Programs & Examples On #Sharpssh

SharpSSH is a .NET framework library for connecting to and retrieving files from an SSH/SFTP server.

How to insert a SQLite record with a datetime set to 'now' in Android application?

You cannot use the datetime function using the Java wrapper "ContentValues". Either you can use :

  • SQLiteDatabase.execSQL so you can enter a raw SQL query.

    mDb.execSQL("INSERT INTO "+DATABASE_TABLE+" VALUES (null, datetime()) ");
    
  • Or the java date time capabilities :

    // set the format to sql date time
    SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); 
    Date date = new Date();
    ContentValues initialValues = new ContentValues(); 
    initialValues.put("date_created", dateFormat.format(date));
    long rowId = mDb.insert(DATABASE_TABLE, null, initialValues);
    

Difference between add(), replace(), and addToBackStack()

Important thing to be noticed:

Difference between Replace and Replace with backstack is whenever we use only replace then the fragment is destroyed ( ondestroy() is called ) and when we use replace with backstack then fragments onDestroy() is not called ( i.e when back button is pressed fragment is invoked with its onCreateView())

Table scroll with HTML and CSS

This work for me

Demo: jsfiddle

$(function() 
{
    Fixed_Header();
});

function Fixed_Header()
{
    $('.User_Table thead').css({'position': 'absolute'});
    $('.User_Table tbody tr:eq("2") td').each(function(index,e){
        $('.User_Table thead tr th:eq("'+index+'")').css({'width' : $(this).outerWidth() +"px" });
    });
    var Header_Height = $('.User_Table thead').outerHeight();
    $('.User_Table thead').css({'margin-top' : "-"+Header_Height+"px"});
    $('.User_Table').css({'margin-top' : Header_Height+"px"});
}

What causes a java.lang.StackOverflowError

When a function call is invoked by a Java application, a stack frame is allocated on the call stack. The stack frame contains the parameters of the invoked method, its local parameters, and the return address of the method.

The return address denotes the execution point from which, the program execution shall continue after the invoked method returns. If there is no space for a new stack frame then, the StackOverflowError is thrown by the Java Virtual Machine (JVM).

The most common case that can possibly exhaust a Java application’s stack is recursion.

Please Have a look

How to solve StackOverflowError

How to add Button over image using CSS?

I like TryingToImprove's answer. I've essentially taken his answer and simplified it down to the barebones css to accomplish the same thing. I think it's a lot easier to chew on.

HTML:

<div class="content">
    <img src="http://placehold.it/182x121"/> 
    <a href="#">Counter-Strike 1.6 Steam</a>
</div>        

CSS:

.content{    
    display:inline-block;
    position:relative;
}

.content a {
    position:absolute;
    bottom:5px;
    right:5px;
}

Working fiddle here.

How to get all key in JSON object (javascript)

var input = {"document":
  {"people":[
    {"name":["Harry Potter"],"age":["18"],"gender":["Male"]},
    {"name":["hermione granger"],"age":["18"],"gender":["Female"]},
  ]}
}

var keys = [];
for(var i = 0;i<input.document.people.length;i++)
{
    Object.keys(input.document.people[i]).forEach(function(key){
        if(keys.indexOf(key) == -1)
        {
            keys.push(key);
        }
    });
}
console.log(keys);

Python-Requests close http connection

I think a more reliable way of closing a connection is to tell the sever explicitly to close it in a way compliant with HTTP specification:

HTTP/1.1 defines the "close" connection option for the sender to signal that the connection will be closed after completion of the response. For example,

   Connection: close

in either the request or the response header fields indicates that the connection SHOULD NOT be considered `persistent' (section 8.1) after the current request/response is complete.

The Connection: close header is added to the actual request:

r = requests.post(url=url, data=body, headers={'Connection':'close'})

Using two values for one switch case statement

You can use:

case text1: case text4: 
     do stuff;
     break;

How to Identify port number of SQL server

  1. Open Run in your system.

  2. Type %windir%\System32\cliconfg.exe

  3. Click on ok button then check that the "TCP/IP Network Protocol Default Value Setup" pop-up is open.

  4. Highlight TCP/IP under the Enabled protocols window.

  5. Click the Properties button.

  6. Enter the new port number, then click OK.

enter image description here

How to indent/format a selection of code in Visual Studio Code with Ctrl + Shift + F

(This works at least up to version 1.52.0, 10 Dec 2020)


On macOS Visual Studio Code version 1.36.1 (2019)

Visual Studio Code version 1.36.1 (2019)

To auto-format the selection, use ?K ?F (the trick is that this is to be done in sequence, ?K first, followed by ?F).

Auto-format selection or document

To just indent (shift right) without auto-formatting, use ?]

Indent options

As in Keyboard Shortcuts (?K ?S, or from the menu as shown below)

Keyboard shortcuts

Does React Native styles support gradients?

Here is a good choice for gradients for both platforms iOS and Android:

https://github.com/react-native-community/react-native-linear-gradient

There are others approaches like expo, however react-native-linear-gradient have worked better for me.

<LinearGradient colors={['#4c669f', '#3b5998', '#192f6a']} style={styles.linearGradient}>
  <Text style={styles.buttonText}>
    Sign in with Facebook
  </Text>
</LinearGradient>

// Later on in your styles..
var styles = StyleSheet.create({
  linearGradient: {
    flex: 1,
    paddingLeft: 15,
    paddingRight: 15,
    borderRadius: 5
  },
  buttonText: {
    fontSize: 18,
    fontFamily: 'Gill Sans',
    textAlign: 'center',
    margin: 10,
    color: '#ffffff',
    backgroundColor: 'transparent',
  },
});

How to set HTTP header to UTF-8 using PHP which is valid in W3C validator?

First make sure the PHP files themselves are UTF-8 encoded.

The meta tag is ignored by some browser. If you only use ASCII-characters, it doesn't matter anyway.

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

header('Content-Type: text/html; charset=utf-8');

Find Number of CPUs and Cores per CPU using Command Prompt

In order to check the absence of physical sockets run:

wmic cpu get SocketDesignation

Simulating a click in jQuery/JavaScript on a link

Try this

function submitRequest(buttonId) {
    if (document.getElementById(buttonId) == null
            || document.getElementById(buttonId) == undefined) {
        return;
    }
    if (document.getElementById(buttonId).dispatchEvent) {
        var e = document.createEvent("MouseEvents");
        e.initEvent("click", true, true);
        document.getElementById(buttonId).dispatchEvent(e);
    } else {
        document.getElementById(buttonId).click();
    }
}

and you can use it like

submitRequest("target-element-id");

Entity framework left join

Please make your life easier (don't use join into group):

var query = from ug in UserGroups
            from ugp in UserGroupPrices.Where(x => x.UserGroupId == ug.Id).DefaultIfEmpty()
            select new 
            { 
                UserGroupID = ug.UserGroupID,
                UserGroupName = ug.UserGroupName,
                Price = ugp != null ? ugp.Price : 0 //this is to handle nulls as even when Price is non-nullable prop it may come as null from SQL (result of Left Outer Join)
            };

Disable Auto Zoom in Input "Text" tag - Safari on iPhone

In Angular you can use directives to prevent zooming on focus on IOS devices. No meta tag to preserve accessibility.

import { Directive, ElementRef, HostListener } from '@angular/core';

const MINIMAL_FONT_SIZE_BEFORE_ZOOMING_IN_PX = 16;

@Directive({ selector: '[noZoomiOS]' })

export class NoZoomiOSDirective {
  constructor(private el: ElementRef) {}

@HostListener('focus')
  onFocus() {
    this.setFontSize('');
  }

@HostListener('mousedown')
  onMouseDown() {
    this.setFontSize(`${MINIMAL_FONT_SIZE_BEFORE_ZOOMING_IN_PX}px`);
  }

private setFontSize(size: string) {
  const { fontSize: currentInputFontSize } = window.getComputedStyle(this.el.nativeElement, null);

  if (MINIMAL_FONT_SIZE_BEFORE_ZOOMING_IN_PX <= +currentInputFontSize.match(/\d+/)) {
      return;
   }

  const iOS = navigator.platform && /iPad|iPhone|iPod/.test(navigator.platform);
  iOS 
     && (this.el.nativeElement.style.fontSize = size);
 }
}

You can use it like this <input noZoomiOS > after you declare it in your *.module.ts

case in sql stored procedure on SQL Server

Try this

If @NewStatus  = 'InOffice' 
BEGIN
     Update tblEmployee set InOffice = -1 where EmpID = @EmpID
END
Else If @NewStatus  = 'OutOffice'
BEGIN
    Update tblEmployee set InOffice = -1 where EmpID = @EmpID
END
Else If @NewStatus  = 'Home'
BEGIN
    Update tblEmployee set Home = -1 where EmpID = @EmpID
END

Using Jquery Ajax to retrieve data from Mysql

This answer was for @
Neha Gandhi but I modified it for  people who use pdo and mysqli sing mysql functions are not supported. Here is the new answer 

    <html>
<!--Save this as index.php-->
      <script src="//code.jquery.com/jquery-1.9.1.js"></script>
        <script src="//ajax.aspnetcdn.com/ajax/jquery.validate/1.9/jquery.validate.min.js"></script>
    
     <script type="text/javascript">
    
     $(document).ready(function() {
    
        $("#display").click(function() {                
    
          $.ajax({    //create an ajax request to display.php
            type: "GET",
            url: "display.php",             
            dataType: "html",   //expect html to be returned                
            success: function(response){                    
                $("#responsecontainer").html(response); 
                //alert(response);
            }
    
        });
    });
    });
    
    </script>
    
    <body>
    <h3 align="center">Manage Student Details</h3>
    <table border="1" align="center">
       <tr>
           <td> <input type="button" id="display" value="Display All Data" /> </td>
       </tr>
    </table>
    <div id="responsecontainer" align="center">
    
    </div>
    </body>
    </html>

<?php
// save this as display.php


    // show errors 
error_reporting(E_ALL);
ini_set('display_errors', 1);
    //errors ends here 
// call the page for connecting to the db
require_once('dbconnector.php');
?>
<?php
$get_member =" SELECT 
empid, lastName, firstName, email, usercode, companyid, userid, jobTitle, cell, employeetype, address ,initials   FROM employees";
$user_coder1 = $con->prepare($get_member);
$user_coder1 ->execute();

echo "<table border='1' >
<tr>
<td align=center> <b>Roll No</b></td>
<td align=center><b>Name</b></td>
<td align=center><b>Address</b></td>
<td align=center><b>Stream</b></td></td>
<td align=center><b>Status</b></td>";

while($row =$user_coder1->fetch(PDO::FETCH_ASSOC)){
$firstName = $row['firstName'];
$empid = $row['empid'];
$lastName =    $row['lastName'];
$cell =    $row['cell'];

    echo "<tr>";
    echo "<td align=center>$firstName</td>";
    echo "<td align=center>$empid</td>";
    echo "<td align=center>$lastName </td>";
    echo "<td align=center>$cell</td>";
    echo "<td align=center>$cell</td>";
    echo "</tr>";
}
echo "</table>";
?>

<?php
// save this as dbconnector.php
function connected_Db(){

    $dsn  = 'mysql:host=localhost;dbname=mydb;charset=utf8';
    $opt  = array(
        PDO::ATTR_ERRMODE            => PDO::ERRMODE_EXCEPTION,
        PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC
    );
    #echo "Yes we are connected";
    return new PDO($dsn,'username','password', $opt);
    
}
$con = connected_Db();
if($con){
//echo "me  is connected ";
}
else {
//echo "Connection faid ";
exit();
}
?>

Named placeholders in string formatting

For very simple cases you can simply use a hardcoded String replace, no need for a library there:

    String url = "There's an incorrect value '%(value)' in column # %(column)";
    url = url.replace("%(value)", x); // 1
    url = url.replace("%(column)", y); // 2

WARNING: I just wanted to show the simplest code possible. Of course DO NOT use this for serious production code where security matters, as stated in the comments: escaping, error handling and security are an issue here. But in the worst case you now know why using a 'good' lib is required :-)

How to show the "Are you sure you want to navigate away from this page?" when changes committed?

To make this work in Chrome and Safari, you would have to do it like this

window.onbeforeunload = function(e) {
    return "Sure you want to leave?";
};

Reference: https://developer.mozilla.org/en/DOM/window.onbeforeunload

Is there a jQuery unfocus method?

I like the following approach as it works for all situations:

$(':focus').blur();

Return an empty Observable

Came here with a similar question, the above didn't work for me in: "rxjs": "^6.0.0", in order to generate an observable that emits no data I needed to do:

import {Observable,empty} from 'rxjs';
class ActivatedRouteStub {
  params: Observable<any> = empty();
}

How to fit a smooth curve to my data in R?

The other answers are all good approaches. However, there are a few other options in R that haven't been mentioned, including lowess and approx, which may give better fits or faster performance.

The advantages are more easily demonstrated with an alternate dataset:

sigmoid <- function(x)
{
  y<-1/(1+exp(-.15*(x-100)))
  return(y)
}

dat<-data.frame(x=rnorm(5000)*30+100)
dat$y<-as.numeric(as.logical(round(sigmoid(dat$x)+rnorm(5000)*.3,0)))

Here is the data overlaid with the sigmoid curve that generated it:

Data

This sort of data is common when looking at a binary behavior among a population. For example, this might be a plot of whether or not a customer purchased something (a binary 1/0 on the y-axis) versus the amount of time they spent on the site (x-axis).

A large number of points are used to better demonstrate the performance differences of these functions.

Smooth, spline, and smooth.spline all produce gibberish on a dataset like this with any set of parameters I have tried, perhaps due to their tendency to map to every point, which does not work for noisy data.

The loess, lowess, and approx functions all produce usable results, although just barely for approx. This is the code for each using lightly optimized parameters:

loessFit <- loess(y~x, dat, span = 0.6)
loessFit <- data.frame(x=loessFit$x,y=loessFit$fitted)
loessFit <- loessFit[order(loessFit$x),]

approxFit <- approx(dat,n = 15)

lowessFit <-data.frame(lowess(dat,f = .6,iter=1))

And the results:

plot(dat,col='gray')
curve(sigmoid,0,200,add=TRUE,col='blue',)
lines(lowessFit,col='red')
lines(loessFit,col='green')
lines(approxFit,col='purple')
legend(150,.6,
       legend=c("Sigmoid","Loess","Lowess",'Approx'),
       lty=c(1,1),
       lwd=c(2.5,2.5),col=c("blue","green","red","purple"))

Fits

As you can see, lowess produces a near perfect fit to the original generating curve. Loess is close, but experiences a strange deviation at both tails.

Although your dataset will be very different, I have found that other datasets perform similarly, with both loess and lowess capable of producing good results. The differences become more significant when you look at benchmarks:

> microbenchmark::microbenchmark(loess(y~x, dat, span = 0.6),approx(dat,n = 20),lowess(dat,f = .6,iter=1),times=20)
Unit: milliseconds
                           expr        min         lq       mean     median        uq        max neval cld
  loess(y ~ x, dat, span = 0.6) 153.034810 154.450750 156.794257 156.004357 159.23183 163.117746    20   c
            approx(dat, n = 20)   1.297685   1.346773   1.689133   1.441823   1.86018   4.281735    20 a  
 lowess(dat, f = 0.6, iter = 1)   9.637583  10.085613  11.270911  11.350722  12.33046  12.495343    20  b 

Loess is extremely slow, taking 100x as long as approx. Lowess produces better results than approx, while still running fairly quickly (15x faster than loess).

Loess also becomes increasingly bogged down as the number of points increases, becoming unusable around 50,000.

EDIT: Additional research shows that loess gives better fits for certain datasets. If you are dealing with a small dataset or performance is not a consideration, try both functions and compare the results.

Chart creating dynamically. in .net, c#

Add a reference to System.Windows.Form.DataVisualization, then add the appropriate using statement:

using System.Windows.Forms.DataVisualization.Charting;

private void CreateChart()
{
    var series = new Series("Finance");

    // Frist parameter is X-Axis and Second is Collection of Y- Axis
    series.Points.DataBindXY(new[] { 2001, 2002, 2003, 2004 }, new[] { 100, 200, 90, 150 });
    chart1.Series.Add(series);

}

How to drop a table if it exists?

I use:

if exists (select * 
           from sys.tables 
           where name = 'tableName' 
           and schema_id = schema_id('dbo'))
begin
    drop table dbo.tableName
end

insert vertical divider line between two nested divs, not full height

Try this. I set the blue box to float right, gave left and right a fixed height, and added a white border on the right of the left div. Also added rounded corners to more match your example (These won't work in ie 8 or less). I also took out the position: relative. You don't need it. Block level elements are set to position relative by default.

See it here: http://jsfiddle.net/ZSgLJ/

#left {
  float: left;
  width: 44%;
  margin: 0;
  padding: 0;
  border-right: 1px solid white;
  height:400px;
}

#right {
  position: relative;
  float: right;
  width: 49%;
  margin: 0;
  padding: 0;
  height:400px;
}

#blue_box {
  background-color:blue;
  border-radius: 10px;
  -moz-border-radius:10px;
  -webkit-border-radius: 10px;
  width: 45%;
  min-width: 400px;
  max-width: 600px;
  padding: 2%;
  float: right;
}

How do you create optional arguments in php?

Some notes that I also found useful:

  • Keep your default values on the right side.

    function whatever($var1, $var2, $var3="constant", $var4="another")
    
  • The default value of the argument must be a constant expression. It can't be a variable or a function call.

Adding a new line/break tag in XML

The easiest way to give a line break is to do the following :
1> Add the following in CSS - e{display:block}
2> Now wherever you want to give a line break, type -

<e></e>

Static method in a generic class?

Since static variables are shared by all instances of the class. For example if you are having following code

class Class<T> {
  static void doIt(T object) {
    // using T here 
  }
}

T is available only after an instance is created. But static methods can be used even before instances are available. So, Generic type parameters cannot be referenced inside static methods and variables

case-insensitive matching in xpath?

for selenium xpath lower-case will not work ... Translate will help Case 1 :

  1. using Attribute //*[translate(@id,'ABCDEFGHIJKLMNOPQRSTUVWXYZ','abcdefghijklmnopqrstuvwxyz')='login_field']
  2. Using any attribute //[translate(@,'ABCDEFGHIJKLMNOPQRSTUVWXYZ','abcdefghijklmnopqrstuvwxyz')='login_field']

Case 2 : (with contains) //[contains(translate(@id,'ABCDEFGHIJKLMNOPQRSTUVWXYZ','abcdefghijklmnopqrstuvwxyz'),'login_field')]

case 3 : for Text property //*[contains(translate(text(), 'ABCDEFGHIJKLMNOPQRSTUVWXYZ', 'abcdefghijklmnopqrstuvwxyz'),'username')]


QA Automator is automation management tool on cloud platform , where you can create, execute and maintenance the automation test scripts https://www.youtube.com/watch?v=iFk1Na_627U&t=53s

How to set up Android emulator proxy settings

The simplest and the best way is to do the following: This has been done for Android Emulator 2.2

  1. Click on Menu
  2. Click on Settings
  3. Click on Wireless & Networks
  4. Go to Mobile Networks
  5. Go to Access Point Names
  6. Here you will Telkila Internet, click on it.
  7. In the Edit access point section, input the "proxy" and "port"
  8. Also provide the Username and Password, rest of the fields leave them blank.

How do I correct this Illegal String Offset?

if(isset($rule["type"]) && ($rule["type"] == "radio") || ($rule["type"] == "checkbox") )
{
    if(!isset($data[$field]))
        $data[$field]="";
}

Cannot set property 'innerHTML' of null

There are different possible cause as discussed would just like to add this for someone who might have the same issue as mine.

In my case I had a missing close div as shown below

   <!DOCTYPE HTML>
   <html>
   <head>
   <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
   <title>Untitled Document</title>
   </head>
   <body>
   <div> //I am an open div
    <div id="hello"></div>
   <script type ="text/javascript">
       what();
       function what(){
          document.getElementById('hello').innerHTML = 'hi';
       };
   </script>
   </body>
   </html>

Missing a close div can result in disorganization of the transversal from child to parent or parent to child hence resulting in an error when you try to access an element in the DOM

Determine the number of NA values in a column

Try the colSums function

df <- data.frame(x = c(1,2,NA), y = rep(NA, 3))

colSums(is.na(df))

#x y 
#1 3 

How to access shared folder without giving username and password

I found one way to access the shared folder without giving the username and password.

We need to change the share folder protect settings in the machine where the folder has been shared.

Go to Control Panel > Network and sharing center > Change advanced sharing settings > Enable Turn Off password protect sharing option.

By doing the above settings we can access the shared folder without any username/password.

Ubuntu apt-get unable to fetch packages

Ran into a similar issue.

This is linked to using a non LTS version of Ubuntu called an "End of life version". As those have discontinued support. You can check if your Ubuntu is at the end of life version on this link.

The simplest solution is to do the following two steps:

  1. Backup your sources list sudo cp /etc/apt/sources.list /etc/apt/sources.list.backup
  2. Open the sources file /etc/apt/sources.list and rename all the instances of us.archive or archive in

    http://us.archive.ubuntu.com/ubuntu/

    to

    http://old-releases.ubuntu.com/ubuntu/

    Also do the same for the http://security.ubuntu.com/ubuntu/dists/saucy-security/universe/binary-i386/Packages

  3. Run sudo apt-get update after doing the above.

That should fix the issue.

Warning: Please update your ubuntu to an LTS version as soon as possible otherwise you won't be getting the latest security patches. This is definitely not a solution that you would deploy on production machines.

ERROR 1067 (42000): Invalid default value for 'created_at'

You can do it like this:

 CREATE TABLE `ttt` (
  `id` INT(11) UNSIGNED NOT NULL AUTO_INCREMENT,
  `t1` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t2` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t3` TIMESTAMP  NULL DEFAULT '0000-00-00 00:00:00',
  `t4` TIMESTAMP  NULL DEFAULT 0,
  PRIMARY KEY (`id`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;
  • Because the TIMESTAMP value is stored as Epoch Seconds, the timestamp value '1970-01-01 00:00:00' (UTC) is reserved since the second #0 is used to represent '0000-00-00 00:00:00'.
  • In MariaDB 5.5 and before there could only be one TIMESTAMP column per table that had CURRENT_TIMESTAMP defined as its default value. This limit has no longer applied since MariaDB 10.0.

see: https://mariadb.com/kb/en/mariadb/timestamp/

sample

MariaDB []> insert into ttt (id) VALUES (1),(2),(3);
Query OK, 3 rows affected (0.01 sec)
Records: 3  Duplicates: 0  Warnings: 0

MariaDB []> select * from ttt;
+----+---------------------+---------------------+---------------------+---------------------+
| id | t1                  | t2                  | t3                  | t4                  |
+----+---------------------+---------------------+---------------------+---------------------+
|  1 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
|  2 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
|  3 | 0000-00-00 00:00:00 | 2000-01-01 12:01:02 | 0000-00-00 00:00:00 | 0000-00-00 00:00:00 |
+----+---------------------+---------------------+---------------------+---------------------+
3 rows in set (0.00 sec)

MariaDB []>

Traversing text in Insert mode

Insert mode

Movement

hjkl

Notwithstanding what Pavel Shved said - that it is probably more advisable to get used to Escaping Insert mode - here is an example set of mappings for quick navigation within Insert mode:

" provide hjkl movements in Insert mode via the <Alt> modifier key
inoremap <A-h> <C-o>h
inoremap <A-j> <C-o>j
inoremap <A-k> <C-o>k
inoremap <A-l> <C-o>l

This will make Alt+h in Insert mode go one character left, Alt+j down and so on, analogously to hjkl in Normal mode.

You have to copy that code into your vimrc file to have it loaded every time you start vim (you can open that by typing :new $myvimrc starting in Normal mode).

Any Normal mode movements

Since the Alt modifier key is not mapped (to something important) by default, you can in the same fashion pull other (or all) functionality from Normal mode to Insert mode. E.g.:
Moving to the beginning of the current word with Alt+b:

inoremap <A-b> <C-o>b
inoremap <A-w> <C-o>w

(Other uses of Alt in Insert mode)

It is worth mentioning that there may be better uses for the Alt key than replicating Normal mode behaviour: e.g. here are mappings for copying from an adjacent line the portion from the current column till the end of the line:

" Insert the rest of the line below the cursor.
" Mnemonic: Elevate characters from below line
inoremap <A-e> 
    \<Esc>
    \jl
        \y$
    \hk
        \p
        \a
" Insert the rest of the line above the cursor.
" Mnemonic: Y depicts a funnel, through which the above line's characters pour onto the current line.
inoremap <A-y> 
    \<Esc>
    \kl
        \y$
    \hj
        \p
        \a

(I used \ line continuation and indentation to increase clarity. The commands are interpreted as if written on a single line.)

Built-in hotkeys for editing

CTRL-H   delete the character  in front of the cursor (same as <Backspace>)
CTRL-W   delete the word       in front of the cursor
CTRL-U   delete all characters in front of the cursor (influenced by the 'backspace' option)

(There are no notable built-in hotkeys for movement in Insert mode.)

Reference: :help insert-index


Command-line mode

This set of mappings makes the upper Alt+hjkl movements available in the Command-line:

" provide hjkl movements in Command-line mode via the <Alt> modifier key
cnoremap <A-h> <Left>
cnoremap <A-j> <Down>
cnoremap <A-k> <Up>
cnoremap <A-l> <Right>

Alternatively, these mappings add the movements both to Insert mode and Command-line mode in one go:

" provide hjkl movements in Insert mode and Command-line mode via the <Alt> modifier key
noremap! <A-h> <Left>
noremap! <A-j> <Down>
noremap! <A-k> <Up>
noremap! <A-l> <Right>

The mapping commands for pulling Normal mode commands to Command-line mode look a bit different from the Insert mode mapping commands (because Command-line mode lacks Insert mode's Ctrl+O):

" Normal mode command(s) go… --v <-- here
cnoremap <expr> <A-h> &cedit. 'h' .'<C-c>'
cnoremap <expr> <A-j> &cedit. 'j' .'<C-c>'
cnoremap <expr> <A-k> &cedit. 'k' .'<C-c>'
cnoremap <expr> <A-l> &cedit. 'l' .'<C-c>'

cnoremap <expr> <A-b> &cedit. 'b' .'<C-c>'
cnoremap <expr> <A-w> &cedit. 'w' .'<C-c>'

Built-in hotkeys for movement and editing

CTRL-B       cursor to beginning of command-line
CTRL-E       cursor to end       of command-line

CTRL-F       opens the command-line window (unless a different key is specified in 'cedit')

CTRL-H       delete the character  in front of the cursor (same as <Backspace>)
CTRL-W       delete the word       in front of the cursor
CTRL-U       delete all characters in front of the cursor

CTRL-P       recall previous command-line from history (that matches pattern in front of the cursor)
CTRL-N       recall next     command-line from history (that matches pattern in front of the cursor)
<Up>         recall previous command-line from history (that matches pattern in front of the cursor)
<Down>       recall next     command-line from history (that matches pattern in front of the cursor)
<S-Up>       recall previous command-line from history
<S-Down>     recall next     command-line from history
<PageUp>     recall previous command-line from history
<PageDown>   recall next     command-line from history

<S-Left>     cursor one word left
<C-Left>     cursor one word left
<S-Right>    cursor one word right
<C-Right>    cursor one word right

<LeftMouse>  cursor at mouse click

Reference: :help ex-edit-index

How to know if .keyup() is a character key (jQuery)

I never liked the key code validation. My approach was to see if the input have text (any character), confirming that the user is entering text and no other characters

_x000D_
_x000D_
$('#input').on('keyup', function() {_x000D_
    var words = $(this).val();_x000D_
    // if input is empty, remove the word count data and return_x000D_
    if(!words.length) {_x000D_
        $(this).removeData('wcount');_x000D_
        return true;_x000D_
    }_x000D_
    // if word count data equals the count of the input, return_x000D_
    if(typeof $(this).data('wcount') !== "undefined" && ($(this).data('wcount') == words.length)){_x000D_
        return true;_x000D_
    }_x000D_
    // update or initialize the word count data_x000D_
    $(this).data('wcount', words.length);_x000D_
    console.log('user tiped ' + words);_x000D_
    // do you stuff..._x000D_
});
_x000D_
<html lang="en">_x000D_
  <head>_x000D_
  <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
  </head>_x000D_
  <body>_x000D_
  <input type="text" name="input" id="input">_x000D_
  </body>_x000D_
</html>
_x000D_
_x000D_
_x000D_

Associative arrays in Shell scripts

Adding another option, if jq is available:

export NAMES="{
  \"Mary\":\"100\",
  \"John\":\"200\",
  \"Mary\":\"50\",
  \"John\":\"300\",
  \"Paul\":\"100\",
  \"Paul\":\"400\",
  \"David\":\"100\"
}"
export NAME=David
echo $NAMES | jq --arg v "$NAME" '.[$v]' | tr -d '"' 

How can I prevent a window from being resized with tkinter?

This is a variant of an existing solution already provided above:

import tkinter as tk

root = tk.Tk()
root.resizable(0, 0)
root.mainloop()

The advantage is that you type less.

How to get a key in a JavaScript object by its value?

Here is my solution first:

For example, I suppose that we have an object that contains three value pairs:

function findKey(object, value) {

    for (let key in object)
        if (object[key] === value) return key;

    return "key is not found";
}

const object = { id_1: "apple", id_2: "pear", id_3: "peach" };

console.log(findKey(object, "pear"));
//expected output: id_2

We can simply write a findKey(array, value) that takes two parameters which are an object and the value of the key you are looking for. As such, this method is reusable and you do not need to manually iterate the object every time by only passing two parameters for this function.

Change the background color in a twitter bootstrap modal?

When modal appears, it will trigger event show.bs.modal before appearing. I tried at Safari 13.1.2 on MacOS 10.15.6. When show.bs.modal event triggered, the .modal-backgrop is not inserted into body yet.

So, I give up to addClass, and removeClass to .modal-backdrop dynamically.

After viewing a lot articles on the Internet, I found a code snippet. It addClass and removeClass to the body, which is the parent of .modal-backdrop, when show.bs.modal and hide.bs.modal events triggered.

ps: I use Bootstrap 4.5.

CSS

// In order to addClass/removeClass on the `body`. The parent of `.modal-backdrop`
.no-modal-bg .modal-backdrop {
    background: none;
}

Javascript

$('#myModalId').on('show.bs.modal', function(e) {
     $('body').addClass('no-modal-bg');
}).on('hidden.bs.modal', function(e) {
     // 'hide.bs.modal' or 'hidden.bs.modal', depends on your needs.
     $('body').removeClass('no-modal-bg');
});

References

  1. The code snippet after google
  2. Bootstrap 4.5, modal, #events
  3. Bootstrap 4.5 documents

How to get the absolute path to the public_html folder?

something I found today, after reading this question and continuing on my googlesurf:

https://docs.joomla.org/How_to_find_your_absolute_path

<?php
$path = getcwd();
echo "This Is Your Absolute Path: ";
echo $path;
?>

works for me

jQuery find events handlers registered with an object

jQuery is not letting you just simply access the events for a given element. You can access them using undocumented internal method

$._data(element, "events")

But it still won't give you all the events, to be precise won't show you events assigned with

$([selector|element]).on()

These events are stored inside document, so you can fetch them by browsing through

$._data(document, "events")

but that is hard work, as there are events for whole webpage.

Tom G above created function that filters document for only events of given element and merges output of both methods, but it had a flaw of duplicating events in the output (and effectively on the element's jQuery internal event list messing with your application). I fixed that flaw and you can find the code below. Just paste it into your dev console or into your app code and execute it when needed to get nice list of all events for given element.

What is important to notice, element is actually HTMLElement, not jQuery object.

function getEvents(element) {
    var elemEvents = $._data(element, "events");
    var allDocEvnts = $._data(document, "events");
    function equalEvents(evt1, evt2)
    {
        return evt1.guid === evt2.guid;
    }

    for(var evntType in allDocEvnts) {
        if(allDocEvnts.hasOwnProperty(evntType)) {
            var evts = allDocEvnts[evntType];
            for(var i = 0; i < evts.length; i++) {
                if($(element).is(evts[i].selector)) {
                    if(elemEvents == null) {
                        elemEvents = {};
                    }
                    if(!elemEvents.hasOwnProperty(evntType)) {
                        elemEvents[evntType] = [];
                    }
                    if(!elemEvents[evntType].some(function(evt) { return equalEvents(evt, evts[i]); })) {
                        elemEvents[evntType].push(evts[i]);
                    }
                }
            }
        }
    }
    return elemEvents;
}

linking jquery in html

Seeing the answers I have nothing else to add but one more thing:

in your test.html file you have written

link rel="stylesheet" type="css/text" href="test.css"/

see where you have written

type="css/text"

there you need to change into

type="text/css"

so it will look like that

link rel="stylesheet" type="text/css" href="test.css"/

and in this case the CSS file will be linked to HTML file

Pandas: Looking up the list of sheets in an excel file

This is the fastest way I have found, inspired by @divingTobi's answer. All The answers based on xlrd, openpyxl or pandas are slow for me, as they all load the whole file first.

from zipfile import ZipFile
from bs4 import BeautifulSoup  # you also need to install "lxml" for the XML parser

with ZipFile(file) as zipped_file:
    summary = zipped_file.open(r'xl/workbook.xml').read()
soup = BeautifulSoup(summary, "xml")
sheets = [sheet.get("name") for sheet in soup.find_all("sheet")]

How to define an enumerated type (enum) in C?

As written, there's nothing wrong with your code. Are you sure you haven't done something like

int strategy;
...
enum {RANDOM, IMMEDIATE, SEARCH} strategy;

What lines do the error messages point to? When it says "previous declaration of 'strategy' was here", what's "here" and what does it show?

How to complete the RUNAS command in one line

The runas command does not allow a password on its command line. This is by design (and also the reason you cannot pipe a password to it as input). Raymond Chen says it nicely:

The RunAs program demands that you type the password manually. Why doesn't it accept a password on the command line?

This was a conscious decision. If it were possible to pass the password on the command line, people would start embedding passwords into batch files and logon scripts, which is laughably insecure.

In other words, the feature is missing to remove the temptation to use the feature insecurely.

Truncating a table in a stored procedure

try the below code

execute immediate 'truncate table tablename' ;

Get the second highest value in a MySQL table

for 2nd heightest salary

 select max(salary) from salary where salary not in (select top 1 salary from salary order by salary desc)

for 3rd heightest salary

 select max(salary) from salary where salary not in (select top 2 salary from salary order by salary desc)

and so on......

Recursively look for files with a specific extension

find $directory -type f -name "*.in"

is a bit shorter than that whole thing (and safer - deals with whitespace in filenames and directory names).

Your script is probably failing for entries that don't have a . in their name, making $extension empty.

PHP - Get key name of array value

if you need to return an array elements with same value, use array_keys() function

$array = array('red' => 1, 'blue' => 1, 'green' => 2);
print_r(array_keys($array, 1));

Interesting 'takes exactly 1 argument (2 given)' Python error

Summary (Some examples of how to define methods in classes in python)

#!/usr/bin/env python   # (if running from bash)

class Class1(object):

    def A(self, arg1):
        print arg1
        # this method requires an instance of Class1   
        # can access self.variable_name, and other methods in Class1

    @classmethod
    def B(cls, arg1):
        cls.C(arg1)
        # can access methods B and C in Class1 

    @staticmethod
    def C(arg1):
        print arg1
        # can access methods B and C in Class1 
        # (i.e. via Class1.B(...) and Class1.C(...))

Example

my_obj=Class1()

my_obj.A("1")
# Class1.A("2") # TypeError: method A() must be called with Class1 instance

my_obj.B("3")
Class1.B("4")
my_obj.C("5")
Class1.C("6")`

Random number generator only generating one random number

Every time you execute

Random random = new Random (15);

It does not matter if you execute it millions of times, you will always use the same seed.

If you use

Random random = new Random ();

You get different random number sequence, if a hacker guesses the seed and your algorithm is related to the security of your system - your algorithm is broken. I you execute mult. In this constructor the seed is specified by the system clock and if several instances are created in a very short period of time (milliseconds) it is possible that they may have the same seed.

If you need safe random numbers you must use the class

System.Security.Cryptography.RNGCryptoServiceProvider

public static int Next(int min, int max)
{
    if(min >= max)
    {
        throw new ArgumentException("Min value is greater or equals than Max value.");
    }
    byte[] intBytes = new byte[4];
    using(RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider())
    {
        rng.GetNonZeroBytes(intBytes);
    }
    return  min +  Math.Abs(BitConverter.ToInt32(intBytes, 0)) % (max - min + 1);
}

Usage:

int randomNumber = Next(1,100);

How to fix syntax error, unexpected T_IF error in php?

add semi-colon the line before:

$total_pages = ceil($total_result / $per_page);

JavaScript: Create and save file

A very minor improvement of the code by Awesomeness01 (no need for anchor tag) with addition as suggested by trueimage (support for IE):

// Function to download data to a file
function download(data, filename, type) {
    var file = new Blob([data], {type: type});
    if (window.navigator.msSaveOrOpenBlob) // IE10+
        window.navigator.msSaveOrOpenBlob(file, filename);
    else { // Others
        var a = document.createElement("a"),
                url = URL.createObjectURL(file);
        a.href = url;
        a.download = filename;
        document.body.appendChild(a);
        a.click();
        setTimeout(function() {
            document.body.removeChild(a);
            window.URL.revokeObjectURL(url);  
        }, 0); 
    }
}

Tested to be working properly in Chrome, FireFox and IE10.

In Safari, the data gets opened in a new tab and one would have to manually save this file.

Convert .pfx to .cer

If you're working in PowerShell you can use something like the following, given a pfx file InputBundle.pfx, to produce a DER encoded (binary) certificate file OutputCert.der:

Get-PfxCertificate -FilePath InputBundle.pfx | 
Export-Certificate -FilePath OutputCert.der -Type CERT

Newline added for clarity, but you can of course have this all on a single line.

If you need the certificate in ASCII/Base64 encoded PEM format, you can take extra steps to do so as documented elsewhere, such as here: https://superuser.com/questions/351548/windows-integrated-utility-to-convert-der-to-pem

If you need to export to a different format than DER encoded, you can change the -Type parameter for Export-Certificate to use the types supported by .NET, as seen in help Export-Certificate -Detailed:

-Type <CertType>
    Specifies the type of output file for the certificate export as follows. 
     -- SST: A Microsoft serialized certificate store (.sst) file format which can contain one or more certificates. This is the default value for multiple certificates. 
     -- CERT: A .cer file format which contains a single DER-encoded certificate. This is the default value for one certificate. 
     -- P7B: A PKCS#7 file format which can contain one or more certificates.

Getting the base url of the website and globally passing it to twig in Symfony 2

Also for js/css/image urls there's handy function asset()

<img src="{{ asset('image/logo.png') }}"/>

This creates an absolute url starting with /.

Perform Segue programmatically and pass parameters to the destination view

Old question but here's the code on how to do what you are asking. In this case I am passing data from a selected cell in a table view to another view controller.

in the .h file of the trget view:

@property(weak, nonatomic)  NSObject* dataModel;

in the .m file:

@synthesize dataModel;

dataModel can be string, int, or like in this case it's a model that contains many items

- (void)someMethod {
     [self performSegueWithIdentifier:@"loginMainSegue" sender:self];
 }

OR...

- (void)someMethod {
    UIViewController *myController = [self.storyboard instantiateViewControllerWithIdentifier:@"HomeController"];
    [self.navigationController pushViewController: myController animated:YES];
}

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    if([segue.identifier isEqualToString:@"storyDetailsSegway"]) {
        UITableViewCell *cell = (UITableViewCell *) sender;
        NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];
        NSDictionary *storiesDict =[topStories objectAtIndex:[indexPath row]];
        StoryModel *storyModel = [[StoryModel alloc] init];
        storyModel = storiesDict;
        StoryDetails *controller = (StoryDetails *)segue.destinationViewController;
        controller.dataModel= storyModel;
    }
}

Creating a very simple 1 username/password login in php

Firstly, you need to put session_start(); before any output to the browser, normally at the top of the page. Have a look at the manual.

Second, this won't affect your results, but these lines aren't being used anywhere and should be removed:

$usr = "admin";
$psw = "password";
$username = '$_POST[username]';
$password = '$_POST[password]';

...and the last two lines there wouldn't work, you need to put the quotes inside the square brackets:

$username = $_POST['username'];

If you put session_start() at the top of your page (i.e. before the <html> tag etc), this should work fine.

Clearing my form inputs after submission

You can use HTMLFormElement.prototype.reset according to MDN

document.getElementById("myForm").reset();

"Initializing" variables in python?

def grade(inlist):
    grade_1, grade_2, grade_3, average =inlist
    print (grade_1)
    print (grade_2)

mark=[1,2,3,4]
grade(mark)

How can I check the size of a file in a Windows batch script?

Another example

  FOR %I in (file1.txt) do @ECHO %~zI

What is the meaning of "$" sign in JavaScript

That is most likely jQuery code (more precisely, JavaScript using the jQuery library).

The $ represents the jQuery Function, and is actually a shorthand alias for jQuery. (Unlike in most languages, the $ symbol is not reserved, and may be used as a variable name.) It is typically used as a selector (i.e. a function that returns a set of elements found in the DOM).

JSP tricks to make templating easier?

Based on the same basic idea as in @Will Hartung's answer, here is my magic one-tag extensible template engine. It even includes documentation and an example :-)

WEB-INF/tags/block.tag:

<%--
    The block tag implements a basic but useful extensible template system.

    A base template consists of a block tag without a 'template' attribute.
    The template body is specified in a standard jsp:body tag, which can
    contain EL, JSTL tags, nested block tags and other custom tags, but
    cannot contain scriptlets (scriptlets are allowed in the template file,
    but only outside of the body and attribute tags). Templates can be
    full-page templates, or smaller blocks of markup included within a page.

    The template is customizable by referencing named attributes within
    the body (via EL). Attribute values can then be set either as attributes
    of the block tag element itself (convenient for short values), or by
    using nested jsp:attribute elements (better for entire blocks of markup).

    Rendering a template block or extending it in a child template is then
    just a matter of invoking the block tag with the 'template' attribute set
    to the desired template name, and overriding template-specific attributes
    as necessary to customize it.

    Attribute values set when rendering a tag override those set in the template
    definition, which override those set in its parent template definition, etc.
    The attributes that are set in the base template are thus effectively used
    as defaults. Attributes that are not set anywhere are treated as empty.

    Internally, attributes are passed from child to parent via request-scope
    attributes, which are removed when rendering is complete.

    Here's a contrived example:

    ====== WEB-INF/tags/block.tag (the template engine tag)

    <the file you're looking at right now>

    ====== WEB-INF/templates/base.jsp (base template)

    <%@ page trimDirectiveWhitespaces="true" %>
    <%@ taglib prefix="t" tagdir="/WEB-INF/tags" %>
    <t:block>
        <jsp:attribute name="title">Template Page</jsp:attribute>
        <jsp:attribute name="style">
            .footer { font-size: smaller; color: #aaa; }
            .content { margin: 2em; color: #009; }
            ${moreStyle}
        </jsp:attribute>
        <jsp:attribute name="footer">
            <div class="footer">
                Powered by the block tag
            </div>
        </jsp:attribute>
        <jsp:body>
            <html>
                <head>
                    <title>${title}</title>
                    <style>
                        ${style}
                    </style>
                </head>
                <body>
                    <h1>${title}</h1>
                    <div class="content">
                        ${content}
                    </div>
                    ${footer}
                </body>
            </html>
        </jsp:body>
    </t:block>

    ====== WEB-INF/templates/history.jsp (child template)

    <%@ page trimDirectiveWhitespaces="true" %>
    <%@ taglib prefix="t" tagdir="/WEB-INF/tags" %>
    <t:block template="base" title="History Lesson">
        <jsp:attribute name="content" trim="false">
            <p>${shooter} shot first!</p>
        </jsp:attribute>
    </t:block>

    ====== history-1977.jsp (a page using child template)

    <%@ page trimDirectiveWhitespaces="true" %>
    <%@ taglib prefix="t" tagdir="/WEB-INF/tags" %>
    <t:block template="history" shooter="Han" />

    ====== history-1997.jsp (a page using child template)

    <%@ page trimDirectiveWhitespaces="true" %>
    <%@ taglib prefix="t" tagdir="/WEB-INF/tags" %>
    <t:block template="history" title="Revised History Lesson">
        <jsp:attribute name="moreStyle">.revised { font-style: italic; }</jsp:attribute>
        <jsp:attribute name="shooter"><span class="revised">Greedo</span></jsp:attribute>
    </t:block>

--%>

<%@ tag trimDirectiveWhitespaces="true" %>
<%@ tag import="java.util.HashSet, java.util.Map, java.util.Map.Entry" %>
<%@ tag dynamic-attributes="dynattributes" %>
<%@ attribute name="template" %>
<%
    // get template name (adding default .jsp extension if it does not contain
    // any '.', and /WEB-INF/templates/ prefix if it does not start with a '/')
    String template = (String)jspContext.getAttribute("template");
    if (template != null) {
        if (!template.contains("."))
            template += ".jsp";
        if (!template.startsWith("/"))
            template = "/WEB-INF/templates/" + template;
    }
    // copy dynamic attributes into request scope so they can be accessed from included template page
    // (child is processed before parent template, so only set previously undefined attributes)
    Map<String, String> dynattributes = (Map<String, String>)jspContext.getAttribute("dynattributes");
    HashSet<String> addedAttributes = new HashSet<String>();
    for (Map.Entry<String, String> e : dynattributes.entrySet()) {
        if (jspContext.getAttribute(e.getKey(), PageContext.REQUEST_SCOPE) == null) {
            jspContext.setAttribute(e.getKey(), e.getValue(), PageContext.REQUEST_SCOPE);
            addedAttributes.add(e.getKey());
        }
    }
%>

<% if (template == null) { // this is the base template itself, so render it %>
    <jsp:doBody/>
<% } else { // this is a page using the template, so include the template instead %>
    <jsp:include page="<%= template %>" />
<% } %>

<%
    // clean up the added attributes to prevent side effect outside the current tag
    for (String key : addedAttributes) {
        jspContext.removeAttribute(key, PageContext.REQUEST_SCOPE);
    }
%>

Convert CString to const char*

If your CString is Unicode, you'll need to do a conversion to multi-byte characters. Fortunately there is a version of CString which will do this automatically.

CString unicodestr = _T("Testing");
CStringA charstr(unicodestr);
DoMyStuff((const char *) charstr);

Horizontal Scroll Table in Bootstrap/CSS

You can also check for bootstrap datatable plugin as well for above issue.

It will have a large column table scrollable feature with lot of other options

$(document).ready(function() {
    $('#example').dataTable( {
        "scrollX": true
    } );
} );

for more info with example please check out this link

Python: URLError: <urlopen error [Errno 10060]

Answer (Basic is advance!):

Error: 10060 Adding a timeout parameter to request solved the issue for me.

Example 1

import urllib
import urllib2
g = "http://www.google.com/"
read = urllib2.urlopen(g, timeout=20)

Example 2

A similar error also occurred while I was making a GET request. Again, passing a timeout parameter solved the 10060 Error.

response = requests.get(param_url, timeout=20)

What is SYSNAME data type in SQL Server?

Another use case is when using the SQL Server 2016+ functionality of AT TIME ZONE

The below statement will return a date converted to GMT

SELECT 
CONVERT(DATETIME, SWITCHOFFSET([ColumnA], DATEPART(TZOFFSET, [ColumnA] AT TIME ZONE 'GMT Standard Time')))

If you want to pass the time zone as a variable, say:

SELECT 
CONVERT(DATETIME, SWITCHOFFSET([ColumnA], DATEPART(TZOFFSET, [ColumnA] AT TIME ZONE @TimeZone)))

then that variable needs to be of the type sysname (declaring it as varchar will cause an error).

What exactly are DLL files, and how do they work?

DLLs (dynamic link libraries) and SLs (shared libraries, equivalent under UNIX) are just libraries of executable code which can be dynamically linked into an executable at load time.

Static libraries are inserted into an executable at compile time and are fixed from that point. They increase the size of the executable and cannot be shared.

Dynamic libraries have the following advantages:

1/ They are loaded at run time rather than compile time so they can be updated independently of the executable (all those fancy windows and dialog boxes you see in Windows come from DLLs so the look-and-feel of your application can change without you having to rewrite it).

2/ Because they're independent, the code can be shared across multiple executables - this saves memory since, if you're running 100 apps with a single DLL, there may only be one copy of the DLL in memory.

Their main disadvantage is advantage #1 - having DLLs change independent your application may cause your application to stop working or start behaving in a bizarre manner. DLL versioning tend not to be managed very well under Windows and this leads to the quaintly-named "DLL Hell".

How can I remove duplicate rows?

DELETE LU 
FROM   (SELECT *, 
               Row_number() 
                 OVER ( 
                   partition BY col1, col1, col3 
                   ORDER BY rowid DESC) [Row] 
        FROM   mytable) LU 
WHERE  [row] > 1 

Trying to embed newline in a variable in bash

there is no need to use for cycle

you can benefit from bash parameter expansion functions:

var="a b c"; 
var=${var// /\\n}; 
echo -e $var
a
b
c

or just use tr:

var="a b c"
echo $var | tr " " "\n"
a
b
c

How to change the bootstrap primary color?

The correct way to change the default primary colour in Bootstrap 4.x using SASS, or any other colours like secondary, success and so on.

Create the following SASS file and import Bootstrap SASS as indicated:

// (Required) Import Bootstrap
@import "bootstrap/functions";
@import "bootstrap/variables";
@import "bootstrap/mixins";

$primary: blue;
$secondary: green;
$my-color: red;

$theme-colors: (
  primary: $primary,
  secondary: $secondary,
  my-color: $my-color
);

// Add below your SASS or CSS code

// (Required) Import Bootstrap
@import "bootstrap/bootstrap";

Link to all Visual Studio $ variables

To add to the other answers, note that property sheets can be configured for the project, creating custom project-specific parameters.

To access or create them navigate to(at least in Visual Studio 2013) View -> Other Windows -> Property Manager. You can also find them in the source folder as .prop files

Disable Laravel's Eloquent timestamps

In case you want to remove timestamps from existing model, as mentioned before, place this in your Model:

public $timestamps = false;

Also create a migration with following code in the up() method and run it:

Schema::table('your_model_table', function (Blueprint $table) {
    $table->dropTimestamps();
});

You can use $table->timestamps() in your down() method to allow rolling back.

How can I check whether a numpy array is empty or not?

You can always take a look at the .size attribute. It is defined as an integer, and is zero (0) when there are no elements in the array:

import numpy as np
a = np.array([])

if a.size == 0:
    # Do something when `a` is empty

Ignore Duplicates and Create New List of Unique Values in Excel

Find here mentioned above formula with error control

=IFERROR(INDEX($B$2:$B$9, MATCH(0,COUNTIF($D$1:D1, $B$2:$B$9), 0)),"") 

where: (B2:B9 is the column data which you want to extract the unique values, D1 is the above cell where your formula is located)

package R does not exist

I just ran into this error while using Bazel to build an Android app:

error: package R does not exist
                + mContext.getString(R.string.common_string),
                                      ^
Target //libraries/common:common_paidRelease failed to build
Use --verbose_failures to see the command lines of failed build steps.

Ensure that your android_library/android_binary is using an AndroidManifest.xml with the correct package= attribute, and if you're using the custom_package attribute on android_library or android_binary, ensure that it is spelled out correctly.

Origin is not allowed by Access-Control-Allow-Origin

If you have an ASP.NET / ASP.NET MVC application, you can include this header via the Web.config file:

<system.webServer>
  ...

    <httpProtocol>
        <customHeaders>
            <!-- Enable Cross Domain AJAX calls -->
            <remove name="Access-Control-Allow-Origin" />
            <add name="Access-Control-Allow-Origin" value="*" />
        </customHeaders>
    </httpProtocol>
</system.webServer>

how to kill the tty in unix

You can run:

ps -ft pts/6 -t pts/9 -t pts/10

This would produce an output similar to:

UID        PID  PPID  C STIME TTY          TIME CMD
Vidya      772  2701  0 15:26 pts/6    00:00:00 bash
Vidya      773  2701  0 16:26 pts/9    00:00:00 bash
Vidya      774  2701  0 17:26 pts/10   00:00:00 bash

Grab the PID from the result.

Use the PIDs to kill the processes:

kill <PID1> <PID2> <PID3> ...

For the above example:

kill 772 773 774

If the process doesn't gracefully terminate, just as a last option you can forcefully kill by sending a SIGKILL

kill -9 <PID>

Python "SyntaxError: Non-ASCII character '\xe2' in file"

After about a half hour of looking through stack overflow, It dawned on me that if the use of a single quote " ' " in a comment will through the error:

SyntaxError: Non-ASCII character '\xe2' in file

After looking at the traceback i was able to locate the single quote used in my comment.

How can we programmatically detect which iOS version is device running on?

I know I am too late to answer this question. I am not sure does my method still working on low iOS versions (< 5.0):

NSString *platform = [UIDevice currentDevice].model;

NSLog(@"[UIDevice currentDevice].model: %@",platform);
NSLog(@"[UIDevice currentDevice].description: %@",[UIDevice currentDevice].description);
NSLog(@"[UIDevice currentDevice].localizedModel: %@",[UIDevice currentDevice].localizedModel);
NSLog(@"[UIDevice currentDevice].name: %@",[UIDevice currentDevice].name);
NSLog(@"[UIDevice currentDevice].systemVersion: %@",[UIDevice currentDevice].systemVersion);
NSLog(@"[UIDevice currentDevice].systemName: %@",[UIDevice currentDevice].systemName);

You can get these results:

[UIDevice currentDevice].model: iPhone
[UIDevice currentDevice].description: <UIDevice: 0x1cd75c70>
[UIDevice currentDevice].localizedModel: iPhone
[UIDevice currentDevice].name: Someones-iPhone002
[UIDevice currentDevice].systemVersion: 6.1.3
[UIDevice currentDevice].systemName: iPhone OS

scp copy directory to another server with private key auth

The command looks quite fine. Could you try to run -v (verbose mode) and then we can figure out what it is wrong on the authentication?

Also as mention in the other answer, maybe could be this issue - that you need to convert the keys (answered already here): How to convert SSH keypairs generated using PuttyGen(Windows) into key-pairs used by ssh-agent and KeyChain(Linux) OR http://winscp.net/eng/docs/ui_puttygen (depending what you need)

What does "for" attribute do in HTML <label> tag?

The for attribute of the <label> tag should be equal to the id attribute of the related element to bind them together.

validate a dropdownlist in asp.net mvc

There is an overload with 3 arguments. Html.DropdownList(name, selectList, optionLabel) Update: there was a typo in the below code snippet.

@Html.DropDownList("Cat", new SelectList(ViewBag.Categories,"ID", "CategoryName"), "-Select Category-")

For the validator use

@Html.ValidationMessage("Cat")

How to reverse a singly linked list using only two pointers?

Just for fun (although tail recursion optimization should stop it eating all the stack):


Node* reverse (Node *root, Node *end) {

    Node *next = root->next;
    root->next = end;

    return (next ? reverse(next, root) : root);
}

root = reverse(root, NULL);

Remove all the children DOM elements in div

In Dojo 1.7 or newer, use domConstruct.empty(String|DomNode):

require(["dojo/dom-construct"], function(domConstruct){
  // Empty node's children byId:
  domConstruct.empty("someId");
});

In older Dojo, use dojo.empty(String|DomNode) (deprecated at Dojo 1.8):

dojo.empty( id or DOM node );

Each of these empty methods safely removes all children of the node.

What is the difference between <section> and <div>?

In the HTML5 standard, the <section> element is defined as a block of related elements.

The <div> element is defined as a block of children elements.

AngularJS : Difference between the $observe and $watch methods

$observe() is a method on the Attributes object, and as such, it can only be used to observe/watch the value change of a DOM attribute. It is only used/called inside directives. Use $observe when you need to observe/watch a DOM attribute that contains interpolation (i.e., {{}}'s).
E.g., attr1="Name: {{name}}", then in a directive: attrs.$observe('attr1', ...).
(If you try scope.$watch(attrs.attr1, ...) it won't work because of the {{}}s -- you'll get undefined.) Use $watch for everything else.

$watch() is more complicated. It can observe/watch an "expression", where the expression can be either a function or a string. If the expression is a string, it is $parse'd (i.e., evaluated as an Angular expression) into a function. (It is this function that is called every digest cycle.) The string expression can not contain {{}}'s. $watch is a method on the Scope object, so it can be used/called wherever you have access to a scope object, hence in

  • a controller -- any controller -- one created via ng-view, ng-controller, or a directive controller
  • a linking function in a directive, since this has access to a scope as well

Because strings are evaluated as Angular expressions, $watch is often used when you want to observe/watch a model/scope property. E.g., attr1="myModel.some_prop", then in a controller or link function: scope.$watch('myModel.some_prop', ...) or scope.$watch(attrs.attr1, ...) (or scope.$watch(attrs['attr1'], ...)).
(If you try attrs.$observe('attr1') you'll get the string myModel.some_prop, which is probably not what you want.)

As discussed in comments on @PrimosK's answer, all $observes and $watches are checked every digest cycle.

Directives with isolate scopes are more complicated. If the '@' syntax is used, you can $observe or $watch a DOM attribute that contains interpolation (i.e., {{}}'s). (The reason it works with $watch is because the '@' syntax does the interpolation for us, hence $watch sees a string without {{}}'s.) To make it easier to remember which to use when, I suggest using $observe for this case also.

To help test all of this, I wrote a Plunker that defines two directives. One (d1) does not create a new scope, the other (d2) creates an isolate scope. Each directive has the same six attributes. Each attribute is both $observe'd and $watch'ed.

<div d1 attr1="{{prop1}}-test" attr2="prop2" attr3="33" attr4="'a_string'"
        attr5="a_string" attr6="{{1+aNumber}}"></div>

Look at the console log to see the differences between $observe and $watch in the linking function. Then click the link and see which $observes and $watches are triggered by the property changes made by the click handler.

Notice that when the link function runs, any attributes that contain {{}}'s are not evaluated yet (so if you try to examine the attributes, you'll get undefined). The only way to see the interpolated values is to use $observe (or $watch if using an isolate scope with '@'). Therefore, getting the values of these attributes is an asynchronous operation. (And this is why we need the $observe and $watch functions.)

Sometimes you don't need $observe or $watch. E.g., if your attribute contains a number or a boolean (not a string), just evaluate it once: attr1="22", then in, say, your linking function: var count = scope.$eval(attrs.attr1). If it is just a constant string – attr1="my string" – then just use attrs.attr1 in your directive (no need for $eval()).

See also Vojta's google group post about $watch expressions.

Python Hexadecimal

Use the format() function with a '02x' format.

>>> format(255, '02x')
'ff'
>>> format(2, '02x')
'02'

The 02 part tells format() to use at least 2 digits and to use zeros to pad it to length, x means lower-case hexadecimal.

The Format Specification Mini Language also gives you X for uppercase hex output, and you can prefix the field width with # to include a 0x or 0X prefix (depending on wether you used x or X as the formatter). Just take into account that you need to adjust the field width to allow for those extra 2 characters:

>>> format(255, '02X')
'FF'
>>> format(255, '#04x')
'0xff'
>>> format(255, '#04X')
'0XFF'

No resource found that matches the given name '@style/ Theme.Holo.Light.DarkActionBar'

Do this:

"android:style/Theme.Holo.Light.DarkActionBar"

You missed the android keyword before style. This denotes that it is an inbuilt style for Android.

Run php function on button click

You are trying to call a javascript function. If you want to call a PHP function, you have to use for example a form:

    <form action="action_page.php">
       First name:<br>
       <input type="text" name="firstname" value="Mickey">
       <br>
       Last name:<br>
       <input type="text" name="lastname" value="Mouse">
       <br><br>
       <input type="submit" value="Submit">
     </form> 

(Original Code from: http://www.w3schools.com/html/html_forms.asp)

So if you want do do a asynchron call, you could use 'Ajax' - and yeah, that's the Javascript-Way. But I think, that my code example is enough for this time :)

Docker: Multiple Dockerfiles in project

In newer versions(>=1.8.0) of docker, you can do this

docker build -f Dockerfile.db .
docker build -f Dockerfile.web .

A big save.

EDIT: update versions per raksja's comment

EDIT: comment from @vsevolod: it's possible to get syntax highlighting in VS code by giving files .Dockerfile extension(instead of name) e.g. Prod.Dockerfile, Test.Dockerfile etc.

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

The URL file://[servername]/[sharename] should open an explorer window to the shared folder on the network.

How to get selected option using Selenium WebDriver with Java

Completing the answer:

String selectedOption = new Select(driver.findElement(By.xpath("Type the xpath of the drop-down element"))).getFirstSelectedOption().getText();

Assert.assertEquals("Please select any option...", selectedOption);

How to set the project name/group/version, plus {source,target} compatibility in the same file?

Apparently this would be possible in settings.gradle with something like this.

rootProject.name = 'someName'
gradle.rootProject {
    it.sourceCompatibility = '1.7'
}

I recently received advice that a project property can be set by using a closure which will be called later when the Project is available.

How to create a database from shell command?

The ist and 2nd answer are good but if anybody is looking for having a script or If you want dynamic i.e (db/username/password in variable) then here:

#!/bin/bash



DB="mydb"
USER="user1"
PASS="pass_bla"

mysql -uroot -prootpassword -e "CREATE DATABASE $DB CHARACTER SET utf8 COLLATE utf8_general_ci";
mysql -uroot -prootpassword -e "CREATE USER $USER@'127.0.0.1' IDENTIFIED BY '$PASS'";
mysql -uroot -prootpassword -e "GRANT SELECT, INSERT, UPDATE ON $DB.* TO '$USER'@'127.0.0.1'";

remove first element from array and return the array minus the first element

You can use array.slice(0,1) // First index is removed and array is returned.

Does height and width not apply to span?

spans are by default displayed inline, which means they don't have a height and width.

Try adding a display: block to your span.

JavaFX Panel inside Panel auto resizing

If you are using Scene Builder, you will see at the right an accordion panel which normally has got three options ("Properties", "Layout" and "Code"). In the second one ("Layout"), you will see an option called "[parent layout] Constraints" (in your case "AnchorPane Constrainsts").

You should put "0" in the four sides of the element wich represents the parent layout.

"Call to undefined function mysql_connect()" after upgrade to php-7

From the PHP Manual:

Warning This extension was deprecated in PHP 5.5.0, and it was removed in PHP 7.0.0. Instead, the MySQLi or PDO_MySQL extension should be used. See also MySQL: choosing an API guide. Alternatives to this function include:

mysqli_connect()

PDO::__construct()

use MySQLi or PDO

<?php
$con = mysqli_connect('localhost', 'username', 'password', 'database');

How to automatically import data from uploaded CSV or XLS file into Google Sheets

In case anyone would be searching - I created utility for automated import of xlsx files into google spreadsheet: xls2sheets. One can do it automatically via setting up the cronjob for ./cmd/sheets-refresh, readme describes it all. Hope that would be of use.

Use of ~ (tilde) in R programming Language

R defines a ~ (tilde) operator for use in formulas. Formulas have all sorts of uses, but perhaps the most common is for regression:

library(datasets)
lm( myFormula, data=iris)

help("~") or help("formula") will teach you more.

@Spacedman has covered the basics. Let's discuss how it works.

First, being an operator, note that it is essentially a shortcut to a function (with two arguments):

> `~`(lhs,rhs)
lhs ~ rhs
> lhs ~ rhs
lhs ~ rhs

That can be helpful to know for use in e.g. apply family commands.

Second, you can manipulate the formula as text:

oldform <- as.character(myFormula) # Get components
myFormula <- as.formula( paste( oldform[2], "Sepal.Length", sep="~" ) )

Third, you can manipulate it as a list:

myFormula[[2]]
myFormula[[3]]

Finally, there are some helpful tricks with formulae (see help("formula") for more):

myFormula <- Species ~ . 

For example, the version above is the same as the original version, since the dot means "all variables not yet used." This looks at the data.frame you use in your eventual model call, sees which variables exist in the data.frame but aren't explicitly mentioned in your formula, and replaces the dot with those missing variables.

Check if input is integer type in C

I developed this logic using gets and away from scanf hassle:

void readValidateInput() {

    char str[10] = { '\0' };

    readStdin: fgets(str, 10, stdin);
    //printf("fgets is returning %s\n", str);

    int numerical = 1;
    int i = 0;

    for (i = 0; i < 10; i++) {
        //printf("Digit at str[%d] is %c\n", i, str[i]);
        //printf("numerical = %d\n", numerical);
        if (isdigit(str[i]) == 0) {
            if (str[i] == '\n')break;
            numerical = 0;
            //printf("numerical changed= %d\n", numerical);
            break;
        }
    }
    if (!numerical) {
        printf("This is not a valid number of tasks, you need to enter at least 1 task\n");
        goto readStdin;
    }
    else if (str[i] == '\n') {
        str[i] = '\0';
        numOfTasks = atoi(str);
        //printf("Captured Number of tasks from stdin is %d\n", numOfTasks);
    }
}

How to trigger click on page load?

The click handler that you are trying to trigger is most likely also attached via $(document).ready(). What is probably happening is that you are triggering the event before the handler is attached. The solution is to use setTimeout:

$("document").ready(function() {
    setTimeout(function() {
        $("ul.galleria li:first-child img").trigger('click');
    },10);
});

A delay of 10ms will cause the function to run immediately after all the $(document).ready() handlers have been called.

OR you check if the element is ready:

$("document").ready(function() {
  $("ul.galleria li:first-child img").ready(function() {
    $(this).click();
  });    
});

How to create User/Database in script for Docker Postgres

You can use this commands:

docker exec -it yournamecontainer psql -U postgres -c "CREATE DATABASE mydatabase ENCODING 'LATIN1' TEMPLATE template0 LC_COLLATE 'C' LC_CTYPE 'C';"

docker exec -it yournamecontainer psql -U postgres -c "GRANT ALL PRIVILEGES ON DATABASE postgres TO postgres;"

UITextView that expands to text using auto layout

I needed a text view that would automatically grow up until a certain maximum height, then become scrollable. Michael Link's answer worked great but I wanted to see if I could come up with something a bit simpler. Here's what I came up with:

Swift 5.3, Xcode 12

class AutoExpandingTextView: UITextView {

    private var heightConstraint: NSLayoutConstraint!

    var maxHeight: CGFloat = 100 {
        didSet {
            heightConstraint?.constant = maxHeight
        }
    }

    private var observer: NSObjectProtocol?

    override init(frame: CGRect, textContainer: NSTextContainer?) {
        super.init(frame: frame, textContainer: textContainer)
        commonInit()
    }

    required init?(coder: NSCoder) {
        super.init(coder: coder)
        commonInit()
    }

    private func commonInit() {
        heightConstraint = heightAnchor.constraint(equalToConstant: maxHeight)

        observer = NotificationCenter.default.addObserver(forName: UITextView.textDidChangeNotification, object: nil, queue: .main) { [weak self] _ in
            guard let self = self else { return }
            self.heightConstraint.isActive = self.contentSize.height > self.maxHeight
            self.isScrollEnabled = self.contentSize.height > self.maxHeight
            self.invalidateIntrinsicContentSize()
        }
    }
}


Querying DynamoDB by date

Updated Answer:

DynamoDB allows for specification of secondary indexes to aid in this sort of query. Secondary indexes can either be global, meaning that the index spans the whole table across hash keys, or local meaning that the index would exist within each hash key partition, thus requiring the hash key to also be specified when making the query.

For the use case in this question, you would want to use a global secondary index on the "CreatedAt" field.

For more on DynamoDB secondary indexes see the secondary index documentation

Original Answer:

DynamoDB does not allow indexed lookups on the range key only. The hash key is required such that the service knows which partition to look in to find the data.

You can of course perform a scan operation to filter by the date value, however this would require a full table scan, so it is not ideal.

If you need to perform an indexed lookup of records by time across multiple primary keys, DynamoDB might not be the ideal service for you to use, or you might need to utilize a separate table (either in DynamoDB or a relational store) to store item metadata that you can perform an indexed lookup against.

Youtube - downloading a playlist - youtube-dl

Your link is not a playlist.

A proper playlist URL looks like this:

https://www.youtube.com/playlist?list=PLHSdFJ8BDqEyvUUzm6R0HxawSWniP2c9K

Your URL is just the first video OF a certain playlist. It contains https://www.youtube.com/watch? instead of https://www.youtube.com/playlist?.

Pick the playlist by clicking on the title of the playlist on the right side in the list of videos and use this URL.

Execution sequence of Group By, Having and Where clause in SQL Server?

Having Clause may come prior/before the group by clause.

Example: select * FROM test_std; ROLL_NO SNAME DOB TEACH


     1 John       27-AUG-18 Wills     
     2 Knit       27-AUG-18 Prestion  
     3 Perl       27-AUG-18 Wills     
     4 Ohrm       27-AUG-18 Woods     
     5 Smith      27-AUG-18 Charmy    
     6 Jony       27-AUG-18 Wills     
       Warner     20-NOV-18 Wills     
       Marsh      12-NOV-18 Langer    
       FINCH      18-OCT-18 Langer    

9 rows selected.

select teach, count() count from test_std having count() > 1 group by TEACH ;

TEACH COUNT


Langer 2 Wills 4

How do I find out if the GPS of an Android device is enabled

Yes you can check below is the code:

public boolean isGPSEnabled (Context mContext){
    LocationManager locationManager = (LocationManager)
                mContext.getSystemService(Context.LOCATION_SERVICE);
    return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER);
}

What is the best way to iterate over multiple lists at once?

The usual way is to use zip():

for x, y in zip(a, b):
    # x is from a, y is from b

This will stop when the shorter of the two iterables a and b is exhausted. Also worth noting: itertools.izip() (Python 2 only) and itertools.izip_longest() (itertools.zip_longest() in Python 3).

Populating a database in a Laravel migration file

If you already have filled columns and have added new one or you want to fill out old column with new mock values , do this:

public function up()
{
    DB::table('foydabars')->update(
        array(
            'status' => '0'
        )
    );
}

Duplicate headers received from server

For me the issue was about a comma not in the filename but as below: -

Response.ok(streamingOutput,MediaType.APPLICATION_OCTET_STREAM_TYPE).header("content-disposition", "attachment, filename=your_file_name").build();

I accidentally put a comma after attachment. Got it resolved by replacing comma with a semicolon.

Removing all non-numeric characters from string in Python

Not sure if this is the most efficient way, but:

>>> ''.join(c for c in "abc123def456" if c.isdigit())
'123456'

The ''.join part means to combine all the resulting characters together without any characters in between. Then the rest of it is a list comprehension, where (as you can probably guess) we only take the parts of the string that match the condition isdigit.

How to scale a UIImageView proportionally?

imageView.contentMode = UIViewContentModeScaleAspectFill;
imageView.clipsToBounds = YES;

How do I properly compare strings in C?

How do I properly compare strings?

char input[40];
char check[40];
strcpy(input, "Hello"); // input assigned somehow
strcpy(check, "Hello"); // check assigned somehow

// insufficient
while (check != input)

// good
while (strcmp(check, input) != 0)
// or 
while (strcmp(check, input))

Let us dig deeper to see why check != input is not sufficient.

In C, string is a standard library specification.

A string is a contiguous sequence of characters terminated by and including the first null character.
C11 §7.1.1 1

input above is not a string. input is array 40 of char.

The contents of input can become a string.

In most cases, when an array is used in an expression, it is converted to the address of its 1st element.

The below converts check and input to their respective addresses of the first element, then those addresses are compared.

check != input   // Compare addresses, not the contents of what addresses reference

To compare strings, we need to use those addresses and then look at the data they point to.
strcmp() does the job. §7.23.4.2

int strcmp(const char *s1, const char *s2);

The strcmp function compares the string pointed to by s1 to the string pointed to by s2.

The strcmp function returns an integer greater than, equal to, or less than zero, accordingly as the string pointed to by s1 is greater than, equal to, or less than the string pointed to by s2.

Not only can code find if the strings are of the same data, but which one is greater/less when they differ.

The below is true when the string differ.

strcmp(check, input) != 0

For insight, see Creating my own strcmp() function

Can you use CSS to mirror/flip text?

You can user either

.your-class{ 
      position:absolute; 
      -moz-transform: scaleX(-1); 
      -o-transform: scaleX(-1); 
      -webkit-transform: scaleX(-1); 
      transform: scaleX(-1); 
      filter: FlipH;  
}

or

 .your-class{ 
  position:absolute;
  transform: rotate(360deg) scaleX(-1);
}

Notice that setting position to absolute is very important! If you won't set it, you will need to set display: inline-block;

Auto start node.js server on boot

This isn't something to configure in node.js at all, this is purely OS responsibility (Windows in your case). The most reliable way to achieve this is through a Windows Service.

There's this super easy module that installs a node script as a windows service, it's called node-windows (npm, github, documentation). I've used before and worked like a charm.

var Service = require('node-windows').Service;

// Create a new service object
var svc = new Service({
  name:'Hello World',
  description: 'The nodejs.org example web server.',
  script: 'C:\\path\\to\\helloworld.js'
});

// Listen for the "install" event, which indicates the
// process is available as a service.
svc.on('install',function(){
  svc.start();
});

svc.install();

p.s.

I found the thing so useful that I built an even easier to use wrapper around it (npm, github).

Installing it:

npm install -g qckwinsvc

Installing your service:

> qckwinsvc
prompt: Service name: [name for your service]
prompt: Service description: [description for it]
prompt: Node script path: [path of your node script]
Service installed

Uninstalling your service:

> qckwinsvc --uninstall
prompt: Service name: [name of your service]
prompt: Node script path: [path of your node script]
Service stopped
Service uninstalled

How do I print a double value without scientific notation using Java?

I think everyone had the right idea, but all answers were not straightforward. I can see this being a very useful piece of code. Here is a snippet of what will work:

System.out.println(String.format("%.8f", EnterYourDoubleVariableHere));

the ".8" is where you set the number of decimal places you would like to show.

I am using Eclipse and it worked no problem.

Hope this was helpful. I would appreciate any feedback!

postgresql return 0 if returned value is null

I can think of 2 ways to achieve this:

  • IFNULL():

    The IFNULL() function returns a specified value if the expression is NULL.If the expression is NOT NULL, this function returns the expression.

Syntax:

IFNULL(expression, alt_value)

Example of IFNULL() with your query:

SELECT AVG( price )
FROM(
      SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
      WHERE listing_Type = 'AARM'
        AND u_kbalikepartnumbers_id = 1000307
        AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
        AND IFNULL( price, 0 ) > ( SELECT AVG( IFNULL( price, 0 ) )* 0.50
                                     FROM ( SELECT *, cume_dist() OVER ( ORDER BY price DESC )
                                           FROM web_price_scan
                                           WHERE listing_Type='AARM'
                                             AND u_kbalikepartnumbers_id = 1000307
                                             AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
                                         ) g
                                    WHERE cume_dist < 0.50
                                  )
        AND IFNULL( price, 0 ) < ( SELECT AVG( IFNULL( price, 0 ) ) *2
                                     FROM( SELECT *, cume_dist() OVER ( ORDER BY price desc )
                                           FROM web_price_scan
                                           WHERE listing_Type='AARM'
                                             AND u_kbalikepartnumbers_id = 1000307
                                             AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
                                         ) d
                                     WHERE cume_dist < 0.50)
     )s
HAVING COUNT(*) > 5
  • COALESCE()

    The COALESCE() function returns the first non-null value in a list.

Syntax:

COALESCE(val1, val2, ...., val_n)

Example of COALESCE() with your query:

SELECT AVG( price )
FROM(
      SELECT *, cume_dist() OVER ( ORDER BY price DESC ) FROM web_price_scan
      WHERE listing_Type = 'AARM'
        AND u_kbalikepartnumbers_id = 1000307
        AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
        AND COALESCE( price, 0 ) > ( SELECT AVG( COALESCE( price, 0 ) )* 0.50
                                     FROM ( SELECT *, cume_dist() OVER ( ORDER BY price DESC )
                                           FROM web_price_scan
                                           WHERE listing_Type='AARM'
                                             AND u_kbalikepartnumbers_id = 1000307
                                             AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
                                         ) g
                                    WHERE cume_dist < 0.50
                                  )
        AND COALESCE( price, 0 ) < ( SELECT AVG( COALESCE( price, 0 ) ) *2
                                     FROM( SELECT *, cume_dist() OVER ( ORDER BY price desc )
                                           FROM web_price_scan
                                           WHERE listing_Type='AARM'
                                             AND u_kbalikepartnumbers_id = 1000307
                                             AND ( EXTRACT( DAY FROM ( NOW() - dateEnded ) ) ) * 24 < 48
                                         ) d
                                     WHERE cume_dist < 0.50)
     )s
HAVING COUNT(*) > 5

extract month from date in python

import datetime

a = '2010-01-31'

datee = datetime.datetime.strptime(a, "%Y-%m-%d")


datee.month
Out[9]: 1

datee.year
Out[10]: 2010

datee.day
Out[11]: 31

Changing the sign of a number in PHP?

function positive_number($number)
{
    if ($number < 0) {
        $number *= -1;
    }

   return $number;
}

REST API - file (ie images) processing - best practices

OP here (I am answering this question after two years, the post made by Daniel Cerecedo was not bad at a time, but the web services are developing very fast)

After three years of full-time software development (with focus also on software architecture, project management and microservice architecture) I definitely choose the second way (but with one general endpoint) as the best one.

If you have a special endpoint for images, it gives you much more power over handling those images.

We have the same REST API (Node.js) for both - mobile apps (iOS/android) and frontend (using React). This is 2017, therefore you don't want to store images locally, you want to upload them to some cloud storage (Google cloud, s3, cloudinary, ...), therefore you want some general handling over them.

Our typical flow is, that as soon as you select an image, it starts uploading on background (usually POST on /images endpoint), returning you the ID after uploading. This is really user-friendly, because user choose an image and then typically proceed with some other fields (i.e. address, name, ...), therefore when he hits "send" button, the image is usually already uploaded. He does not wait and watching the screen saying "uploading...".

The same goes for getting images. Especially thanks to mobile phones and limited mobile data, you don't want to send original images, you want to send resized images, so they do not take that much bandwidth (and to make your mobile apps faster, you often don't want to resize it at all, you want the image that fits perfectly into your view). For this reason, good apps are using something like cloudinary (or we do have our own image server for resizing).

Also, if the data are not private, then you send back to app/frontend just URL and it downloads it from cloud storage directly, which is huge saving of bandwidth and processing time for your server. In our bigger apps there are a lot of terabytes downloaded every month, you don't want to handle that directly on each of your REST API server, which is focused on CRUD operation. You want to handle that at one place (our Imageserver, which have caching etc.) or let cloud services handle all of it.


Cons : The only "cons" which you should think of is "not assigned images". User select images and continue with filling other fields, but then he says "nah" and turn off the app or tab, but meanwhile you successfully uploaded the image. This means you have uploaded an image which is not assigned anywhere.

There are several ways of handling this. The most easiest one is "I don't care", which is a relevant one, if this is not happening very often or you even have desire to store every image user send you (for any reason) and you don't want any deletion.

Another one is easy too - you have CRON and i.e. every week and you delete all unassigned images older than one week.

How to rename a file using Python

If you are Using Windows and you want to rename your 1000s of files in a folder then: You can use the below code. (Python3)

import os

path = os.chdir(input("Enter the path of the Your Image Folder :  ")) #Here put the path of your folder where your images are stored

image_name = input("Enter your Image name : ") #Here, enter the name you want your images to have

i = 0

for file in os.listdir(path):

    new_file_name = image_name+"_" + str(i) + ".jpg" #here you can change the extention of your renmamed file.
    os.rename(file,new_file_name)

    i = i + 1

input("Renamed all Images!!")

Best way to get all selected checkboxes VALUES in jQuery

You want the :checkbox:checked selector and map to create an array of the values:

var checkedValues = $('input:checkbox:checked').map(function() {
    return this.value;
}).get();

If your checkboxes have a shared class it would be faster to use that instead, eg. $('.mycheckboxes:checked'), or for a common name $('input[name="Foo"]:checked')

- Update -

If you don't need IE support then you can now make the map() call more succinct by using an arrow function:

var checkedValues = $('input:checkbox:checked').map((i, el) => el.value).get();

What is the difference between typeof and instanceof and when should one be used vs. the other?

_x000D_
_x000D_
var newObj =  new Object;//instance of Object_x000D_
var newProp = "I'm xgqfrms!" //define property_x000D_
var newFunc = function(name){//define function _x000D_
 var hello ="hello, "+ name +"!";_x000D_
 return hello;_x000D_
}_x000D_
newObj.info = newProp;// add property_x000D_
newObj.func = newFunc;// add function_x000D_
_x000D_
console.log(newObj.info);// call function_x000D_
// I'm xgqfrms!_x000D_
console.log(newObj.func("ET"));// call function_x000D_
// hello, ET!_x000D_
_x000D_
console.log(newObj instanceof Object);_x000D_
//true_x000D_
console.log(typeof(newObj));_x000D_
//"object"
_x000D_
_x000D_
_x000D_

Angular JS - angular.forEach - How to get key of the object?

The first parameter to the iterator in forEach is the value and second is the key of the object.

angular.forEach(objectToIterate, function(value, key) {
    /* do something for all key: value pairs */
});

In your example, the outer forEach is actually:

angular.forEach($scope.filters, function(filterObj , filterKey)

How to set the height of an input (text) field in CSS?

You should use font-size for controlling the height, it is widely supported amongst browsers. And in order to add spacing, you should use padding. Forexample,

.inputField{
  font-size: 30px;
  padding-top: 10px;
  padding-bottom: 10px;
}

Display a view from another controller in ASP.NET MVC

Yes, you can. Return an Action like this :

return RedirectToAction("View", "Name of Controller");

An example:

return RedirectToAction("Details/" + id.ToString(), "FullTimeEmployees");

This approach will call the GET method

Also you could pass values to action like this:

return RedirectToAction("Details/" + id.ToString(), "FullTimeEmployees", new {id = id.ToString(), viewtype = "extended" });

What does 'Unsupported major.minor version 52.0' mean, and how do I fix it?

You don't need to change the compliance level here, or rather, you should but that's not the issue.

The code compliance ensures your code is compatible with a given Java version.

For instance, if you have a code compliance targeting Java 6, you can't use Java 7's or 8's new syntax features (e.g. the diamond, the lambdas, etc. etc.).

The actual issue here is that you are trying to compile something in a Java version that seems different from the project dependencies in the classpath.

Instead, you should check the JDK/JRE you're using to build.

In Eclipse, open the project properties and check the selected JRE in the Java build path.

If you're using custom Ant (etc.) scripts, you also want to take a look there, in case the above is not sufficient per se.

List comprehension on a nested list?

This Problem can be solved without using for loop.Single line code will be sufficient for this. Using Nested Map with lambda function will also works here.

l = [['40', '20', '10', '30'], ['20', '20', '20', '20', '20', '30', '20'], ['30', '20', '30', '50', '10', '30', '20', '20', '20'], ['100', '100'], ['100', '100', '100', '100', '100'], ['100', '100', '100', '100']]

map(lambda x:map(lambda y:float(y),x),l)

And Output List would be as follows:

[[40.0, 20.0, 10.0, 30.0], [20.0, 20.0, 20.0, 20.0, 20.0, 30.0, 20.0], [30.0, 20.0, 30.0, 50.0, 10.0, 30.0, 20.0, 20.0, 20.0], [100.0, 100.0], [100.0, 100.0, 100.0, 100.0, 100.0], [100.0, 100.0, 100.0, 100.0]]

How to safely upgrade an Amazon EC2 instance from t1.micro to large?

From my experience, the way I do it is create a snapshot of your current image, then once its done you'll see it as an option when launching new instances. Simply launch it as a large instance at that point.

This is my approach if I do not want any downtime(i.e. production server) because this solution only takes a server offline only after the new one is up and running(I also use it to add new machines to my clusters by using this approach to only add new machines). If Downtime is acceptable then see Marcel Castilho's answer.

Convert JSON string to dict using Python

If you trust the data source, you can use eval to convert your string into a dictionary:

eval(your_json_format_string)

Example:

>>> x = "{'a' : 1, 'b' : True, 'c' : 'C'}"
>>> y = eval(x)

>>> print x
{'a' : 1, 'b' : True, 'c' : 'C'}
>>> print y
{'a': 1, 'c': 'C', 'b': True}

>>> print type(x), type(y)
<type 'str'> <type 'dict'>

>>> print y['a'], type(y['a'])
1 <type 'int'>

>>> print y['a'], type(y['b'])
1 <type 'bool'>

>>> print y['a'], type(y['c'])
1 <type 'str'>

Regular expression for checking if capital letters are found consecutively in a string?

Edit: 2015-10-26: thanks for the upvotes - but take a look at tchrist's answer, especially if you develop for the web or something more "international".

Oren Trutners answer isn't quite right (see sample input of "RightHerE" which must be matched but isn't)

Here is the correct solution:

(?!^.*[A-Z]{2,}.*$)^[A-Za-z]*$

edit:

(?!^.*[A-Z]{2,}.*$)  // don't match the whole expression if there are two or more consecutive uppercase letters
^[A-Za-z]*$          // match uppercase and lowercase letters

/edit

the key for the solution is a negative lookahead see: http://www.regular-expressions.info/lookaround.html

Get Current date & time with [NSDate date]

NSLocale* currentLocale = [NSLocale currentLocale];
[[NSDate date] descriptionWithLocale:currentLocale];  

or use

NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init]; 
[dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
// or @"yyyy-MM-dd hh:mm:ss a" if you prefer the time with AM/PM 
NSLog(@"%@",[dateFormatter stringFromDate:[NSDate date]]);

How to get UTF-8 working in Java webapps?

One other point that hasn't been mentioned relates to Java Servlets working with Ajax. I have situations where a web page is picking up utf-8 text from the user sending this to a JavaScript file which includes it in a URI sent to the Servlet. The Servlet queries a database, captures the result and returns it as XML to the JavaScript file which formats it and inserts the formatted response into the original web page.

In one web app I was following an early Ajax book's instructions for wrapping up the JavaScript in constructing the URI. The example in the book used the escape() method, which I discovered (the hard way) is wrong. For utf-8 you must use encodeURIComponent().

Few people seem to roll their own Ajax these days, but I thought I might as well add this.

How can I set a css border on one side only?

If you want to set 4 sides separately use:

border-width: 1px 2em 5px 0; /* top right bottom left */
border-style: solid dotted inset double;
border-color: #f00 #0f0 #00f #ff0;

How to trigger event in JavaScript?

Use jquery event call. Write the below line where you want to trigger onChange of any element.

$("#element_id").change();

element_id is the ID of the element whose onChange you want to trigger.

Avoid the use of

 element.fireEvent("onchange");

Because it has very less support. Refer this document for its support.

gcc warning" 'will be initialized after'

The order of initialization doesn’t matter. All fields are initialized in the order of their definition in their class/struct. But if the order in initialization list is different gcc/g++ generate this warning. Only change the initialization order to avoid this warning. But you can't define field using in initialization before its construct. It will be a runtime error. So you change the order of definition. Be careful and keep attention!

RESTful call in Java

If you are calling a RESTful service from a Service Provider (e.g Facebook, Twitter), you can do it with any flavour of your choice:

If you don't want to use external libraries, you can use java.net.HttpURLConnection or javax.net.ssl.HttpsURLConnection (for SSL), but that is call encapsulated in a Factory type pattern in java.net.URLConnection. To receive the result, you will have to connection.getInputStream() which returns you an InputStream. You will then have to convert your input stream to string and parse the string into it's representative object (e.g. XML, JSON, etc).

Alternatively, Apache HttpClient (version 4 is the latest). It's more stable and robust than java's default URLConnection and it supports most (if not all) HTTP protocol (as well as it can be set to Strict mode). Your response will still be in InputStream and you can use it as mentioned above.


Documentation on HttpClient: http://hc.apache.org/httpcomponents-client-ga/tutorial/html/index.html

Get only specific attributes with from Laravel Collection

this is a follow up on the patricus [answer][1] above but for nested arrays:

$topLevelFields =  ['id','status'];
$userFields = ['first_name','last_name','email','phone_number','op_city_id'];

return $onlineShoppers->map(function ($user) { 
    return collect($user)->only($topLevelFields)
                             ->merge(collect($user['user'])->only($userFields))->all();  
    })->all();

Parse an URL in JavaScript

You can use the jquery plugin http://plugins.jquery.com/url. $.url("?img_id") will return 33

ORA-01461: can bind a LONG value only for insert into a LONG column-Occurs when querying

This ORA-01461 does not occur only while inserting into a Long column. This error can occur when binding a long string for insert into a VARCHAR2 column and most commonly occurs when there is a multi byte(means single char can take more than one byte space in oracle) character conversion issue.

If the database is UTF-8 then, because of the fact that each character can take up to 3 bytes, conversion of 3 applied to check and so actually limited to use 1333 characters to insert into varchar2(4000).

Another solution would be change the datatype from varchar2(4000) to CLOB.

Insert a string at a specific index

Here is a method I wrote that behaves like all other programming languages:

_x000D_
_x000D_
String.prototype.insert = function(index, string) {
  if (index > 0) {
    return this.substring(0, index) + string + this.substr(index);
  }

  return string + this;
};

//Example of use:
var something = "How you?";
something = something.insert(3, " are");
console.log(something)
_x000D_
_x000D_
_x000D_

Reference:

Function to close the window in Tkinter

class App():
    def __init__(self):
        self.root = Tkinter.Tk()
        button = Tkinter.Button(self.root, text = 'root quit', command=self.quit)
        button.pack()
        self.root.mainloop()

    def quit(self):
        self.root.destroy()

app = App()

Joining two table entities in Spring Data JPA

This has been an old question but solution is very simple to that. If you are ever unsure about how to write criterias, joins etc in hibernate then best way is using native queries. This doesn't slow the performance and very useful. Eq. below

    @Query(nativeQuery = true, value = "your sql query")
returnTypeOfMethod methodName(arg1, arg2);

Installing mcrypt extension for PHP on OSX Mountain Lion

I tend to use Homebrew on Mac. It will install and configure all the stuff for you.
http://mxcl.github.com/homebrew/

Then you should be able to install it with brew install mcrypt php53-mcrypt and it'll Just Work (tm).

You can replace the 53 with whatever version of PHP you're using, such as php56-mcrypt or php70-mcrypt. If you're not sure, use brew search php.

Do also remember that if you are using the built in Mac PHP it's installed into /usr/bin you can see which php you are using with which php at the terminal and it'll return the path.

How to replace case-insensitive literal substrings in Java

I like smas's answer that uses replaceAll with a regular expression. If you are going to be doing the same replacement many times, it makes sense to pre-compile the regular expression once:

import java.util.regex.Pattern;

public class Test { 

    private static final Pattern fooPattern = Pattern.compile("(?i)foo");

    private static removeFoo(s){
        if (s != null) s = fooPattern.matcher(s).replaceAll("");
        return s;
    }

    public static void main(String[] args) {
        System.out.println(removeFoo("FOOBar"));
    }
}

How do I install the Nuget provider for PowerShell on a unconnected machine so I can install a nuget package from the PS command line?

MSDocs state this for your scenario:

In order to execute the first time, PackageManagement requires an internet connection to download the Nuget package provider. However, if your computer does not have an internet connection and you need to use the Nuget or PowerShellGet provider, you can download them on another computer and copy them to your target computer. Use the following steps to do this:

  1. Run Install-PackageProvider -Name NuGet -RequiredVersion 2.8.5.201 -Force to install the provider from a computer with an internet connection.

  2. After the install, you can find the provider installed in $env:ProgramFiles\PackageManagement\ReferenceAssemblies\\\<ProviderName\>\\\<ProviderVersion\> or $env:LOCALAPPDATA\PackageManagement\ProviderAssemblies\\\<ProviderName\>\\\<ProviderVersion\>.

  3. Place the folder, which in this case is the Nuget folder, in the corresponding location on your target computer. If your target computer is a Nano server, you need to run Install-PackageProvider from Nano Server to download the correct Nuget binaries.

  4. Restart PowerShell to auto-load the package provider. Alternatively, run Get-PackageProvider -ListAvailable to list all the package providers available on the computer. Then use Import-PackageProvider -Name NuGet -RequiredVersion 2.8.5.201 to import the provider to the current Windows PowerShell session.

Self Join to get employee manager name

create view as 
(select 
e1.empno as PersonID,
e1.ename as PersonName,
e2.empno MANAGER_ID,
e2.ename MANAGER_NAME 
from 
employees e1 , employees e2 
where 
e2.empno=e1.mgr)

Why do you use typedef when declaring an enum in C++?

You do not need to do it. In C (not C++) you were required to use enum Enumname to refer to a data element of the enumerated type. To simplify it you were allowed to typedef it to a single name data type.

typedef enum MyEnum { 
  //...
} MyEnum;

allowed functions taking a parameter of the enum to be defined as

void f( MyEnum x )

instead of the longer

void f( enum MyEnum x )

Note that the name of the typename does not need to be equal to the name of the enum. The same happens with structs.

In C++, on the other hand, it is not required, as enums, classes and structs can be accessed directly as types by their names.

// C++
enum MyEnum {
   // ...
};
void f( MyEnum x ); // Correct C++, Error in C

HTTP GET Request in Node.js Express

If you just need to make simple get requests and don't need support for any other HTTP methods take a look at: simple-get:

var get = require('simple-get');

get('http://example.com', function (err, res) {
  if (err) throw err;
  console.log(res.statusCode); // 200
  res.pipe(process.stdout); // `res` is a stream
});

Excel VBA: function to turn activecell to bold

I use

            chartRange = xlWorkSheet.Rows[1];
            chartRange.Font.Bold = true;

to turn the first-row-cells-font into bold. And it works, and I am using also Excel 2007.

You can call in VBA directly

            ActiveCell.Font.Bold = True

With this code I create a timestamp in the active cell, with bold font and yellow background

           Private Sub Worksheet_SelectionChange(ByVal Target As Range)
               ActiveCell.Value = Now()
               ActiveCell.Font.Bold = True
               ActiveCell.Interior.ColorIndex = 6
           End Sub

sendUserActionEvent() is null

Same issue on a Galaxy Tab and on a Xperia S, after uninstall and install again it seems that disappear.

The code that suddenly appear to raise this problem is this:

public void unlockMainActivity() {
    SharedPreferences prefs = getSharedPreferences("CALCULATOR_PREFS", 0);
    boolean hasCode = prefs.getBoolean("HAS_CODE", false);
    Context context = this.getApplicationContext();
    Intent intent = null;

    if (!hasCode) {
        intent = new Intent(context, WellcomeActivity.class);
    } else {
        intent = new Intent(context, CalculatingActivity.class);
    }
    intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    (context).startActivity(intent);
}

Should __init__() call the parent class's __init__()?

In Anon's answer:
"If you need something from super's __init__ to be done in addition to what is being done in the current class's __init__ , you must call it yourself, since that will not happen automatically"

It's incredible: he is wording exactly the contrary of the principle of inheritance.


It is not that "something from super's __init__ (...) will not happen automatically" , it is that it WOULD happen automatically, but it doesn't happen because the base-class' __init__ is overriden by the definition of the derived-clas __init__

So then, WHY defining a derived_class' __init__ , since it overrides what is aimed at when someone resorts to inheritance ??

It's because one needs to define something that is NOT done in the base-class' __init__ , and the only possibility to obtain that is to put its execution in a derived-class' __init__ function.
In other words, one needs something in base-class' __init__ in addition to what would be automatically done in the base-classe' __init__ if this latter wasn't overriden.
NOT the contrary.


Then, the problem is that the desired instructions present in the base-class' __init__ are no more activated at the moment of instantiation. In order to offset this inactivation, something special is required: calling explicitly the base-class' __init__ , in order to KEEP , NOT TO ADD, the initialization performed by the base-class' __init__ . That's exactly what is said in the official doc:

An overriding method in a derived class may in fact want to extend rather than simply replace the base class method of the same name. There is a simple way to call the base class method directly: just call BaseClassName.methodname(self, arguments).
http://docs.python.org/tutorial/classes.html#inheritance

That's all the story:

  • when the aim is to KEEP the initialization performed by the base-class, that is pure inheritance, nothing special is needed, one must just avoid to define an __init__ function in the derived class

  • when the aim is to REPLACE the initialization performed by the base-class, __init__ must be defined in the derived-class

  • when the aim is to ADD processes to the initialization performed by the base-class, a derived-class' __init__ must be defined , comprising an explicit call to the base-class __init__


What I feel astonishing in the post of Anon is not only that he expresses the contrary of the inheritance theory, but that there have been 5 guys passing by that upvoted without turning a hair, and moreover there have been nobody to react in 2 years in a thread whose interesting subject must be read relatively often.

How do I copy a string to the clipboard?

you can try this:

command = 'echo content |clip'
subprocess.check_call(command, shell=True)

How do you round a floating point number in Perl?

Output of perldoc -q round

Does Perl have a round() function? What about ceil() and floor()? Trig functions?

Remember that int() merely truncates toward 0. For rounding to a certain number of digits, sprintf() or printf() is usually the easiest route.

    printf("%.3f", 3.1415926535);       # prints 3.142

The POSIX module (part of the standard Perl distribution) implements ceil(), floor(), and a number of other mathematical and trigonometric functions.

    use POSIX;
    $ceil   = ceil(3.5);                        # 4
    $floor  = floor(3.5);                       # 3

In 5.000 to 5.003 perls, trigonometry was done in the Math::Complex module. With 5.004, the Math::Trig module (part of the standard Perl distribution) implements the trigonometric functions. Internally it uses the Math::Complex module and some functions can break out from the real axis into the complex plane, for example the inverse sine of 2.

Rounding in financial applications can have serious implications, and the rounding method used should be specified precisely. In these cases, it probably pays not to trust whichever system rounding is being used by Perl, but to instead implement the rounding function you need yourself.

To see why, notice how you'll still have an issue on half-way-point alternation:

    for ($i = 0; $i < 1.01; $i += 0.05) { printf "%.1f ",$i}

    0.0 0.1 0.1 0.2 0.2 0.2 0.3 0.3 0.4 0.4 0.5 0.5 0.6 0.7 0.7
    0.8 0.8 0.9 0.9 1.0 1.0

Don't blame Perl. It's the same as in C. IEEE says we have to do this. Perl numbers whose absolute values are integers under 2**31 (on 32 bit machines) will work pretty much like mathematical integers. Other numbers are not guaranteed.

moment.js get current time in milliseconds?

To get the current time's milliseconds, use http://momentjs.com/docs/#/get-set/millisecond/

var timeInMilliseconds = moment().milliseconds();

PHP Check for NULL

Use is_null or === operator.

is_null($result['column'])

$result['column'] === NULL

Why is SQL Server 2008 Management Studio Intellisense not working?

Here is the official word on this from MS.

http://support.microsoft.com/kb/2531482

Their solution is the same as above, install the SQL Server 2008 R2 updates with the version 10.50.1777.0.

http://support.microsoft.com/kb/2507770

PHPMailer character encoding issues

To avoid problems of character encoding in sending emails using the class PHPMailer we can configure it to send it with UTF-8 character encoding using the "CharSet" parameter, as we can see in the following Php code:

$mail = new PHPMailer();
$mail->From = '[email protected]';
$mail->FromName = 'Mi nombre';
$mail->AddAddress('[email protected]');
$mail->Subject = 'Prueba';
$mail->Body = '';
$mail->IsHTML(true);


// Active condition utf-8
$mail->CharSet = 'UTF-8';


// Send mail
$mail->Send();

Convert Dictionary to JSON in Swift

Swift 3:

let jsonData = try? JSONSerialization.data(withJSONObject: dict, options: [])
let jsonString = String(data: jsonData!, encoding: .utf8)!
print(jsonString)

Setting width to wrap_content for TextView through code

TextView pf = new TextView(context);
pf.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

For different layouts like ConstraintLayout and others, they have their own LayoutParams, like so:

pf.setLayoutParams(new ConstraintLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)); 

or

parentView.addView(pf, new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));

libclntsh.so.11.1: cannot open shared object file.

I have copied all library files from installer media databases/stage/ext/lib to $ORACLE_HOME/lib and it resolved the issue.

Get each line from textarea

Old tread...? Well, someone may bump into this...

Please check out http://telamenta.com/techarticle/php-explode-newlines-and-you

Rather than using:

$values = explode("\n", $value_string);

Use a safer method like:

$values = preg_split('/[\n\r]+/', $value_string);

Dynamic function name in javascript?

Dynamic methods of an object may be created using Object Literal Extensions provided by ECMAScript 2015 (ES6):

const postfixes = ['foo', 'bar'];

const mainObj = {};

const makeDynamic = (postfix) => {
  const newMethodName = 'instance: ' + postfix;
  const tempObj = {
    [newMethodName]() {
      console.log(`called method ${newMethodName}`);
    }
  }
  Object.assign(mainObj, tempObj);
  return mainObj[newMethodName]();
}

const processPostfixes = (postfixes) => { 
  for (const postfix of postfixes) {
    makeDynamic(postfix); 
  }
};

processPostfixes(postfixes);

console.log(mainObj);

The output of running the code above is:

"called method instance: foo"
"called method instance: bar"
Object {
  "instance: bar": [Function anonymous],
  "instance: foo": [Function anonymous]
}

Autoresize View When SubViews are Added

Yes, it is because you are using auto layout. Setting the view frame and resizing mask will not work.

You should read Working with Auto Layout Programmatically and Visual Format Language.

You will need to get the current constraints, add the text field, adjust the contraints for the text field, then add the correct constraints on the text field.

How do I read CSV data into a record array in NumPy?

I would suggest using tables (pip3 install tables). You can save your .csv file to .h5 using pandas (pip3 install pandas),

import pandas as pd
data = pd.read_csv("dataset.csv")
store = pd.HDFStore('dataset.h5')
store['mydata'] = data
store.close()

You can then easily, and with less time even for huge amount of data, load your data in a NumPy array.

import pandas as pd
store = pd.HDFStore('dataset.h5')
data = store['mydata']
store.close()

# Data in NumPy format
data = data.values

Detach (move) subdirectory into separate Git repository

Update: This process is so common, that the git team made it much simpler with a new tool, git subtree. See here: Detach (move) subdirectory into separate Git repository


You want to clone your repository and then use git filter-branch to mark everything but the subdirectory you want in your new repo to be garbage-collected.

  1. To clone your local repository:

    git clone /XYZ /ABC
    

    (Note: the repository will be cloned using hard-links, but that is not a problem since the hard-linked files will not be modified in themselves - new ones will be created.)

  2. Now, let us preserve the interesting branches which we want to rewrite as well, and then remove the origin to avoid pushing there and to make sure that old commits will not be referenced by the origin:

    cd /ABC
    for i in branch1 br2 br3; do git branch -t $i origin/$i; done
    git remote rm origin
    

    or for all remote branches:

    cd /ABC
    for i in $(git branch -r | sed "s/.*origin\///"); do git branch -t $i origin/$i; done
    git remote rm origin
    
  3. Now you might want to also remove tags which have no relation with the subproject; you can also do that later, but you might need to prune your repo again. I did not do so and got a WARNING: Ref 'refs/tags/v0.1' is unchanged for all tags (since they were all unrelated to the subproject); additionally, after removing such tags more space will be reclaimed. Apparently git filter-branch should be able to rewrite other tags, but I could not verify this. If you want to remove all tags, use git tag -l | xargs git tag -d.

  4. Then use filter-branch and reset to exclude the other files, so they can be pruned. Let's also add --tag-name-filter cat --prune-empty to remove empty commits and to rewrite tags (note that this will have to strip their signature):

    git filter-branch --tag-name-filter cat --prune-empty --subdirectory-filter ABC -- --all
    

    or alternatively, to only rewrite the HEAD branch and ignore tags and other branches:

    git filter-branch --tag-name-filter cat --prune-empty --subdirectory-filter ABC HEAD
    
  5. Then delete the backup reflogs so the space can be truly reclaimed (although now the operation is destructive)

    git reset --hard
    git for-each-ref --format="%(refname)" refs/original/ | xargs -n 1 git update-ref -d
    git reflog expire --expire=now --all
    git gc --aggressive --prune=now
    

    and now you have a local git repository of the ABC sub-directory with all its history preserved.

Note: For most uses, git filter-branch should indeed have the added parameter -- --all. Yes that's really --space-- all. This needs to be the last parameters for the command. As Matli discovered, this keeps the project branches and tags included in the new repo.

Edit: various suggestions from comments below were incorporated to make sure, for instance, that the repository is actually shrunk (which was not always the case before).

How do I select a random value from an enumeration?

Here is a generic function for it. Keep the RNG creation outside the high frequency code.

public static Random RNG = new Random();

public static T RandomEnum<T>()
{  
    Type type = typeof(T);
    Array values = Enum.GetValues(type);
    lock(RNG)
    {
        object value= values.GetValue(RNG.Next(values.Length));
        return (T)Convert.ChangeType(value, type);
    }
}

Usage example:

System.Windows.Forms.Keys randomKey = RandomEnum<System.Windows.Forms.Keys>();

Setting a windows batch file variable to the day of the week

This works for me

FOR /F "tokens=3" %%a in ('robocopy ^|find "Started"') DO SET TODAY=%%a

Compare a string using sh shell

Of the 4 shells that I've tested, ABC -eq XYZ evaluates to true in the test builtin for zsh and ksh. The expression evaluates to false under /usr/bin/test and the builtins for dash and bash. In ksh and zsh, the strings are converted to numerical values and are equal since they are both 0. IMO, the behavior of the builtins for ksh and zsh is incorrect, but the spec for test is ambiguous on this.

heroku - how to see all the logs

You need to have some logs draining implemented and should be draining your logs there, to see all of the logs (manage historical logs as well):

  1. First option - Splunk can be used: you can drain all your logs like:
heroku drains:add syslog+tls://splunk-server.com:514 -a app_name

And then login into your splunk server and search for any number of logs. I am using Splunk and this is working perfectly fine for me.

  1. Second option - You can purchase add on to your App, like given below: (I haven't used these options, however these are the available ones).

    • Timber.io
    • Sumo Logic
    • LogEnteries
    • Log DNA
    • Papertrail

You can also have a look at below options: If you want to have your logs in JSON format, as it will help if your are pushing your logs to external system like Splunk/ELK, it would become easy (performance wise also) to search in JSON.

https://github.com/goodeggs/heroku-log-normalizer

It is not having Readme.md, but some explanation is given at https://github.com/goodeggs/bites/issues/20

Lastly

And you can always use below command as mentioned by other users already:

The following command will tail the generating logs on heroku

heroku logs -t -a <app_name>

The following comand will show the 1000 number of lines of logs from heroku

heroku logs -n 1000 -a <app_name>

Note only 1500 latest lines of logs are available and rest of them gets deleted from heroku dyno.

python ignore certificate validation urllib2

In the meantime urllib2 seems to verify server certificates by default. The warning, that was shown in the past disappeared for 2.7.9 and I currently ran into this problem in a test environment with a self signed certificate (and Python 2.7.9).

My evil workaround (don't do this in production!):

import urllib2
import ssl

ctx = ssl.create_default_context()
ctx.check_hostname = False
ctx.verify_mode = ssl.CERT_NONE

urllib2.urlopen("https://your-test-server.local", context=ctx)

According to docs calling SSLContext constructor directly should work, too. I haven't tried that.

ionic build Android | error: No installed build tools found. Please install the Android build tools

I have tried all the above solution. None works. Until I was linked to https://forum.ionicframework.com/t/ionic-v4-no-installed-build-tools-found/152150.

Apparently, you must run the command as root. Sudo is not enough. You need to change to root user before you can run all the commands.

Access Google's Traffic Data through a Web Service

Rather than trying to pull the raw traffic data, you can try a different approach. The Google Directions API allows you to query the api with a particular route and returns a JSON string or XML element as a result. This result includes the element - ' duration_in_traffic ' This indicates the total duration of the particular leg of the journey, taking into account current traffic conditions. (for information on 'leg' and other elements of the JSON string returned by the Directions API refer link below)

https://developers.google.com/maps/documentation/directions/#JSON I haven't tried this myself but just something I came across in the documentation.

python location on mac osx

installed with 'brew install python3', found it here enter image description here

How to force IE to reload javascript?

Paolo's general idea (i.e. effectively changing some part of the request uri) is your best bet. However, I'd suggest using a more static value such as a version number that you update when you have changed your script file so that you can still get the performance gains of caching.

So either something like this:

<script src="/my/js/file.js?version=2.1.3" ></script>

or maybe

<script src="/my/js/file.2.1.3.js" ></script>

I prefer the first option because it means you can maintain the one file instead of having to constantly rename it (which for example maintains consistent version history in your source control). Of course either one (as I've described them) would involve updating your include statements each time, so you may want to come up with a dynamic way of doing it, such as replacing a fixed value with a dynamic one every time you deploy (using Ant or whatever).

Formatting MM/DD/YYYY dates in textbox in VBA

This is the same concept as Siddharth Rout's answer. But I wanted a date picker which could be fully customized so that the look and feel could be tailored to whatever project it's being used in.

You can click this link to download the custom date picker I came up with. Below are some screenshots of the form in action.

Three example calendars

To use the date picker, simply import the CalendarForm.frm file into your VBA project. Each of the calendars above can be obtained with one single function call. The result just depends on the arguments you use (all of which are optional), so you can customize it as much or as little as you want.

For example, the most basic calendar on the left can be obtained by the following line of code:

MyDateVariable = CalendarForm.GetDate

That's all there is to it. From there, you just include whichever arguments you want to get the calendar you want. The function call below will generate the green calendar on the right:

MyDateVariable = CalendarForm.GetDate( _
    SelectedDate:=Date, _
    DateFontSize:=11, _
    TodayButton:=True, _
    BackgroundColor:=RGB(242, 248, 238), _
    HeaderColor:=RGB(84, 130, 53), _
    HeaderFontColor:=RGB(255, 255, 255), _
    SubHeaderColor:=RGB(226, 239, 218), _
    SubHeaderFontColor:=RGB(55, 86, 35), _
    DateColor:=RGB(242, 248, 238), _
    DateFontColor:=RGB(55, 86, 35), _
    SaturdayFontColor:=RGB(55, 86, 35), _
    SundayFontColor:=RGB(55, 86, 35), _
    TrailingMonthFontColor:=RGB(106, 163, 67), _
    DateHoverColor:=RGB(198, 224, 180), _
    DateSelectedColor:=RGB(169, 208, 142), _
    TodayFontColor:=RGB(255, 0, 0), _
    DateSpecialEffect:=fmSpecialEffectRaised)

Here is a small taste of some of the features it includes. All options are fully documented in the userform module itself:

  • Ease of use. The userform is completely self-contained, and can be imported into any VBA project and used without much, if any additional coding.
  • Simple, attractive design.
  • Fully customizable functionality, size, and color scheme
  • Limit user selection to a specific date range
  • Choose any day for the first day of the week
  • Include week numbers, and support for ISO standard
  • Clicking the month or year label in the header reveals selectable comboboxes
  • Dates change color when you mouse over them

php exec() is not executing the command

I already said that I was new to exec() function. After doing some more digging, I came upon 2>&1 which needs to be added at the end of command in exec().

Thanks @mattosmat for pointing it out in the comments too. I did not try this at once because you said it is a Linux command, I am on Windows.

So, what I have discovered, the command is actually executing in the back-end. That is why I could not see it actually running, which I was expecting to happen.

For all of you, who had similar problem, my advise is to use that command. It will point out all the errors and also tell you info/details about execution.

exec('some_command 2>&1', $output);
print_r($output);  // to see the response to your command

Thanks for all the help guys, I appreciate it ;)

Is it possible to use jQuery to read meta tags

Just use something like:

var author = $('meta[name=author]').attr('content');

Remove Top Line of Text File with PowerShell

I just learned from a website:

Get-ChildItem *.txt | ForEach-Object { (get-Content $_) | Where-Object {(1) -notcontains $_.ReadCount } | Set-Content -path $_ }

Or you can use the aliases to make it short, like:

gci *.txt | % { (gc $_) | ? { (1) -notcontains $_.ReadCount } | sc -path $_ }

How to delete rows in tables that contain foreign keys to other tables

If you have multiply rows to delete and you don't want to alter the structure of your tables you can use cursor. 1-You first need to select rows to delete(in a cursor) 2-Then for each row in the cursor you delete the referencing rows and after that delete the row him self.

Ex:

--id is primary key of MainTable
    declare @id int
    set @id = 1
    declare theMain cursor for select FK from MainTable where MainID = @id
    declare @fk_Id int
    open theMain
    fetch next from theMain into @fk_Id
    while @@fetch_status=0
    begin
        --fkid is the foreign key 
        --Must delete from Main Table first then child.
        delete from MainTable where fkid = @fk_Id
        delete from ReferencingTable where fkid = @fk_Id
        fetch next from theMain into @fk_Id
    end
    close theMain
    deallocate theMain

hope is useful

Get all LI elements in array

You can get a NodeList to iterate through by using getElementsByTagName(), like this:

var lis = document.getElementById("navbar").getElementsByTagName("li");

You can test it out here. This is a NodeList not an array, but it does have a .length and you can iterate over it like an array.

Label python data points on plot

I had a similar issue and ended up with this:

enter image description here

For me this has the advantage that data and annotation are not overlapping.

from matplotlib import pyplot as plt
import numpy as np

fig = plt.figure()
ax = fig.add_subplot(111)

A = -0.75, -0.25, 0, 0.25, 0.5, 0.75, 1.0
B = 0.73, 0.97, 1.0, 0.97, 0.88, 0.73, 0.54

plt.plot(A,B)

# annotations at the side (ordered by B values)
x0,x1=ax.get_xlim()
y0,y1=ax.get_ylim()
for ii, ind in enumerate(np.argsort(B)):
    x = A[ind]
    y = B[ind]
    xPos = x1 + .02 * (x1 - x0)
    yPos = y0 + ii * (y1 - y0)/(len(B) - 1)
    ax.annotate('',#label,
          xy=(x, y), xycoords='data',
          xytext=(xPos, yPos), textcoords='data',
          arrowprops=dict(
                          connectionstyle="arc3,rad=0.",
                          shrinkA=0, shrinkB=10,
                          arrowstyle= '-|>', ls= '-', linewidth=2
                          ),
          va='bottom', ha='left', zorder=19
          )
    ax.text(xPos + .01 * (x1 - x0), yPos,
            '({:.2f}, {:.2f})'.format(x,y),
            transform=ax.transData, va='center')

plt.grid()
plt.show()

Using the text argument in .annotate ended up with unfavorable text positions. Drawing lines between a legend and the data points is a mess, as the location of the legend is hard to address.

How to grey out a button?

I tried the above solutions but none of them seemed to work for me. I went with the following option:

<!-- button_color_selector.xml -->
<selector xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:color="@color/colorAccent" android:state_enabled="true"/>
    <item android:color="@color/colorAccentLight" android:state_enabled="false"/>
</selector>
<com.google.android.material.button.MaterialButton
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:backgroundTint="@color/button_color_selector"
                .../>

What is the best way to create a string array in python?

Sometimes I need a empty char array. You cannot do "np.empty(size)" because error will be reported if you fill in char later. Then I usually do something quite clumsy but it is still one way to do it:

# Suppose you want a size N char array
charlist = [' ']*N # other preset character is fine as well, like 'x'
chararray = np.array(charlist)
# Then you change the content of the array
chararray[somecondition1] = 'a'
chararray[somecondition2] = 'b'

The bad part of this is that your array has default values (if you forget to change them).

WCF Service , how to increase the timeout?

In your binding configuration, there are four timeout values you can tweak:

<bindings>
  <basicHttpBinding>
    <binding name="IncreasedTimeout"
             sendTimeout="00:25:00">
    </binding>
  </basicHttpBinding>

The most important is the sendTimeout, which says how long the client will wait for a response from your WCF service. You can specify hours:minutes:seconds in your settings - in my sample, I set the timeout to 25 minutes.

The openTimeout as the name implies is the amount of time you're willing to wait when you open the connection to your WCF service. Similarly, the closeTimeout is the amount of time when you close the connection (dispose the client proxy) that you'll wait before an exception is thrown.

The receiveTimeout is a bit like a mirror for the sendTimeout - while the send timeout is the amount of time you'll wait for a response from the server, the receiveTimeout is the amount of time you'll give you client to receive and process the response from the server.

In case you're send back and forth "normal" messages, both can be pretty short - especially the receiveTimeout, since receiving a SOAP message, decrypting, checking and deserializing it should take almost no time. The story is different with streaming - in that case, you might need more time on the client to actually complete the "download" of the stream you get back from the server.

There's also openTimeout, receiveTimeout, and closeTimeout. The MSDN docs on binding gives you more information on what these are for.

To get a serious grip on all the intricasies of WCF, I would strongly recommend you purchase the "Learning WCF" book by Michele Leroux Bustamante:

Learning WCF http://ecx.images-amazon.com/images/I/51GNuqUJq%2BL._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA240_SH20_OU01_.jpg

and you also spend some time watching her 15-part "WCF Top to Bottom" screencast series - highly recommended!

For more advanced topics I recommend that you check out Juwal Lowy's Programming WCF Services book.

Programming WCF http://ecx.images-amazon.com/images/I/41odWcLoGAL._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA240_SH20_OU01_.jpg

Moment js get first and last day of current month

There would be another way to do this:

var begin = moment().format("YYYY-MM-01");
var end = moment().format("YYYY-MM-") + moment().daysInMonth();

What is an application binary interface (ABI)?

In short and in philosophy, only things of a kind can get along well, and the ABI could be seen as the kind of which software stuff work together.

Reading JSON POST using PHP

You have empty $_POST. If your web-server wants see data in json-format you need to read the raw input and then parse it with JSON decode.

You need something like that:

$json = file_get_contents('php://input');
$obj = json_decode($json);

Also you have wrong code for testing JSON-communication...

CURLOPT_POSTFIELDS tells curl to encode your parameters as application/x-www-form-urlencoded. You need JSON-string here.

UPDATE

Your php code for test page should be like that:

$data_string = json_encode($data);

$ch = curl_init('http://webservice.local/');
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
        'Content-Type: application/json',
        'Content-Length: ' . strlen($data_string))
);

$result = curl_exec($ch);
$result = json_decode($result);
var_dump($result);

Also on your web-service page you should remove one of the lines header('Content-type: application/json');. It must be called only once.

Breaking to a new line with inline-block?

You can try with:

    display: inline-table;

For me it works fine.

Convert InputStream to BufferedReader

A BufferedReader constructor takes a reader as argument, not an InputStream. You should first create a Reader from your stream, like so:

Reader reader = new InputStreamReader(is);
BufferedReader br = new BufferedReader(reader);

Preferrably, you also provide a Charset or character encoding name to the StreamReader constructor. Since a stream just provides bytes, converting these to text means the encoding must be known. If you don't specify it, the system default is assumed.

Error: "Input is not proper UTF-8, indicate encoding !" using PHP's simplexml_load_string

We recently ran into a similar issue and was unable to find anything obvious as the cause. There turned out to be a control character in our string but when we outputted that string to the browser that character was not visible unless we copied the text into an IDE.

We managed to solve our problem thanks to this post and this:

preg_replace('/[\x00-\x1F\x7F]/', '', $input);

SQL Server after update trigger

First off, your trigger as you already see is going to update every record in the table. There is no filtering done to accomplish jus the rows changed.

Secondly, you're assuming that only one row changes in the batch which is incorrect as multiple rows could change.

The way to do this properly is to use the virtual inserted and deleted tables: http://msdn.microsoft.com/en-us/library/ms191300.aspx