#Portable applications | Programs & Examples on Portable applications

What's wrong with foreign keys?

Additional Reason to use Foreign Keys: - Allows greater reuse of a database

Additional Reason to NOT use Foreign Keys: - You are trying to lock-in a customer into your tool by reducing reuse.

div inside table

It is allow as TD can contain inline- AND block-elements.

Here you can find it in the reference: http://xhtml.com/en/xhtml/reference/td/#td-contains

How do I save JSON to local text file

Here is a solution on pure js. You can do it with html5 saveAs. For example this lib could be helpful: https://github.com/eligrey/FileSaver.js
Look at the demo: http://eligrey.com/demos/FileSaver.js/
P.S. There is no information about json save, but you can do it changing file type to "application/json" and format to .json

Removing object properties with Lodash

You can easily do this using _.pick:

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var model = {
  fname: null,
  lname: null
};

var credentials = {
  fname: 'abc',
  lname: 'xyz',
  age: 2
};

var result = _.pick(credentials, _.keys(model));


console.log('result =', result);

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<script src="https://cdn.jsdelivr.net/lodash/4.16.4/lodash.min.js"></script>

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But you can simply use pure JavaScript (specially if you use ECMAScript 6), like this:

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const model = {
  fname: null,
  lname: null
};

const credentials = {
  fname: 'abc',
  lname: 'xyz',
  age: 2
};

const newModel = {};

Object.keys(model).forEach(key => newModel[key] = credentials[key]);

console.log('newModel =', newModel);

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Querying a linked sql server

try Select * from openquery("aa-db-dev01",'Select * from users') ,the database connection should be defined in he linked server configuration

Python subprocess.Popen "OSError: [Errno 12] Cannot allocate memory"

Have you tried using:

(status,output) = commands.getstatusoutput("ps aux")

I thought this had fixed the exact same problem for me. But then my process ended up getting killed instead of failing to spawn, which is even worse..

After some testing I found that this only occurred on older versions of python: it happens with 2.6.5 but not with 2.7.2

My search had led me here python-close_fds-issue, but unsetting closed_fds had not solved the issue. It is still well worth a read.

I found that python was leaking file descriptors by just keeping an eye on it:

watch "ls /proc/$PYTHONPID/fd | wc -l"

Like you, I do want to capture the command's output, and I do want to avoid OOM errors... but it looks like the only way is for people to use a less buggy version of Python. Not ideal...

How to play YouTube video in my Android application?

I didn't want to have to have the YouTube app present on the device so I used this tutorial:

http://www.viralandroid.com/2015/09/how-to-embed-youtube-video-in-android-webview.html

...to produce this code in my app:

WebView mWebView; 

@Override
public void onCreate(Bundle savedInstanceState) {
    setContentView(R.layout.video_webview);
    mWebView=(WebView)findViewById(R.id.videoview);

    //build your own src link with your video ID
    String videoStr = "<html><body>Promo video<br><iframe width=\"420\" height=\"315\" src=\"https://www.youtube.com/embed/47yJ2XCRLZs\" frameborder=\"0\" allowfullscreen></iframe></body></html>";

    mWebView.setWebViewClient(new WebViewClient() {
        @Override
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
                return false;
        }
    });
    WebSettings ws = mWebView.getSettings();
    ws.setJavaScriptEnabled(true);
    mWebView.loadData(videoStr, "text/html", "utf-8");

}

//video_webview
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_marginLeft="0dp"
    android:layout_marginRight="0dp"
    android:background="#000000"
    android:id="@+id/bmp_programme_ll"
    android:orientation="vertical" >

   <WebView
    android:id="@+id/videoview" 
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    />  
</LinearLayout>

This worked just how I wanted it. It doesn't autoplay but the video streams within my app. Worth noting that some restricted videos won't play when embedded.

Can a table have two foreign keys?

create table Table1
(
  id varchar(2),
  name varchar(2),
  PRIMARY KEY (id)
)


Create table Table1_Addr
(
  addid varchar(2),
  Address varchar(2),
  PRIMARY KEY (addid)
)

Create table Table1_sal
(
  salid varchar(2),`enter code here`
  addid varchar(2),
  id varchar(2),
  PRIMARY KEY (salid),
  index(addid),
  index(id),
  FOREIGN KEY (addid) REFERENCES Table1_Addr(addid),
  FOREIGN KEY (id) REFERENCES Table1(id)
)

How can one see content of stack with GDB?

Use:

bt - backtrace: show stack functions and args
info frame - show stack start/end/args/locals pointers
x/100x $sp - show stack memory

(gdb) bt
#0  zzz () at zzz.c:96
#1  0xf7d39cba in yyy (arg=arg@entry=0x0) at yyy.c:542
#2  0xf7d3a4f6 in yyyinit () at yyy.c:590
#3  0x0804ac0c in gnninit () at gnn.c:374
#4  main (argc=1, argv=0xffffd5e4) at gnn.c:389

(gdb) info frame
Stack level 0, frame at 0xffeac770:
 eip = 0x8049047 in main (goo.c:291); saved eip 0xf7f1fea1
 source language c.
 Arglist at 0xffeac768, args: argc=1, argv=0xffffd5e4
 Locals at 0xffeac768, Previous frame's sp is 0xffeac770
 Saved registers:
  ebx at 0xffeac75c, ebp at 0xffeac768, esi at 0xffeac760, edi at 0xffeac764, eip at 0xffeac76c

(gdb) x/10x $sp
0xffeac63c: 0xf7d39cba  0xf7d3c0d8  0xf7d3c21b  0x00000001
0xffeac64c: 0xf78d133f  0xffeac6f4  0xf7a14450  0xffeac678
0xffeac65c: 0x00000000  0xf7d3790e

Declaring abstract method in TypeScript

If you take Erics answer a little further you can actually create a pretty decent implementation of abstract classes, with full support for polymorphism and the ability to call implemented methods from the base class. Let's start with the code:

/**
 * The interface defines all abstract methods and extends the concrete base class
 */
interface IAnimal extends Animal {
    speak() : void;
}

/**
 * The abstract base class only defines concrete methods & properties.
 */
class Animal {

    private _impl : IAnimal;

    public name : string;

    /**
     * Here comes the clever part: by letting the constructor take an 
     * implementation of IAnimal as argument Animal cannot be instantiated
     * without a valid implementation of the abstract methods.
     */
    constructor(impl : IAnimal, name : string) {
        this.name = name;
        this._impl = impl;

        // The `impl` object can be used to delegate functionality to the
        // implementation class.
        console.log(this.name + " is born!");
        this._impl.speak();
    }
}

class Dog extends Animal implements IAnimal {
    constructor(name : string) {
        // The child class simply passes itself to Animal
        super(this, name);
    }

    public speak() {
        console.log("bark");
    }
}

var dog = new Dog("Bob");
dog.speak(); //logs "bark"
console.log(dog instanceof Dog); //true
console.log(dog instanceof Animal); //true
console.log(dog.name); //"Bob"

Since the Animal class requires an implementation of IAnimal it's impossible to construct an object of type Animal without having a valid implementation of the abstract methods. Note that for polymorphism to work you need to pass around instances of IAnimal, not Animal. E.g.:

//This works
function letTheIAnimalSpeak(animal: IAnimal) {
    console.log(animal.name + " says:");
    animal.speak();
}
//This doesn't ("The property 'speak' does not exist on value of type 'Animal')
function letTheAnimalSpeak(animal: Animal) {
    console.log(animal.name + " says:");
    animal.speak();
}

The main difference here with Erics answer is that the "abstract" base class requires an implementation of the interface, and thus cannot be instantiated on it's own.

How to set conditional breakpoints in Visual Studio?

Set a breakpoint as usual.
Right-click on the breakpoint marker
Click "Condition..."
Write a condition, you may use variable names
Select either "Is True" or "Has Changed"

How comment a JSP expression?

Pure JSP comments look like this:

<%-- Comment --%>

So if you want to retain the "=".you could do something like:

<%--= map.size() --%>

The key thing is that <%= defines the beginning of an expression, in which you can't leave the body empty, but you could do something like this instead if the pure JSP comment doesn't appeal to you:

<% /*= map.size()*/ %>

Code Conventions for the JavaServer Pages Technology Version 1.x Language has details about the different commenting options available to you (but has a complete lack of link targets, so I can't link you directly to the relevant section - boo!)

jQuery text() and newlines

I would suggest to work with the someElem element directly, as replacements with .html() would replace other HTML tags within the string as well.

Here is my function:

function nl2br(el) {
  var lines = $(el).text().split(/\n/);
  $(el).empty();
  for (var i = 0 ; i < lines.length ; i++) {
    if (i > 0) $(el).append('<br>');
    $(el).append(document.createTextNode(lines[i]));
  }
  return el;
}

Call it by:

someElem = nl2br(someElem);

php foreach with multidimensional array

This would have been a comment under Brad's answer, but I don't have a high enough reputation.

Recently I found that I needed the key of the multidimensional array too, i.e., it wasn't just an index for the array, in the foreach loop.

In order to achieve that, you could use something very similar to the accepted answer, but instead split the key and value as follows

foreach ($mda as $mdaKey => $mdaData) {
    echo $mdaKey . ": " . $mdaData["value"];
}

Hope that helps someone.

Checking if a folder exists (and creating folders) in Qt, C++

To check if a directory named "Folder" exists use:

QDir("Folder").exists();

To create a new folder named "MyFolder" use:

QDir().mkdir("MyFolder");

MySQL dump by query

not mysqldump, but mysql cli...

mysql -e "select * from myTable" -u myuser -pxxxxxxxxx mydatabase

you can redirect it out to a file if you want :

mysql -e "select * from myTable" -u myuser -pxxxxxxxx mydatabase > mydumpfile.txt

Update: Original post asked if he could dump from the database by query. What he asked and what he meant were different. He really wanted to just mysqldump all tables.

mysqldump --tables myTable --where="id < 1000"

What's a good hex editor/viewer for the Mac?

One recommendation I've gotten is Hex Fiend.

Why, Fatal error: Class 'PHPUnit_Framework_TestCase' not found in ...?

For me, it was because I ran

$ phpunit .

instead of

$ phpunit

when I already had a configured phpunit.xml file in the working directory.

How do I write a correct micro-benchmark in Java?

If you are trying to compare two algorithms, do at least two benchmarks for each, alternating the order. i.e.:

for(i=1..n)
  alg1();
for(i=1..n)
  alg2();
for(i=1..n)
  alg2();
for(i=1..n)
  alg1();

I have found some noticeable differences (5-10% sometimes) in the runtime of the same algorithm in different passes..

Also, make sure that n is very large, so that the runtime of each loop is at the very least 10 seconds or so. The more iterations, the more significant figures in your benchmark time and the more reliable that data is.

How can I extract all values from a dictionary in Python?

Use values()

>>> d = {1:-0.3246, 2:-0.9185, 3:-3985}

>>> d.values()
<<< [-0.3246, -0.9185, -3985]

error MSB6006: "cmd.exe" exited with code 1

I also faced similar issue.

My source path had one directory with 'space' (D:/source 2012). I resolved this by removing the space (D:/source2012).

Finding the source code for built-in Python functions?

Here is a cookbook answer to supplement @Chris' answer, CPython has moved to GitHub and the Mercurial repository will no longer be updated:

Install Git if necessary.
git clone https://github.com/python/cpython.git
Code will checkout to a subdirectory called cpython -> cd cpython
Let's say we are looking for the definition of print()...
egrep --color=always -R 'print' | less -R
Aha! See Python/bltinmodule.c -> builtin_print()

Enjoy.

getString Outside of a Context or Activity

BTW, one of the reason of symbol not found error may be that your IDE imported android.R; class instead of yours one. Just change import android.R; to import your.namespace.R;

So 2 basic things to get string visible in the different class:

//make sure you are importing the right R class
import your.namespace.R;

//don't forget about the context
public void some_method(Context context) {
   context.getString(R.string.YOUR_STRING);
}

Convert datetime to valid JavaScript date

You can use moment.js for that, it will convert DateTime object into valid Javascript formated date:

   moment(DateOfBirth).format('DD-MMM-YYYY'); // put format as you want 

   Output: 28-Apr-1993

Hope it will help you :)

Get the element with the highest occurrence in an array

Another JS solution from: https://www.w3resource.com/javascript-exercises/javascript-array-exercise-8.php

Can try this too:

let arr =['pear', 'apple', 'orange', 'apple'];

function findMostFrequent(arr) {
  let mf = 1;
  let m = 0;
  let item;

  for (let i = 0; i < arr.length; i++) {
    for (let j = i; j < arr.length; j++) {
      if (arr[i] == arr[j]) {
        m++;
        if (m > mf) {
          mf = m;
          item = arr[i];
        }
      }
    }
    m = 0;
  }

  return item;
}

findMostFrequent(arr); // apple

How to remove a Gitlab project?

As of September 2017,
1. Click on your project.
2. Select setting on the top most corner.
3. Scroll down the page and click on expand in front of advance setting.
4. Scroll down the page and click on the Remove Project button.
5. Type your project name in text box and click on confirm.

How to start jenkins on different port rather than 8080 using command prompt in Windows?

Add the following two lines after DAEMON_ARGS in the file /etc/init.d/jenkins

HTTP_PORT=8010
JENKINS_ARGS="--httpPort=$HTTP_PORT"

What is the best way to tell if a character is a letter or number in Java without using regexes?

As the answers indicate (if you examine them carefully!), your question is ambiguous. What do you mean by "an A-z letter" or a digit?

If you want to know if a character is a Unicode letter or digit, then use the Character.isLetter and Character.isDigit methods.
If you want to know if a character is an ASCII letter or digit, then the best thing to do is to test by comparing with the character ranges 'a' to 'z', 'A' to 'Z' and '0' to '9'.

Note that all ASCII letters / digits are Unicode letters / digits ... but there are many Unicode letters / digits characters that are not ASCII. For example, accented letters, cyrillic, sanskrit, ...

The general solution is to do this:

Character.UnicodeBlock block = Character.UnicodeBlock.of(someCodePoint);

and then test to see if the block is one of the ones that you are interested in. In some cases you will need to test for multiple blocks. For example, there are (at least) 4 code blocks for Cyrillic characters and 7 for Latin. The Character.UnicodeBlock class defines static constants for well-known blocks; see the javadocs.

Note that any code point will be in at most one block.

Using number as "index" (JSON)

JSON is "JavaScript Object Notation". JavaScript specifies its keys must be strings or symbols.

The following quotation from MDN Docs uses the terms "key/property" to refer to what I more often hear termed as "key/value".

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures#Objects

In JavaScript, objects can be seen as a collection of properties. With the object literal syntax, a limited set of properties are initialized; then properties can be added and removed. Property values can be values of any type, including other objects, which enables building complex data structures. Properties are identified using key values. A key value is either a String or a Symbol value.

Is there more to an interface than having the correct methods

What makes interfaces useful is not the fact that "you can change your mind and use a different implementation later and only have to change the one place where the object is created". That's a non-issue.

The real point is already in the name: they define an interface that anyone at all can implement to use all code that operates on that interface. The best example is java.util.Collections which provides all kinds of useful methods that operate exclusively on interfaces, such as sort() or reverse() for List. The point here is that this code can now be used to sort or reverse any class that implements the List interfaces - not just ArrayList and LinkedList, but also classes that you write yourself, which may be implemented in a way the people who wrote java.util.Collections never imagined.

In the same way, you can write code that operates on well-known interfaces, or interfaces you define, and other people can use your code without having to ask you to support their classes.

Another common use of interfaces is for Callbacks. For example, java.swing.table.TableCellRenderer, which allows you to influence how a Swing table displays the data in a certain column. You implement that interface, pass an instance to the JTable, and at some point during the rendering of the table, your code will get called to do its stuff.

Two Divs on the same row and center align both of them

Better way till now:

If you give display:inline-block; to inner divs then child elements of inner divs will also get this property and disturb alignment of inner divs.
Better way is to use two different classes for inner divs with width, margin and float.

Best way till now:

Use flexbox.

http://css-tricks.com/snippets/css/a-guide-to-flexbox/

Cannot uninstall angular-cli

Updating Angular CLI

https://github.com/angular/angular-cli#updating-angular-cli

If you're using Angular CLI 1.0.0-beta.28 or less, you need to uninstall angular-cli package first.

npm uninstall -g angular-cli
npm uninstall -g @angular/cli
npm cache clean
npm install -g @angular/cli@latest

Then when it gets done successfully you may try:

ng --version

Transport endpoint is not connected

So interestingly enough this error "Transport endpoint is not connected" was caused by my having more than one Veracrypt device mounted. I closed the extra device and suddenly I had access to the drive. Hmm..

Global variables in header file

There are 3 scenarios, you describe:

with 2 .c files and with int i; in the header.
With 2 .c files and with int i=100; in the header (or any other value; that doesn't matter).
With 1 .c file and with int i=100; in the header.

In each scenario, imagine the contents of the header file inserted into the .c file and this .c file compiled into a .o file and then these linked together.

Then following happens:

works fine because of the already mentioned "tentative definitions": every .o file contains one of them, so the linker says "ok".
doesn't work, because both .o files contain a definition with a value, which collide (even if they have the same value) - there may be only one with any given name in all .o files which are linked together at a given time.
works of course, because you have only one .o file and so no possibility for collision.

IMHO a clean thing would be

to put either extern int i; or just int i; into the header file,
and then to put the "real" definition of i (namely int i = 100;) into file1.c. In this case, this initialization gets used at the start of the program and the corresponding line in main() can be omitted. (Besides, I hope the naming is only an example; please don't name any global variables as i in real programs.)

How to create a DataFrame of random integers with Pandas?

The recommended way to create random integers with NumPy these days is to use numpy.random.Generator.integers. (documentation)

import numpy as np
import pandas as pd

rng = np.random.default_rng()
df = pd.DataFrame(rng.integers(0, 100, size=(100, 4)), columns=list('ABCD'))
df
----------------------
      A    B    C    D
 0   58   96   82   24
 1   21    3   35   36
 2   67   79   22   78
 3   81   65   77   94
 4   73    6   70   96
... ...  ...  ...  ...
95   76   32   28   51
96   33   68   54   77
97   76   43   57   43
98   34   64   12   57
99   81   77   32   50
100 rows × 4 columns

How do I kill all the processes in Mysql "show processlist"?

mysqladmin pr -u 'USERNAME' -p'PASSWORD' | awk '$2~/^[0-9]+/{print $2}' | xargs -i mysqladmin -u 'USERNAME' -p'PASSWORD' kill {}

How can my iphone app detect its own version number?

This is a good thing to handle with a revision control system. That way when you get a bug report from a user, you can check out that revision of code and (hopefully) reproduce the bug running the exact same code as the user.

The idea is that every time you do a build, you will run a script that gets the current revision number of your code and updates a file within your project (usually with some form of token replacement). You can then write an error handling routine that always includes the revision number in the error output, or you can display it on an "About" page.

How to stop and restart memcached server?

if linux

if install by apt-get

service memcached stop
service memcached restart

if install by source code

Usage: /etc/init.d/memcached {start|stop|restart|force-reload|status}

can also simply kill $pid to stop

Filtering DataGridView without changing datasource

I just spent an hour on a similar problem. For me the answer turned out to be embarrassingly simple.

(dataGridViewFields.DataSource as DataTable).DefaultView.RowFilter = string.Format("Field = '{0}'", textBoxFilter.Text);

CURRENT_TIMESTAMP in milliseconds

For mysql:

SELECT (UNIX_TIMESTAMP() * 1000) AS unix_now_in_microseconds; --- 1600698677000

How to add reference to a method parameter in javadoc?

As far as I can tell after reading the docs for javadoc there is no such feature.

Don't use <code>foo</code> as recommended in other answers; you can use {@code foo}. This is especially good to know when you refer to a generic type such as {@code Iterator<String>} -- sure looks nicer than <code>Iterator<String></code>, doesn't it!

Centering text in a table in Twitter Bootstrap

The .table td 's text-align is set to left, rather than center.

Adding this should center all your tds:

.table td {
   text-align: center;   
}

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@import url('https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css');_x000D_
table,_x000D_
thead,_x000D_
tr,_x000D_
tbody,_x000D_
th,_x000D_
td {_x000D_
  text-align: center;_x000D_
}_x000D_
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.table td {_x000D_
  text-align: center;_x000D_
}

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<table class="table">_x000D_
  <thead>_x000D_
    <tr>_x000D_
      <th>1</th>_x000D_
      <th>1</th>_x000D_
      <th>1</th>_x000D_
      <th>1</th>_x000D_
      <th>2</th>_x000D_
      <th>2</th>_x000D_
      <th>2</th>_x000D_
      <th>2</th>_x000D_
      <th>3</th>_x000D_
      <th>3</th>_x000D_
      <th>3</th>_x000D_
      <th>3</th>_x000D_
    </tr>_x000D_
  </thead>_x000D_
  <tbody>_x000D_
    <tr>_x000D_
      <td colspan="4">Lorem</td>_x000D_
      <td colspan="4">ipsum</td>_x000D_
      <td colspan="4">dolor</td>_x000D_
    </tr>_x000D_
  </tbody>_x000D_
</table>

_x000D_

Updated JSFIDDLE

What are the ways to sum matrix elements in MATLAB?

You are trying to sum up all the elements of 2-D Array

In Matlab use

Array_Sum = sum(sum(Array_Name));

ViewDidAppear is not called when opening app from background

I think registering for the UIApplicationWillEnterForegroundNotification is risky as you may end up with more than one controller reacting to that notification. Nothing garanties that these controllers are still visible when the notification is received.

Here is what I do: I force call viewDidAppear on the active controller directly from the App's delegate didBecomeActive method:

Add the code below to - (void)applicationDidBecomeActive:(UIApplication *)application

UIViewController *activeController = window.rootViewController;
if ([activeController isKindOfClass:[UINavigationController class]]) {
    activeController = [(UINavigationController*)window.rootViewController topViewController];
}
[activeController viewDidAppear:NO];

How can I find the dimensions of a matrix in Python?

The number of rows of a list of lists would be: len(A) and the number of columns len(A[0]) given that all rows have the same number of columns, i.e. all lists in each index are of the same size.

subtract time from date - moment js

Michael Richardson's solution is great. If you would like to subtract dates (because Google will point you here if you search for it), you could also say:

var date1 = moment( "2014-06-07 00:03:00" );
var date2 = moment( "2014-06-07 09:22:00" );

differenceInMs = date2.diff(date1); // diff yields milliseconds
duration = moment.duration(differenceInMs); // moment.duration accepts ms
differenceInMinutes = duration.asMinutes(); // if you would like to have the output 559

Delaying a jquery script until everything else has loaded

Have you tried loading all the initialization functions using the $().ready, running the jQuery function you wanted last?

Perhaps you can use setTimeout() on the $().ready function you wanted to run, calling the functionality you wanted to load.

Or, use setInterval() and have the interval check to see if all the other load functions have completed (store the status in a boolean variable). When conditions are met, you could cancel the interval and run the load function.

Get Application Directory

PackageManager m = getPackageManager();
String s = getPackageName();
PackageInfo p = m.getPackageInfo(s, 0);
s = p.applicationInfo.dataDir;

If eclipse worries about an uncaught NameNotFoundException, you can use:

PackageManager m = getPackageManager();
String s = getPackageName();
try {
    PackageInfo p = m.getPackageInfo(s, 0);
    s = p.applicationInfo.dataDir;
} catch (PackageManager.NameNotFoundException e) {
    Log.w("yourtag", "Error Package name not found ", e);
}

How do I create a MessageBox in C#?

I got the same error 'System.Windows.Forms.MessageBox' is a 'type' but is used like a 'variable', even if using:

MessageBox.Show("Hello, World!");

I guess my initial attempts with invalid syntax caused some kind of bug and I ended up fixing it by adding a space between "MessageBox.Show" and the brackets ():

MessageBox.Show ("Hello, World!");

Now using the original syntax without the extra space works again:

MessageBox.Show("Hello, World!");

Are duplicate keys allowed in the definition of binary search trees?

If your binary search tree is a red black tree, or you intend to any kind of "tree rotation" operations, duplicate nodes will cause problems. Imagine your tree rule is this:

left < root <= right

Now imagine a simple tree whose root is 5, left child is nil, and right child is 5. If you do a left rotation on the root you end up with a 5 in the left child and a 5 in the root with the right child being nil. Now something in the left tree is equal to the root, but your rule above assumed left < root.

I spent hours trying to figure out why my red/black trees would occasionally traverse out of order, the problem was what I described above. Hopefully somebody reads this and saves themselves hours of debugging in the future!

auto create database in Entity Framework Core

If you have created the migrations, you could execute them in the Startup.cs as follows.

 public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
 {
      using (var serviceScope = app.ApplicationServices.GetService<IServiceScopeFactory>().CreateScope())
      {
            var context = serviceScope.ServiceProvider.GetRequiredService<ApplicationDbContext>();
            context.Database.Migrate();
      }
      
      ...

This will create the database and the tables using your added migrations.

If you're not using Entity Framework Migrations, and instead just need your DbContext model created exactly as it is in your context class at first run, then you can use:

 public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
 {
      using (var serviceScope = app.ApplicationServices.GetService<IServiceScopeFactory>().CreateScope())
      {
            var context = serviceScope.ServiceProvider.GetRequiredService<ApplicationDbContext>();
            context.Database.EnsureCreated();
      }
      
      ...

Instead.

If you need to delete your database prior to making sure it's created, call:

            context.Database.EnsureDeleted();

Just before you call EnsureCreated()

Adapted from: http://docs.identityserver.io/en/latest/quickstarts/7_entity_framework.html?highlight=entity

How to fix 'fs: re-evaluating native module sources is not supported' - graceful-fs

I was able to fix it by:

updating by package.json
deleting the node_modules folder
executing npm install

RSA: Get exponent and modulus given a public key

Mostly for my own reference, here's how you get it from a private key generated by ssh-keygen

openssl rsa -text -noout -in ~/.ssh/id_rsa

Of course, this only works with the private key.

How to remove a field completely from a MongoDB document?

I was trying to do something similar to this but instead remove the column from an embedded document. It took me a while to find a solution and this was the first post I came across so I thought I would post this here for anyone else trying to do the same.

So lets say instead your data looks like this:

{ 
  name: 'book',
  tags: [
    {
      words: ['abc','123'],
      lat: 33,
      long: 22
    }, {
      words: ['def','456'],
      lat: 44,
      long: 33
    }
  ]
}

To remove the column words from the embedded document, do this:

db.example.update(
  {'tags': {'$exists': true}},
  { $unset: {'tags.$[].words': 1}},
  {multi: true}
)

or using the updateMany

db.example.updateMany(
  {'tags': {'$exists': true}},
  { $unset: {'tags.$[].words': 1}}
)

The $unset will only edit it if the value exists but it will not do a safe navigation (it wont check if tags exists first) so the exists is needed on the embedded document.

This uses the all positional operator ($[]) which was introduced in version 3.6

How do you convert Html to plain text?

If you have data that has HTML tags and you want to display it so that a person can SEE the tags, use HttpServerUtility::HtmlEncode.

If you have data that has HTML tags in it and you want the user to see the tags rendered, then display the text as is. If the text represents an entire web page, use an IFRAME for it.

If you have data that has HTML tags and you want to strip out the tags and just display the unformatted text, use a regular expression.

XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP

If you use the WebStorm Javascript IDE, you can just open your project from WebStorm in your browser. WebStorm will automatically start a server and you won't get any of these errors anymore, because you are now accessing the files with the allowed/supported protocols (HTTP).

How to implement a SQL like 'LIKE' operator in java?

This's my take on this, it's in Kotlin but can be converted to Java with little effort:

val percentageRegex = Regex("""(?<!\\)%""")
val underscoreRegex = Regex("""(?<!\\)_""")

infix fun String.like(predicate: String): Boolean {

    //Split the text by every % not preceded by a slash.
    //We transform each slice before joining them with .* as a separator.
    return predicate.split(percentageRegex).joinToString(".*") { percentageSlice ->

        //Split the text by every _ not preceded by a slash.
        //We transform each slice before joining them with . as a separator.
        percentageSlice.split(underscoreRegex).joinToString(".") { underscoreSlice ->

            //Each slice is wrapped in "Regex quotes" to ignore all
            // the metacharacters they contain.
            //We also remove the slashes from the escape sequences
            // since they are now treated literally.
            Pattern.quote(
                underscoreSlice.replace("\\_", "_").replace("\\%", "%")
            )
        }

    }.let { "^$it$" }.toRegex().matches(this@like)
}

It might not be the most performant of all the solutions here, but it's probably the most accurate.

It ignores all the other Regex metacharacters other than % and _ and also supports escaping them with a slash.

Full width layout with twitter bootstrap

Because the accepted answer isn't on the same planet as BS3, I'll share what I'm using to achieve nearly full-width capabilities.

First off, this is cheating. It's not really fluid width - but it appears to be - depending on the size of the screen viewing the site.

The problem with BS3 and fluid width sites is that they have taken this "mobile first" approach, which requires that they define every freaking screen width up to what they consider to be desktop (1200px) I'm working on a laptop with a 1900px wide screen - so I end up with 350px on either side of the content at what BS3 thinks is a desktop sized width.

They have defined 10 screen widths (really only 5, but anyway). I don't really feel comfortable changing those, because they are common widths. So, I chose to define some extra widths for BS to choose from when deciding the width of the container class.

The way I use BS is to take all of the Bootstrap provided LESS files, omit the variables.less file to provide my own, and add one of my own to the end to override the things I want to change. Within my less file, I add the following to achieve 2 common screen width settings:

@media screen and (min-width: 1600px) {
    .container {
        max-width: (1600px - @grid-gutter-width);
    }
}
@media screen and (min-width: 1900px) {
    .container {
        max-width: (1900px - @grid-gutter-width);
    }
}

These two settings set the example for what you need to do to achieve different screen widths. Here, you get full width at 1600px, and 1900px. Any less than 1600 - BS falls back to the 1200px width, then to 768px and so forth - down to phone size.

If you have larger to support, just create more @media screen statements like these. If you're building the CSS instead, you'll want to determine what gutter width was used and subtract it from your target screen width.

Update:

Bootstrap 3.0.1 and up (so far) - it's as easy as setting @container-large-desktop to 100%

How to write a multidimensional array to a text file?

Pickle is best for these cases. Suppose you have a ndarray named x_train. You can dump it into a file and revert it back using the following command:

import pickle

###Load into file
with open("myfile.pkl","wb") as f:
    pickle.dump(x_train,f)

###Extract from file
with open("myfile.pkl","rb") as f:
    x_temp = pickle.load(f)

How do I empty an input value with jQuery?

To make values empty you can do the following:

 $("#element").val('');

To get the selected value you can do:

var value = $("#element").val();

Where #element is the id of the element you wish to select.

Selection with .loc in python

It's pandas label-based selection, as explained here: https://pandas.pydata.org/pandas-docs/stable/indexing.html#selection-by-label

The boolean array is basically a selection method using a mask.

add allow_url_fopen to my php.ini using .htaccess

Try this, but I don't think it will work because you're not supposed to be able to change this

Put this line in an htaccess file in the directory you want the setting to be enabled:

php_value allow_url_fopen On

Note that this setting will only apply to PHP file's in the same directory as the htaccess file.

As an alternative to using url_fopen, try using curl.

How to generate a random alpha-numeric string

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

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

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

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

        find(n, len);
    }

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

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

Mockito: Mock private field initialization

In case you use Spring Test try org.springframework.test.util.ReflectionTestUtils

 ReflectionTestUtils.setField(testObject, "person", mockedPerson);

Using print statements only to debug

I don't know about others, but I was used to define a "global constant" (DEBUG) and then a global function (debug(msg)) that would print msg only if DEBUG == True.

Then I write my debug statements like:

debug('My value: %d' % value)

...then I pick up unit testing and never did this again! :)

How to make button fill table cell

For starters:

<p align='center'>
<table width='100%'>
<tr>
<td align='center'><form><input type=submit value="click me" style="width:100%"></form></td>
</tr>
</table>
</p>

Note, if the width of the input button is 100%, you wont need the attribute "align='center'" anymore.

This would be the optimal solution:

<p align='center'>
<table width='100%'>
<tr>
<td><form><input type=submit value="click me" style="width:100%"></form></td>
</tr>
</table>
</p>

How to Use -confirm in PowerShell

write-host does not have a -confirm parameter.

You can do it something like this instead:

    $caption = "Please Confirm"    
    $message = "Are you Sure You Want To Proceed:"
    [int]$defaultChoice = 0
    $yes = New-Object System.Management.Automation.Host.ChoiceDescription "&Yes", "Do the job."
    $no = New-Object System.Management.Automation.Host.ChoiceDescription "&No", "Do not do the job."
    $options = [System.Management.Automation.Host.ChoiceDescription[]]($yes, $no)
    $choiceRTN = $host.ui.PromptForChoice($caption,$message, $options,$defaultChoice)

if ( $choiceRTN -ne 1 )
{
   "Your Choice was Yes"
}
else
{
   "Your Choice was NO"
}

How do I make XAML DataGridColumns fill the entire DataGrid?

This will not expand the last column of the xaml grid to take the remaining space if AutoGeneratedColumns="True".

How do I echo and send console output to a file in a bat script?

I like atn's answer, but it was not as trivial for me to download as wintee, which is also open source and only gives the tee functionality (useful if you just want tee and not the entire set of unix utilities). I learned about this from davor's answer to Displaying Windows command prompt output and redirecting it to a file, where you also find reference to the unix utilities.

ImportError: No module named matplotlib.pyplot

You can install the matplotlib package in python 3 by doing this

python3 -m pip install matplotlib --user

It's working for me.

How to parse month full form string using DateFormat in Java?

val currentTime = Calendar.getInstance().time
SimpleDateFormat("MMMM", Locale.getDefault()).format(date.time)

LINQ to Entities does not recognize the method

If anyone is looking for a VB.Net answer (as I was initially), here it is:

Public Function IsSatisfied() As Expression(Of Func(Of Charity, String, String, Boolean))

Return Function(charity, name, referenceNumber) (String.IsNullOrWhiteSpace(name) Or
                                                         charity.registeredName.ToLower().Contains(name.ToLower()) Or
                                                         charity.alias.ToLower().Contains(name.ToLower()) Or
                                                         charity.charityId.ToLower().Contains(name.ToLower())) And
                                                    (String.IsNullOrEmpty(referenceNumber) Or
                                                     charity.charityReference.ToLower().Contains(referenceNumber.ToLower()))
End Function

How to increase space between dotted border dots

Here's a trick I've used on a recent project to achieve nearly anything I want with horizontal borders. I use <hr/> each time I need an horizontal border. The basic way to add a border to this hr is something like

 hr {border-bottom: 1px dotted #000;}

But if you want to take control of the border and, for example increase, the space between dots, you may try something like this:

hr {
height:14px; /* specify a height for this hr */
overflow:hidden;
}

And in the following, you create your border (here's an example with dots)

hr:after {
content:".......................................................................";
letter-spacing: 4px; /* Use letter-spacing to increase space between dots*/
}

This also means that you can add text-shadow to the dots, gradients etc. Anything you want...

Well, it works really great for horizontal borders. If you need vertical ones, you may specify a class for another hr and use the CSS3 rotation property.

jQuery: How to detect window width on the fly?

Put your if condition inside resize function:

var windowsize = $(window).width();

$(window).resize(function() {
  windowsize = $(window).width();
  if (windowsize > 440) {
    //if the window is greater than 440px wide then turn on jScrollPane..
      $('#pane1').jScrollPane({
         scrollbarWidth:15, 
         scrollbarMargin:52
      });
  }
});

Show all tables inside a MySQL database using PHP?

<?php
$dbname = 'mysql_dbname';
if (!mysql_connect('mysql_host', 'mysql_user', 'mysql_password')) {
echo 'Could not connect to mysql';
exit;
}
$sql = "SHOW TABLES FROM $dbname";
$result = mysql_query($sql);
if (!$result) {
echo "DB Error, could not list tables\n";
echo 'MySQL Error: ' . mysql_error();
exit;
}
while ($row = mysql_fetch_row($result)) {
echo "Table: {$row[0]}\n";
}
mysql_free_result($result);
?>
//Try This code is running perfectly !!!!!!!!!!

Can a java lambda have more than 1 parameter?

Some lambda function :

import org.junit.Test;
import java.awt.event.ActionListener;
import java.util.function.Function;

public class TestLambda {

@Test
public void testLambda() {

    System.out.println("test some lambda function");

    ////////////////////////////////////////////
    //1-any input | any output:
    //lambda define:
    Runnable lambda1 = () -> System.out.println("no parameter");
    //lambda execute:
    lambda1.run();


    ////////////////////////////////////////////
    //2-one input(as ActionEvent) | any output:
    //lambda define:
    ActionListener lambda2 = (p) -> System.out.println("One parameter as action");
    //lambda execute:
    lambda2.actionPerformed(null);


    ////////////////////////////////////////////
    //3-one input | by output(as Integer):
    //lambda define:
    Function<String, Integer> lambda3 = (p1) -> {
        System.out.println("one parameters: " + p1);
        return 10;
    };
    //lambda execute:
    lambda3.apply("test");


    ////////////////////////////////////////////
    //4-two input | any output
    //lambda define:
    TwoParameterFunctionWithoutReturn<String, Integer> lambda4 = (p1, p2) -> {
        System.out.println("two parameters: " + p1 + ", " + p2);
    };
    //lambda execute:
    lambda4.apply("param1", 10);


    ////////////////////////////////////////////
    //5-two input | by output(as Integer)
    //lambda define:
    TwoParameterFunctionByReturn<Integer, Integer> lambda5 = (p1, p2) -> {
        System.out.println("two parameters: " + p1 + ", " + p2);
        return p1 + p2;
    };
    //lambda execute:
    lambda5.apply(10, 20);


    ////////////////////////////////////////////
    //6-three input(Integer,Integer,String) | by output(as Integer)
    //lambda define:
    ThreeParameterFunctionByReturn<Integer, Integer, Integer> lambda6 = (p1, p2, p3) -> {
        System.out.println("three parameters: " + p1 + ", " + p2 + ", " + p3);
        return p1 + p2 + p3;
    };
    //lambda execute:
    lambda6.apply(10, 20, 30);

}


@FunctionalInterface
public interface TwoParameterFunctionWithoutReturn<T, U> {
    public void apply(T t, U u);
}

@FunctionalInterface
public interface TwoParameterFunctionByReturn<T, U> {
    public T apply(T t, U u);
}

@FunctionalInterface
public interface ThreeParameterFunctionByReturn<M, N, O> {
    public Integer apply(M m, N n, O o);
}
}

Chrome blocks different origin requests

This is a security update. If an attacker can modify some file in the web server (the JS one, for example), he can make every loaded pages to download another script (for example to keylog your password or steal your SessionID and send it to his own server).

To avoid it, the browser check the Same-origin policy

Your problem is that the browser is trying to load something with your script (with an Ajax request) that is on another domain (or subdomain). To avoid it (if it is on your own website) you can:

Copy the element on your own server (but it will be static).
You can change your HTTP header to accept Cross-Origin content. See the Access-Control-Allow-Origin documentation for more information.

Format numbers to strings in Python

Python 2.6+

It is possible to use the format() function, so in your case you can use:

return '{:02d}:{:02d}:{:.2f} {}'.format(hours, minutes, seconds, ampm)

There are multiple ways of using this function, so for further information you can check the documentation.

Python 3.6+

f-strings is a new feature that has been added to the language in Python 3.6. This facilitates formatting strings notoriously:

return f'{hours:02d}:{minutes:02d}:{seconds:.2f} {ampm}'

Normalize numpy array columns in python

If I understand correctly, what you want to do is divide by the maximum value in each column. You can do this easily using broadcasting.

Starting with your example array:

import numpy as np

x = np.array([[1000,  10,   0.5],
              [ 765,   5,  0.35],
              [ 800,   7,  0.09]])

x_normed = x / x.max(axis=0)

print(x_normed)
# [[ 1.     1.     1.   ]
#  [ 0.765  0.5    0.7  ]
#  [ 0.8    0.7    0.18 ]]

x.max(0) takes the maximum over the 0th dimension (i.e. rows). This gives you a vector of size (ncols,) containing the maximum value in each column. You can then divide x by this vector in order to normalize your values such that the maximum value in each column will be scaled to 1.

If x contains negative values you would need to subtract the minimum first:

x_normed = (x - x.min(0)) / x.ptp(0)

Here, x.ptp(0) returns the "peak-to-peak" (i.e. the range, max - min) along axis 0. This normalization also guarantees that the minimum value in each column will be 0.

Create Windows service from executable

Use NSSM( the non-Sucking Service Manager ) to run a .BAT or any .EXE file as a service.

http://nssm.cc/

Step 1: Download NSSM
Step 2: Install your sevice with nssm.exe install [serviceName]
Step 3: This will open a GUI which you will use to locate your executable

How do I set bold and italic on UILabel of iPhone/iPad?

With Swift 5

For style = BOLD

label.font = UIFont(name:"HelveticaNeue-Bold", size: 15.0)

For style = Medium

label.font = UIFont(name:"HelveticaNeue-Medium", size: 15.0)

For style = Thin

label.font = UIFont(name:"HelveticaNeue-Thin", size: 15.0)

MySQL Select Date Equal to Today

You can use the CONCAT with CURDATE() to the entire time of the day and then filter by using the BETWEEN in WHERE condition:

SELECT users.id, DATE_FORMAT(users.signup_date, '%Y-%m-%d') 
FROM users 
WHERE (users.signup_date BETWEEN CONCAT(CURDATE(), ' 00:00:00') AND CONCAT(CURDATE(), ' 23:59:59'))

Forbidden You don't have permission to access /wp-login.php on this server

Make sure the following lines are not in your wp.config

define( 'FORCE_SSL_LOGIN', true );
define( 'FORCE_SSL_ADMIN', true );
define( 'DISALLOW_FILE_EDIT', true );

I got locked out after deactivating iThemes security plugin

How to center cell contents of a LaTeX table whose columns have fixed widths?

\usepackage{array} in the preamble

then this:

\begin{tabular}{| >{\centering\arraybackslash}m{1in} | >{\centering\arraybackslash}m{1in} |}

note that the "m" for fixed with column is provided by the array package, and will give you vertical centering (if you don't want this just go back to "p"

Installing mcrypt extension for PHP on OSX Mountain Lion

This is what I did:

$ wget http://sourceforge.net/projects/mcrypt/files/Libmcrypt/2.5.8/libmcrypt-2.5.8.tar.gz/download
$ tar xzvf libmcrypt-2.5.8.tar.gz
$ ./configure
$ make
$ sudo make install

$ brew install autoconf

$ wget file:///Users/rmatikolai/Downloads/php-5.4.24.tar.bz2
$ tar xjvf php-5.4.24.tar.bz2
$ cd php-5.4.24/ext/mcrypt
$ phpize
$ ./configure # this is the step which fails without the above dependencies
$ make
$ make test
$ sudo make install


$ sudo cp /private/etc/php.ini.default /private/etc/php.ini
$ sudo vi /private/etc/php.ini

Next, you need to add the line:

extension=mcrypt.so

$ sudo apachectl restart

open link of google play store in mobile version android

Below code may helps you for display application link of google play sore in mobile version.

For Application link :

Uri uri = Uri.parse("market://details?id=" + mContext.getPackageName());
Intent myAppLinkToMarket = new Intent(Intent.ACTION_VIEW, uri);

  try {
        startActivity(myAppLinkToMarket);

      } catch (ActivityNotFoundException e) {

        //the device hasn't installed Google Play
        Toast.makeText(Setting.this, "You don't have Google Play installed", Toast.LENGTH_LONG).show();
              }

For Developer link :

Uri uri = Uri.parse("market://search?q=pub:" + YourDeveloperName);
Intent myAppLinkToMarket = new Intent(Intent.ACTION_VIEW, uri);

            try {

                startActivity(myAppLinkToMarket);

            } catch (ActivityNotFoundException e) {

                //the device hasn't installed Google Play
                Toast.makeText(Settings.this, "You don't have Google Play installed", Toast.LENGTH_LONG).show();

            }

Link to add to Google calendar

For the next person Googling this topic, I've written a small NPM package to make it simple to generate Google Calendar URLs. It includes TypeScript type definitions, for those who need that. Hope it helps!

https://www.npmjs.com/package/google-calendar-url

How to add color to Github's README.md file

Unfortunately, this is currently not possible.

The GitHub Markdown documentation has no mention of 'color', 'css', 'html', or 'style'.

While some Markdown processors (e.g. the one used in Ghost) allow for HTML, such as <span style="color:orange;">Word up</span>, GitHub's discards any HTML.

If it's imperative that you use color in your readme, your README.md could simply refer users to a README.html. The trade-off for this, of course, is accessibility.

Android emulator: How to monitor network traffic?

I would suggest you use Wireshark.

Steps:

Install Wireshark.

Select the network connection that you are using for the calls(for eg, select the Wifi if you are using it)

There will be many requests and responses, close extra applications.

Usually the requests are in green color, once you spot your request, copy the destination address and use the filter on top by typing ip.dst==52.187.182.185 by putting the destination address.

You can make use of other filtering techniques mentioned here to get specific traffic.

c# datagridview doubleclick on row with FullRowSelect

I think you are looking for this: RowHeaderMouseDoubleClick event

private void DgwModificar_RowHeaderMouseDoubleClick(object sender, DataGridViewCellMouseEventArgs e) {
...
}

to get the row index:

int indice = e.RowIndex

Difference between \b and \B in regex

\b is a zero-width word boundary. Specifically:

Matches at the position between a word character (anything matched by \w) and a non-word character (anything matched by [^\w] or \W) as well as at the start and/or end of the string if the first and/or last characters in the string are word characters.

Example: .\b matches c in abc

\B is a zero-width non-word boundary. Specifically:

Matches at the position between two word characters (i.e the position between \w\w) as well as at the position between two non-word characters (i.e. \W\W).

Example: \B.\B matches b in abc

See regular-expressions.info for more great regex info

UPDATE with CASE and IN - Oracle

"The list are variables/paramaters that is pre-defined as comma separated lists". Do you mean that your query is actually

UPDATE tab1   SET budgpost_gr1=     
CASE  WHEN (budgpost in ('1001,1012,50055'))  THEN 'BP_GR_A'   
      WHEN (budgpost in ('5,10,98,0'))  THEN 'BP_GR_B'  
      WHEN (budgpost in ('11,876,7976,67465'))     
      ELSE 'Missing' END`

If so, you need a function to take a string and parse it into a list of numbers.

create type tab_num is table of number;

create or replace function f_str_to_nums (i_str in varchar2) return tab_num is
  v_tab_num tab_num := tab_num();
  v_start   number := 1;
  v_end     number;
  v_delim   VARCHAR2(1) := ',';
  v_cnt     number(1) := 1;
begin
  v_end := instr(i_str||v_delim,v_delim,1, v_start);
  WHILE v_end > 0 LOOP
    v_cnt := v_cnt + 1;
    v_tab_num.extend;
    v_tab_num(v_tab_num.count) := 
                  substr(i_str,v_start,v_end-v_start);
    v_start := v_end + 1;
    v_end := instr(i_str||v_delim,v_delim,v_start);
  END LOOP;
  RETURN v_tab_num;
end;
/

Then you can use the function like so:

select column_id, 
   case when column_id in 
     (select column_value from table(f_str_to_nums('1,2,3,4'))) then 'red' 
   else 'blue' end
from  user_tab_columns
where table_name = 'EMP'

Convert MySql DateTime stamp into JavaScript's Date format

A quick search in google provided this:

 function mysqlTimeStampToDate(timestamp) {
    //function parses mysql datetime string and returns javascript Date object
    //input has to be in this format: 2007-06-05 15:26:02
    var regex=/^([0-9]{2,4})-([0-1][0-9])-([0-3][0-9]) (?:([0-2][0-9]):([0-5][0-9]):([0-5][0-9]))?$/;
    var parts=timestamp.replace(regex,"$1 $2 $3 $4 $5 $6").split(' ');
    return new Date(parts[0],parts[1]-1,parts[2],parts[3],parts[4],parts[5]);
  }

Source:http://snippets.dzone.com/posts/show/4132

dbms_lob.getlength() vs. length() to find blob size in oracle

length and dbms_lob.getlength return the number of characters when applied to a CLOB (Character LOB). When applied to a BLOB (Binary LOB), dbms_lob.getlength will return the number of bytes, which may differ from the number of characters in a multi-byte character set.

As the documentation doesn't specify what happens when you apply length on a BLOB, I would advise against using it in that case. If you want the number of bytes in a BLOB, use dbms_lob.getlength.

JavaScript checking for null vs. undefined and difference between == and ===

Try With Different Logic. You can use bellow code for check all four(4) condition for validation like not null, not blank, not undefined and not zero only use this code (!(!(variable))) in javascript and jquery.

function myFunction() {
var data;  //The Values can be like as null, blank, undefined, zero you can test

if(!(!(data)))
{
   //If data has valid value
    alert("data "+data);
} 
else 
{
    //If data has null, blank, undefined, zero etc.
    alert("data is "+data);
}

}

How to select id with max date group by category in PostgreSQL?

Another approach is to use the first_value window function: http://sqlfiddle.com/#!12/7a145/14

SELECT DISTINCT
  first_value("id") OVER (PARTITION BY "category" ORDER BY "date" DESC) 
FROM Table1
ORDER BY 1;

... though I suspect hims056's suggestion will typically perform better where appropriate indexes are present.

A third solution is:

SELECT
  id
FROM (
  SELECT
    id,
    row_number() OVER (PARTITION BY "category" ORDER BY "date" DESC) AS rownum
  FROM Table1
) x
WHERE rownum = 1;

How to return value from function which has Observable subscription inside?

The decent way would be to return the observable from a function and subscribe to it wherever required, because observables are lazy, they will start emitting values only when they are subscribed.

Here I have one more interesting event driven solution, which I initially used to play around with. Following example does this by using "events" module of nodejs. You can use it with other frameworks where similar module exists(Note: Syntax and style might change depending on module used).

var from =require("rxjs").from;
var map = require("rxjs/operators").map;
var EventEmitter = require("events");

function process(event) {
    from([1,2,3]).pipe(
        map(val => `The number is:: ${val}`)
    ).subscribe((data) => {
       event.emit("Event1", data); //emit value received in subscribe to the "Event1" listener
    });
}

function main() {
   class Emitter extends EventEmitter{};
    var event = new Emitter(); //creating an event
    event.on("Event1", (data)=>{ //listening to the event of name "Event1" and callback to log returned result
        console.log(data); //here log, print, play with the data you receive
    });
    process(event); //pass the event to the function which returns observable.
}

main(); //invoke main function

It is just an example to showcase an idea where we can pass data from different places by method of emitting and listening. This is also known as event-driven code.

Converting NumPy array into Python List structure?

tolist() works fine even if encountered a nested array, say a pandas DataFrame;

my_list = [0,1,2,3,4,5,4,3,2,1,0]
my_dt = pd.DataFrame(my_list)
new_list = [i[0] for i in my_dt.values.tolist()]

print(type(my_list),type(my_dt),type(new_list))

Select All as default value for Multivalue parameter

Try setting the parameters' "default value" to use the same query as the "available values". In effect it provides every single "available value" as a "default value" and the "Select All" option is automatically checked.

How to directly execute SQL query in C#?

Something like this should suffice, to do what your batch file was doing (dumping the result set as semi-colon delimited text to the console):

// sqlcmd.exe
// -S .\PDATA_SQLEXPRESS
// -U sa
// -P 2BeChanged!
// -d PDATA_SQLEXPRESS
// -s ; -W -w 100
// -Q "SELECT tPatCulIntPatIDPk, tPatSFirstname, tPatSName, tPatDBirthday  FROM  [dbo].[TPatientRaw] WHERE tPatSName = '%name%' "

DataTable dt            = new DataTable() ;
int       rows_returned ;

const string credentials = @"Server=(localdb)\.\PDATA_SQLEXPRESS;Database=PDATA_SQLEXPRESS;User ID=sa;Password=2BeChanged!;" ;
const string sqlQuery = @"
  select tPatCulIntPatIDPk ,
         tPatSFirstname    ,
         tPatSName         ,
         tPatDBirthday
  from dbo.TPatientRaw
  where tPatSName = @patientSurname
  " ;

using ( SqlConnection connection = new SqlConnection(credentials) )
using ( SqlCommand    cmd        = connection.CreateCommand() )
using ( SqlDataAdapter sda       = new SqlDataAdapter( cmd ) )
{
  cmd.CommandText = sqlQuery ;
  cmd.CommandType = CommandType.Text ;
  connection.Open() ;
  rows_returned = sda.Fill(dt) ;
  connection.Close() ;
}

if ( dt.Rows.Count == 0 )
{
  // query returned no rows
}
else
{

  //write semicolon-delimited header
  string[] columnNames = dt.Columns
                           .Cast<DataColumn>()
                           .Select( c => c.ColumnName )
                           .ToArray()
                           ;
  string   header      = string.Join("," , columnNames) ;
  Console.WriteLine(header) ;

  // write each row
  foreach ( DataRow dr in dt.Rows )
  {

    // get each rows columns as a string (casting null into the nil (empty) string
    string[] values = new string[dt.Columns.Count];
    for ( int i = 0 ; i < dt.Columns.Count ; ++i )
    {
      values[i] = ((string) dr[i]) ?? "" ; // we'll treat nulls as the nil string for the nonce
    }

    // construct the string to be dumped, quoting each value and doubling any embedded quotes.
    string data = string.Join( ";" , values.Select( s => "\""+s.Replace("\"","\"\"")+"\"") ) ;
    Console.WriteLine(values);

  }

}

Refused to display in a frame because it set 'X-Frame-Options' to 'SAMEORIGIN'

I did the below changes and works fine for me.

Just add the attribute <iframe src="URL" target="_parent" />

_parent: this would open embedded page in same window.

_blank: In different tab

Detect if PHP session exists

If you are on php 5.4+, it is cleaner to use session_status():

if (session_status() == PHP_SESSION_ACTIVE) {
  echo 'Session is active';
}

PHP_SESSION_DISABLED if sessions are disabled.
PHP_SESSION_NONE if sessions are enabled, but none exists.
PHP_SESSION_ACTIVE if sessions are enabled, and one exists.

Simulating a click in jQuery/JavaScript on a link

Try this

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

and you can use it like

submitRequest("target-element-id");

Remove duplicates from a List<T> in C#

In Java (I assume C# is more or less identical):

list = new ArrayList<T>(new HashSet<T>(list))

If you really wanted to mutate the original list:

List<T> noDupes = new ArrayList<T>(new HashSet<T>(list));
list.clear();
list.addAll(noDupes);

To preserve order, simply replace HashSet with LinkedHashSet.

lodash: mapping array to object

Yep it is here, using _.reduce

var params = [
    { name: 'foo', input: 'bar' },
    { name: 'baz', input: 'zle' }
];

_.reduce(params , function(obj,param) {
 obj[param.name] = param.input
 return obj;
}, {});

Installing Oracle Instant Client

If you want to use SQL Server Management Studio, you want to install the full Oracle client, not the Instant Client. The full Oracle client is on the same download page as the Oracle database. Assuming that you are installing on a 64-bit version of Windows, I expect you want the "Oracle Database 11g Release 2 Client (11.2.0.1.0) for Microsoft Windows (x64)" download. This is several hundred MB rather than a couple of MB for the Instant Client.

Command to close an application of console?

By close, do you mean you want the current instance of the console app to close, or do you want the application process, to terminate? Missed that all important exit code:

Environment.Exit(0);

Or to close the current instance of the form:

this.Close();

Useful link.

Retrieve Button value with jQuery

You can also use the new HTML5 custom data- attributes.

<script type="text/javascript">
$(document).ready(function() {
    $('.my_button').click(function() {
        alert($(this).attr('data-value'));
    });
});
</script>

<button class="my_button" name="buttonName" data-value="buttonValue">Button Label</button>

Cannot find reference 'xxx' in init.py - Python / Pycharm

You can mark source directory as a source root like so:

Right-click on source directory
Mark Directory As --> Source Root
File --> Invalidate Caches / Restart... -> Invalidate and Restart

How To Make Circle Custom Progress Bar in Android

Try this piece of code to create circular progress bar(pie chart). pass it integer value to draw how many percent of filling area. :)

private void circularImageBar(ImageView iv2, int i) {

    Bitmap b = Bitmap.createBitmap(300, 300,Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(b); 
    Paint paint = new Paint();

        paint.setColor(Color.parseColor("#c4c4c4"));
        paint.setStrokeWidth(10);
        paint.setAntiAlias(true);
        paint.setStyle(Paint.Style.STROKE);
        canvas.drawCircle(150, 150, 140, paint);
        paint.setColor(Color.parseColor("#FFDB4C"));
        paint.setStrokeWidth(10);   
        paint.setStyle(Paint.Style.FILL);
        final RectF oval = new RectF();
        paint.setStyle(Paint.Style.STROKE);
        oval.set(10,10,290,290);
        canvas.drawArc(oval, 270, ((i*360)/100), false, paint);
        paint.setStrokeWidth(0);    
        paint.setTextAlign(Align.CENTER);
        paint.setColor(Color.parseColor("#8E8E93")); 
        paint.setTextSize(140);
        canvas.drawText(""+i, 150, 150+(paint.getTextSize()/3), paint); 
        iv2.setImageBitmap(b);
}

Get current controller in view

Just use:

ViewContext.Controller.GetType().Name

This will give you the whole Controller's Name

How to use the ProGuard in Android Studio?

NB.: Now instead of

runProguard false

you'll need to use

minifyEnabled false

Change working directory in my current shell context when running Node script

What you are trying to do is not possible. The reason for this is that in a POSIX system (Linux, OSX, etc), a child process cannot modify the environment of a parent process. This includes modifying the parent process's working directory and environment variables.

When you are on the commandline and you go to execute your Node script, your current process (bash, zsh, whatever) spawns a new process which has it's own environment, typically a copy of your current environment (it is possible to change this via system calls; but that's beyond the scope of this reply), allowing that process to do whatever it needs to do in complete isolation. When the subprocess exits, control is handed back to your shell's process, where the environment hasn't been affected.

There are a lot of reasons for this, but for one, imagine that you executed a script in the background (via ./foo.js &) and as it ran, it started changing your working directory or overriding your PATH. That would be a nightmare.

If you need to perform some actions that require changing your working directory of your shell, you'll need to write a function in your shell. For example, if you're running Bash, you could put this in your ~/.bash_profile:

do_cool_thing() {
  cd "/Users"
  echo "Hey, I'm in $PWD"
}

and then this cool thing is doable:

$ pwd
/Users/spike
$ do_cool_thing
Hey, I'm in /Users
$ pwd
/Users

If you need to do more complex things in addition, you could always call out to your nodejs script from that function.

This is the only way you can accomplish what you're trying to do.

Align text in JLabel to the right

This can be done in two ways.

JLabel Horizontal Alignment

You can use the JLabel constructor:

JLabel(String text, int horizontalAlignment)

To align to the right:

JLabel label = new JLabel("Telephone", SwingConstants.RIGHT);

JLabel also has setHorizontalAlignment:

label.setHorizontalAlignment(SwingConstants.RIGHT);

This assumes the component takes up the whole width in the container.

Using Layout

A different approach is to use the layout to actually align the component to the right, whilst ensuring they do not take the whole width. Here is an example with BoxLayout:

    Box box = Box.createVerticalBox();
    JLabel label1 = new JLabel("test1, the beginning");
    label1.setAlignmentX(Component.RIGHT_ALIGNMENT);
    box.add(label1);

    JLabel label2 = new JLabel("test2, some more");
    label2.setAlignmentX(Component.RIGHT_ALIGNMENT);
    box.add(label2);

    JLabel label3 = new JLabel("test3");
    label3.setAlignmentX(Component.RIGHT_ALIGNMENT);
    box.add(label3);


    add(box);

How to force a UIViewController to Portrait orientation in iOS 6

I did not test it myself, but the documentation states that you can now override those methods: supportedInterfaceOrientations and preferredInterfaceOrientationForPresentation.

You can probably achieve what you want y setting only the orientation that you want in those methods.

How to enable C++17 compiling in Visual Studio?

Visual Studio 2015 Update 3 does not support the C++17 feature you are looking for (emplace_back() returning a reference).

Support For C++11/14/17 Features (Modern C++)

C++11/14/17 Features In VS 2015 RTM

VS 2015 Update 2’s STL is C++17-so-far Feature Complete

Visual Studio 2015 Update 3

STL Fixes In VS 2015 Update 3

Getting permission denied (public key) on gitlab

Steps to be done, got same error but i fixed it. Gitlab wants ssh-rsa so below is the code to run ssh for rsa

ssh-keygen -o -t rsa -b 4096 -C "[email protected]"

[email protected] is your gitlab account email

It will prompt you to enter so just hit Enter after the below code is prompt,

Enter file in which to save the key (/home/yourDesktopName/.ssh/id_rsa):
It will prompt again you to enter so just hit Enter after the below code is prompt,

Enter passphrase (empty for no passphrase):
It will prompt again for the last you to enter so just hit Enter after the below code is prompt,

Enter same passphrase again:
You will show your ssh-rsa generate.
Login to your Gitlab account and Go to the right navbar you will get setting and in the left sidebar you will get ssh key. Enter in it.
Look above the prompt asking you to enter, you will get the path of ssh-rsa.
Go to your SSH folder and get the id_rsa.pub
Open it and get the key and Copy Paste to the Gitlab and you are nearly to done.
Check by: ssh -T [email protected]
You will get: Welcome to GitLab, @joy4!
Done.

Chrome desktop notification example

See also ServiceWorkerRegistration.showNotification

It appears that window.webkitNotifications has already been deprecated and removed. However, there's a new API, and it appears to work in the latest version of Firefox as well.

function notifyMe() {
  // Let's check if the browser supports notifications
  if (!("Notification" in window)) {
    alert("This browser does not support desktop notification");
  }

  // Let's check if the user is okay to get some notification
  else if (Notification.permission === "granted") {
    // If it's okay let's create a notification
    var notification = new Notification("Hi there!");
  }

  // Otherwise, we need to ask the user for permission
  // Note, Chrome does not implement the permission static property
  // So we have to check for NOT 'denied' instead of 'default'
  else if (Notification.permission !== 'denied') {
    Notification.requestPermission(function (permission) {

      // Whatever the user answers, we make sure we store the information
      if(!('permission' in Notification)) {
        Notification.permission = permission;
      }

      // If the user is okay, let's create a notification
      if (permission === "granted") {
        var notification = new Notification("Hi there!");
      }
    });
  } else {
    alert(`Permission is ${Notification.permission}`);
  }
}

codepen

HashSet vs. List performance

The answer, as always, is "It depends". I assume from the tags you're talking about C#.

Your best bet is to determine

A Set of data
Usage requirements

and write some test cases.

It also depends on how you sort the list (if it's sorted at all), what kind of comparisons need to be made, how long the "Compare" operation takes for the particular object in the list, or even how you intend to use the collection.

Generally, the best one to choose isn't so much based on the size of data you're working with, but rather how you intend to access it. Do you have each piece of data associated with a particular string, or other data? A hash based collection would probably be best. Is the order of the data you're storing important, or are you going to need to access all of the data at the same time? A regular list may be better then.

Additional:

Of course, my above comments assume 'performance' means data access. Something else to consider: what are you looking for when you say "performance"? Is performance individual value look up? Is it management of large (10000, 100000 or more) value sets? Is it the performance of filling the data structure with data? Removing data? Accessing individual bits of data? Replacing values? Iterating over the values? Memory usage? Data copying speed? For example, If you access data by a string value, but your main performance requirement is minimal memory usage, you might have conflicting design issues.

How to install MinGW-w64 and MSYS2?

MSYS has not been updated a long time, MSYS2 is more active, you can download from MSYS2, it has both mingw and cygwin fork package.

To install the MinGW-w64 toolchain (Reference):

Open MSYS2 shell from start menu
Run pacman -Sy pacman to update the package database
Re-open the shell, run pacman -Syu to update the package database and core system packages
Re-open the shell, run pacman -Su to update the rest
Install compiler:
- For 32-bit target, run pacman -S mingw-w64-i686-toolchain
- For 64-bit target, run pacman -S mingw-w64-x86_64-toolchain
Select which package to install, default is all
You may also need make, run pacman -S make

How to resolve git status "Unmerged paths:"?

All you should need to do is:

# if the file in the right place isn't already committed:
git add <path to desired file>

# remove the "both deleted" file from the index:
git rm --cached ../public/images/originals/dog.ai

# commit the merge:
git commit

How to extract public key using OpenSSL?

For those interested in the details - you can see what's inside the public key file (generated as explained above), by doing this:-

openssl rsa -noout -text -inform PEM -in key.pub -pubin

or for the private key file, this:-

openssl rsa -noout -text -in key.private

which outputs as text on the console the actual components of the key (modulus, exponents, primes, ...)

Can't get ScriptManager.RegisterStartupScript in WebControl nested in UpdatePanel to work

I had an issue with Page.ClientScript.RegisterStartUpScript - I wasn't using an update panel, but the control was cached. This meant that I had to insert the script into a Literal (or could use a PlaceHolder) so when rendered from the cache the script is included.

A similar solution might work for you.

How to form a correct MySQL connection string?

string MyConString = "Data Source='mysql7.000webhost.com';" +
"Port=3306;" +
"Database='a455555_test';" +
"UID='a455555_me';" +
"PWD='something';";

Laravel 4 Eloquent Query Using WHERE with OR AND OR?

Another way without using Modal

Database: stocks Columns:id,name,company_name,exchange_name,status

  $name ='aa'
  $stocks = DB::table('stocks')
            ->select('name', 'company_name', 'exchange_name')
            ->where(function($query) use ($name) {
                $query->where('name', 'like', '%' . $name . '%')
                ->orWhere('company_name', 'like', '%' . $name . '%');
            })
            ->Where('status', '=', 1)
            ->limit(20)
            ->get();

Automatic creation date for Django model form objects?

You can use the auto_now and auto_now_add options for updated_at and created_at respectively.

class MyModel(models.Model):
    created_at = models.DateTimeField(auto_now_add=True)
    updated_at = models.DateTimeField(auto_now=True)

Why does Python code use len() function instead of a length method?

It doesn't?

>>> "abc".__len__()
3

no match for ‘operator<<’ in ‘std::operator

There's only one error:

cout.cpp:26:29: error: no match for ‘operator<<’ in ‘std::operator<< [with _Traits = std::char_traits]((* & std::cout), ((const char*)"my structure ")) << m’

This means that the compiler couldn't find a matching overload for operator<<. The rest of the output is the compiler listing operator<< overloads that didn't match. The third line actually says this:

cout.cpp:26:29: note: candidates are:

DB2 Date format

One more solution REPLACE (CHAR(current date, ISO),'-','')

OS X Terminal Colors

Here is a solution I've found to enable the global terminal colors.

Edit your .bash_profile (since OS X 10.8) — or (for 10.7 and earlier): .profile or .bashrc or /etc/profile (depending on availability) — in your home directory and add following code:

export CLICOLOR=1
export LSCOLORS=GxFxCxDxBxegedabagaced

CLICOLOR=1 simply enables coloring of your terminal.

LSCOLORS=... specifies how to color specific items.

After editing .bash_profile, start a Terminal and force the changes to take place by executing:

source ~/.bash_profile

Then go to Terminal > Preferences, click on the Profiles tab and then the Text subtab and check Display ANSI Colors.

Verified on Sierra (May 2017).

Algorithm to generate all possible permutations of a list?

Bourne shell solution - in a total of four lines (without test for no param case):

test $# -eq 1 && echo "$1" && exit
for i in $*; do
  $0 `echo "$*" | sed -e "s/$i//"` | sed -e "s/^/$i /"
done

Hide keyboard in react-native

For hide keyboard use Keyboard.dismiss() inside TextInput.

Popup Message boxes

Use the following library: import javax.swing.JOptionPane;

Input at the top of the code-line. You must only add this, because the other things is done correctly!

How to implement a Keyword Search in MySQL?

Personally, I wouldn't use the LIKE string comparison on the ID field or any other numeric field. It doesn't make sense for a search for ID# "216" to return 16216, 21651, 3216087, 5321668..., and so on and so forth; likewise with salary.

Also, if you want to use prepared statements to prevent SQL injections, you would use a query string like:

SELECT * FROM job WHERE `position` LIKE CONCAT('%', ? ,'%') OR ...

Copy table from one database to another

If migrating constantly between two databases, then insert into an already existing table structure is a possibility. If so, then:

Use the following syntax:

insert into DESTINATION_DB.dbo.destination_table
select *
  from SOURCE_DB.dbo.source_table
[where x ...]

If migrating a LOT of tables (or tables with foreign keys constraints) I'd recommend:

Generating Scripts with the Advanced option / Types of data to script : Data only OR
Resort using a third party tool.

Hope it helps!

VB.net Need Text Box to Only Accept Numbers

You must first validate if the input is actually an integer. You can do it with Integer.TryParse:

Dim intValue As Integer
If Integer.TryParse(TxtBox.Text, intValue) AndAlso intValue > 0 AndAlso intValue < 11 Then
    MessageBox.Show("Thank You, your rating was " & TxtBox.Text)
Else
    MessageBox.Show("Please Enter a Number from 1 to 10")
End If

How to declare global variables in Android?

Create this subclass

public class MyApp extends Application {
  String foo;
}

In the AndroidManifest.xml add android:name

Example

<application android:name=".MyApp" 
       android:icon="@drawable/icon" 
       android:label="@string/app_name">

Grant Select on all Tables Owned By Specific User

Well, it's not a single statement, but it's about as close as you can get with oracle:

BEGIN
   FOR R IN (SELECT owner, table_name FROM all_tables WHERE owner='TheOwner') LOOP
      EXECUTE IMMEDIATE 'grant select on '||R.owner||'.'||R.table_name||' to TheUser';
   END LOOP;
END;

Access to build environment variables from a groovy script in a Jenkins build step (Windows)

The only way I could get this to work (on Linux) was to follow this advice:

https://wiki.jenkins-ci.org/display/JENKINS/Parameterized+System+Groovy+script

import hudson.model.*

// get current thread / Executor and current build
def thr = Thread.currentThread()
def build = thr?.executable

// if you want the parameter by name ...
def hardcoded_param = "FOOBAR"
def resolver = build.buildVariableResolver
def hardcoded_param_value = resolver.resolve(hardcoded_param)

println "param ${hardcoded_param} value : ${hardcoded_param_value}"

This is on Jenkins 1.624 running on CentOS 6.7

Command copy exited with code 4 when building - Visual Studio restart solves it

In case the post build event contains copy/xcopy command for copying build output to some directory(which usually is the most common post build operation) the problem can occur in case the full directory path either of source or target destinations contain folder names which include spaces. Remove space for the directory name(s) and try.

How to make an element width: 100% minus padding?

Here is the recommendation from codeontrack.com, which has good solution examples:

Instead of setting the width of the div to 100%, set it to auto, and be sure, that the <div> is set to display: block (default for <div>).

How do I print out the contents of an object in Rails for easy debugging?

.inspect is what you're looking for, it's way easier IMO than .to_yaml!

user = User.new
user.name = "will"
user.email = "[email protected]"

user.inspect
#<name: "will", email: "[email protected]">

How do I print a list of "Build Settings" in Xcode project?

In case you would like to read/check your Target Build Settings in runtime using code, here is the way:

1) Add a Run Script:

cp ${PROJECT_FILE_PATH}/project.pbxproj ${CONFIGURATION_BUILD_DIR}/${EXECUTABLE_NAME}.app/BuildSetting.pbxproj

It will copy the Target Build Settings file into your Main Bundle (will be called BuildSetting.pbxproj).

2) You can now check the contents of that file at any time in code:

NSString *thePathString = [[NSBundle mainBundle] pathForResource:@"BuildSetting" ofType:@"pbxproj"];
NSDictionary *theDictionary = [NSDictionary dictionaryWithContentsOfFile:thePathString];

"Fatal error: Cannot redeclare <function>"

I want to add my 2 cent experience that might be helpful for many of you.

If you declare a function inside a loop (for, foreach, while), you will face this error message.

How do you cache an image in Javascript

Nowdays, there is a new technique suggested by google to cache and improve your image rendering process:

Include the JavaScript Lazysizes file: lazysizes.js
Add the file to the html file you want to use in: <script src="lazysizes.min.js" async></script>
Add the lazyload class to your image: <img data-src="images/flower3.png" class="lazyload" alt="">

Getting Index of an item in an arraylist;

Basically you need to look up ArrayList element based on name getName. Two approaches to this problem:

1- Don't use ArrayList, Use HashMap<String,AutionItem> where String would be name

2- Use getName to generate index and use index based addition into array list list.add(int index, E element). One way to generate index from name would be to use its hashCode and modulo by ArrayList current size (something similar what is used inside HashMap)

Make div fill remaining space along the main axis in flexbox

Use the flex-grow property to make a flex item consume free space on the main axis.

This property will expand the item as much as possible, adjusting the length to dynamic environments, such as screen re-sizing or the addition / removal of other items.

A common example is flex-grow: 1 or, using the shorthand property, flex: 1.

Hence, instead of width: 96% on your div, use flex: 1.

You wrote:

So at the moment, it's set to 96% which looks OK until you really squash the screen - then the right hand div gets a bit starved of the space it needs.

The squashing of the fixed-width div is related to another flex property: flex-shrink

By default, flex items are set to flex-shrink: 1 which enables them to shrink in order to prevent overflow of the container.

To disable this feature use flex-shrink: 0.

For more details see The flex-shrink factor section in the answer here:

What are the differences between flex-basis and width?

Learn more about flex alignment along the main axis here:

In CSS Flexbox, why are there no "justify-items" and "justify-self" properties?

Learn more about flex alignment along the cross axis here:

How does flex-wrap work with align-self, align-items and align-content?

Difference between ref and out parameters in .NET

out has gotten a new more succint syntax in C#7 https://docs.microsoft.com/en-us/dotnet/articles/csharp/whats-new/csharp-7#more-expression-bodied-members and even more exciting is the C#7 tuple enhancements that are a more elegant choice than using ref and out IMHO.

Endless loop in C/C++

The idiom designed into the C language (and inherited into C++) for infinite looping is for(;;): the omission of a test form. The do/while and while loops do not have this special feature; their test expressions are mandatory.

for(;;) does not express "loop while some condition is true that happens to always be true". It expresses "loop endlessly". No superfluous condition is present.

Therefore, the for(;;) construct is the canonical endless loop. This is a fact.

All that is left to opinion is whether or not to write the canonical endless loop, or to choose something baroque which involves extra identifiers and constants, to build a superfluous expression.

Even if the test expression of while were optional, which it isn't, while(); would be strange. while what? By contrast, the answer to the question for what? is: why, ever---for ever! As a joke some programmers of days past have defined blank macros, so they could write for(ev;e;r);.

while(true) is superior to while(1) because at least it doesn't involve the kludge that 1 represents truth. However, while(true) didn't enter into C until C99. for(;;) exists in every version of C going back to the language described in the 1978 book K&R1, and in every dialect of C++, and even related languages. If you're coding in a code base written in C90, you have to define your own true for while (true).

while(true) reads badly. While what is true? We don't really want to see the identifier true in code, except when we are initializing boolean variables or assigning to them. true need not ever appear in conditional tests. Good coding style avoids cruft like this:

if (condition == true) ...

in favor of:

if (condition) ...

For this reason while (0 == 0) is superior to while (true): it uses an actual condition that tests something, which turns into a sentence: "loop while zero is equal to zero." We need a predicate to go nicely with "while"; the word "true" isn't a predicate, but the relational operator == is.

How do I pass multiple attributes into an Angular.js attribute directive?

You do it exactly the same way as you would with an element directive. You will have them in the attrs object, my sample has them two-way binding via the isolate scope but that's not required. If you're using an isolated scope you can access the attributes with scope.$eval(attrs.sample) or simply scope.sample, but they may not be defined at linking depending on your situation.

app.directive('sample', function () {
    return {
        restrict: 'A',
        scope: {
            'sample' : '=',
            'another' : '='
        },
        link: function (scope, element, attrs) {
            console.log(attrs);
            scope.$watch('sample', function (newVal) {
                console.log('sample', newVal);
            });
            scope.$watch('another', function (newVal) {
                console.log('another', newVal);
            });
        }
    };
});

used as:

<input type="text" ng-model="name" placeholder="Enter a name here">
<input type="text" ng-model="something" placeholder="Enter something here">
<div sample="name" another="something"></div>

How do I determine if my python shell is executing in 32bit or 64bit?

When starting the Python interpreter in the terminal/command line you may also see a line like:

Python 2.7.2 (default, Jun 12 2011, 14:24:46) [MSC v.1500 64 bit (AMD64)] on win32

Where [MSC v.1500 64 bit (AMD64)] means 64-bit Python. Works for my particular setup.

What does the keyword "transient" mean in Java?

Google is your friend - first hit - also you might first have a look at what serialization is.

It marks a member variable not to be serialized when it is persisted to streams of bytes. When an object is transferred through the network, the object needs to be 'serialized'. Serialization converts the object state to serial bytes. Those bytes are sent over the network and the object is recreated from those bytes. Member variables marked by the java transient keyword are not transferred, they are lost intentionally.

Example from there, slightly modified (thanks @pgras):

public class Foo implements Serializable
 {
   private String saveMe;
   private transient String dontSaveMe;
   private transient String password;
   //...
 }

SQL Plus change current directory

I don't think that you can change the directory in SQL*Plus.

Instead of changing directory, you can use @@filename, which reads in another script whose location is relative to the directory the current script is running in. For example, if you have two scripts

C:\Foo\Bar\script1.sql
C:\Foo\Bar\Baz\script2.sql

then script1.sql can run script2.sql if it contains the line

@@Baz\script2.sql

See this for more info about @@.

Regular expression to match exact number of characters?

What you have is correct, but this is more consice:

^[A-Z]{3}$

How do I specify the platform for MSBuild?

When you define different build configurations in your visual studio solution for your projects using a tool like ConfigurationTransform, you may want your Teamcity build, to build you a specified build configuration. You may have build configurations e.g., Debug, Release, Dev, UAT, Prod etc defined. This means, you will have MSBuild Configuration transformation setup for the different configurations. These different configurations are usually used when you have different configurations, e.g. different database connection strings, for the different environment. This is very common because you would have a different database for your production environment from your playground development environment.

They say a picture is worth a thousand words, please see the image below how you would specify multiple build configurations in Teamcity.

In the commandline input text box, specify as below

/p:OutputPath=Publish;Configuration=Dev

Here, I have specified two commandline build configurations/arguments OutputPath and build Configuration with values Publish and Dev respectively, but it could have been, UAT or Prod configuration. If you want more, simply separate them by semi-colon,;

Automatically plot different colored lines

Actually, a decent shortcut method for getting the colors to cycle is to use hold all; in place of hold on;. Each successive plot will rotate (automatically for you) through MATLAB's default colormap.

From the MATLAB site on hold:

hold all holds the plot and the current line color and line style so that subsequent plotting commands do not reset the ColorOrder and LineStyleOrder property values to the beginning of the list. Plotting commands continue cycling through the predefined colors and linestyles from where the last plot stopped in the list.

Embed Google Map code in HTML with marker

USE this , Don't forget to get a google api key from

https://console.developers.google.com/apis/credentials

and replace it

    <div id="map" style="width:100%;height:400px;"></div>

<script>
function myMap() {

var map = new google.maps.Map(document.getElementById("map"), mapOptions);
  var myCenter = new google.maps.LatLng(38.224905, 48.252143);
  var mapCanvas = document.getElementById("map");
  var mapOptions = {center: myCenter, zoom: 16};
  var map = new google.maps.Map(mapCanvas, mapOptions);
  var marker = new google.maps.Marker({position:myCenter});
  marker.setMap(map);
}
</script>

<script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&callback=myMap"></script>

Typescript: No index signature with a parameter of type 'string' was found on type '{ "A": string; }

You can fix the errors by validating your input, which is something you should do regardless of course.

The following typechecks correctly, via type guarding validations

const DNATranscriber = {
    G: 'C',
    C: 'G',
    T: 'A',
    A: 'U'
};

export default class Transcriptor {
    toRna(dna: string) {
        const codons = [...dna];
        if (!isValidSequence(codons)) {
            throw Error('invalid sequence');
        }
        const transcribedRNA = codons.map(codon => DNATranscriber[codon]);
        return transcribedRNA;
    }
}

function isValidSequence(values: string[]): values is Array<keyof typeof DNATranscriber> {
    return values.every(isValidCodon);
}
function isValidCodon(value: string): value is keyof typeof DNATranscriber {
    return value in DNATranscriber;
}

It is worth mentioning that you seem to be under the misapprehention that converting JavaScript to TypeScript involves using classes.

In the following, more idiomatic version, we leverage TypeScript to improve clarity and gain stronger typing of base pair mappings without changing the implementation. We use a function, just like the original, because it makes sense. This is important! Converting JavaScript to TypeScript has nothing to do with classes, it has to do with static types.

const DNATranscriber = {
    G = 'C',
    C = 'G',
    T = 'A',
    A = 'U'
};

export default function toRna(dna: string) {
    const codons = [...dna];
    if (!isValidSequence(codons)) {
        throw Error('invalid sequence');
    }
    const transcribedRNA = codons.map(codon => DNATranscriber[codon]);
    return transcribedRNA;
}

function isValidSequence(values: string[]): values is Array<keyof typeof DNATranscriber> {
    return values.every(isValidCodon);
}
function isValidCodon(value: string): value is keyof typeof DNATranscriber {
    return value in DNATranscriber;
}

Update:

Since TypeScript 3.7, we can write this more expressively, formalizing the correspondence between input validation and its type implication using assertion signatures.

const DNATranscriber = {
    G = 'C',
    C = 'G',
    T = 'A',
    A = 'U'
} as const;

type DNACodon = keyof typeof DNATranscriber;
type RNACodon = typeof DNATranscriber[DNACodon];

export default function toRna(dna: string): RNACodon[] {
    const codons = [...dna];
    validateSequence(codons);
    const transcribedRNA = codons.map(codon => DNATranscriber[codon]);
    return transcribedRNA;
}

function validateSequence(values: string[]): asserts values is DNACodon[] {
    if (!values.every(isValidCodon)) {
        throw Error('invalid sequence');    
    }
}
function isValidCodon(value: string): value is DNACodon {
    return value in DNATranscriber;
}

You can read more about assertion signatures in the TypeScript 3.7 release notes.

How can I symlink a file in Linux?

How to create symlink in vagrant. Steps:

In vagrant file create a synced folder. e.g config.vm.synced_folder "F:/Sunburst/source/sunburst/lms", "/source" F:/Sunburst/source/sunburst/lms :- where the source code, /source :- directory path inside the vagrant
Vagrant up and type vagrant ssh and go to source directory e.g cd source
Verify your source code folder structure is available in the source directory. e.g /source/local
Then go to the guest machine directory where the files which are associate with the browser. After get backup of the file. e.g sudo mv local local_bk
Then create symlink e.g sudo ln -s /source/local local. local mean link-name (folder name in guest machine which you are going to link) if you need to remove the symlink :- Type sudo rm local

Difference between applicationContext.xml and spring-servlet.xml in Spring Framework

In simple words,

applicationContext.xml defines the beans that are shared among all the servlets. If your application have more than one servlet, then defining the common resources in the applicationContext.xml would make more sense.

spring-servlet.xml defines the beans that are related only to that servlet. Here it is the dispatcher servlet. So, your Spring MVC controllers must be defined in this file.

There is nothing wrong in defining all the beans in the spring-servlet.xml if you are running only one servlet in your web application.

How to create an 2D ArrayList in java?

I want to create a 2D array that each cell is an ArrayList!

If you want to create a 2D array of ArrayList.Then you can do this :

ArrayList[][] table = new ArrayList[10][10];
table[0][0] = new ArrayList(); // add another ArrayList object to [0,0]
table[0][0].add(); // add object to that ArrayList

What is the MySQL JDBC driver connection string?

"jdbc:mysql://localhost"

From the oracle docs..

jdbc:mysql://[host][,failoverhost...]
[:port]/[database]
[?propertyName1][=propertyValue1]
[&propertyName2][=propertyValue2]

host:port is the host name and port number of the computer hosting your database. If not specified, the default values of host and port are 127.0.0.1 and 3306, respectively.

database is the name of the database to connect to. If not specified, a connection is made with no default database.

failover is the name of a standby database (MySQL Connector/J supports failover).

propertyName=propertyValue represents an optional, ampersand-separated list of properties. These attributes enable you to instruct MySQL Connector/J to perform various tasks.

Does Spring @Transactional attribute work on a private method?

The Question is not private or public, the question is: How is it invoked and which AOP implementation you use!

If you use (default) Spring Proxy AOP, then all AOP functionality provided by Spring (like @Transactional) will only be taken into account if the call goes through the proxy. -- This is normally the case if the annotated method is invoked from another bean.

This has two implications:

Because private methods must not be invoked from another bean (the exception is reflection), their @Transactional Annotation is not taken into account.
If the method is public, but it is invoked from the same bean, it will not be taken into account either (this statement is only correct if (default) Spring Proxy AOP is used).

@See Spring Reference: Chapter 9.6 9.6 Proxying mechanisms

IMHO you should use the aspectJ mode, instead of the Spring Proxies, that will overcome the problem. And the AspectJ Transactional Aspects are woven even into private methods (checked for Spring 3.0).

What is the Python equivalent for a case/switch statement?

The direct replacement is if/elif/else.

However, in many cases there are better ways to do it in Python. See "Replacements for switch statement in Python?".

state machines tutorials

State machines are not something that inherently needs a tutorial to be explained or even used. What I suggest is that you take a look at the data and how it needs to be parsed.

For example, I had to parse the data protocol for a Near Space balloon flight computer, it stored data on the SD card in a specific format (binary) which needed to be parsed out into a comma seperated file. Using a state machine for this makes the most sense because depending on what the next bit of information is we need to change what we are parsing.

The code is written using C++, and is available as ParseFCU. As you can see, it first detects what version we are parsing, and from there it enters two different state machines.

It enters the state machine in a known-good state, at that point we start parsing and depending on what characters we encounter we either move on to the next state, or go back to a previous state. This basically allows the code to self-adapt to the way the data is stored and whether or not certain data exists at all even.

In my example, the GPS string is not a requirement for the flight computer to log, so processing of the GPS string may be skipped over if the ending bytes for that single log write is found.

State machines are simple to write, and in general I follow the rule that it should flow. Input going through the system should flow with certain ease from state to state.

Java time-based map/cache with expiring keys

If anybody needs a simple thing, following is a simple key-expiring set. It might be converted to a map easily.

public class CacheSet<K> {
    public static final int TIME_OUT = 86400 * 1000;

    LinkedHashMap<K, Hit> linkedHashMap = new LinkedHashMap<K, Hit>() {
        @Override
        protected boolean removeEldestEntry(Map.Entry<K, Hit> eldest) {
            final long time = System.currentTimeMillis();
            if( time - eldest.getValue().time > TIME_OUT) {
                Iterator<Hit> i = values().iterator();

                i.next();
                do {
                    i.remove();
                } while( i.hasNext() && time - i.next().time > TIME_OUT );
            }
            return false;
        }
    };


    public boolean putIfNotExists(K key) {
        Hit value = linkedHashMap.get(key);
        if( value != null ) {
            return false;
        }

        linkedHashMap.put(key, new Hit());
        return true;
    }

    private static class Hit {
        final long time;


        Hit() {
            this.time = System.currentTimeMillis();
        }
    }
}

Configuring RollingFileAppender in log4j

Faced more issues while making this work. Here are the details:

To download and add apache-log4j-extras-1.1.jar in the classpath, didn't notice this at first.
The RollingFileAppender should be org.apache.log4j.rolling.RollingFileAppender instead of org.apache.log4j.RollingFileAppender. This can give the error: log4j:ERROR No output stream or file set for the appender named [file].
We had to upgrade the log4j library from log4j-1.2.14.jar to log4j-1.2.16.jar.

Below is the appender configuration which worked for me:

<appender name="file" class="org.apache.log4j.rolling.RollingFileAppender">
        <param name="threshold" value="debug" />
        <rollingPolicy name="file"
            class="org.apache.log4j.rolling.TimeBasedRollingPolicy">
            <param name="FileNamePattern" value="logs/MyLog-%d{yyyy-MM-dd-HH-mm}.log.gz" />
            <!-- The below param will keep the live update file in a different location-->
            <!-- param name="ActiveFileName" value="current/MyLog.log" /-->
        </rollingPolicy>

        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%5p %d{ISO8601} [%t][%x] %c - %m%n" />
        </layout>
</appender>

Set adb vendor keys

I had the same problem running Ubuntu 18.04. I tried multiple solutions but my device (OnePlus 5T) was always unauthorized.

Solution

Configure udev rules on Ubuntu. To do this, just follow the official documentation: https://developer.android.com/studio/run/device

The idVendor of my device (OnePlus) is not listed. To get it, just connect your device and use lsusb:

Bus 003 Device 008: ID 2a70:4ee7

In this example, 2a70 is the idVendor.
Remove existing adb keys on Ubuntu:

rm -v ~/.android/adbkey* ~/.android/adbkey ~/.android/adbkey.pub
'Revoke USB debugging authorizations' on your device configuration (developer options).
Finally, restart the adb server to create a new key:

sudo adb kill-server sudo adb devices

After that, I got the authorization prompt on my device and I authorized it.

Current user in Magento?

$customer = Mage::getSingleton('customer/session')->getCustomer();
    $customerAddressId = Mage::getSingleton('customer/session')->getCustomer()->getDefaultBilling();
    $address = Mage::getModel('customer/address')->load($customerAddressId);
    $fullname = $customer->getName();
    $firstname = $customer->getFirstname();
    $lastname = $customer->getLastname();
    $email = $customer->getEmail();
    $taxvat = $customer->getTaxvat();
    $tele = $customer->getTelephone();
    $telephone = $address->getTelephone();
    $street = $address->getStreet();
    $City = $address->getCity();
    $region = $address->getRegion();
    $postcode = $address->getPostcode();

Get customer Default Billing address

Dropping a connected user from an Oracle 10g database schema

To find the sessions, as a DBA use

select sid,serial# from v$session where username = '<your_schema>'

If you want to be sure only to get the sessions that use SQL Developer, you can add and program = 'SQL Developer'. If you only want to kill sessions belonging to a specific developer, you can add a restriction on os_user

Then kill them with

alter system kill session '<sid>,<serial#>'

(e.g. alter system kill session '39,1232')

A query that produces ready-built kill-statements could be

select 'alter system kill session ''' || sid || ',' || serial# || ''';' from v$session where username = '<your_schema>'

This will return one kill statement per session for that user - something like:

alter system kill session '375,64855';

alter system kill session '346,53146';

Create a shortcut on Desktop

private void CreateShortcut(string executablePath, string name)
    {
        CMDexec("echo Set oWS = WScript.CreateObject('WScript.Shell') > CreateShortcut.vbs");
        CMDexec("echo sLinkFile = '" + Environment.GetEnvironmentVariable("homedrive") + "\\users\\" + Environment.GetEnvironmentVariable("username") + "\\desktop\\" + name + ".ink' >> CreateShortcut.vbs");
        CMDexec("echo Set oLink = oWS.CreateShortcut(sLinkFile) >> CreateShortcut.vbs");
        CMDexec("echo oLink.TargetPath = '" + executablePath + "' >> CreateShortcut.vbs");
        CMDexec("echo oLink.Save >> CreateShortcut.vbs");
        CMDexec("cscript CreateShortcut.vbs");
        CMDexec("del CreateShortcut.vbs");
    }

What does a (+) sign mean in an Oracle SQL WHERE clause?

This is an Oracle-specific notation for an outer join. It means that it will include all rows from t1, and use NULLS in the t0 columns if there is no corresponding row in t0.

In standard SQL one would write:

SELECT t0.foo, t1.bar
  FROM FIRST_TABLE t0
 RIGHT OUTER JOIN SECOND_TABLE t1;

Oracle recommends not to use those joins anymore if your version supports ANSI joins (LEFT/RIGHT JOIN) :

Oracle recommends that you use the FROM clause OUTER JOIN syntax rather than the Oracle join operator. Outer join queries that use the Oracle join operator (+) are subject to the following rules and restrictions […]

LIKE operator in LINQ

List<Categories> categoriess;
        private void Buscar()
        {
            try
            {
                categoriess = Contexto.Categories.ToList();
                categoriess = categoriess.Where(n => n.CategoryID >= Convert.ToInt32(txtCatID.Text) && n.CategoryID <= Convert.ToInt32(txtCatID1.Text) && (n.CategoryName.Contains(txtCatName.Text)) ).ToList();

Using "If cell contains" in VBA excel

Requirement:
Find a cell containing the word TOTAL then to enter a dash in the cell below it.

Solution: This solution uses the Find method of the Range object, as it seems appropriate to use it rather than brute force (For…Next loop). For explanation and details about the method see Range.Find method (Excel)

Implementation:
In order to provide flexibility the Find method is wrapped in this function:

Function Range_ƒFind_Action(sWhat As String, rTrg As Range) As Boolean

Where:
sWhat: contains the string to search for
rTrg: is the range to be searched

The function returns True if any match is found, otherwise it returns False

Additionally, every time the function finds a match it passes the resulting range to the procedure Range_Find_Action to execute the required action, (i.e. "enter a dash in the cell below it"). The "required action" is in a separated procedure to allow for customization and flexibility.

This is how the function is called:

This test is searching for "total" to show the effect of the MatchCase:=False. The match can be made case sensitive by changing it to MatchCase:=True

Sub Range_Find_Action_TEST()
Dim sWhat As String, rTrg As Range
Dim sMsgbdy As String
    sWhat = "total"                                             'String to search for (update as required)
    Rem Set rTrg = ThisWorkbook.Worksheets("Sht(0)").UsedRange  'Range to Search (use this to search all used cells)
    Set rTrg = ThisWorkbook.Worksheets("Sht(0)").Rows(6)        'Range to Search (update as required)
    sMsgbdy = IIf(Range_ƒFind_Action(sWhat, rTrg), _
        "Cells found were updated successfully", _
        "No cells were found.")
    MsgBox sMsgbdy, vbInformation, "Range_ƒFind_Action"
    End Sub

This is the Find function

Function Range_ƒFind_Action(sWhat As String, rTrg As Range) As Boolean
Dim rCll As Range, s1st As String
    With rTrg

        Rem Set First Cell Found
        Set rCll = .Find(What:=sWhat, After:=.Cells(1), _
            LookIn:=xlFormulas, LookAt:=xlPart, _
            SearchOrder:=xlByRows, SearchDirection:=xlNext, _
            MatchCase:=False, SearchFormat:=False)

        Rem Validate First Cell
        If rCll Is Nothing Then Exit Function
        s1st = rCll.Address

        Rem Perform Action
        Call Range_Find_Action(rCll)

        Do
            Rem Find Other Cells
            Set rCll = .FindNext(After:=rCll)
            Rem Validate Cell vs 1st Cell
            If rCll.Address <> s1st Then Call Range_Find_Action(rCll)

        Loop Until rCll.Address = s1st

    End With

    Rem Set Results
    Range_ƒFind_Action = True

    End Function

This is the Action procedure

Sub Range_Find_Action(rCll)
    rCll.Offset(1).Value2 = Chr(167)    'Update as required - Using `§` instead of "-" for visibilty purposes
    End Sub

How do I convert a single character into it's hex ascii value in python

This might help

import binascii

x = b'test'
x = binascii.hexlify(x)
y = str(x,'ascii')

print(x) # Outputs b'74657374' (hex encoding of "test")
print(y) # Outputs 74657374

x_unhexed = binascii.unhexlify(x)
print(x_unhexed) # Outputs b'test'

x_ascii = str(x_unhexed,'ascii')
print(x_ascii) # Outputs test

This code contains examples for converting ASCII characters to and from hexadecimal. In your situation, the line you'd want to use is str(binascii.hexlify(c),'ascii').

Why isn't my Pandas 'apply' function referencing multiple columns working?

If you just want to compute (column a) % (column b), you don't need apply, just do it directly:

In [7]: df['a'] % df['c']                                                                                                                                                        
Out[7]: 
0   -1.132022                                                                                                                                                                    
1   -0.939493                                                                                                                                                                    
2    0.201931                                                                                                                                                                    
3    0.511374                                                                                                                                                                    
4   -0.694647                                                                                                                                                                    
5   -0.023486                                                                                                                                                                    
Name: a

C# 4.0: Convert pdf to byte[] and vice versa

Easiest way:

byte[] buffer;
using (Stream stream = new IO.FileStream("file.pdf"))
{
   buffer = new byte[stream.Length - 1];
   stream.Read(buffer, 0, buffer.Length);
}

using (Stream stream = new IO.FileStream("newFile.pdf"))
{
   stream.Write(buffer, 0, buffer.Length);
}

Or something along these lines...

How to set image in circle in swift

Based in the answer of @DanielQ

Swift 4 and Swift 3

import UIKit

extension UIImageView {

    func setRounded() {
        self.layer.cornerRadius = (self.frame.width / 2) //instead of let radius = CGRectGetWidth(self.frame) / 2
        self.layer.masksToBounds = true
    }
}

You can use it in any ViewController with:

imageView.setRounded()

Kill detached screen session

For me a simple

exit

works. This is from within the screen session.

What does the question mark operator mean in Ruby?

Also note ? along with a character, will return the ASCII character code for A

For example:

?F # => will return 70

Alternately in ruby 1.8 you can do:

"F"[0]

or in ruby 1.9:

"F".ord

Also notice that ?F will return the string "F", so in order to make the code shorter, you can also use ?F.ord in Ruby 1.9 to get the same result as "F".ord.

Rename Pandas DataFrame Index

You can also use Index.set_names as follows:

In [25]: x = pd.DataFrame({'year':[1,1,1,1,2,2,2,2],
   ....:                   'country':['A','A','B','B','A','A','B','B'],
   ....:                   'prod':[1,2,1,2,1,2,1,2],
   ....:                   'val':[10,20,15,25,20,30,25,35]})

In [26]: x = x.set_index(['year','country','prod']).squeeze()

In [27]: x
Out[27]: 
year  country  prod
1     A        1       10
               2       20
      B        1       15
               2       25
2     A        1       20
               2       30
      B        1       25
               2       35
Name: val, dtype: int64
In [28]: x.index = x.index.set_names('foo', level=1)

In [29]: x
Out[29]: 
year  foo  prod
1     A    1       10
           2       20
      B    1       15
           2       25
2     A    1       20
           2       30
      B    1       25
           2       35
Name: val, dtype: int64

Reference list item by index within Django template?

A better way: custom template filter: https://docs.djangoproject.com/en/dev/howto/custom-template-tags/

such as get my_list[x] in templates:

in template

{% load index %}
{{ my_list|index:x }}

templatetags/index.py

from django import template
register = template.Library()

@register.filter
def index(indexable, i):
    return indexable[i]

if my_list = [['a','b','c'], ['d','e','f']], you can use {{ my_list|index:x|index:y }} in template to get my_list[x][y]

It works fine with "for"

{{ my_list|index:forloop.counter0 }}

Tested and works well ^_^

Abstract Class:-Real Time Example

You should be able to cite at least one from the JDK itself. Look in the java.util.collections package. There are several abstract classes. You should fully understand interface, abstract, and concrete for Map and why Joshua Bloch wrote it that way.

How to solve Permission denied (publickey) error when using Git?

These are the steps I followed in windows 10

Open Git Bash.

Generate Public Key:

ssh-keygen -t rsa -b 4096 -C "[email protected]"

Copy generated key to the clipboard (works like CTRL+C)
```
clip < ~/.ssh/id_rsa.pub
```
Browser, go to Github => Profile=> Settings => SSH and GPG keys => Add Key
Provide the key name and paste clipboard (CTRL+V).
Finally, test your connection (Git bash)
```
ssh -T [email protected]
```

Thanks!

Inline style to act as :hover in CSS

If that <p> tag is created from JavaScript, then you do have another option: use JSS to programmatically insert stylesheets into the document head. It does support '&:hover'. https://cssinjs.org/

What is the convention in JSON for empty vs. null?

Empty array for empty collections and null for everything else.

Set today's date as default date in jQuery UI datepicker

You have not defined

$("#mydate").datepicker({});

How can I count occurrences with groupBy?

Here is example for list of Objects

Map<String, Long> requirementCountMap = requirements.stream().collect(Collectors.groupingBy(Requirement::getRequirementType, Collectors.counting()));

PhpMyAdmin "Wrong permissions on configuration file, should not be world writable!"

Just in case, someone out there having same issue but changing file permission doesn't solve the issue, add this line to your config.inc.php file

<?php
// other config goes here . . . 
$cfg['CheckConfigurationPermissions'] = false;

And you're good to go.

In my case, I'm using windows 10 WSL with phpmyadmin installed on D: drive. There's no way to (for now) change file permission on local disk through WSL unless your installation directory is inside WSL filesystem it-self. There's updates according to this issue, but still on insider build.

Cheers.

C# Connecting Through Proxy

This is easily achieved either programmatically, in your code, or declaratively in either the web.config or the app.config.

You can programmatically create a proxy like so:

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("[ultimate destination of your request]");
WebProxy myproxy = new WebProxy("[your proxy address]", [your proxy port number]);
myproxy.BypassProxyOnLocal = false;
request.Proxy = myproxy;
request.Method = "GET";
HttpWebResponse response = (HttpWebResponse) request.GetResponse();

You're basically assigning the WebProxy object to the request object's proxy property. This request will then use the proxy you define.

To achieve the same thing declaratively, you can do the following:

<system.net>
  <defaultProxy>
    <proxy
      proxyaddress="http://[your proxy address and port number]"
      bypassonlocal="false"
    />
  </defaultProxy>
</system.net>

within your web.config or app.config. This sets a default proxy that all http requests will use. Depending upon exactly what you need to achieve, you may or may not require some of the additional attributes of the defaultProxy / proxy element, so please refer to the documentation for those.

Converting std::__cxx11::string to std::string

Is it possible that you are using GCC 5?

If you get linker errors about undefined references to symbols that involve types in the std::__cxx11 namespace or the tag [abi:cxx11] then it probably indicates that you are trying to link together object files that were compiled with different values for the _GLIBCXX_USE_CXX11_ABI macro. This commonly happens when linking to a third-party library that was compiled with an older version of GCC. If the third-party library cannot be rebuilt with the new ABI then you will need to recompile your code with the old ABI.

Source: GCC 5 Release Notes/Dual ABI

Defining the following macro before including any standard library headers should fix your problem: #define _GLIBCXX_USE_CXX11_ABI 0

How to Increase Import Size Limit in phpMyAdmin

First you have to change values in php.ini file as per your requirements.

post_max_size = 1024M 
upload_max_filesize = 1024M 
max_execution_time = 3600
max_input_time = 3600 
memory_limit = 1024M

Note - Change these values carefully. These values will impact for all of your projects of that server.

Now, If above solutions are not working, kindly check your phpmyadmin.conf file. If you are using WAMP so you can find the file in "C:\wamp64\alias".

You have to change below values.

Values already in file are -

  php_admin_value upload_max_filesize 128M
  php_admin_value post_max_size 128M
  php_admin_value max_execution_time 360
  php_admin_value max_input_time 360

Change above code to -

#  php_admin_value upload_max_filesize 128M
#  php_admin_value post_max_size 128M
#  php_admin_value max_execution_time 360
#  php_admin_value max_input_time 360

Now just restart your server, to work with changed values. :)

Creating a new ArrayList in Java

Material please go through this Link And also try this

 ArrayList<Class> myArray= new ArrayList<Class>();

How to extract week number in sql

After converting your varchar2 date to a true date datatype, then convert back to varchar2 with the desired mask:

to_char(to_date('01/02/2012','MM/DD/YYYY'),'WW')

If you want the week number in a number datatype, you can wrap the statement in to_number():

to_number(to_char(to_date('01/02/2012','MM/DD/YYYY'),'WW'))

However, you have several week number options to consider:

WW  Week of year (1-53) where week 1 starts on the first day of the year and continues to the seventh day of the year.
W   Week of month (1-5) where week 1 starts on the first day of the month and ends on the seventh.
IW  Week of year (1-52 or 1-53) based on the ISO standard.

C# Parsing JSON array of objects

string jsonData1=@"[{""name"":""0"",""price"":""40"",""count"":""1"",""productId"":""4"",""catid"":""4"",""productTotal"":""40"",""orderstatus"":""0"",""orderkey"":""123456789""}]";

                  string jsonData = jsonData1.Replace("\"", "");


                  DataSet ds = new DataSet();
                  DataTable dt = new DataTable();
       JArray array= JArray.Parse(jsonData);

couldnot parse , if the vaule is a string..

look at name : meals , if name : 1 then it will parse

C++ Redefinition Header Files (winsock2.h)

As others suggested, the problem is when windows.h is included before WinSock2.h. Because windows.h includes winsock.h. You can not use both WinSock2.h and winsock.h.

Solutions:

Include WinSock2.h before windows.h. In the case of precompiled headers, you should solve it there. In the case of simple project, it is easy. However in big projects (especially when writing portable code, without precompiled headers) it can be very hard, because when your header with WinSock2.h is included, windows.h can be already included from some other header/implementation file.
Define WIN32_LEAN_AND_MEAN before windows.h or project wide. But it will exclude many other stuff you may need and you should include it by your own.
Define _WINSOCKAPI_ before windows.h or project wide. But when you include WinSock2.h you get macro redefinition warning.
Use windows.h instead of WinSock2.h when winsock.h is enough for your project (in most cases it is). This will probably result in longer compilation time but solves any errors/warnings.

iOS: how to perform a HTTP POST request?

Here is how POST HTTP request works for iOS 8+ using NSURLSession:

- (void)call_PostNetworkingAPI:(NSURL *)url withCompletionBlock:(void(^)(id object,NSError *error,NSURLResponse *response))completion
{
    NSURLSessionConfiguration *config = [NSURLSessionConfiguration defaultSessionConfiguration];
    config.requestCachePolicy = NSURLRequestReloadIgnoringLocalCacheData;
    config.URLCache = nil;
    config.timeoutIntervalForRequest = 5.0f;
    config.timeoutIntervalForResource =10.0f;
    NSURLSession *session = [NSURLSession sessionWithConfiguration:config delegate:nil delegateQueue:nil];
    NSMutableURLRequest *Req=[NSMutableURLRequest requestWithURL:url];
    [Req setHTTPMethod:@"POST"];

    NSURLSessionDataTask *task = [session dataTaskWithRequest:Req completionHandler:^(NSData * _Nullable data, NSURLResponse * _Nullable response, NSError * _Nullable error) {
        if (error == nil) {

            NSDictionary *dict = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:nil];
            if (dict != nil) {
                completion(dict,error,response);
            }
        }else
        {
            completion(nil,error,response);
        }
    }];
    [task resume];

}

Hope this will satisfy your following requirement.

Printing the last column of a line in a file

To print the last column of a line just use $(NF):

awk '{print $(NF)}'

Android ACTION_IMAGE_CAPTURE Intent

I created simple library which will manage choosing images from different sources (Gallery, Camera), maybe save it to some location (SD-Card or internal memory) and return the image back so please free to use it and improve it - Android-ImageChooser.

ReactJS - Call One Component Method From Another Component

Well, actually, React is not suitable for calling child methods from the parent. Some frameworks, like Cycle.js, allow easily access data both from parent and child, and react to it.

Also, there is a good chance you don't really need it. Consider calling it into existing component, it is much more independent solution. But sometimes you still need it, and then you have few choices:

Pass method down, if it is a child (the easiest one, and it is one of the passed properties)
add events library; in React ecosystem Flux approach is the most known, with Redux library. You separate all events into separated state and actions, and dispatch them from components
if you need to use function from the child in a parent component, you can wrap in a third component, and clone parent with augmented props.

UPD: if you need to share some functionality which doesn't involve any state (like static functions in OOP), then there is no need to contain it inside components. Just declare it separately and invoke when need:

let counter = 0;
function handleInstantiate() {
   counter++;
}

constructor(props) {
   super(props);
   handleInstantiate();
}

Programs & Examples On #Portable applications

What's wrong with foreign keys?

div inside table

How do I save JSON to local text file

Removing object properties with Lodash

Querying a linked sql server

Python subprocess.Popen "OSError: [Errno 12] Cannot allocate memory"

How to play YouTube video in my Android application?

Can a table have two foreign keys?

How can one see content of stack with GDB?

Declaring abstract method in TypeScript

How to set conditional breakpoints in Visual Studio?

How comment a JSP expression?

jQuery text() and newlines

php foreach with multidimensional array

Checking if a folder exists (and creating folders) in Qt, C++

MySQL dump by query

What's a good hex editor/viewer for the Mac?

Why, Fatal error: Class 'PHPUnit_Framework_TestCase' not found in ...?

How do I write a correct micro-benchmark in Java?

How can I extract all values from a dictionary in Python?

error MSB6006: "cmd.exe" exited with code 1

Finding the source code for built-in Python functions?

getString Outside of a Context or Activity

Convert datetime to valid JavaScript date

Get the element with the highest occurrence in an array

How to remove a Gitlab project?

How to start jenkins on different port rather than 8080 using command prompt in Windows?

What is the best way to tell if a character is a letter or number in Java without using regexes?

Using number as "index" (JSON)

Is there more to an interface than having the correct methods

Two Divs on the same row and center align both of them

Cannot uninstall angular-cli

Transport endpoint is not connected

Global variables in header file

How to create a DataFrame of random integers with Pandas?

How do I kill all the processes in Mysql "show processlist"?

How can my iphone app detect its own version number?

How to stop and restart memcached server?

Filtering DataGridView without changing datasource

CURRENT_TIMESTAMP in milliseconds

How to add reference to a method parameter in javadoc?

Centering text in a table in Twitter Bootstrap

What are the ways to sum matrix elements in MATLAB?

ViewDidAppear is not called when opening app from background

How can I find the dimensions of a matrix in Python?

subtract time from date - moment js

Delaying a jquery script until everything else has loaded

Get Application Directory

How do I create a MessageBox in C#?

Are duplicate keys allowed in the definition of binary search trees?

auto create database in Entity Framework Core

How to fix 'fs: re-evaluating native module sources is not supported' - graceful-fs

RSA: Get exponent and modulus given a public key

How to remove a field completely from a MongoDB document?

How do you convert Html to plain text?

XMLHttpRequest cannot load file. Cross origin requests are only supported for HTTP

How to implement a SQL like 'LIKE' operator in java?

Full width layout with twitter bootstrap

Update:

How to write a multidimensional array to a text file?

How do I empty an input value with jQuery?

Selection with .loc in python

add allow_url_fopen to my php.ini using .htaccess

How to generate a random alpha-numeric string

Mockito: Mock private field initialization

Using print statements only to debug

How to make button fill table cell

How to Use -confirm in PowerShell

How do I make XAML DataGridColumns fill the entire DataGrid?

How do I echo and send console output to a file in a bat script?

ImportError: No module named matplotlib.pyplot

How to parse month full form string using DateFormat in Java?

LINQ to Entities does not recognize the method

How to increase space between dotted border dots

jQuery: How to detect window width on the fly?

Show all tables inside a MySQL database using PHP?

Can a java lambda have more than 1 parameter?

Chrome blocks different origin requests

Format numbers to strings in Python

Cannot find reference 'xxx' in init.py - Python / Pycharm