Programs & Examples On #Core foundation

Core Foundation provides the fundamental data types and essential services that underlie both the Cocoa and Carbon environments on Mac OS X.

Generate a UUID on iOS from Swift

Try this one:

let uuid = NSUUID().uuidString
print(uuid)

Swift 3/4/5

let uuid = UUID().uuidString
print(uuid)

iOS start Background Thread

If you use performSelectorInBackground:withObject: to spawn a new thread, then the performed selector is responsible for setting up the new thread's autorelease pool, run loop and other configuration details – see "Using NSObject to Spawn a Thread" in Apple's Threading Programming Guide.

You'd probably be better off using Grand Central Dispatch, though:

dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
    [self getResultSetFromDB:docids];
});

GCD is a newer technology, and is more efficient in terms of memory overhead and lines of code.


Updated with a hat tip to Chris Nolet, who suggested a change that makes the above code simpler and keeps up with Apple's latest GCD code examples.

How to link an image and target a new window

<a href="http://www.google.com" target="_blank"> //gives blank window
<img width="220" height="250" border="0" align="center"  src=""/> // show image into new window
</a>

See the code

Git - How to close commit editor?

You Just clicking the key.

first press ESC + enter and then press :x + enter

Determine Pixel Length of String in Javascript/jQuery?

Put it in an absolutely-positioned div then use clientWidth to get the displayed width of the tag. You can even set the visibility to "hidden" to hide the div:

<div id="text" style="position:absolute;visibility:hidden" >This is some text</div>
<input type="button" onclick="getWidth()" value="Go" />
<script type="text/javascript" >
    function getWidth() {
        var width = document.getElementById("text").clientWidth;
        alert(" Width :"+  width);
    }
</script>

invalid use of incomplete type

You need to use a pointer or a reference as the proper type is not known at this time the compiler can not instantiate it.

Instead try:

void action(const typename Subclass::mytype &var) {
            (static_cast<Subclass*>(this))->do_action();
    }

Why is JavaFX is not included in OpenJDK 8 on Ubuntu Wily (15.10)?

According to the packages list in Ubuntu Wily Xenial Bionic there is a package named openjfx. This should be a candidate for what you're looking for:

JavaFX/OpenJFX 8 - Rich client application platform for Java

You can install it via:

sudo apt-get install openjfx

It provides the following JAR files to the OpenJDK installation on Ubuntu systems:

/usr/lib/jvm/java-8-openjdk-amd64/jre/lib/ext/jfxrt.jar
/usr/lib/jvm/java-8-openjdk-amd64/jre/lib/jfxswt.jar
/usr/lib/jvm/java-8-openjdk-amd64/lib/ant-javafx.jar
/usr/lib/jvm/java-8-openjdk-amd64/lib/javafx-mx.jar

If you want to have sources available, for example for debugging, you can additionally install:

sudo apt-get install openjfx-source

Single vs Double quotes (' vs ")

Using " instead of ' when:

<input value="user"/> //Standard html
<input value="user's choice"/> //Need to use single quote
<input onclick="alert('hi')"/> //When giving string as parameter for javascript function

Using ' instead of " when:

<input value='"User"'/> //Need to use double quote
var html = "<input name='username'/>" //When assigning html content to a javascript variable

Android Use Done button on Keyboard to click button

if you want to catch the keyboard enter button for doing your job which you want to done through any event like button click, you can write the below simple code for that text view

Edittext ed= (EditText) findViewById(R.id.edit_text);

ed.setOnEditorActionListener(new TextView.OnEditorActionListener() {
@Override
public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
    if (actionId == EditorInfo.IME_ACTION_DONE) {
        // Do you job here which you want to done through event
    }
    return false;
}
});

How to resolve compiler warning 'implicit declaration of function memset'

memset requires you to import the header string.h file. So just add the following header

#include <string.h>
...

How do I revert all local changes in Git managed project to previous state?

If you want to revert changes made to your working copy, do this:

git checkout .

If you want to revert changes made to the index (i.e., that you have added), do this. Warning this will reset all of your unpushed commits to master!:

git reset

If you want to revert a change that you have committed, do this:

git revert <commit 1> <commit 2>

If you want to remove untracked files (e.g., new files, generated files):

git clean -f

Or untracked directories (e.g., new or automatically generated directories):

git clean -fd

How does origin/HEAD get set?

Disclaimer: this is an update to Cascabel's answer, which I'm writing to save the curious some time.

I tried in vain to replicate (in Git 2.0.1) the remote HEAD is ambiguous message that Cascabel mentions in his answer; so I did a bit of digging (by cloning https://github.com/git/git and searching the log). It used to be that

Determining HEAD is ambiguous since it is done by comparing SHA1s.

In the case of multiple matches we return refs/heads/master if it
matches, else we return the first match we encounter. builtin-remote
needs all matches returned to it, so add a flag for it to request such.

(Commit 4229f1fa325870d6b24fe2a4c7d2ed5f14c6f771, dated Feb 27, 2009, found with git log --reverse --grep="HEAD is ambiguous")

However, the ambiguity in question has since been lifted:

One long-standing flaw in the pack transfer protocol used by "git
clone" was that there was no way to tell the other end which branch
"HEAD" points at, and the receiving end needed to guess.  A new
capability has been defined in the pack protocol to convey this
information so that cloning from a repository with more than one
branches pointing at the same commit where the HEAD is at now
reliably sets the initial branch in the resulting repository.

(Commit 9196a2f8bd46d36a285bdfa03b4540ed3f01f671, dated Nov 8, 2013, found with git log --grep="ambiguous" --grep="HEAD" --all-match)

Edit (thanks to torek):

$ git name-rev --name-only 9196a2f8bd46d36a285bdfa03b4540ed3f01f671
tags/v1.8.4.3~3

This means that, if you're using Git v1.8.4.3 or later, you shouldn't run into any ambiguous-remote-HEAD problem.

Find where python is installed (if it isn't default dir)

  1. First search for PYTHON IDLE from search bar
  2. Open the IDLE and use below commands.

    import sys print(sys.path)

  3. It will give you the path where the python.exe is installed. For eg: C:\Users\\...\python.exe

  4. Add the same path to system environment variable.

Python loop counter in a for loop

enumerate is what you are looking for.

You might also be interested in unpacking:

# The pattern
x, y, z = [1, 2, 3]

# also works in loops:
l = [(28, 'M'), (4, 'a'), (1990, 'r')]
for x, y in l:
    print(x)  # prints the numbers 28, 4, 1990

# and also
for index, (x, y) in enumerate(l):
    print(x)  # prints the numbers 28, 4, 1990

Also, there is itertools.count() so you could do something like

import itertools

for index, el in zip(itertools.count(), [28, 4, 1990]):
    print(el)  # prints the numbers 28, 4, 1990

Maximum on http header values?

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

Using ng-click vs bind within link function of Angular Directive

Shouldn't it simply be:

<button ng-click="clickingCallback()">Click me<button>

Why do you want to write a new directive just to map your click event to a callback on your scope ? ng-click already does that for you.

SQL Server replace, remove all after certain character

For the times when some fields have a ";" and some do not you can also add a semi-colon to the field and use the same method described.

SET MyText = LEFT(MyText+';', CHARINDEX(';',MyText+';')-1)

Can promises have multiple arguments to onFulfilled?

De-structuring Assignment in ES6 would help here.For Ex:

let [arg1, arg2] = new Promise((resolve, reject) => {
    resolve([argument1, argument2]);
});

Java 8 lambdas, Function.identity() or t->t

As of the current JRE implementation, Function.identity() will always return the same instance while each occurrence of identifier -> identifier will not only create its own instance but even have a distinct implementation class. For more details, see here.

The reason is that the compiler generates a synthetic method holding the trivial body of that lambda expression (in the case of x->x, equivalent to return identifier;) and tell the runtime to create an implementation of the functional interface calling this method. So the runtime sees only different target methods and the current implementation does not analyze the methods to find out whether certain methods are equivalent.

So using Function.identity() instead of x -> x might save some memory but that shouldn’t drive your decision if you really think that x -> x is more readable than Function.identity().

You may also consider that when compiling with debug information enabled, the synthetic method will have a line debug attribute pointing to the source code line(s) holding the lambda expression, therefore you have a chance of finding the source of a particular Function instance while debugging. In contrast, when encountering the instance returned by Function.identity() during debugging an operation, you won’t know who has called that method and passed the instance to the operation.

Docker - a way to give access to a host USB or serial device?

If you would like to dynamically access USB devices which can be plugged in while the docker container is already running, for example access a just attached usb webcam at /dev/video0, you can add a cgroup rule when starting the container. This option does not need a --privileged container and only allows access to specific types of hardware.

Step 1

Check the device major number of the type of device you would like to add. You can look it up in the linux kernel documentation. Or you can check it for your device. For example to check the device major number for a webcam connected to /dev/video0, you can do a ls -la /dev/video0. This results in something like:

crw-rw----+ 1 root video 81, 0 Jul  6 10:22 /dev/video0

Where the first number (81) is the device major number. Some common device major numbers:

  • 81: usb webcams
  • 188: usb to serial converters

Step 2

Add rules when you start the docker container:

  • Add a --device-cgroup-rule='c major_number:* rmw' rule for every type of device you want access to
  • Add access to udev information so docker containers can get more info on your usb devices with -v /run/udev:/run/udev:ro
  • Map the /dev volume to your docker container with -v /dev:/dev

Wrap up

So to add all usb webcams and serial2usb devices to your docker container, do:

docker run -it -v /dev:/dev --device-cgroup-rule='c 188:* rmw' --device-cgroup-rule='c 81:* rmw' ubuntu bash

How can I get my Android device country code without using GPS?

There isn't any need to call any API. You can get the country code from your device where it is located. Just use this function:

 fun getUserCountry(context: Context): String? {
    try {
        val tm = context.getSystemService(Context.TELEPHONY_SERVICE) as TelephonyManager
        val simCountry = tm.simCountryIso
        if (simCountry != null && simCountry.length == 2) { // SIM country code is available
            return simCountry.toLowerCase(Locale.US)
        } 
        else if (tm.phoneType != TelephonyManager.PHONE_TYPE_CDMA) { // Device is not 3G (would be unreliable)
            val networkCountry = tm.networkCountryIso
            if (networkCountry != null && networkCountry.length == 2) { // network country code is available
                return networkCountry.toLowerCase(Locale.US)
            }
        }
    }
    catch (e: Exception) {
    }
    return null
}

Flutter: Run method on Widget build complete

Flutter 1.2 - dart 2.2

According with the official guidelines and sources if you want to be certain that also the last frame of your layout was drawned you can write for example:

import 'package:flutter/scheduler.dart';

void initState() {
   super.initState();
   if (SchedulerBinding.instance.schedulerPhase == SchedulerPhase.persistentCallbacks) {
        SchedulerBinding.instance.addPostFrameCallback((_) => yourFunction(context));
   }
}

Fixing Segmentation faults in C++

I don't know of any methodology to use to fix things like this. I don't think it would be possible to come up with one either for the very issue at hand is that your program's behavior is undefined (I don't know of any case when SEGFAULT hasn't been caused by some sort of UB).

There are all kinds of "methodologies" to avoid the issue before it arises. One important one is RAII.

Besides that, you just have to throw your best psychic energies at it.

Use of contains in Java ArrayList<String>

Yes, that should work for Strings, but if you are worried about duplicates use a Set. This collection prevents duplicates without you having to do anything. A HashSet is OK to use, but it is unordered so if you want to preserve insertion order you use a LinkedHashSet.

How to get random value out of an array?

PHP provides a function just for that: array_rand()
http://php.net/manual/en/function.array-rand.php

$ran = array(1,2,3,4);
$randomElement = $ran[array_rand($ran, 1)];

Difference between clustered and nonclustered index

A clustered index alters the way that the rows are stored. When you create a clustered index on a column (or a number of columns), SQL server sorts the table’s rows by that column(s). It is like a dictionary, where all words are sorted in alphabetical order in the entire book.

A non-clustered index, on the other hand, does not alter the way the rows are stored in the table. It creates a completely different object within the table that contains the column(s) selected for indexing and a pointer back to the table’s rows containing the data. It is like an index in the last pages of a book, where keywords are sorted and contain the page number to the material of the book for faster reference.

The Response content must be a string or object implementing __toString(), "boolean" given after move to psql

I got this issue when I used an ajax call to retrieve data from the database. When the controller returned the array it converted it to a boolean. The problem was that I had "invalid characters" like ú (u with accent).

mysql data directory location

If the software is Sequel pro the default install mysql on Mac OSX has data located here:

/usr/local/var/mysql

Using a BOOL property

Apple simply recommends declaring an isX getter for stylistic purposes. It doesn't matter whether you customize the getter name or not, as long as you use the dot notation or message notation with the correct name. If you're going to use the dot notation it makes no difference, you still access it by the property name:

@property (nonatomic, assign) BOOL working;

[self setWorking:YES];         // Or self.working = YES;
BOOL working = [self working]; // Or = self.working;

Or

@property (nonatomic, assign, getter=isWorking) BOOL working;

[self setWorking:YES];           // Or self.working = YES;, same as above
BOOL working = [self isWorking]; // Or = self.working;, also same as above

Microsoft.Office.Core Reference Missing

You can add reference of Microsoft.Office.Core from COM components tab in the add reference window by adding reference of Microsoft Office 12.0 Object Library. The screen shot will shows what component you need.

enter image description here

What's the best way to send a signal to all members of a process group?

This script also work:

#/bin/sh while true do echo "Enter parent process id [type quit for exit]" read ppid if [ $ppid -eq "quit" -o $ppid -eq "QUIT" ];then exit 0 fi for i in `ps -ef| awk '$3 == '$ppid' { print $2 }'` do echo killing $i kill $i done done

Oracle PL/SQL : remove "space characters" from a string

I'd go for regexp_replace, although I'm not 100% sure this is usable in PL/SQL

my_value := regexp_replace(my_value, '[[:space:]]*',''); 

How to execute python file in linux

You have to add a shebang. A shebang is the first line of the file. Its what the system is looking for in order to execute a file.

It should look like that :

#!/usr/bin/env python

or the real path

#!/usr/bin/python

You should also check the file have the right to be execute. chmod +x file.py

As Fabian said, take a look to Wikipedia : Wikipedia - Shebang (en)

How to check if a folder exists

Generate a file from the string of your folder directory

String path="Folder directory";    
File file = new File(path);

and use method exist.
If you want to generate the folder you sould use mkdir()

if (!file.exists()) {
            System.out.print("No Folder");
            file.mkdir();
            System.out.print("Folder created");
        }

How do I import .sql files into SQLite 3?

From a sqlite prompt:

sqlite> .read db.sql

Or:

cat db.sql | sqlite3 database.db

Also, your SQL is invalid - you need ; on the end of your statements:

create table server(name varchar(50),ipaddress varchar(15),id init);
create table client(name varchar(50),ipaddress varchar(15),id init);

IIS: Idle Timeout vs Recycle

IIS now has

Idle Time-out Action : Suspend setting

Suspending is just freezes the process and it is much more efficient than the destroying the process.

MongoDB: How to find out if an array field contains an element?

I am trying to explain by putting problem statement and solution to it. I hope it will help

Problem Statement:

Find all the published products, whose name like ABC Product or PQR Product, and price should be less than 15/-

Solution:

Below are the conditions that need to be taken care of

  1. Product price should be less than 15
  2. Product name should be either ABC Product or PQR Product
  3. Product should be in published state.

Below is the statement that applies above criterion to create query and fetch data.

$elements = $collection->find(
             Array(
                [price] => Array( [$lt] => 15 ),
                [$or] => Array(
                            [0]=>Array(
                                    [product_name]=>Array(
                                       [$in]=>Array(
                                            [0] => ABC Product,
                                            [1]=> PQR Product
                                            )
                                        )
                                    )
                                ),
                [state]=>Published
                )
            );

How to print Boolean flag in NSLog?

While this is not a direct answer to Devang's question I believe that the below macro can be very helpful to people looking to log BOOLs. This will log out the value of the bool as well as automatically labeling it with the name of the variable.

#define LogBool(BOOLVARIABLE) NSLog(@"%s: %@",#BOOLVARIABLE, BOOLVARIABLE ? @"YES" : @"NO" )

BOOL success = NO;
LogBool(success); // Prints out 'success: NO' to the console

success = YES;
LogBool(success); // Prints out 'success: YES' to the console

Twitter bootstrap scrollable modal

I´ve done a tiny solution using only jQuery.

First, you need to put an additional class to your <div class="modal-body"> I called "ativa-scroll", so it becomes something like this:

<div class="modal-body ativa-scroll">

So now just put this piece of code on your page, near your JS loading:

<script type="text/javascript">
  $(document).ready(ajustamodal);
  $(window).resize(ajustamodal);
  function ajustamodal() {
    var altura = $(window).height() - 155; //value corresponding to the modal heading + footer
    $(".ativa-scroll").css({"height":altura,"overflow-y":"auto"});
  }
</script>

I works perfectly for me, also in a responsive way! :)

Function to close the window in Tkinter

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

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

app = App()

How to upgrade PowerShell version from 2.0 to 3.0

As of today, Windows PowerShell 5.1 is the latest version. It can be installed as part of Windows Management Framework 5.1. It was released in January 2017.

Quoting from the official Microsoft download page here.

Some of the new and updated features in this release include:

  • Constrained file copying to/from JEA endpoints
  • JEA support for Group Managed Service Accounts and Conditional Access Policies
  • PowerShell console support for VT100 and redirecting stdin with interactive input
  • Support for catalog signed modules in PowerShell Get
  • Specifying which module version to load in a script
  • Package Management cmdlet support for proxy servers
  • PowerShellGet cmdlet support for proxy servers
  • Improvements in PowerShell Script Debugging
  • Improvements in Desired State Configuration (DSC)
  • Improved PowerShell usage auditing using Transcription and Logging
  • New and updated cmdlets based on community feedback

Subscript out of range error in this Excel VBA script

Private Sub CommandButton1_Click()

    Dim Data As Object, Employee As Object

    Application.ScreenUpdating = False

    Set Data = ThisWorkbook.Sheets("Data")

    Set Employee = ThisWorkbook.Sheets("Employee Names")

    Data.Range("AK1").Value = "Lookup"

    Data.Range("AK2:AK" & Data.Range("A1").End(xlDown).Row).Formula = "=VLOOKUP(E2,'Employee Names'!$A:$A,1,0)"

    Data.Range("AK2:AK" & Data.Range("A1").End(xlDown).Row).Value = Data.Range("AK2:AK" & Data.Range("A1").End(xlDown).Row).Value

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=5, Criteria1:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=37, Criteria1:="#N/A"

    Application.DisplayAlerts = False

    Data.AutoFilter.Range.Offset(1, 0).Rows.SpecialCells(xlCellTypeVisible).Delete (xlShiftUp)

    Data.Range("AK:AK").Delete

    Data.AutoFilterMode = False

    'Selection.AutoFilter

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=7, Criteria1:="="

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=12, Criteria1:="<>"

    Worksheets("Data").Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "DrfeeRequested"

    Set Dr = ThisWorkbook.Worksheets("DrfeeRequested")

    Dr.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.AutoFilterMode = False

    'DrfeeRequested.AutoFilterMode = False

    Selection.AutoFilter

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=13, Criteria1:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "RateLockfollowup"
    Set Ratefolup = ThisWorkbook.Worksheets("RateLockfollowup")

    Ratefolup.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.AutoFilterMode = False

    Selection.AutoFilter

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=19, Criteria1:="="

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=13, Criteria1:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "Lockedlefollowup"
    Set Lockfolup = ThisWorkbook.Worksheets("Lockedlefollowup")

    Lockfolup.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.AutoFilterMode = False

    Selection.AutoFilter

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=19, Criteria1:="="

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "Hoifollowup"

    Set Hoifolup = ThisWorkbook.Worksheets("Hoifollowup")

    Hoifolup.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.AutoFilterMode = False

    Selection.AutoFilter

    TodayDT = Format(Now())

    Weekdy = Weekday(Now())

    If Weekdy = 2 Then
       LastTwoDays = Now() - Weekday(Now(), 3)
    ElseIf Weekdy = 3 Then
       LastTwoDays = Now() - Weekday(Now(), 3)
    ElseIf Weekdy = 4 Then
       LastTwoDays = Now() - Weekday(Now(), 3)
    ElseIf Weekdy = 5 Then
       LastTwoDays = Now() - Weekday(Now(), 3)
    ElseIf Weekdy = 6 Then
       LastTwoDays = Now() - Weekday(Now(), 3)
    Else
       MsgBox "Today Satuarday OR Sunday Data is not Available"
    End If

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=12, Criteria1:="="

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=11, Criteria1:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=11, Criteria1:=" TodayDT", Operator:=xlAnd, Criteria2:="LastTwoDays"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "DRfeefollowup"

    Set Drfreefolup = ThisWorkbook.Worksheets("DRfeefollowup")

    Drfreefolup.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.AutoFilterMode = False

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=15, Criteria1:="yes"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=19, Criteria1:="x"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=12, Criteria1:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=13, Criteria1:="<>"

    'Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).AutoFilter Field:=14, criterial:="<>"

    Data.Range("A1:AK" & Data.Range("A1").End(xlDown).Row).Copy

    Sheets.Add(After:=Sheets(Sheets.Count)).Name = "Drworkblefiles"

    Set Drworkblefiles = ThisWorkbook.Worksheets("Drworkblefiles")

    Drworkblefiles.Range("A1").PasteSpecial Paste:=xlPasteValues

    Application.CutCopyMode = False

    Data.Range("A1").AutoFilter

   End Sub

 Private Sub CommandButton2_Click()


    Sheets("Data").Range("A1:AJ" & Sheets("Data").Range("A1").End(xlDown).Row).Clear

    MsgBox "Please paste new data in data sheet"


End Sub

How do I get column names to print in this C# program?

Print datatable rows with column

Here is solution 

DataTable datatableinfo= new DataTable();

// Fill data table 

//datatableinfo=fill by function or get data from database

//Print data table with rows and column


for (int j = 0; j < datatableinfo.Rows.Count; j++)
{
    for (int i = 0; i < datatableinfo.Columns.Count; i++)    
        {    
            Console.Write(datatableinfo.Columns[i].ColumnName + " ");    
            Console.WriteLine(datatableinfo.Rows[j].ItemArray[i]+" "); 
        }
}


Ouput :
ColumnName - row Value
ColumnName - row Value
ColumnName - row Value
ColumnName - row Value

Export to csv in jQuery

Hope the following demo can help you out.

_x000D_
_x000D_
$(function() {_x000D_
  $("button").on('click', function() {_x000D_
    var data = "";_x000D_
    var tableData = [];_x000D_
    var rows = $("table tr");_x000D_
    rows.each(function(index, row) {_x000D_
      var rowData = [];_x000D_
      $(row).find("th, td").each(function(index, column) {_x000D_
        rowData.push(column.innerText);_x000D_
      });_x000D_
      tableData.push(rowData.join(","));_x000D_
    });_x000D_
    data += tableData.join("\n");_x000D_
    $(document.body).append('<a id="download-link" download="data.csv" href=' + URL.createObjectURL(new Blob([data], {_x000D_
      type: "text/csv"_x000D_
    })) + '/>');_x000D_
_x000D_
_x000D_
    $('#download-link')[0].click();_x000D_
    $('#download-link').remove();_x000D_
  });_x000D_
});
_x000D_
table {_x000D_
  border-collapse: collapse;_x000D_
}_x000D_
_x000D_
td,_x000D_
th {_x000D_
  border: 1px solid #aaa;_x000D_
  padding: 0.5rem;_x000D_
  text-align: left;_x000D_
}_x000D_
_x000D_
td {_x000D_
  font-size: 0.875rem;_x000D_
}_x000D_
_x000D_
.btn-group {_x000D_
  padding: 1rem 0;_x000D_
}_x000D_
_x000D_
button {_x000D_
  background-color: #fff;_x000D_
  border: 1px solid #000;_x000D_
  margin-top: 0.5rem;_x000D_
  border-radius: 3px;_x000D_
  padding: 0.5rem 1rem;_x000D_
  font-size: 1rem;_x000D_
}_x000D_
_x000D_
button:hover {_x000D_
  cursor: pointer;_x000D_
  background-color: #000;_x000D_
  color: #fff;_x000D_
}
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
_x000D_
<div id='PrintDiv'>_x000D_
  <table id="mainTable">_x000D_
    <tr>_x000D_
      <td>Col1</td>_x000D_
      <td>Col2</td>_x000D_
      <td>Col3</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>Val1</td>_x000D_
      <td>Val2</td>_x000D_
      <td>Val3</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>Val11</td>_x000D_
      <td>Val22</td>_x000D_
      <td>Val33</td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
      <td>Val111</td>_x000D_
      <td>Val222</td>_x000D_
      <td>Val333</td>_x000D_
    </tr>_x000D_
  </table>_x000D_
</div>_x000D_
_x000D_
<div class="btn-group">_x000D_
  <button>csv</button>_x000D_
</div>
_x000D_
_x000D_
_x000D_

How to create Android Facebook Key Hash?

this will help newbees also.

just adding more details to @coder_For_Life22's answer.

if this answer helps you don't forget to upvote. it motivates us.

for this you must already know the path of the app's keystore file and password

for this example consider the key is stored at "c:\keystorekey\new.jks"

1. open this page https://code.google.com/archive/p/openssl-for-windows/downloads

2. download 32 or 64 bit zip file as per your windows OS.

3. extract the downloaded file where ever you want and remember the path.

4. for this example we consider that you have extracted the folder in download folder.

so the file address will be "C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe";

5. now on keyboard press windows+r button.

6. this will open run box.

7. type cmd and press Ctrl+Shift+Enter.

8. this will open command prompt as administrator.

9. here navigate to java's bin folder:

if you use jre provided by Android Studio you will find the path as follows:
a. open android studio.
b. file->project structure
c. in the left pane, click 'SDK location'
d. in the right pane, below 'JDK location' is your jre path.
e. add "\bin" at the end of this path as the file "keytool.exe", we need, is inside this folder.
for this example i consider, you have installed java separately and following is the path
"C:\Program Files\Java\jre-10.0.2\bin"
if you have installed 32bit java it will be in
"C:\Program Files (x86)\Java\jre-10.0.2\bin"
10. now with above paths execute command as following:

keytool -exportcert -alias androiddebugkey -keystore "c:\keystorekey\new.jks" | "C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe" sha1 -binary |"C:\Users\0\Downloads\openssl-0.9.8e_X64\bin\openssl.exe" base64
  1. You will be asked for password, give the password you have given when creating keystore key.

    !!!!!! this will give you the key

errors: if you get:
---
'keytool' is not recognized as an internal or external command
---
this means that java is installed somewhere else.

How to stop mysqld

For MAMP

  1. Stop servers (but you may notice MySQL stays on)
  2. Remove or rename /Applications/MAMP/tmp/mysql/ which holds the mysql.pid and mysql.sock.lock files
  3. When you go back to Mamp, you'll see MySQL is now off. You can "Start Servers" again.

Find all files in a folder

First off; best practice would be to get the users Desktop folder with

string path = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);

Then you can find all the files with something like

string[] files = Directory.GetFiles(path, "*.txt", SearchOption.AllDirectories);

Note that with the above line you will find all files with a .txt extension in the Desktop folder of the logged in user AND all subfolders.

Then you could copy or move the files by enumerating the above collection like

// For copying...
foreach (string s in files)
{
   File.Copy(s, "C:\newFolder\newFilename.txt");
}

// ... Or for moving
foreach (string s in files)
{
   File.Move(s, "C:\newFolder\newFilename.txt");
}

Please note that you will have to include the filename in your Copy() (or Move()) operation. So you would have to find a way to determine the filename of at least the extension you are dealing with and not name all the files the same like what would happen in the above example.

With that in mind you could also check out the DirectoryInfo and FileInfo classes. These work in similair ways, but you can get information about your path-/filenames, extensions, etc. more easily

Check out these for more info:

http://msdn.microsoft.com/en-us/library/system.io.directory.aspx

http://msdn.microsoft.com/en-us/library/ms143316.aspx

http://msdn.microsoft.com/en-us/library/system.io.file.aspx

Prevent direct access to a php include file

debug_backtrace() || die ("Direct access not permitted");

Is it possible to convert char[] to char* in C?

If you have char[] c then you can do char* d = &c[0] and access element c[1] by doing *(d+1), etc.

jQuery $("#radioButton").change(...) not firing during de-selection

The change event not firing on deselection is the desired behaviour. You should run a selector over the entire radio group rather than just the single radio button. And your radio group should have the same name (with different values)

Consider the following code:

$('input[name="job[video_need]"]').on('change', function () {
    var value;
    if ($(this).val() == 'none') {
        value = 'hide';
    } else {
        value = 'show';
    }
    $('#video-script-collapse').collapse(value);
});

I have same use case as yours i.e. to show an input box when a particular radio button is selected. If the event was fired on de-selection as well, I would get 2 events each time.

Getting HTTP code in PHP using curl

Here is my solution need get Status Http for checking status of server regularly

$url = 'http://www.example.com'; // Your server link

while(true) {

    $strHeader = get_headers($url)[0];

    $statusCode = substr($strHeader, 9, 3 );

    if($statusCode != 200 ) {
        echo 'Server down.';
        // Send email 
    }
    else {
        echo 'oK';
    }

    sleep(30);
}

how to convert 2d list to 2d numpy array?

I am using large data sets exported to a python file in the form

XVals1 = [.........] 
XVals2 = [.........] 

Each list is of identical length. I use

>>> a1 = np.array(SV.XVals1)

>>> a2 = np.array(SV.XVals2)

Then

>>> A = np.matrix([a1,a2])

UILabel is not auto-shrinking text to fit label size

Well in the end i didn't find my answer. And i think the autoshrink doesn't work for multiple lines. I ended up using suggestion in this link: autoshrink on a UILabel with multiple lines

The solutions is to calulate text height at given width and if text is bigger, to shrink font size and then do he same again until the height is equal or less than your needed size.

I don't understand why this should be so hard to implement. If i'm missing something, everyone is welcome to correct me :)

Can't Find Theme.AppCompat.Light for New Android ActionBar Support

http://developer.android.com/tools/support-library/setup.html has a bug. In Property->Java build path->'Project' and 'Order and Export', there should not be any jar's. Removing them, and checking 'Android Private Libraries' and 'Android Dependencies' solved my problem.

How to find the array index with a value?

Use jQuery's function jQuery.inArray

jQuery.inArray( value, array [, fromIndex ] )
(or) $.inArray( value, array [, fromIndex ] )

Enabling CORS in Cloud Functions for Firebase

Changing true by "*" did the trick for me, so this is how it looks like:

const cors = require('cors')({ origin: "*" })

I tried this approach because in general, this is how this response header is set:

'Access-Control-Allow-Origin', '*'

Be aware that this will allow any domain to call your endpoints therefore it's NOT secure.

Additionally, you can read more on the docs: https://github.com/expressjs/cors

How to distinguish mouse "click" and "drag"

Using jQuery with a 5 pixel x/y theshold to detect the drag:

var dragging = false;
$("body").on("mousedown", function(e) {
  var x = e.screenX;
  var y = e.screenY;
  dragging = false;
  $("body").on("mousemove", function(e) {
    if (Math.abs(x - e.screenX) > 5 || Math.abs(y - e.screenY) > 5) {
      dragging = true;
    }
  });
});
$("body").on("mouseup", function(e) {
  $("body").off("mousemove");
  console.log(dragging ? "drag" : "click");
});

How to persist data in a dockerized postgres database using volumes

I would avoid using a relative path. Remember that docker is a daemon/client relationship.

When you are executing the compose, it's essentially just breaking down into various docker client commands, which are then passed to the daemon. That ./database is then relative to the daemon, not the client.

Now, the docker dev team has some back and forth on this issue, but the bottom line is it can have some unexpected results.

In short, don't use a relative path, use an absolute path.

Convert string to Color in C#

For transferring colors via xml-strings I've found out:

Color x = Color.Red; // for example
String s = x.ToArgb().ToString()
... to/from xml ...
Int32 argb = Convert.ToInt32(s);
Color red = Color.FromArgb(argb);

Fastest way to download a GitHub project

Downloading with Git using Windows CMD from a GitHub project

You can get download the link from GitHub <b>HTTPS clone URL</b>

Download with Window Command Prompt cmd for above picture HTTPS clone URL

  1. Copy the HTTPS clone URL shown in picture 1

  2. Open CMD

  3. git clone //paste the URL show in picture 2

Update and left outer join statements

The Left join in this query is pointless:

UPDATE md SET md.status = '3' 
FROM pd_mounting_details AS md 
LEFT OUTER JOIN pd_order_ecolid AS oe ON md.order_data = oe.id

It would update all rows of pd_mounting_details, whether or not a matching row exists in pd_order_ecolid. If you wanted to only update matching rows, it should be an inner join.

If you want to apply some condition based on the join occurring or not, you need to add a WHERE clause and/or a CASE expression in your SET clause.

Sharing a URL with a query string on Twitter

If you add it manual on html site, just replace:

&

With

&amp;

Standard html code for &

IIS7 URL Redirection from root to sub directory

I could not get this working with the accepted answer, mainly because I did not know where to enter that code. I looked everywhere for some explanation of the URL Rewrite tool that made sense, but could not find any. I ended up using the HTTP Redirect tool in IIS.

  1. Choose your site
  2. Click HTTP Redirect in the IIS section (Make sure the Role Service is installed)
  3. Check "Redirect requests to this destination"
  4. Enter where you want to redirect. In your case "wwww.mysite.com/menu_1/MainScreen.aspx"
  5. In Redirect Behavior, I found I had to check "Only redirect requests to content in this directory (not subdirectories), or it would go into a loop. See what works for you.

Hope this helps.

Converting a String to a List of Words?

You can try and do this:

tryTrans = string.maketrans(",!", "  ")
str = "This is a string, with words!"
str = str.translate(tryTrans)
listOfWords = str.split()

Where to find the win32api module for Python?

I've found that UC Irvine has a great collection of python modules, pywin32 (win32api) being one of many listed there. I'm not sure how they do with keeping up with the latest versions of these modules but it hasn't let me down yet.

UC Irvine Python Extension Repository - http://www.lfd.uci.edu/~gohlke/pythonlibs

pywin32 module - http://www.lfd.uci.edu/~gohlke/pythonlibs/#pywin32

How to use Global Variables in C#?

First examine if you really need a global variable instead using it blatantly without consideration to your software architecture.

Let's assuming it passes the test. Depending on usage, Globals can be hard to debug with race conditions and many other "bad things", it's best to approach them from an angle where you're prepared to handle such bad things. So,

  1. Wrap all such Global variables into a single static class (for manageability).
  2. Have Properties instead of fields(='variables'). This way you have some mechanisms to address any issues with concurrent writes to Globals in the future.

The basic outline for such a class would be:

public class Globals
{
    private static bool _expired;
    public static bool Expired 
    {
        get
        {
            // Reads are usually simple
            return _expired;
        }
        set
        {
            // You can add logic here for race conditions,
            // or other measurements
            _expired = value;
        }
    }
    // Perhaps extend this to have Read-Modify-Write static methods
    // for data integrity during concurrency? Situational.
}

Usage from other classes (within same namespace)

// Read
bool areWeAlive = Globals.Expired;

// Write
// past deadline
Globals.Expired = true;

Interface type check with Typescript

TypeGuards

interface MyInterfaced {
    x: number
}

function isMyInterfaced(arg: any): arg is MyInterfaced {
    return arg.x !== undefined;
}

if (isMyInterfaced(obj)) {
    (obj as MyInterfaced ).x;
}

Sticky Header after scrolling down

Here is a JS fiddle http://jsfiddle.net/ke9kW/1/

As the others say, set the header to fixed, and start it with display: none

then jQuery

$(window).scroll(function () {
  if ( $(this).scrollTop() > 200 && !$('header').hasClass('open') ) {
    $('header').addClass('open');
    $('header').slideDown();
   } else if ( $(this).scrollTop() <= 200 ) {
    $('header').removeClass('open');
    $('header').slideUp();
  }
});

where 200 is the height in pixels you'd like it to move down at. The addition of the open class is to allow us to run an elseif instead of just else, so some of the code doesn't unnecessarily run on every scrollevent, save a lil bit of memory

How to uninstall mini conda? python

your have to comment that line in ~/.bashrc:

#export PATH=/home/jolth/miniconda3/bin:$PATH

and run:

source ~/.bashrc

Stack array using pop() and push()

 public class Stack {
     int[] arr;
     int MAX_SIZE;
     int top;

public Stack(int n){
    MAX_SIZE = n;
    arr = new int[MAX_SIZE];
    top=0;
}

    public boolean isEmpty(){
        if(top ==0)
            return true;
      else
        return false;
   }

public boolean push(int ele){

    if(top<MAX_SIZE){
        arr[top] = ele;
        top++;
        return true;
    }
    else{
        System.out.println("Stack is full");
        return false;
    }
}
public void show(){
    for(int element:arr){
        System.out.print(element+" ");
    }
}
public int size(){
    return top;
}
   public int peek(){
        if(!isEmpty()){
            int peekTest = arr[top-1];
            return peekTest;
                    }
   else{
       System.out.println("Stack is empty");
       return 0;
   } 
}
public int pop(){
    if(isEmpty()){
        System.out.println("Stack is Emmpty");
        return 0;
    }
    else{
        int element = arr[--top];
        return element;
    }
}

}

Inserting a Python datetime.datetime object into MySQL

For a time field, use:

import time    
time.strftime('%Y-%m-%d %H:%M:%S')

I think strftime also applies to datetime.

jQuery callback for multiple ajax calls

Not seeing the need for any object malarky myself. Simple have a variable which is an integer. When you start a request, increment the number. When one completes, decrement it. When it's zero, there are no requests in progress, so you're done.

$('#button').click(function() {
    var inProgress = 0;

    function handleBefore() {
        inProgress++;
    };

    function handleComplete() {
        if (!--inProgress) {
            // do what's in here when all requests have completed.
        }
    };

    $.ajax({
        beforeSend: handleBefore,
        complete: function () {
            // whatever
            handleComplete();
            // whatever
        }
    });
    $.ajax({
        beforeSend: handleBefore,
        complete: function () {
            // whatever
            handleComplete();
            // whatever
        }
    });
    $.ajax({
        beforeSend: handleBefore,
        complete: function () {
            // whatever
            handleComplete();
            // whatever
        }
    });
});

Proxy setting for R

If you start R from a desktop icon, you can add the --internet flag to the target line (right click -> Properties) e.g.

"C:\Program Files\R\R-2.8.1\bin\Rgui.exe" --internet2 

Rotate axis text in python matplotlib

Many "correct" answers here but I'll add one more since I think some details are left out of several. The OP asked for 90 degree rotation but I'll change to 45 degrees because when you use an angle that isn't zero or 90, you should change the horizontal alignment as well; otherwise your labels will be off-center and a bit misleading (and I'm guessing many people who come here want to rotate axes to something other than 90).

Easiest / Least Code

Option 1

plt.xticks(rotation=45, ha='right')

As mentioned previously, that may not be desirable if you'd rather take the Object Oriented approach.

Option 2

Another fast way (it's intended for date objects but seems to work on any label; doubt this is recommended though):

fig.autofmt_xdate(rotation=45)

fig you would usually get from:

  • fig = plt.figure()
  • fig, ax = plt.subplots()
  • fig = ax.figure

Object-Oriented / Dealing directly with ax

Option 3a

If you have the list of labels:

labels = ['One', 'Two', 'Three']
ax.set_xticklabels(labels, rotation=45, ha='right')

Option 3b

If you want to get the list of labels from the current plot:

# Unfortunately you need to draw your figure first to assign the labels,
# otherwise get_xticklabels() will return empty strings.
plt.draw()
ax.set_xticklabels(ax.get_xticklabels(), rotation=45, ha='right')

Option 4

Similar to above, but loop through manually instead.

for label in ax.get_xticklabels():
  label.set_rotation(45)
  label.set_ha('right')

Option 5

We still use pyplot (as plt) here but it's object-oriented because we're changing the property of a specific ax object.

plt.setp(ax.get_xticklabels(), rotation=45, ha='right')

Option 6

This option is simple, but AFAIK you can't set label horizontal align this way so another option might be better if your angle is not 90.

ax.tick_params(axis='x', labelrotation=45)

Edit: There's discussion of this exact "bug" and a fix is potentially slated for v3.2.0: https://github.com/matplotlib/matplotlib/issues/13774

Use of the MANIFEST.MF file in Java

The content of the Manifest file in a JAR file created with version 1.0 of the Java Development Kit is the following.

Manifest-Version: 1.0

All the entries are as name-value pairs. The name of a header is separated from its value by a colon. The default manifest shows that it conforms to version 1.0 of the manifest specification. The manifest can also contain information about the other files that are packaged in the archive. Exactly what file information is recorded in the manifest will depend on the intended use for the JAR file. The default manifest file makes no assumptions about what information it should record about other files, so its single line contains data only about itself. Special-Purpose Manifest Headers

Depending on the intended role of the JAR file, the default manifest may have to be modified. If the JAR file is created only for the purpose of archival, then the MANIFEST.MF file is of no purpose. Most uses of JAR files go beyond simple archiving and compression and require special information to be in the manifest file. Summarized below are brief descriptions of the headers that are required for some special-purpose JAR-file functions

Applications Bundled as JAR Files: If an application is bundled in a JAR file, the Java Virtual Machine needs to be told what the entry point to the application is. An entry point is any class with a public static void main(String[] args) method. This information is provided in the Main-Class header, which has the general form:

Main-Class: classname

The value classname is to be replaced with the application's entry point.

Download Extensions: Download extensions are JAR files that are referenced by the manifest files of other JAR files. In a typical situation, an applet will be bundled in a JAR file whose manifest references a JAR file (or several JAR files) that will serve as an extension for the purposes of that applet. Extensions may reference each other in the same way. Download extensions are specified in the Class-Path header field in the manifest file of an applet, application, or another extension. A Class-Path header might look like this, for example:

Class-Path: servlet.jar infobus.jar acme/beans.jar

With this header, the classes in the files servlet.jar, infobus.jar, and acme/beans.jar will serve as extensions for purposes of the applet or application. The URLs in the Class-Path header are given relative to the URL of the JAR file of the applet or application.

Package Sealing: A package within a JAR file can be optionally sealed, which means that all classes defined in that package must be archived in the same JAR file. A package might be sealed to ensure version consistency among the classes in your software or as a security measure. To seal a package, a Name header needs to be added for the package, followed by a Sealed header, similar to this:

Name: myCompany/myPackage/
Sealed: true

The Name header's value is the package's relative pathname. Note that it ends with a '/' to distinguish it from a filename. Any headers following a Name header, without any intervening blank lines, apply to the file or package specified in the Name header. In the above example, because the Sealed header occurs after the Name: myCompany/myPackage header, with no blank lines between, the Sealed header will be interpreted as applying (only) to the package myCompany/myPackage.

Package Versioning: The Package Versioning specification defines several manifest headers to hold versioning information. One set of such headers can be assigned to each package. The versioning headers should appear directly beneath the Name header for the package. This example shows all the versioning headers:

Name: java/util/
Specification-Title: "Java Utility Classes" 
Specification-Version: "1.2"
Specification-Vendor: "Sun Microsystems, Inc.".
Implementation-Title: "java.util" 
Implementation-Version: "build57"
Implementation-Vendor: "Sun Microsystems, Inc."

'ng' is not recognized as an internal or external command, operable program or batch file

This issue also bother me and then i find possible cases to reproduce this issue

when i run my window in administrator then it working fine ng but when i run this in my second space like other user then i got this issue.

so if i want to run my angular application then i need to run this command

npm run ng serve which is working but when i run the command with --host npm run ng server --host IP it not working given some error

so i find some possible solution 1. go appdata and then user\admin\AppData\Roaming\npm folder then copy this path but if you using other user account user\newuser\AppData\Roaming\npm folder you can copy this npm folder from other user i.e admin user account. if you do not want to copy this folder then copy the path of ****user\admin\AppData\Roaming\npm folder**** folder and then open your environment variable setting and add this path in path variable name

enter this path in system path variable not user variable C:\Users\admin\AppData\Roaming\npm

enter image description here enter image description here and run the command prompt as administrator then run ng command it will work enter image description here enter image description here enter image description here

How can I change the remote/target repository URL on Windows?

Take a look in .git/config and make the changes you need.

Alternatively you could use

git remote rm [name of the url you sets on adding]

and

git remote add [name] [URL]

Or just

git remote set-url [URL]

Before you do anything wrong, double check with

git help remote

How to copy data from one HDFS to another HDFS?

DistCp (distributed copy) is a tool used for copying data between clusters. It uses MapReduce to effect its distribution, error handling and recovery, and reporting. It expands a list of files and directories into input to map tasks, each of which will copy a partition of the files specified in the source list.

Usage: $ hadoop distcp <src> <dst>

example: $ hadoop distcp hdfs://nn1:8020/file1 hdfs://nn2:8020/file2

file1 from nn1 is copied to nn2 with filename file2

Distcp is the best tool as of now. Sqoop is used to copy data from relational database to HDFS and vice versa, but not between HDFS to HDFS.

More info:

There are two versions available - runtime performance in distcp2 is more compared to distcp

How do I make the method return type generic?

This question is very similar to Item 29 in Effective Java - "Consider typesafe heterogeneous containers." Laz's answer is the closest to Bloch's solution. However, both put and get should use the Class literal for safety. The signatures would become:

public <T extends Animal> void addFriend(String name, Class<T> type, T animal);
public <T extends Animal> T callFriend(String name, Class<T> type);

Inside both methods you should check that the parameters are sane. See Effective Java and the Class javadoc for more info.

Jenkins returned status code 128 with github

i had sometime ago the same issue. make sure that your ssh key doesn't have password and use not common user account (e.g. better to user account called jenkins or so).

check following article http://fourkitchens.com/blog/2011/09/20/trigger-jenkins-builds-pushing-github

Redis: How to access Redis log file

The log file will be where the configuration file (usually /etc/redis/redis.conf) says it is :)

By default, logfile stdout which probably isn't what you are looking for. If redis is running daemonized, then that log configuration means logs will be sent to /dev/null, i.e. discarded.

Summary: set logfile /path/to/my/log/file.log in your config and redis logs will be written to that file.

How to dismiss keyboard for UITextView with return key?

Using navigation controller to host a bar to dismiss the keyboard:

in the .h file:

UIBarButtonItem* dismissKeyboardButton;

in the .m file:

- (void)viewDidLoad {
    dismissKeyboardButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(dismissKeyboard)];
}

-(void)textViewDidBeginEditing:(UITextView *)textView {
    self.navigationItem.rightBarButtonItem = dismissKeyboardButton;
}

-(void)textFieldDidBeginEditing:(UITextField *)textField {
    self.navigationItem.rightBarButtonItem = dismissKeyboardButton;
}

-(void)dismissKeyboard {
    [self.textField resignFirstResponder];
    [self.textView resignFirstResponder];
    //or replace this with your regular right button
    self.navigationItem.rightBarButtonItem = nil;
}

Disabling browser caching for all browsers from ASP.NET

See also How to prevent google chrome from caching my inputs, esp hidden ones when user click back? without which Chrome might reload but preserve the previous content of <input> elements -- in other words, use autocomplete="off".

NodeJS - Error installing with NPM

As commented below you may not need to install VS on windows, check this out

https://github.com/nodejs/node-gyp/issues/629#issuecomment-153196245

UPDATED 02/2016

Some npm plugins need node-gyp to be installed.

However, node-gyp has it's own dependencies (from the github page):

enter image description here

UPDATED 09/2016

If you're using Windows you can now install all node-gyp dependencies with single command (NOTE: Run As Admin in Windows PowerShell):

 $ npm install --global --production windows-build-tools

and then install the package

 $ npm install --global node-gyp

UPDATED 06/2018

https://github.com/nodejs/node-gyp/issues/809#issuecomment-155019383

Delete your $HOME/.node-gyp directory and try again.

See full documentation here: node-gyp

Can an abstract class have a constructor?

In order to achieve constructor chaining, the abstract class will have a constructor. The compiler keeps Super() statement inside the subclass constructor, which will call the superclass constructor. If there were no constructors for abstract classes then java rules are violated and we can't achieve constructor chaining.

How to focus on a form input text field on page load using jQuery?

Think about your user interface before you do this. I assume (though none of the answers has said so) that you'll be doing this when the document loads using jQuery's ready() function. If a user has already focussed on a different element before the document has loaded (which is perfectly possible) then it's extremely irritating for them to have the focus stolen away.

You could check for this by adding onfocus attributes in each of your <input> elements to record whether the user has already focussed on a form field and then not stealing the focus if they have:

var anyFieldReceivedFocus = false;

function fieldReceivedFocus() {
    anyFieldReceivedFocus = true;
}

function focusFirstField() {
    if (!anyFieldReceivedFocus) {
        // Do jQuery focus stuff
    }
}


<input type="text" onfocus="fieldReceivedFocus()" name="one">
<input type="text" onfocus="fieldReceivedFocus()" name="two">

How do I create a datetime in Python from milliseconds?

Converting millis to datetime (UTC):

import datetime
time_in_millis = 1596542285000
dt = datetime.datetime.fromtimestamp(time_in_millis / 1000.0, tz=datetime.timezone.utc)

Converting datetime to string following the RFC3339 standard (used by Open API specification):

from rfc3339 import rfc3339
converted_to_str = rfc3339(dt, utc=True, use_system_timezone=False)
# 2020-08-04T11:58:05Z

Storing query results into a variable and modifying it inside a Stored Procedure

Yup, this is possible of course. Here are several examples.

-- one way to do this
DECLARE @Cnt int

SELECT @Cnt = COUNT(SomeColumn)
FROM TableName
GROUP BY SomeColumn

-- another way to do the same thing
DECLARE @StreetName nvarchar(100)
SET @StreetName = (SELECT Street_Name from Streets where Street_ID = 123)

-- Assign values to several variables at once
DECLARE @val1 nvarchar(20)
DECLARE @val2 int
DECLARE @val3 datetime
DECLARE @val4 uniqueidentifier
DECLARE @val5 double

SELECT @val1 = TextColumn,
@val2 = IntColumn,
@val3 = DateColumn,
@val4 = GuidColumn,
@val5 = DoubleColumn
FROM SomeTable

Elegant Python function to convert CamelCase to snake_case?

Take a look at the excellent Schematics lib

https://github.com/schematics/schematics

It allows you to created typed data structures that can serialize/deserialize from python to Javascript flavour, eg:

class MapPrice(Model):
    price_before_vat = DecimalType(serialized_name='priceBeforeVat')
    vat_rate = DecimalType(serialized_name='vatRate')
    vat = DecimalType()
    total_price = DecimalType(serialized_name='totalPrice')

How can I set the color of a selected row in DataGrid

As an extention to @Seb Kade's answer, you can fully control the colours of the selected and unselected rows using the following Style:

<Style TargetType="{x:Type DataGridRow}">
    <Style.Resources>
        <SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="Transparent" />
        <SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="Transparent" />
        <SolidColorBrush x:Key="{x:Static SystemColors.HighlightTextBrushKey}" Color="Black" />
        <SolidColorBrush x:Key="{x:Static SystemColors.ControlTextBrushKey}" Color="Black" />
    </Style.Resources>
</Style>

You can of course enter whichever colours you prefer. This Style will also work for other collection items such as ListBoxItems (if you replace TargetType="{x:Type DataGridRow}" with TargetType="{x:Type ListBoxItem}" for instance).

Breaking to a new line with inline-block?

You can try with:

    display: inline-table;

For me it works fine.

Render HTML to an image

Use this code, it will surely work:

_x000D_
_x000D_
<script type="text/javascript">_x000D_
 $(document).ready(function () {_x000D_
  setTimeout(function(){_x000D_
   downloadImage();_x000D_
  },1000)_x000D_
 });_x000D_
 _x000D_
 function downloadImage(){_x000D_
  html2canvas(document.querySelector("#dvContainer")).then(canvas => {_x000D_
  a = document.createElement('a'); _x000D_
  document.body.appendChild(a); _x000D_
  a.download = "test.png"; _x000D_
  a.href =  canvas.toDataURL();_x000D_
  a.click();_x000D_
 });  _x000D_
 }_x000D_
</script>
_x000D_
_x000D_
_x000D_

Just do not forget to include Html2CanvasJS file in your program. https://html2canvas.hertzen.com/dist/html2canvas.js

Which version of Python do I have installed?

When I open Python (command line) the first thing it tells me is the version.

What uses are there for "placement new"?

I've used it in real-time programming. We typically don't want to perform any dynamic allocation (or deallocation) after the system starts up, because there's no guarantee how long that is going to take.

What I can do is preallocate a large chunk of memory (large enough to hold any amount of whatever that the class may require). Then, once I figure out at runtime how to construct the things, placement new can be used to construct objects right where I want them. One situation I know I used it in was to help create a heterogeneous circular buffer.

It's certainly not for the faint of heart, but that's why they make the syntax for it kinda gnarly.

#1273 – Unknown collation: ‘utf8mb4_unicode_520_ci’

You can solve this by finding

ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_520_ci;

in your .sql file, and swapping it with

ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_general_ci;

Get dates from a week number in T-SQL

Another way to do it:

declare @week_number int;
declare @start_weekday int = 0 -- Monday
declare @end_weekday int = 6 -- next Sunday

select @week_number = datediff(week, 0, getdate())

select 
    dateadd(week, @week_number, @start_weekday) as WEEK_FIRST_DAY, 
    dateadd(week, @week_number, @end_weekday) as WEEK_LAST_DAY

Explanation:

  • @week_number is computed based on the initial calendar date '1900-01-01'. Replace getdate() by whatever date you want.
  • @start_weekday is 0 if Monday. If Sunday, then declare it as -1
  • @end_weekday is 6 if next Sunday. If Saturday, then declare it as 5
  • Then dateadd function, will add the given number of weeks and the given number of days to the initial calendar date '1900-01-01'.

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

using (FileStream fs = new FileStream("sample.pdf", FileMode.Open, FileAccess.Read))
            {
                byte[] bytes = new byte[fs.Length];
                int numBytesToRead = (int)fs.Length;
                int numBytesRead = 0;
                while (numBytesToRead > 0)
                {
                    // Read may return anything from 0 to numBytesToRead.
                    int n = fs.Read(bytes, numBytesRead, numBytesToRead);

                    // Break when the end of the file is reached.
                    if (n == 0)
                    {
                        break;
                    }

                    numBytesRead += n;
                    numBytesToRead -= n;
                }
                numBytesToRead = bytes.Length;
}

How can I open the interactive matplotlib window in IPython notebook?

I'm using ipython in "jupyter QTConsole" from Anaconda at www.continuum.io/downloads on 5/28/20117.

Here's an example to flip back and forth between a separate window and an inline plot mode using ipython magic.

>>> import matplotlib.pyplot as plt

# data to plot
>>> x1 = [x for x in range(20)]

# Show in separate window
>>> %matplotlib
>>> plt.plot(x1)
>>> plt.close() 

# Show in console window
>>> %matplotlib inline
>>> plt.plot(x1)
>>> plt.close() 

# Show in separate window
>>> %matplotlib
>>> plt.plot(x1)
>>> plt.close() 

# Show in console window
>>> %matplotlib inline
>>> plt.plot(x1)
>>> plt.close() 

# Note: the %matplotlib magic above causes:
#      plt.plot(...) 
# to implicitly include a:
#      plt.show()
# after the command.
#
# (Not sure how to turn off this behavior
# so that it matches behavior without using %matplotlib magic...)
# but its ok for interactive work...

count of entries in data frame in R

DPLYR makes this really easy.

x<-santa%>%
   count(Believe)

If you wanted to count by a group; for instance, how many males v females believe, just add a group_by:

x<-santa%>%
   group_by(Gender)%>%
   count(Believe)

UIButton title text color

swift 5 version:

By using default inbuilt color:

  1. button.setTitleColor(UIColor.green, for: .normal)

OR

You can use your custom color by using RGB method:

  1. button.setTitleColor(UIColor(displayP3Red: 0.0/255.0, green: 180.0/255.0, blue: 2.0/255.0, alpha: 1.0), for: .normal)

Module 'tensorflow' has no attribute 'contrib'

tf.contrib has moved out of TF starting TF 2.0 alpha.
Take a look at these tf 2.0 release notes https://github.com/tensorflow/tensorflow/releases/tag/v2.0.0-alpha0
You can upgrade your TF 1.x code to TF 2.x using the tf_upgrade_v2 script https://www.tensorflow.org/alpha/guide/upgrade

Is it possible to use "return" in stored procedure?

CREATE PROCEDURE pr_emp(dept_id IN NUMBER,vv_ename out varchar2  )
 AS
 v_ename emp%rowtype;
CURSOR c_emp IS
    SELECT ename
    FROM emp where deptno=dept_id;
 BEGIN
     OPEN c;
     loop
        FETCH c_emp INTO v_ename;
        return v_ename; 
        vv_ename := v_ename 
        exit when c_emp%notfound;
     end loop;
     CLOSE c_emp;


 END pr_emp;

Static Block in Java

Static blocks are used for initializaing the code and will be executed when JVM loads the class.Refer to the below link which gives the detailed explanation. http://www.jusfortechies.com/java/core-java/static-blocks.php

How to save S3 object to a file using boto3

boto3 now has a nicer interface than the client:

resource = boto3.resource('s3')
my_bucket = resource.Bucket('MyBucket')
my_bucket.download_file(key, local_filename)

This by itself isn't tremendously better than the client in the accepted answer (although the docs say that it does a better job retrying uploads and downloads on failure) but considering that resources are generally more ergonomic (for example, the s3 bucket and object resources are nicer than the client methods) this does allow you to stay at the resource layer without having to drop down.

Resources generally can be created in the same way as clients, and they take all or most of the same arguments and just forward them to their internal clients.

How to show the last queries executed on MySQL?

You can look at the following in linux

cd /root

ls -al

vi .mysql_history It may help

z-index not working with fixed positioning

I was building a nav menu. I have overflow: hidden in my nav's css which hid everything. I thought it was a z-index problem, but really I was hiding everything outside my nav.

What does this GCC error "... relocation truncated to fit..." mean?

On Cygwin -mcmodel=medium is already default and doesn't help. To me adding -Wl,--image-base -Wl,0x10000000 to GCC linker did fixed the error.

Get to UIViewController from UIView?

If you aren't going to upload this to the App Store, you can also use a private method of UIView.

@interface UIView(Private)
- (UIViewController *)_viewControllerForAncestor;
@end

// Later in the code
UIViewController *vc = [myView _viewControllerForAncestor];

Should I use != or <> for not equal in T-SQL?

They are both accepted in T-SQL. However, it seems that using <> works a lot faster than !=. I just ran a complex query that was using !=, and it took about 16 seconds on average to run. I changed those to <> and the query now takes about 4 seconds on average to run. That's a huge improvement!

do <something> N times (declarative syntax)

If you can't use Underscorejs, you can implement it yourself. By attaching new methods to the Number and String prototypes, you could do it like this (using ES6 arrow functions):

// With String
"5".times( (i) => console.log("number "+i) );

// With number variable
var five = 5;
five.times( (i) => console.log("number "+i) );

// With number literal (parentheses required)
(5).times( (i) => console.log("number "+i) );

You simply have to create a function expression (of whatever name) and assign it to whatever property name (on the prototypes) you would like to access it as:

var timesFunction = function(callback) {
  if (typeof callback !== "function" ) {
    throw new TypeError("Callback is not a function");
  } else if( isNaN(parseInt(Number(this.valueOf()))) ) {
    throw new TypeError("Object is not a valid number");
  }
  for (var i = 0; i < Number(this.valueOf()); i++) {
    callback(i);
  }
};

String.prototype.times = timesFunction;
Number.prototype.times = timesFunction;

How to enable Auto Logon User Authentication for Google Chrome

Chrome did change their menus since this question was asked. This solution was tested with Chrome 47.0.2526.73 to 72.0.3626.109.

If you are using Chrome right now, you can check your version with : chrome://version

  1. Goto: chrome://settings

  1. Scroll down to the bottom of the page and click on "Advanced" to show more settings.

OLDER VERSIONS:

Scroll down to the bottom of the page and click on "Show advanced settings..." to show more settings.

  1. In the "System" section, click on "Open proxy settings".

OLDER VERSIONS:

In the "Network" section, click on "Change proxy settings...".

  1. Click on the "Security" tab, then select "Local intranet" icon and click on "Sites" button.

  1. Click on "Advanced" button.

  1. Insert your intranet local address and click on the "Add" button.

  1. Close all windows.

That's it.

Substring with reverse index

The substring method allows you to specify start and end index:

var str = "xxx_456";
var subStr = str.substring(str.length - 3, str.length);

increment date by one month

//ECHO MONTHS BETWEEN TWO TIMESTAMPS
$my_earliest_timestamp = 1532095200;
$my_latest_timestamp = 1554991200;

echo '<pre>';
echo "Earliest timestamp: ". date('c',$my_earliest_timestamp) ."\r\n";
echo "Latest timestamp: " .date('c',$my_latest_timestamp) ."\r\n\r\n";

echo "Month start of earliest timestamp: ". date('c',strtotime('first day of '. date('F Y',$my_earliest_timestamp))) ."\r\n";
echo "Month start of latest timestamp: " .date('c',strtotime('first day of '. date('F Y',$my_latest_timestamp))) ."\r\n\r\n";

echo "Month end of earliest timestamp: ". date('c',strtotime('last day of '. date('F Y',$my_earliest_timestamp)) + 86399) ."\r\n";
echo "Month end of latest timestamp: " .date('c',strtotime('last day of '. date('F Y',$my_latest_timestamp)) + 86399) ."\r\n\r\n";

$sMonth = strtotime('first day of '. date('F Y',$my_earliest_timestamp));
$eMonth = strtotime('last day of '. date('F Y',$my_earliest_timestamp)) + 86399;
$xMonth = strtotime('+1 month', strtotime('first day of '. date('F Y',$my_latest_timestamp)));

while ($eMonth < $xMonth) {
    echo "Things from ". date('Y-m-d',$sMonth) ." to ". date('Y-m-d',$eMonth) ."\r\n\r\n";
    $sMonth = $eMonth + 1; //add 1 second to bring forward last date into first second of next month.
    $eMonth = strtotime('last day of '. date('F Y',$sMonth)) + 86399;
}

Converting a date string to a DateTime object using Joda Time library

tl;dr

java.time.LocalDateTime.parse( 
    "04/02/2011 20:27:05" , 
    DateTimeFormatter.ofPattern( "dd/MM/uuuu HH:mm:ss" )
)

java.time

The modern approach uses the java.time classes that supplant the venerable Joda-Time project.

Parse as a LocalDateTime as your input lacks any indicator of time zone or offset-from-UTC.

String input = "04/02/2011 20:27:05" ;
DateTimeFormatter f = DateTimeFormatter.ofPattern( "dd/MM/uuuu HH:mm:ss" ) ;
LocalDateTime ldt = LocalDateTime.parse( input , f ) ;

ldt.toString(): 2011-02-04T20:27:05

Tip: Where possible, use the standard ISO 8601 formats when exchanging date-time values as text rather than format seen here. Conveniently, the java.time classes use the standard formats when parsing/generating strings.


About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

Where to obtain the java.time classes?

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

Join two sql queries

Some DBMSs support the FROM (SELECT ...) AS alias_name syntax.

Think of your two original queries as temporary tables. You can query them like so:

SELECT t1.Activity, t1."Total Amount 2009", t2."Total Amount 2008"
FROM (query1) as t1, (query2) as t2
WHERE t1.Activity = t2.Activity

How Do I Convert an Integer to a String in Excel VBA?

Another way to do it is to splice two parsed sections of the numerical value together:

Cells(RowNum, ColumnNum).Value = Mid(varNumber,1,1) & Mid(varNumber,2,Len(varNumber))

I have found better success with this than CStr() because CStr() doesn't seem to convert decimal numbers that came from variants in my experience.

ADB not responding. You can wait more,or kill "adb.exe" process manually and click 'Restart'

I had the same problem. I have restarted ADB in any possible way, I have killed the process and restarted the PC with no results.

Then I found this plugin. Just download and install it in your Android Studio IDE. Under Tools -> Android you have a menu ADB Idea. Here you can kill, start, restart, clean ADB.

Dismissing a Presented View Controller

If you are using modal use view dismiss.

[self dismissViewControllerAnimated:NO completion:nil];

Select All Rows Using Entity Framework

Entity Framework has one beautiful thing for it, like :

var users = context.Users; 

This will select all rows in Table User, then you can use your .ToList() etc.


For newbies to Entity Framework, it is like :

PortalEntities context = new PortalEntities();
var users = context.Users;

This will select all rows in Table User

Check if a parameter is null or empty in a stored procedure

What about combining coalesce and nullif?

SET @PreviousStartDate = coalesce(nullif(@PreviousStartDate, ''), '01/01/2010')

Configuring Git over SSH to login once

I tried all of these suggestions and more, just so I could git clone from my AWS instance. Nothing worked. I finally cheated out of desperation: I copied the contents of id_rsa.pub on my local machine and appended it to ~/.ssh/known_hosts on my AWS instance.

Multiple conditions in a C 'for' loop

Completing Mr. Crocker's answer, be careful about ++ or -- operators or I don't know maybe other operators. They can affect the loop. for example I saw a code similar to this one in a course:

for(int i=0; i++*i<-1, i<3; printf(" %d", i));

The result would be $ 1 2$. So the first statement has affected the loop while the outcome of the following is lots of zeros.

for(int i=0; i<3; printf(" %d", i));

The remote end hung up unexpectedly while git cloning

I had a similar problem, but with a bamboo job. Bamboo was failing doing a local clone (local but over an SSH proxy) of a cached repository, I deleted the cache and after that it worked, but any time it tries to clone from the local cache there is a failure. Seems like a problem with bamboo's version of the SSH proxy not git per se.

Angular and Typescript: Can't find names - Error: cannot find name

add typing.d.ts in main folder of the application and over there declare the varible which you want to use every time

declare var System: any;
declare var require: any;

after declaring this in typing.d.ts, error for require will not come in the application..

How to get time (hour, minute, second) in Swift 3 using NSDate?

let date = Date()       
let units: Set<Calendar.Component> = [.hour, .day, .month, .year]
let comps = Calendar.current.dateComponents(units, from: date)

How to end a session in ExpressJS

use,

delete req.session.yoursessionname;

Javascript counting number of objects in object

Try Demo Here

var list ={}; var count= Object.keys(list).length;

How do I merge changes to a single file, rather than merging commits?

I came across the same problem. To be precise, I have two branches A and B with the same files but a different programming interface in some files. Now the methods of file f, which is independent of the interface differences in the two branches, were changed in branch B, but the change is important for both branches. Thus, I need to merge just file f of branch B into file f of branch A.

A simple command already solved the problem for me if I assume that all changes are committed in both branches A and B:

git checkout A

git checkout --patch B f

The first command switches into branch A, into where I want to merge B's version of the file f. The second command patches the file f with f of HEAD of B. You may even accept/discard single parts of the patch. Instead of B you can specify any commit here, it does not have to be HEAD.

Community edit: If the file f on B does not exist on A yet, then omit the --patch option. Otherwise, you'll get a "No Change." message.

Bootstrap 4, how to make a col have a height of 100%?

Set display: table for parent div and display: table-cell for children divs

HTML :

<div class="container-fluid">
  <div class="row justify-content-center display-as-table">

    <div class="col-4 hidden-md-down" id="yellow">
      XXXX<br />
      XXXX<br />
      XXXX<br />
      XXXX<br />
      XXXX<br />
      XXXX<br />vv
      XXXX<br />
    </div>

    <div class="col-10 col-sm-10 col-md-10 col-lg-8 col-xl-8" id="red">
      Form Goes Here
    </div>
  </div>
</div>

CSS:

#yellow {
  height: 100%;
  background: yellow;
  width: 50%;
}
#red {background: red}

.container-fluid {bacgkround: #ccc}

/* this is the part make equal height */
.display-as-table {display: table; width: 100%;}
.display-as-table > div {display: table-cell; float: none;}

How to append one DataTable to another DataTable

The datatype in the same columns name must be equals.

dataTable1.Merge(dataTable2);

After that the result is:

dataTable1 = dataTable1 + dataTable2

AngularJS How to dynamically add HTML and bind to controller

There is a another way also

  1. step 1: create a sample.html file
  2. step 2: create a div tag with some id=loadhtml Eg : <div id="loadhtml"></div>
  3. step 3: in Any Controller

        var htmlcontent = $('#loadhtml ');
        htmlcontent.load('/Pages/Common/contact.html')
        $compile(htmlcontent.contents())($scope);
    

This Will Load a html page in Current page

json.net has key method?

JObject.ContainsKey(string propertyName) has been made as public method in 11.0.1 release

Documentation - https://www.newtonsoft.com/json/help/html/M_Newtonsoft_Json_Linq_JObject_ContainsKey.htm

Why GDB jumps unpredictably between lines and prints variables as "<value optimized out>"?

Declare found as "volatile". This should tell the compiler to NOT optimize it out.

volatile int found = 0;

Convert Unix timestamp into human readable date using MySQL

Easy and simple way:

select from_unixtime(column_name, '%Y-%m-%d') from table_name

How to SSH into Docker?

Create docker image with openssh-server preinstalled:

Dockerfile

FROM ubuntu:16.04

RUN apt-get update && apt-get install -y openssh-server
RUN mkdir /var/run/sshd
RUN echo 'root:screencast' | chpasswd
RUN sed -i 's/PermitRootLogin prohibit-password/PermitRootLogin yes/' /etc/ssh/sshd_config

# SSH login fix. Otherwise user is kicked off after login
RUN sed 's@session\s*required\s*pam_loginuid.so@session optional pam_loginuid.so@g' -i /etc/pam.d/sshd

ENV NOTVISIBLE "in users profile"
RUN echo "export VISIBLE=now" >> /etc/profile

EXPOSE 22
CMD ["/usr/sbin/sshd", "-D"]

Build the image using:

$ docker build -t eg_sshd .

Run a test_sshd container:

$ docker run -d -P --name test_sshd eg_sshd
$ docker port test_sshd 22

0.0.0.0:49154

Ssh to your container:

$ ssh [email protected] -p 49154
# The password is ``screencast``.
root@f38c87f2a42d:/#

Source: https://docs.docker.com/engine/examples/running_ssh_service/#build-an-eg_sshd-image

How do I join two SQLite tables in my Android application?

In addition to @pawelzieba's answer, which definitely is correct, to join two tables, while you can use an INNER JOIN like this

SELECT * FROM expense INNER JOIN refuel
ON exp_id = expense_id
WHERE refuel_id = 1

via raw query like this -

String rawQuery = "SELECT * FROM " + RefuelTable.TABLE_NAME + " INNER JOIN " + ExpenseTable.TABLE_NAME
        + " ON " + RefuelTable.EXP_ID + " = " + ExpenseTable.ID
        + " WHERE " + RefuelTable.ID + " = " +  id;
Cursor c = db.rawQuery(
        rawQuery,
        null
);

because of SQLite's backward compatible support of the primitive way of querying, we turn that command into this -

SELECT *
FROM expense, refuel
WHERE exp_id = expense_id AND refuel_id = 1

and hence be able to take advanatage of the SQLiteDatabase.query() helper method

Cursor c = db.query(
        RefuelTable.TABLE_NAME + " , " + ExpenseTable.TABLE_NAME,
        Utils.concat(RefuelTable.PROJECTION, ExpenseTable.PROJECTION),
        RefuelTable.EXP_ID + " = " + ExpenseTable.ID + " AND " + RefuelTable.ID + " = " +  id,
        null,
        null,
        null,
        null
);

For a detailed blog post check this http://blog.championswimmer.in/2015/12/doing-a-table-join-in-android-without-using-rawquery

How to refresh an IFrame using Javascript?

If you use hash paths (like mywebsite.com/#/my/url) which might not refresh frames on switching hash:

<script>
    window.onhashchange = function () {
        window.setTimeout(function () {
            let frame = document.getElementById('myFrame');
            if (frame !== null) {frame.replaceWith(frame);}
        }, 1000);
    }
</script>

Unfortunately, if you don't use the timeout JS may try to replace the frame before the page has finished loading the content (thus loading the old content). I'm not sure of the workaround yet.

Paused in debugger in chrome?

Threads > switch "Main" to "app"

In the "Threads" section I changed the context from "Main" > to "app". The "app" should have a blue arrow aside.

How do I add the Java API documentation to Eclipse?

Ensure "Preferences" -> "Java" -> "Editor" -> "Hovers" -> "Combined Hover" is checked.

How to use Scanner to accept only valid int as input

What you could do is also to take the next token as a String, converts this string to a char array and test that each character in the array is a digit.

I think that's correct, if you don't want to deal with the exceptions.

Force an SVN checkout command to overwrite current files

This can be done pretty easily. All I did was move the existing directory, not under version control, to a temporary directory. Then I checked out the SVN version to my correct directory name, copied the files from the temporary directory into the SVN directory, and reverted the files in the SVN directory. If that does not make sense there is an example below:

/usr/local/www

mv www temp_www
svn co http://www.yourrepo.com/therepo www
cp -pR ./temp_www/* ./www
svn revert -R ./www/*
svn update

I hope this helps and am not sure why just a simple SVN update did not change the files back?

How can I use jQuery to make an input readonly?

Maybe use atribute disabled:

<input disabled="disabled" id="fieldName" name="fieldName" type="text" class="text_box" />

Or just use label tag: ;)

<label>

How to automatically add user account AND password with a Bash script?

From IBM (https://www.ibm.com/support/knowledgecenter/ssw_aix_61/com.ibm.aix.cmds1/chpasswd.htm):

Create a text file, say text.txt and populate it with user:password pairs as follows:

user1:password1
user2:password2
...
usern:passwordn

Save the text.txt file, and run

cat text.txt | chpassword

That's it. The solution is (a) scalable and (b) does not involve printing passwords on the command line.

How to use conditional breakpoint in Eclipse?

Put your breakpoint. Right-click the breakpoint image on the margin and choose Breakpoint Properties:

enter image description here

Configure condition as you see fit:

enter image description here

Wait for async task to finish

How about calling a function from within your callback instead of returning a value in sync_call()?

function sync_call(input) {
    var value;

    // Assume the async call always succeed
    async_call(input, function(result) {
        value = result;
        use_value(value);
    } );
}

Passing data from controller to view in Laravel

public function showstudents() {
     $students = DB::table('student')->get();
     return (View::make("user/regprofile", compact('student')));
}

How to get a file directory path from file path?

You could try something like this using approach for How to find the last field using 'cut':

Explanation

  • rev reverses /home/user/mydir/file_name.c to be c.eman_elif/ridym/resu/emoh/
  • cut uses dot (ie /) as the delimiter, and chooses the first field, which is c.eman_elif
  • lastly, we reverse it again to get file_name.c
$ VAR="/home/user/mydir/file_name.c"
$ echo $VAR | rev | cut -f1 -d"/" | rev
file_name.c

javac not working in windows command prompt

When i tried to make the .java to .class the command Javac didnt work. I got it working by going to C:\Program Files (x86)\Java\jdk1.7.0_04\bin and when i was on that directory I typed Javac.exe C\Test\test.java and it made the class with that tactic. Try that out.

Excel Reference To Current Cell

Full credit to the top answer by @rick-teachey, but you can extend that approach to work with Conditional Formatting. So that this answer is complete, I will duplicate Rick's answer in summary form and then extend it:

  1. Select cell A1 in any worksheet.
  2. Create a Named Range called THIS and set the Refers to: to =!A1.

Attempting to use THIS in Conditional Formatting formulas will result in the error:

You may not use references to other workbooks for Conditional Formatting criteria

If you want THIS to work in Conditional Formatting formulas:

  1. Create another Named Range called THIS_CF and set the Refers to: to =THIS.

You can now use THIS_CF to refer to the current cell in Conditional Formatting formulas.

You can also use this approach to create other relative Named Ranges, such as THIS_COLUMN, THIS_ROW, ROW_ABOVE, COLUMN_LEFT, etc.

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

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

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

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

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

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

Getting current directory in .NET web application

Use this code:

 HttpContext.Current.Server.MapPath("~")

Detailed Reference:

Server.MapPath specifies the relative or virtual path to map to a physical directory.

  • Server.MapPath(".") returns the current physical directory of the file (e.g. aspx) being executed
  • Server.MapPath("..") returns the parent directory
  • Server.MapPath("~") returns the physical path to the root of the application
  • Server.MapPath("/") returns the physical path to the root of the domain name (is not necessarily the same as the root of the application)

An example:

Let's say you pointed a web site application (http://www.example.com/) to

C:\Inetpub\wwwroot

and installed your shop application (sub web as virtual directory in IIS, marked as application) in

D:\WebApps\shop

For example, if you call Server.MapPath in following request:

http://www.example.com/shop/products/GetProduct.aspx?id=2342

then:

Server.MapPath(".") returns D:\WebApps\shop\products
Server.MapPath("..") returns D:\WebApps\shop
Server.MapPath("~") returns D:\WebApps\shop
Server.MapPath("/") returns C:\Inetpub\wwwroot
Server.MapPath("/shop") returns D:\WebApps\shop

If Path starts with either a forward (/) or backward slash (), the MapPath method returns a path as if Path were a full, virtual path.

If Path doesn't start with a slash, the MapPath method returns a path relative to the directory of the request being processed.

Note: in C#, @ is the verbatim literal string operator meaning that the string should be used "as is" and not be processed for escape sequences.

Footnotes

Server.MapPath(null) and Server.MapPath("") will produce this effect too.

Laravel Eloquent compare date from datetime field

You can get the all record of the date '2016-07-14' by using it

 whereDate('date','=','2016-07-14')

Or use the another code for dynamic date

whereDate('date',$date)

What does the "$" sign mean in jQuery or JavaScript?

The $ symbol simply invokes the jQuery library's selector functionality. So $("#Text") returns the jQuery object for the Text div which can then be modified.

How to get the current working directory using python 3?

It seems that IDLE changes its current working dir to location of the script that is executed, while when running the script using cmd doesn't do that and it leaves CWD as it is.

To change current working dir to the one containing your script you can use:

import os
os.chdir(os.path.dirname(__file__))
print(os.getcwd())

The __file__ variable is available only if you execute script from file, and it contains path to the file. More on it here: Python __file__ attribute absolute or relative?

Windows service start failure: Cannot start service from the command line or debugger

To install Open CMD and type in {YourServiceName} -i once its installed type in NET START {YourserviceName} to start your service

to uninstall

To uninstall Open CMD and type in NET STOP {YourserviceName} once stopped type in {YourServiceName} -u and it should be uninstalled

XMLHttpRequest cannot load an URL with jQuery

Fiddle with 3 working solutions in action.

Given an external JSON:

myurl = 'http://wikidata.org/w/api.php?action=wbgetentities&sites=frwiki&titles=France&languages=zh-hans|zh-hant|fr&props=sitelinks|labels|aliases|descriptions&format=json'

Solution 1: $.ajax() + jsonp:

$.ajax({
  dataType: "jsonp",
  url: myurl ,
  }).done(function ( data ) {
  // do my stuff
});

Solution 2: $.ajax()+json+&calback=?:

$.ajax({
  dataType: "json",
  url: myurl + '&callback=?',
  }).done(function ( data ) {
  // do my stuff
});

Solution 3: $.getJSON()+calback=?:

$.getJSON( myurl + '&callback=?', function(data) {
  // do my stuff
});

Documentations: http://api.jquery.com/jQuery.ajax/ , http://api.jquery.com/jQuery.getJSON/

How to decode JWT Token?

Using .net core jwt packages, the Claims are available:

[Route("api/[controller]")]
[ApiController]
[Authorize(Policy = "Bearer")]
public class AbstractController: ControllerBase
{
    protected string UserId()
    {
        var principal = HttpContext.User;
        if (principal?.Claims != null)
        {
            foreach (var claim in principal.Claims)
            {
               log.Debug($"CLAIM TYPE: {claim.Type}; CLAIM VALUE: {claim.Value}");
            }

        }
        return principal?.Claims?.SingleOrDefault(p => p.Type == "username")?.Value;
    }
}

Qt. get part of QString

If you do not need to modify the substring, then you can use QStringRef. The QStringRef class is a read only wrapper around an existing QString that references a substring within the existing string. This gives much better performance than creating a new QString object to contain the sub-string. E.g.

QString myString("This is a string");
QStringRef subString(&myString, 5, 2); // subString contains "is"

If you do need to modify the substring, then left(), mid() and right() will do what you need...

QString myString("This is a string");
QString subString = myString.mid(5,2); // subString contains "is"
subString.append("n't"); // subString contains "isn't"

Laravel: Validation unique on update

I read the previous post, but none approach the real problem. We need use the rule unique to apply on add and edit case. I use this rule on edit and add case and work fine.

In my solution i use rule function from Request Class.

  1. I sent id over hidden input form field on edit form.
  2. On the Rule function, we find by unique column and get the record.
  3. Now evaluate the situation. If exist record and id are equal the unique must be not activate (that's mean edit record).

On the code:

public function rules()
    {
        //
        $user = User::where('email', $this->email)->first();
        //
        $this->id = isset($this->id) ? $this->id : null;
        $emailRule = (($user != null) && ($user->id == $this->id)) ? 'required|email:rfc,dns|max:255' : 'required|unique:users|email:rfc,dns|max:255';
        //        
        return [
            //
            'email'            =>  $emailRule,                
            //
        ];
        //


    }

Python - Locating the position of a regex match in a string?

You could use .find("is"), it would return position of "is" in the string

or use .start() from re

>>> re.search("is", String).start()
2

Actually its match "is" from "This"

If you need to match per word, you should use \b before and after "is", \b is the word boundary.

>>> re.search(r"\bis\b", String).start()
5
>>>

for more info about python regular expressions, docs here

How do I get the directory that a program is running from?

I know it is very late at the day to throw an answer at this one but I found that none of the answers were as useful to me as my own solution. A very simple way to get the path from your CWD to your bin folder is like this:

int main(int argc, char* argv[])
{
    std::string argv_str(argv[0]);
    std::string base = argv_str.substr(0, argv_str.find_last_of("/"));
}

You can now just use this as a base for your relative path. So for example I have this directory structure:

main
  ----> test
  ----> src
  ----> bin

and I want to compile my source code to bin and write a log to test I can just add this line to my code.

std::string pathToWrite = base + "/../test/test.log";

I have tried this approach on Linux using full path, alias etc. and it works just fine.

NOTE:

If you are on windows you should use a '\' as the file separator not '/'. You will have to escape this too for example:

std::string base = argv[0].substr(0, argv[0].find_last_of("\\"));

I think this should work but haven't tested, so comment would be appreciated if it works or a fix if not.

what is Ljava.lang.String;@

The method works if you provide an array. The output of

String[] helloWorld = {"Hello", "World"};
System.out.println(helloWorld);
System.out.println(Arrays.toString(helloWorld));

is

[Ljava.lang.String;@45a877
[Hello, World]

(the number after @ is almost always different)

Please tell us the return type of Employee.getSelectCancel()

checking if a number is divisible by 6 PHP

Why don't you use the Modulus Operator?

Try this:

while ($s % 6 != 0) $s++;

Or is this what you meant?

<?

 $s= <some_number>;
 $k= $s % 6;

 if($k !=0)    $s=$s+6-$k;
?>

Auto-indent in Notepad++

Notepad++ will only auto-insert subsequent indents if you manually indent the first line in a block; otherwise you can re-indent your code after the fact using TextFX > TextFX Edit > Reindent C++ code.

How to set Linux environment variables with Ansible

For persistently setting environment variables, you can use one of the existing roles over at Ansible Galaxy. I recommend weareinteractive.environment.

Using ansible-galaxy:

$ ansible-galaxy install weareinteractive.environment

Using requirements.yml:

- src: franklinkim.environment

Then in your playbook:

- hosts: all
  sudo: yes
  roles:
    - role: franklinkim.environment
      environment_config:
        NODE_ENV: staging
        DATABASE_NAME: staging

Command /usr/bin/codesign failed with exit code 1

Steps to Fix this issue:

  1. Go to Key Chain Access.
    1. Select the i-Phone Developer certificate.
    2. Lock the Certificate.( Menu bar - Lock Button)
    3. Give the Machine Password.
    4. Unlock the Certificate.

Now clean and rebuild the project, this issue will resolve.

How to Concatenate Numbers and Strings to Format Numbers in T-SQL?

select 'abcd' + ltrim(str(1)) + ltrim(str(2))

How do I parallelize a simple Python loop?

Let's say we have an async function

async def work_async(self, student_name: str, code: str, loop):
"""
Some async function
"""
    # Do some async procesing    

That needs to be run on a large array. Some attributes are being passed to the program and some are used from property of dictionary element in the array.

async def process_students(self, student_name: str, loop):
    market = sys.argv[2]
    subjects = [...] #Some large array
    batchsize = 5
    for i in range(0, len(subjects), batchsize):
        batch = subjects[i:i+batchsize]
        await asyncio.gather(*(self.work_async(student_name,
                                           sub['Code'],
                                           loop)
                       for sub in batch))

How to load/edit/run/save text files (.py) into an IPython notebook cell?

EDIT: Starting from IPython 3 (now Jupyter project), the notebook has a text editor that can be used as a more convenient alternative to load/edit/save text files.

A text file can be loaded in a notebook cell with the magic command %load.

If you execute a cell containing:

%load filename.py

the content of filename.py will be loaded in the next cell. You can edit and execute it as usual.

To save the cell content back into a file add the cell-magic %%writefile filename.py at the beginning of the cell and run it. Beware that if a file with the same name already exists it will be silently overwritten.

To see the help for any magic command add a ?: like %load? or %%writefile?.

For general help on magic functions type "%magic" For a list of the available magic functions, use %lsmagic. For a description of any of them, type %magic_name?, e.g. '%cd?'.

See also: Magic functions from the official IPython docs.

What does "Error: object '<myvariable>' not found" mean?

Let's discuss why an "object not found" error can be thrown in R in addition to explaining what it means. What it means (to many) is obvious: the variable in question, at least according to the R interpreter, has not yet been defined, but if you see your object in your code there can be multiple reasons for why this is happening:

  1. check syntax of your declarations. If you mis-typed even one letter or used upper case instead of lower case in a later calling statement, then it won't match your original declaration and this error will occur.

  2. Are you getting this error in a notebook or markdown document? You may simply need to re-run an earlier cell that has your declarations before running the current cell where you are calling the variable.

  3. Are you trying to knit your R document and the variable works find when you run the cells but not when you knit the cells? If so - then you want to examine the snippet I am providing below for a possible side effect that triggers this error:

    {r sourceDataProb1, echo=F, eval=F} # some code here

The above snippet is from the beginning of an R markdown cell. If eval and echo are both set to False this can trigger an error when you try to knit the document. To clarify. I had a use case where I had left these flags as False because I thought i did not want my code echoed or its results to show in the markdown HTML I was generating. But since the variable was then used in later cells, this caused an error during knitting. Simple trial and error with T/F TRUE/FALSE flags can establish if this is the source of your error when it occurs in knitting an R markdown document from RStudio.

Lastly: did you remove the variable or clear it from memory after declaring it?

  • rm() removes the variable
  • hitting the broom icon in the evironment window of RStudio clearls everything in the current working environment
  • ls() can help you see what is active right now to look for a missing declaration.
  • exists("x") - as mentioned by another poster, can help you test a specific value in an environment with a very lengthy list of active variables

Using getline() with file input in C++

ifstream inFile;
string name, temp;
int age;

inFile.open("file.txt");

getline(inFile, name, ' '); // use ' ' as separator, default is '\n' (newline). Now name is "John".
getline(inFile, temp, ' '); // Now temp is "Smith"
name.append(1,' ');
name += temp;
inFile >> age; 

cout << name << endl;
cout << age << endl;  

inFile.close();    

How to see tomcat is running or not

Go to the start menu. Open up cmd (command prompt) and type in the following.

wmic process list brief | find /i "tomcat"

This would tell you if the tomcat is running or not.

HTML CSS Button Positioning

Use margins instead of line-height and then apply float to the buttons. By default they are displaying as inline-block, so when one is pushed down the hole line is pushed down with him. Float fixes this:

#header button {
    float:left;
}

Here's a working jsfidle.

Setting environment variables for accessing in PHP when using Apache

Something along the lines:

<VirtualHost hostname:80>
   ...
   SetEnv VARIABLE_NAME variable_value
   ...
</VirtualHost>

How to write std::string to file?

You're currently writing the binary data in the string-object to your file. This binary data will probably only consist of a pointer to the actual data, and an integer representing the length of the string.

If you want to write to a text file, the best way to do this would probably be with an ofstream, an "out-file-stream". It behaves exactly like std::cout, but the output is written to a file.

The following example reads one string from stdin, and then writes this string to the file output.txt.

#include <fstream>
#include <string>
#include <iostream>

int main()
{
    std::string input;
    std::cin >> input;
    std::ofstream out("output.txt");
    out << input;
    out.close();
    return 0;
}

Note that out.close() isn't strictly neccessary here: the deconstructor of ofstream can handle this for us as soon as out goes out of scope.

For more information, see the C++-reference: http://cplusplus.com/reference/fstream/ofstream/ofstream/

Now if you need to write to a file in binary form, you should do this using the actual data in the string. The easiest way to acquire this data would be using string::c_str(). So you could use:

write.write( studentPassword.c_str(), sizeof(char)*studentPassword.size() );

How do I delete a local repository in git?

In the repository directory you remove the directory named .git and that's all :). On Un*x it is hidden, so you might not see it from file browser, but

cd repository-path/
rm -r .git

should do the trick.

How to declare a local variable in Razor?

If you want a variable to be accessible across the entire page, it works well to define it at the top of the file. (You can use either an implicit or explicit type.)

@{
    // implicit type
    var something1 = "something";

    // explicit type
    string something2 = "something";
}

<div>@something1</div> @*display first variable*@
<div>@something2</div> @*display second variable*@

Rails ActiveRecord date between

Just a note that the currently accepted answer is deprecated in Rails 3. You should do this instead:

Comment.where(:created_at => @selected_date.beginning_of_day..@selected_date.end_of_day)

Or, if you want to or have to use pure string conditions, you can do:

Comment.where('created_at BETWEEN ? AND ?', @selected_date.beginning_of_day, @selected_date.end_of_day)

How do I connect to mongodb with node.js (and authenticate)?

if you continue to have problems with the native driver, you can also check out sleepy mongoose. It's a python REST server that you can simply access with node request to get to your Mongo instance. http://www.snailinaturtleneck.com/blog/2010/02/22/sleepy-mongoose-a-mongodb-rest-interface/

Open a facebook link by native Facebook app on iOS

To add yonix’s comment as an answer, the old fb://page/… URL no longer works. Apparently it was replaced by fb://profile/…, even though a page is not a profile.

Converts scss to css

This is an online/offline solution and very easy to convert. SCSS to CSS converter

enter image description here

apache redirect from non www to www

To 301 redirect all requests made directly to the domain to www you can use:

RewriteEngine On

RewriteCond %{HTTP_HOST} !^([^.]+\.[^.]+){2,}$ [NC]
RewriteRule ^(.*)$ http://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]

The benefit of this is that this will work if you have any valid subdomains, e.g.

example.com REDIRECTED TO www.example.com

foo.example.com NO REDIRECT

bar.example.com NO REDIRECT

How to change line color in EditText

If you want a flat line, you can do this easily with xml. Here is the xml example:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:top="-1dp"
        android:left="-1dp"
        android:right="-1dp"
        android:bottom="1dp"
        >
        <shape android:shape="rectangle">
            <stroke android:width="1dp" android:color="#6A9A3A"/>
        </shape>
    </item>
</layer-list>

Replace the shape with a selector if you want to provide different width and color for focused edittext.

convert double to int

My ways are :

 - Convert.ToInt32(double_value)
 - (int)double_value
 - Int32.Parse(double_value.ToString());

How to add a JAR in NetBeans

You want to add libraries to your project and in doing so you have two options as you yourself identified:

Compile-time libraries are libraries which is needed to compile your application. They are not included when your application is assembled (e.g., into a war-file). Libraries of this kind must be provided by the container running your project.

This is useful in situation when you want to vary API and implementation, or when the library is supplied by the container (which is typically the case with javax.servlet which is required to compile but provided by the application server, e.g., Apache Tomcat).

Run-time libraries are libraries which is needed both for compilation and when running your project. This is probably what you want in most cases. If for instance your project is packaged into a war/ear, then these libraries will be included in the package.

As for the other alernatives you have either global libraries using Library Manageror jdk libraries. The latter is simply your regular java libraries, while the former is just a way for your to store a set of libraries under a common name. For all your future projects, instead of manually assigning the libraries you can simply select to import them from your Library Manager.

Postgresql -bash: psql: command not found

It can be due to psql not being in PATH

$ locate psql
/usr/lib/postgresql/9.6/bin/psql

Then create a link in /usr/bin

ln -s /usr/lib/postgresql/9.6/bin/psql /usr/bin/psql

Then try to execute psql it should work.

How do I turn a python datetime into a string, with readable format date?

very old question, i know. but with the new f-strings (starting from python 3.6) there are fresh options. so here for completeness:

from datetime import datetime

dt = datetime.now()

# str.format
strg = '{:%B %d, %Y}'.format(dt)
print(strg)  # July 22, 2017

# datetime.strftime
strg = dt.strftime('%B %d, %Y')
print(strg)  # July 22, 2017

# f-strings in python >= 3.6
strg = f'{dt:%B %d, %Y}'
print(strg)  # July 22, 2017

strftime() and strptime() Behavior explains what the format specifiers mean.

var functionName = function() {} vs function functionName() {}

The first example is a function declaration:

function abc(){}

The second example is a function expression:

var abc = function() {};

The main difference is how they are hoisted (lifted and declared). In the first example, the whole function declaration is hoisted. In the second example only the var 'abc' is hoisted, its value (the function) will be undefined, and the function itself remains at the position that it is declared.

To put it simply:

//this will work
abc(param);
function abc(){}

//this would fail
abc(param);
var abc = function() {}

To study more about this topic I strongly recommend you this link

How can I convert a char to int in Java?

You can use static methods from Character class to get Numeric value from char.

char x = '9';

if (Character.isDigit(x)) { // Determines if the specified character is a digit.
    int y = Character.getNumericValue(x); //Returns the int value that the 
                                          //specified Unicode character represents.
    System.out.println(y);
}

SVN Error: Commit blocked by pre-commit hook (exit code 1) with output: Error: n/a (6)

Could it be that you have not entered a commit message? According to their twitter feed: "New functionality added. Block users from committing work without writing a log message. Find in the resources section of your control panel".

How to loop through each and every row, column and cells in a GridView and get its value

The easiest would be using a foreach:

foreach(GridViewRow row in GridView2.Rows)
{
    // here you'll get all rows with RowType=DataRow
    // others like Header are omitted in a foreach
}

Edit: According to your edits, you are accessing the column incorrectly, you should start with 0:

foreach(GridViewRow row in GridView2.Rows)
{
    for(int i = 0; i < GridView2.Columns.Count; i++)
    {
        String header = GridView2.Columns[i].HeaderText;
        String cellText = row.Cells[i].Text;
    }
}

How to check if IEnumerable is null or empty?

 public static bool AnyNotNull<TSource>(this IEnumerable<TSource> source)
    {
        return source != null && source.Any();
    }

my own extension method to check Not null and Any

How/when to use ng-click to call a route?

You can use:

<a ng-href="#/about">About</a>

If you want some dynamic variable inside href you can do like this way:

<a ng-href="{{link + 123}}">Link to 123</a>

Where link is Angular scope variable.

Why can't I define a default constructor for a struct in .NET?

public struct Rational 
{
    private long numerator;
    private long denominator;

    public Rational(long num = 0, long denom = 1)   // This is allowed!!!
    {
        numerator   = num;
        denominator = denom;
    }
}

"Stack overflow in line 0" on Internet Explorer

You can turn off the "Disable Script Debugging" option inside of Internet Explorer and start debugging with Visual Studio if you happen to have that around.

I've found that it is one of few ways to diagnose some of those IE specific issues.

Error importing Seaborn module in Python

As @avp says the bash line pip install seaborn should work I just had the same problem and and restarting the notebook didn't seem to work but running the command as jupyter line magic was a neat way to fix the problem without restarting the notebook

Jupyter Code-Cell:

%%bash
pip install seaborn