Programs & Examples On #Game ai

Artificial intelligence techniques applied to video games.

Adjust icon size of Floating action button (fab)

Make this entry in dimens

<!--Floating action button-->
<dimen name="design_fab_image_size" tools:override="true">36dp</dimen>

Here 36dp is icon size on floating point button. This will set 36dp size for all icons for floating action button.

Updates As Per Comments

If you want to set icon size to particular Floating Action Button just go with Floating action button attributes like app:fabSize="normal" and android:scaleType="center".

  <!--app:fabSize decides size of floating action button You can use normal, auto or mini as per need-->
  app:fabSize="normal" 

  <!--android:scaleType decides how the icon drawable will be scaled on Floating action button. You can use center(to show scr image as original), fitXY, centerCrop, fitCenter, fitEnd, fitStart, centerInside.-->
  android:scaleType="center"

How do I get Fiddler to stop ignoring traffic to localhost?

For Fiddler to capture traffic from localhost on local IIS, there are 3 steps (It worked on my computer):

  1. Click Tools > Fiddler Options. Ensure Allow remote clients to connect is checked. Close Fiddler.

enter image description here

  1. Create a new DWORD named ReverseProxyForPort inside KEY_CURRENT_USER\SOFTWARE\Microsoft\Fiddler2. Set the DWORD to port 80 (choose decimal here). Restart Fiddler.

enter image description here

  1. Add port 8888 to the addresses defined in your client. For example localhost:8888/MyService/WebAPI/v1/

Get class name of object as string in Swift

To get class name as String declare your class as following

@objc(YourClassName) class YourClassName{}

And get class name using following syntax

NSStringFromClass(YourClassName)

Merge Cell values with PHPExcel - PHP

Try this

$objPHPExcel->getActiveSheet()->mergeCells('A1:C1');

Why am I getting the message, "fatal: This operation must be run in a work tree?"

Edited the config file and changed bare = true to bare = false

Center text output from Graphics.DrawString()

I'd like to add another vote for the StringFormat object. You can use this simply to specify "center, center" and the text will be drawn centrally in the rectangle or points provided:

StringFormat format = new StringFormat();
format.LineAlignment = StringAlignment.Center;
format.Alignment = StringAlignment.Center;

However there is one issue with this in CF. If you use Center for both values then it turns TextWrapping off. No idea why this happens, it appears to be a bug with the CF.

Relative div height

Basically, the problem lies in block12. for the block1/2 to take up the total height of the block12, it must have a defined height. This stack overflow post explains that in really good detail.

So setting a defined height for block12 will allow you to set a proper height. I have created an example on JSfiddle that will show you the the blocks can be floated next to one another if the block12 div is set to a standard height through out the page.

Here is an example including a header and block3 div with some content in for examples.

#header{
   position:absolute;
   top:0;
   left:0;
   width:100%;
   height:20%;
    }

    #block12{
    position:absolute;
    top:20%;
    width:100%;
    left:0;
    height:40%;
    }
    #block1,#block2{
    float:left;
    overflow-y: scroll;
    text-align:center;
    color:red;
    width:50%;
    height:100%;

    }
 #clear{clear:both;}
 #block3{
    position:absolute;
    bottom:0;
    color:blue;
    height:40%;

    }

How to format numbers by prepending 0 to single-digit numbers?

Use the toLocaleString() method in any number. So for the number 6, as seen below, you can get the desired results.

(6).toLocaleString('en-US', {minimumIntegerDigits: 2, useGrouping:false})

Will generate the string '06'.

uppercase first character in a variable with bash

just for fun here you are :

foo="bar";    

echo $foo | awk '{$1=toupper(substr($1,0,1))substr($1,2)}1'
# or
echo ${foo^}
# or
echo $foo | head -c 1 | tr [a-z] [A-Z]; echo $foo | tail -c +2
# or
echo ${foo:1} | sed -e 's/^./\B&/'

SQL Server: Multiple table joins with a WHERE clause

You need to do a LEFT JOIN.

SELECT Computer.ComputerName, Application.Name, Software.Version
FROM Computer
JOIN dbo.Software_Computer
    ON Computer.ID = Software_Computer.ComputerID
LEFT JOIN dbo.Software
    ON Software_Computer.SoftwareID = Software.ID
RIGHT JOIN dbo.Application
    ON Application.ID = Software.ApplicationID
WHERE Computer.ID = 1 

Here is the explanation:

The result of a left outer join (or simply left join) for table A and B always contains all records of the "left" table (A), even if the join-condition does not find any matching record in the "right" table (B). This means that if the ON clause matches 0 (zero) records in B, the join will still return a row in the result—but with NULL in each column from B. This means that a left outer join returns all the values from the left table, plus matched values from the right table (or NULL in case of no matching join predicate). If the right table returns one row and the left table returns more than one matching row for it, the values in the right table will be repeated for each distinct row on the left table. From Oracle 9i onwards the LEFT OUTER JOIN statement can be used as well as (+).

How To limit the number of characters in JTextField?

I have solved this problem by using the following code segment:

private void jTextField1KeyTyped(java.awt.event.KeyEvent evt) {
    boolean max = jTextField1.getText().length() > 4;
    if ( max ){
        evt.consume();
    }        
}

jQuery val is undefined?

You should call the events after the document is ready, like this:

$(document).ready(function () {
  // Your code
});

This is because you are trying to manipulate elements before they are rendered by the browser.

So, in the case you posted it should look something like this

$(document).ready(function () {
  var editorTitle = $('#editorTitle').val();
  var editorText = $('#editorText').html();
});

Hope it helps.

Tips: always save your jQuery object in a variable for later use and only code that really need to run after the document have loaded should go inside the ready() function.

Rename file with Git

You've got "Bad Status" its because the target file cannot find or not present, like for example you call README file which is not in the current directory.

How do you remove columns from a data.frame?

For clarity purposes, I often use the select argument in subset. With newer folks, I've learned that keeping the # of commands they need to pick up to a minimum helps adoption. As their skills increase, so too will their coding ability. And subset is one of the first commands I show people when needing to select data within a given criteria.

Something like:

> subset(mtcars, select = c("mpg", "cyl", "vs", "am"))
                     mpg cyl vs am
Mazda RX4           21.0   6  0  1
Mazda RX4 Wag       21.0   6  0  1
Datsun 710          22.8   4  1  1
....

I'm sure this will test slower than most other solutions, but I'm rarely at the point where microseconds make a difference.

Oracle 12c Installation failed to access the temporary location

This problem arises due to the administrative share.

Here is the solution :

  1. Set HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System DWORD value: LocalAccountTokenFilterPolicy to 1

  2. Go to this link: http://www.snehashish.com/install-oracle-database-12c-software/ Follow 8th point.
    It helped me a lot.
    After creating the hidden share (c$) it should look like this (you can ignore the description tab)

And for remaining you can follow the above link.

And let me know if it worked or not.

Java string replace and the NUL (NULL, ASCII 0) character?

Should be probably changed to

firstName = firstName.trim().replaceAll("\\.", "");

How do I use Access-Control-Allow-Origin? Does it just go in between the html head tags?

If you use Java and spring MVC you just need to add the following annotation to your method returning your page :

@CrossOrigin(origins = "*")

"*" is to allow your page to be accessible from anywhere. See https://developer.mozilla.org/fr/docs/Web/HTTP/Headers/Access-Control-Allow-Origin for more details about that.

Fixing Sublime Text 2 line endings?

The comment states

// Determines what character(s) are used to terminate each line in new files.
// Valid values are 'system' (whatever the OS uses), 'windows' (CRLF) and
// 'unix' (LF only).

You are setting

"default_line_ending": "LF",

You should set

"default_line_ending": "unix",

In Python, how to display current time in readable format

import time
time.strftime('%H:%M%p %Z on %b %d, %Y')

This may come in handy

react-native - Fit Image in containing View, not the whole screen size

Simply You need to pass resizeMode like this to fit in your image in containing view

<Image style={styles.imageStyle} resizeMode={'cover'} source={item.image}/>

const style = StyleSheet.create({
  imageStyle: {
      alignSelf: 'center',
      height:'100%', 
      width:'100%'
    },]
})

Renaming part of a filename

There are a couple of variants of a rename command, in your case, it may be as simple as

rename ABC XYZ *.dat

You may have a version which takes a Perl regex;

rename 's/ABC/XYZ/' *.dat

Launch an event when checking a checkbox in Angular2

If you add double paranthesis to the ngModel reference you get a two-way binding to your model property. That property can then be read and used in the event handler. In my view that is the most clean approach.

<input type="checkbox" [(ngModel)]="myModel.property" (ngModelChange)="processChange()" />

How to download file from database/folder using php

I have changed to your code with little modification will works well. Here is the code:

butangDonload.php

<?php
$file = "logo_ldg.png"; //Let say If I put the file name Bang.png
echo "<a href='download1.php?nama=".$file."'>download</a> ";
?>

download.php

<?php
$name= $_GET['nama'];

    header('Content-Description: File Transfer');
    header('Content-Type: application/force-download');
    header("Content-Disposition: attachment; filename=\"" . basename($name) . "\";");
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($name));
    ob_clean();
    flush();
    readfile("your_file_path/".$name); //showing the path to the server where the file is to be download
    exit;
?>

Here you need to show the path from where the file to be download. i.e. will just give the file name but need to give the file path for reading that file. So, it should be replaced by I have tested by using your code and modifying also will works.

How to clear jQuery validation error messages?

I tested with:

$("div.error").remove();
$(".error").removeClass("error");

It will be ok, when you need to validate it again.

Pass a password to ssh in pure bash

Since there were no exact answers to my question, I made some investigation why my code doesn't work when there are other solutions that works, and decided to post what I found to complete the subject.
As it turns out:

"ssh uses direct TTY access to make sure that the password is indeed issued by an interactive keyboard user." sshpass manpage

which answers the question, why the pipes don't work in this case. The obvious solution was to create conditions so that ssh "thought" that it is run in the regular terminal and since it may be accomplished by simple posix functions, it is beyond what simple bash offers.

How to insert an element after another element in JavaScript without using a library?

a robust implementation of insertAfter.

// source: https://github.com/jserz/domPlus/blob/master/src/insertAfter()/insertAfter.js
Node.prototype.insertAfter = Node.prototype.insertAfter || function (newNode, referenceNode) {
  function isNode(node) {
    return node instanceof Node;
  }

  if(arguments.length < 2){
    throw(new TypeError("Failed to execute 'insertAfter' on 'Node': 2 arguments required, but only "+ arguments.length +" present."));
  }

  if(isNode(newNode)){
    if(referenceNode === null || referenceNode === undefined){
      return this.insertBefore(newNode, referenceNode);
    }

    if(isNode(referenceNode)){
      return this.insertBefore(newNode, referenceNode.nextSibling);
    }

    throw(new TypeError("Failed to execute 'insertAfter' on 'Node': parameter 2 is not of type 'Node'."));
  }

  throw(new TypeError("Failed to execute 'insertAfter' on 'Node': parameter 1 is not of type 'Node'."));
};

How to read and write to a text file in C++?

To read you should create an instance of ifsteam and not ofstream.

ifstream iusrfile;

You should open the file in read mode.

iusrfile.open("usrfile.txt", ifstream::in);

Also this statement is not correct.

cout<<iusrfile;

If you are trying to print the data you read from the file you should do:

cout<<usr;

You can read more about ifstream and its API here

Colspan all columns

I have IE 7.0, Firefox 3.0 and Chrome 1.0

The colspan="0" attribute in a TD is NOT spanning across all TDs in any of the above browsers.

Maybe not recommended as proper markup practice, but if you give a higher colspan value than the total possible no. of columns in other rows, then the TD would span all the columns.

This does NOT work when the table-layout CSS property is set to fixed.

Once again, this is not the perfect solution but seems to work in the above mentioned 3 browser versions when the table-layout CSS property is automatic. Hope this helps.

FCM getting MismatchSenderId

Note: I had truncated the first part of the FCM token (before :) and the error was MismatchSenderId

Fixed my script and now everything works fine.

Run JavaScript when an element loses focus

You want to use the onblur event.

<input type="text" name="name" value="value" onblur="alert(1);"/>

Get local href value from anchor (a) tag

document.getElementById("aaa").href; //for example: http://example.com/sec/IF00.html

MYSQL into outfile "access denied" - but my user has "ALL" access.. and the folder is CHMOD 777

I tried all the solutions but it still wasn't sufficient. After some more digging I eventually found I had also to set the 'file_priv' flag, and restart mysql.

To resume :

Grant the privileges :

> GRANT ALL PRIVILEGES
  ON my_database.* 
  to 'my_user'@'localhost';

> GRANT FILE ON *.* TO my_user;

> FLUSH PRIVILEGES; 

Set the flag :

> UPDATE mysql.user SET File_priv = 'Y' WHERE user='my_user' AND host='localhost';

Finally restart the mysql server:

$ sudo service mysql restart

After that, I could write into the secure_file_priv directory. For me it was /var/lib/mysql-files/, but you can check it with the following command :

> SHOW VARIABLES LIKE "secure_file_priv";

Convert double to float in Java

This is a nice way to do it:

Double d = 0.5;
float f = d.floatValue();

if you have d as a primitive type just add one line:

double d = 0.5;
Double D = Double.valueOf(d);
float f = D.floatValue();

navbar color in Twitter Bootstrap

The best way currently to do the same would be to install LESS command line compiler using

$ npm install -g less jshint recess uglify-js

Once you have done this, then go to the less folder in the directory and then edit the file variables.less and you can change a lot of variables according to what you need including the color of the navigation bar

@navbarCollapseWidth:             979px;

@navbarHeight:                    40px;
@navbarBackgroundHighlight:       #ffffff;
@navbarBackground:                darken(@navbarBackgroundHighlight, 5%);
@navbarBorder:                    darken(@navbarBackground, 12%);

@navbarText:                      #777;
@navbarLinkColor:                 #777;
@navbarLinkColorHover:            @grayDark;
@navbarLinkColorActive:           @gray;
@navbarLinkBackgroundHover:       transparent;
@navbarLinkBackgroundActive:      darken(@navbarBackground, 5%);

Once you have done this, go to your bootstrap directory and run the command make.

ModuleNotFoundError: No module named 'sklearn'

I had the same issue as the author, and ran into the issue with and without Anaconda and regardless of Python version. Everyone's environment is different, but after resolving it for myself I think that in some cases it may be due to having multiple version of Python installed. Each installed Python version has its own \Lib\site-packages\ folder which can contain a unique set of modules for that Python version, and where the IDE looks into folder path that doesn't have scikit-learn in it.

One way to try solve the issue: you might clear your system of all other Python versions and their cached/temp files/system variables, and then only have one version of Python installed anywhere. Then install the dependencies Numpy and Scipy, and finally Scikit-learn.

More detailed steps:

  1. Uninstall all Python versions and their launchers (e.g. from Control Panel in Windows) except the one version you want to keep. Delete any old Python version folders in the Python directory --uninstalling doesn't remove all files.
  2. Remove other Python versions from your OS' Environment Variables (both under the system and user variables sections)
  3. Clear temporary files. For example, for Windows, delete all AppData Temp cache files (in C:\Users\YourUserName\AppData\Local\Temp). In addition, you could also do a Windows disk cleanup for other temporary files, and then reboot.
  4. If your IDE supports it, create a new virtual environment in Settings, then set your only installed Python version as the interpreter.
  5. In your IDE, install the dependencies Scipy and Numpy from the module list first, then install Scikit-Learn.

As some others have suggested, the key is making sure your environment is set up correctly where everything points to the correct library folder on your computer where the Sklearn package is located. There are a few ways this can be resolved. My approach was more drastic, but it turns out that I had a very messy Python setup on my system so I had to start fresh.

Will iOS launch my app into the background if it was force-quit by the user?

You can change your target's launch settings in "Manage Scheme" to Wait for <app>.app to be launched manually, which allows you debug by setting a breakpoint in application: didReceiveRemoteNotification: fetchCompletionHandler: and sending the push notification to trigger the background launch.

I'm not sure it'll solve the issue, but it may assist you with debugging for now.

screenshot

Count all values in a matrix greater than a value

This is very straightforward with boolean arrays:

p31 = numpy.asarray(o31)
za = (p31 < 200).sum() # p31<200 is a boolean array, so `sum` counts the number of True elements

Trying to create a file in Android: open failed: EROFS (Read-only file system)

To use internal storage for the application, you don't need permission, but you may need to use: File directory = getApplication().getCacheDir(); to get the allowed directory for the app.

Or:
getCashDir(); <-- should work
context.getCashDir(); (if in a broadcast receiver)
getDataDir(); <--Api 24

Center Triangle at Bottom of Div

Check this:

http://jsfiddle.net/SxKr5/3/

.hero1
{
    width: 90%;
    height: 200px;
    margin: auto;
    background-color: #e15915;
}

.hero2
{
    width: 0px;
    height: 0px;
    border-style: solid;
    margin: auto;
    border-width: 90px 58px 0 58px;
    border-color: #e15915 transparent transparent transparent;
    line-height: 0px;
    _border-color: #e15915 #000000 #000000 #000000;
    _filter: progid:DXImageTransform.Microsoft.Chroma(color='#000000')
}

Should I mix AngularJS with a PHP framework?

It seems you may be more comfortable with developing in PHP you let this hold you back from utilizing the full potential with web applications.

It is indeed possible to have PHP render partials and whole views, but I would not recommend it.

To fully utilize the possibilities of HTML and javascript to make a web application, that is, a web page that acts more like an application and relies heavily on client side rendering, you should consider letting the client maintain all responsibility of managing state and presentation. This will be easier to maintain, and will be more user friendly.

I would recommend you to get more comfortable thinking in a more API centric approach. Rather than having PHP output a pre-rendered view, and use angular for mere DOM manipulation, you should consider having the PHP backend output the data that should be acted upon RESTFully, and have Angular present it.

Using PHP to render the view:

/user/account

if($loggedIn)
{
    echo "<p>Logged in as ".$user."</p>";
}
else
{
    echo "Please log in.";
}

How the same problem can be solved with an API centric approach by outputting JSON like this:

api/auth/

{
  authorized:true,
  user: {
      username: 'Joe', 
      securityToken: 'secret'
  }
}

and in Angular you could do a get, and handle the response client side.

$http.post("http://example.com/api/auth", {})
.success(function(data) {
    $scope.isLoggedIn = data.authorized;
});

To blend both client side and server side the way you proposed may be fit for smaller projects where maintainance is not important and you are the single author, but I lean more towards the API centric way as this will be more correct separation of conserns and will be easier to maintain.

How to access the value of a promise?

When a promise is resolved/rejected, it will call its success/error handler:

var promiseB = promiseA.then(function(result) {
   // do something with result
});

The then method also returns a promise: promiseB, which will be resolved/rejected depending on the return value from the success/error handler from promiseA.

There are three possible values that promiseA's success/error handlers can return that will affect promiseB's outcome:

1. Return nothing --> PromiseB is resolved immediately, 
   and undefined is passed to the success handler of promiseB
2. Return a value --> PromiseB is resolved immediately,
   and the value is passed to the success handler of promiseB
3. Return a promise --> When resolved, promiseB will be resolved. 
   When rejected, promiseB will be rejected. The value passed to
   the promiseB's then handler will be the result of the promise

Armed with this understanding, you can make sense of the following:

promiseB = promiseA.then(function(result) {
  return result + 1;
});

The then call returns promiseB immediately. When promiseA is resolved, it will pass the result to promiseA's success handler. Since the return value is promiseA's result + 1, the success handler is returning a value (option 2 above), so promiseB will resolve immediately, and promiseB's success handler will be passed promiseA's result + 1.

How to set time to a date object in java

Calendar cal = Calendar.getInstance();
cal.set(Calendar.HOUR_OF_DAY,17);
cal.set(Calendar.MINUTE,30);
cal.set(Calendar.SECOND,0);
cal.set(Calendar.MILLISECOND,0);

Date d = cal.getTime();

Also See

Min / Max Validator in Angular 2 Final

To apply min/max validation on a number you will need to create a Custom Validator

Validators class currently only have a few validators, namely

  • required
  • requiredTrue
  • minlength
  • maxlength
  • pattern
  • nullValidator
  • compose
  • composeAsync

Validator: Here is toned down version of my number Validator, you can improve it as you like

static number(prms = {}): ValidatorFn {
    return (control: FormControl): {[key: string]: any} => {
      if(isPresent(Validators.required(control))) {
        return null;
      }
      
      let val: number = control.value;

      if(isNaN(val) || /\D/.test(val.toString())) {
        
        return {"number": true};
      } else if(!isNaN(prms.min) && !isNaN(prms.max)) {
        
        return val < prms.min || val > prms.max ? {"number": true} : null;
      } else if(!isNaN(prms.min)) {
        
        return val < prms.min ? {"number": true} : null;
      } else if(!isNaN(prms.max)) {
        
        return val > prms.max ? {"number": true} : null;
      } else {
        
        return null;
      }
    };
  }

Usage:

// check for valid number
var numberControl = new FormControl("", [Validators.required, CustomValidators.number()])

// check for valid number and min value  
var numberControl = new FormControl("", CustomValidators.number({min: 0}))

// check for valid number and max value
var numberControl = new FormControl("", CustomValidators.number({max: 20}))

// check for valid number and value range ie: [0-20]
var numberControl = new FormControl("", CustomValidators.number({min: 0, max: 20}))

Cannot resolve method 'getSupportFragmentManager ( )' inside Fragment

Also you can use AppCompatActivity instead of Activity.
Then getSupportFragmentManager() will work.
And also not forget to make your App theme extend AppCompat theme in this case

C/C++ include header file order

I follow two simple rules that avoid the vast majority of problems:

  1. All headers (and indeed any source files) should include what they need. They should not rely on their users including things.
  2. As an adjunct, all headers should have include guards so that they don't get included multiple times by over-ambitious application of rule 1 above.

I also follow the guidelines of:

  1. Include system headers first (stdio.h, etc) with a dividing line.
  2. Group them logically.

In other words:

#include <stdio.h>
#include <string.h>

#include "btree.h"
#include "collect_hash.h"
#include "collect_arraylist.h"
#include "globals.h"

Although, being guidelines, that's a subjective thing. The rules on the other hand, I enforce rigidly, even to the point of providing 'wrapper' header files with include guards and grouped includes if some obnoxious third-party developer doesn't subscribe to my vision :-)

How to detect if JavaScript is disabled?

Might sound a strange solution, but you can give it a try :

<?php $jsEnabledVar = 0; ?>    

<script type="text/javascript">
var jsenabled = 1;
if(jsenabled == 1)
{
   <?php $jsEnabledVar = 1; ?>
}
</script>

<noscript>
var jsenabled = 0;
if(jsenabled == 0)
{
   <?php $jsEnabledVar = 0; ?>
}
</noscript>

Now use the value of '$jsEnabledVar' throughout the page. You may also use it to display a block indicating the user that JS is turned off.

hope this will help

Why do package names often begin with "com"

  • com => domain
  • something => company name
  • something => Main package name

For example: com.paresh.mainpackage

Companies use their reversed Internet domain name to begin their package names—for example, com.example.mypackage for a package named mypackage created by a programmer at example.com. This information i have found at http://download.oracle.com/javase/tutorial/java/package/namingpkgs.html

nano error: Error opening terminal: xterm-256color

You can add the following in your .bashrc

if [ "$TERM" = xterm ]; then TERM=xterm-256color; fi

Getting the index of the returned max or min item using max()/min() on a list

Simple as that :

stuff = [2, 4, 8, 15, 11]

index = stuff.index(max(stuff))

How to access JSON Object name/value?

Try this code..

function (data) {


var json = jQuery.parseJSON(data);
alert( json.name );


}

Combine two tables for one output

In your expected output, you've got the second last row sum incorrect, it should be 40 according to the data in your tables, but here is the query:

Select  ChargeNum, CategoryId, Sum(Hours)
From    (
    Select  ChargeNum, CategoryId, Hours
    From    KnownHours
    Union
    Select  ChargeNum, 'Unknown' As CategoryId, Hours
    From    UnknownHours
) As a
Group By ChargeNum, CategoryId
Order By ChargeNum, CategoryId

And here is the output:

ChargeNum  CategoryId 
---------- ---------- ----------------------
111111     1          40
111111     2          50
111111     Unknown    70
222222     1          40
222222     Unknown    25.5

Resize an Array while keeping current elements in Java?

You could just use ArrayList which does the job for you.

How to solve npm install throwing fsevents warning on non-MAC OS?

Switch to PNPM: https://pnpm.js.org/

The fsevents warnings are gone (on Linux).

Even the latest yarn (2.x) shows the warnings.

Is there a command to restart computer into safe mode?

My first answer!

This will set the safemode switch:

bcdedit /set {current} safeboot minimal 

with networking:

bcdedit /set {current} safeboot network

then reboot the machine with

shutdown /r

to put back in normal mode via dos:

bcdedit /deletevalue {current} safeboot

Ansible: get current target host's IP address

If you want the external public IP and you're in a cloud environment like AWS or Azure, you can use the ipify_facts module:

# TODO: SECURITY: This requires that we trust ipify to provide the correct public IP. We could run our own ipify server.
- name: Get my public IP from ipify.org
  ipify_facts:

This will place the public IP into the variable ipify_public_ip.

Flutter.io Android License Status Unknown

Here's what I did to fix my issue. Please note that, you don't have to uninstall your old copy of Android Studio/SDK. Android Studio will take care of that whilst you are installing the latest version.

  1. Downloaded & install the latest version of Android Studio
  2. Follow the instructions in this tutorial
  3. Once the installation is complete, run flutter doctor and check, your issue should have been resolved. If the issue is resolved, there's no need to run the flutter doctor --android-licenses command.

Reset IntelliJ UI to Default

All above answers are correct, but you loose configuration settings.

But if your IDE's only themes or fonts are changed or some UI related issues and you want to restore to default theme, then just delete

${user.home}/.IntelliJIdea13/config/options/options.xml

file while IDE is not running, then after next restart IDE's theme will gets reset to default.

How to check if a registry value exists using C#?

public bool ValueExists(RegistryKey Key, string Value)
{
   try
   {
       return Key.GetValue(Value) != null;
   }
   catch
   {
       return false;
   }
}

This simple function will return true only if a value is found but it is not null, else will return false if the value exists but it is null or the value doesn't exists in the key.


USAGE for your question:

if (ValueExists(winLogonKey, "Start")
{
    // The values exists
}
else
{
    // The values does not exists
}

How to compare datetime with only date in SQL Server

You can use LIKE statement instead of =. But to do this with DateStamp you need to CONVERT it first to VARCHAR:

SELECT * 
FROM [User] U
WHERE CONVERT(VARCHAR, U.DateCreated, 120) LIKE '2014-02-07%'

Add a linebreak in an HTML text area

You could use \r\n, or System.Environment.NewLine.

Using AES encryption in C#

You can use password from text box like key... With this code you can encrypt/decrypt text, picture, word document, pdf....

 public class Rijndael
{
    private byte[] key;
    private readonly byte[] vector = { 255, 64, 191, 111, 23, 3, 113, 119, 231, 121, 252, 112, 79, 32, 114, 156 };

    ICryptoTransform EnkValue, DekValue;

    public Rijndael(byte[] key)
    {
        this.key = key;
        RijndaelManaged rm = new RijndaelManaged();
        rm.Padding = PaddingMode.PKCS7;
        EnkValue = rm.CreateEncryptor(key, vector);
        DekValue = rm.CreateDecryptor(key, vector);
    }

    public byte[] Encrypt(byte[] byte)
    {

        byte[] enkByte= byte;
        byte[] enkNewByte;
        using (MemoryStream ms = new MemoryStream())
        {
            using (CryptoStream cs = new CryptoStream(ms, EnkValue, CryptoStreamMode.Write))
            {
                cs.Write(enkByte, 0, enkByte.Length);
                cs.FlushFinalBlock();

                ms.Position = 0;
                enkNewByte= new byte[ms.Length];
                ms.Read(enkNewByte, 0, enkNewByte.Length);
            }
        }
        return enkNeyByte;
    }

    public byte[] Dekrypt(byte[] enkByte)
    {
        byte[] dekByte;
        using (MemoryStream ms = new MemoryStream())
        {
            using (CryptoStream cs = new CryptoStream(ms, DekValue, CryptoStreamMode.Write))
            {
                cs.Write(enkByte, 0, enkByte.Length);
                cs.FlushFinalBlock();

                ms.Position = 0;
                dekByte= new byte[ms.Length];
                ms.Read(dekByte, 0, dekByte.Length);
            }
        }
        return dekByte;
    }
}

Convert password from text box to byte array...

private byte[] ConvertPasswordToByte(string password)
    {
        byte[] key = new byte[32];
        for (int i = 0; i < passwprd.Length; i++)
        {
            key[i] = Convert.ToByte(passwprd[i]);
        }
        return key;
    }

No log4j2 configuration file found. Using default configuration: logging only errors to the console

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
  <PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level %logger{36} - %msg%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="DEBUG">
  <AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
  1. Create a new Text document and copy-paste the above code and save it as log4j2.xml.

  2. Now copy this log4j2.xml file and paste it under your src folder of your Java project.

  3. Run your java program again, you will see error is gone.

Add and Remove Views in Android Dynamically?

//MainActivity :





 package com.edittext.demo;
    import android.app.Activity;
    import android.os.Bundle;
    import android.text.TextUtils;
    import android.view.Menu;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.LinearLayout;
    import android.widget.Toast;

    public class MainActivity extends Activity {

        private EditText edtText;
        private LinearLayout LinearMain;
        private Button btnAdd, btnClear;
        private int no;

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

            edtText = (EditText)findViewById(R.id.edtMain);
            btnAdd = (Button)findViewById(R.id.btnAdd);
            btnClear = (Button)findViewById(R.id.btnClear);
            LinearMain = (LinearLayout)findViewById(R.id.LinearMain);

            btnAdd.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {
                    if (!TextUtils.isEmpty(edtText.getText().toString().trim())) {
                        no = Integer.parseInt(edtText.getText().toString());
                        CreateEdittext();
                    }else {
                        Toast.makeText(MainActivity.this, "Please entere value", Toast.LENGTH_SHORT).show();
                    }
                }
            });

            btnClear.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {
                    LinearMain.removeAllViews();
                    edtText.setText("");
                }
            });

            /*edtText.addTextChangedListener(new TextWatcher() {
                @Override
                public void onTextChanged(CharSequence s, int start, int before, int count) {

                }
                @Override
                public void beforeTextChanged(CharSequence s, int start, int count,int after) {
                }
                @Override
                public void afterTextChanged(Editable s) {
                }
            });*/

        }

        protected void CreateEdittext() {
            final EditText[] text = new EditText[no];
            final Button[] add = new Button[no];
            final LinearLayout[] LinearChild = new LinearLayout[no];
            LinearMain.removeAllViews();

            for (int i = 0; i < no; i++){

                View view = getLayoutInflater().inflate(R.layout.edit_text, LinearMain,false);
                text[i] = (EditText)view.findViewById(R.id.edtText);
                text[i].setId(i);
                text[i].setTag(""+i);

                add[i] = (Button)view.findViewById(R.id.btnAdd);
                add[i].setId(i);
                add[i].setTag(""+i);

                LinearChild[i] = (LinearLayout)view.findViewById(R.id.child_linear);
                LinearChild[i].setId(i);
                LinearChild[i].setTag(""+i);

                LinearMain.addView(view);

                add[i].setOnClickListener(new View.OnClickListener() {
                    public void onClick(View v) {
                        //Toast.makeText(MainActivity.this, "add text "+v.getTag(), Toast.LENGTH_SHORT).show();
                        int a = Integer.parseInt(text[v.getId()].getText().toString());
                        LinearChild[v.getId()].removeAllViews();
                        for (int k = 0; k < a; k++){

                            EditText text = (EditText) new EditText(MainActivity.this);
                            text.setId(k);
                            text.setTag(""+k);

                            LinearChild[v.getId()].addView(text);
                        }
                    }
                });
            }
        }

        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.main, menu);
            return true;
        }

    }

// Now add xml main

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity" >

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:orientation="horizontal" >

    <EditText
        android:id="@+id/edtMain"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:layout_weight="1"
        android:ems="10"
        android:hint="Enter value" >

        <requestFocus />
    </EditText>

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:text="Add" />

    <Button
        android:id="@+id/btnClear"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:layout_marginRight="5dp"
        android:text="Clear" />
</LinearLayout>

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_margin="10dp" >

    <LinearLayout
        android:id="@+id/LinearMain"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical" >
    </LinearLayout>
</ScrollView>

// now add view xml file..

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:orientation="horizontal" >

    <EditText
        android:id="@+id/edtText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="20dp"
        android:ems="10" />

    <Button
        android:id="@+id/btnAdd"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="10dp"
        android:text="Add" />
</LinearLayout>

<LinearLayout
    android:id="@+id/child_linear"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginLeft="30dp"
    android:layout_marginRight="10dp"
    android:layout_marginTop="5dp"
    android:orientation="vertical" >
</LinearLayout>

How to override maven property in command line?

See Introduction to the POM

finalName is created as:

<build>
    <finalName>${project.artifactId}-${project.version}</finalName>
</build>

One of the solutions is to add own property:

<properties>
    <finalName>${project.artifactId}-${project.version}</finalName>
</properties>
<build>
    <finalName>${finalName}</finalName>
 </build>

And now try:

mvn -DfinalName=build clean package

convert iso date to milliseconds in javascript

Another possible solution is to compare current date with January 1, 1970, you can get January 1, 1970 by new Date(0);

var date = new Date(); 
var myDate= date - new Date(0);

php - How do I fix this illegal offset type error

Illegal offset type errors occur when you attempt to access an array index using an object or an array as the index key.

Example:

$x = new stdClass();
$arr = array();
echo $arr[$x];
//illegal offset type

Your $xml array contains an object or array at $xml->entry[$i]->source for some value of $i, and when you try to use that as an index key for $s, you get that warning. You'll have to make sure $xml contains what you want it to and that you're accessing it correctly.

Construct a manual legend for a complicated plot

In case you were struggling to change linetypes, the following answer should be helpful. (This is an addition to the solution by Andy W.)

We will try to extend the learned pattern:

cols <- c("LINE1"="#f04546","LINE2"="#3591d1","BAR"="#62c76b")
line_types <- c("LINE1"=1,"LINE2"=3)
ggplot(data=data,aes(x=a)) + 
  geom_bar(stat="identity", aes(y=h,fill = "BAR"))+ #green
  geom_line(aes(y=b,group=1, colour="LINE1", linetype="LINE1"),size=0.5) +   #red
  geom_point(aes(y=b, colour="LINE1", fill="LINE1"),size=2) +           #red
  geom_line(aes(y=c,group=1,colour="LINE2", linetype="LINE2"),size=0.5) +   #blue 
  geom_point(aes(y=c,colour="LINE2", fill="LINE2"),size=2) +           #blue
  scale_colour_manual(name="Error Bars",values=cols, 
                  guide = guide_legend(override.aes=aes(fill=NA))) + 
  scale_linetype_manual(values=line_types)+
  scale_fill_manual(name="Bar",values=cols, guide="none") +
  ylab("Symptom severity") + xlab("PHQ-9 symptoms") +
  ylim(0,1.6) +
  theme_bw() +
  theme(axis.title.x = element_text(size = 15, vjust=-.2)) +
  theme(axis.title.y = element_text(size = 15, vjust=0.3))

However, what we get is the following result: manual without name

The problem is that the linetype is not merged in the main legend. Note that we did not give any name to the method scale_linetype_manual. The trick which works here is to give it the same name as what you used for naming scale_colour_manual. More specifically, if we change the corresponding line to the following we get the desired result:

scale_linetype_manual(name="Error Bars",values=line_types)

manual with the same name

Now, it is easy to change the size of the line with the same idea.

Note that the geom_bar has not colour property anymore. (I did not try to fix this issue.) Also, adding geom_errorbar with colour attribute spoils the result. It would be great if somebody can come up with a better solution which resolves these two issues as well.

Refresh a page using PHP

Besides all the PHP ways to refresh a page, the page will also be refreshed with the following HTML meta tag:

<meta http-equiv="refresh" content="5">

See Meta refresh - "automatically refresh the current web page or frame after a given time interval"

You can set the time within the content value.

How to access remote server with local phpMyAdmin client?

Just add below lines to your /etc/phpmyadmin/config.inc.php file in the bottom:

$i++;
$cfg['Servers'][$i]['host'] = 'HostName:port'; //provide hostname and port if other than default
$cfg['Servers'][$i]['user'] = 'userName';   //user name for your remote server
$cfg['Servers'][$i]['password'] = 'Password';  //password
$cfg['Servers'][$i]['auth_type'] = 'config';       // keep it as config

You will get Current Server: drop down with both 127.0.0.1 and one what you have provided with $cfg['Servers'][$i]['host'] can switch between the servers.

More Details: http://sforsuresh.in/access-remote-mysql-server-using-local-phpmyadmin/

How to remove all listeners in an element?

Here's a function that is also based on cloneNode, but with an option to clone only the parent node and move all the children (to preserve their event listeners):

function recreateNode(el, withChildren) {
  if (withChildren) {
    el.parentNode.replaceChild(el.cloneNode(true), el);
  }
  else {
    var newEl = el.cloneNode(false);
    while (el.hasChildNodes()) newEl.appendChild(el.firstChild);
    el.parentNode.replaceChild(newEl, el);
  }
}

Remove event listeners on one element:

recreateNode(document.getElementById("btn"));

Remove event listeners on an element and all of its children:

recreateNode(document.getElementById("list"), true);

If you need to keep the object itself and therefore can't use cloneNode, then you have to wrap the addEventListener function and track the listener list by yourself, like in this answer.

How to enable curl in Wamp server

Left Click on the WAMP icon the system try -> PHP -> PHP Extensions -> Enable php_curl

How do I list the symbols in a .so file

You can use the nm -g tool from the binutils toolchain. However, their source is not always readily available. and I'm not actually even sure that this information can always be retrieved. Perhaps objcopy reveals further information.

/EDIT: The tool's name is of course nm. The flag -g is used to show only exported symbols.

Which is the preferred way to concatenate a string in Python?

You can do in different ways.

str1 = "Hello"
str2 = "World"
str_list = ['Hello', 'World']
str_dict = {'str1': 'Hello', 'str2': 'World'}

# Concatenating With the + Operator
print(str1 + ' ' + str2)  # Hello World

# String Formatting with the % Operator
print("%s %s" % (str1, str2))  # Hello World

# String Formatting with the { } Operators with str.format()
print("{}{}".format(str1, str2))  # Hello World
print("{0}{1}".format(str1, str2))  # Hello World
print("{str1} {str2}".format(str1=str_dict['str1'], str2=str_dict['str2']))  # Hello World
print("{str1} {str2}".format(**str_dict))  # Hello World

# Going From a List to a String in Python With .join()
print(' '.join(str_list))  # Hello World

# Python f'strings --> 3.6 onwards
print(f"{str1} {str2}")  # Hello World

I created this little summary through following articles.

Pandas concat: ValueError: Shape of passed values is blah, indices imply blah2

To drop duplicate indices, use df = df.loc[df.index.drop_duplicates()]. C.f. pandas.pydata.org/pandas-docs/stable/generated/… – BallpointBen Apr 18 at 15:25

This is wrong but I can't reply directly to BallpointBen's comment due to low reputation. The reason its wrong is that df.index.drop_duplicates() returns a list of unique indices, but when you index back into the dataframe using those the unique indices it still returns all records. I think this is likely because indexing using one of the duplicated indices will return all instances of the index.

Instead, use df.index.duplicated(), which returns a boolean list (add the ~ to get the not-duplicated records):

df = df.loc[~df.index.duplicated()]

Recursively find files with a specific extension

find -name "*Robert*" \( -name "*.pdf" -o -name "*.jpg" \)

The -o repreents an OR condition and you can add as many as you wish within the braces. So this says to find all files containing the word "Robert" anywhere in their names and whose names end in either "pdf" or "jpg".

The apk must be signed with the same certificates as the previous version

My [silly] mistake was that i used app-debug.apk file instead of app-release.apk file. You need to to choose "release" in "Build Variants" frame when you generate signed APK. The app-release.apk file should be located under "app\release" folder in your project root.

How do I get a reference to the app delegate in Swift?

it is very simple

App delegate instance

let app = UIApplication.shared.delegate as! AppDelegate

you can call a method with one line syntax

app.callingMethod()

you can access a variable with this code

app.yourVariable = "Assigning a value"

JAXB :Need Namespace Prefix to all the elements

MSK,

Have you tried setting a namespace declaration to your member variables like this? :

@XmlElement(required = true, namespace = "http://example.com/a")
protected String username;

@XmlElement(required = true, namespace = "http://example.com/a")
protected String password;

For our project, it solved namespace issues. We also had to create NameSpacePrefixMappers.

Can't bind to 'ngForOf' since it isn't a known property of 'tr' (final release)

In my case, the issue was that my teammate mentioned *ngfor in templates instead of *ngFor. Strange that there is no correct error to handle this issue (In Angular 4).

C# HttpWebRequest of type "application/x-www-form-urlencoded" - how to send '&' character in content body?

First install "Microsoft ASP.NET Web API Client" nuget package:

  PM > Install-Package Microsoft.AspNet.WebApi.Client

Then use the following function to post your data:

public static async Task<TResult> PostFormUrlEncoded<TResult>(string url, IEnumerable<KeyValuePair<string, string>> postData)
{
    using (var httpClient = new HttpClient())
    {
        using (var content = new FormUrlEncodedContent(postData))
        {
            content.Headers.Clear();
            content.Headers.Add("Content-Type", "application/x-www-form-urlencoded");

            HttpResponseMessage response = await httpClient.PostAsync(url, content);

            return await response.Content.ReadAsAsync<TResult>();
        }
    }
}

And this is how to use it:

TokenResponse tokenResponse = 
    await PostFormUrlEncoded<TokenResponse>(OAuth2Url, OAuth2PostData);

or

TokenResponse tokenResponse = 
    (Task.Run(async () 
        => await PostFormUrlEncoded<TokenResponse>(OAuth2Url, OAuth2PostData)))
        .Result

or (not recommended)

TokenResponse tokenResponse = 
    PostFormUrlEncoded<TokenResponse>(OAuth2Url, OAuth2PostData).Result;

How to delete a specific file from folder using asp.net

In my project i am using ajax and i create a web method in my code behind like this

in front

 $("#attachedfiles a").live("click", function () {
            var row = $(this).closest("tr");
            var fileName = $("td", row).eq(0).html();
            $.ajax({
                type: "POST",
                url: "SendEmail.aspx/RemoveFile",
                data: '{fileName: "' + fileName + '" }',
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function () { },
                failure: function (response) {
                    alert(response.d);
                }
            });
            row.remove();
        });  

in code behind

        [WebMethod]
        public static void RemoveFile(string fileName)
        {
            List<HttpPostedFile> files = (List<HttpPostedFile>)HttpContext.Current.Session["Files"];
            files.RemoveAll(f => f.FileName.ToLower().EndsWith(fileName.ToLower()));

            if (System.IO.File.Exists(HttpContext.Current.Server.MapPath("~/Employee/uploads/" + fileName)))
            {
                System.IO.File.Delete(HttpContext.Current.Server.MapPath("~/Employee/uploads/" + fileName));
            }
        }

i think this will help you.

What is Gradle in Android Studio?

Gradle is an automated build toolkit that can integrate into lots of different environments not only for Android projects.

Here are few things that you can do with gradle.

  • Minimal Configuration Required for New Projects because Gradle has defaults configurations for your android studio projects.

  • Dependancy Declaration. You can declare dependency jar files or library files that is hosted in local or remote server.

  • Gradle automatically generates a test directory and a test APK from your project's source.

  • If you add all the necessary information, such as keyPassword and keyAlias, to your Gradle build file, you can use Gradle to generate signed APKs.

  • Gradle can generate multiple APKs with different package and build configurations from a single module.

What is the difference between README and README.md in GitHub projects?

.md stands for markdown and is generated at the bottom of your github page as html.

Typical syntax includes:

Will become a heading
==============

Will become a sub heading
--------------

*This will be Italic*

**This will be Bold**

- This will be a list item
- This will be a list item

    Add a indent and this will end up as code

For more details: http://daringfireball.net/projects/markdown/

Best practice for using assert?

Both the use of assert and the raising of exceptions are about communication.

  • Assertions are statements about the correctness of code addressed at developers: An assertion in the code informs readers of the code about conditions that have to be fulfilled for the code being correct. An assertion that fails at run-time informs developers that there is a defect in the code that needs fixing.

  • Exceptions are indications about non-typical situations that can occur at run-time but can not be resolved by the code at hand, addressed at the calling code to be handled there. The occurence of an exception does not indicate that there is a bug in the code.

Best practice

Therefore, if you consider the occurence of a specific situation at run-time as a bug that you would like to inform the developers about ("Hi developer, this condition indicates that there is a bug somewhere, please fix the code.") then go for an assertion. If the assertion checks input arguments of your code, you should typically add to the documentation that your code has "undefined behaviour" when the input arguments violate that conditions.

If instead the occurrence of that very situation is not an indication of a bug in your eyes, but instead a (maybe rare but) possible situation that you think should rather be handled by the client code, raise an exception. The situations when which exception is raised should be part of the documentation of the respective code.

Is there a performance [...] issue with using assert

The evaluation of assertions takes some time. They can be eliminated at compile time, though. This has some consequences, however, see below.

Is there a [...] code maintenance issue with using assert

Normally assertions improve the maintainability of the code, since they improve readability by making assumptions explicit and during run-time regularly verifying these assumptions. This will also help catching regressions. There is one issue, however, that needs to be kept in mind: Expressions used in assertions should have no side-effects. As mentioned above, assertions can be eliminated at compile time - which means that also the potential side-effects would disappear. This can - unintendedly - change the behaviour of the code.

XSL substring and indexOf

I want to select the text of a string that is located after the occurrence of substring

You could use:

substring-after($string,$match)

If you want a subtring of the above with some length then use:

substring(substring-after($string,$match),1,$length)

But problems begin if there is no ocurrence of the matching substring... So, if you want a substring with specific length located after the occurrence of a substring, or from the whole string if there is no match, you could use:

substring(substring-after($string,substring-before($string,$match)),
          string-length($match) * contains($string,$match) + 1,
          $length) 

Hidden property of a button in HTML

<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4/jquery.min.js"></script>
<script>

function showButtons () { $('#b1, #b2, #b3').show(); }

</script>
<style type="text/css">
#b1, #b2, #b3 {
display: none;
}

</style>
</head>
<body>

<a href="#" onclick="showButtons();">Show me the money!</a>

<input type="submit" id="b1" value="B1" />
<input type="submit" id="b2" value="B2"/>
<input type="submit" id="b3" value="B3" />

</body>
</html>

How to get hex color value rather than RGB value?

Try

// c - color str e.g."rgb(12,233,43)", result color hex e.g. "#0ce92b"
let rgb2hex= c=> '#'+c.match(/\d+/g).map(x=>(+x).toString(16).padStart(2,0)).join``

_x000D_
_x000D_
// rgb - color str e.g."rgb(12,233,43)", result color hex e.g. "#0ce92b"_x000D_
let rgb2hex= c=> '#'+c.match(/\d+/g).map(x=>(+x).toString(16).padStart(2,0)).join``_x000D_
_x000D_
console.log(rgb2hex("rgb(12,233,43"));
_x000D_
_x000D_
_x000D_

Generate a sequence of numbers in Python

Includes some guessing on the exact sequence you are expecting:

>>> l = list(range(1, 100, 4)) + list(range(2, 100, 4))
>>> l.sort()
>>> ','.join(map(str, l))
'1,2,5,6,9,10,13,14,17,18,21,22,25,26,29,30,33,34,37,38,41,42,45,46,49,50,53,54,57,58,61,62,65,66,69,70,73,74,77,78,81,82,85,86,89,90,93,94,97,98'

As one-liner:

>>> ','.join(map(str, sorted(list(range(1, 100, 4))) + list(range(2, 100, 4))))

(btw. this is Python 3 compatible)

How to display a PDF via Android web browser without "downloading" first

You can open PDF in Google Docs Viewer by appending URL to:

http://docs.google.com/gview?embedded=true&url=<url of a supported doc>

This would open PDF in default browser or a WebView.

A list of supported formats is given here.

Regular expression to stop at first match

location="(.*)" will match from the " after location= until the " after some="xxx unless you make it non-greedy. So you either need .*? (i.e. make it non-greedy) or better replace .* with [^"]*.

jQuery send HTML data through POST

_x000D_
_x000D_
jQuery.post(post_url,{ content: "John" } )_x000D_
 .done(function( data ) {_x000D_
   _x000D_
   _x000D_
 });_x000D_
 
_x000D_
_x000D_
_x000D_

I used the technique what u have replied above, it works fine but my problem is i need to generate a pdf conent using john as text . I have been able to echo the passed data. but getting empty in when generating pdf uisng below content ples check

_x000D_
_x000D_
ob_start();_x000D_
        _x000D_
   include_once(JPATH_SITE .'/components/com_gaevents/pdfgenerator.php');_x000D_
   $content = ob_get_clean();_x000D_
   _x000D_
  _x000D_
  _x000D_
    $test = $_SESSION['content'] ;_x000D_
  _x000D_
   require_once(JPATH_SITE.'/html2pdf/html2pdf.class.php');_x000D_
            $html2pdf = new HTML2PDF('P', 'A4', 'en', true, 'UTF-8',0 );   _x000D_
    $html2pdf->setDefaultFont('Arial');_x000D_
    $html2pdf->WriteHTML($test);
_x000D_
_x000D_
_x000D_

Search and get a line in Python

items=re.findall("token.*$",s,re.MULTILINE)
>>> for x in items:

you can also get the line if there are other characters before token

items=re.findall("^.*token.*$",s,re.MULTILINE)

The above works like grep token on unix and keyword 'in' or .contains in python and C#

s='''
qwertyuiop
asdfghjkl

zxcvbnm
token qwerty

asdfghjklñ
'''

http://pythex.org/ matches the following 2 lines

....
....
token qwerty

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

The problem is that the true y is binary (zeros and ones), while your predictions are not. You probably generated probabilities and not predictions, hence the result :) Try instead to generate class membership, and it should work!

How do I use the Tensorboard callback of Keras?

This is how you use the TensorBoard callback:

from keras.callbacks import TensorBoard

tensorboard = TensorBoard(log_dir='./logs', histogram_freq=0,
                          write_graph=True, write_images=False)
# define model
model.fit(X_train, Y_train,
          batch_size=batch_size,
          epochs=nb_epoch,
          validation_data=(X_test, Y_test),
          shuffle=True,
          callbacks=[tensorboard])

String contains another two strings

I just checked for a space in contains to check if the string has 2 or more words.

string d = "You hit someone for 50 damage";
string a = "damage";
string b = "someone";
string c = "you";

bool a = ?(d.contains(" ")):true:false;

if(a)
{
 Console.WriteLine(" " + d);
}

Console.Read();

Replace \n with actual new line in Sublime Text

None of the above worked for me in Sublime Text 2 on Windows.

I did this:

  • click on an empty line;
  • drag to the following empty line (selecting the invisible character after the line);
  • press ctrl+H for replace;
  • input desired replacement character/string or leave it empty;
  • click "Replace all";

By selecting before hitting ctrl+H it uses that as the character to be replaced.

Is it possible to make Font Awesome icons larger than 'fa-5x'?

  1. Just add the font awesome class like this:

    class="fa fa-plus-circle fa-3x"
    

    (You can increase the size as per 5x, 7x, 9x..)

  2. You can also add custom CSS.

Left function in c#

Just write what you really wanted to know:

fac.GetCachedValue("Auto Print Clinical Warnings").ToLower().StartsWith("y")

It's much simpler than anything with substring.

Rails ActiveRecord date between

I would personally created a scope to make it more readable and re-usable:

In you Comment.rb, you can define a scope:

scope :created_between, lambda {|start_date, end_date| where("created_at >= ? AND created_at <= ?", start_date, end_date )}

Then to query created between:

@comment.created_between(1.year.ago, Time.now)

Hope it helps.

Why am I getting "IndentationError: expected an indented block"?

This is just an indentation problem since Python is very strict when it comes to it.

If you are using Sublime, you can select all, click on the lower right beside 'Python' and make sure you check 'Indent using spaces' and choose your Tab Width to be consistent, then Convert Indentation to Spaces to convert all tabs to spaces.

What is the difference between Step Into and Step Over in a debugger

Consider the following code with your current instruction pointer (the line that will be executed next, indicated by ->) at the f(x) line in g(), having been called by the g(2) line in main():

public class testprog {
    static void f (int x) {
        System.out.println ("num is " + (x+0)); // <- STEP INTO
    }

    static void g (int x) {
->      f(x); //
        f(1); // <----------------------------------- STEP OVER
    }

    public static void main (String args[]) {
        g(2);
        g(3); // <----------------------------------- STEP OUT OF
    }
}

If you were to step into at that point, you will move to the println() line in f(), stepping into the function call.

If you were to step over at that point, you will move to the f(1) line in g(), stepping over the function call.

Another useful feature of debuggers is the step out of or step return. In that case, a step return will basically run you through the current function until you go back up one level. In other words, it will step through f(x) and f(1), then back out to the calling function to end up at g(3) in main().

Loading/Downloading image from URL on Swift

Swift 4::

This will shows loader while loading the image. You can use NSCache which store image temporarily

let imageCache = NSCache<NSString, UIImage>()
extension UIImageView {
    func loadImageUsingCache(withUrl urlString : String) {
        let url = URL(string: urlString)
        if url == nil {return}
        self.image = nil

        // check cached image
        if let cachedImage = imageCache.object(forKey: urlString as NSString)  {
            self.image = cachedImage
            return
        }

        let activityIndicator: UIActivityIndicatorView = UIActivityIndicatorView.init(activityIndicatorStyle: .gray)
        addSubview(activityIndicator)
        activityIndicator.startAnimating()
        activityIndicator.center = self.center

        // if not, download image from url
        URLSession.shared.dataTask(with: url!, completionHandler: { (data, response, error) in
            if error != nil {
                print(error!)
                return
            }

            DispatchQueue.main.async {
                if let image = UIImage(data: data!) {
                    imageCache.setObject(image, forKey: urlString as NSString)
                    self.image = image
                    activityIndicator.removeFromSuperview()
                }
            }

        }).resume()
    }
}

Usage:-

truckImageView.loadImageUsingCache(withUrl: currentTruck.logoString)

Why does using an Underscore character in a LIKE filter give me all the results?

The underscore is the wildcard in a LIKE query for one arbitrary character.

Hence LIKE %_% means "give me all records with at least one arbitrary character in this column".

You have to escape the wildcard character, in sql-server with [] around:

SELECT m.* 
FROM Manager m 
WHERE m.managerid    LIKE  '[_]%'
AND   m.managername  LIKE '%[_]%'

See: LIKE (Transact-SQL)

Demo

Finding an item in a List<> using C#

item = objects.Find(obj => obj.property==myValue);

Call php function from JavaScript

I recently published a jQuery plugin which allows you to make PHP function calls in various ways: https://github.com/Xaxis/jquery.php

Simple example usage:

// Both .end() and .data() return data to variables
var strLenA = P.strlen('some string').end();
var strLenB = P.strlen('another string').end();
var totalStrLen = strLenA + strLenB;
console.log( totalStrLen ); // 25

// .data Returns data in an array
var data1 = P.crypt("Some Crypt String").data();
console.log( data1 ); // ["$1$Tk1b01rk$shTKSqDslatUSRV3WdlnI/"]

c# dictionary How to add multiple values for single key?

Here are many variations of the one answer :) My is another one and it uses extension mechanism as comfortable way to execute (handy):

public static void AddToList<T, U>(this IDictionary<T, List<U>> dict, T key, U elementToList)
{

    List<U> list;

    bool exists = dict.TryGetValue(key, out list);

    if (exists)
    {
        dict[key].Add(elementToList);
    }
    else
    {
        dict[key] = new List<U>();
        dict[key].Add(elementToList);
    }

}

Then you use it as follows:

Dictionary<int, List<string>> dict = new Dictionary<int, List<string>>();

dict.AddToList(4, "test1");
dict.AddToList(4, "test2");
dict.AddToList(4, "test3");

dict.AddToList(5, "test4");

How do I access refs of a child component in the parent component

First access the children with: this.props.children, each child will then have its ref as a property on it.

`col-xs-*` not working in Bootstrap 4

If you want to apply an extra small class in Bootstrap 4,you need to use col-. important thing to know is that col-xs- is dropped in Bootstrap4

What is the difference between atan and atan2 in C++?

std::atan2 allows calculating the arctangent of all four quadrants. std::atan only allows calculating from quadrants 1 and 4.

What is the minimum I have to do to create an RPM file?

For quick RPM building, check out Togo:

https://github.com/genereese/togo-rpm

The project has a Quick-Start guide and I was able to create a basic RPM in less than 3 minutes.

Example using the data provided in the original question:

1) Create the project directory using the script:

$ togo project create foobar; cd foobar

2) Make your desired directory structure under ./root and copy your files into it:

$ mkdir -p root/etc; cp /path/to/foobar.conf root/etc/
$ mkdir -p root/usr/bin; cp /path/to/foobar root/usr/bin/

3) Exclude system-owned directories from your RPM's ownership:

$ togo file exclude root/etc root/usr/bin

4) (OPTIONAL) Modify the generated spec to change your package description/dependencies/version/whatever, etc.:

$ vi spec/header

5) Build the RPM:

$ togo build package

-and your RPM is spit out into the ./rpms directory.

how to output every line in a file python

You probably want something like:

if data.find('!masters') != -1:
     f = open('masters.txt')
     lines = f.read().splitlines()
     f.close()
     for line in lines:
         print line
         sck.send('PRIVMSG ' + chan + " " + str(line) + '\r\n')

Don't close it every iteration of the loop and print line instead of lines. Also use readlines to get all the lines.

EDIT removed my other answer - the other one in this discussion is a better alternative than what I had, so there's no reason to copy it.

Also stripped off the \n with read().splitlines()

How to Code Double Quotes via HTML Codes

Google recommend that you don't use any of them, source.

There is no need to use entity references like &mdash, &rdquo, or &#x263a, assuming the same encoding (UTF-8) is used for files and editors as well as among teams.

Is there a reason you can't simply use "?

System.drawing namespace not found under console application

If you are using Visual Studio 2010 or plus then check the target framework that is it .Net Framework 4.0 or .Net Framework 4.0 Client Profile. then change is to .Net Framework 4.0.

You need to add reference this .dll file (System.Drawing.dll) to perform drawing operations.

If it is OK then follow these steps to add reference to System.Drawing.dll

  1. In Solution Explorer, right-click on the project node and click Add Reference.
  2. In the Add Reference dialog box, select the tab indicating the type of component you want to reference.
  3. Select the System.Drawing.dll to reference, then click OK.

How to enable MySQL Query Log?

To enable the query log in MAC Machine:

Open the following file:

vi /private/etc/my.cnf

Set the query log url under 'mysqld' section as follows:

[mysqld]

general_log_file=/Users/kumanan/Documents/mysql_query.log

Few machine’s are not logging query properly, So that case you can enable it from MySQL console

mysql> SET global general_log = 1;

Difference between "read commited" and "repeatable read"

Old question which has an accepted answer already, but I like to think of these two isolation levels in terms of how they change the locking behavior in SQL Server. This might be helpful for those who are debugging deadlocks like I was.

READ COMMITTED (default)

Shared locks are taken in the SELECT and then released when the SELECT statement completes. This is how the system can guarantee that there are no dirty reads of uncommitted data. Other transactions can still change the underlying rows after your SELECT completes and before your transaction completes.

REPEATABLE READ

Shared locks are taken in the SELECT and then released only after the transaction completes. This is how the system can guarantee that the values you read will not change during the transaction (because they remain locked until the transaction finishes).

Git resolve conflict using --ours/--theirs for all files

You can -Xours or -Xtheirs with git merge as well. So:

  1. abort the current merge (for instance with git reset --hard HEAD)
  2. merge using the strategy you prefer (git merge -Xours or git merge -Xtheirs)

DISCLAIMER: of course you can choose only one option, either -Xours or -Xtheirs, do use different strategy you should of course go file by file.

I do not know if there is a way for checkout, but I do not honestly think it is terribly useful: selecting the strategy with the checkout command is useful if you want different solutions for different files, otherwise just go for the merge strategy approach.

Convert Python dict into a dataframe

As explained on another answer using pandas.DataFrame() directly here will not act as you think.

What you can do is use pandas.DataFrame.from_dict with orient='index':

In[7]: pandas.DataFrame.from_dict({u'2012-06-08': 388,
 u'2012-06-09': 388,
 u'2012-06-10': 388,
 u'2012-06-11': 389,
 u'2012-06-12': 389,
 .....
 u'2012-07-05': 392,
 u'2012-07-06': 392}, orient='index', columns=['foo'])
Out[7]: 
            foo
2012-06-08  388
2012-06-09  388
2012-06-10  388
2012-06-11  389
2012-06-12  389
........
2012-07-05  392
2012-07-06  392

posting hidden value

Maybe a little late to the party but why don't you use sessions to store your data?

bookingfacilities.php

session_start();
$_SESSION['form_date'] = $date;

successfulbooking.php

session_start();
$date = $_SESSION['form_date']; 

Nobody will see this.

Get Date Object In UTC format in Java

You can subtract the time zone difference from now.

final Calendar calendar  = Calendar.getInstance();
final int      utcOffset = calendar.get(Calendar.ZONE_OFFSET) + calendar.get(Calendar.DST_OFFSET);
final long     tempDate  = new Date().getTime();

return new Date(tempDate - utcOffset);

How to place a div on the right side with absolute position

For top right corner try this:

position: absolute;
top: 0;
right: 0;

stopPropagation vs. stopImmediatePropagation

From the jQuery API:

In addition to keeping any additional handlers on an element from being executed, this method also stops the bubbling by implicitly calling event.stopPropagation(). To simply prevent the event from bubbling to ancestor elements but allow other event handlers to execute on the same element, we can use event.stopPropagation() instead.

Use event.isImmediatePropagationStopped() to know whether this method was ever called (on that event object).

In short: event.stopPropagation() allows other handlers on the same element to be executed, while event.stopImmediatePropagation() prevents every event from running.

Creating an object: with or without `new`

The first allocates an object with automatic storage duration, which means it will be destructed automatically upon exit from the scope in which it is defined.

The second allocated an object with dynamic storage duration, which means it will not be destructed until you explicitly use delete to do so.

Convert web page to image

Not sure if this is what you want but this is what I do sometimes in a pinch when certain websites are not saving right.

I just print them to PDF and I get a PDF file of the 'print output'. There's an Microsoft XPS Document writer under my list of printers as well, but I don't use it.

Hope this helps! =)

Get DateTime.Now with milliseconds precision

If you still want a date instead of a string like the other answers, just add this extension method.

public static DateTime ToMillisecondPrecision(this DateTime d) {
    return new DateTime(d.Year, d.Month, d.Day, d.Hour, d.Minute,
                        d.Second, d.Millisecond, d.Kind);
}

How to install PyQt4 on Windows using pip?

Here are Windows wheel packages built by Chris Golke - Python Windows Binary packages - PyQt

In the filenames cp27 means C-python version 2.7, cp35 means python 3.5, etc.

Since Qt is a more complicated system with a compiled C++ codebase underlying the python interface it provides you, it can be more complex to build than just a pure python code package, which means it can be hard to install it from source.

Make sure you grab the correct Windows wheel file (python version, 32/64 bit), and then use pip to install it - e.g:

C:\path\where\wheel\is\> pip install PyQt4-4.11.4-cp35-none-win_amd64.whl

Should properly install if you are running an x64 build of Python 3.5.

Regular expression for matching latitude/longitude coordinates?

This one will strictly match latitude and longitude values that fall within the correct range:

^[-+]?([1-8]?\d(\.\d+)?|90(\.0+)?),\s*[-+]?(180(\.0+)?|((1[0-7]\d)|([1-9]?\d))(\.\d+)?)$

Matches

  • +90.0, -127.554334
  • 45, 180
  • -90, -180
  • -90.000, -180.0000
  • +90, +180
  • 47.1231231, 179.99999999

Doesn't Match

  • -90., -180.
  • +90.1, -100.111
  • -91, 123.456
  • 045, 180

How do I calculate a trendline for a graph?

Regarding a previous answer

if (B) y = offset + slope*x

then (C) offset = y/(slope*x) is wrong

(C) should be:

offset = y-(slope*x)

See: http://zedgraph.org/wiki/index.php?title=Trend

Trigger validation of all fields in Angular Form submit

You can use Angular-Validator to do what you want. It's stupid simple to use.

It will:

  • Only validate the fields on $dirty or on submit
  • Prevent the form from being submitted if it is invalid
  • Show custom error message after the field is $dirty or the form is submitted

See the demo

Example

<form angular-validator 
       angular-validator-submit="myFunction(myBeautifulForm)"
       name="myBeautifulForm">
       <!-- form fields here -->
    <button type="submit">Submit</button>
</form>

If the field does not pass the validator then the user will not be able to submit the form.

Check out angular-validator use cases and examples for more information.

Disclaimer: I am the author of Angular-Validator

Uninstall Django completely

Got it solved. I missed to delete the egg_info files of all previous Django versions. Removed them from /usr/local/lib/python2.7/dist-packages. Also from /usr/lib/python2.7/dist-packages (if any present here)

sudo pip freeze| grep Django
sudo pip show -f Django
sudo pip search Django | more +/^Django

All above commands should not show Django version to verify clean uninstallation.

MySQL ORDER BY multiple column ASC and DESC

group by default order by pk id,so the result
username point avg_time
demo123 100 90 ---> id = 4
demo123456 100 100 ---> id = 7
demo 90 120 ---> id = 1

How do I base64 encode a string efficiently using Excel VBA?

You can use the MSXML Base64 encoding functionality as described at www.nonhostile.com/howto-encode-decode-base64-vb6.asp:

Function EncodeBase64(text As String) As String
  Dim arrData() As Byte
  arrData = StrConv(text, vbFromUnicode)      

  Dim objXML As MSXML2.DOMDocument
  Dim objNode As MSXML2.IXMLDOMElement

  Set objXML = New MSXML2.DOMDocument 
  Set objNode = objXML.createElement("b64")

  objNode.dataType = "bin.base64"
  objNode.nodeTypedValue = arrData
  EncodeBase64 = objNode.Text 

  Set objNode = Nothing
  Set objXML = Nothing
End Function

How can I generate a random number in a certain range?

So you would want the following:

int random;
int max;
int min;

...somewhere in your code put the method to get the min and max from the user when they click submit and then use them in the following line of code:

random = Random.nextInt(max-min+1)+min;

This will set random to a random number between the user selected min and max. Then you will do:

TextView.setText(random.toString());

Angular 4 HttpClient Query Parameters

I ended up finding it through the IntelliSense on the get() function. So, I'll post it here for anyone who is looking for similar information.

Anyways, the syntax is nearly identical, but slightly different. Instead of using URLSearchParams() the parameters need to be initialized as HttpParams() and the property within the get() function is now called params instead of search.

import { HttpClient, HttpParams } from '@angular/common/http';
getLogs(logNamespace): Observable<any> {

    // Setup log namespace query parameter
    let params = new HttpParams().set('logNamespace', logNamespace);

    return this._HttpClient.get(`${API_URL}/api/v1/data/logs`, { params: params })
}

I actually prefer this syntax as its a little more parameter agnostic. I also refactored the code to make it slightly more abbreviated.

getLogs(logNamespace): Observable<any> {

    return this._HttpClient.get(`${API_URL}/api/v1/data/logs`, {
        params: new HttpParams().set('logNamespace', logNamespace)
    })
}

Multiple Parameters

The best way I have found thus far is to define a Params object with all of the parameters I want to define defined within. As @estus pointed out in the comment below, there are a lot of great answers in This Question as to how to assign multiple parameters.

getLogs(parameters) {

    // Initialize Params Object
    let params = new HttpParams();

    // Begin assigning parameters
    params = params.append('firstParameter', parameters.valueOne);
    params = params.append('secondParameter', parameters.valueTwo);

    // Make the API call using the new parameters.
    return this._HttpClient.get(`${API_URL}/api/v1/data/logs`, { params: params })

Multiple Parameters with Conditional Logic

Another thing I often do with multiple parameters is allow the use of multiple parameters without requiring their presence in every call. Using Lodash, it's pretty simple to conditionally add/remove parameters from calls to the API. The exact functions used in Lodash or Underscores, or vanilla JS may vary depending on your application, but I have found that checking for property definition works pretty well. The function below will only pass parameters that have corresponding properties within the parameters variable passed into the function.

getLogs(parameters) {

    // Initialize Params Object
    let params = new HttpParams();

    // Begin assigning parameters
    if (!_.isUndefined(parameters)) {
        params = _.isUndefined(parameters.valueOne) ? params : params.append('firstParameter', parameters.valueOne);
        params = _.isUndefined(parameters.valueTwo) ? params : params.append('secondParameter', parameters.valueTwo);
    }

    // Make the API call using the new parameters.
    return this._HttpClient.get(`${API_URL}/api/v1/data/logs`, { params: params })

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

De Morgan's laws allow us to convert disjunctions ("OR") into logical equivalents using only conjunctions ("AND") and negations ("NOT"). This means we can chain disjunctions ("OR") on to one line.

This means if name is "Yakko" or "Wakko" or "Dot", then echo "Warner brother or sister".

set warner=true
if not "%name%"=="Yakko" if not "%name%"=="Wakko" if not "%name%"=="Dot" set warner=false
if "%warner%"=="true" echo Warner brother or sister

This is another version of paxdiablo's "OR" example, but the conditions are chained on to one line. (Note that the opposite of leq is gtr, and the opposite of geq is lss.)

set res=true
if %hour% gtr 6 if %hour% lss 22 set res=false
if "%res%"=="true" set state=asleep

How can I explicitly free memory in Python?

As other answers already say, Python can keep from releasing memory to the OS even if it's no longer in use by Python code (so gc.collect() doesn't free anything) especially in a long-running program. Anyway if you're on Linux you can try to release memory by invoking directly the libc function malloc_trim (man page). Something like:

import ctypes
libc = ctypes.CDLL("libc.so.6")
libc.malloc_trim(0)

Java unsupported major minor version 52.0

I assumed openjdk8 would work with tomcat8 but I had to remove it and keep openjdk7 only, this fixed the issue in my case. I really don't know why or if there is something else I could have done.

Attributes / member variables in interfaces?

The point of an interface is to specify the public API. An interface has no state. Any variables that you create are really constants (so be careful about making mutable objects in interfaces).

Basically an interface says here are all of the methods that a class that implements it must support. It probably would have been better if the creators of Java had not allowed constants in interfaces, but too late to get rid of that now (and there are some cases where constants are sensible in interfaces).

Because you are just specifying what methods have to be implemented there is no idea of state (no instance variables). If you want to require that every class has a certain variable you need to use an abstract class.

Finally, you should, generally speaking, not use public variables, so the idea of putting variables into an interface is a bad idea to begin with.

Short answer - you can't do what you want because it is "wrong" in Java.

Edit:

class Tile 
    implements Rectangle 
{
    private int height;
    private int width;

     @Override
    public int getHeight() {
        return height;
    }

    @Override
    public int getWidth() {
        return width;
    }

    @Override
    public void setHeight(int h) {
        height = h;
    }

    @Override
    public void setWidth(int w) { 
        width = w;  
    }
}

an alternative version would be:

abstract class AbstractRectangle 
    implements Rectangle 
{
    private int height;
    private int width;

     @Override
    public int getHeight() {
        return height;
    }

    @Override
    public int getWidth() {
        return width;
    }

    @Override
    public void setHeight(int h) {
        height = h;
    }

    @Override
    public void setWidth(int w) { 
        width = w;  
    }
}

class Tile 
    extends AbstractRectangle 
{
}

SSL Error When installing rubygems, Unable to pull data from 'https://rubygems.org/

For windows users

Goto link http://rubygems.org/pages/download

  1. Download the latest zip file (In my case 2.4.5)
  2. Unzip it
  3. run "ruby setup.rb" in unzipped folder
  4. now run gem install command

How does the "this" keyword work?

this in JavaScript always refers to the 'owner' of the function that is being executed.

If no explicit owner is defined, then the top most owner, the window object, is referenced.

So if I did

function someKindOfFunction() {
   this.style = 'foo';
}

element.onclick = someKindOfFunction;

this would refer to the element object. But be careful, a lot of people make this mistake.

<element onclick="someKindOfFunction()">

In the latter case, you merely reference the function, not hand it over to the element. Therefore, this will refer to the window object.

Checking if an object is a given type in Swift

Just for the sake of completeness based on the accepted answer and some others:

let items : [Any] = ["Hello", "World", 1]

for obj in items where obj is String {
   // obj is a String. Do something with str
}

But you can also (compactMap also "maps" the values which filter doesn't):

items.compactMap { $0 as? String }.forEach{ /* do something with $0 */ ) }

And a version using switch:

for obj in items {
    switch (obj) {
        case is Int:
           // it's an integer
        case let stringObj as String:
           // you can do something with stringObj which is a String
        default:
           print("\(type(of: obj))") // get the type
    }
}

But sticking to the question, to check if it's an array (i.e. [String]):

let items : [Any] = ["Hello", "World", 1, ["Hello", "World", "of", "Arrays"]]

for obj in items {
  if let stringArray = obj as? [String] {
    print("\(stringArray)")
  }
}

Or more generally (see this other question answer):

for obj in items {
  if obj is [Any] {
    print("is [Any]")
  }

  if obj is [AnyObject] {
    print("is [AnyObject]")
  }

  if obj is NSArray {
    print("is NSArray")
  }
}

Creating an empty list in Python

Just to highlight @Darkonaut answer because I think it should be more visible.

new_list = [] or new_list = list() are both fine (ignoring performance), but append() returns None, as result you can't do new_list = new_list.append(something).

Send JSON data from Javascript to PHP?

PHP has a built in function called json_decode(). Just pass the JSON string into this function and it will convert it to the PHP equivalent string, array or object.

In order to pass it as a string from Javascript, you can convert it to JSON using

JSON.stringify(object);

or a library such as Prototype

How to update-alternatives to Python 3 without breaking apt?

Somehow python 3 came back (after some updates?) and is causing big issues with apt updates, so I've decided to remove python 3 completely from the alternatives:

root:~# python -V
Python 3.5.2

root:~# update-alternatives --config python
There are 2 choices for the alternative python (providing /usr/bin/python).

  Selection    Path                Priority   Status
------------------------------------------------------------
* 0            /usr/bin/python3.5   3         auto mode
  1            /usr/bin/python2.7   2         manual mode
  2            /usr/bin/python3.5   3         manual mode


root:~# update-alternatives --remove python /usr/bin/python3.5

root:~# update-alternatives --config python
There is 1 choice for the alternative python (providing /usr/bin/python).

    Selection    Path                Priority   Status
------------------------------------------------------------
  0            /usr/bin/python2.7   2         auto mode
* 1            /usr/bin/python2.7   2         manual mode

Press <enter> to keep the current choice[*], or type selection number: 0


root:~# python -V
Python 2.7.12

root:~# update-alternatives --config python
There is only one alternative in link group python (providing /usr/bin/python): /usr/bin/python2.7
Nothing to configure.

Why does JSON.parse fail with the empty string?

Because '' is not a valid Javascript/JSON object. An empty object would be '{}'

For reference: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/JSON/parse

Maximize a window programmatically and prevent the user from changing the windows state

To stop the window being resizeable once you've maximised it you need to change the FormBorderStyle from Sizable to one of the fixed constants:

FixedSingle
Fixed3D
FixedDialog

From the MSDN Page Remarks section:

The border style of the form determines how the outer edge of the form appears. In addition to changing the border display for a form, certain border styles prevent the form from being sized. For example, the FormBorderStyle.FixedDialog border style changes the border of the form to that of a dialog box and prevents the form from being resized. The border style can also affect the size or availability of the caption bar section of a form.

It will change the appearance of the form if you pick Fixed3D for example, and you'll probably have to do some work if you want the form to restore to non-maximised and be resizeable again.

Replace all spaces in a string with '+'

You need to look for some replaceAll option

str = str.replace(/ /g, "+");

this is a regular expression way of doing a replaceAll.

function ReplaceAll(Source, stringToFind, stringToReplace) {
    var temp = Source;
    var index = temp.indexOf(stringToFind);

    while (index != -1) {
        temp = temp.replace(stringToFind, stringToReplace);
        index = temp.indexOf(stringToFind);
    }

    return temp;
}

String.prototype.ReplaceAll = function (stringToFind, stringToReplace) {
    var temp = this;
    var index = temp.indexOf(stringToFind);

    while (index != -1) {
        temp = temp.replace(stringToFind, stringToReplace);
        index = temp.indexOf(stringToFind);
    }

    return temp;

};

Sorting a list with stream.sorted() in Java

Java 8 provides different utility api methods to help us sort the streams better.

If your list is a list of Integers(or Double, Long, String etc.,) then you can simply sort the list with default comparators provided by java.

List<Integer> integerList = Arrays.asList(1, 4, 3, 4, 5);

Creating comparator on fly:

integerList.stream().sorted((i1, i2) -> i1.compareTo(i2)).forEach(System.out::println);

With default comparator provided by java 8 when no argument passed to sorted():

integerList.stream().sorted().forEach(System.out::println); //Natural order

If you want to sort the same list in reverse order:

 integerList.stream().sorted(Comparator.reverseOrder()).forEach(System.out::println); // Reverse Order

If your list is a list of user defined objects, then:

List<Person> personList = Arrays.asList(new Person(1000, "First", 25, 30000),
        new Person(2000, "Second", 30, 45000),
        new Person(3000, "Third", 35, 25000));

Creating comparator on fly:

personList.stream().sorted((p1, p2) -> ((Long)p1.getPersonId()).compareTo(p2.getPersonId()))
        .forEach(person -> System.out.println(person.getName()));

Using Comparator.comparingLong() method(We have comparingDouble(), comparingInt() methods too):

personList.stream().sorted(Comparator.comparingLong(Person::getPersonId)).forEach(person -> System.out.println(person.getName()));

Using Comparator.comparing() method(Generic method which compares based on the getter method provided):

personList.stream().sorted(Comparator.comparing(Person::getPersonId)).forEach(person -> System.out.println(person.getName()));

We can do chaining too using thenComparing() method:

personList.stream().sorted(Comparator.comparing(Person::getPersonId).thenComparing(Person::getAge)).forEach(person -> System.out.println(person.getName())); //Sorting by person id and then by age.

Person class

public class Person {
    private long personId;
    private String name;
    private int age;
    private double salary;

    public long getPersonId() {
        return personId;
    }

    public void setPersonId(long personId) {
        this.personId = personId;
    }

    public Person(long personId, String name, int age, double salary) {
        this.personId = personId;
        this.name = name;
        this.age = age;

        this.salary = salary;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public double getSalary() {
        return salary;
    }

    public void setSalary(double salary) {
        this.salary = salary;
    }
}

How can I check if mysql is installed on ubuntu?

"mysql" may be found even if mysql and mariadb is uninstalled, but not "mysqld".

Faster than rpm -qa | grep mysqld is:

which mysqld

Setting onClickListener for the Drawable right of an EditText

Please use below trick:

  • Create an image button with your icon and set its background color to be transparent.
  • Put the image button on the EditText
  • Implement the 'onclic'k listener of the button to execute your function

android - setting LayoutParams programmatically

  LinearLayout.LayoutParams param = new LinearLayout.LayoutParams(
                   /*width*/ ViewGroup.LayoutParams.MATCH_PARENT,
                   /*height*/ ViewGroup.LayoutParams.MATCH_PARENT,
                   /*weight*/ 1.0f
            );
            YOUR_VIEW.setLayoutParams(param);

Programmatically Lighten or Darken a hex color (or rgb, and blend colors)

I tried your function and there was a little bug: If some final 'r' value is 1 digit only, the result comes up like: 'a0a0a' when the right value is '0a0a0a', for example. I just quick-fixed it by adding this instead of your return:

var rStr = (r.toString(16).length < 2)?'0'+r.toString(16):r.toString(16);
var gStr = (g.toString(16).length < 2)?'0'+g.toString(16):g.toString(16);
var bStr = (b.toString(16).length < 2)?'0'+b.toString(16):b.toString(16);

return (usePound?"#":"") + rStr + gStr + bStr;

Maybe it's not so nice but it do the work. Great function, BTW. Just what I needed. :)

DOM element to corresponding vue.js component

Since v-ref is no longer a directive, but a special attribute, it can also be dynamically defined. This is especially useful in combination with v-for.

For example:

<ul>
    <li v-for="(item, key) in items" v-on:click="play(item,$event)">
        <a v-bind:ref="'key' + item.id" v-bind:href="item.url">
            <!-- content -->
        </a>
    </li>
</ul>

and in Vue component you can use

var recordingModel = new Vue({
  el:'#rec-container',
  data:{
    items:[]
  },

  methods:{
    play:function(key,e){
      // it contains the bound reference
      console.log(this.$refs['item'+key]);
    }
  }
});

Cannot open solution file in Visual Studio Code

But you can open the folder with the .SLN in to edit the code in the project, which will detect the .SLN to select the library that provides Intellisense.

Get resultset from oracle stored procedure

In SQL Plus:

SQL> var r refcursor
SQL> set autoprint on
SQL> exec :r := function_returning_refcursor();

Replace the last line with a call to your procedure / function and the contents of the refcursor will be displayed

sqlalchemy IS NOT NULL select

Starting in version 0.7.9 you can use the filter operator .isnot instead of comparing constraints, like this:

query.filter(User.name.isnot(None))

This method is only necessary if pep8 is a concern.

source: sqlalchemy documentation

Python: Finding differences between elements of a list

You can use itertools.tee and zip to efficiently build the result:

from itertools import tee
# python2 only:
#from itertools import izip as zip

def differences(seq):
    iterable, copied = tee(seq)
    next(copied)
    for x, y in zip(iterable, copied):
        yield y - x

Or using itertools.islice instead:

from itertools import islice

def differences(seq):
    nexts = islice(seq, 1, None)
    for x, y in zip(seq, nexts):
        yield y - x

You can also avoid using the itertools module:

def differences(seq):
    iterable = iter(seq)
    prev = next(iterable)
    for element in iterable:
        yield element - prev
        prev = element

All these solution work in constant space if you don't need to store all the results and support infinite iterables.


Here are some micro-benchmarks of the solutions:

In [12]: L = range(10**6)

In [13]: from collections import deque
In [15]: %timeit deque(differences_tee(L), maxlen=0)
10 loops, best of 3: 122 ms per loop

In [16]: %timeit deque(differences_islice(L), maxlen=0)
10 loops, best of 3: 127 ms per loop

In [17]: %timeit deque(differences_no_it(L), maxlen=0)
10 loops, best of 3: 89.9 ms per loop

And the other proposed solutions:

In [18]: %timeit [x[1] - x[0] for x in zip(L[1:], L)]
10 loops, best of 3: 163 ms per loop

In [19]: %timeit [L[i+1]-L[i] for i in range(len(L)-1)]
1 loops, best of 3: 395 ms per loop

In [20]: import numpy as np

In [21]: %timeit np.diff(L)
1 loops, best of 3: 479 ms per loop

In [35]: %%timeit
    ...: res = []
    ...: for i in range(len(L) - 1):
    ...:     res.append(L[i+1] - L[i])
    ...: 
1 loops, best of 3: 234 ms per loop

Note that:

  • zip(L[1:], L) is equivalent to zip(L[1:], L[:-1]) since zip already terminates on the shortest input, however it avoids a whole copy of L.
  • Accessing the single elements by index is very slow because every index access is a method call in python
  • numpy.diff is slow because it has to first convert the list to a ndarray. Obviously if you start with an ndarray it will be much faster:

    In [22]: arr = np.array(L)
    
    In [23]: %timeit np.diff(arr)
    100 loops, best of 3: 3.02 ms per loop
    

Check if a Postgres JSON array contains a string

You could use @> operator to do this something like

SELECT info->>'name'
FROM rabbits
WHERE info->'food' @> '"carrots"';

Want to download a Git repository, what do I need (windows machine)?

Install mysysgit. (Same as Greg Hewgill's answer.)

Install Tortoisegit. (Tortoisegit requires mysysgit or something similiar like Cygwin.)

After TortoiseGit is installed, right-click on a folder, select Git Clone..., then enter the Url of the repository, then click Ok.

This answer is not any better than just installing mysysgit, but you can avoid the dreaded command line. :)

How to get script of SQL Server data?

I had a hell of a time finding this option in SQL Management Studio 2012, but I finally found it. The option is hiding in the Advanced button in the screen below.

I always assumed this contained just assumed advanced options for File generation, since that's what it's next to, but it turns out someone at MS is just really bad at UI design in this case. HTH somebody who comes to this thread like I did.

SQL Management Studio 2012

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException

I still remember the first weeks of my programming courses and I totally understand how you feel. Here is the code that solves your problem. In order to learn from this answer, try to run it adding several 'print' in the loop, so you can see the progress of the variables.

import java.util.*;
import java.lang.*;

public class foo
{

   public static void main(String[] args)
   { 
      double[] alpha = new double[50];
      int count = 0;

      for (int i=0; i<50; i++)
      {
          // System.out.print("variable i = " + i + "\n");
          if (i < 25)
          {
                alpha[i] = i*i;
          }
          else {
                alpha[i] = 3*i;
          }

          if (count < 10)
          {
            System.out.print(alpha[i]+ " "); 
          }  
          else {
            System.out.print("\n"); 
            System.out.print(alpha[i]+ " "); 
            count = 0;
          }

          count++;
      }

      System.out.print("\n"); 

    }
}

Exiting out of a FOR loop in a batch file?

You could simply use echo on and you will see that goto :eof or even exit /b doesn't work as expected.

The code inside of the loop isn't executed anymore, but the loop is expanded for all numbers to the end.
That's why it's so slow.

The only way to exit a FOR /L loop seems to be the variant of exit like the exsample of Wimmel, but this isn't very fast nor useful to access any results from the loop.

This shows 10 expansions, but none of them will be executed

echo on
for /l %%n in (1,1,10) do (
  goto :eof
  echo %%n
)

How to uninstall Eclipse?

Right click on eclipse icon and click on open file location then delete the eclipse folder from drive(Save backup of your eclipse workspace if you want). Also delete eclipse icon. Thats it..

How to get an Instagram Access Token

The easy way that works in 2019

Disable implicit oauth under the security auth and THEN load this:

https://api.instagram.com/oauth/authorize/?client_id=CLIENT-ID&redirect_uri=REDIRECT-URI&response_type=token

Specify REDIRECT-URI in your account and type it exactly as specified.

Top 5 time-consuming SQL queries in Oracle

I found this SQL statement to be a useful place to start (sorry I can't attribute this to the original author; I found it somewhere on the internet):

SELECT * FROM
(SELECT
    sql_fulltext,
    sql_id,
    elapsed_time,
    child_number,
    disk_reads,
    executions,
    first_load_time,
    last_load_time
FROM    v$sql
ORDER BY elapsed_time DESC)
WHERE ROWNUM < 10
/

This finds the top SQL statements that are currently stored in the SQL cache ordered by elapsed time. Statements will disappear from the cache over time, so it might be no good trying to diagnose last night's batch job when you roll into work at midday.

You can also try ordering by disk_reads and executions. Executions is useful because some poor applications send the same SQL statement way too many times. This SQL assumes you use bind variables correctly.

Then, you can take the sql_id and child_number of a statement and feed them into this baby:-

SELECT * FROM table(DBMS_XPLAN.DISPLAY_CURSOR('&sql_id', &child));

This shows the actual plan from the SQL cache and the full text of the SQL.

How to dockerize maven project? and how many ways to accomplish it?

Create a Dockerfile
#
# Build stage
#

FROM maven:3.6.3-jdk-11-slim AS build

WORKDIR usr/src/app

COPY . ./

RUN mvn clean package

#
# Package stage
#

FROM openjdk:11-jre-slim

ARG JAR_NAME="project-name"

WORKDIR /usr/src/app

EXPOSE ${HTTP_PORT}

COPY --from=build /usr/src/app/target/${JAR_NAME}.jar ./app.jar

CMD ["java","-jar", "./app.jar"]

Handling of non breaking space: <p>&nbsp;</p> vs. <p> </p>

In HTML, elements containing nothing but normal whitespace characters are considered empty. A paragraph that contains just a normal space character will have zero height. A non-breaking space is a special kind of whitespace character that isn't considered to be insignificant, so it can be used as content for a non-empty paragraph.

Even if you consider CSS margins on paragraphs, since an "empty" paragraph has zero height, its vertical margins will collapse. This causes it to have no height and no margins, making it appear as if it were never there at all.

How to use type: "POST" in jsonp ajax call

Use json in dataType and send like this:

    $.ajax({
        url: "your url which return json",
        type: "POST",
        crossDomain: true,
        data: data,
        dataType: "json",
        success:function(result){
            alert(JSON.stringify(result));
        },
        error:function(xhr,status,error){
            alert(status);
        }
    });

and put this lines in your server side file:

if PHP:

header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST');
header('Access-Control-Max-Age: 1000');

if java:

response.addHeader( "Access-Control-Allow-Origin", "*" ); 
response.addHeader( "Access-Control-Allow-Methods", "POST" ); 
response.addHeader( "Access-Control-Max-Age", "1000" );

Convert from MySQL datetime to another format with PHP

SELECT 
 DATE_FORMAT(demo.dateFrom, '%e.%M.%Y') as dateFrom,
 DATE_FORMAT(demo.dateUntil, '%e.%M.%Y') as dateUntil
FROM demo

If you dont want to change every function in your PHP code, to show the expected date format, change it at the source - your database.

It is important to name the rows with the as operator as in the example above (as dateFrom, as dateUntil). The names you write there are the names, the rows will be called in your result.

The output of this example will be

[Day of the month, numeric (0..31)].[Month name (January..December)].[Year, numeric, four digits]

Example: 5.August.2015

Change the dots with the separator of choice and check the DATE_FORMAT(date,format) function for more date formats.

Sum up a column from a specific row down

Something like this worked for me (references columns C and D from the row 8 till the end of the columns, in Excel 2013 if relevant):

=SUMIFS(INDIRECT(ADDRESS(ROW(D$8), COLUMN())&":"&ADDRESS(ROWS($C:$C), COLUMN())),INDIRECT("C$8:C"&ROWS($C:$C)),$C$2)

how do I strip white space when grabbing text with jQuery?

Use the replace function in js:

var emailAdd = $(this).text().replace(/ /g,'');

That will remove all the spaces

If you want to remove the leading and trailing whitespace only, use the jQuery $.trim method :

var emailAdd = $.trim($(this).text());

How do I install Java on Mac OSX allowing version switching?

Note: These solutions work for various versions of Java including Java 8, Java 11, and the new Java 15, and for any other previous Java version covered by the listed version managers. This includes alternative JDK's from OpenJDK, Oracle, IBM, Azul, Amazon Correto, Graal and more. Easily work with Java 7, Java 8, Java 9, Java 10, Java 11, Java 12, Java 13, Java 14, and Java 15!

You have a few options for how to do the installation as well as manage JDK switching. Installation can be done by Homebrew, SDKMAN, Jabba, or a manual install. Switching can be done by JEnv, SDKMAN, Jabba, or manually by setting JAVA_HOME. All of these are described below.


Installation

First, install Java using whatever method you prefer including Homebrew, SDKMAN or a manual install of the tar.gz file. The advantage of a manual install is that the location of the JDK can be placed in a standardized location for Mac OSX. Otherwise, there are easier options such as SDKMAN that also will install other important and common tools for the JVM.

Installing and Switching versions with SDKMAN

SDKMAN is a bit different and handles both the install and the switching. SDKMAN also places the installed JDK's into its own directory tree, which is typically ~/.sdkman/candidates/java. SDKMAN allows setting a global default version, and a version specific to the current shell.

  1. Install SDKMAN from https://sdkman.io/install

  2. List the Java versions available to make sure you know the version ID

    sdk list java
    
  3. Install one of those versions, for example, Java 15:

    sdk install java 15-open 
    
  4. Make 15 the default version:

    sdk default java 15-open
    

    Or switch to 15 for the session:

    sdk use java 15-open
    

When you list available versions for installation using the list command, you will see a wide variety of distributions of Java:

sdk list java

And install additional versions, such as JDK 8:

sdk install java 8.0.181-oracle

SDKMAN can work with previously installed existing versions. Just do a local install giving your own version label and the location of the JDK:

sdk install java my-local-13 /Library/Java/JavaVirtualMachines/jdk-13.jdk/Contents/Home

And use it freely:

sdk use java my-local-13

More information is available in the SDKMAN Usage Guide along with other SDK's it can install and manage.

SDKMAN will automatically manage your PATH and JAVA_HOME for you as you change versions.


Install manually from OpenJDK download page:

  1. Download OpenJDK for Mac OSX from http://jdk.java.net/ (for example Java 15)

  2. Unarchive the OpenJDK tar, and place the resulting folder (i.e. jdk-15.jdk) into your /Library/Java/JavaVirtualMachines/ folder since this is the standard and expected location of JDK installs. You can also install anywhere you want in reality.

Install with Homebrew

The version of Java available in Homebrew Cask previous to October 3, 2018 was indeed the Oracle JVM. Now, however, it has now been updated to OpenJDK. Be sure to update Homebrew and then you will see the lastest version available for install.

  1. install Homebrew if you haven't already. Make sure it is updated:

     brew update
    
  2. Add the casks tap, if you want to use the AdoptOpenJDK versions (which tend to be more current):

     brew tap adoptopenjdk/openjdk
    

    These casks change their Java versions often, and there might be other taps out there with additional Java versions.

  3. Look for installable versions:

     brew search java   
    

    or for AdoptOpenJDK versions:

     brew search jdk     
    
  4. Check the details on the version that will be installed:

     brew info java
    

    or for the AdoptOpenJDK version:

     brew info adoptopenjdk
    
  5. Install a specific version of the JDK such as java11, adoptopenjdk8, or adoptopenjdk13, or just java or adoptopenjdk for the most current of that distribution. For example:

     brew install java
    
     brew cask install adoptopenjdk13
    

And these will be installed into /Library/Java/JavaVirtualMachines/ which is the traditional location expected on Mac OSX.

Other installation options:

Some other flavours of OpenJDK are:

Azul Systems Java Zulu certified builds of OpenJDK can be installed by following the instructions on their site.

Zulu® is a certified build of OpenJDK that is fully compliant with the Java SE standard. Zulu is 100% open source and freely downloadable. Now Java developers, system administrators, and end-users can enjoy the full benefits of open source Java with deployment flexibility and control over upgrade timing.

Amazon Correto OpenJDK builds have an easy to use an installation package for Java 8 or Java 11, and installs to the standard /Library/Java/JavaVirtualMachines/ directory on Mac OSX.

Amazon Corretto is a no-cost, multiplatform, production-ready distribution of the Open Java Development Kit (OpenJDK). Corretto comes with long-term support that will include performance enhancements and security fixes. Amazon runs Corretto internally on thousands of production services and Corretto is certified as compatible with the Java SE standard. With Corretto, you can develop and run Java applications on popular operating systems, including Linux, Windows, and macOS.


Where is my JDK?!?!

To find locations of previously installed Java JDK's installed at the default system locations, use:

/usr/libexec/java_home -V

Matching Java Virtual Machines (8):
15, x86_64: "OpenJDK 15" /Library/Java/JavaVirtualMachines/jdk-15.jdk/Contents/Home 14, x86_64: "OpenJDK 14" /Library/Java/JavaVirtualMachines/jdk-14.jdk/Contents/Home 13, x86_64: "OpenJDK 13" /Library/Java/JavaVirtualMachines/openjdk-13.jdk/Contents/Home 12, x86_64: "OpenJDK 12" /Library/Java/JavaVirtualMachines/jdk-12.jdk/Contents/Home
11, x86_64: "Java SE 11" /Library/Java/JavaVirtualMachines/jdk-11.jdk/Contents/Home
10.0.2, x86_64: "Java SE 10.0.2" /Library/Java/JavaVirtualMachines/jdk-10.0.2.jdk/Contents/Home
9, x86_64: "Java SE 9" /Library/Java/JavaVirtualMachines/jdk-9.jdk/Contents/Home
1.8.0_144, x86_64: "Java SE 8" /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home

You can also report just the location of a specific Java version using -v. For example for Java 15:

/usr/libexec/java_home -v 15

/Library/Java/JavaVirtualMachines/jdk-15.jdk/Contents/Home

Knowing the location of the installed JDK's is also useful when using tools like JEnv, or adding a local install to SDKMAN, or linking a system JDK in Jabba -- and you need to know where to find them.

If you need to find JDK's installed by other tools, check these locations:

  • SDKMAN installs to ~/.sdkman/candidates/java/
  • Jabba installs to ~/.jabba/jdk

Switching versions manually

The Java executable is a wrapper that will use whatever JDK is configured in JAVA_HOME, so you can change that to also change which JDK is in use.

For example, if you installed or untar'd JDK 15 to /Library/Java/JavaVirtualMachines/jdk-15.jdk if it is the highest version number it should already be the default, if not you could simply set:

export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk-15.jdk/Contents/Home

And now whatever Java executable is in the path will see this and use the correct JDK.

Using the /usr/libexec/java_home utility as previously described helps you to create aliases or to run commands to change Java versions by identifying the locations of different JDK installations. For example, creating shell aliases in your .profile or .bash_profile to change JAVA_HOME for you:

export JAVA_8_HOME=$(/usr/libexec/java_home -v1.8)
export JAVA_9_HOME=$(/usr/libexec/java_home -v9)
export JAVA_10_HOME=$(/usr/libexec/java_home -v10)
export JAVA_11_HOME=$(/usr/libexec/java_home -v11)
export JAVA_12_HOME=$(/usr/libexec/java_home -v12)
export JAVA_13_HOME=$(/usr/libexec/java_home -v13)
export JAVA_14_HOME=$(/usr/libexec/java_home -v14)
export JAVA_15_HOME=$(/usr/libexec/java_home -v15)

alias java8='export JAVA_HOME=$JAVA_8_HOME'
alias java9='export JAVA_HOME=$JAVA_9_HOME'
alias java10='export JAVA_HOME=$JAVA_10_HOME'
alias java11='export JAVA_HOME=$JAVA_11_HOME'
alias java12='export JAVA_HOME=$JAVA_12_HOME'
alias java13='export JAVA_HOME=$JAVA_13_HOME'
alias java14='export JAVA_HOME=$JAVA_14_HOME'
alias java15='export JAVA_HOME=$JAVA_15_HOME'

# default to Java 15
java15

Then to change versions, just use the alias.

java8
java -version

java version "1.8.0_144"

Of course, setting JAVA_HOME manually works too!


Switching versions with JEnv

JEnv expects the Java JDK's to already exist on the machine and can be in any location. Typically you will find installed Java JDK's in /Library/Java/JavaVirtualMachines/. JEnv allows setting the global version of Java, one for the current shell, and a per-directory local version which is handy when some projects require different versions than others.

  1. Install JEnv if you haven't already, instructions on the site http://www.jenv.be/ for manual install or using Homebrew.

  2. Add any Java version to JEnv (adjust the directory if you placed this elsewhere):

    jenv add /Library/Java/JavaVirtualMachines/jdk-15.jdk/Contents/Home
    
  3. Set your global version using this command:

    jenv global 15
    

You can also add other existing versions using jenv add in a similar manner, and list those that are available. For example Java 8:

jenv add /Library/Java/JavaVirtualMachines/jdk1.8.0_144.jdk/Contents/Home 
jenv versions

See the JEnv docs for more commands. You may now switch between any Java versions (Oracle, OpenJDK, other) at any time either for the whole system, for shells, or per local directory.

To help manage JAVA_HOME while using JEnv you can add the export plugin to do this for you.

$ jenv enable-plugin export
  You may restart your session to activate jenv export plugin echo export plugin activated

The export plugin may not adjust JAVA_HOME if it is already set, so you may need to clear this variable in your profile so that it can be managed by JEnv.

You can also use jenv exec <command> <parms...> to run single commands with JAVA_HOME and PATH set correctly for that one command, which could include opening another shell.


Installing and Switching versions with Jabba

Jabba also handles both the install and the switching. Jabba also places the installed JDK's into its own directory tree, which is typically ~/.jabba/jdk.

  1. Install Jabba by following the instructions on the home page.

  2. List available JDK's

    jabba ls-remote

  3. Install Java JDK 12

    jabba install [email protected]

  4. Use it:

    jabba use [email protected]

You can also alias version names, link to existing JDK's already installed, and find a mix of interesting JDK's such as GraalVM, Adopt JDK, IBM JDK, and more. The complete usage guide is available on the home page as well.

Jabba will automatically manage your PATH and JAVA_HOME for you as you change versions.

How to edit/save a file through Ubuntu Terminal

Within Nano use Ctrl+O to save and Ctrl+X to exit if you were wondering

Go to "next" iteration in JavaScript forEach loop

You can simply return if you want to skip the current iteration.

Since you're in a function, if you return before doing anything else, then you have effectively skipped execution of the code below the return statement.

Regex using javascript to return just numbers

You could also strip all the non-digit characters (\D or [^0-9]):

_x000D_
_x000D_
let word_With_Numbers = 'abc123c def4567hij89'_x000D_
let word_Without_Numbers = word_With_Numbers.replace(/\D/g, '');_x000D_
_x000D_
console.log(word_Without_Numbers)
_x000D_
_x000D_
_x000D_

Get yesterday's date in bash on Linux, DST-safe

This should also work, but perhaps it is too much:

date -d @$(( $(date +"%s") - 86400)) +"%Y-%m-%d"

How do I print the full value of a long string in gdb?

set print elements 0

From the GDB manual:

set print elements number-of-elements
Set a limit on how many elements of an array GDB will print. If GDB is printing a large array, it stops printing after it has printed the number of elements set by the set print elements command. This limit also applies to the display of strings. When GDB starts, this limit is set to 200. Setting number-of-elements to zero means that the printing is unlimited.

Convert string to integer type in Go?

For example,

package main

import (
    "flag"
    "fmt"
    "os"
    "strconv"
)

func main() {
    flag.Parse()
    s := flag.Arg(0)
    // string to int
    i, err := strconv.Atoi(s)
    if err != nil {
        // handle error
        fmt.Println(err)
        os.Exit(2)
    }
    fmt.Println(s, i)
}

Navigation drawer: How do I set the selected item at startup?

You can both highlight and select the item with the following 1-liner:

navigationView.getMenu().performIdentifierAction(R.id.posts, 0);

Source: https://stackoverflow.com/a/31044917/383761

How to convert an Stream into a byte[] in C#?

The shortest solution I know:

using(var memoryStream = new MemoryStream())
{
  sourceStream.CopyTo(memoryStream);
  return memoryStream.ToArray();
}

Searching a list of objects in Python

Simple, Elegant, and Powerful:

A generator expression in conjuction with a builtin… (python 2.5+)

any(x for x in mylist if x.n == 10)

Uses the Python any() builtin, which is defined as follows:

any(iterable) -> Return True if any element of the iterable is true. Equivalent to:

def any(iterable):
    for element in iterable:
        if element:
            return True
    return False

Plotting a fast Fourier transform in Python

There are already great solutions on this page, but all have assumed the dataset is uniformly/evenly sampled/distributed. I will try to provide a more general example of randomly sampled data. I will also use this MATLAB tutorial as an example:

Adding the required modules:

import numpy as np
import matplotlib.pyplot as plt
import scipy.fftpack
import scipy.signal

Generating sample data:

N = 600 # Number of samples
t = np.random.uniform(0.0, 1.0, N) # Assuming the time start is 0.0 and time end is 1.0
S = 1.0 * np.sin(50.0 * 2 * np.pi * t) + 0.5 * np.sin(80.0 * 2 * np.pi * t)
X = S + 0.01 * np.random.randn(N) # Adding noise

Sorting the data set:

order = np.argsort(t)
ts = np.array(t)[order]
Xs = np.array(X)[order]

Resampling:

T = (t.max() - t.min()) / N # Average period
Fs = 1 / T # Average sample rate frequency
f = Fs * np.arange(0, N // 2 + 1) / N; # Resampled frequency vector
X_new, t_new = scipy.signal.resample(Xs, N, ts)

Plotting the data and resampled data:

plt.xlim(0, 0.1)
plt.plot(t_new, X_new, label="resampled")
plt.plot(ts, Xs, label="org")
plt.legend()
plt.ylabel("X")
plt.xlabel("t")

Enter image description here

Now calculating the FFT:

Y = scipy.fftpack.fft(X_new)
P2 = np.abs(Y / N)
P1 = P2[0 : N // 2 + 1]
P1[1 : -2] = 2 * P1[1 : -2]

plt.ylabel("Y")
plt.xlabel("f")
plt.plot(f, P1)

Enter image description here

P.S. I finally got time to implement a more canonical algorithm to get a Fourier transform of unevenly distributed data. You may see the code, description, and example Jupyter notebook here.

Access PHP variable in JavaScript

I'm not sure how necessary this is, and it adds a call to getElementById, but if you're really keen on getting inline JavaScript out of your code, you can pass it as an HTML attribute, namely:

<span class="metadata" id="metadata-size-of-widget" title="<?php echo json_encode($size_of_widget) ?>"></span>

And then in your JavaScript:

var size_of_widget = document.getElementById("metadata-size-of-widget").title;

How can I shutdown Spring task executor/scheduler pools before all other beans in the web app are destroyed?

Two ways:

  1. Have a bean implement ApplicationListener<ContextClosedEvent>. onApplicationEvent() will get called before the context and all the beans are destroyed.

  2. Have a bean implement Lifecycle or SmartLifecycle. stop() will get called before the context and all the beans are destroyed.

Either way you can shut down the task stuff before the bean destroying mechanism takes place.

Eg:

@Component
public class ContextClosedHandler implements ApplicationListener<ContextClosedEvent> {
    @Autowired ThreadPoolTaskExecutor executor;
    @Autowired ThreadPoolTaskScheduler scheduler;

    @Override
    public void onApplicationEvent(ContextClosedEvent event) {
        scheduler.shutdown();
        executor.shutdown();
    }       
}

(Edit: Fixed method signature)

When adding a Javascript library, Chrome complains about a missing source map, why?

This is what worked for me: instead of

<script src="https://cdn.jsdelivr.net/npm/@tensorflow/tfjs"></script>

try

<script src="https://cdn.jsdelivr.net/npm/@tensorflow/tfjs/dist/tf.min.js"> </script>

After that change I am not seeing the error anymore.

Django - what is the difference between render(), render_to_response() and direct_to_template()?

Render is

def render(request, *args, **kwargs):
    """ Simple wrapper for render_to_response. """
    kwargs['context_instance'] = RequestContext(request)
    return render_to_response(*args, **kwargs)

So there is really no difference between render_to_response except it wraps your context making the template pre-processors work.

Direct to template is a generic view.

There is really no sense in using it here because there is overhead over render_to_response in the form of view function.

How does jQuery work when there are multiple elements with the same ID value?

If you have multiple elements with same id or same name, just assign same class to those multiple elements and access them by index & perform your required operation.

  <div>
        <span id="a" class="demo">1</span>
        <span id="a" class="demo">2</span>
        <span>3</span>
    </div>

JQ:

$($(".demo")[0]).val("First span");
$($(".demo")[1]).val("Second span");

Setting the Vim background colors

As vim's own help on set background says, "Setting this option does not change the background color, it tells Vim what the background color looks like. For changing the background color, see |:hi-normal|."

For example

:highlight Normal ctermfg=grey ctermbg=darkblue

will write in white on blue on your color terminal.

How to "scan" a website (or page) for info, and bring it into my program?

You could also try jARVEST.

It is based on a JRuby DSL over a pure-Java engine to spider-scrape-transform web sites.

Example:

Find all links inside a web page (wget and xpath are constructs of the jARVEST's language):

wget | xpath('//a/@href')

Inside a Java program:

Jarvest jarvest = new Jarvest();
  String[] results = jarvest.exec(
    "wget | xpath('//a/@href')", //robot! 
    "http://www.google.com" //inputs
  );
  for (String s : results){
    System.out.println(s);
  }

how to extract only the year from the date in sql server 2008?

You can use year() function in sql to get the year from the specified date.

Syntax:

YEAR ( date )

For more information check here

base 64 encode and decode a string in angular (2+)

For encoding to base64 in Angular2, you can use btoa() function.

Example:-

console.log(btoa("stringAngular2")); 
// Output:- c3RyaW5nQW5ndWxhcjI=

For decoding from base64 in Angular2, you can use atob() function.

Example:-

console.log(atob("c3RyaW5nQW5ndWxhcjI=")); 
// Output:- stringAngular2

Finding out the name of the original repository you cloned from in Git

I stumbled on this question trying to get the organization/repo string from a git host like github or gitlab.

This is working for me:

git config --get remote.origin.url | sed -e 's/^git@.*:\([[:graph:]]*\).git/\1/'

It uses sed to replace the output of the git config command with just the organization and repo name.

Something like github/scientist would be matched by the character class [[:graph:]] in the regular expression.

The \1 tells sed to replace everything with just the matched characters.

Changing plot scale by a factor in matplotlib

As you have noticed, xscale and yscale does not support a simple linear re-scaling (unfortunately). As an alternative to Hooked's answer, instead of messing with the data, you can trick the labels like so:

ticks = ticker.FuncFormatter(lambda x, pos: '{0:g}'.format(x*scale))
ax.xaxis.set_major_formatter(ticks)

A complete example showing both x and y scaling:

import numpy as np
import pylab as plt
import matplotlib.ticker as ticker

# Generate data
x = np.linspace(0, 1e-9)
y = 1e3*np.sin(2*np.pi*x/1e-9) # one period, 1k amplitude

# setup figures
fig = plt.figure()
ax1 = fig.add_subplot(121)
ax2 = fig.add_subplot(122)
# plot two identical plots
ax1.plot(x, y)
ax2.plot(x, y)

# Change only ax2
scale_x = 1e-9
scale_y = 1e3
ticks_x = ticker.FuncFormatter(lambda x, pos: '{0:g}'.format(x/scale_x))
ax2.xaxis.set_major_formatter(ticks_x)

ticks_y = ticker.FuncFormatter(lambda x, pos: '{0:g}'.format(x/scale_y))
ax2.yaxis.set_major_formatter(ticks_y)

ax1.set_xlabel("meters")
ax1.set_ylabel('volt')
ax2.set_xlabel("nanometers")
ax2.set_ylabel('kilovolt')

plt.show() 

And finally I have the credits for a picture:

Left: ax1 no scaling, right: ax2 y axis scaled to kilo and x axis scaled to nano

Note that, if you have text.usetex: true as I have, you may want to enclose the labels in $, like so: '${0:g}$'.

Best Practices: working with long, multiline strings in PHP?

I use templates for long text:

email-template.txt contains

hello {name}!
how are you? 

In PHP I do this:

$email = file_get_contents('email-template.txt');
$email = str_replace('{name},', 'Simon', $email);

How do I UPDATE from a SELECT in SQL Server?

Consolidating all the different approaches here.

  1. Select update
  2. Update with a common table expression
  3. Merge

Sample table structure is below and will update from Product_BAK to Product table.

Product

CREATE TABLE [dbo].[Product](
    [Id] [int] IDENTITY(1, 1) NOT NULL,
    [Name] [nvarchar](100) NOT NULL,
    [Description] [nvarchar](100) NULL
) ON [PRIMARY]

Product_BAK

    CREATE TABLE [dbo].[Product_BAK](
        [Id] [int] IDENTITY(1, 1) NOT NULL,
        [Name] [nvarchar](100) NOT NULL,
        [Description] [nvarchar](100) NULL
    ) ON [PRIMARY]

1. Select update

    update P1
    set Name = P2.Name
    from Product P1
    inner join Product_Bak P2 on p1.id = P2.id
    where p1.id = 2

2. Update with a common table expression

    ; With CTE as
    (
        select id, name from Product_Bak where id = 2
    )
    update P
    set Name = P2.name
    from  product P  inner join CTE P2 on P.id = P2.id
    where P2.id = 2

3. Merge

    Merge into product P1
    using Product_Bak P2 on P1.id = P2.id

    when matched then
    update set p1.[description] = p2.[description], p1.name = P2.Name;

In this Merge statement, we can do inset if not finding a matching record in the target, but exist in the source and please find syntax:

    Merge into product P1
    using Product_Bak P2 on P1.id = P2.id;

    when matched then
    update set p1.[description] = p2.[description], p1.name = P2.Name;

    WHEN NOT MATCHED THEN
    insert (name, description)
    values(p2.name, P2.description);