotic Syndication Framework is a Microsoft .NET class library framework that enables developers to easily consume and/or generate syndicated content from within their own applications.

android lollipop toolbar: how to hide/show the toolbar while scrolling?

I've been trying to implement the same behavior, here is the brunt of code showing and hiding the toolbar (put in whatever class containing your RecyclerView):

int toolbarMarginOffset = 0

private int dp(int inPixels){
    return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, inPixels, getApplicationContext().getResources().getDisplayMetrics());
}

public RecyclerView.OnScrollListener onScrollListenerToolbarHide = new RecyclerView.OnScrollListener() {
    @Override
    public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
        super.onScrolled(recyclerView, dx, dy);
        toolbarMarginOffset += dy;
        if(toolbarMarginOffset>dp(48)){
            toolbarMarginOffset = dp(48);
        }
        if(toolbarMarginOffset<0){
            toolbarMarginOffset = 0;
        }
        ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams)toolbar.getLayoutParams();
        params.topMargin = -1*toolbarMarginOffset; 
        toolbar.setLayoutParams(params);
    }
};

I've included the dp function to convert from pixels to dp but obviously set it to whatever your toolbar height is. (replace dp(48) with your toolbar height)

Where-ever you setup your RecyclerView include this:

yourListView.setOnScrollListener(onScrollListenerToolbarHide);

However, there are a couple additional issues if you are also using a SwipeRefreshLayout.

I've had to set the marginTop of the first element in the adapter for the RecyclerView to the Toolbar's height plus original offset. (A bit of a hack I know). The reason for this is I found that if I changed my above code to include changing the marginTop of the recyclerView while scrolling it was a jittery experience. So that's how I overcame it. So basically setup your layout so that your toolbar is floating on top of the RecyclerView (clipping it) Something like this (in onBindViewHolder of your custom RecyclerView adapter) :

 if(position==0){
     ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams)holder.card.getLayoutParams();
     // params.height = ViewGroup.LayoutParams.WRAP_CONTENT;
     params.topMargin = dp(10+48);
 }

And lastly, since there is a large offset the RecyclerViews refresh circle will be clipped, so you'll need to offset it (back in onCreate of your class holding your RecyclerView):

swipeLayout.setProgressViewOffset(true,dp(48),dp(96));

I hope this helps someone. Its my first detailed answer so I hope I was detailed enough.

Bitbucket fails to authenticate on git pull

I clicked on this button and it worked for me.

Here is the screenshot

Server http:/localhost:8080 requires a user name and a password. The server says: XDB

Just change the port number used e.g. 8000 then call the http://localhost:8080

vertical alignment of text element in SVG

attr("dominant-baseline", "central")

How to set MimeBodyPart ContentType to "text/html"?

There is a method setText() which takes 3 arguments :

public void setText(String text, String charset, String subtype)
    throws MessagingException

Parameters:

text - the text content to set
charset - the charset to use for the text
subtype - the MIME subtype to use (e.g., "html")

NOTE: the subtype takes text after / in MIME types so for ex.

  • text/html would be html
  • text/css would be css
  • and so on..

How to use a RELATIVE path with AuthUserFile in htaccess?

I know this is an old question, but I just searched for the same thing and probably there are many others searching for a quick, mobile solution. Here is what I finally come up with:

# We set production environment by default
SetEnv PROD_ENV 1

<IfDefine DEV_ENV>
  # If 'DEV_ENV' has been defined, then unset the PROD_ENV
  UnsetEnv PROD_ENV

  AuthType Basic
  AuthName "Protected Area"
  AuthUserFile /var/www/foo.local/.htpasswd
  Require valid-user
</IfDefine>

<IfDefine PROD_ENV>
  AuthType Basic
  AuthName "Protected Area"
  AuthUserFile /home/foo/public_html/.htpasswd
  Require valid-user
</IfDefine>

How to install bcmath module?

If you have installed php 7.1 then this line work on your system.

sudo apt install php7.1-bcmath

check your php version in your system on ubuntu 16.04

php -v

and then result show there..

PHP 7.1.x+ubuntu16.04.1+deb.sury.org+1 (cli) (built: Aug 19 2018 07:16:12) ( NTS ) Copyright (c) 1997-2018 The PHP Group Zend Engine v3.2.0, Copyright (c) 1998-2018 Zend Technologies with Zend OPcache v7.2.9-1+ubuntu16.04.1+deb.sury.org+1, Copyright (c) 1999-2018, by Zend Technologies

Parse Error: Adjacent JSX elements must be wrapped in an enclosing tag

If you don't want to wrap it in another div as other answers have suggested, you can also wrap it in an array and it will work.

// Wrong!
return (  
   <Comp1 />
   <Comp2 />
)

It can be written as:

// Correct!
return (  
    [<Comp1 />,
    <Comp2 />]
)

Please note that the above will generate a warning: Warning: Each child in an array or iterator should have a unique "key" prop. Check the render method of 'YourComponent'.

This can be fixed by adding a key attribute to the components, if manually adding these add it like:

return (  
    [<Comp1 key="0" />,
    <Comp2 key="1" />]
)

Here is some more information on keys:Composition vs Inheritance

explicit casting from super class to subclass

Elaborating the answer given by Michael Berry.

Dog d = (Dog)Animal; //Compiles but fails at runtime

Here you are saying to the compiler "Trust me. I know d is really referring to a Dog object" although it's not. Remember compiler is forced to trust us when we do a downcast.

The compiler only knows about the declared reference type. The JVM at runtime knows what the object really is.

So when the JVM at the runtime figures out that the Dog d is actually referring to an Animal and not a Dog object it says. Hey... you lied to the compiler and throws a big fat ClassCastException.

So if you are downcasting you should use instanceof test to avoid screwing up.

if (animal instanceof Dog) { Dog dog = (Dog) animal; }

Now a question comes to our mind. Why the hell compiler is allowing the downcast when eventually it is going to throw a java.lang.ClassCastException?

The answer is that all the compiler can do is verify that the two types are in the same inheritance tree, so depending on whatever code might have come before the downcast, it's possible that animal is of type dog.

The compiler must allow things that might possible work at runtime.

Consider the following code snipet:

public static void main(String[] args) 
{   
    Dog d = getMeAnAnimal();// ERROR: Type mismatch: cannot convert Animal to Dog
    Dog d = (Dog)getMeAnAnimal(); // Downcast works fine. No ClassCastException :)
    d.eat();

}

private static Animal getMeAnAnimal()
{
    Animal animal = new Dog();
    return animal;
}

However, if the compiler is sure that the cast would not possible work, compilation will fail. I.E. If you try to cast objects in different inheritance hierarchies

String s = (String)d; // ERROR : cannot cast for Dog to String

Unlike downcasting, upcasting works implicitly because when you upcast you are implicitly restricting the number of method you can invoke, as opposite to downcasting, which implies that later on, you might want to invoke a more specific method.

Dog d = new Dog(); Animal animal1 = d; // Works fine with no explicit cast Animal animal2 = (Animal) d; // Works fine with n explicit cast

Both of the above upcast will work fine without any exception because a Dog IS-A Animal, anithing an Animal can do, a dog can do. But it's not true vica-versa.

True/False vs 0/1 in MySQL

Bit is also an option if tinyint isn't to your liking. A few links:

Not surprisingly, more info about numeric types is available in the manual.

One more link: http://blog.mclaughlinsoftware.com/2010/02/26/mysql-boolean-data-type/

And a quote from the comment section of the article above:

  • TINYINT(1) isn’t a synonym for bit(1).
  • TINYINT(1) can store -9 to 9.
  • TINYINT(1) UNSIGNED: 0-9
  • BIT(1): 0, 1. (Bit, literally).

Edit: This edit (and answer) is only remotely related to the original question...

Additional quotes by Justin Rovang and the author maclochlainn (comment section of the linked article).

Excuse me, seems I’ve fallen victim to substr-ism: TINYINT(1): -128-+127 TINYINT(1) UNSIGNED: 0-255 (Justin Rovang 25 Aug 11 at 4:32 pm)

True enough, but the post was about what PHPMyAdmin listed as a Boolean, and there it only uses 0 or 1 from the entire wide range of 256 possibilities. (maclochlainn 25 Aug 11 at 11:35 pm)

Difference between the System.Array.CopyTo() and System.Array.Clone()

The Clone() method returns a new array (a shallow copy) object containing all the elements in the original array. The CopyTo() method copies the elements into another existing array. Both perform a shallow copy. A shallow copy means the contents (each array element) contains references to the same object as the elements in the original array. A deep copy (which neither of these methods performs) would create a new instance of each element's object, resulting in a different, yet identical object.

So the difference are :

1- CopyTo require to have a destination array when Clone return a new array.
2- CopyTo let you specify an index (if required) to the destination array.
Edit:

Remove the wrong example.

Check if key exists in JSON object using jQuery

if(typeof theObject['key'] != 'undefined'){
     //key exists, do stuff
}

//or

if(typeof theObject.key != 'undefined'){
    //object exists, do stuff
}

I'm writing here because no one seems to give the right answer..

I know it's old...

Somebody might question the same thing..

What is your most productive shortcut with Vim?

Session

a. save session

:mks sessionname

b. force save session

:mks! sessionname

c. load session

gvim or vim -S sessionname


Adding and Subtracting

a. Adding and Subtracting

CTRL-A ;Add [count] to the number or alphabetic character at or after the cursor. {not in Vi

CTRL-X ;Subtract [count] from the number or alphabetic character at or after the cursor. {not in Vi}

b. Window key unmapping

In window, Ctrl-A already mapped for whole file selection you need to unmap in rc file. mark mswin.vim CTRL-A mapping part as comment or add your rc file with unmap

c. With Macro

The CTRL-A command is very useful in a macro. Example: Use the following steps to make a numbered list.

  1. Create the first list entry, make sure it starts with a number.
  2. qa - start recording into buffer 'a'
  3. Y - yank the entry
  4. p - put a copy of the entry below the first one
  5. CTRL-A - increment the number
  6. q - stop recording
  7. @a - repeat the yank, put and increment times

Android Fatal signal 11 (SIGSEGV) at 0x636f7d89 (code=1). How can it be tracked down?

I also got this error many times and I solved it. This error will be faced in case of memory management in native side.

Your application is accessing memory outside of its address space. This is most likely an invalid pointer access. SIGSEGV = segmentation fault in native code. Since it is not occurring in Java code you won't see a stack trace with details. However, you may still see some stack trace information in the logcat if you look around a bit after the application process crashes. It will not tell you the line number within the file, but will tell you which object files and addresses were in use in the call chain. From there you can often figure out which area of the code is problematic. You can also setup a gdb native connection to the target process and catch it in the debugger.

Change Active Menu Item on Page Scroll?

Just check my Code and Sniper and demo link :

    // Basice Code keep it 
    $(document).ready(function () {
        $(document).on("scroll", onScroll);

        //smoothscroll
        $('a[href^="#"]').on('click', function (e) {
            e.preventDefault();
            $(document).off("scroll");

            $('a').each(function () {
                $(this).removeClass('active');
            })
            $(this).addClass('active');

            var target = this.hash,
                menu = target;
            $target = $(target);
            $('html, body').stop().animate({
                'scrollTop': $target.offset().top+2
            }, 500, 'swing', function () {
                window.location.hash = target;
                $(document).on("scroll", onScroll);
            });
        });
    });

// Use Your Class or ID For Selection 

    function onScroll(event){
        var scrollPos = $(document).scrollTop();
        $('#menu-center a').each(function () {
            var currLink = $(this);
            var refElement = $(currLink.attr("href"));
            if (refElement.position().top <= scrollPos && refElement.position().top + refElement.height() > scrollPos) {
                $('#menu-center ul li a').removeClass("active");
                currLink.addClass("active");
            }
            else{
                currLink.removeClass("active");
            }
        });
    }

demo live

_x000D_
_x000D_
$(document).ready(function () {_x000D_
    $(document).on("scroll", onScroll);_x000D_
    _x000D_
    //smoothscroll_x000D_
    $('a[href^="#"]').on('click', function (e) {_x000D_
        e.preventDefault();_x000D_
        $(document).off("scroll");_x000D_
        _x000D_
        $('a').each(function () {_x000D_
            $(this).removeClass('active');_x000D_
        })_x000D_
        $(this).addClass('active');_x000D_
      _x000D_
        var target = this.hash,_x000D_
            menu = target;_x000D_
        $target = $(target);_x000D_
        $('html, body').stop().animate({_x000D_
            'scrollTop': $target.offset().top+2_x000D_
        }, 500, 'swing', function () {_x000D_
            window.location.hash = target;_x000D_
            $(document).on("scroll", onScroll);_x000D_
        });_x000D_
    });_x000D_
});_x000D_
_x000D_
function onScroll(event){_x000D_
    var scrollPos = $(document).scrollTop();_x000D_
    $('#menu-center a').each(function () {_x000D_
        var currLink = $(this);_x000D_
        var refElement = $(currLink.attr("href"));_x000D_
        if (refElement.position().top <= scrollPos && refElement.position().top + refElement.height() > scrollPos) {_x000D_
            $('#menu-center ul li a').removeClass("active");_x000D_
            currLink.addClass("active");_x000D_
        }_x000D_
        else{_x000D_
            currLink.removeClass("active");_x000D_
        }_x000D_
    });_x000D_
}
_x000D_
body, html {_x000D_
    margin: 0;_x000D_
    padding: 0;_x000D_
    height: 100%;_x000D_
    width: 100%;_x000D_
}_x000D_
.menu {_x000D_
    width: 100%;_x000D_
    height: 75px;_x000D_
    background-color: rgba(0, 0, 0, 1);_x000D_
    position: fixed;_x000D_
    background-color:rgba(4, 180, 49, 0.6);_x000D_
    -webkit-transition: all 0.4s ease;_x000D_
    -moz-transition: all 0.4s ease;_x000D_
    -o-transition: all 0.4s ease;_x000D_
    transition: all 0.4s ease;_x000D_
}_x000D_
.light-menu {_x000D_
    width: 100%;_x000D_
    height: 75px;_x000D_
    background-color: rgba(255, 255, 255, 1);_x000D_
    position: fixed;_x000D_
    background-color:rgba(4, 180, 49, 0.6);_x000D_
    -webkit-transition: all 0.4s ease;_x000D_
    -moz-transition: all 0.4s ease;_x000D_
    -o-transition: all 0.4s ease;_x000D_
    transition: all 0.4s ease;_x000D_
}_x000D_
#menu-center {_x000D_
    width: 980px;_x000D_
    height: 75px;_x000D_
    margin: 0 auto;_x000D_
}_x000D_
#menu-center ul {_x000D_
    margin: 0 0 0 0;_x000D_
}_x000D_
#menu-center ul li a{_x000D_
  padding: 32px 40px;_x000D_
}_x000D_
#menu-center ul li {_x000D_
    list-style: none;_x000D_
    margin: 0 0 0 -4px;_x000D_
    display: inline;_x000D_
_x000D_
}_x000D_
.active, #menu-center ul li a:hover  {_x000D_
    font-family:'Droid Sans', serif;_x000D_
    font-size: 14px;_x000D_
    color: #fff;_x000D_
    text-decoration: none;_x000D_
    line-height: 50px;_x000D_
 background-color: rgba(0, 0, 0, 0.12);_x000D_
 padding: 32px 40px;_x000D_
_x000D_
}_x000D_
a {_x000D_
    font-family:'Droid Sans', serif;_x000D_
    font-size: 14px;_x000D_
    color: black;_x000D_
    text-decoration: none;_x000D_
    line-height: 72px;_x000D_
}_x000D_
#home {_x000D_
    background-color: #286090;_x000D_
    height: 100vh;_x000D_
    width: 100%;_x000D_
    overflow: hidden;_x000D_
}_x000D_
#portfolio {_x000D_
    background: gray; _x000D_
    height: 100vh;_x000D_
    width: 100%;_x000D_
}_x000D_
#about {_x000D_
    background-color: blue;_x000D_
    height: 100vh;_x000D_
    width: 100%;_x000D_
}_x000D_
#contact {_x000D_
    background-color: rgb(154, 45, 45);_x000D_
    height: 100vh;_x000D_
    width: 100%;_x000D_
}
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<!-- <div class="container"> --->_x000D_
   <div class="m1 menu">_x000D_
   <div id="menu-center">_x000D_
    <ul>_x000D_
     <li><a class="active" href="#home">Home</a>_x000D_
_x000D_
     </li>_x000D_
     <li><a href="#portfolio">Portfolio</a>_x000D_
_x000D_
     </li>_x000D_
     <li><a href="#about">About</a>_x000D_
_x000D_
     </li>_x000D_
     <li><a href="#contact">Contact</a>_x000D_
_x000D_
     </li>_x000D_
    </ul>_x000D_
   </div>_x000D_
   </div>_x000D_
   <div id="home"></div>_x000D_
   <div id="portfolio"></div>_x000D_
   <div id="about"></div>_x000D_
   <div id="contact"></div>
_x000D_
_x000D_
_x000D_

How to parse a CSV file using PHP

I been seeking the same thing without using some unsupported PHP class. Excel CSV dosn't always use the quote separators and escapes the quotes using "" because the algorithm was probably made back the 80's or something. After looking at several .csv parsers in the comments section on PHP.NET, I seen ones that even used callbacks or eval'd code and they either didnt work like needed or simply didnt work at all. So, I wrote my own routines for this and they work in the most basic PHP configuration. The array keys can either be numeric or named as the fields given in the header row. Hope this helps.

    function SW_ImplodeCSV(array $rows, $headerrow=true, $mode='EXCEL', $fmt='2D_FIELDNAME_ARRAY')
    // SW_ImplodeCSV - returns 2D array as string of csv(MS Excel .CSV supported)
    // AUTHOR: [email protected]
    // RELEASED: 9/21/13 BETA
      { $r=1; $row=array(); $fields=array(); $csv="";
        $escapes=array('\r', '\n', '\t', '\\', '\"');  //two byte escape codes
        $escapes2=array("\r", "\n", "\t", "\\", "\""); //actual code

        if($mode=='EXCEL')// escape code = ""
         { $delim=','; $enclos='"'; $rowbr="\r\n"; }
        else //mode=STANDARD all fields enclosed
           { $delim=','; $enclos='"'; $rowbr="\r\n"; }

          $csv=""; $i=-1; $i2=0; $imax=count($rows);

          while( $i < $imax )
          {
            // get field names
            if($i == -1)
             { $row=$rows[0];
               if($fmt=='2D_FIELDNAME_ARRAY')
                { $i2=0; $i2max=count($row);
                  while( list($k, $v) = each($row) )
                   { $fields[$i2]=$k;
                     $i2++;
                   }
                }
               else //if($fmt='2D_NUMBERED_ARRAY')
                { $i2=0; $i2max=(count($rows[0]));
                  while($i2<$i2max)
                   { $fields[$i2]=$i2;
                     $i2++;
                   }
                }

               if($headerrow==true) { $row=$fields; }
               else                 { $i=0; $row=$rows[0];}
             }
            else
             { $row=$rows[$i];
             }

            $i2=0;  $i2max=count($row); 
            while($i2 < $i2max)// numeric loop (order really matters here)
            //while( list($k, $v) = each($row) )
             { if($i2 != 0) $csv=$csv.$delim;

               $v=$row[$fields[$i2]];

               if($mode=='EXCEL') //EXCEL 2quote escapes
                    { $newv = '"'.(str_replace('"', '""', $v)).'"'; }
               else  //STANDARD
                    { $newv = '"'.(str_replace($escapes2, $escapes, $v)).'"'; }
               $csv=$csv.$newv;
               $i2++;
             }

            $csv=$csv."\r\n";

            $i++;
          }

         return $csv;
       }

    function SW_ExplodeCSV($csv, $headerrow=true, $mode='EXCEL', $fmt='2D_FIELDNAME_ARRAY')
     { // SW_ExplodeCSV - parses CSV into 2D array(MS Excel .CSV supported)
       // AUTHOR: [email protected]
       // RELEASED: 9/21/13 BETA
       //SWMessage("SW_ExplodeCSV() - CALLED HERE -");
       $rows=array(); $row=array(); $fields=array();// rows = array of arrays

       //escape code = '\'
       $escapes=array('\r', '\n', '\t', '\\', '\"');  //two byte escape codes
       $escapes2=array("\r", "\n", "\t", "\\", "\""); //actual code

       if($mode=='EXCEL')
        {// escape code = ""
          $delim=','; $enclos='"'; $esc_enclos='""'; $rowbr="\r\n";
        }
       else //mode=STANDARD 
        {// all fields enclosed
          $delim=','; $enclos='"'; $rowbr="\r\n";
        }

       $indxf=0; $indxl=0; $encindxf=0; $encindxl=0; $enc=0; $enc1=0; $enc2=0; $brk1=0; $rowindxf=0; $rowindxl=0; $encflg=0;
       $rowcnt=0; $colcnt=0; $rowflg=0; $colflg=0; $cell="";
       $headerflg=0; $quotedflg=0;
       $i=0; $i2=0; $imax=strlen($csv);   

       while($indxf < $imax)
         {
           //find first *possible* cell delimiters
           $indxl=strpos($csv, $delim, $indxf);  if($indxl===false) { $indxl=$imax; }
           $encindxf=strpos($csv, $enclos, $indxf); if($encindxf===false) { $encindxf=$imax; }//first open quote
           $rowindxl=strpos($csv, $rowbr, $indxf); if($rowindxl===false) { $rowindxl=$imax; }

           if(($encindxf>$indxl)||($encindxf>$rowindxl))
            { $quoteflg=0; $encindxf=$imax; $encindxl=$imax;
              if($rowindxl<$indxl) { $indxl=$rowindxl; $rowflg=1; }
            }
           else 
            { //find cell enclosure area (and real cell delimiter)
              $quoteflg=1;
              $enc=$encindxf; 
              while($enc<$indxl) //$enc = next open quote
               {// loop till unquoted delim. is found
                 $enc=strpos($csv, $enclos, $enc+1); if($enc===false) { $enc=$imax; }//close quote
                 $encindxl=$enc; //last close quote
                 $indxl=strpos($csv, $delim, $enc+1); if($indxl===false)  { $indxl=$imax; }//last delim.
                 $enc=strpos($csv, $enclos, $enc+1); if($enc===false) { $enc=$imax; }//open quote
                 if(($indxl==$imax)||($enc==$imax)) break;
               }
              $rowindxl=strpos($csv, $rowbr, $enc+1); if($rowindxl===false) { $rowindxl=$imax; }
              if($rowindxl<$indxl) { $indxl=$rowindxl; $rowflg=1; }
            }

           if($quoteflg==0)
            { //no enclosured content - take as is
              $colflg=1;
              //get cell 
             // $cell=substr($csv, $indxf, ($indxl-$indxf)-1);
              $cell=substr($csv, $indxf, ($indxl-$indxf));
            }
           else// if($rowindxl > $encindxf)
            { // cell enclosed
              $colflg=1;

             //get cell - decode cell content
              $cell=substr($csv, $encindxf+1, ($encindxl-$encindxf)-1);

              if($mode=='EXCEL') //remove EXCEL 2quote escapes
                { $cell=str_replace($esc_enclos, $enclos, $cell);
                }
              else //remove STANDARD esc. sceme
                { $cell=str_replace($escapes, $escapes2, $cell);
                }
            }

           if($colflg)
            {// read cell into array
              if( ($fmt=='2D_FIELDNAME_ARRAY') && ($headerflg==1) )
               { $row[$fields[$colcnt]]=$cell; }
              else if(($fmt=='2D_NUMBERED_ARRAY')||($headerflg==0))
               { $row[$colcnt]=$cell; } //$rows[$rowcnt][$colcnt] = $cell;

              $colcnt++; $colflg=0; $cell="";
              $indxf=$indxl+1;//strlen($delim);
            }
           if($rowflg)
            {// read row into big array
              if(($headerrow) && ($headerflg==0))
                {  $fields=$row;
                   $row=array();
                   $headerflg=1;
                }
              else
                { $rows[$rowcnt]=$row;
                  $row=array();
                  $rowcnt++; 
                }
               $colcnt=0; $rowflg=0; $cell="";
               $rowindxf=$rowindxl+2;//strlen($rowbr);
               $indxf=$rowindxf;
            }

           $i++;
           //SWMessage("SW_ExplodeCSV() - colcnt = ".$colcnt."   rowcnt = ".$rowcnt."   indxf = ".$indxf."   indxl = ".$indxl."   rowindxf = ".$rowindxf);
           //if($i>20) break;
         }

       return $rows;
     }

...bob can now go back to his speadsheets

IE and Edge fix for object-fit: cover;

There is no rule to achieve that using CSS only, besides the object-fit (that you are currently using), which has partial support in EDGE1 so if you want to use this in IE, you have to use a object-fit polyfill in case you want to use just the element img, otherwise you have to do some workarounds.

You can see the the object-fit support here

UPDATE(2019)

You can use a simple JS snippet to detect if the object-fit is supported and then replace the img for a svg

_x000D_
_x000D_
//ES6 version
if ('objectFit' in document.documentElement.style === false) {
    document.addEventListener('DOMContentLoaded', () => {
        document.querySelectorAll('img[data-object-fit]').forEach(image => {
            (image.runtimeStyle || image.style).background = `url("${image.src}") no-repeat 50%/${image.currentStyle ? image.currentStyle['object-fit'] : image.getAttribute('data-object-fit')}`
            image.src = `data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='${image.width}' height='${image.height}'%3E%3C/svg%3E`
        })
    })
}

//ES5 version transpiled from code above with BabelJS
if ('objectFit' in document.documentElement.style === false) {
    document.addEventListener('DOMContentLoaded', function() {
        document.querySelectorAll('img[data-object-fit]').forEach(function(image) {
            (image.runtimeStyle || image.style).background = "url(\"".concat(image.src, "\") no-repeat 50%/").concat(image.currentStyle ? image.currentStyle['object-fit'] : image.getAttribute('data-object-fit'));
            image.src = "data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='".concat(image.width, "' height='").concat(image.height, "'%3E%3C/svg%3E");
        });
    });
}
_x000D_
img {
  display: inline-flex;
  width: 175px;
  height: 175px;
  margin-right: 10px;
  border: 1px solid red
}

[data-object-fit='cover'] {
  object-fit: cover
}

[data-object-fit='contain'] {
  object-fit: contain
}
_x000D_
<img data-object-fit='cover' src='//picsum.photos/1200/600' />
<img data-object-fit='contain' src='//picsum.photos/1200/600' />
<img src='//picsum.photos/1200/600' />
_x000D_
_x000D_
_x000D_

UPDATE(2018)

1 - EDGE has now partial support for object-fit since version 16, and by partial, it means only works in img element (future version 18 still has only partial support)

SS

phpMyAdmin Error: The mbstring extension is missing. Please check your PHP configuration

I see this error after I disabled php5.6 and enabled php7.3 in ubuntu18.0.4

so i reverse it and problem resolved :DDD

Django Template Variables and Javascript

I was facing simillar issue and answer suggested by S.Lott worked for me.

<script type="text/javascript"> 
   var a = "{{someDjangoVariable}}"
</script>

However I would like to point out major implementation limitation here. If you are planning to put your javascript code in different file and include that file in your template. This won't work.

This works only when you main template and javascript code is in same file. Probably django team can address this limitation.

WARNING: Can't verify CSRF token authenticity rails

  1. Make sure that you have <%= csrf_meta_tag %> in your layout
  2. Add a beforeSend to include the csrf-token in the ajax request to set the header. This is only required for post requests.

The code to read the csrf-token is available in the rails/jquery-ujs, so imho it is easiest to just use that, as follows:

$.ajax({
  url: url,
  method: 'post',
  beforeSend: $.rails.CSRFProtection,
  data: {
    // ...
  }
})

Facebook Architecture

Well Facebook has undergone MANY many changes and it wasn't originally designed to be efficient. It was designed to do it's job. I have absolutely no idea what the code looks like and you probably won't find much info about it (for obvious security and copyright reasons), but just take a look at the API. Look at how often it changes and how much of it doesn't work properly, anymore, or at all.

I think the biggest ace up their sleeve is the Hiphop. http://developers.facebook.com/blog/post/358 You can use HipHop yourself: https://github.com/facebook/hiphop-php/wiki

But if you ask me it's a very ambitious and probably time wasting task. Hiphop only supports so much, it can't simply convert everything to C++. So what does this tell us? Well, it tells us that Facebook is NOT fully taking advantage of the PHP language. It's not using the latest 5.3 and I'm willing to bet there's still a lot that is PHP 4 compatible. Otherwise, they couldn't use HipHop. HipHop IS A GOOD IDEA and needs to grow and expand, but in it's current state it's not really useful for that many people who are building NEW PHP apps.

There's also PHP to JAVA via things like Resin/Quercus. Again, it doesn't support everything...

Another thing to note is that if you use any non-standard PHP module, you aren't going to be able to convert that code to C++ or Java either. However...Let's take a look at PHP modules. They are ARE compiled in C++. So if you can build PHP modules that do things (like parse XML, etc.) then you are basically (minus some interaction) working at the same speed. Of course you can't just make a PHP module for every possible need and your entire app because you would have to recompile and it would be much more difficult to code, etc.

However...There are some handy PHP modules that can help with speed concerns. Though at the end of the day, we have this awesome thing known as "the cloud" and with it, we can scale our applications (PHP included) so it doesn't matter as much anymore. Hardware is becoming cheaper and cheaper. Amazon just lowered it's prices (again) speaking of.

So as long as you code your PHP app around the idea that it will need to one day scale...Then I think you're fine and I'm not really sure I'd even look at Facebook and what they did because when they did it, it was a completely different world and now trying to hold up that infrastructure and maintain it...Well, you get things like HipHop.

Now how is HipHop going to help you? It won't. It can't. You're starting fresh, you can use PHP 5.3. I'd highly recommend looking into PHP 5.3 frameworks and all the new benefits that PHP 5.3 brings to the table along with the SPL libraries and also think about your database too. You're most likely serving up content from a database, so check out MongoDB and other types of databases that are schema-less and document-oriented. They are much much faster and better for the most "common" type of web site/app.

Look at NEW companies like Foursquare and Smugmug and some other companies that are utilizing NEW technology and HOW they are using it. For as successful as Facebook is, I honestly would not look at them for "how" to build an efficient web site/app. I'm not saying they don't have very (very) talented people that work there that are solving (their) problems creatively...I'm also not saying that Facebook isn't a great idea in general and that it's not successful and that you shouldn't get ideas from it....I'm just saying that if you could view their entire source code, you probably wouldn't benefit from it.

Entity Framework 5 Updating a Record

There are some really good answers given already, but I wanted to throw in my two cents. Here is a very simple way to convert a view object into a entity. The simple idea is that only the properties that exist in the view model get written to the entity. This is similar to @Anik Islam Abhi's answer, but has null propagation.

public static T MapVMUpdate<T>(object updatedVM, T original)
{
    PropertyInfo[] originalProps = original.GetType().GetProperties();
    PropertyInfo[] vmProps = updatedVM.GetType().GetProperties();
    foreach (PropertyInfo prop in vmProps)
    {
        PropertyInfo projectProp = originalProps.FirstOrDefault(x => x.Name == prop.Name);
        if (projectProp != null)
        {
            projectProp.SetValue(original, prop.GetValue(updatedVM));
        }
    }
    return original;
}

Pros

  • Views don't need to have all the properties of the entity.
  • You never have to update code when you add remove a property to a view.
  • Completely generic

Cons

  • 2 hits on the database, one to load the original entity, and one to save it.

To me the simplicity and low maintenance requirements of this approach outweigh the added database call.

number of values in a list greater than a certain number

You can create a smaller intermediate result like this:

>>> j = [4, 5, 6, 7, 1, 3, 7, 5]
>>> len([1 for i in j if i > 5])
3

Detect rotation of Android phone in the browser with JavaScript

You could always listen to the window resize event. If, on that event, the window went from being taller than it is wide to wider than it is tall (or vice versa), you can be pretty sure the phone orientation was just changed.

Converting from hex to string

string str = "47-61-74-65-77-61-79-53-65-72-76-65-72";
string[] parts = str.Split('-');

foreach (string val in parts)
{ 
    int x;
    if (int.TryParse(val, out x))
    {
         Console.Write(string.Format("{0:x2} ", x);
    }
}
Console.WriteLine();

You can split the string at the -
Convert the text to ints (int.TryParse)
Output the int as a hex string {0:x2}

How to dismiss keyboard iOS programmatically when pressing return

Swift 2 :

this is what is did to do every thing !

close keyboard with Done button or Touch outSide ,Next for go to next input.

First Change TextFiled Return Key To Next in StoryBoard.

override func viewDidLoad() {
  txtBillIdentifier.delegate = self
  txtBillIdentifier.tag = 1
  txtPayIdentifier.delegate  = self
  txtPayIdentifier.tag  = 2

  let tap = UITapGestureRecognizer(target: self, action: "onTouchGesture")
  self.view.addGestureRecognizer(tap)

}

func textFieldShouldReturn(textField: UITextField) -> Bool {
   if(textField.returnKeyType == UIReturnKeyType.Default) {
       if let next = textField.superview?.viewWithTag(textField.tag+1) as? UITextField {
           next.becomeFirstResponder()
           return false
       }
   }
   textField.resignFirstResponder()
   return false
}

func onTouchGesture(){
    self.view.endEditing(true)
}

Strip HTML from Text JavaScript

A safer way to strip the html with jQuery is to first use jQuery.parseHTML to create a DOM, ignoring any scripts, before letting jQuery build an element and then retrieving only the text.

function stripHtml(unsafe) {
    return $($.parseHTML(unsafe)).text();
}

Can safely strip html from:

<img src="unknown.gif" onerror="console.log('running injections');">

And other exploits.

nJoy!

How to search for a file in the CentOS command line

Try this command:

find / -name file.look

Access denied for user 'root'@'localhost' while attempting to grant privileges. How do I grant privileges?

For those who still stumble upon this like I did, it's worth checking to make sure the attempted GRANT does not already exist:

SHOW GRANTS FOR username;

In my case, the error was not actually because there was a permission error, but because the GRANT already existed.

In PHP, how do you change the key of an array element?

You can write simple function that applies the callback to the keys of the given array. Similar to array_map

<?php
function array_map_keys(callable $callback, array $array) {
    return array_merge([], ...array_map(
        function ($key, $value) use ($callback) { return [$callback($key) => $value]; },
        array_keys($array),
        $array
    ));
}

$array = ['a' => 1, 'b' => 'test', 'c' => ['x' => 1, 'y' => 2]];
$newArray = array_map_keys(function($key) { return 'new' . ucfirst($key); }, $array);

echo json_encode($array); // {"a":1,"b":"test","c":{"x":1,"y":2}}
echo json_encode($newArray); // {"newA":1,"newB":"test","newC":{"x":1,"y":2}}

Here is a gist https://gist.github.com/vardius/650367e15abfb58bcd72ca47eff096ca#file-array_map_keys-php.

Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_151 contains a valid JDK installation

In my case, i had installed only the JRE so you could check to make sure you actually have a valid jdk. if not i advise you to uninstall whatever java is installed and download a correct jdk from here (the jdk comes with a jre so no need to download anything else) after set the environment variable and your done

Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.12:test (default-test) on project.

Check your test files. You must clear all test files error on your project and try Clean and build.

How to recover the deleted files using "rm -R" command in linux server?

Not possible with standard unix commands. You might have luck with a file recovery utility. Also, be aware, using rm changes the table of contents to mark those blocks as available to be overwritten, so simply using your computer right now risks those blocks being overwritten permanently. If it's critical data, you should turn off the computer before the file sectors gets overwritten. Good luck!

Some restore utility: http://www.ubuntugeek.com/recover-deleted-files-with-foremostscalpel-in-ubuntu.html

Forum where this was previously answered: http://webcache.googleusercontent.com/search?q=cache:m4hiPw-_GekJ:ubuntuforums.org/archive/index.php/t-1134955.html+&cd=1&hl=en&ct=clnk&gl=us

How to make a back-to-top button using CSS and HTML only?

HTML

<a name="gettop"></a>

<button id="btn"><a href="#gettop">Back to Top</a></button>

CSS

#btn {  
    position: fixed;
    bottom: 10px;
    float: right;
    right: 20.5%;
    left: 77.25%;
    max-width: 90px;
    width: 100%;
    font-size: 12px;
    border-color: rgba(5, 82, 248);
    background-color: rgb(5, 82, 248);
    padding: .5px;
    border-radius: 4px;
    font-family: Georgia, 'Times New Roman', Times, serif;
}

On Hover Color Change

#btn:hover {
    background-color: #fafafa;
}

How to set layout_gravity programmatically?

Modify the existing layout params and set layout params again

//Get the current layout params and update the Gravity
(iv.layoutParams as FrameLayout.LayoutParams).gravity = Gravity.START
//Set layout params again (this updates the view)
iv.layoutParams = layoutParams

Retrieve CPU usage and memory usage of a single process on Linux?

ps command (should not use):

top command (should use):

Use top to get CPU usage in real time(current short interval):

top -b -n 2 -d 0.2 -p 6962 | tail -1 | awk '{print $9}'

will echo like: 78.6

How do I display the value of a Django form field in a template?

You can do this from the template with something like this:

{% if form.instance.some_field %}
      {{form.instance.some_field}}
{% else %}
      {{form.data.some_field}}
{% endif %}

This will display the instance value (if the form is created with an instance, you can use initial instead if you like), or else display the POST data such as when a validation error occurs.

How to describe table in SQL Server 2008?

As a variation of Bridge's answer (I don't yet have enough rep to comment, and didn't feel right about editing that answer), here is a version that works better for me.

SELECT column_name AS [Name],
   IS_NULLABLE AS [Null?],
   DATA_TYPE + CASE
                 WHEN CHARACTER_MAXIMUM_LENGTH IS NULL THEN ''
                 WHEN CHARACTER_MAXIMUM_LENGTH > 99999 THEN ''
                 ELSE '(' + Cast(CHARACTER_MAXIMUM_LENGTH AS VARCHAR(5)) + ')' 
               END AS [Type]
FROM   INFORMATION_SCHEMA.Columns
WHERE  table_name = 'table_name'

Notable changes:

  • Works for types without length. For an int column, I was seeing NULL for the type because the length was null and it wiped out the whole Type column. So don't print any length component (or parens).
  • Change the check for CAST length of -1 to check actual length. I was getting a syntax error because the case resulted in '*' rather than -1. Seems to make more sense to perform an arithmetic check rather than an overflow from the CAST.
  • Don't print length when very long (arbitrarily > 5 digits).

Hashmap does not work with int, char

Generics can't use primitive types in the form of keywords.

Use

public HashMap<Character, Integer> buildMap(String letters)
{
    HashMap<Character, Integer> checkSum = new HashMap<Character, Integer>();

    for ( int i = 0; i < letters.length(); ++i )
    {
        checkSum.put(letters.charAt(i), primes[i]);
    }

    return checkSum;
}

Updated: With Java 7 and later, you can use the diamond operator.

HashMap<Character, Integer> checkSum = new HashMap<>();

Delayed rendering of React components

We can solve this using Hooks:

First we'll need a timeout hook for the delay.

This one is inspired by Dan Abramov's useInterval hook (see Dan's blog post for an in depth explanation), the differences being:

  1. we use we setTimeout not setInterval
  2. we return a reset function allowing us to restart the timer at any time

_x000D_
_x000D_
import { useEffect, useRef, useCallback } from 'react';_x000D_
_x000D_
const useTimeout = (callback, delay) => {_x000D_
  // save id in a ref_x000D_
  const timeoutId = useRef('');_x000D_
_x000D_
  // save callback as a ref so we can update the timeout callback without resetting the clock_x000D_
  const savedCallback = useRef();_x000D_
  useEffect(_x000D_
    () => {_x000D_
      savedCallback.current = callback;_x000D_
    },_x000D_
    [callback],_x000D_
  );_x000D_
_x000D_
  // clear the timeout and start a new one, updating the timeoutId ref_x000D_
  const reset = useCallback(_x000D_
    () => {_x000D_
      clearTimeout(timeoutId.current);_x000D_
_x000D_
      const id = setTimeout(savedCallback.current, delay);_x000D_
      timeoutId.current = id;_x000D_
    },_x000D_
    [delay],_x000D_
  );_x000D_
_x000D_
  useEffect(_x000D_
    () => {_x000D_
      if (delay !== null) {_x000D_
        reset();_x000D_
_x000D_
        return () => clearTimeout(timeoutId.current);_x000D_
      }_x000D_
    },_x000D_
    [delay, reset],_x000D_
  );_x000D_
_x000D_
  return { reset };_x000D_
};
_x000D_
_x000D_
_x000D_

and now we need a hook which will capture previous children and use our useTimeout hook to swap in the new children after a delay

_x000D_
_x000D_
import { useState, useEffect } from 'react';_x000D_
_x000D_
const useDelayNextChildren = (children, delay) => {_x000D_
  const [finalChildren, setFinalChildren] = useState(children);_x000D_
_x000D_
  const { reset } = useTimeout(() => {_x000D_
    setFinalChildren(children);_x000D_
  }, delay);_x000D_
_x000D_
  useEffect(_x000D_
    () => {_x000D_
      reset();_x000D_
    },_x000D_
    [reset, children],_x000D_
  );_x000D_
_x000D_
  return finalChildren || children || null;_x000D_
};
_x000D_
_x000D_
_x000D_

Note that the useTimeout callback will always have the latest children, so even if we attempt to render multiple different new children within the delay time, we'll always get the latest children once the timeout finally completes.

Now in your case, we want to also delay the initial render, so we make this change:

_x000D_
_x000D_
const useDelayNextChildren = (children, delay) => {_x000D_
  const [finalChildren, setFinalChildren] = useState(null); // initial state set to null_x000D_
_x000D_
  // ... stays the same_x000D_
_x000D_
  return finalChildren || null;  // remove children from return_x000D_
};
_x000D_
_x000D_
_x000D_

and using the above hook, your entire child component becomes

_x000D_
_x000D_
import React, { memo } from 'react';_x000D_
import { useDelayNextChildren } from 'hooks';_x000D_
_x000D_
const Child = ({ delay }) => useDelayNextChildren(_x000D_
  <div>_x000D_
    ... Child JSX goes here_x000D_
    ... etc_x000D_
  </div>_x000D_
  , delay_x000D_
);_x000D_
_x000D_
export default memo(Child);
_x000D_
_x000D_
_x000D_

or if you prefer: ( dont say i havent given you enough code ;) )

_x000D_
_x000D_
const Child = ({ delay }) => {_x000D_
  const render = <div>... Child JSX goes here ... etc</div>;_x000D_
_x000D_
  return useDelayNextChildren(render, delay);_x000D_
};
_x000D_
_x000D_
_x000D_

which will work exactly the same in the Parent render function as in the accepted answer

...

except the delay will be the same on every subsequent render too,

AND we used hooks, so that stateful logic is reusable across any component

...

...

use hooks. :D

Choosing a file in Python with simple Dialog

How about using tkinter?

from Tkinter import Tk     # from tkinter import Tk for Python 3.x
from tkinter.filedialog import askopenfilename

Tk().withdraw() # we don't want a full GUI, so keep the root window from appearing
filename = askopenfilename() # show an "Open" dialog box and return the path to the selected file
print(filename)

Done!

Convert string to decimal number with 2 decimal places in Java

This line is your problem:

litersOfPetrol = Float.parseFloat(df.format(litersOfPetrol));

There you formatted your float to string as you wanted, but but then that string got transformed again to a float, and then what you printed in stdout was your float that got a standard formatting. Take a look at this code

import java.text.DecimalFormat;

String stringLitersOfPetrol = "123.00";
System.out.println("string liters of petrol putting in preferences is "+stringLitersOfPetrol);
Float litersOfPetrol=Float.parseFloat(stringLitersOfPetrol);
DecimalFormat df = new DecimalFormat("0.00");
df.setMaximumFractionDigits(2);
stringLitersOfPetrol = df.format(litersOfPetrol);
System.out.println("liters of petrol before putting in editor : "+stringLitersOfPetrol);

And by the way, when you want to use decimals, forget the existence of double and float as others suggested and just use BigDecimal object, it will save you a lot of headache.

IntelliJ IDEA "The selected directory is not a valid home for JDK"

I had the same issue. But I figured it out by choosing this path:

First at all, you need to select the C:\ folder. Then, you select Program Files. After it, you select java, and finally the jdk you downloaded. In my case, I downloaded the JDK1.8.0_60 version.

To resume the path:

C:\Program Files\java\jdk1.8.0_60

After you are done with it, you can click on the button next. Then you select the create project from templates. This will create a java application with a main() method. After it, you click next to create the name of you project.

I hope this helps you.

Logger slf4j advantages of formatting with {} instead of string concatenation

I think from the author's point of view, the main reason is to reduce the overhead for string concatenation.I just read the logger's documentation, you could find following words:

/**
* <p>This form avoids superfluous string concatenation when the logger
* is disabled for the DEBUG level. However, this variant incurs the hidden
* (and relatively small) cost of creating an <code>Object[]</code> before 
  invoking the method,
* even if this logger is disabled for DEBUG. The variants taking
* {@link #debug(String, Object) one} and {@link #debug(String, Object, Object) two}
* arguments exist solely in order to avoid this hidden cost.</p>
*/
*
 * @param format    the format string
 * @param arguments a list of 3 or more arguments
 */
public void debug(String format, Object... arguments);

Saving an Excel sheet in a current directory with VBA

If the Path is omitted the file will be saved automaticaly in the current directory. Try something like this:

ActiveWorkbook.SaveAs "Filename.xslx"

Finding elements not in a list

Your code is a no-op. By the definition of the loop, "item" has to be in Z. A "For ... in" loop in Python means "Loop though the list called 'z', each time you loop, give me the next item in the list, and call it 'item'"

http://docs.python.org/tutorial/controlflow.html#for-statements

I think your confusion arises from the fact that you're using the variable name "item" twice, to mean two different things.

How to use java.String.format in Scala?

Instead of looking at the source code, you should read the javadoc String.format() and Formatter syntax.

You specify the format of the value after the %. For instance for decimal integer it is d, and for String it is s:

String aString = "world";
int aInt = 20;
String.format("Hello, %s on line %d",  aString, aInt );

Output:

Hello, world on line 20

To do what you tried (use an argument index), you use: *n*$,

String.format("Line:%2$d. Value:%1$s. Result: Hello %1$s at line %2$d", aString, aInt );

Output:

Line:20. Value:world. Result: Hello world at line 20

What is the perfect counterpart in Python for "while not EOF"

Loop over the file to read lines:

with open('somefile') as openfileobject:
    for line in openfileobject:
        do_something()

File objects are iterable and yield lines until EOF. Using the file object as an iterable uses a buffer to ensure performant reads.

You can do the same with the stdin (no need to use raw_input():

import sys

for line in sys.stdin:
    do_something()

To complete the picture, binary reads can be done with:

from functools import partial

with open('somefile', 'rb') as openfileobject:
    for chunk in iter(partial(openfileobject.read, 1024), b''):
        do_something()

where chunk will contain up to 1024 bytes at a time from the file, and iteration stops when openfileobject.read(1024) starts returning empty byte strings.

Opening port 80 EC2 Amazon web services

This is actually really easy:

  • Go to the "Network & Security" -> Security Group settings in the left hand navigation
  • Find the Security Group that your instance is apart of
  • Click on Inbound Rules
  • Use the drop down and add HTTP (port 80)
  • Click Apply and enjoy

Python Pandas counting and summing specific conditions

You can first make a conditional selection, and sum up the results of the selection using the sum function.

>> df = pd.DataFrame({'a': [1, 2, 3]})
>> df[df.a > 1].sum()   
a    5
dtype: int64

Having more than one condition:

>> df[(df.a > 1) & (df.a < 3)].sum()
a    2
dtype: int64

How do you get the current page number of a ViewPager for Android?

in the latest packages you can also use

vp.getCurrentItem()

or

vp is the viewPager ,

pageListener = new PageListener();
vp.setOnPageChangeListener(pageListener);

you have to put a page change listener for your viewPager. There is no method on viewPager to get the current page.

private int currentPage;

    private static class PageListener extends SimpleOnPageChangeListener{
            public void onPageSelected(int position) {
                Log.i(TAG, "page selected " + position);
                   currentPage = position;
        }
    }

When do I use path params vs. query params in a RESTful API?

In a REST API, you shouldn't be overly concerned by predictable URI's. The very suggestion of URI predictability alludes to a misunderstanding of RESTful architecture. It assumes that a client should be constructing URIs themselves, which they really shouldn't have to.

However, I assume that you are not creating a true REST API, but a 'REST inspired' API (such as the Google Drive one). In these cases the rule of thumb is 'path params = resource identification' and 'query params = resource sorting'. So, the question becomes, can you uniquely identify your resource WITHOUT status / region? If yes, then perhaps its a query param. If no, then its a path param.

HTH.

Print DIV content by JQuery

You can follow these steps :

  1. wrap the div you want to print into another div.
  2. set the wrapper div display status to none in css.
  3. keep the div you want to print display status as block, anyway it will be hidden as its parent is hidden.
  4. simply call $('SelectorToPrint').printElement();

Add marker to Google Map on Click

Currently the method to add the listener to the map would be

map.addListener('click', function(e) {
    placeMarker(e.latLng, map);
});

And not

google.maps.event.addListener(map, 'click', function(e) {
    placeMarker(e.latLng, map);
});

Reference

Python Math - TypeError: 'NoneType' object is not subscriptable

lista = list.sort(lista)

This should be

lista.sort()

The .sort() method is in-place, and returns None. If you want something not in-place, which returns a value, you could use

sorted_list = sorted(lista)

Aside #1: please don't call your lists list. That clobbers the builtin list type.

Aside #2: I'm not sure what this line is meant to do:

print str("value 1a")+str(" + ")+str("value 2")+str(" = ")+str("value 3a ")+str("value 4")+str("\n")

is it simply

print "value 1a + value 2 = value 3a value 4"

? In other words, I don't know why you're calling str on things which are already str.

Aside #3: sometimes you use print("something") (Python 3 syntax) and sometimes you use print "something" (Python 2). The latter would give you a SyntaxError in py3, so you must be running 2.*, in which case you probably don't want to get in the habit or you'll wind up printing tuples, with extra parentheses. I admit that it'll work well enough here, because if there's only one element in the parentheses it's not interpreted as a tuple, but it looks strange to the pythonic eye..


The exception TypeError: 'NoneType' object is not subscriptable happens because the value of lista is actually None. You can reproduce TypeError that you get in your code if you try this at the Python command line:

None[0]

The reason that lista gets set to None is because the return value of list.sort() is None... it does not return a sorted copy of the original list. Instead, as the documentation points out, the list gets sorted in-place instead of a copy being made (this is for efficiency reasons).

If you do not want to alter the original version you can use

other_list = sorted(lista)

Why is the parent div height zero when it has floated children

Content that is floating does not influence the height of its container. The element contains no content that isn't floating (so nothing stops the height of the container being 0, as if it were empty).

Setting overflow: hidden on the container will avoid that by establishing a new block formatting context. See methods for containing floats for other techniques and containing floats for an explanation about why CSS was designed this way.

if...else within JSP or JSTL

If you just want to output different text, a more concise example would be

${condition ? "some text when true" : "some text when false"}

It is way shorter than c:choose.

Maximum on http header values?

If you are going to use any DDOS provider like Akamai, they have a maximum limitation of 8k in the response header size. So essentially try to limit your response header size below 8k.

How to get text of an element in Selenium WebDriver, without including child element text?

Unfortunately, Selenium was only built to work with Elements, not Text nodes.

If you try to use a function like get_element_by_xpath to target the text nodes, Selenium will throw an InvalidSelectorException.

One workaround is to grab the relevant HTML with Selenium and then use an HTML parsing library like BeautifulSoup that can handle text nodes more elegantly.

import bs4
from bs4 import BeautifulSoup

inner_html = driver.find_elements_by_css_selector('#a')[0].get_attribute("innerHTML")
inner_soup = BeautifulSoup(inner_html, 'html.parser')

outer_html = driver.find_elements_by_css_selector('#a')[0].get_attribute("outerHTML")
outer_soup = BeautifulSoup(outer_html, 'html.parser')

From there, there are several ways to search for the Text content. You'll have to experiment to see what works best for your use case.

Here's a simple one-liner that may be sufficient:

inner_soup.find(text=True)

If that doesn't work, then you can loop through the element's child nodes with .contents() and check their object type.

BeautifulSoup has four types of elements, and the one that you'll be interested in is the NavigableString type, which is produced by Text nodes. By contrast, Elements will have a type of Tag.

contents = inner_soup.contents

for bs4_object in contents:

    if (type(bs4_object) == bs4.Tag):
        print("This object is an Element.")

    elif (type(bs4_object) == bs4.NavigableString):
        print("This object is a Text node.")

Note that BeautifulSoup doesn't support Xpath expressions. If you need those, then you can use some of the workarounds in this thread.

Recommendations of Python REST (web services) framework?

I strongly recommend TurboGears or Bottle:

TurboGears:

  • less verbose than django
  • more flexible, less HTML-oriented
  • but: less famous

Bottle:

  • very fast
  • very easy to learn
  • but: minimalistic and not mature

Converting a char to ASCII?

A char is an integral type. When you write

char ch = 'A';

you're setting the value of ch to whatever number your compiler uses to represent the character 'A'. That's usually the ASCII code for 'A' these days, but that's not required. You're almost certainly using a system that uses ASCII.

Like any numeric type, you can initialize it with an ordinary number:

char ch = 13;

If you want do do arithmetic on a char value, just do it: ch = ch + 1; etc.

However, in order to display the value you have to get around the assumption in the iostreams library that you want to display char values as characters rather than numbers. There are a couple of ways to do that.

std::cout << +ch << '\n';
std::cout << int(ch) << '\n'

How do I rotate the Android emulator display?

I have checked on Windows: Ctrl + F11 and Ctrl + F12 both are working to change the orientation of the Android simulator.

For other shortcut keys:

In the Eclipse toolbar go to "Help-->key Assist.. "

You can also use Ctrl + Shift + L here, so many shortcut keys of Eclipse are given.

Batch files: How to read a file?

Under NT-style cmd.exe, you can loop through the lines of a text file with

FOR /F %i IN (file.txt) DO @echo %i

Type "help for" on the command prompt for more information. (don't know if that works in whatever "DOS" you are using)

How to set limits for axes in ggplot2 R plots?

Quick note: if you're also using coord_flip() to flip the x and the y axis, you won't be able to set range limits using coord_cartesian() because those two functions are exclusive (see here).

Fortunately, this is an easy fix; set your limits within coord_flip() like so:

p + coord_flip(ylim = c(3,5), xlim = c(100, 400))

This just alters the visible range (i.e. doesn't remove data points).

Unrecognized SSL message, plaintext connection? Exception

i solved my problem using port 25 and Following prop

mailSender.javaMailProperties.putAll([
                "mail.smtp.auth": "true",
                "mail.smtp.starttls.enable": "false",
                "mail.smtp.ssl.enable": "false",
                "mail.smtp.socketFactory.fallback": "true",
        ]);

Authenticated HTTP proxy with Java

Try this runner I wrote. It could be helpful.

import java.io.InputStream;
import java.lang.reflect.Method;
import java.net.Authenticator;
import java.net.PasswordAuthentication;
import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;

public class ProxyAuthHelper {

    public static void main(String[] args) throws Exception {
        String tmp = System.getProperty("http.proxyUser", System.getProperty("https.proxyUser"));
        if (tmp == null) {
            System.out.println("Proxy username: ");
            tmp = new Scanner(System.in).nextLine();
        }
        final String userName = tmp;

        tmp = System.getProperty("http.proxyPassword", System.getProperty("https.proxyPassword"));
        if (tmp == null) {
            System.out.println("Proxy password: ");
            tmp = new Scanner(System.in).nextLine();
        }
        final char[] password = tmp.toCharArray();

        Authenticator.setDefault(new Authenticator() {
            @Override
            protected PasswordAuthentication getPasswordAuthentication() {
                System.out.println("\n--------------\nProxy auth: " + userName);
                return new PasswordAuthentication (userName, password);
            }

         });

        Class<?> clazz = Class.forName(args[0]);
        Method method = clazz.getMethod("main", String[].class);
        String[] newArgs = new String[args.length - 1];
        System.arraycopy(args, 1, newArgs, 0, newArgs.length);
        method.invoke(null, new Object[]{newArgs});
    }

}

PHP function to get the subdomain of a URL

You can do this by first getting the domain name (e.g. sub.example.com => example.co.uk) and then use strstr to get the subdomains.

$testArray = array(
    'sub1.sub2.example.co.uk',
    'sub1.example.com',
    'example.com',
    'sub1.sub2.sub3.example.co.uk',
    'sub1.sub2.sub3.example.com',
    'sub1.sub2.example.com'
);

foreach($testArray as $k => $v)
{
    echo $k." => ".extract_subdomains($v)."\n";
}

function extract_domain($domain)
{
    if(preg_match("/(?P<domain>[a-z0-9][a-z0-9\-]{1,63}\.[a-z\.]{2,6})$/i", $domain, $matches))
    {
        return $matches['domain'];
    } else {
        return $domain;
    }
}

function extract_subdomains($domain)
{
    $subdomains = $domain;
    $domain = extract_domain($subdomains);

    $subdomains = rtrim(strstr($subdomains, $domain, true), '.');

    return $subdomains;
}

Outputs:

0 => sub1.sub2
1 => sub1
2 =>
3 => sub1.sub2.sub3
4 => sub1.sub2.sub3
5 => sub1.sub2

Get average color of image via Javascript

Figured I'd post a project I recently came across to get dominant color:

Color Thief

A script for grabbing the dominant color or a representative color palette from an image. Uses javascript and canvas.

The other solutions mentioning and suggesting dominant color never really answer the question in proper context ("in javascript"). Hopefully this project will help those who want to do just that.

Disable asp.net button after click to prevent double clicking

Check this link, the most simplest way and it does not disable the validations.

http://aspsnippets.com/Articles/Disable-Button-before-Page-PostBack-in-ASP.Net.aspx

If you have e.g.

  <form id="form1" runat="server">
      <asp:Button ID="Button1" runat="server" Text="Button1" OnClick="Button1_Clicked" />
  </form>

Then you can use

  <script type = "text/javascript">
  function DisableButton() {
      document.getElementById("<%=Button1.ClientID %>").disabled = true;
  }
  window.onbeforeunload = DisableButton;
  </script>

To disable the button if and after validation has succeeded, just as the page is doing a server postback.

Getting error in console : Failed to load resource: net::ERR_CONNECTION_RESET

I had a similar issue using Apache 2.4 and PHP 7.

My client sent a lot of requests when refreshing (hard reloading) my application page in the browser and every time some of the last requests resulted in this error in console:

GET http://example.com/api/v1/my/resource net::ERR_CONNECTION_RESET

It turned out that my client was reaching the maximum amount of threads that was allowed. The threads exceeding this configured ceiling are simply not handled by Apache at all resulting in the connection reset error response.

The amount of threads can be easily raised by setting the ThreadsPerChild value for the module in question.
The easiest way to make such change is to uncomment the Server-pool management config file conf/extra/httpd-mpm.conf and then editing the preset values in the file to desired values.

1) Uncomment the Server-pool management file

# Server-pool management (MPM specific)
Include conf/extra/httpd-mpm.conf

2) Open and edit the file conf/extra/httpd-mpm.conf and raise the amount of threads

In my case I had to change the threads for the mpm_winnt_module:

# raised the amount of threads for mpm_winnt_module to 250
<IfModule mpm_winnt_module>
    ThreadsPerChild        250
    MaxConnectionsPerChild   0
</IfModule>

A comprehensive explanation on these Server-pool management configuration settings can be found in this post on StackOverflow.

How do you connect to a MySQL database using Oracle SQL Developer?

Under Tools > Preferences > Databases there is a third party JDBC driver path that must be setup. Once the driver path is setup a separate 'MySQL' tab should appear on the New Connections dialog.

Note: This is the same jdbc connector that is available as a JAR download from the MySQL website.

m2e lifecycle-mapping not found

Maven is trying to download m2e's lifecycle-mapping artifact, which M2E uses to determine how to process plugins within Eclipse (adding source folders, etc.). For some reason this artifact cannot be downloaded. Do you have an internet connection? Can other artifacts be downloaded from repositories? Proxy settings?

For more details from Maven, try turning M2E debug output on (Settings/Maven/Debug Output checkbox) and it might give you more details as to why it cannot download from the repository.

Adding Http Headers to HttpClient

Create a HttpRequestMessage, set the Method to GET, set your headers and then use SendAsync instead of GetAsync.

var client = new HttpClient();
var request = new HttpRequestMessage() {
    RequestUri = new Uri("http://www.someURI.com"),
    Method = HttpMethod.Get,
};
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("text/plain"));
var task = client.SendAsync(request)
    .ContinueWith((taskwithmsg) =>
    {
        var response = taskwithmsg.Result;

        var jsonTask = response.Content.ReadAsAsync<JsonObject>();
        jsonTask.Wait();
        var jsonObject = jsonTask.Result;
    });
task.Wait();

PHP Accessing Parent Class Variable

echo $this->bb;

The variable is inherited and is not private, so it is a part of the current object.


Here is additional information in response to your request for more information about using parent:::

Use parent:: when you want add extra functionality to a method from the parent class. For example, imagine an Airplane class:

class Airplane {
    private $pilot;

    public function __construct( $pilot ) {
        $this->pilot = $pilot;
    }
}

Now suppose we want to create a new type of Airplane that also has a navigator. You can extend the __construct() method to add the new functionality, but still make use of the functionality offered by the parent:

class Bomber extends Airplane {
    private $navigator;

    public function __construct( $pilot, $navigator ) {
        $this->navigator = $navigator;

        parent::__construct( $pilot ); // Assigns $pilot to $this->pilot
    }
}

In this way, you can follow the DRY principle of development but still provide all of the functionality you desire.

Regex to Match Symbols: !$%^&*()_+|~-=`{}[]:";'<>?,./

Replace all latters from any language in 'A', and if you wish for example all digits to 0:

return str.replace(/[^\s!-@[-`{-~]/g, "A").replace(/\d/g, "0");

Can I run javascript before the whole page is loaded?

You can run javascript code at any time. AFAIK it is executed at the moment the browser reaches the <script> tag where it is in. But you cannot access elements that are not loaded yet.

So if you need access to elements, you should wait until the DOM is loaded (this does not mean the whole page is loaded, including images and stuff. It's only the structure of the document, which is loaded much earlier, so you usually won't notice a delay), using the DOMContentLoaded event or functions like $.ready in jQuery.

The type initializer for 'CrystalDecisions.CrystalReports.Engine.ReportDocument' threw an exception

The inner exception of bug says Could not load file or assembly 'log4net, Version=1.2.10.0, Culture=neutral, PublicKeyToken=692fbea5521e1304'

Changing the AppPool setting False for Enable 32-bit Application solved the issue

how to use substr() function in jquery?

Extract characters from a string:

var str = "Hello world!";
var res = str.substring(1,4);

The result of res will be:

ell

http://www.w3schools.com/jsref/jsref_substring.asp

$('.dep_buttons').mouseover(function(){
    $(this).text().substring(0,25);
    if($(this).text().length > 30) {
        $(this).stop().animate({height:"150px"},150);
    }
    $(".dep_buttons").mouseout(function(){
        $(this).stop().animate({height:"40px"},150);
    });
});

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

Most preferable answer by @BankZ

sp_help 'TableName'   

additionally for different schema

sp_help 'schemaName.TableName'   

Use multiple custom fonts using @font-face?

I use this method in my css file

@font-face {
  font-family: FontName1;
  src: url("fontname1.eot"); /* IE */
  src: local('FontName1'), url('fontname1.ttf') format('truetype'); /* others */
}
@font-face {
  font-family: FontName2;
  src: url("fontname1.eot"); /* IE */
  src: local('FontName2'), url('fontname2.ttf') format('truetype'); /* others */
}
@font-face {
  font-family: FontName3;
  src: url("fontname1.eot"); /* IE */
  src: local('FontName3'), url('fontname3.ttf') format('truetype'); /* others */
}

Spark difference between reduceByKey vs groupByKey vs aggregateByKey vs combineByKey

ReduceByKey reduceByKey(func, [numTasks])-

Data is combined so that at each partition there should be at least one value for each key. And then shuffle happens and it is sent over the network to some particular executor for some action such as reduce.

GroupByKey - groupByKey([numTasks])

It doesn't merge the values for the key but directly the shuffle process happens and here lot of data gets sent to each partition, almost same as the initial data.

And the merging of values for each key is done after the shuffle. Here lot of data stored on final worker node so resulting in out of memory issue.

AggregateByKey - aggregateByKey(zeroValue)(seqOp, combOp, [numTasks]) It is similar to reduceByKey but you can provide initial values when performing aggregation.

Use of reduceByKey

  • reduceByKey can be used when we run on large data set.

  • reduceByKey when the input and output value types are of same type over aggregateByKey

Moreover it recommended not to use groupByKey and prefer reduceByKey. For details you can refer here.

You can also refer this question to understand in more detail how reduceByKey and aggregateByKey.

How to remove specific element from an array using python

You don't need to iterate the array. Just:

>>> x = ['[email protected]', '[email protected]']
>>> x
['[email protected]', '[email protected]']
>>> x.remove('[email protected]')
>>> x
['[email protected]']

This will remove the first occurence that matches the string.

EDIT: After your edit, you still don't need to iterate over. Just do:

index = initial_list.index(item1)
del initial_list[index]
del other_list[index]

How to check if an integer is within a range of numbers in PHP?

function limit_range($num, $min, $max)
{
  // Now limit it
  return $num>$max?$max:$num<$min?$min:$num;
}

$min = 0;  // Minimum number can be
$max = 4;  // Maximum number can be
$num = 10;  // Your number
// Number returned is limited to be minimum 0 and maximum 4
echo limit_range($num, $min, $max); // return 4
$num = 2;
echo limit_range($num, $min, $max); // return 2
$num = -1;
echo limit_range($num, $min, $max); // return 0

How to go to each directory and execute a command?

you can use

find .

to search all files/dirs in the current directory recurive

Than you can pipe the output the xargs command like so

find . | xargs 'command here'

What are the safe characters for making URLs?

I had a similar problem. I wanted to have pretty URLs and reached the conclusion that I have to allow only letters, digits, - and _ in URLs.

That is fine, but then I wrote some nice regex and I realized that it recognizes all UTF-8 characters are not letters in .NET and was screwed. This appears to be a know problem for the .NET regex engine. So I got to this solution:

private static string GetTitleForUrlDisplay(string title)
{
    if (!string.IsNullOrEmpty(title))
    {
        return Regex.Replace(Regex.Replace(title, @"[^A-Za-z0-9_-]", new MatchEvaluator(CharacterTester)).Replace(' ', '-').TrimStart('-').TrimEnd('-'), "[-]+", "-").ToLower();
    }
    return string.Empty;
}


/// <summary>
/// All characters that do not match the patter, will get to this method, i.e. useful for Unicode characters, because
/// .NET implementation of regex do not handle Unicode characters. So we use char.IsLetterOrDigit() which works nicely and we
/// return what we approve and return - for everything else.
/// </summary>
/// <param name="m"></param>
/// <returns></returns>
private static string CharacterTester(Match m)
{
    string x = m.ToString();
    if (x.Length > 0 && char.IsLetterOrDigit(x[0]))
    {
        return x.ToLower();
    }
    else
    {
        return "-";
    }
}

How to make the window full screen with Javascript (stretching all over the screen)

Try screenfull.js. It's a nice cross-browser solution that should work for Opera browser as well.

Simple wrapper for cross-browser usage of the JavaScript Fullscreen API, which lets you bring the page or any element into fullscreen. Smoothens out the browser implementation differences, so you don't have to.

Demo.

What is the easiest way to get the current day of the week in Android?

If you want to define the date string in strings.xml. You can do like below.
Calendar.DAY_OF_WEEK return value from 1 -> 7 <=> Calendar.SUNDAY -> Calendar.SATURDAY

strings.xml

<string-array name="title_day_of_week">
    <item>?</item> <!-- sunday -->
    <item>?</item> <!-- monday -->
    <item>?</item>
    <item>?</item>
    <item>?</item>
    <item>?</item>
    <item>?</item> <!-- saturday -->
</string-array>

DateExtension.kt

fun String.getDayOfWeek(context: Context, format: String): String {
    val date = SimpleDateFormat(format, Locale.getDefault()).parse(this)
    return date?.getDayOfWeek(context) ?: "unknown"
}

fun Date.getDayOfWeek(context: Context): String {
    val c = Calendar.getInstance().apply { time = this@getDayOfWeek }
    return context.resources.getStringArray(R.array.title_day_of_week)[c[Calendar.DAY_OF_WEEK] - 1]
}

Using

// get current day
val currentDay = Date().getDayOfWeek(context)

// get specific day
val dayString = "2021-1-4"
val day = dayString.getDayOfWeek(context, "yyyy-MM-dd")

How to swap two variables in JavaScript

ES6 (Firefox and Chrome already support it (Destructuring Assignment Array Matching)):

_x000D_
_x000D_
let a = 5, b = 6;_x000D_
[a, b] = [b, a];_x000D_
console.log(`${a} ${b}`);
_x000D_
_x000D_
_x000D_

PHP removing a character in a string

I think that it's better to use simply str_replace, like the manual says:

If you don't need fancy replacing rules (like regular expressions), you should always use this function instead of ereg_replace() or preg_replace().

<?
$badUrl = "http://www.site.com/backend.php?/c=crud&m=index&t=care";
$goodUrl = str_replace('?/', '?', $badUrl);

How to set headers in http get request?

The Header field of the Request is public. You may do this :

req.Header.Set("name", "value")

CSS scrollbar style cross browser

jScrollPane is a good solution to cross browser scrollbars and degrades nicely.

How to use OKHTTP to make a post request?

OkHttp POST request with token in header

       RequestBody requestBody = new MultipartBody.Builder()
            .setType(MultipartBody.FORM)
            .addFormDataPart("search", "a")
            .addFormDataPart("model", "1")
            .addFormDataPart("in", "1")
            .addFormDataPart("id", "1")
            .build();
    OkHttpClient client = new OkHttpClient();
    okhttp3.Request request = new okhttp3.Request.Builder()
            .url("https://somedomain.com/api")
            .post(requestBody)
            .addHeader("token", "eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiIkMnkkMTAkZzZrLkwySlFCZlBmN1RTb3g3bmNpTzltcVwvemRVN2JtVC42SXN0SFZtbzZHNlFNSkZRWWRlIiwic3ViIjo0NSwiaWF0IjoxNTUwODk4NDc0LCJleHAiOjE1NTM0OTA0NzR9.tefIaPzefLftE7q0yKI8O87XXATwowEUk_XkAOOQzfw")
            .addHeader("cache-control", "no-cache")
            .addHeader("Postman-Token", "7e231ef9-5236-40d1-a28f-e5986f936877")
            .build();

    client.newCall(request).enqueue(new Callback() {
        @Override
        public void onFailure(Call call, IOException e) {
            e.printStackTrace();
        }

        @Override
        public void onResponse(Call call, okhttp3.Response response) throws IOException {
            if (response.isSuccessful()) {
                final String myResponse = response.body().string();

                MainActivity.this.runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        Log.d("response", myResponse);
                        progress.hide();
                    }
                });
            }
        }
    });

What does the clearfix class do in css?

clearfix is the same as overflow:hidden. Both clear floated children of the parent, but clearfix will not cut off the element which overflow to it's parent. It also works in IE8 & above.

There is no need to define "." in content & .clearfix. Just write like this:

.clr:after {
    clear: both;
    content: "";
    display: block;
}

HTML

<div class="parent clr"></div>

Read these links for more

http://css-tricks.com/snippets/css/clear-fix/,

What methods of ‘clearfix’ can I use?

Check if PHP session has already started

if (version_compare(PHP_VERSION, "5.4.0") >= 0) {
    $sess = session_status();
    if ($sess == PHP_SESSION_NONE) {
        session_start();
    }
} else {
    if (!$_SESSION) {
        session_start();
    }
}

Actually, it is now too late to explain it here anyway as its been solved. This was a .inc file of one of my projects where you configure a menu for a restaurant by selecting a dish and remove/add or change the order. The server I was working at did not had the actual version so I made it more flexible. It's up to the authors wish to use and try it out.

angular 2 how to return data from subscribe

I have used this way lots time ...

_x000D_
_x000D_
@Component({_x000D_
   selector: "data",_x000D_
   template: "<h1>{{ getData() }}</h1>"_x000D_
})_x000D_
_x000D_
export class DataComponent{_x000D_
    this.http.get(path).subscribe({_x000D_
       DataComponent.setSubscribeData(res);_x000D_
    })_x000D_
}_x000D_
_x000D_
_x000D_
static subscribeData:any;_x000D_
static setSubscribeData(data):any{_x000D_
    DataComponent.subscribeData=data;_x000D_
    return data;_x000D_
}
_x000D_
_x000D_
_x000D_

use static keyword and save your time... here either you can use static variable or directly return object you want.... hope it will help you.. happy coding...

How can I create an observable with a delay

It's little late to answer ... but just in case may be someone return to this question looking for an answer

'delay' is property(function) of an Observable

fakeObservable = Observable.create(obs => {
  obs.next([1, 2, 3]);
  obs.complete();
}).delay(3000);

This worked for me ...

How to terminate a Python script

While you should generally prefer sys.exit because it is more "friendly" to other code, all it actually does is raise an exception.

If you are sure that you need to exit a process immediately, and you might be inside of some exception handler which would catch SystemExit, there is another function - os._exit - which terminates immediately at the C level and does not perform any of the normal tear-down of the interpreter; for example, hooks registered with the "atexit" module are not executed.

Save base64 string as PDF at client side with JavaScript

_x000D_
_x000D_
dataURItoBlob(dataURI) {_x000D_
      const byteString = window.atob(dataURI);_x000D_
      const arrayBuffer = new ArrayBuffer(byteString.length);_x000D_
      const int8Array = new Uint8Array(arrayBuffer);_x000D_
      for (let i = 0; i < byteString.length; i++) {_x000D_
        int8Array[i] = byteString.charCodeAt(i);_x000D_
      }_x000D_
      const blob = new Blob([int8Array], { type: 'application/pdf'});_x000D_
      return blob;_x000D_
    }_x000D_
_x000D_
// data should be your response data in base64 format_x000D_
_x000D_
const blob = this.dataURItoBlob(data);_x000D_
const url = URL.createObjectURL(blob);_x000D_
_x000D_
// to open the PDF in a new window_x000D_
window.open(url, '_blank');
_x000D_
_x000D_
_x000D_

how to convert an RGB image to numpy array?

You can get numpy array of rgb image easily by using numpy and Image from PIL

import numpy as np
from PIL import Image
import matplotlib.pyplot as plt

im = Image.open('*image_name*') #These two lines
im_arr = np.array(im) #are all you need
plt.imshow(im_arr) #Just to verify that image array has been constructed properly

Tests not running in Test Explorer

Check what framework the tests are written against (e.g. nunit, xunit, VS test, etc.) and make sure you've got the correct test adapter/runner extension installed.

For me it was NUnit 3 Test Adapter that was missing and I confirmed the version number required by looking at the nunit.framework dependency version (select the .dll in the Dependencies tree in Solution Explorer and hit F4 to bring up the Properties window).

curl usage to get header

curl --head https://www.example.net

I was pointed to this by curl itself; when I issued the command with -X HEAD, it printed:

Warning: Setting custom HTTP method to HEAD with -X/--request may not work the 
Warning: way you want. Consider using -I/--head instead.

How to get the xml node value in string

The problem in your code is xml.LoadXml(filePath);

LoadXml method take parameter as xml data not the xml file path

Try this code

   string xmlFile = File.ReadAllText(@"D:\Work_Time_Calculator\10-07-2013.xml");
                XmlDocument xmldoc = new XmlDocument();
                xmldoc.LoadXml(xmlFile);
                XmlNodeList nodeList = xmldoc.GetElementsByTagName("Short_Fall");
                string Short_Fall=string.Empty;
                foreach (XmlNode node in nodeList)
                {
                    Short_Fall = node.InnerText;
                }

Edit

Seeing the last edit of your question i found the solution,

Just replace the below 2 lines

XmlNode node = xml.SelectSingleNode("/Data[@*]/Short_Fall");
string id = node["Short_Fall"].InnerText; // Exception occurs here ("Object reference not set to an instance of an object.")

with

string id = xml.SelectSingleNode("Data/Short_Fall").InnerText;

It should solve your problem or you can use the solution i provided earlier.

In reactJS, how to copy text to clipboard?

You should definitely consider using a package like @Shubham above is advising, but I created a working codepen based on what you described: http://codepen.io/dtschust/pen/WGwdVN?editors=1111 . It works in my browser in chrome, perhaps you can see if there's something I did there that you missed, or if there's some extended complexity in your application that prevents this from working.

// html
<html>
  <body>
    <div id="container">

    </div>
  </body>
</html>


// js
const Hello = React.createClass({
  copyToClipboard: () => {
    var textField = document.createElement('textarea')
    textField.innerText = 'foo bar baz'
    document.body.appendChild(textField)
    textField.select()
    document.execCommand('copy')
    textField.remove()
  },
  render: function () {
    return (
      <h1 onClick={this.copyToClipboard}>Click to copy some text</h1>
    )
  }
})

ReactDOM.render(
<Hello/>,
  document.getElementById('container'))

Logical operators ("and", "or") in DOS batch

An alternative is to look for a unix shell which does give you logical operators and a whole lot more. You can get a native win32 implementation of a Bourne shell here if you don't want to go the cygwin route. A native bash can be found here. I'm quite certain you could easily google other good alternatives such as zsh or tcsh.

K

@UniqueConstraint annotation in Java

You can use at class level with following syntax

@Entity
@Table(uniqueConstraints={@UniqueConstraint(columnNames={"username"})})
public class SomeEntity {
    @Column(name = "username")
    public String username;
}

Use ASP.NET MVC validation with jquery ajax?

Client Side

Using the jQuery.validate library should be pretty simple to set up.

Specify the following settings in your Web.config file:

<appSettings>
    <add key="ClientValidationEnabled" value="true"/> 
    <add key="UnobtrusiveJavaScriptEnabled" value="true"/> 
</appSettings>

When you build up your view, you would define things like this:

@Html.LabelFor(Model => Model.EditPostViewModel.Title, true)
@Html.TextBoxFor(Model => Model.EditPostViewModel.Title, 
                                new { @class = "tb1", @Style = "width:400px;" })
@Html.ValidationMessageFor(Model => Model.EditPostViewModel.Title)

NOTE: These need to be defined within a form element

Then you would need to include the following libraries:

<script src='@Url.Content("~/Scripts/jquery.validate.js")' type='text/javascript'></script>
<script src='@Url.Content("~/Scripts/jquery.validate.unobtrusive.js")' type='text/javascript'></script>

This should be able to set you up for client side validation

Resources

Server Side

NOTE: This is only for additional server side validation on top of jQuery.validation library

Perhaps something like this could help:

[ValidateAjax]
public JsonResult Edit(EditPostViewModel data)
{
    //Save data
    return Json(new { Success = true } );
}

Where ValidateAjax is an attribute defined as:

public class ValidateAjaxAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        if (!filterContext.HttpContext.Request.IsAjaxRequest())
            return;

        var modelState = filterContext.Controller.ViewData.ModelState;
        if (!modelState.IsValid)
        {
            var errorModel = 
                    from x in modelState.Keys
                    where modelState[x].Errors.Count > 0
                    select new
                           {
                               key = x,
                               errors = modelState[x].Errors.
                                                      Select(y => y.ErrorMessage).
                                                      ToArray()
                           };
            filterContext.Result = new JsonResult()
                                       {
                                           Data = errorModel
                                       };
            filterContext.HttpContext.Response.StatusCode = 
                                                  (int) HttpStatusCode.BadRequest;
        }
    }
}

What this does is return a JSON object specifying all of your model errors.

Example response would be

[{
    "key":"Name",
    "errors":["The Name field is required."]
},
{
    "key":"Description",
    "errors":["The Description field is required."]
}]

This would be returned to your error handling callback of the $.ajax call

You can loop through the returned data to set the error messages as needed based on the Keys returned (I think something like $('input[name="' + err.key + '"]') would find your input element

Getting Chrome to accept self-signed localhost certificate

When clicking the little crossed out lock icon next to the URL, you'll get a box looking like this:

enter image description here

After clicking the Certificate information link, you'll see the following dialog:

enter image description here

It tells you which certificate store is the correct one, it's the Trusted Root Certification Authorities store.

You can either use one of the methods outlined in the other answers to add the certificate to that store or use:

certutil -addstore -user "ROOT" cert.pem
  • ROOT is the internal name of the certificate store mentioned earlier.
  • cert.pem is the name of your self-signed certificate.

SVN 405 Method Not Allowed

I got this error because I replaced URL address with new one ending up with "/". I mean record in wc.db database in .svn folder in REPOSITORY table.

When I removed sign: "/" then the error went away.

Make div fill remaining space along the main axis in flexbox

Basically I was trying to get my code to have a middle section on a 'row' to auto-adjust to the content on both sides (in my case, a dotted line separator). Like @Michael_B suggested, the key is using display:flex on the row container and at least making sure your middle container on the row has a flex-grow value of at least 1 higher than the outer containers (if outer containers don't have any flex-grow properties applied, middle container only needs 1 for flex-grow).

Here's a pic of what I was trying to do and sample code for how I solved it.

enter image description here

_x000D_
_x000D_
.row {
  background: lightgray;
  height: 30px;
  width: 100%;
  display: flex;
  align-items:flex-end;
  margin-top:5px;
}
.left {
  background:lightblue;
}
.separator{
  flex-grow:1;
  border-bottom:dotted 2px black;
}
.right {
  background:coral;
}
_x000D_
<div class="row">
  <div class="left">Left</div>
  <div class="separator"></div>
  <div class="right">Right With Text</div>
</div>
<div class="row">
  <div class="left">Left With More Text</div>
  <div class="separator"></div>
  <div class="right">Right</div>
</div>
<div class="row">
  <div class="left">Left With Text</div>
  <div class="separator"></div>
  <div class="right">Right With More Text</div>
</div>
_x000D_
_x000D_
_x000D_

ORA-00972 identifier is too long alias column name

The error is also caused by quirky handling of quotes and single qutoes. To include single quotes inside the query, use doubled single quotes.

This won't work

select dbms_xmlgen.getxml("Select ....") XML from dual;

or this either

select dbms_xmlgen.getxml('Select .. where something='red'..') XML from dual;

but this DOES work

select dbms_xmlgen.getxml('Select .. where something=''red''..') XML from dual;

Build a basic Python iterator

Include the following code in your class code.

 def __iter__(self):
        for x in self.iterable:
            yield x

Make sure that you replace self.iterablewith the iterable which you iterate through.

Here's an example code

class someClass:
    def __init__(self,list):
        self.list = list
    def __iter__(self):
        for x in self.list:
            yield x


var = someClass([1,2,3,4,5])
for num in var: 
    print(num) 

Output

1
2
3
4
5

Note: Since strings are also iterable, they can also be used as an argument for the class

foo = someClass("Python")
for x in foo:
    print(x)

Output

P
y
t
h
o
n

How to convert a PIL Image into a numpy array?

You're not saying how exactly putdata() is not behaving. I'm assuming you're doing

>>> pic.putdata(a)
Traceback (most recent call last):
  File "...blablabla.../PIL/Image.py", line 1185, in putdata
    self.im.putdata(data, scale, offset)
SystemError: new style getargs format but argument is not a tuple

This is because putdata expects a sequence of tuples and you're giving it a numpy array. This

>>> data = list(tuple(pixel) for pixel in pix)
>>> pic.putdata(data)

will work but it is very slow.

As of PIL 1.1.6, the "proper" way to convert between images and numpy arrays is simply

>>> pix = numpy.array(pic)

although the resulting array is in a different format than yours (3-d array or rows/columns/rgb in this case).

Then, after you make your changes to the array, you should be able to do either pic.putdata(pix) or create a new image with Image.fromarray(pix).

How to remove class from all elements jquery

You need to select the li tags contained within the .edgetoedge class. .edgetoedge only matches the one ul tag:

$(".edgetoedge li").removeClass("highlight");

Boolean vs boolean in Java

One observation: (though this can be thought of side effect)

boolean being a primitive can either say yes or no.

Boolean is an object (it can refer to either yes or no or 'don't know' i.e. null)

How to install easy_install in Python 2.7.1 on Windows 7

I know this isn't a direct answer to your question but it does offer one solution to your problem. Python 2.7.9 includes PIP and SetupTools, if you update to this version you will have one solution to your problem.

How to use RANK() in SQL Server

Change:

RANK() OVER (PARTITION BY ContenderNum ORDER BY totals ASC) AS xRank

to:

RANK() OVER (ORDER BY totals DESC) AS xRank

Have a look at this example:

SQL Fiddle DEMO

You might also want to have a look at the difference between RANK (Transact-SQL) and DENSE_RANK (Transact-SQL):

RANK (Transact-SQL)

If two or more rows tie for a rank, each tied rows receives the same rank. For example, if the two top salespeople have the same SalesYTD value, they are both ranked one. The salesperson with the next highest SalesYTD is ranked number three, because there are two rows that are ranked higher. Therefore, the RANK function does not always return consecutive integers.

DENSE_RANK (Transact-SQL)

Returns the rank of rows within the partition of a result set, without any gaps in the ranking. The rank of a row is one plus the number of distinct ranks that come before the row in question.

LINQ orderby on date field in descending order

I don't believe that Distinct() is guaranteed to maintain the order of the set.

Try pulling out an anonymous type first and distinct/sort on that before you convert to string:

var ud = env.Select(d => new 
                         {
                             d.ReportDate.Year,
                             d.ReportDate.Month,
                             FormattedDate = d.ReportDate.ToString("yyyy-MMM")
                         })
            .Distinct()
            .OrderByDescending(d => d.Year)
            .ThenByDescending(d => d.Month)
            .Select(d => d.FormattedDate);

Synchronous Requests in Node.js

The short answer is: don't. (...) You really can't. And that's a good thing

I'd like to set the record straight regarding this:

NodeJS does support Synchronous Requests. It wasn't designed to support them out of the box, but there are a few workarounds if you are keen enough, here is an example:

var request = require('sync-request'),
    res1, res2, ucomp, vcomp;

try {
    res1 = request('GET', base + u_ext);
    res2 = request('GET', base + v_ext);
    ucomp = res1.split('\n')[1].split(', ')[1];
    vcomp = res2.split('\n')[1].split(', ')[1];
    doSomething(ucomp, vcomp);

} catch (e) {}

When you pop the hood open on the 'sync-request' library you can see that this runs a synchronous child process in the background. And as is explained in the sync-request README it should be used very judiciously. This approach locks the main thread, and that is bad for performance.

However, in some cases there is little or no advantage to be gained by writing an asynchronous solution (compared to the certain harm you are doing by writing code that is harder to read).

This is the default assumption held by many of the HTTP request libraries in other languages (Python, Java, C# etc), and that philosophy can also be carried to JavaScript. A language is a tool for solving problems after all, and sometimes you may not want to use callbacks if the benefits outweigh the disadvantages.

For JavaScript purists this may rankle of heresy, but I'm a pragmatist so I can clearly see that the simplicity of using synchronous requests helps if you find yourself in some of the following scenarios:

  1. Test Automation (tests are usually synchronous by nature).

  2. Quick API mash-ups (ie hackathon, proof of concept works etc).

  3. Simple examples to help beginners (before and after).

Be warned that the code above should not be used for production. If you are going to run a proper API then use callbacks, use promises, use async/await, or whatever, but avoid synchronous code unless you want to incur a significant cost for wasted CPU time on your server.

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)

I know this an old Question but i feel this might help someone. I was recently faced with the same problem but in my case, i remember my password quite alright but it kept on giving me the same error. I tried so many solutions but still none helped then i tried this

mysql -u root -p 

after which it asks you for a pass word like this

Enter password: 

and then i typed in the password i used. That's all

Exporting results of a Mysql query to excel?

This is an old question, but it's still one of the first results on Google. The fastest way to do this is to link MySQL directly to Excel using ODBC queries or MySQL For Excel. The latter was mentioned in a comment to the OP, but I felt it really deserved its own answer because exporting to CSV is not the most efficient way to achieve this.

ODBC Queries - This is a little bit more complicated to setup, but it's a lot more flexible. For example, the MySQL For Excel add-in doesn't allow you to use WHERE clauses in the query expressions. The flexibility of this method also allows you to use the data in more complex ways.

MySQL For Excel - Use this add-in if you don't need to do anything complex with the query or if you need to get something accomplished quickly and easily. You can make views in your database to workaround some of the query limitations.

How to count certain elements in array?

2017: If someone is still interested in the question, my solution is the following:

_x000D_
_x000D_
const arrayToCount = [1, 2, 3, 5, 2, 8, 9, 2];_x000D_
const result = arrayToCount.filter(i => i === 2).length;_x000D_
console.log('number of the found elements: ' + result);
_x000D_
_x000D_
_x000D_

What causes imported Maven project in Eclipse to use Java 1.5 instead of Java 1.6 by default and how can I ensure it doesn't?

In case anyone's wondering why Eclipse still puts a J2SE-1.5 library on the Java Build Path in a Maven project even if a Java version >= 9 is specified by the maven.compiler.release property (as of October 2020, that is Eclipse version 2020-09 including Maven version 3.6.3): Maven by default uses version 3.1 of the Maven compiler plugin, while the release property has been introduced only in version 3.6.

So don't forget to include a current version of the Maven compiler plugin in your pom.xml when using the release property:

<properties>
    <maven.compiler.release>15</maven.compiler.release>
</properties>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.1</version>
        </plugin>
    </plugins>
</build>

Or alternatively but possibly less prominent, specify the Java version directly in the plugin configuration:

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.1</version>
            <configuration>
                <release>15</release>
            </configuration>
        </plugin>
    </plugins>
</build>

This picks up Line's comment on the accepted answer which, had I seen it earlier, would have saved me another hour of searching.

Make Div Draggable using CSS

This is the best you can do without JavaScript:

_x000D_
_x000D_
[draggable=true] {_x000D_
  cursor: move;_x000D_
}_x000D_
_x000D_
.resizable {_x000D_
  overflow: scroll;_x000D_
  resize: both;_x000D_
  max-width: 300px;_x000D_
  max-height: 460px;_x000D_
  border: 1px solid black;_x000D_
  min-width: 50px;_x000D_
  min-height: 50px;_x000D_
  background-color: skyblue;_x000D_
}
_x000D_
<div draggable="true" class="resizable"></div>
_x000D_
_x000D_
_x000D_

Demo

Prevent form redirect OR refresh on submit?

In the opening tag of your form, set an action attribute like so:

<form id="contactForm" action="#">

MySQL query finding values in a comma separated string

select * from shirts where find_in_set('1',colors) <> 0

Works for me

Convert number to varchar in SQL with formatting

Here's an alternative following the last answer

declare @t tinyint,@v tinyint
set @t=23
set @v=232
Select replace(str(@t,4),' ','0'),replace(str(@t,5),' ','0')

This will work on any number and by varying the length of the str() function you can stipulate how many leading zeros you require. Provided of course that your string length is always >= maximum number of digits your number type can hold.

How do I run a simple bit of code in a new thread?

// following declaration of delegate ,,,
public delegate long GetEnergyUsageDelegate(DateTime lastRunTime, 
                                            DateTime procDateTime);

// following inside of some client method
GetEnergyUsageDelegate nrgDel = GetEnergyUsage;
IAsyncResult aR = nrgDel.BeginInvoke(lastRunTime, procDT, null, null);
while (!aR.IsCompleted) Thread.Sleep(500);
int usageCnt = nrgDel.EndInvoke(aR);

Charles your code(above) is not correct. You do not need to spin wait for completion. EndInvoke will block until the WaitHandle is signaled.

If you want to block until completion you simply need to

nrgDel.EndInvoke(nrgDel.BeginInvoke(lastRuntime,procDT,null,null));

or alternatively

ar.AsyncWaitHandle.WaitOne();

But what is the point of issuing anyc calls if you block? You might as well just use a synchronous call. A better bet would be to not block and pass in a lambda for cleanup:

nrgDel.BeginInvoke(lastRuntime,procDT,(ar)=> {ar.EndInvoke(ar);},null);

One thing to keep in mind is that you must call EndInvoke. A lot of people forget this and end up leaking the WaitHandle as most async implementations release the waithandle in EndInvoke.

Force Internet Explorer to use a specific Java Runtime Environment install?

Use the deployment Toolkit's deployJava.js (though this ensures a minimum version, rather than a specific version)

Restore a postgres backup file using the command line?

1.open the terminal.

2.backup your database with following command

your postgres bin - /opt/PostgreSQL/9.1/bin/

your source database server - 192.168.1.111

your backup file location and name - /home/dinesh/db/mydb.backup

your source db name - mydatabase

/opt/PostgreSQL/9.1/bin/pg_dump --host '192.168.1.111' --port 5432 --username "postgres" --no-password --format custom --blobs --file "/home/dinesh/db/mydb.backup" "mydatabase"

3.restore mydb.backup file into destination.

your destination server - localhost

your destination database name - mydatabase

create database for restore the backup.

/opt/PostgreSQL/9.1/bin/psql -h 'localhost' -p 5432 -U postgres -c "CREATE DATABASE mydatabase"

restore the backup.

/opt/PostgreSQL/9.1/bin/pg_restore --host 'localhost' --port 5432 --username "postgres" --dbname "mydatabase" --no-password --clean "/home/dinesh/db/mydb.backup"

How to get the result of OnPostExecute() to main activity because AsyncTask is a separate class?

You can do it in a few lines, just override onPostExecute when you call your AsyncTask. Here is an example for you:

new AasyncTask()
{
    @Override public void onPostExecute(String result)
    {
       // do whatever you want with result 
    }
}.execute(a.targetServer);

I hope it helped you, happy codding :)

Pandas group-by and sum

A variation on the .agg() function; provides the ability to (1) persist type DataFrame, (2) apply averages, counts, summations, etc. and (3) enables groupby on multiple columns while maintaining legibility.

df.groupby(['att1', 'att2']).agg({'att1': "count", 'att3': "sum",'att4': 'mean'})

using your values...

df.groupby(['Name', 'Fruit']).agg({'Number': "sum"})

ORA-00979 not a group by expression

Too bad Oracle has limitations like these. Sure, the result for a column not in the GROUP BY would be random, but sometimes you want that. Silly Oracle, you can do this in MySQL/MSSQL.

BUT there is a work around for Oracle:

While the following line does not work

SELECT unique_id_col, COUNT(1) AS cnt FROM yourTable GROUP BY col_A;

You can trick Oracle with some 0's like the following, to keep your column in scope, but not group by it (assuming these are numbers, otherwise use CONCAT)

SELECT MAX(unique_id_col) AS unique_id_col, COUNT(1) AS cnt 
FROM yourTable GROUP BY col_A, (unique_id_col*0 + col_A);

What is hashCode used for? Is it unique?

After learning what it is all about, I thought to write a hopefully simpler explanation via analogy:

Summary: What is a hashcode?

  • It's a fingerprint. We can use this finger print to identify people of interest.

Read below for more details:

Think of a Hashcode as us trying to To Uniquely Identify Someone

I am a detective, on the look out for a criminal. Let us call him Mr Cruel. (He was a notorious murderer when I was a kid -- he broke into a house kidnapped and murdered a poor girl, dumped her body and he's still out on the loose - but that's a separate matter). Mr Cruel has certain peculiar characteristics that I can use to uniquely identify him amongst a sea of people. We have 25 million people in Australia. One of them is Mr Cruel. How can we find him?

Bad ways of Identifying Mr Cruel

Apparently Mr Cruel has blue eyes. That's not much help because almost half the population in Australia also has blue eyes.

Good ways of Identifying Mr Cruel

What else can i use? I know: I will use a fingerprint!

Advantages:

  • It is really really hard for two people to have the same finger print (not impossible, but extremely unlikely).
  • Mr Cruel's fingerprint will never change.
  • Every single part of Mr Cruel's entire being: his looks, hair colour, personality, eating habits etc must (ideally) be reflected in his fingerprint, such that if he has a brother (who is very similar but not the same) - then both should have different finger prints. I say "should" because we cannot guarantee 100% that two people in this world will have different fingerprints.
  • But we can always guarantee that Mr Cruel will always have the same finger print - and that his fingerprint will NEVER change.

The above characteristics generally make for good hash functions.

So what's the deal with 'Collisions'?

So imagine if I get a lead and I find someone matching Mr Cruel's fingerprints. Does this mean I have found Mr Cruel?

........perhaps! I must take a closer look. If i am using SHA256 (a hashing function) and I am looking in a small town with only 5 people - then there is a very good chance I found him! But if I am using MD5 (another famous hashing function) and checking for fingerprints in a town with +2^1000 people, then it is a fairly good possibility that two entirely different people might have the same fingerprint.

So what is the benefit of all this anyways?

The only real benefit of hashcodes is if you want to put something in a hash table - and with hash tables you'd want to find objects quickly - and that's where the hash code comes in. They allow you to find things in hash tables really quickly. It's a hack that massively improves performance, but at a small expense of accuracy.

So let's imagine we have a hash table filled with people - 25 million suspects in Australia. Mr Cruel is somewhere in there..... How can we find him really quickly? We need to sort through them all: to find a potential match, or to otherwise acquit potential suspects. You don't want to consider each person's unique characteristics because that would take too much time. What would you use instead? You'd use a hashcode! A hashcode can tell you if two people are different. Whether Joe Bloggs is NOT Mr Cruel. If the prints don't match then you know it's definitely NOT Mr Cruel. But, if the finger prints do match then depending on the hash function you used, chances are already fairly good you found your man. But it's not 100%. The only way you can be certain is to investigate further: (i) did he/she have an opportunity/motive, (ii) witnesses etc etc.

When you are using computers if two objects have the same hash code value, then you again need to investigate further whether they are truly equal. e.g. You'd have to check whether the objects have e.g. the same height, same weight etc, if the integers are the same, or if the customer_id is a match, and then come to the conclusion whether they are the same. this is typically done perhaps by implementing an IComparer or IEquality interfaces.

Key Summary

So basically a hashcode is a finger print.

Digital Fingerprint - Picture attribute to Pixabay - Freely available for use at: https://pixabay.com/en/finger-fingerprint-security-digital-2081169/

  1. Two different people/objects can theoretically still have the same fingerprint. Or in other words. If you have two fingerprints that are the same.........then they need not both come from the same person/object.
  2. Buuuuuut, the same person/object will always return the same fingerprint.
  3. Which means that if two objects return different hash codes then you know for 100% certainty that those objects are different.

It takes a good 3 minutes to get your head around the above. Perhaps read it a few times till it makes sense. I hope this helps someone because it took a lot of grief for me to learn it all!

What is compiler, linker, loader?

  • Compiler : Which convert Human understandable format into machine understandable format
  • Linker : Which convert machine understandable format into Operating system understandable format
  • Loader : is entity which actually load and runs the program into RAM

Linker & Interpreter are mutually exclusive Interpreter getting code line by line and execute line by line.

iOS change navigation bar title font and color

ADD this single line code in your App Delegate - Did Finish Lauch. It will change Font, color of navigation bar throughout the application.

UINavigationBar.appearance().titleTextAttributes = [NSAttributedString.Key.foregroundColor: UIColor.white, NSAttributedString.Key.font: UIFont(name: "YOUR FONT NAME", size: 25.0)!]

How to change the foreign key referential action? (behavior)

You can simply use one query to rule them all: ALTER TABLE products DROP FOREIGN KEY oldConstraintName, ADD FOREIGN KEY (product_id, category_id) REFERENCES externalTableName (foreign_key_name, another_one_makes_composite_key) ON DELETE CASCADE ON UPDATE CASCADE

Sorting HTML table with JavaScript

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<!DOCTYPE html>
<html>
<head>
<style>
  table, td, th {
    border: 1px solid;
    border-collapse: collapse;
  }
  td , th {
    padding: 5px;
    width: 100px;
  }
  th {
    background-color: lightgreen;
  }
</style>
</head>
<body>

<h2>JavaScript Array Sort</h2>

<p>Click the buttons to sort car objects on age.</p>

<p id="demo"></p>

<script>
var nameArrow = "", yearArrow = "";
var cars = [
  {type:"Volvo", year:2016},
  {type:"Saab", year:2001},
  {type:"BMW", year:2010}
];
yearACS = true;
function sortYear() {
  if (yearACS) {
    nameArrow = "";
    yearArrow = "";
    cars.sort(function(a,b) {
      return a.year - b.year;
    });
    yearACS = false;
  }else {
    nameArrow = "";
    yearArrow = "";
    cars.sort(function(a,b) {
      return b.year - a.year;
    });
    yearACS = true;
  }
  displayCars();
}
nameACS = true;
function sortName() {
  if (nameACS) {
    nameArrow = "";
    yearArrow = "";
    cars.sort(function(a,b) {
      x = a.type.toLowerCase();
      y = b.type.toLowerCase();
      if (x > y) {return 1;}
      if (x < y) {return -1};
      return 0;
    });
    nameACS = false;
  } else {
    nameArrow = "";
    yearArrow = "";
    cars.sort(function(a,b) {
      x = a.type.toUpperCase();
      y = b.type.toUpperCase();
      if (x > y) { return -1};
      if (x <y) { return 1 };
      return 0;
    });
    nameACS = true;
  }
  displayCars();
}

displayCars();

function displayCars() {
  var txt = "<table><tr><th onclick='sortName()'>name " + nameArrow + "</th><th onclick='sortYear()'>year " + yearArrow + "</th><tr>";
  for (let i = 0; i < cars.length; i++) {
    txt += "<tr><td>"+ cars[i].type + "</td><td>" + cars[i].year + "</td></tr>";
  }
  txt += "</table>";
  document.getElementById("demo").innerHTML = txt;
}

</script>

</body>
</html>
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CSV parsing in Java - working example..?

i had to use a csv parser about 5 years ago. seems there are at least two csv standards: http://en.wikipedia.org/wiki/Comma-separated_values and what microsoft does in excel.

i found this libaray which eats both: http://ostermiller.org/utils/CSV.html, but afaik, it has no way of inferring what data type the columns were.

ASP.NET Web API application gives 404 when deployed at IIS 7

While the marked answer gets it working, all you really need to add to the webconfig is:

    <handlers>
      <!-- Your other remove tags-->
      <remove name="UrlRoutingModule-4.0"/>
      <!-- Your other add tags-->
      <add name="UrlRoutingModule-4.0" path="*" verb="*" type="System.Web.Routing.UrlRoutingModule" preCondition=""/>
    </handlers>

Note that none of those have a particular order, though you want your removes before your adds.

The reason that we end up getting a 404 is because the Url Routing Module only kicks in for the root of the website in IIS. By adding the module to this application's config, we're having the module to run under this application's path (your subdirectory path), and the routing module kicks in.

Google Chrome forcing download of "f.txt" file

Seems related to https://groups.google.com/forum/#!msg/google-caja-discuss/ite6K5c8mqs/Ayqw72XJ9G8J.

The so-called "Rosetta Flash" vulnerability is that allowing arbitrary yet identifier-like text at the beginning of a JSONP response is sufficient for it to be interpreted as a Flash file executing in that origin. See for more information: http://miki.it/blog/2014/7/8/abusing-jsonp-with-rosetta-flash/

JSONP responses from the proxy servlet now: * are prefixed with "/**/", which still allows them to execute as JSONP but removes requester control over the first bytes of the response. * have the response header Content-Disposition: attachment.

Saving binary data as file using JavaScript from a browser

This is possible if the browser supports the download property in anchor elements.

var sampleBytes = new Int8Array(4096);

var saveByteArray = (function () {
    var a = document.createElement("a");
    document.body.appendChild(a);
    a.style = "display: none";
    return function (data, name) {
        var blob = new Blob(data, {type: "octet/stream"}),
            url = window.URL.createObjectURL(blob);
        a.href = url;
        a.download = name;
        a.click();
        window.URL.revokeObjectURL(url);
    };
}());

saveByteArray([sampleBytes], 'example.txt');


JSFiddle: http://jsfiddle.net/VB59f/2

Read file content from S3 bucket with boto3

Using the client instead of resource:

s3 = boto3.client('s3')
bucket='bucket_name'
result = s3.list_objects(Bucket = bucket, Prefix='/something/')
for o in result.get('Contents'):
    data = s3.get_object(Bucket=bucket, Key=o.get('Key'))
    contents = data['Body'].read()
    print(contents)

socket.shutdown vs socket.close

Here's one explanation:

Once a socket is no longer required, the calling program can discard the socket by applying a close subroutine to the socket descriptor. If a reliable delivery socket has data associated with it when a close takes place, the system continues to attempt data transfer. However, if the data is still undelivered, the system discards the data. Should the application program have no use for any pending data, it can use the shutdown subroutine on the socket prior to closing it.

Get first row of dataframe in Python Pandas based on criteria

For the point that 'returns the value as soon as you find the first row/record that meets the requirements and NOT iterating other rows', the following code would work:

def pd_iter_func(df):
    for row in df.itertuples():
        # Define your criteria here
        if row.A > 4 and row.B > 3:
            return row

It is more efficient than Boolean Indexing when it comes to a large dataframe.

To make the function above more applicable, one can implements lambda functions:

def pd_iter_func(df: DataFrame, criteria: Callable[[NamedTuple], bool]) -> Optional[NamedTuple]:
    for row in df.itertuples():
        if criteria(row):
            return row

pd_iter_func(df, lambda row: row.A > 4 and row.B > 3)

As mentioned in the answer to the 'mirror' question, pandas.Series.idxmax would also be a nice choice.

def pd_idxmax_func(df, mask):
    return df.loc[mask.idxmax()]

pd_idxmax_func(df, (df.A > 4) & (df.B > 3))

ASP.NET MVC Conditional validation

There's a much better way to add conditional validation rules in MVC3; have your model inherit IValidatableObject and implement the Validate method:

public class Person : IValidatableObject
{
    public string Name { get; set; }
    public bool IsSenior { get; set; }
    public Senior Senior { get; set; }

    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext) 
    { 
        if (IsSenior && string.IsNullOrEmpty(Senior.Description)) 
            yield return new ValidationResult("Description must be supplied.");
    }
}

Read more at Introducing ASP.NET MVC 3 (Preview 1).

Keep values selected after form submission

Since WordPress already uses jQuery you can try something like this:

var POST=<?php echo json_encode($_POST); ?>;
for(k in POST){
  $("#"+k).val(POST[k]);
}

How to scroll to top of a div using jQuery?

Or, for less code, inside your click you place:

setTimeout(function(){ 

$('#DIV_ID').scrollTop(0);

}, 500);

c# why can't a nullable int be assigned null as a value

What Harry S says is exactly right, but

int? accom = (accomStr == "noval" ? null : (int?)Convert.ToInt32(accomStr));

would also do the trick. (We Resharper users can always spot each other in crowds...)

Redis - Connect to Remote Server

I was struggling with the remote connection to Redis for some days. Finally I made it. Here is the full check list I put together to follow to get connected. Some of solutions are given in the answers above. Yet I wanted my answer to be a nano-wiki on the subject:) I added some useful links too.

If redis works locally:

$ redis-cli
127.0.0.1:6379>ping
PONG
127.0.0.1:6379>

If the password is not set

See /etc/redis/redis.conf config (this is default locaion for Ubuntu 18.04, you may have it in the different location):

# The following line should be commented
# requirepass <some pass if any>

If the protected mode is set to 'no' in the config:

# The following line should be uncommented
protected-mode no

if the IP binding is open for an access from internet in the config:

# The following line should be commented
# bind 127.0.0.1 ::1

If the Linux firewall allows connections

(here for Ubuntu 18.04) Check it allows for incoming internet traffic to go to port 6379 (the Redis default port)

# To check if it the port is open
$ sudo ufw status
Status: active

To                         Action      From
--                         ------      ----
...
6379/tcp                   ALLOW       Anywhere
6379/tcp (v6)              ALLOW       Anywhere (v6)
...

# To open the port
$ sudo ufw allow 6379/tcp

Restart Redis service

Do not forget to restart the Redis service for changes to take effect and see it is running:

$ sudo systemctl restart redis.service
$ sudo systemctl status redis

Check if it works as a remote server

from your command line use redis-cli as if Redis server were on the remote server:

$ redis-cli -h <your-server-ip>
<your-server-ip>:6379> ping
PONG
<your-server-ip>:6379> exit
$

If you can ping-PONG your Redis server via your internet server connected as a remote server than the remote Redis connection works.

Security Warning

All the above makes your Redis data to be completely open to anybody from the internet.

To basically secure Redis use requirepass and protected-mode yes settings in Redis config (see above) and block the dangerous Redis commands (see the link above), for a deeper understanding see this article and Redis site security section ).

Useful links

Some links to help How to install and secure Redis on Ubuntu 18.04 and how to setup Ubuntu 18.04 firewall.

Hope it helps.

What is the worst programming language you ever worked with?

First, a few caveats: I tend to give a pass to languages that serve their intended purpose well enough, but get shoehorned by the corporate world into doing more than their designers intended. For that reason, I give a pass to VB and its VB-office variants. For quick prototyping, VB was hard to beat. It failed massively when people tried to use it for enterprise-level work. Same for Perl, which is a great scripting utility which somehow got promoted to the CGI language du jour back in the day.

But a language that fails to meet expectations, even on its own terms? For me, that's no contest: JavaScript, for three big reasons:

  1. lack of decent debugging capabilities (Firebug helps, but it's not enough),
  2. the way it simply halts whenever there's an error, forcing the programmer to add alert("in functionX") just to make sure you made it to functionX, and
  3. its infuriatingly obscure error messages.

And if I were allowed to choose a framework, it's likewise an easy choice: JSF and IceFaces.

get the value of input type file , and alert if empty

<script type="text/javascript">
$(document).ready(function() {
    $('#upload').bind("click",function() 
    { 
        var imgVal = $('#uploadImage').val(); 
        if(imgVal=='') 
        { 
            alert("empty input file"); 

        } 
        return false; 

    }); 
});
</script> 

<input type="file" name="image" id="uploadImage" size="30" /> 
<input type="submit" name="upload" id="upload"  class="send_upload" value="upload" /> 

Replacing a fragment with another fragment inside activity group

you can use simple code its work for transaction

Fragment newFragment = new MainCategoryFragment();
FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.replace(R.id.content_frame_NavButtom, newFragment);
ft.commit(); 

Onclick event to remove default value in a text input field

u can use placeholder and when u write a text on the search box placeholder will hidden. Thanks

<input placeholder="Search" type="text" />

Git: Recover deleted (remote) branch

The data still exists out in github, you can create a new branch from the old data:

git checkout origin/BranchName #get a readonly pointer to the old branch
git checkout –b BranchName #create a new branch from the old
git push origin BranchName #publish the new branch

Generate UML Class Diagram from Java Project

I´d say MoDisco is by far the most powerful one (though probably not the easiest one to work with).

MoDisco is a generic reverse engineering framework (so that you can customize your reverse engineering project, with MoDisco you can even reverse engineer the behaviour of the java methods, not only the structure and signatures) but also includes some predefined features like the generation of class diagrams out of Java code that you need.

Printing Lists as Tabular Data

I found this just looking for a way to output simple columns. If you just need no-fuss columns, then you can use this:

print("Titlex\tTitley\tTitlez")
for x, y, z in data:
    print(x, "\t", y, "\t", z)

EDIT: I was trying to be as simple as possible, and thereby did some things manually instead of using the teams list. To generalize to the OP's actual question:

#Column headers
print("", end="\t")
for team in teams_list:
    print(" ", team, end="")
print()
# rows
for team, row in enumerate(data):
    teamlabel = teams_list[team]
    while len(teamlabel) < 9:
        teamlabel = " " + teamlabel
    print(teamlabel, end="\t")
    for entry in row:
        print(entry, end="\t")
    print()

Ouputs:

          Man Utd  Man City  T Hotspur
  Man Utd       1       2       1   
 Man City       0       1       0   
T Hotspur       2       4       2   

But this no longer seems any more simple than the other answers, with perhaps the benefit that it doesn't require any more imports. But @campkeith's answer already met that and is more robust as it can handle a wider variety of label lengths.

Need a query that returns every field that contains a specified letter

select *
from table
where keyword like '%a%'
and keyword like '%b%'

ps This will be super slow. You may want to investigate full text indexing solutions.

How to check if an appSettings key exists?

var isAlaCarte = 
    ConfigurationManager.AppSettings.AllKeys.Contains("IsALaCarte") && 
    bool.Parse(ConfigurationManager.AppSettings.Get("IsALaCarte"));

(Excel) Conditional Formatting based on Adjacent Cell Value

I don't know if maybe it's a difference in Excel version but this question is 6 years old and the accepted answer didn't help me so this is what I figured out:

Under Conditional Formatting > Manage Rules:

  1. Make a new rule with "Use a formula to determine which cells to format"
  2. Make your rule, but put a dollar sign only in front of the letter: $A2<$B2
  3. Under "Applies to", Manually select the second column (It would not work for me if I changed the value in the box, it just kept snapping back to what was already there), so it looks like $B$2:$B$100 (assuming you have 100 rows)

This worked for me in Excel 2016.

jQuery to remove an option from drop down list, given option's text/value

$('#id option').remove();

This will clear the Drop Down list. if you want to clear to select value then $("#id option:selected").remove();

PostgreSQL Autoincrement

In the context of the asked question and in reply to the comment by @sereja1c, creating SERIAL implicitly creates sequences, so for the above example-

CREATE TABLE foo (id SERIAL,bar varchar);

CREATE TABLE would implicitly create sequence foo_id_seq for serial column foo.id. Hence, SERIAL [4 Bytes] is good for its ease of use unless you need a specific datatype for your id.

Hibernate Delete query

instead of using

session.delete(object)

use

getHibernateTemplate().delete(object)

In both place for select query and also for delete use getHibernateTemplate()

In select query you have to use DetachedCriteria or Criteria

Example for select query

List<foo> fooList = new ArrayList<foo>();
DetachedCriteria queryCriteria = DetachedCriteria.forClass(foo.class);
queryCriteria.add(Restrictions.eq("Column_name",restriction));
fooList = getHibernateTemplate().findByCriteria(queryCriteria);

In hibernate avoid use of session,here I am not sure but problem occurs just because of session use

Detect if checkbox is checked or unchecked in Angular.js ng-change event

You could just use the bound ng-model (answers[item.questID]) value itself in your ng-change method to detect if it has been checked or not.

Example:-

<input type="checkbox" ng-model="answers[item.questID]" 
     ng-change="stateChanged(item.questID)" /> <!-- Pass the specific id -->

and

$scope.stateChanged = function (qId) {
   if($scope.answers[qId]){ //If it is checked
       alert('test');
   }
}

Delete files or folder recursively on Windows CMD

dir /b %temp% >temp.list
for /f "delims=" %%a in (temp.list) do call rundll32.exe advpack.dll,DelNodeRunDLL32 "%temp%\%%a"

Difference between "managed" and "unmanaged"

Managed code is a differentiation coined by Microsoft to identify computer program code that requires and will only execute under the "management" of a Common Language Runtime virtual machine (resulting in Bytecode).

http://en.wikipedia.org/wiki/Managed_code

http://www.developer.com/net/cplus/article.php/2197621/Managed-Unmanaged-Native-What-Kind-of-Code-Is-This.htm

Installing Homebrew on OS X

How To Set Up Your Mac for Homebrew

Step 1

Check you have already Install the Xcode. Run the below command in your terminal

/usr/bin/xcodebuild -version

It will print the below sample output:

Xcode 12.3 Build version 12C33

Step 2

Now Open Xcode:

  1. Select preferences
  2. Select location tab
  3. Now in command Line Tool select your Xcode version from dropdown menu

Step 3

In terminal run below command:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Note : if you have M1 Chip Mac run the below command, close terminal and open the terminal again

echo "export PATH=/opt/homebrew/bin:$PATH" >> ~/.zshrc

Turning off hibernate logging console output

I managed to stop by adding those 2 lines

log4j.logger.org.hibernate.orm.deprecation=error

log4j.logger.org.hibernate=error

Bellow is what my log4j.properties looks like, i just leave some commented lines explaining the log level

# Root logger option
#Level/rules TRACE < DEBUG < INFO < WARN < ERROR < FATAL.
#FATAL: shows messages at a FATAL level only
#ERROR: Shows messages classified as ERROR and FATAL
#WARNING: Shows messages classified as WARNING, ERROR, and FATAL
#INFO: Shows messages classified as INFO, WARNING, ERROR, and FATAL
#DEBUG: Shows messages classified as DEBUG, INFO, WARNING, ERROR, and FATAL
#TRACE : Shows messages classified as TRACE,DEBUG, INFO, WARNING, ERROR, and FATAL
#ALL : Shows messages classified as TRACE,DEBUG, INFO, WARNING, ERROR, and FATAL
#OFF : No log messages display


log4j.rootLogger=INFO, file, console

log4j.logger.main=DEBUG
log4j.logger.org.hibernate.orm.deprecation=error
log4j.logger.org.hibernate=error

#######################################
# Direct log messages to a log file
log4j.appender.file.Threshold=ALL
log4j.appender.file.file=logs/MyProgram.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss,SSS} %-5p %c{1} - %m%n

# set file size limit
log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.MaxFileSize=5MB
log4j.appender.file.MaxBackupIndex=50


#############################################
# Direct log messages to System Out
log4j.appender.console.Threshold=INFO
log4j.appender.console.Target=System.out
log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=%d{HH:mm:ss} %-5p %c{1} - %m%n

Erase whole array Python

Now to answer the question that perhaps you should have asked, like "I'm getting 100 floats form somewhere; do I need to put them in an array or list before I find the minimum?"

Answer: No, if somewhere is a iterable, instead of doing this:

temp = []
for x in somewhere:
   temp.append(x)
answer = min(temp)

you can do this:

answer = min(somewhere)

Example:

answer = min(float(line) for line in open('floats.txt'))

LDAP server which is my base dn

The base dn is dc=example,dc=com.

I don't know about openca, but I will try this answer since you got very little traffic so far.

A base dn is the point from where a server will search for users. So I would try to simply use admin as a login name.

If openca behaves like most ldap aware applications, this is what is going to happen :

  1. An ldap search for the user admin will be done by the server starting at the base dn (dc=example,dc=com).
  2. When the user is found, the full dn (cn=admin,dc=example,dc=com) will be used to bind with the supplied password.
  3. The ldap server will hash the password and compare with the stored hash value. If it matches, you're in.

Getting step 1 right is the hardest part, but mostly because we don't get to do it often. Things you have to look out for in your configuraiton file are :

  • The dn your application will use to bind to the ldap server. This happens at application startup, before any user comes to authenticate. You will have to supply a full dn, maybe something like cn=admin,dc=example,dc=com.
  • The authentication method. It is usually a "simple bind".
  • The user search filter. Look at the attribute named objectClass for your admin user. It will be either inetOrgPerson or user. There will be others like top, you can ignore them. In your openca configuration, there should be a string like (objectClass=inetOrgPerson). Whatever it is, make sure it matches your admin user's object Class. You can specify two object class with this search filter (|(objectClass=inetOrgPerson)(objectClass=user)).

Download an LDAP Browser, such as Apache's Directory Studio. Connect using your application's credentials, so you will see what your application sees.

How to scroll the page when a modal dialog is longer than the screen?

fixed positioning alone should have fixed that problem but another good workaround to avoid this issue is to place your modal divs or elements at the bottom of the page not within your sites layout. Most modal plugins give their modal positioning absolute to allow the user keep main page scrolling.

<html>
        <body>
        <!-- Put all your page layouts and elements


        <!-- Let the last element be the modal elemment  -->
        <div id="myModals">
        ...
        </div>

        </body>
</html>

Apply function to each column in a data frame observing each columns existing data type

A solution using retype() from hablar to coerce factors to character or numeric type depending on feasability. I'd use dplyr for applying max to each column.

Code

library(dplyr)
library(hablar)

# Retype() simplifies each columns type, e.g. always removes factors
d <- d %>% retype()

# Check max for each column
d %>% summarise_all(max)

Result

Not the new column types.

     v1 v2       v3 v4   
  <dbl> <chr> <dbl> <chr>
1 0.974 j      1.09 J   

Data

# Sample data borrowed from @joran
d <- data.frame(v1 = runif(10), v2 = letters[1:10], 
                v3 = rnorm(10), v4 = LETTERS[1:10],stringsAsFactors = TRUE)

Firestore Getting documents id from collection

Can get ID before add documents in database:

var idBefore =  this.afs.createId();
console.log(idBefore);

How to declare Global Variables in Excel VBA to be visible across the Workbook

You can do the following to learn/test the concept:

  1. Open new Excel Workbook and in Excel VBA editor right-click on Modules->Insert->Module

  2. In newly added Module1 add the declaration; Public Global1 As String

  3. in Worksheet VBA Module Sheet1(Sheet1) put the code snippet:

Sub setMe()
      Global1 = "Hello"
End Sub
  1. in Worksheet VBA Module Sheet2(Sheet2) put the code snippet:
Sub showMe()
    Debug.Print (Global1)
End Sub
  1. Run in sequence Sub setMe() and then Sub showMe() to test the global visibility/accessibility of the var Global1

Hope this will help.

CSS "color" vs. "font-color"

I know this is an old post but as MisterZimbu stated, the color property is defining the values of other properties, as the border-color and, with CSS3, of currentColor.

currentColor is very handy if you want to use the font color for other elements (as the background or custom checkboxes and radios of inner elements for example).

Example:

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_x000D_
.element {_x000D_
  color: green;_x000D_
  background: red;_x000D_
  display: block;_x000D_
  width: 200px;_x000D_
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  margin: 0;_x000D_
}_x000D_
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  border: solid 10px;_x000D_
  display: inline-block;_x000D_
  width: 60px;_x000D_
  height: 100px;_x000D_
  margin: 10px;_x000D_
}_x000D_
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.innerElement2 {_x000D_
  background: currentColor;_x000D_
  display: inline-block;_x000D_
  width: 60px;_x000D_
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  margin: 10px;_x000D_
}
_x000D_
<div class="element">_x000D_
  <div class="innerElement1"></div>_x000D_
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matplotlib savefig in jpeg format

Just install pillow with pip install pillow and it will work.

How to center horizontally div inside parent div

Just out of interest, if you want to center two or more divs (so they're side by side in the center), then here's how to do it:

<div style="text-align:center;">
    <div style="border:1px solid #000; display:inline-block;">Div 1</div>
    <div style="border:1px solid red; display:inline-block;">Div 2</div>
</div>   

Most efficient way to append arrays in C#?

You might not need to concatenate end result into contiguous array. Instead, keep appending to the list as suggested by Jon. In the end you'll have a jagged array (well, almost rectangular in fact). When you need to access an element by index, use following indexing scheme:

double x = list[i / sampleSize][i % sampleSize];

Iteration over jagged array is also straightforward:

for (int iRow = 0; iRow < list.Length; ++iRow) {
  double[] row = list[iRow];
  for (int iCol = 0; iCol < row.Length; ++iCol) {
    double x = row[iCol];
  }
}

This saves you memory allocation and copying at expense of slightly slower element access. Whether this will be a net performance gain depends on size of your data, data access patterns and memory constraints.

Java, Calculate the number of days between two dates

My best solution (so far) for calculating the number of days difference:

//  This assumes that you already have two Date objects: startDate, endDate
//  Also, that you want to ignore any time portions

Calendar startCale=new GregorianCalendar();
Calendar endCal=new GregorianCalendar();

startCal.setTime(startDate);
endCal.setTime(endDate);

endCal.add(Calendar.YEAR,-startCal.get(Calendar.YEAR));
endCal.add(Calendar.MONTH,-startCal.get(Calendar.MONTH));
endCal.add(Calendar.DATE,-startCal.get(Calendar.DATE));

int daysDifference=endCal.get(Calendar.DAY_OF_YEAR);

Note, however, that this assumes less than a year's difference!

How to play an android notification sound

Try this:

public void ringtone(){
    try {
        Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
        Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
        r.play();
     } catch (Exception e) {
         e.printStackTrace();
     }
}

Programmatically center TextView text

You can use the following to programmatically center TextView text in Kotlin:

textview.gravity = Gravity.CENTER

How to save final model using keras?

Saving a Keras model:

model = ...  # Get model (Sequential, Functional Model, or Model subclass)
model.save('path/to/location')

Loading the model back:

from tensorflow import keras
model = keras.models.load_model('path/to/location')

For more information, read Documentation

How to lookup JNDI resources on WebLogic?

I had a similar problem to this one. It got solved by deleting the java:comp/env/ prefix and using jdbc/myDataSource in the context lookup. Just as someone pointed out in the comments.

Is it possible to center text in select box?

Yes, it is possible. You can use text-align-last

text-align-last: center;

How to style CSS role

Sure you can do in this mode:

 #content[role="main"]{
       //style
    }

http://www.w3.org/TR/selectors/#attribute-selectors

What does yield mean in PHP?

This function is using yield:

function a($items) {
    foreach ($items as $item) {
        yield $item + 1;
    }
}

It is almost the same as this one without:

function b($items) {
    $result = [];
    foreach ($items as $item) {
        $result[] = $item + 1;
    }
    return $result;
}

The only one difference is that a() returns a generator and b() just a simple array. You can iterate on both.

Also, the first one does not allocate a full array and is therefore less memory-demanding.

Using grep to search for a string that has a dot in it

Escape dot. Sample command will be.

grep '0\.00'

Python 3.1.1 string to hex

You've already got some good answers, but I thought you might be interested in a bit of the background too.

Firstly you're missing the quotes. It should be:

"hello".encode("hex")

Secondly this codec hasn't been ported to Python 3.1. See here. It seems that they haven't yet decided whether or not these codecs should be included in Python 3 or implemented in a different way.

If you look at the diff file attached to that bug you can see the proposed method of implementing it:

import binascii
output = binascii.b2a_hex(input)

Excel 2007: How to display mm:ss format not as a DateTime (e.g. 73:07)?

One convenient trick to entering elapsed times into Excel is to have two zeros and a colon before the number of minutes, details follow. For copy and paste operations into Excel without have to worry about formatting at all one can use the format 00:XX:XX where XX are two digits totaling < 60. In that case, Excel will echo 0:XX:XX in the cell contents displayed and store the data as 12:XX:XX AM. If one pastes data in a 00:XXX:XX format into Excel, or 00:XX:XX where either XX > 59 this will be converted into a fraction of a day.

For example, 00:121:12 becomes 0.0841666666666667, which if multiplied by the number of seconds in a day, 86,400, becomes 7272 s. Next, 00:21:12 would by default show 0:21:12 stored as 12:21:12 AM. Finally, 00:21:60 becomes 0.0152777777777778, also a fraction of a day.

This suggestion is made merely to avoid having to worry about specific formatting in Excel, and letting the program worry about it. Note, for Excel data internally formatted as 12:XX:XX AM one can only use certain Excel commands, for example, one can take an average. However, subtraction will only work when the result is a positive number. Such that converting times into seconds, fractions of a day, or other real number is suggested for access to more complete arithmetic operation coverage.

For example, if one has a column of mixed time formats, or times that are negative and will not display, if one changes the number formatting to General, all the times will be converted to fractions of a day.

Get the data received in a Flask request

My problem was similar. I got a payload POST request when a user clicked a button from my slackbot. The Content-Type was application/x-www-form-urlencoded. I used Flask, Python3.

I tried this solution and it didn't work

@app.route('/process_data', methods=['POST'])
def process_data():
   req_data = request.get_json(force=True)
   language = req_data['language']
   return 'The language value is: {}'.format(language)

My solution 1 was:

from urllib.parse import parse_qs
# Some code
@ app.route('/slack/request_handler', methods=['POST'])
def request_handler():    
    # request.get_data() returned a bytestring
    # parse_qs() returned a dict from a bytestring. This dict has 1 pair
    # I tried payload_dict.keys() to see what keys in the dict and it had one key only
    payload_dict = parse_qs(request.get_data())

    # Get the value of the key from payload_dict
    # Value of the key from payload_dict is an array, length = 1
    payload_dict_value_arr = payload_dict[b'payload']

    # Get data from the index[0] of the array payload_dict_value_arr
    data = payload_dict_value_arr[0]   

    # convert a string (representation of a Dict)) to a Dict
    # Note that if you have single quotes as a part of your keys or values this will
    # fail due to improper character replacement.
    # This solution is only recommended if you have a strong aversion 
    # to the eval solution.
    datajson = json.loads(data)

    # get value of key "channel"
    channel = datajson["channel"]
    print(channel) {'id': 'D01ACC2E8S3', 'name': 'directmessage'}

My solution 2, a bit shorter:

@ app.route('/slack/request_handler', methods=['POST'])
def request_handler():
   payload = request.form  # return an ImmutableMultiDict with 1 pair

   a1 = payload['payload']  # get value of key 'payload'

   # Note that if you have single quotes as a part of your keys or values this will
   # fail due to improper character replacement.
   # convert a string (representation of a Dict)) to a Dict
   a2 = json.loads(a1)

   # get value of key "channel"
   channel = a2["channel"] 
   print(channel) # {'id': 'D01ACC2E8S3', 'name': 'directmessage'}

flask.Request.get_data , Unicode in Flask

Get encoding of a file in Windows

I wrote the #4 answer (at time of writing). But lately I have git installed on all my computers, so now I use @Sybren's solution. Here is a new answer that makes that solution handy from powershell (without putting all of git/usr/bin in the PATH, which is too much clutter for me).

Add this to your profile.ps1:

$global:gitbin = 'C:\Program Files\Git\usr\bin'
Set-Alias file.exe $gitbin\file.exe

And used like: file.exe --mime-encoding *. You must include .exe in the command for PS alias to work.

But if you don't customize your PowerShell profile.ps1 I suggest you start with mine: https://gist.github.com/yzorg/8215221/8e38fd722a3dfc526bbe4668d1f3b08eb7c08be0 and save it to ~\Documents\WindowsPowerShell. It's safe to use on a computer without git, but will write warnings when git is not found.

The .exe in the command is also how I use C:\WINDOWS\system32\where.exe from powershell; and many other OS CLI commands that are "hidden by default" by powershell, *shrug*.

What is the meaning of the CascadeType.ALL for a @ManyToOne JPA association

If you just want to delete the address assigned to the user and not to affect on User entity class you should try something like that:

@Entity
public class User {
   @OneToMany(mappedBy = "addressOwner", cascade = CascadeType.ALL)
   protected Set<Address> userAddresses = new HashSet<>();
}

@Entity 
public class Addresses {
   @ManyToOne(cascade = CascadeType.REFRESH) @JoinColumn(name = "user_id")
   protected User addressOwner;
}

This way you dont need to worry about using fetch in annotations. But remember when deleting the User you will also delete connected address to user object.

Converting file size in bytes to human-readable string

As of 2020, you can use file-size npm package, that supports formatting in IEC (power 1024, default), SI (power 1000), and JEDEC (Alternative SI Unit Notation).

npm install file-size

import filesize from "filesize";

// outputs: 186.46 MB
filesize(186457865).human('si');

// outputs: 177.82 MiB
filesize(186457865).human();

https://www.npmjs.com/package/file-size

Add Header and Footer for PDF using iTextsharp

pdfDoc.Open();
Paragraph para = new Paragraph("Hello World", new Font(Font.FontFamily.HELVETICA, 22));
para.Alignment = Element.ALIGN_CENTER;
pdfDoc.Add(para);
pdfDoc.Add(new Paragraph("\r\n"));
htmlparser.Parse(sr);
pdfDoc.Close();

How to open the Google Play Store directly from my Android application?

Go on Android Developer official link as tutorial step by step see and got the code for your application package from play store if exists or play store apps not exists then open application from web browser.

Android Developer official link

https://developer.android.com/distribute/tools/promote/linking.html

Linking to a Application Page

From a web site: https://play.google.com/store/apps/details?id=<package_name>

From an Android app: market://details?id=<package_name>

Linking to a Product List

From a web site: https://play.google.com/store/search?q=pub:<publisher_name>

From an Android app: market://search?q=pub:<publisher_name>

Linking to a Search Result

From a web site: https://play.google.com/store/search?q=<search_query>&c=apps

From an Android app: market://search?q=<seach_query>&c=apps

Get the correct week number of a given date

If you don't have .NET 5.0, extend the DateTime class to include week number.

public static class Extension {
    public static int Week(this DateTime date) {
        var day = (int)CultureInfo.CurrentCulture.Calendar.GetDayOfWeek(date);
        return CultureInfo.CurrentCulture.Calendar.GetWeekOfYear(date.AddDays(4 - (day == 0 ? 7 : day)), CalendarWeekRule.FirstFourDayWeek, DayOfWeek.Monday);
    }
}

How to stop a goroutine

You can't kill a goroutine from outside. You can signal a goroutine to stop using a channel, but there's no handle on goroutines to do any sort of meta management. Goroutines are intended to cooperatively solve problems, so killing one that is misbehaving would almost never be an adequate response. If you want isolation for robustness, you probably want a process.

How to correctly use "section" tag in HTML5?

In the W3 wiki page about structuring HTML5, it says:

<section>: Used to either group different articles into different purposes or subjects, or to define the different sections of a single article.

And then displays an image that I cleaned up:

enter image description here

It's also important to know how to use the <article> tag (from the same W3 link above):

<article> is related to <section>, but is distinctly different. Whereas <section> is for grouping distinct sections of content or functionality, <article> is for containing related individual standalone pieces of content, such as individual blog posts, videos, images or news items. Think of it this way - if you have a number of items of content, each of which would be suitable for reading on their own, and would make sense to syndicate as separate items in an RSS feed, then <article> is suitable for marking them up.

In our example, <section id="main"> contains blog entries. Each blog entry would be suitable for syndicating as an item in an RSS feed, and would make sense when read on its own, out of context, therefore <article> is perfect for them:

<section id="main">
    <article>
      <!-- first blog post -->
    </article>

    <article>
      <!-- second blog post  -->
    </article>

    <article>
      <!-- third blog post -->
    </article>
</section>

Simple huh? Be aware though that you can also nest sections inside articles, where it makes sense to do so. For example, if each one of these blog posts has a consistent structure of distinct sections, then you could put sections inside your articles as well. It could look something like this:

<article>
  <section id="introduction">
  </section>

  <section id="content">
  </section>

  <section id="summary">
  </section>
</article>

pandas three-way joining multiple dataframes on columns

Simple Solution:

If the column names are similar:

 df1.merge(df2,on='col_name').merge(df3,on='col_name')

If the column names are different:

df1.merge(df2,left_on='col_name1', right_on='col_name2').merge(df3,left_on='col_name1', right_on='col_name3').drop(columns=['col_name2', 'col_name3']).rename(columns={'col_name1':'col_name'})