Error: the entity type requires a primary key

Your Id property needs to have a setter. However the setter can be private. The [Key] attribute is not necessary if the property is named "Id" as it will find it through the naming convention where it looks for a key with the name "Id".

public Guid Id { get; }              // Will not work
public Guid Id { get; set; }         // Will work
public Guid Id { get; private set; } // Will also work

Why is visible="false" not working for a plain html table?

For the best practice - use style="display:"

it will work every where..

z-index not working with fixed positioning

This question can be solved in a number of ways, but really, knowing the stacking rules allows you to find the best answer that works for you.

Solutions

The <html> element is your only stacking context, so just follow the stacking rules inside a stacking context and you will see that elements are stacked in this order

The stacking context’s root element (the <html> element in this case)

Positioned elements (and their children) with negative z-index values (higher values are stacked in front of lower values; elements with the same value are stacked according to appearance in the HTML)

Non-positioned elements (ordered by appearance in the HTML)

Positioned elements (and their children) with a z-index value of auto (ordered by appearance in the HTML)

Positioned elements (and their children) with positive z-index values (higher values are stacked in front of lower values; elements with the same value are stacked according to appearance in the HTML)

So you can

set a z-index of -1, for #under positioned -ve z-index appear behind non-positioned #over element
set the position of #over to relative so that rule 5 applies to it

The Real Problem

Developers should know the following before trying to change the stacking order of elements.

When a stacking context is formed
- By default, the <html> element is the root element and is the first stacking context
Stacking order within a stacking context

The Stacking order and stacking context rules below are from this link

When a stacking context is formed

When an element is the root element of a document (the <html> element)
When an element has a position value other than static and a z-index value other than auto
When an element has an opacity value less than 1
Several newer CSS properties also create stacking contexts. These include: transforms, filters, css-regions, paged media, and possibly others. https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Positioning/Understanding_z_index/The_stacking_context
As a general rule, it seems that if a CSS property requires rendering in an offscreen context, it must create a new stacking context.

Stacking Order within a Stacking Context

The order of elements:

The stacking context’s root element (the <html> element is the only stacking context by default, but any element can be a root element for a stacking context, see rules above)
- You cannot put a child element behind a root stacking context element
Positioned elements (and their children) with negative z-index values (higher values are stacked in front of lower values; elements with the same value are stacked according to appearance in the HTML)
Non-positioned elements (ordered by appearance in the HTML)
Positioned elements (and their children) with a z-index value of auto (ordered by appearance in the HTML)
Positioned elements (and their children) with positive z-index values (higher values are stacked in front of lower values; elements with the same value are stacked according to appearance in the HTML)

What's the difference between all the Selection Segues?

For those who prefer a bit more practical learning, select the segue in dock, open the attribute inspector and switch between different kinds of segues (dropdown "Kind"). This will reveal options specific for each of them: for example you can see that "present modally" allows you to choose a transition type etc.

How to send PUT, DELETE HTTP request in HttpURLConnection?

I would recommend Apache HTTPClient.

How to assert two list contain the same elements in Python?

As of Python 3.2 unittest.TestCase.assertItemsEqual(doc) has been replaced by unittest.TestCase.assertCountEqual(doc) which does exactly what you are looking for, as you can read from the python standard library documentation. The method is somewhat misleadingly named but it does exactly what you are looking for.

a and b have the same elements in the same number, regardless of their order

Here a simple example which compares two lists having the same elements but in a different order.

using assertCountEqual the test will succeed
using assertListEqual the test will fail due to the order difference of the two lists

Here a little example script.

import unittest


class TestListElements(unittest.TestCase):
    def setUp(self):
        self.expected = ['foo', 'bar', 'baz']
        self.result = ['baz', 'foo', 'bar']

    def test_count_eq(self):
        """Will succeed"""
        self.assertCountEqual(self.result, self.expected)

    def test_list_eq(self):
        """Will fail"""
        self.assertListEqual(self.result, self.expected)

if __name__ == "__main__":
    unittest.main()

Side Note : Please make sure that the elements in the lists you are comparing are sortable.

Use jquery click to handle anchor onClick()

Lets take an anchor tag with an onclick event, that calls a Javascript function.

<a href="#" onClick="showDiv(1);">1</a>

Now in javascript write the below code

function showDiv(pageid)
{
   alert(pageid);
}

This will show you an alert of "1"....

Regex matching beginning AND end strings

Well, the simple regex is this:

/^dbo\..*_fn$/

It would be better, however, to use the string manipulation functionality of whatever programming language you're using to slice off the first four and the last three characters of the string and check whether they're what you want.

Mongoose.js: Find user by username LIKE value

router.route('/product/name/:name')
.get(function(req, res) {

    var regex = new RegExp(req.params.name, "i")
    ,   query = { description: regex };

    Product.find(query, function(err, products) {
        if (err) {
            res.json(err);
        }

        res.json(products);
    });

});

Ignoring upper case and lower case in Java

You have to use the String method .toLowerCase() or .toUpperCase() on both the input and the string you are trying to match it with.

Example:

public static void findPatient() {
    System.out.print("Enter part of the patient name: ");
    String name = sc.nextLine();

    System.out.print(myPatientList.showPatients(name));
}

//the other class
ArrayList<String> patientList;

public void showPatients(String name) {
    boolean match = false;

    for(String matchingname : patientList) {
        if (matchingname.toLowerCase().contains(name.toLowerCase())) {
            match = true;
        }
    }
}

WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for 'jquery'. Please add a ScriptResourceMapping named jquery(case-sensitive)

to add a little more to the answer from b_levitt... on global.asax:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using System.Web.UI;

namespace LoginPage
{
    public class Global : System.Web.HttpApplication
    {
        protected void Application_Start(object sender, EventArgs e)
        {
            string JQueryVer = "1.11.3";
            ScriptManager.ScriptResourceMapping.AddDefinition("jquery", new ScriptResourceDefinition
            {
                Path = "~/js/jquery-" + JQueryVer + ".min.js",
                DebugPath = "~/js/jquery-" + JQueryVer + ".js",
                CdnPath = "http://ajax.aspnetcdn.com/ajax/jQuery/jquery-" + JQueryVer + ".min.js",
                CdnDebugPath = "http://ajax.aspnetcdn.com/ajax/jQuery/jquery-" + JQueryVer + ".js",
                CdnSupportsSecureConnection = true,
                LoadSuccessExpression = "window.jQuery"
            });
        }
    }
}

on your default.aspx

<body>
   <form id="UserSectionForm" runat="server">
     <asp:ScriptManager ID="ScriptManager" runat="server">
          <Scripts>
               <asp:ScriptReference Name="jquery" />
          </Scripts>
     </asp:ScriptManager>
     <%--rest of your markup goes here--%>         
   </form>
</body>

Base64 encoding and decoding in client-side Javascript

In Gecko/WebKit-based browsers (Firefox, Chrome and Safari) and Opera, you can use btoa() and atob().

Original answer: How can you encode a string to Base64 in JavaScript?

SQL Server - SELECT FROM stored procedure

You need to declare a table type which contains the same number of columns your store procedure is returning. Data types of the columns in the table type and the columns returned by the procedures should be same

declare @MyTableType as table
(
FIRSTCOLUMN int
,.....
)

Then you need to insert the result of your stored procedure in your table type you just defined

Insert into @MyTableType 
EXEC [dbo].[MyStoredProcedure]

In the end just select from your table type

Select * from @MyTableType

Returning value from called function in a shell script

I think returning 0 for succ/1 for fail (glenn jackman) and olibre's clear and explanatory answer says it all; just to mention a kind of "combo" approach for cases where results are not binary and you'd prefer to set a variable rather than "echoing out" a result (for instance if your function is ALSO suppose to echo something, this approach will not work). What then? (below is Bourne Shell)

# Syntax _w (wrapReturn)
# arg1 : method to wrap
# arg2 : variable to set
_w(){
eval $1
read $2 <<EOF
$?
EOF
eval $2=\$$2
}

as in (yep, the example is somewhat silly, it's just an.. example)

getDay(){
  d=`date '+%d'`
  [ $d -gt 255 ] && echo "Oh no a return value is 0-255!" && BAIL=0 # this will of course never happen, it's just to clarify the nature of returns
  return $d
}

dayzToSalary(){
  daysLeft=0
  if [ $1 -lt 26 ]; then 
      daysLeft=`expr 25 - $1`
  else
     lastDayInMonth=`date -d "`date +%Y%m01` +1 month -1 day" +%d`
     rest=`expr $lastDayInMonth - 25`
     daysLeft=`expr 25 + $rest`
  fi
  echo "Mate, it's another $daysLeft days.."
}

# main
_w getDay DAY # call getDay, save the result in the DAY variable
dayzToSalary $DAY

multiple where condition codeigniter

you can use an array and pass the array.

Associative array method:
$array = array('name' => $name, 'title' => $title, 'status' => $status);

$this->db->where($array); 

// Produces: WHERE name = 'Joe' AND title = 'boss' AND status = 'active'

Or if you want to do something other than = comparison

$array = array('name !=' => $name, 'id <' => $id, 'date >' => $date);

$this->db->where($array);

Move a view up only when the keyboard covers an input field

The one I found to work perfectly for me was this:

func textFieldDidBeginEditing(textField: UITextField) {
    if textField == email || textField == password {
        animateViewMoving(true, moveValue: 100)
    }
}

func textFieldDidEndEditing(textField: UITextField) {
    if textField == email || textField == password {
        animateViewMoving(false, moveValue: 100)
    }
}

func animateViewMoving (up:Bool, moveValue :CGFloat){
    let movementDuration:NSTimeInterval = 0.3
    let movement:CGFloat = ( up ? -moveValue : moveValue)

    UIView.beginAnimations("animateView", context: nil)
    UIView.setAnimationBeginsFromCurrentState(true)
    UIView.setAnimationDuration(movementDuration)

    self.view.frame = CGRectOffset(self.view.frame, 0, movement)
    UIView.commitAnimations()
}

You can also change the height values. Remove the "if statement" if you want to use it for all text fields.

You can even use this for all controls that require user input like TextView.

What are the alternatives now that the Google web search API has been deprecated?

Faroo has a free Web Search API

A Windows equivalent of the Unix tail command

If you use PowerShell then this works:

Get-Content filenamehere -Wait -Tail 30

Posting Stefan's comment from below, so people don't miss it

PowerShell 3 introduces a -Tail parameter to include only the last x lines

Is it not possible to stringify an Error using JSON.stringify?

JSON.stringify(err, Object.getOwnPropertyNames(err))

seems to work

[from a comment by /u/ub3rgeek on /r/javascript] and felixfbecker's comment below

Rails: call another controller action from a controller

Composition to the rescue!

Given the reason, rather than invoking actions across controllers one should design controllers to seperate shared and custom parts of the code. This will help to avoid both - code duplication and breaking MVC pattern.

Although that can be done in a number of ways, using concerns (composition) is a good practice.

# controllers/a_controller.rb
class AController < ApplicationController
  include Createable

  private def redirect_url
    'one/url'
  end
end

# controllers/b_controller.rb
class BController < ApplicationController
  include Createable

  private def redirect_url
    'another/url'
  end
end

# controllers/concerns/createable.rb
module Createable
  def create
    do_usefull_things
    redirect_to redirect_url
  end
end

Hope that helps.

Python/Django: log to console under runserver, log to file under Apache

You can do this pretty easily with tagalog (https://github.com/dorkitude/tagalog)

For instance, while the standard python module writes to a file object opened in append mode, the App Engine module (https://github.com/dorkitude/tagalog/blob/master/tagalog_appengine.py) overrides this behavior and instead uses logging.INFO.

To get this behavior in an App Engine project, one could simply do:

import tagalog.tagalog_appengine as tagalog
tagalog.log('whatever message', ['whatever','tags'])

You could extend the module yourself and overwrite the log function without much difficulty.

How can I read command line parameters from an R script?

Dirk's answer here is everything you need. Here's a minimal reproducible example.

I made two files: exmpl.bat and exmpl.R.

exmpl.bat:

set R_Script="C:\Program Files\R-3.0.2\bin\RScript.exe"
%R_Script% exmpl.R 2010-01-28 example 100 > exmpl.batch 2>&1

Alternatively, using Rterm.exe:

set R_TERM="C:\Program Files\R-3.0.2\bin\i386\Rterm.exe"
%R_TERM% --no-restore --no-save --args 2010-01-28 example 100 < exmpl.R > exmpl.batch 2>&1

exmpl.R:

options(echo=TRUE) # if you want see commands in output file
args <- commandArgs(trailingOnly = TRUE)
print(args)
# trailingOnly=TRUE means that only your arguments are returned, check:
# print(commandArgs(trailingOnly=FALSE))

start_date <- as.Date(args[1])
name <- args[2]
n <- as.integer(args[3])
rm(args)

# Some computations:
x <- rnorm(n)
png(paste(name,".png",sep=""))
plot(start_date+(1L:n), x)
dev.off()

summary(x)

Save both files in the same directory and start exmpl.bat. In the result you'll get:

example.png with some plot
exmpl.batch with all that was done

You could also add an environment variable %R_Script%:

"C:\Program Files\R-3.0.2\bin\RScript.exe"

and use it in your batch scripts as %R_Script% <filename.r> <arguments>

Differences between RScript and Rterm:

Rscript has simpler syntax
Rscript automatically chooses architecture on x64 (see R Installation and Administration, 2.6 Sub-architectures for details)
Rscript needs options(echo=TRUE) in the .R file if you want to write the commands to the output file

Mask for an Input to allow phone numbers?

It can be done using a directive. Below is the plunker of the input mask I built.

https://plnkr.co/edit/hRsmd0EKci6rjGmnYFRr?p=preview

Code:

import {Directive, Attribute, ElementRef, OnInit, OnChanges, Input, SimpleChange } from 'angular2/core';
import {NgControl, DefaultValueAccessor} from 'angular2/common';

@Directive({
selector: '[mask-input]',
host: {
    //'(keyup)': 'onInputChange()',
    '(click)': 'setInitialCaretPosition()'
}, 
inputs: ['modify'],
providers: [DefaultValueAccessor]
})
export class MaskDirective implements OnChanges {
maskPattern: string;
placeHolderCounts: any;
dividers: string[];
modelValue: string;
viewValue: string;
intialCaretPos: any;
numOfChar: any;
@Input() modify: any; 

constructor(public model: NgControl, public ele: ElementRef, @Attribute("mask-input") maskPattern: string) {
    this.dividers = maskPattern.replace(/\*/g, "").split("");
    this.dividers.push("_");
    this.generatePattern(maskPattern);   
    this.numOfChar = 0;
}

ngOnChanges(changes: { [propertyName: string]: SimpleChange }) {
    this.onInputChange(changes);
}

onInputChange(changes: { [propertyName: string]: SimpleChange }) {             
    this.modelValue = this.getModelValue();
    var caretPosition = this.ele.nativeElement.selectionStart;
    if (this.viewValue != null) {
      this.numOfChar = this.getNumberOfChar(caretPosition);
    }
    var stringToFormat = this.modelValue;        

    if (stringToFormat.length < 10) {
        stringToFormat = this.padString(stringToFormat);
    }

    this.viewValue = this.format(stringToFormat);

    if (this.viewValue != null) {
        caretPosition = this.setCaretPosition(this.numOfChar);
    }

    this.model.viewToModelUpdate(this.modelValue);
    this.model.valueAccessor.writeValue(this.viewValue);
    this.ele.nativeElement.selectionStart = caretPosition;
    this.ele.nativeElement.selectionEnd = caretPosition;
}

generatePattern(patternString) {
    this.placeHolderCounts = (patternString.match(/\*/g) || []).length;
    for (var i = 0; i < this.placeHolderCounts; i++) {
        patternString = patternString.replace('*', "{" + i + "}");
    }
    this.maskPattern = patternString;
}

format(s) {
    var formattedString = this.maskPattern;
    for (var i = 0; i < this.placeHolderCounts; i++) {
        formattedString = formattedString.replace("{" + i + "}", s.charAt(i));
    }
    return formattedString;
}

padString(s) {
    var pad = "__________";
    return (s + pad).substring(0, pad.length);
}

getModelValue() {
    var modelValue = this.model.value;
    if (modelValue == null) {
        return "";
    }
    for (var i = 0; i < this.dividers.length; i++) {
        while (modelValue.indexOf(this.dividers[i]) > -1) {
            modelValue = modelValue.replace(this.dividers[i], "");
        }
    }
    return modelValue;
}

setInitialCaretPosition() {
    var caretPosition = this.setCaretPosition(this.modelValue.length);

    this.ele.nativeElement.selectionStart = caretPosition;
    this.ele.nativeElement.selectionEnd = caretPosition;

}

setCaretPosition(num) {
    var notDivider = true;
    var caretPos = 1;
    for (; num > 0; caretPos++) {
      var ch = this.viewValue.charAt(caretPos);
      if (!this.isDivider(ch)) {
        num--;
      }
    }
    return caretPos;
}

isDivider(ch) {
    for (var i = 0; i < this.dividers.length; i++) {
          if (ch == this.dividers[i]) {
              return true;
          }
    }
}

getNumberOfChar(pos) {
  var num = 0;
  var containDividers = false;
  for (var i = 0; i < pos; i++) {
    var ch = this.modify.charAt(i);

    if (!this.isDivider(ch)) {
      num++;
    }
    else {
      containDividers = true;
    }
  }
  if (containDividers) {
    return num;
  }
  else {
    return this.numOfChar;
  }
}

}

Note: there are still a few bugs.

Razor/CSHTML - Any Benefit over what we have?

Everything is encoded by default!!! This is pretty huge.
Declarative helpers can be compiled so you don't need to do anything special to share them. I think they will replace .ascx controls to some extent. You have to jump through some hoops to use an .ascx control in another project.
You can make a section required which is nice.

How to save select query results within temporary table?

In Sqlite:

CREATE TABLE T AS
SELECT * FROM ...;
-- Use temporary table `T`
DROP TABLE T;

Replacing Numpy elements if condition is met

You can create your mask array in one step like this

mask_data = input_mask_data < 3

This creates a boolean array which can then be used as a pixel mask. Note that we haven't changed the input array (as in your code) but have created a new array to hold the mask data - I would recommend doing it this way.

>>> input_mask_data = np.random.randint(0, 5, (3, 4))
>>> input_mask_data
array([[1, 3, 4, 0],
       [4, 1, 2, 2],
       [1, 2, 3, 0]])
>>> mask_data = input_mask_data < 3
>>> mask_data
array([[ True, False, False,  True],
       [False,  True,  True,  True],
       [ True,  True, False,  True]], dtype=bool)
>>>

Can I set max_retries for requests.request?

A cleaner way to gain higher control might be to package the retry stuff into a function and make that function retriable using a decorator and whitelist the exceptions.

I have created the same here: http://www.praddy.in/retry-decorator-whitelisted-exceptions/

Reproducing the code in that link :

def retry(exceptions, delay=0, times=2):
"""
A decorator for retrying a function call with a specified delay in case of a set of exceptions

Parameter List
-------------
:param exceptions:  A tuple of all exceptions that need to be caught for retry
                                    e.g. retry(exception_list = (Timeout, Readtimeout))
:param delay: Amount of delay (seconds) needed between successive retries.
:param times: no of times the function should be retried


"""
def outer_wrapper(function):
    @functools.wraps(function)
    def inner_wrapper(*args, **kwargs):
        final_excep = None  
        for counter in xrange(times):
            if counter > 0:
                time.sleep(delay)
            final_excep = None
            try:
                value = function(*args, **kwargs)
                return value
            except (exceptions) as e:
                final_excep = e
                pass #or log it

        if final_excep is not None:
            raise final_excep
    return inner_wrapper

return outer_wrapper

@retry(exceptions=(TimeoutError, ConnectTimeoutError), delay=0, times=3)
def call_api():

How can I display a messagebox in ASP.NET?

create a simple JavaScript function having one line of code-"alert("Hello this is an Alert")" and instead on OnClick() ,use OnClientClick() method.

`<html xmlns="http://www.w3.org/1999/xhtml">
 <head runat="server">
 <title></title>
 <script type="text/javascript" language="javascript">
    function showAlert() {
        alert("Hello this is an Alert")
    }
 </script>
 </head>
 <body>
 <form id="form1" runat="server">
 <div>
 <asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="showAlert()" />
 </div>
 </form>
 </body>
 </html>`

Convert HTML to NSAttributedString in iOS

Using of NSHTMLTextDocumentType is slow and it is hard to control styles. I suggest you to try my library which is called Atributika. It has its own very fast HTML parser. Also you can have any tag names and define any style for them.

Example:

let str = "<strong>Hello</strong> World!".style(tags:
    Style("strong").font(.boldSystemFont(ofSize: 15))).attributedString

label.attributedText = str

You can find it here https://github.com/psharanda/Atributika

How to write file in UTF-8 format?

<?php
function writeUTF8File($filename,$content) { 
        $f=fopen($filename,"w"); 
        # Now UTF-8 - Add byte order mark 
        fwrite($f, pack("CCC",0xef,0xbb,0xbf)); 
        fwrite($f,$content); 
        fclose($f); 
} 
?>

What does "hard coded" mean?

"Hard Coding" means something that you want to embeded with your program or any project that can not be changed directly. For example if you are using a database server, then you must hardcode to connect your database with your project and that can not be changed by user. Because you have hard coded.

How to lock orientation of one view controller to portrait mode only in Swift

I experimented a little bit and I managed to find clean solution for this problem. The approach is based on the view tagging via view->tag

In the target ViewController just assign the tag to the root view like in the following code example:

class MyViewController: BaseViewController {

  // declare unique view tag identifier
  static let ViewTag = 2105981;

  override func viewDidLoad()
  {
    super.viewDidLoad();
    // assign the value to the current root view
    self.view.tag = MyViewController.ViewTag;
  }

And finally in the AppDelegate.swift check if the currently shown view is the one we tagged:

func application(_ application: UIApplication, supportedInterfaceOrientationsFor window: UIWindow?) -> UIInterfaceOrientationMask
{
    if (window?.viewWithTag(DesignerController.ViewTag)) != nil {
        return .portrait;
    }
    return .all;
}

This approach has been tested with my simulator and seems it works fine.

Note: the marked view will be also found if current MVC is overlapped with some child ViewController in navigation stack.

Specifying maxlength for multiline textbox

Here's how we did it (keeps all code in one place):

<asp:TextBox ID="TextBox1" runat="server" TextMode="MultiLine"/>
<% TextBox1.Attributes["maxlength"] = "1000"; %>

Just in case someone still using webforms in 2018..

AJAX reload page with POST

If you want to refresh the entire page, it makes no sense to use AJAX. Use normal Javascript to post the form element in that page. Make sure the form submits to the same page, or that the form submits to a page which then redirects back to that page

Javascript to be used (always in myForm.php):

function submitform()
{
  document.getElementById('myForm').submit();
}

Suppose your form is on myForm.php: Method 1:

<form action="./myForm.php" method="post" id="myForm">
    ...
</form>

Method 2:

myForm.php:

<form action="./myFormActor.php" method="post" id="myForm">
    ...
</form>

myFormActor.php:

<?php
    //all code here, no output
    header("Location: ./myForm.php");
?>

jquery: get id from class selector

Doh.. If I get you right, it should be as simple as:

_x000D_

$('.test').click(function() {_x000D_
  console.log(this.id);_x000D_
});

_x000D_

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<a href="#" class="test" id="test_1">Some text</a>_x000D_
<a href="#" class="test" id="test_2">Some text</a>_x000D_
<a href="#" class="test" id="test_3">Some text</a>

_x000D_

You can just access the id property over the underlaying dom node, within the event handler.

MongoDB Data directory /data/db not found

MongoDB needs data directory to store data. Default path is /data/db

When you start MongoDB engine, it searches this directory which is missing in your case. Solution is create this directory and assign rwx permission to user.

If you want to change the path of your data directory then you should specify it while starting mongod server like,

mongod --dbpath /data/<path> --port <port no>

This should help you start your mongod server with custom path and port.

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

That worked for me was to review all the certificates on KeyChain to be as Use systems Default, all the certificates must to be with this configuration. Was the only thing that worked, and also be shure that no certificates are repeated.

how to use ng-option to set default value of select element

Just to add up, I did something like this.

 <select class="form-control" data-ng-model="itemSelect" ng-change="selectedTemplate(itemSelect)" autofocus>
        <option value="undefined" [selected]="itemSelect.Name == undefined" disabled="disabled">Select template...</option>
        <option ng-repeat="itemSelect in templateLists" value="{{itemSelect.ID}}">{{itemSelect.Name}}</option></select>

Disable back button in android

You just need to override the method for back button. You can leave the method empty if you want so that nothing will happen when you press back button. Please have a look at the code below:

@Override
public void onBackPressed() 
{
   // Your Code Here. Leave empty if you want nothing to happen on back press.
}

What is "overhead"?

You could use a dictionary. The definition is the same. But to save you time, Overhead is work required to do the productive work. For instance, an algorithm runs and does useful work, but requires memory to do its work. This memory allocation takes time, and is not directly related to the work being done, therefore is overhead.

Convert array of strings to List<string>

Just use this constructor of List<T>. It accepts any IEnumerable<T> as an argument.

string[] arr = ...
List<string> list = new List<string>(arr);

How to merge a specific commit in Git

Let's say you want to merge commit e27af03 from branch X to master.

git checkout master
git cherry-pick e27af03
git push

Which port(s) does XMPP use?

The ports required will be different for your XMPP Server and any XMPP Clients. Most "modern" XMPP Servers follow the defined IANA Ports for Server-to-Server 5269 and for Client-to-Server 5222. Any additional ports depends on what features you enable on the Server, i.e. if you offer BOSH then you may need to open port 80.

File Transfer is highly dependent on both the Clients you use and the Server as to what port it will use, but most of them also negotiate the connect via your existing XMPP Client-to-Server link so the required port opening will be client side (or proxied via port 80.)

How do you grep a file and get the next 5 lines

You want:

grep -A 5 '19:55' file

From man grep:

Context Line Control

-A NUM, --after-context=NUM

Print NUM lines of trailing context after matching lines.  
Places a line containing a gup separator (described under --group-separator) 
between contiguous groups of matches.  With the -o or --only-matching
option, this has no effect and a warning is given.

-B NUM, --before-context=NUM

Print NUM lines of leading context before matching lines.  
Places a line containing a group separator (described under --group-separator) 
between contiguous groups of matches.  With the -o or --only-matching
option, this has no effect and a warning is given.

-C NUM, -NUM, --context=NUM

Print NUM lines of output context.  Places a line containing a group separator
(described under --group-separator) between contiguous groups of matches.  
With the -o or --only-matching option,  this  has  no effect and a warning
is given.

--group-separator=SEP

Use SEP as a group separator. By default SEP is double hyphen (--).

--no-group-separator

Use empty string as a group separator.

SQL Server Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >=

Check to see if there are any triggers on the table you are trying to execute queries against. They can sometimes throw this error as they are trying to run the update/select/insert trigger that is on the table.

You can modify your query to disable then enable the trigger if the trigger DOES NOT need to be executed for whatever query you are trying to run.

ALTER TABLE your_table DISABLE TRIGGER [the_trigger_name]

UPDATE    your_table
SET     Gender = 'Female'
WHERE     (Gender = 'Male')

ALTER TABLE your_table ENABLE TRIGGER [the_trigger_name]

Declaring an HTMLElement Typescript

Note that const declarations are block-scoped.

const el: HTMLElement | null = document.getElementById('content');

if (el) {
  const definitelyAnElement: HTMLElement = el;
}

So the value of definitelyAnElement is not accessible outside of the {}.

(I would have commented above, but I do not have enough Reputation apparently.)

Keyword not supported: "data source" initializing Entity Framework Context

Make sure you have Data Source and not DataSource in your connection string. The space is important. Trust me. I'm an idiot.

Uncaught TypeError: Cannot use 'in' operator to search for 'length' in

The in operator only works on objects. You are using it on a string. Make sure your value is an object before you using $.each. In this specific case, you have to parse the JSON:

$.each(JSON.parse(myData), ...);

String replacement in java, similar to a velocity template

Take a look at the java.text.MessageFormat class, MessageFormat takes a set of objects, formats them, then inserts the formatted strings into the pattern at the appropriate places.

Object[] params = new Object[]{"hello", "!"};
String msg = MessageFormat.format("{0} world {1}", params);

scrollIntoView Scrolls just too far

Fix it in 20 seconds:

This solution belongs to @Arseniy-II, I have just simplified it into a function.

function _scrollTo(selector, yOffset = 0){
  const el = document.querySelector(selector);
  const y = el.getBoundingClientRect().top + window.pageYOffset + yOffset;

  window.scrollTo({top: y, behavior: 'smooth'});
}

Usage (you can open up the console right here in StackOverflow and test it out):

_scrollTo('#question-header', 0);

I'm currently using this in production and it is working just fine.

How to bind inverse boolean properties in WPF?

Have you considered an IsNotReadOnly property? If the object being bound is a ViewModel in a MVVM domain, then the additional property makes perfect sense. If it's a direct Entity model, you might consider composition and presenting a specialized ViewModel of your entity to the form.

com.google.android.gms:play-services-measurement-base is being requested by various other libraries

replace the "+" with version number, it would choose the latest version. like this:

implementation 'com.google.firebase:firebase-analytics:+'

Change Primary Key

Sometimes when we do these steps:

 alter table my_table drop constraint my_pk; 
 alter table my_table add constraint my_pk primary key (city_id, buildtime, time);

The last statement fails with

ORA-00955 "name is already used by an existing object"

Oracle usually creates an unique index with the same name my_pk. In such a case you can drop the unique index or rename it based on whether the constraint is still relevant.

You can combine the dropping of primary key constraint and unique index into a single sql statement:

alter table my_table drop constraint my_pk drop index;

check this: ORA-00955 "name is already used by an existing object"

Which characters are valid/invalid in a JSON key name?

No. Any valid string is a valid key. It can even have " as long as you escape it:

{"The \"meaning\" of life":42}

There is perhaps a chance you'll encounter difficulties loading such values into some languages, which try to associate keys with object field names. I don't know of any such cases, however.

Can functions be passed as parameters?

This is the simplest way I can come with.

package main

import "fmt"

func main() {
    g := greeting
    getFunc(g)
}

func getFunc(f func()) {
    f()
}

func greeting() {
    fmt.Println("Hello")
}

How to write a confusion matrix in Python?

Scikit-Learn provides a confusion_matrix function

from sklearn.metrics import confusion_matrix
y_actu = [2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2]
y_pred = [0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2]
confusion_matrix(y_actu, y_pred)

which output a Numpy array

array([[3, 0, 0],
       [0, 1, 2],
       [2, 1, 3]])

But you can also create a confusion matrix using Pandas:

import pandas as pd
y_actu = pd.Series([2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2], name='Actual')
y_pred = pd.Series([0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2], name='Predicted')
df_confusion = pd.crosstab(y_actu, y_pred)

You will get a (nicely labeled) Pandas DataFrame:

Predicted  0  1  2
Actual
0          3  0  0
1          0  1  2
2          2  1  3

If you add margins=True like

df_confusion = pd.crosstab(y_actu, y_pred, rownames=['Actual'], colnames=['Predicted'], margins=True)

you will get also sum for each row and column:

Predicted  0  1  2  All
Actual
0          3  0  0    3
1          0  1  2    3
2          2  1  3    6
All        5  2  5   12

You can also get a normalized confusion matrix using:

df_conf_norm = df_confusion / df_confusion.sum(axis=1)

Predicted         0         1         2
Actual
0          1.000000  0.000000  0.000000
1          0.000000  0.333333  0.333333
2          0.666667  0.333333  0.500000

You can plot this confusion_matrix using

import matplotlib.pyplot as plt
def plot_confusion_matrix(df_confusion, title='Confusion matrix', cmap=plt.cm.gray_r):
    plt.matshow(df_confusion, cmap=cmap) # imshow
    #plt.title(title)
    plt.colorbar()
    tick_marks = np.arange(len(df_confusion.columns))
    plt.xticks(tick_marks, df_confusion.columns, rotation=45)
    plt.yticks(tick_marks, df_confusion.index)
    #plt.tight_layout()
    plt.ylabel(df_confusion.index.name)
    plt.xlabel(df_confusion.columns.name)

plot_confusion_matrix(df_confusion)

plot confusion matrix

Or plot normalized confusion matrix using:

plot_confusion_matrix(df_conf_norm)

plot confusion matrix normalized

You might also be interested by this project https://github.com/pandas-ml/pandas-ml and its Pip package https://pypi.python.org/pypi/pandas_ml

With this package confusion matrix can be pretty-printed, plot. You can binarize a confusion matrix, get class statistics such as TP, TN, FP, FN, ACC, TPR, FPR, FNR, TNR (SPC), LR+, LR-, DOR, PPV, FDR, FOR, NPV and some overall statistics

In [1]: from pandas_ml import ConfusionMatrix
In [2]: y_actu = [2, 0, 2, 2, 0, 1, 1, 2, 2, 0, 1, 2]
In [3]: y_pred = [0, 0, 2, 1, 0, 2, 1, 0, 2, 0, 2, 2]
In [4]: cm = ConfusionMatrix(y_actu, y_pred)
In [5]: cm.print_stats()
Confusion Matrix:

Predicted  0  1  2  __all__
Actual
0          3  0  0        3
1          0  1  2        3
2          2  1  3        6
__all__    5  2  5       12


Overall Statistics:

Accuracy: 0.583333333333
95% CI: (0.27666968568210581, 0.84834777019156982)
No Information Rate: ToDo
P-Value [Acc > NIR]: 0.189264302376
Kappa: 0.354838709677
Mcnemar's Test P-Value: ToDo


Class Statistics:

Classes                                        0          1          2
Population                                    12         12         12
P: Condition positive                          3          3          6
N: Condition negative                          9          9          6
Test outcome positive                          5          2          5
Test outcome negative                          7         10          7
TP: True Positive                              3          1          3
TN: True Negative                              7          8          4
FP: False Positive                             2          1          2
FN: False Negative                             0          2          3
TPR: (Sensitivity, hit rate, recall)           1  0.3333333        0.5
TNR=SPC: (Specificity)                 0.7777778  0.8888889  0.6666667
PPV: Pos Pred Value (Precision)              0.6        0.5        0.6
NPV: Neg Pred Value                            1        0.8  0.5714286
FPR: False-out                         0.2222222  0.1111111  0.3333333
FDR: False Discovery Rate                    0.4        0.5        0.4
FNR: Miss Rate                                 0  0.6666667        0.5
ACC: Accuracy                          0.8333333       0.75  0.5833333
F1 score                                    0.75        0.4  0.5454545
MCC: Matthews correlation coefficient  0.6831301  0.2581989  0.1690309
Informedness                           0.7777778  0.2222222  0.1666667
Markedness                                   0.6        0.3  0.1714286
Prevalence                                  0.25       0.25        0.5
LR+: Positive likelihood ratio               4.5          3        1.5
LR-: Negative likelihood ratio                 0       0.75       0.75
DOR: Diagnostic odds ratio                   inf          4          2
FOR: False omission rate                       0        0.2  0.4285714

I noticed that a new Python library about Confusion Matrix named PyCM is out: maybe you can have a look.

Nginx location priority

From the HTTP core module docs:

Directives with the "=" prefix that match the query exactly. If found, searching stops.
All remaining directives with conventional strings. If this match used the "^~" prefix, searching stops.
Regular expressions, in the order they are defined in the configuration file.
If #3 yielded a match, that result is used. Otherwise, the match from #2 is used.

Example from the documentation:

location  = / {
  # matches the query / only.
  [ configuration A ] 
}
location  / {
  # matches any query, since all queries begin with /, but regular
  # expressions and any longer conventional blocks will be
  # matched first.
  [ configuration B ] 
}
location /documents/ {
  # matches any query beginning with /documents/ and continues searching,
  # so regular expressions will be checked. This will be matched only if
  # regular expressions don't find a match.
  [ configuration C ] 
}
location ^~ /images/ {
  # matches any query beginning with /images/ and halts searching,
  # so regular expressions will not be checked.
  [ configuration D ] 
}
location ~* \.(gif|jpg|jpeg)$ {
  # matches any request ending in gif, jpg, or jpeg. However, all
  # requests to the /images/ directory will be handled by
  # Configuration D.   
  [ configuration E ] 
}

If it's still confusing, here's a longer explanation.

Python 3 sort a dict by its values

from collections import OrderedDict
from operator import itemgetter    

d = {"aa": 3, "bb": 4, "cc": 2, "dd": 1}
print(OrderedDict(sorted(d.items(), key = itemgetter(1), reverse = True)))

prints

OrderedDict([('bb', 4), ('aa', 3), ('cc', 2), ('dd', 1)])

Though from your last sentence, it appears that a list of tuples would work just fine, e.g.

from operator import itemgetter  

d = {"aa": 3, "bb": 4, "cc": 2, "dd": 1}
for key, value in sorted(d.items(), key = itemgetter(1), reverse = True):
    print(key, value)

which prints

bb 4
aa 3
cc 2
dd 1

How to send data to COM PORT using JAVA?

This question has been asked and answered many times:

Read file from serial port using Java

Reading serial port in Java

Reading file from serial port in Java

Is there Java library or framework for accessing Serial ports?

Java Serial Communication on Windows

to reference a few.

Personally I recommend SerialPort from http://serialio.com - ~~it's not free, but it's well worth the developer (no royalties) licensing fee for any commercial project~~. Sadly, it is no longer royalty free to deploy, and SerialIO.com seems to have remade themselves as a hardware seller; I had to search for information on SerialPort.

From personal experience, I strongly recommend against the Sun, IBM and RxTx implementations, all of which were unstable in 24/7 use. Refer to my answers on some of the aforementioned questions for details. To be perfectly fair, RxTx may have come a long way since I tried it, though the Sun and IBM implementations were essentially abandoned, even back then.

A newer free option that looks promising and may be worth trying is jSSC (Java Simple Serial Connector), as suggested by @Jodes comment.

open read and close a file in 1 line of code

I frequently do something like this when I need to get a few lines surrounding something I've grepped in a log file:

$ grep -n "xlrd" requirements.txt | awk -F ":" '{print $1}'
54

$ python -c "with open('requirements.txt') as file: print ''.join(file.readlines()[52:55])"
wsgiref==0.1.2
xlrd==0.9.2
xlwt==0.7.5

git status shows modifications, git checkout -- <file> doesn't remove them

Another solution that may work for people, since none of the text options worked for me:

Replace the content of .gitattributes with a single line: * binary. This tells git to treat every file as a binary file that it can't do anything with.
Check that message for the offending files is gone; if it's not you can git checkout -- <files> to restore them to the repository version
git checkout -- .gitattributes to restore the .gitattributes file to its initial state
Check that the files are still not marked as changed.

What's the best way to generate a UML diagram from Python source code?

If you use eclipse, maybe PyUML. Haven't used it, though.

What is /dev/null 2>&1?

I use >> /dev/null 2>&1 for a silent cronjob. A cronjob will do the job, but not send a report to my email.

As far as I know, don't remove /dev/null. It's useful, especially when you run cPanel, it can be used for throw-away cronjob reports.

What is the maximum possible length of a query string?

Different web stacks do support different lengths of http-requests. I know from experience that the early stacks of Safari only supported 4000 characters and thus had difficulty handling ASP.net pages because of the USER-STATE. This is even for POST, so you would have to check the browser and see what the stack limit is. I think that you may reach a limit even on newer browsers. I cannot remember but one of them (IE6, I think) had a limit of 16-bit limit, 32,768 or something.

Line Break in XML formatting?

Take note: I have seen other posts that say 
 will give you a paragraph break, which oddly enough works in the Android xml String.xml file, but will NOT show up in a device when testing (no breaks at all show up). Therefore, the \n shows up on both.

What is the difference between a .cpp file and a .h file?

I know the difference between a declaration and a definition.

Whereas:

A CPP file includes the definitions from any header which it includes (because CPP and header file together become a single 'translation unit')
A header file might be included by more than one CPP file
The linker typically won't like anything defined in more than one CPP file

Therefore any definitions in a header file should be inline or static. Header files also contain declarations which are used by more than one CPP file.

Definitions that are neither static nor inline are placed in CPP files. Also, any declarations that are only needed within one CPP file are often placed within that CPP file itself, nstead of in any (sharable) header file.

How to fast get Hardware-ID in C#?

The following approach was inspired by this answer to a related (more general) question.

The approach is to read the MachineGuid value in registry key HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Cryptography. This value is generated during OS installation.

There are few ways around the uniqueness of the Hardware-ID per machine using this approach. One method is editing the registry value, but this would cause complications on the user's machine afterwards. Another method is to clone a drive image which would copy the MachineGuid value.

However, no approach is hack-proof and this will certainly be good enough for normal users. On the plus side, this approach is quick performance-wise and simple to implement.

public string GetMachineGuid()
{
   string location = @"SOFTWARE\Microsoft\Cryptography";
   string name = "MachineGuid";

   using (RegistryKey localMachineX64View = 
       RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry64))
   {
       using (RegistryKey rk = localMachineX64View.OpenSubKey(location))
       {
           if (rk == null)
               throw new KeyNotFoundException(
                   string.Format("Key Not Found: {0}", location));

           object machineGuid = rk.GetValue(name);
           if (machineGuid == null)
               throw new IndexOutOfRangeException(
                   string.Format("Index Not Found: {0}", name));

           return machineGuid.ToString();
       }
   }
}

How to: Create trigger for auto update modified date with SQL Server 2008

My approach:

define a default constraint on the ModDate column with a value of GETDATE() - this handles the INSERT case
have a AFTER UPDATE trigger to update the ModDate column

Something like:

CREATE TRIGGER trg_UpdateTimeEntry
ON dbo.TimeEntry
AFTER UPDATE
AS
    UPDATE dbo.TimeEntry
    SET ModDate = GETDATE()
    WHERE ID IN (SELECT DISTINCT ID FROM Inserted)

What is the iBeacon Bluetooth Profile

If the reason you ask this question is because you want to use Core Bluetooth to advertise as an iBeacon rather than using the standard API, you can easily do so by advertising an NSDictionary such as:

{
    kCBAdvDataAppleBeaconKey = <a7c4c5fa a8dd4ba1 b9a8a240 584f02d3 00040fa0 c5>;
}

See this answer for more information.

Get item in the list in Scala?

Please use parenthesis () to access the list elements list_name(index)

Get Android shared preferences value in activity/normal class

If you have a SharedPreferenceActivity by which you have saved your values

SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(this);
String imgSett = prefs.getString(keyChannel, "");

if the value is saved in a SharedPreference in an Activity then this is the correct way to saving it.

SharedPreferences shared = getSharedPreferences(PREF_NAME, MODE_PRIVATE);
SharedPreferences.Editor editor = shared.edit();
editor.putString(keyChannel, email);
editor.commit();// commit is important here.

and this is how you can retrieve the values.

SharedPreferences shared = getSharedPreferences(PREF_NAME, MODE_PRIVATE);
String channel = (shared.getString(keyChannel, ""));

Also be aware that you can do so in a non-Activity class too but the only condition is that you need to pass the context of the Activity. use this context in to get the SharedPreferences.

mContext.getSharedPreferences(PREF_NAME, MODE_PRIVATE);

Are there any style options for the HTML5 Date picker?

The following eight pseudo-elements are made available by WebKit for customizing a date input’s textbox:

::-webkit-datetime-edit
::-webkit-datetime-edit-fields-wrapper
::-webkit-datetime-edit-text
::-webkit-datetime-edit-month-field
::-webkit-datetime-edit-day-field
::-webkit-datetime-edit-year-field
::-webkit-inner-spin-button
::-webkit-calendar-picker-indicator

So if you thought the date input could use more spacing and a ridiculous color scheme you could add the following:

_x000D_

::-webkit-datetime-edit { padding: 1em; }_x000D_
::-webkit-datetime-edit-fields-wrapper { background: silver; }_x000D_
::-webkit-datetime-edit-text { color: red; padding: 0 0.3em; }_x000D_
::-webkit-datetime-edit-month-field { color: blue; }_x000D_
::-webkit-datetime-edit-day-field { color: green; }_x000D_
::-webkit-datetime-edit-year-field { color: purple; }_x000D_
::-webkit-inner-spin-button { display: none; }_x000D_
::-webkit-calendar-picker-indicator { background: orange; }

_x000D_

<input type="date">

_x000D_

Screenshot

How to uninstall Anaconda completely from macOS

Open the terminal and remove your entire Anaconda directory, which will have a name such as “anaconda2” or “anaconda3”, by entering the following command: rm -rf ~/anaconda3. Then remove conda with command "conda uninstall" https://conda.io/docs/commands/conda-uninstall.html.

Common MySQL fields and their appropriate data types

Someone's going to post a much better answer than this, but just wanted to make the point that personally I would never store a phone number in any kind of integer field, mainly because:

You don't need to do any kind of arithmetic with it, and
Sooner or later someone's going to try to (do something like) put brackets around their area code.

In general though, I seem to almost exclusively use:

INT(11) for anything that is either an ID or references another ID
DATETIME for time stamps
VARCHAR(255) for anything guaranteed to be under 255 characters (page titles, names, etc)
TEXT for pretty much everything else.

Of course there are exceptions, but I find that covers most eventualities.

Autoplay audio files on an iPad with HTML5

I confirm that the audio isn't working as described (at least on iPad running 4.3.5). The specific issue is the audio won't load in an asynchronous method (ajax, timer event, etc) but it will play if it was preloaded. The problem is the load has to be on a user-triggered event. So if you can have a button for the user to initiate the playing you can do something like:

function initSounds() {
    window.sounds = new Object();
    var sound = new Audio('assets/sounds/clap.mp3');
    sound.load();
    window.sounds['clap.mp3'] = sound;
}

Then to play it, eg in an ajax request, you can do

function doSomething() {
    $.post('testReply.php',function(data){
        window.sounds['clap.mp3'].play();
    }); 
}

Not the greatest solution, but it may help, especially knowing the culprit is the load function in a non-user-triggered event.

Edit: I found Apple's explanation, and it affects iOS 4+: http://developer.apple.com/library/safari/#documentation/AudioVideo/Conceptual/Using_HTML5_Audio_Video/Device-SpecificConsiderations/Device-SpecificConsiderations.html

Iterating through a string word by word

This is one way to do it:

string = "this is a string"
ssplit = string.split()
for word in ssplit:
    print (word)

Output:

this
is
a
string

What are some uses of template template parameters?

I use it for versioned types.

If you have a type versioned through a template such as MyType<version>, you can write a function in which you can capture the version number:

template<template<uint8_t> T, uint8_t Version>
Foo(const T<Version>& obj)
{
    assert(Version > 2 && "Versions older than 2 are no longer handled");
    ...
    switch (Version)
    {
    ...
    }
}

So you can do different things depending on the version of the type being passed in instead of having an overload for each type. You can also have conversion functions which take in MyType<Version> and return MyType<Version+1>, in a generic way, and even recurse them to have a ToNewest() function which returns the latest version of a type from any older version (very useful for logs that might have been stored a while back but need to be processed with today's newest tool).

How to sort with a lambda?

Can the problem be with the "a.mProperty > b.mProperty" line? I've gotten the following code to work:

#include <algorithm>
#include <vector>
#include <iterator>
#include <iostream>
#include <sstream>

struct Foo
{
    Foo() : _i(0) {};

    int _i;

    friend std::ostream& operator<<(std::ostream& os, const Foo& f)
    {
        os << f._i;
        return os;
    };
};

typedef std::vector<Foo> VectorT;

std::string toString(const VectorT& v)
{
    std::stringstream ss;
    std::copy(v.begin(), v.end(), std::ostream_iterator<Foo>(ss, ", "));
    return ss.str();
};

int main()
{

    VectorT v(10);
    std::for_each(v.begin(), v.end(),
            [](Foo& f)
            {
                f._i = rand() % 100;
            });

    std::cout << "before sort: " << toString(v) << "\n";

    sort(v.begin(), v.end(),
            [](const Foo& a, const Foo& b)
            {
                return a._i > b._i;
            });

    std::cout << "after sort:  " << toString(v) << "\n";
    return 1;
};

The output is:

before sort: 83, 86, 77, 15, 93, 35, 86, 92, 49, 21,
after sort:  93, 92, 86, 86, 83, 77, 49, 35, 21, 15,

Java converting int to hex and back again

Java's parseInt method is actally a bunch of code eating "false" hex : if you want to translate -32768, you should convert the absolute value into hex, then prepend the string with '-'.

There is a sample of Integer.java file :

public static int parseInt(String s, int radix)

The description is quite explicit :

* Parses the string argument as a signed integer in the radix 
* specified by the second argument. The characters in the string 
...
...
* parseInt("0", 10) returns 0
* parseInt("473", 10) returns 473
* parseInt("-0", 10) returns 0
* parseInt("-FF", 16) returns -255

ConcurrentModificationException for ArrayList

I like a reverse order for loop such as:

int size = list.size();
for (int i = size - 1; i >= 0; i--) {
    if(remove){
        list.remove(i);
    }
}

because it doesn't require learning any new data structures or classes.

good example of Javadoc

ANT for example - source code browsable online: http://svn.apache.org/viewvc/ant/core/trunk/src/main/org/apache/tools/ant/DefaultLogger.java?view=co

To choose other files start from: http://svn.apache.org/viewvc/ant/core/trunk/src/main/org/apache/tools/ant/?pathrev=761528

View markdown files offline

I just installed https://github.com/ypocat/gfms. It does a very good job rendering github flavored markdown. It detects changes in your markdown, so you just put your browser and editor side-by-side. It is Node.js, so it should work fine on any platform.

If you have Node.js is installed, the installation is simple:

sudo npm install -g gfms
gfms --port 9999 (in your project directory)
http://localhost:9999/ (open with any browser)

Android ViewPager with bottom dots

Following is my proposed solution.

Since we need to show only some images in the view pagers so have avoided the cumbersome use of fragments.
- Implemented the view page indicators (the bottom dots without any extra library or plugin)
- On the touch of the view page indicators(the dots) also the page navigation is happening.
- Please don"t forget to add your own images in the resources.
- Feel free to comment and improve upon it.

A) Following is my activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="schneider.carouseladventure.MainActivity">

    <android.support.v4.view.ViewPager xmlns:android="http://schemas.android.com/apk/res/android"
        android:id="@+id/viewpager"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <RelativeLayout
        android:id="@+id/viewPagerIndicator"
        android:layout_width="match_parent"
        android:layout_height="55dp"
        android:layout_alignParentBottom="true"
        android:layout_marginTop="5dp"
        android:gravity="center">

        <LinearLayout
            android:id="@+id/viewPagerCountDots"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_centerHorizontal="true"
            android:gravity="center"
            android:orientation="horizontal" />

    </RelativeLayout>


</RelativeLayout>

B) pager_item.xml

<?xml version="1.0" encoding="utf-8"?>

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

    <ImageView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/imageView" />
</LinearLayout>

C) MainActivity.java

import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class MainActivity extends AppCompatActivity implements ViewPager.OnPageChangeListener, View.OnClickListener {

    int[] mResources = {R.drawable.nature1, R.drawable.nature2, R.drawable.nature3, R.drawable.nature4,
            R.drawable.nature5, R.drawable.nature6
    };

    ViewPager mViewPager;
    private CustomPagerAdapter mAdapter;
    private LinearLayout pager_indicator;
    private int dotsCount;
    private ImageView[] dots;


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

        mViewPager = (ViewPager) findViewById(R.id.viewpager);
        pager_indicator = (LinearLayout) findViewById(R.id.viewPagerCountDots);
        mAdapter = new CustomPagerAdapter(this, mResources);
        mViewPager.setAdapter(mAdapter);
        mViewPager.setCurrentItem(0);
        mViewPager.setOnPageChangeListener(this);

        setPageViewIndicator();

    }

    private void setPageViewIndicator() {

        Log.d("###setPageViewIndicator", " : called");
        dotsCount = mAdapter.getCount();
        dots = new ImageView[dotsCount];

        for (int i = 0; i < dotsCount; i++) {
            dots[i] = new ImageView(this);
            dots[i].setImageDrawable(getResources().getDrawable(R.drawable.nonselecteditem_dot));

            LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
                    LinearLayout.LayoutParams.WRAP_CONTENT,
                    LinearLayout.LayoutParams.WRAP_CONTENT
            );

            params.setMargins(4, 0, 4, 0);

            final int presentPosition = i;
            dots[presentPosition].setOnTouchListener(new View.OnTouchListener() {

                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    mViewPager.setCurrentItem(presentPosition);
                    return true;
                }

            });


            pager_indicator.addView(dots[i], params);
        }

        dots[0].setImageDrawable(getResources().getDrawable(R.drawable.selecteditem_dot));
    }

    @Override
    public void onClick(View v) {

    }

    @Override
    public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

    }

    @Override
    public void onPageSelected(int position) {

        Log.d("###onPageSelected, pos ", String.valueOf(position));
        for (int i = 0; i < dotsCount; i++) {
            dots[i].setImageDrawable(getResources().getDrawable(R.drawable.nonselecteditem_dot));
        }

        dots[position].setImageDrawable(getResources().getDrawable(R.drawable.selecteditem_dot));

        if (position + 1 == dotsCount) {

        } else {

        }
    }

    @Override
    public void onPageScrollStateChanged(int state) {

    }
}

D) CustomPagerAdapter.java

 import android.content.Context;
    import android.support.v4.view.PagerAdapter;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.ImageView;
    import android.widget.LinearLayout;

    public class CustomPagerAdapter extends PagerAdapter {
        private Context mContext;
        LayoutInflater mLayoutInflater;
        private int[] mResources;

        public CustomPagerAdapter(Context context, int[] resources) {
            mContext = context;
            mLayoutInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            mResources = resources;
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {

            View itemView = mLayoutInflater.inflate(R.layout.pager_item,container,false);
            ImageView imageView = (ImageView) itemView.findViewById(R.id.imageView);
            imageView.setImageResource(mResources[position]);
           /* LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(950, 950);
            imageView.setLayoutParams(layoutParams);*/
            container.addView(itemView);
            return itemView;
        }

        @Override
        public void destroyItem(ViewGroup collection, int position, Object view) {
            collection.removeView((View) view);
        }

        @Override
        public int getCount() {
            return mResources.length;
        }

        @Override
        public boolean isViewFromObject(View view, Object object) {
            return view == object;
        }
    }

E) selecteditem_dot.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval" android:useLevel="true"
    android:dither="true">

    <size android:height="12dip" android:width="12dip"/>

    <solid android:color="#7e7e7e"/>
</shape>

F) nonselecteditem_dot.xml

 <?xml version="1.0" encoding="utf-8"?>
    <shape xmlns:android="http://schemas.android.com/apk/res/android"
        android:shape="oval" android:useLevel="true"
        android:dither="true">        
        <size android:height="12dip" android:width="12dip"/>        
        <solid android:color="#d3d3d3"/>
    </shape>

System.loadLibrary(...) couldn't find native library in my case

In gradle, after copying all files folders to libs/

jniLibs.srcDirs = ['libs']

Adding the above line to sourceSets in build.gradle file worked. Nothing else worked whatsoever.

How to validate a credit card number

This works: http://jsfiddle.net/WHKeK/

function validate_creditcardnumber()
{
    var re16digit=/^\d{16}$/
    if (document.myform.CreditCardNumber.value.search(re16digit) == -1)
        alert("Please enter your 16 digit credit card numbers");
    return false;    
}

You have a typo. You call the variable re16digit, but in your search you have re10digit.

Count how many rows have the same value

Use this query this will give your output:

select 
  t.name
  ,( select 
       count (*) as num_value 
     from Table 
      where num =t.num) cnt 
from Table t;

Python: printing a file to stdout

Sure. Assuming you have a string with the file's name called fname, the following does the trick.

with open(fname, 'r') as fin:
    print(fin.read())

Better way to cast object to int

Maybe Convert.ToInt32.

Watch out for exception, in both cases.

What is the default maximum heap size for Sun's JVM from Java SE 6?

one way is if you have a jdk installed , in bin folder there is a utility called jconsole(even visualvm can be used). Launch it and connect to the relevant java process and you can see what are the heap size settings set and many other details

When running headless or cli only, jConsole can be used over lan, if you specify a port to connect on when starting the service in question.

How to insert tab character when expandtab option is on in Vim

You can use <CTRL-V><Tab> in "insert mode". In insert mode, <CTRL-V> inserts a literal copy of your next character.

If you need to do this often, @Dee`Kej suggested (in the comments) setting Shift+Tab to insert a real tab with this mapping:

:inoremap <S-Tab> <C-V><Tab>

Also, as noted by @feedbackloop, on Windows you may need to press <CTRL-Q> rather than <CTRL-V>.

Why do python lists have pop() but not push()

Push and Pop make sense in terms of the metaphor of a stack of plates or trays in a cafeteria or buffet, specifically the ones in type of holder that has a spring underneath so the top plate is (more or less... in theory) in the same place no matter how many plates are under it.

If you remove a tray, the weight on the spring is a little less and the stack "pops" up a little, if you put the plate back, it "push"es the stack down. So if you think about the list as a stack and the last element as being on top, then you shouldn't have much confusion.

Objective-C : BOOL vs bool

From the definition in objc.h:

#if (TARGET_OS_IPHONE && __LP64__)  ||  TARGET_OS_WATCH
typedef bool BOOL;
#else
typedef signed char BOOL; 
// BOOL is explicitly signed so @encode(BOOL) == "c" rather than "C" 
// even if -funsigned-char is used.
#endif

#define YES ((BOOL)1)
#define NO  ((BOOL)0)

So, yes, you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.

How to add an action to a UIAlertView button using Swift iOS

func showAlertAction(title: String, message: String){
    let alert = UIAlertController(title: title, message: message, preferredStyle: UIAlertController.Style.alert)
    alert.addAction(UIAlertAction(title: "Ok", style: UIAlertAction.Style.default, handler: {(action:UIAlertAction!) in
        print("Action")
    }))
    alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertAction.Style.default, handler: nil))
    self.present(alert, animated: true, completion: nil)
}

Delete a row in DataGridView Control in VB.NET

If dgv(11, dgv.CurrentRow.Index).Selected = True Then
    dgv.Rows.RemoveAt(dgv.CurrentRow.Index)
Else
    Exit Sub
End If

Static nested class in Java, why?

I don't know about performance difference, but as you say, static nested class is not a part of an instance of the enclosing class. Seems just simpler to create a static nested class unless you really need it to be an inner class.

It's a bit like why I always make my variables final in Java - if they're not final, I know there's something funny going on with them. If you use an inner class instead of a static nested class, there should be a good reason.

notifyDataSetChanged not working on RecyclerView

In your parseResponse() you are creating a new instance of the BusinessAdapter class, but you aren't actually using it anywhere, so your RecyclerView doesn't know the new instance exists.

You either need to:

Call recyclerView.setAdapter(mBusinessAdapter) again to update the RecyclerView's adapter reference to point to your new one
Or just remove mBusinessAdapter = new BusinessAdapter(mBusinesses); to continue using the existing adapter. Since you haven't changed the mBusinesses reference, the adapter will still use that array list and should update correctly when you call notifyDataSetChanged().

How do I prevent the error "Index signature of object type implicitly has an 'any' type" when compiling typescript with noImplicitAny flag enabled?

The following tsconfig setting will allow you to ignore these errors - set it to true.

suppressImplicitAnyIndexErrors

Suppress noImplicitAny errors for indexing objects lacking index signatures.

Div vertical scrollbar show

What browser are you testing in?

What DOCType have you set?

How exactly are you declaring your CSS?

Are you sure you haven't missed a ; before/after the overflow-y: scroll?

I've just tested the following in IE7 and Firefox and it works fine

_x000D_

<!-- Scroll bar present but disabled when less content -->_x000D_
<div style="width: 200px; height: 100px; overflow-y: scroll;">_x000D_
  test_x000D_
</div>_x000D_
_x000D_
<!-- Scroll bar present and enabled when more contents -->        _x000D_
<div style="width: 200px; height: 100px; overflow-y: scroll;">_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
  test<br />_x000D_
</div>

_x000D_

Error: No default engine was specified and no extension was provided

Just set view engine in your code.

var app = express(); 
app.set('view engine', 'ejs');

pod has unbound PersistentVolumeClaims

You have to define a PersistentVolume providing disc space to be consumed by the PersistentVolumeClaim.

When using storageClass Kubernetes is going to enable "Dynamic Volume Provisioning" which is not working with the local file system.

To solve your issue:

Provide a PersistentVolume fulfilling the constraints of the claim (a size >= 100Mi)
Remove the storageClass-line from the PersistentVolumeClaim
Remove the StorageClass from your cluster

How do these pieces play together?

At creation of the deployment state-description it is usually known which kind (amount, speed, ...) of storage that application will need.
To make a deployment versatile you'd like to avoid a hard dependency on storage. Kubernetes' volume-abstraction allows you to provide and consume storage in a standardized way.

The PersistentVolumeClaim is used to provide a storage-constraint alongside the deployment of an application.

The PersistentVolume offers cluster-wide volume-instances ready to be consumed ("bound"). One PersistentVolume will be bound to one claim. But since multiple instances of that claim may be run on multiple nodes, that volume may be accessed by multiple nodes.

A PersistentVolume without StorageClass is considered to be static.

"Dynamic Volume Provisioning" alongside with a StorageClass allows the cluster to provision PersistentVolumes on demand. In order to make that work, the given storage provider must support provisioning - this allows the cluster to request the provisioning of a "new" PersistentVolume when an unsatisfied PersistentVolumeClaim pops up.

Example PersistentVolume

In order to find how to specify things you're best advised to take a look at the API for your Kubernetes version, so the following example is build from the API-Reference of K8S 1.17:

apiVersion: v1
kind: PersistentVolume
metadata:
  name: ckan-pv-home
  labels:
    type: local
spec:
  capacity:
    storage: 100Mi
  hostPath:
    path: "/mnt/data/ckan"

The PersistentVolumeSpec allows us to define multiple attributes. I chose a hostPath volume which maps a local directory as content for the volume. The capacity allows the resource scheduler to recognize this volume as applicable in terms of resource needs.

Additional Resources:

Configure PersistentVolume Guide

Importing class/java files in Eclipse

create a new java project in Eclipse and copy .java files to its src directory, if you don't know where those source files should be placed, right click on the root of the project and choose new->class to create a test class and see where its .java file is placed, then put other files with it, in the same directory, you may have to adjust the package in those source files according to the new project directory structure.

if you use external libraries in your code, you have two options: either copy / download jar files or use maven if you use maven you'll have to create the project at maven project in the first place, creating java projects as maven projects are the way to go anyway but that's for another post...

dlib installation on Windows 10

Install Dlib from .whl

Dlib 19.7.0

pip install https://pypi.python.org/packages/da/06/bd3e241c4eb0a662914b3b4875fc52dd176a9db0d4a2c915ac2ad8800e9e/dlib-19.7.0-cp36-cp36m-win_amd64.whl#md5=b7330a5b2d46420343fbed5df69e6a3f

You can test it, downloading an example from the site, for example SVM_Binary_Classifier.py and running it on your machine.

Note: if this message occurs you have to build dlib from source:

dlib-19.7.0-cp36-cp36m-win_amd64.whl is not a supported wheel on this platform

Install Dlib from source (If the solution above doesn't work)

Windows Dlib > 19.7.0

Download the CMake installer and install it: https://cmake.org/download/
Add CMake executable path to the Enviroment Variables:

set PATH="%PATH%;C:\Program Files\CMake\bin"

note: The path of the executable could be different from C:\Program Files\CMake\bin, just set the PATH accordingly.

note: The path will be set temporarily, to make the change permanent you have to set it in the “Advanced system settings” ? “Environment Variables” tab.
Restart The Cmd or PowerShell window for changes to take effect.
Download the Dlib source(.tar.gz) from the Python Package Index : https://pypi.org/project/dlib/#files extract it and enter into the folder.
Check the Python version: python -V. This is my output: Python 3.7.2 so I'm installing it for Python3.x and not for Python2.x

note: You can install it for both Python 2 and Python 3, if you have set different variables for different binaries i.e: python2 -V, python3 -V
Run the installation: python setup.py install

Linux Dlib 19.17.0

sudo apt-get install cmake

wget https://files.pythonhosted.org/packages/05/57/e8a8caa3c89a27f80bc78da39c423e2553f482a3705adc619176a3a24b36/dlib-19.17.0.tar.gz

tar -xvzf dlib-19.17.0.tar.gz

cd dlib-19.17.0/

sudo python3 setup.py install

note: To install Dlib for Python 2.x use python instead of python3 you can check your python version via python -V

What is the PostgreSQL equivalent for ISNULL()

Create the following function

CREATE OR REPLACE FUNCTION isnull(text, text) RETURNS text AS 'SELECT (CASE (SELECT $1 "
    "is null) WHEN true THEN $2 ELSE $1 END) AS RESULT' LANGUAGE 'sql'

And it'll work.

You may to create different versions with different parameter types.

TypeError: $.browser is undefined

I placed the following html in my code and this cleared up the $.browser error

<script src="http://code.jquery.com/jquery-migrate-1.0.0.js"></script>

Hope this helps u

How to convert Integer to int?

Since you say you're using Java 5, you can use setInt with an Integer due to autounboxing: pstmt.setInt(1, tempID) should work just fine. In earlier versions of Java, you would have had to call .intValue() yourself.

The opposite works as well... assigning an int to an Integer will automatically cause the int to be autoboxed using Integer.valueOf(int).

Groovy - Convert object to JSON string

Do you mean like:

import groovy.json.*

class Me {
    String name
}

def o = new Me( name: 'tim' )

println new JsonBuilder( o ).toPrettyString()

git: fatal: Could not read from remote repository

I have tried everything including generating new key, adding to the GitHub account, editing .ssh/config and .git/config. But still it was giving me the same error. Then I tried following command and it does work successfully.

ssh-agent bash -c 'ssh-add ~/.ssh/id_rsa; git clone [email protected]:username/repo.git'

How to move all HTML element children to another parent using JavaScript?

This answer only really works if you don't need to do anything other than transferring the inner code (innerHTML) from one to the other:

// Define old parent
var oldParent = document.getElementById('old-parent');

// Define new parent
var newParent = document.getElementById('new-parent');

// Basically takes the inner code of the old, and places it into the new one
newParent.innerHTML = oldParent.innerHTML;

// Delete / Clear the innerHTML / code of the old Parent
oldParent.innerHTML = '';

Hope this helps!

Visual Studio 2017 - Git failed with a fatal error

In my case I didn't have to do anything so drastic as uninstalling Git as per some of the answers here; I just had to use the command line instead of Visual Studio.

Open up cmd at your solution's root and enter:

git pull

You will then be told exactly what the issue is. In my case it told me that I had uncommitted changes that would have been overwritten and that I needed to commit them before I could continue.

Once I had done this the pull succeeded, and I could resolve the conflict in the merge tool.

TLDR

Use the command line instead of Visual Studio to get a more complete error message.

Waiting for Target Device to Come Online

I've had the same problem (AVD not coming online) in a Linux system. In my case, I have solved it setting this environment variable:

$ export ANDROID_EMULATOR_USE_SYSTEM_LIBS = 1

This case is documented here: https://developer.android.com/studio/command-line/variables.html#studio_jdk

Callback functions in Java

If you mean somthing like .NET anonymous delegate, I think Java's anonymous class can be used as well.

public class Main {

    public interface Visitor{
        int doJob(int a, int b);
    }


    public static void main(String[] args) {
        Visitor adder = new Visitor(){
            public int doJob(int a, int b) {
                return a + b;
            }
        };

        Visitor multiplier = new Visitor(){
            public int doJob(int a, int b) {
                return a*b;
            }
        };

        System.out.println(adder.doJob(10, 20));
        System.out.println(multiplier.doJob(10, 20));

    }
}

Is there a way I can retrieve sa password in sql server 2005

MSSQL have its own database management tool called as "MSSQL Server Management Studio (SSMS)". Here are steps to reset SA password using SSMS :

1] Open SSMS management console, it will prompt for authentication details,

Select Server Type : "Database Engine", Server name : IP / hostname of your MSSQL server Authentication : Windows Authentication

Once you select Authentication type as "Windows Authentication", the user name and password fields will be grayed out and it will allow you to login SQL server without entering login details. Windows Authentication is possible only when you are logged on same server in RDP on which SQL service is present.

2] once you are in, under "Object Explorer" expand Security and then Logins 3] locate and right click on user SA and select Properties 4] under General section enter desired password in front of "Password:" and "Confirm Password:" 5] hit OK at bottom.

This is the easiest and secure way to reset SA password instead of using any third party non secure tools

AppSettings get value from .config file

Or you can either use

string value = system.configuration.ConfigurationManager.AppSettings.Get("ClientsFilePath");

//Gets the values associated with the specified key from the System.Collections.Specialized.NameValueCollection

List of Timezone IDs for use with FindTimeZoneById() in C#?

DateTime dt;
TimeZoneInfo tzf;
tzf = TimeZoneInfo.FindSystemTimeZoneById("TimeZone String");
dt = TimeZoneInfo.ConvertTime(DateTime.Now, tzf);
lbltime.Text = dt.ToString();

Can Windows Containers be hosted on linux?

Update3: 06.2019 Some of the comments says that the answer is not clear, I'll try to clarify.

TL;DR:

Q: Can Windows containers run on Linux?

A: No. They cannot. Containers are using the underlying Operating System resources and drivers, so Windows containers can run on Windows only, and Linux containers can run on Linux only.

Q: But what about Docker for Windows? Or other VM-based solutions?

A: Docker for Windows allows you to simulate running Linux containers on Windows, but under the hood a Linux VM is created, so still Linux containers are running on Linux, and Windows containers are running on Windows.

Bonus: Read this very nice article about running Linux docker containers on Windows.

Q: So, what should I do with a .Net Framework 462 app, if I would like to run in a container?

A: It depends. Following several recommendations:

If it is possible - move to .Net Core. Since .Net Core brings support to most major features of .Net Framework, and .Net Framework 4.8 will be the last version of .Net framework
If you cannot migrate to .Net Core - As @Sebastian mentioned - you can convert your libraries to .Net Standard, and have 2 versions of app - one on .Net Framework 4.6.2, and one on .Net Core - it is not always obvious, Visual Studio supports it pretty well (with multi-targeting), but some dependencies can require extra care.
(Less recommended) In some cases, you can run windows containers. Windows containers are becoming more and more mature, with better support in platforms like Kubernetes. But to be able to run .Net Framework code, you still need to run on base image of "Server Core", which occupies about 1.4 GB. In same rare cases, you can migrate your code to .Net Core, but still run on Windows Nano servers, with an image size of 95 MB.

Leaving also the old updates for history

Update2: 08.2018 If you are using Docker-for-Windows, you can run now both windows and linux containers simultaneously: https://blogs.msdn.microsoft.com/premier_developer/2018/04/20/running-docker-windows-and-linux-containers-simultaneously/

Bonus: Not directly related to the question, but you can now run not only the linux container itself, but also orchestrator like kubernetes: https://blog.docker.com/2018/07/kubernetes-is-now-available-in-docker-desktop-stable-channel/

Updated at 2018:

Original answer in general is right, BUT several months ago, docker added experimental feature LCOW (official github repository).

From this post:

Doesn’t Docker for Windows already run Linux containers? That’s right. Docker for Windows can run Linux or Windows containers, with support for Linux containers via a Hyper-V Moby Linux VM (as of Docker for Windows 17.10 this VM is based on LinuxKit).

The setup for running Linux containers with LCOW is a lot simpler than the previous architecture where a Hyper-V Linux VM runs a Linux Docker daemon, along with all your containers. With LCOW, the Docker daemon runs as a Windows process (same as when running Docker Windows containers), and every time you start a Linux container Docker launches a minimal Hyper-V hypervisor running a VM with a Linux kernel, runc and the container processes running on top.

Because there’s only one Docker daemon, and because that daemon now runs on Windows, it will soon be possible to run Windows and Linux Docker containers side-by-side, in the same networking namespace. This will unlock a lot of exciting development and production scenarios for Docker users on Windows.

Original:

As mentioned in comments by @PanagiotisKanavos, containers are not for virtualization, and they are using the resources of the host machine. As a result, for now windows container cannot run "as-is" on linux machine.

But - you can do it by using VM - as it works on windows. You can install windows VM on your linux host, which will allow to run windows containers.

With it, IMHO run it this way on PROD environment will not be the best idea.

Also, this answer provides more details.

Jquery and HTML FormData returns "Uncaught TypeError: Illegal invocation"

In my case, there was a mistake in the list of the parameters was not well formed. So make sure the parameters are well formed. For e.g. correct format of parameters

data: {'reporter': reporter,'partner': partner,'product': product}

Make a directory and copy a file

You can use the shell for this purpose.

Set shl = CreateObject("WScript.Shell") 
shl.Run "cmd mkdir YourDir" & copy "

crop text too long inside div

Why not use relative units?

.cropText {
    max-width: 20em;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

Numpy, multiply array with scalar

You can multiply numpy arrays by scalars and it just works.

>>> import numpy as np
>>> np.array([1, 2, 3]) * 2
array([2, 4, 6])
>>> np.array([[1, 2, 3], [4, 5, 6]]) * 2
array([[ 2,  4,  6],
       [ 8, 10, 12]])

This is also a very fast and efficient operation. With your example:

>>> a_1 = np.array([1.0, 2.0, 3.0])
>>> a_2 = np.array([[1., 2.], [3., 4.]])
>>> b = 2.0
>>> a_1 * b
array([2., 4., 6.])
>>> a_2 * b
array([[2., 4.],
       [6., 8.]])

Check for file exists or not in sql server?

Not tested but you can try something like this :

Declare @count as int
Set @count=1
Declare @inputFile varchar(max)
Declare @Sample Table
(id int,filepath varchar(max) ,Isexists char(3))

while @count<(select max(id) from yourTable)
BEGIN
Set @inputFile =(Select filepath from yourTable where id=@count)
DECLARE @isExists INT
exec master.dbo.xp_fileexist @inputFile , 
@isExists OUTPUT
insert into @Sample
Select @count,@inputFile ,case @isExists 
when 1 then 'Yes' 
else 'No' 
end as isExists
set @count=@count+1
END

Tomcat is not deploying my web project from Eclipse

I have this similar problem where I'm able to start the tomcat server but however application not initialized or started, so I have Right clicked on my project --> Deployment Assembly --> Click 'Add' in the right side panel, select 'Java Build path entries' and click 'Next', Now select 'Maven dependencies' and click 'Finish'. Now I run the server and it started the application successfully.

What is a user agent stylesheet?

Each browser provides a default stylesheet, called the user agent stylesheet, in case an HTML file does not specify one. Styles that you specify override the defaults.

Because you have not specified values for the table element’s box, the default styles have been applied.

What does the term "canonical form" or "canonical representation" in Java mean?

I believe there are two related uses of canonical: forms and instances.

A canonical form means that values of a particular type of resource can be described or represented in multiple ways, and one of those ways is chosen as the favored canonical form. (That form is canonized, like books that made it into the bible, and the other forms are not.) A classic example of a canonical form is paths in a hierarchical file system, where a single file can be referenced in a number of ways:

myFile.txt                                   # in current working dir
../conf/myFile.txt                           # relative to the CWD
/apps/tomcat/conf/myFile.txt                 # absolute path using symbolic links
/u1/local/apps/tomcat-5.5.1/conf/myFile.txt  # absolute path with no symlinks

The classic definition of the canonical representation of that file would be the last path. With local or relative paths you cannot globally identify the resource without contextual information. With absolute paths you can identify the resource, but cannot tell if two paths refer to the same entity. With two or more paths converted to their canonical forms, you can do all the above, plus determine if two resources are the same or not, if that is important to your application (solve the aliasing problem).

Note that the canonical form of a resource is not a quality of that particular form itself; there can be multiple possible canonical forms for a given type like file paths (say, lexicographically first of all possible absolute paths). One form is just selected as the canonical form for a particular application reason, or maybe arbitrarily so that everyone speaks the same language.

Forcing objects into their canonical instances is the same basic idea, but instead of determining one "best" representation of a resource, it arbitrarily chooses one instance of a class of instances with the same "content" as the canonical reference, then converts all references to equivalent objects to use the one canonical instance.

This can be used as a technique for optimizing both time and space. If there are multiple instances of equivalent objects in an application, then by forcing them all to be resolved as the single canonical instance of a particular value, you can eliminate all but one of each value, saving space and possibly time since you can now compare those values with reference identity (==) as opposed to object equivalence (equals() method).

A classic example of optimizing performance with canonical instances is collapsing strings with the same content. Calling String.intern() on two strings with the same character sequence is guaranteed to return the same canonical String object for that text. If you pass all your strings through that canonicalizer, you know equivalent strings are actually identical object references, i.e., aliases

The enum types in Java 5.0+ force all instances of a particular enum value to use the same canonical instance within a VM, even if the value is serialized and deserialized. That is why you can use if (day == Days.SUNDAY) with impunity in java if Days is an enum type. Doing this for your own classes is certainly possible, but takes care. Read Effective Java by Josh Bloch for details and advice.

ASP.NET MVC 404 Error Handling

Looks like this is the best way to catch everything.

How can I properly handle 404 in ASP.NET MVC?

Android: ProgressDialog.show() crashes with getApplicationContext

if you have a problem on groupActivity dont use this. PARENT is a static from the Parent ActivityGroup.

final AlertDialog.Builder builder = new AlertDialog.Builder(GroupActivityParent.PARENT);

instead of

final AlertDialog.Builder builder = new AlertDialog.Builder(getParent());

Use images instead of radio buttons

Images can be placed in place of radio buttons by using label and span elements.

   <div class="customize-radio">
        <label>Favourite Smiley</label><br>
        <label for="hahaha">
        <input type="radio" name="smiley" id="hahaha">
        <span class="haha-img"></span>
        HAHAHA
        </label>
        <label for="kiss">
        <input type="radio" name="smiley" id="kiss">
        <span class="kiss-img"></span>
        Kiss
        </label>
        <label for="tongueOut">
        <input type="radio" name="smiley" id="tongueOut">
        <span class="tongueout-img"></span>
        TongueOut
        </label>
    </div>

Radio button should be hidden,

.customize-radio label > input[type = 'radio'] {
    visibility: hidden;
    position: absolute;
}

Image can be given in the span tag,

.customize-radio label > input[type = 'radio'] ~ span{
    cursor: pointer;
    width: 27px;
    height: 24px;
    display: inline-block;
    background-size: 27px 24px;
    background-repeat: no-repeat;
}
.haha-img {
    background-image: url('hahabefore.png');
}

.kiss-img{
    background-image: url('kissbefore.png');
}
.tongueout-img{
    background-image: url('tongueoutbefore.png');
}

To change the image on click of radio button, add checked state to the input tag,

.customize-radio label > input[type = 'radio']:checked ~ span.haha-img{
     background-image: url('haha.png');
}
.customize-radio label > input[type = 'radio']:checked ~ span.kiss-img{
    background-image: url('kiss.png');
}
.customize-radio label > input[type = 'radio']:checked ~ span.tongueout-img{
        background-image: url('tongueout.png');
}

If you have any queries, Refer to the following link, As I have taken solution from the below blog, http://frontendsupport.blogspot.com/2018/06/cool-radio-buttons-with-images.html

Which regular expression operator means 'Don't' match this character?

^ used at the beginning of a character range, or negative lookahead/lookbehind assertions.

>>> re.match('[^f]', 'foo')
>>> re.match('[^f]', 'bar')
<_sre.SRE_Match object at 0x7f8b102ad6b0>
>>> re.match('(?!foo)...', 'foo')
>>> re.match('(?!foo)...', 'bar')
<_sre.SRE_Match object at 0x7f8b0fe70780>

Why does git perform fast-forward merges by default?

Fast-forward merging makes sense for short-lived branches, but in a more complex history, non-fast-forward merging may make the history easier to understand, and make it easier to revert a group of commits.

Warning: Non-fast-forwarding has potential side effects as well. Please review https://sandofsky.com/blog/git-workflow.html, avoid the 'no-ff' with its "checkpoint commits" that break bisect or blame, and carefully consider whether it should be your default approach for master.

alt text
^{(From nvie.com, Vincent Driessen, post "A successful Git branching model")}

Incorporating a finished feature on develop

Finished features may be merged into the develop branch to add them to the upcoming release:

$ git checkout develop
Switched to branch 'develop'
$ git merge --no-ff myfeature
Updating ea1b82a..05e9557
(Summary of changes)
$ git branch -d myfeature
Deleted branch myfeature (was 05e9557).
$ git push origin develop

The --no-ff flag causes the merge to always create a new commit object, even if the merge could be performed with a fast-forward. This avoids losing information about the historical existence of a feature branch and groups together all commits that together added the feature.

Jakub Narebski also mentions the config merge.ff:

By default, Git does not create an extra merge commit when merging a commit that is a descendant of the current commit. Instead, the tip of the current branch is fast-forwarded.
When set to false, this variable tells Git to create an extra merge commit in such a case (equivalent to giving the --no-ff option from the command line).
When set to 'only', only such fast-forward merges are allowed (equivalent to giving the --ff-only option from the command line).

The fast-forward is the default because:

short-lived branches are very easy to create and use in Git
short-lived branches often isolate many commits that can be reorganized freely within that branch
those commits are actually part of the main branch: once reorganized, the main branch is fast-forwarded to include them.

But if you anticipate an iterative workflow on one topic/feature branch (i.e., I merge, then I go back to this feature branch and add some more commits), then it is useful to include only the merge in the main branch, rather than all the intermediate commits of the feature branch.

In this case, you can end up setting this kind of config file:

[branch "master"]
# This is the list of cmdline options that should be added to git-merge 
# when I merge commits into the master branch.

# The option --no-commit instructs git not to commit the merge
# by default. This allows me to do some final adjustment to the commit log
# message before it gets commited. I often use this to add extra info to
# the merge message or rewrite my local branch names in the commit message
# to branch names that are more understandable to the casual reader of the git log.

# Option --no-ff instructs git to always record a merge commit, even if
# the branch being merged into can be fast-forwarded. This is often the
# case when you create a short-lived topic branch which tracks master, do
# some changes on the topic branch and then merge the changes into the
# master which remained unchanged while you were doing your work on the
# topic branch. In this case the master branch can be fast-forwarded (that
# is the tip of the master branch can be updated to point to the tip of
# the topic branch) and this is what git does by default. With --no-ff
# option set, git creates a real merge commit which records the fact that
# another branch was merged. I find this easier to understand and read in
# the log.

mergeoptions = --no-commit --no-ff

The OP adds in the comments:

I see some sense in fast-forward for [short-lived] branches, but making it the default action means that git assumes you... often have [short-lived] branches. Reasonable?

Jefromi answers:

I think the lifetime of branches varies greatly from user to user. Among experienced users, though, there's probably a tendency to have far more short-lived branches.

To me, a short-lived branch is one that I create in order to make a certain operation easier (rebasing, likely, or quick patching and testing), and then immediately delete once I'm done.
That means it likely should be absorbed into the topic branch it forked from, and the topic branch will be merged as one branch. No one needs to know what I did internally in order to create the series of commits implementing that given feature.

More generally, I add:

it really depends on your development workflow:

if it is linear, one branch makes sense.

If you need to isolate features and work on them for a long period of time and repeatedly merge them, several branches make sense.

See "When should you branch?"

Actually, when you consider the Mercurial branch model, it is at its core one branch per repository (even though you can create anonymous heads, bookmarks and even named branches)
See "Git and Mercurial - Compare and Contrast".

Mercurial, by default, uses anonymous lightweight codelines, which in its terminology are called "heads".
Git uses lightweight named branches, with injective mapping to map names of branches in remote repository to names of remote-tracking branches.
Git "forces" you to name branches (well, with the exception of a single unnamed branch, which is a situation called a "detached HEAD"), but I think this works better with branch-heavy workflows such as topic branch workflow, meaning multiple branches in a single repository paradigm.

How to set underline text on textview?

In my sign_in.xml file I used this:

<Button
    android:id="@+id/signuptextlinkbtn"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_marginTop="10dp"
    android:background="@android:color/transparent"
    android:onClick="performSingUpMethod"
    android:text="Sign up now!"
    android:textColor="#5B55FF"
    android:textSize="15dp"
    android:textStyle="bold" />

In my SignIn.java file, I used this:

import android.graphics.Paint;
Button signuptextlinkbutton = (Button) findViewById(R.id.signuptextlinkbtn);
signuptextlinkbutton.setPaintFlags(signuptextlinkbutton.getPaintFlags()| Paint.UNDERLINE_TEXT_FLAG);

Now I can see my link underlined. It was simply text even thought I declared it as a Button.

Unused arguments in R

One approach (which I can't imagine is good programming practice) is to add the ... which is traditionally used to pass arguments specified in one function to another.

> multiply <- function(a,b) a*b
> multiply(a = 2,b = 4,c = 8)
Error in multiply(a = 2, b = 4, c = 8) : unused argument(s) (c = 8)
> multiply2 <- function(a,b,...) a*b
> multiply2(a = 2,b = 4,c = 8)
[1] 8

You can read more about ... is intended to be used here

Concatenate chars to form String in java

If the size of the string is fixed, you might find easier to use an array of chars. If you have to do this a lot, it will be a tiny bit faster too.

char[] chars = new char[3];
chars[0] = 'i';
chars[1] = 'c';
chars[2] = 'e';
return new String(chars);

Also, I noticed in your original question, you use the Char class. If your chars are not nullable, it is better to use the lowercase char type.

Android Studio does not show layout preview

This problem occurs due to theme compatibility issue. All you have to do is first navigate to res/values/styles.xml in the project view.There look for base application theme which by default should be the fourth line. It'd look similar to the following:

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">

Now, you just have to add 'Base. to the parent.

<style name="AppTheme" parent="Base.Theme.AppCompat.Light.DarkActionBar">

Undefined class constant 'MYSQL_ATTR_INIT_COMMAND' with pdo

I got this error this morning, I just did a fresh install of Fedora 14 and was trying to get my local projects back online. I was missing php-mysql, I installed it via yum and the error is now gone.

Google Maps API v3: How do I dynamically change the marker icon?

This thread might be dead, but StyledMarker is available for API v3. Just bind the color change you want to the correct DOM event using the addDomListener() method. This example is pretty close to what you want to do. If you look at the page source, change:

google.maps.event.addDomListener(document.getElementById("changeButton"),"click",function() {
  styleIcon.set("color","#00ff00");
  styleIcon.set("text","Go");
});

to something like:

google.maps.event.addDomListener("mouseover",function() {
  styleIcon.set("color","#00ff00");
  styleIcon.set("text","Go");
});

That should be enough to get you moving along.

The Wikipedia page on DOM Events will also help you target the event that you want to capture on the client-side.

Good luck (if you still need it)

Cross-browser custom styling for file upload button

Any easy way to cover ALL file inputs is to just style your input[type=button] and drop this in globally to turn file inputs into buttons:

$(document).ready(function() {
    $("input[type=file]").each(function () {
        var thisInput$ = $(this);
        var newElement = $("<input type='button' value='Choose File' />");
        newElement.click(function() {
            thisInput$.click();
        });
        thisInput$.after(newElement);
        thisInput$.hide();
    });
});

Here's some sample button CSS that I got from http://cssdeck.com/labs/beautiful-flat-buttons:

input[type=button] {
  position: relative;
  vertical-align: top;
  width: 100%;
  height: 60px;
  padding: 0;
  font-size: 22px;
  color:white;
  text-align: center;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.25);
  background: #454545;
  border: 0;
  border-bottom: 2px solid #2f2e2e;
  cursor: pointer;
  -webkit-box-shadow: inset 0 -2px #2f2e2e;
  box-shadow: inset 0 -2px #2f2e2e;
}
input[type=button]:active {
  top: 1px;
  outline: none;
  -webkit-box-shadow: none;
  box-shadow: none;
}

Can you use if/else conditions in CSS?

Not in the traditional sense, but you can use classes for this, if you have access to the HTML. Consider this:

<p class="normal">Text</p>

<p class="active">Text</p>

and in your CSS file:

p.normal {
  background-position : 150px 8px;
}
p.active {
  background-position : 4px 8px;
}

That's the CSS way to do it.

Then there are CSS preprocessors like Sass. You can use conditionals there, which'd look like this:

$type: monster;
p {
  @if $type == ocean {
    color: blue;
  } @else if $type == matador {
    color: red;
  } @else if $type == monster {
    color: green;
  } @else {
    color: black;
  }
}

Disadvantages are, that you're bound to pre-process your stylesheets, and that the condition is evaluated at compile time, not run time.

A newer feature of CSS proper are custom properties (a.k.a. CSS variables). They are evaluated at run time (in browsers supporting them).

With them you could do something along the line:

:root {
  --main-bg-color: brown;
}

.one {
  background-color: var(--main-bg-color);
}

.two {
  background-color: black;
}

Finally, you can preprocess your stylesheet with your favourite server-side language. If you're using PHP, serve a style.css.php file, that looks something like this:

p {
  background-position: <?php echo (@$_GET['foo'] == 'bar')? "150" : "4"; ?>px 8px;
}

In this case, you will however have a performance impact, since caching such a stylesheet will be difficult.

Assigning a variable NaN in python without numpy

Use float("nan"):

>>> float("nan")
nan

How to style a div to have a background color for the entire width of the content, and not just for the width of the display?

.success { background-color: #cffccc; overflow: scroll; min-width: 100%; }

You can try scroll or auto.

- java.lang.NullPointerException - setText on null object reference

The problem is the tv.setText(text). The variable tv is probably null and you call the setText method on that null, which you can't. My guess that the problem is on the findViewById method, but it's not here, so I can't tell more, without the code.

How to unload a package without restarting R

You can try all you want to remove a package (and all the dependencies it brought in alongside) using unloadNamespace() but the memory footprint will still persist. And no, detach("package:,packageName", unload=TRUE, force = TRUE) will not work either.

From a fresh new console or Session > Restart R check memory with the pryr package:

pryr::mem_used()

# 40.6 MB   ## This will depend on which packages are loaded obviously (can also fluctuate a bit after the decimal)

Check my sessionInfo()

R version 3.6.1 (2019-07-05)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 17763)

Matrix products: default

locale:
[1] LC_COLLATE=English_Canada.1252  LC_CTYPE=English_Canada.1252    LC_MONETARY=English_Canada.1252 LC_NUMERIC=C                   
[5] LC_TIME=English_Canada.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
[1] compiler_3.6.1   pryr_0.1.4       magrittr_1.5     tools_3.6.1      Rcpp_1.0.3       stringi_1.4.3    codetools_0.2-16 stringr_1.4.0   
[9] packrat_0.5.0

Let's load the Seurat package and check the new memory footprint:

library(Seurat)
pryr::mem_used()

# 172 MB    ## Likely to change in the future but just to give you an idea

Let's use unloadNamespace() to remove everything:

unloadNamespace("Seurat")
unloadNamespace("ape")
unloadNamespace("cluster")
unloadNamespace("cowplot")
unloadNamespace("ROCR")
unloadNamespace("gplots")
unloadNamespace("caTools")
unloadNamespace("bitops")
unloadNamespace("fitdistrplus")
unloadNamespace("RColorBrewer")
unloadNamespace("sctransform")
unloadNamespace("future.apply")
unloadNamespace("future")
unloadNamespace("plotly")
unloadNamespace("ggrepel")
unloadNamespace("ggridges")
unloadNamespace("ggplot2")
unloadNamespace("gridExtra")
unloadNamespace("gtable")
unloadNamespace("uwot")
unloadNamespace("irlba")
unloadNamespace("leiden")
unloadNamespace("reticulate")
unloadNamespace("rsvd")
unloadNamespace("survival")
unloadNamespace("Matrix")
unloadNamespace("nlme")
unloadNamespace("lmtest")
unloadNamespace("zoo")
unloadNamespace("metap")
unloadNamespace("lattice")
unloadNamespace("grid")
unloadNamespace("httr")
unloadNamespace("ica")
unloadNamespace("igraph")
unloadNamespace("irlba")
unloadNamespace("KernSmooth")
unloadNamespace("leiden")
unloadNamespace("MASS")
unloadNamespace("pbapply")
unloadNamespace("plotly")
unloadNamespace("png")
unloadNamespace("RANN")
unloadNamespace("RcppAnnoy")
unloadNamespace("tidyr")
unloadNamespace("dplyr")
unloadNamespace("tibble")
unloadNamespace("RANN")
unloadNamespace("tidyselect")
unloadNamespace("purrr")
unloadNamespace("htmlwidgets")
unloadNamespace("htmltools")
unloadNamespace("lifecycle")
unloadNamespace("pillar")
unloadNamespace("vctrs")
unloadNamespace("rlang")
unloadNamespace("Rtsne")
unloadNamespace("SDMTools")
unloadNamespace("Rdpack")
unloadNamespace("bibtex")
unloadNamespace("tsne")
unloadNamespace("backports")
unloadNamespace("R6")
unloadNamespace("lazyeval")
unloadNamespace("scales")
unloadNamespace("munsell")
unloadNamespace("colorspace")
unloadNamespace("npsurv")
unloadNamespace("compiler")
unloadNamespace("digest")
unloadNamespace("R.utils")
unloadNamespace("pkgconfig")
unloadNamespace("gbRd")
unloadNamespace("parallel")
unloadNamespace("gdata")
unloadNamespace("listenv")
unloadNamespace("crayon")
unloadNamespace("splines")
unloadNamespace("zeallot")
unloadNamespace("reshape")
unloadNamespace("glue")
unloadNamespace("lsei")
unloadNamespace("RcppParallel")
unloadNamespace("data.table")
unloadNamespace("viridisLite")
unloadNamespace("globals")

Now check sessionInfo():

R version 3.6.1 (2019-07-05)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 17763)

Matrix products: default

locale:
[1] LC_COLLATE=English_Canada.1252  LC_CTYPE=English_Canada.1252    LC_MONETARY=English_Canada.1252 LC_NUMERIC=C                   
[5] LC_TIME=English_Canada.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

loaded via a namespace (and not attached):
 [1] tools_3.6.1       stringr_1.4.0     rstudioapi_0.10   pryr_0.1.4        jsonlite_1.6      gtools_3.8.1      R.oo_1.22.0      
 [8] magrittr_1.5      Rcpp_1.0.3        R.methodsS3_1.7.1 stringi_1.4.3     plyr_1.8.4        reshape2_1.4.3    codetools_0.2-16 
[15] packrat_0.5.0     assertthat_0.2.1

Check the memory footprint:

pryr::mem_used()

# 173 MB

Link to screen-cast demonstration

Gson: Directly convert String to JsonObject (no POJO)

//import com.google.gson.JsonObject;  
JsonObject complaint = new JsonObject();
complaint.addProperty("key", "value");

In-place edits with sed on OS X

sed -i -- "s/https/http/g" file.txt

Slick.js: Get current and total slides (ie. 3/5)

I had an issue with multiple slides. version 1.8.1

if slidesToShow and slidesToScroll more than 1

trick is in slick.slickGetOption('slidesToShow');

$(".your-selector").on('init reInit afterChange', function(event, slick, currentSlide, nextSlide){
    var i = (currentSlide ? currentSlide : 0) + 1;
    var slidesToShow = slick.slickGetOption('slidesToShow');
    var curPage = parseInt((i-1)/slidesToShow) + 1;
    var lastPage =  parseInt((slick.slideCount-1)/slidesToShow) + 1;
    $('.your-selector').text(curPage);
    $('.your-selector').text(lastPage);
});

Note curPage and lastPage is separate. I had to color them differently.

Based on top-voted answer

Getting one value from a tuple

General

Single elements of a tuple a can be accessed -in an indexed array-like fashion-

via a[0], a[1], ... depending on the number of elements in the tuple.

Example

If your tuple is a=(3,"a")

a[0] yields 3,
a[1] yields "a"

Concrete answer to question

def tup():
  return (3, "hello")

tup() returns a 2-tuple.

In order to "solve"

i = 5 + tup()  # I want to add just the three

you select the 3 by

tup()[0|    #first element

so in total

i = 5 + tup()[0]

Alternatives

Go with namedtuple that allows you to access tuple elements by name (and by index). Details at https://docs.python.org/3/library/collections.html#collections.namedtuple

>>> import collections
>>> MyTuple=collections.namedtuple("MyTuple", "mynumber, mystring")
>>> m = MyTuple(3, "hello")
>>> m[0]
3
>>> m.mynumber
3
>>> m[1]
'hello'
>>> m.mystring
'hello'

Does Java have an exponential operator?

To do this with user input:

public static void getPow(){
    Scanner sc = new Scanner(System.in);
    System.out.println("Enter first integer: ");    // 3
    int first = sc.nextInt();
    System.out.println("Enter second integer: ");    // 2
    int second = sc.nextInt();
    System.out.println(first + " to the power of " + second + " is " + 
        (int) Math.pow(first, second));    // outputs 9

Select multiple columns from a table, but group by one

You can try this:

Select ProductID,ProductName,Sum(OrderQuantity) 
 from OrderDetails Group By ProductID, ProductName

You're only required to Group By columns that doesn't come with an aggregate function in the Select clause. So you can just use Group By ProductID and ProductName in this case.

What does `unsigned` in MySQL mean and when to use it?

MySQL says:

All integer types can have an optional (nonstandard) attribute UNSIGNED. Unsigned type can be used to permit only nonnegative numbers in a column or when you need a larger upper numeric range for the column. For example, if an INT column is UNSIGNED, the size of the column's range is the same but its endpoints shift from -2147483648 and 2147483647 up to 0 and 4294967295.

When do I use it ?

Ask yourself this question: Will this field ever contain a negative value?
If the answer is no, then you want an UNSIGNED data type.

A common mistake is to use a primary key that is an auto-increment INT starting at zero, yet the type is SIGNED, in that case you’ll never touch any of the negative numbers and you are reducing the range of possible id's to half.

How to change default format at created_at and updated_at value laravel

Laravel 4.x and 5.0

To change the time in the database use: http://laravel.com/docs/4.2/eloquent#timestamps

Providing A Custom Timestamp Format

If you wish to customize the format of your timestamps, you may override the getDateFormat method in your model:

class User extends Eloquent {

    protected function getDateFormat()
    {
        return 'U';
    }

}

Laravel 5.1+

https://laravel.com/docs/5.1/eloquent

If you need to customize the format of your timestamps, set the $dateFormat property on your model. This property determines how date attributes are stored in the database, as well as their format when the model is serialized to an array or JSON:

class Flight extends Model
{
    /**
     * The storage format of the model's date columns.
     *
     * @var string
     */
    protected $dateFormat = 'U';
}

How do I activate a specific workbook and a specific sheet?

try this

Windows("name.xls").Activate

How to convert an NSString into an NSNumber

extension String {

    var numberValue:NSNumber? {
        let formatter = NumberFormatter()
        formatter.numberStyle = .decimal
        return formatter.number(from: self)
    }
}

let someFloat = "12.34".numberValue

jQuery find element by data attribute value

I searched for a the same solution with a variable instead of the String.
I hope i can help someone with my solution :)

var numb = "3";
$(`#myid[data-tab-id=${numb}]`);

Is there a way since (iOS 7's release) to get the UDID without using iTunes on a PC/Mac?

Please use test flight to obtain UDID from testers but not using untrusted source e.g. http://get.udid.io/

You can 1. Invite testers in email from test flight webpage. Testers open the link in email and install a profile from test flight. Therefore developers can obtain UDIDs on the test flight webpage. 2. Add those UDIDs on the Apple provisioning portal.

(Ref: http://help.testflightapp.com/customer/portal/articles/829537-how-does-it-work-)

The process doesn't require testers to use Mac/ PC to obtain UDID (more convenient). And I think test flight is a company that can be trusted (no worries when passing UDID to this company).

I have tested this method and it works on iOS 8.

How can I create an array/list of dictionaries in python?

Minor variation to user1850980's answer (for the question "How to initialize a list of empty dictionaries") using list constructor:

dictlistGOOD = list( {} for i in xrange(listsize) )

I found out to my chagrin, this does NOT work:

dictlistFAIL = [{}] * listsize  # FAIL!

as it creates a list of references to the same empty dictionary, so that if you update one dictionary in the list, all the other references get updated too.

Try these updates to see the difference:

dictlistGOOD[0]["key"] = "value"
dictlistFAIL[0]["key"] = "value"

(I was actually looking for user1850980's answer to the question asked, so his/her answer was helpful.)

Maven compile: package does not exist

Not sure if there was file corruption or what, but after confirming proper pom configuration I was able to resolve this issue by deleting the jar from my local m2 repository, forcing Maven to download it again when I ran the tests.

How to check for an empty struct?

Just a quick addition, because I tackled the same issue today:

With Go 1.13 it is possible to use the new isZero() method:

if reflect.ValueOf(session).IsZero() {
     // do stuff...
}

I didn't test this regarding performance, but I guess that this should be faster, than comparing via reflect.DeepEqual().

Typescript: difference between String and string

TypeScript: `String` vs `string`

Argument of type 'String' is not assignable to parameter of type 'string'.

'string' is a primitive, but 'String' is a wrapper object.

Prefer using 'string' when possible.

demo

String Object

// error
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: String = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: String = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

string primitive

// ok
class SVGStorageUtils {
  store: object;
  constructor(store: object) {
    this.store = store;
  }
  setData(key: string = ``, data: object) {
    sessionStorage.setItem(key, JSON.stringify(data));
  }
  getData(key: string = ``) {
    const obj = JSON.parse(sessionStorage.getItem(key));
  }
}

Validate form field only on submit or user input

If you want to show error messages on form submission, you can use condition form.$submitted to check if an attempt was made to submit the form. Check following example.

<form name="myForm" novalidate ng-submit="myForm.$valid && createUser()">
  <input type="text" name="name" ng-model="user.name" placeholder="Enter name of user" required>
  <div ng-messages="myForm.name.$error" ng-if="myForm.$submitted">
    <div ng-message="required">Please enter user name.</div>
  </div>

  <input type="text" name="address" ng-model="user.address" placeholder="Enter Address" required ng-maxlength="30">
  <div ng-messages="myForm.name.$error" ng-if="myForm.$submitted">
    <div ng-message="required">Please enter user address.</div>
    <div ng-message="maxlength">Should be less than 30 chars</div>
  </div>

  <button type="submit">
    Create user
  </button>
</form>

Convert Mat to Array/Vector in OpenCV

You can use iterators:

Mat matrix = ...;

std::vector<float> vec(matrix.begin<float>(), matrix.end<float>());

Changing ImageView source

If you want to set in imageview an image that is inside the mipmap dirs you can do it like this:

myImageView.setImageDrawable(getResources().getDrawable(R.mipmap.my_picture)

Query Mongodb on month, day, year... of a datetime

You can use MongoDB_DataObject wrapper to perform such query like below:

$model = new MongoDB_DataObject('orders');

$model->whereAdd('MONTH(created) = 4 AND YEAR(created) = 2016');

$model->find();

while ($model->fetch()) {
    var_dump($model);
}

OR, similarly, using direct query string:

$model = new MongoDB_DataObject();

$model->query('SELECT * FROM orders WHERE MONTH(created) = 4 AND YEAR(created) = 2016');

while ($model->fetch()) {
    var_dump($model);
}

Passing just a type as a parameter in C#

You can do this, just wrap it in typeof()

foo.GetColumnValues(typeof(int))

public void GetColumnValues(Type type)
{
    //logic
}

delete map[key] in go?

Copied from Go 1 release notes

In the old language, to delete the entry with key k from the map represented by m, one wrote the statement,

m[k] = value, false

This syntax was a peculiar special case, the only two-to-one assignment. It required passing a value (usually ignored) that is evaluated but discarded, plus a boolean that was nearly always the constant false. It did the job but was odd and a point of contention.

In Go 1, that syntax has gone; instead there is a new built-in function, delete. The call

delete(m, k)

will delete the map entry retrieved by the expression m[k]. There is no return value. Deleting a non-existent entry is a no-op.

Updating: Running go fix will convert expressions of the form m[k] = value, false into delete(m, k) when it is clear that the ignored value can be safely discarded from the program and false refers to the predefined boolean constant. The fix tool will flag other uses of the syntax for inspection by the programmer.

How to disable javax.swing.JButton in java?

The code is very long so I can't paste all the code.

There could be any number of reasons why your code doesn't work. Maybe you declared the button variables twice so you aren't actually changing enabling/disabling the button like you think you are. Maybe you are blocking the EDT.

You need to create a SSCCE to post on the forum.

So its up to you to isolate the problem. Start with a simple frame thas two buttons and see if your code works. Once you get that working, then try starting a Thread that simply sleeps for 10 seconds to see if it still works.

Learn how the basice work first before writing a 200 line program.

Learn how to do some basic debugging, we are not mind readers. We can't guess what silly mistake you are doing based on your verbal description of the problem.

SQL: Alias Column Name for Use in CASE Statement

SELECT
    a AS [blabla a],
    b [blabla b],
    CASE c
        WHEN 1 THEN 'aaa'
        WHEN 2 THEN 'bbb'
        ELSE 'unknown' 
    END AS [my alias], 
    d AS [blabla d]
FROM mytable

Where does application data file actually stored on android device?

You can get if from your document_cache folder, subfolder (mine is 1946507). Once there, rename the "content" by adding .pdf to the end of the file, save, and open with any pdf reader.

What is the difference between an int and a long in C++?

It depends on your compiler. You are guaranteed that a long will be at least as large as an int, but you are not guaranteed that it will be any longer.

Oracle SQL Developer and PostgreSQL

If there is no database with the same name as the username, then clicking "Choose Database" will fail with an error like "Status : Failure -FATAL: database "your_username" does not exist"

To work around this, put 5432/database_name? in the Port field, where 5432 is the port of your Postgres instance and database_name is the name of at an existing database that your_username has access to. Then click "Choose Database" again and it should work. Now you can choose the database you want and remove the extra /database_name? from the Port field.

How to add Headers on RESTful call using Jersey Client API

I use the header(name, value) method and give the return to webResource var:

Client client = Client.create();
WebResource webResource = client.resource("uri");

MultivaluedMap<String, String> queryParams = new MultivaluedMapImpl();
queryParams.add("json", js); //set parametes for request

appKey = "Bearer " + appKey; // appKey is unique number

//Get response from RESTful Server get(ClientResponse.class);
ClientResponse response = webResource.queryParams(queryParams)
    .header("Content-Type", "application/json;charset=UTF-8")
    .header("Authorization", appKey)
    .get(ClientResponse.class);

String jsonStr = response.getEntity(String.class);

Laravel - Eloquent or Fluent random row

For Laravel 5.2 >=

use the Eloquent method:

inRandomOrder()

The inRandomOrder method may be used to sort the query results randomly. For example, you may use this method to fetch a random user:

$randomUser = DB::table('users')
            ->inRandomOrder()
            ->first();

from docs: https://laravel.com/docs/5.2/queries#ordering-grouping-limit-and-offset

How to restart a windows service using Task Scheduler

Instead of using a bat file, you can simply create a Scheduled Task. Most of the time you define just one action. In this case, create two actions with the NET command. The first one to stop the service, the second one to start the service. Give them a STOP and START argument, followed by the service name.

In this example we restart the Printer Spooler service.

NET STOP "Print Spooler" 
NET START "Print Spooler"

Note: unfortunately NET RESTART <service name> does not exist.

ASP.NET MVC3 Razor - Html.ActionLink style

Reviving an old question because it seems to appear at the top of search results.

I wanted to retain transition effects while still being able to style the actionlink so I came up with this solution.

I wrapped the action link with a div that would contain the parent style:

<div class="parent-style-one">
      @Html.ActionLink("Homepage", "Home", "Home")
</div>

Next I create the CSS for the div, this will be the parent css and will be inherited by the child elements such as the action link.

  .parent-style-one {
     /* your styles here */
  }

Because all an action link is, is an element when broken down as html so you just need to target that element in your css selection:

  .parent-style-one a {
     text-decoration: none;
  }

For transition effects I did this:

  .parent-style-one a:hover {
        text-decoration: underline;
        -webkit-transition-duration: 1.1s; /* Safari */
        transition-duration: 1.1s;         
  }

This way I only target the child elements of the div in this case the action link and still be able to apply transition effects.

How do I find out which settings.xml file maven is using

Use the Maven debug option, ie mvn -X :

Apache Maven 3.0.3 (r1075438; 2011-02-28 18:31:09+0100)
Maven home: /usr/java/apache-maven-3.0.3
Java version: 1.6.0_12, vendor: Sun Microsystems Inc.
Java home: /usr/java/jdk1.6.0_12/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "2.6.32-32-generic", arch: "i386", family: "unix"
[INFO] Error stacktraces are turned on.
[DEBUG] Reading global settings from /usr/java/apache-maven-3.0.3/conf/settings.xml
[DEBUG] Reading user settings from /home/myhome/.m2/settings.xml
...

In this output, you can see that the settings.xml is loaded from /home/myhome/.m2/settings.xml.

How to "properly" print a list?

Using only print:

>>> l = ['x', 3, 'b']
>>> print(*l, sep='\n')
x
3
b
>>> print(*l, sep=', ')
x, 3, b

Throw HttpResponseException or return Request.CreateErrorResponse?

The approach I have taken is to just throw exceptions from the api controller actions and have an exception filter registered that processes the exception and sets an appropriate response on the action execution context.

The filter exposes a fluent interface that provides a means of registering handlers for specific types of exceptions prior to registering the filter with global configuration.

The use of this filter enables centralized exception handling instead of spreading it across the controller actions. There are however cases where I will catch exceptions within the controller action and return a specific response if it does not make sense to centralize the handling of that particular exception.

Example registration of filter:

GlobalConfiguration.Configuration.Filters.Add(
    new UnhandledExceptionFilterAttribute()
    .Register<KeyNotFoundException>(HttpStatusCode.NotFound)

    .Register<SecurityException>(HttpStatusCode.Forbidden)

    .Register<SqlException>(
        (exception, request) =>
        {
            var sqlException = exception as SqlException;

            if (sqlException.Number > 50000)
            {
                var response            = request.CreateResponse(HttpStatusCode.BadRequest);
                response.ReasonPhrase   = sqlException.Message.Replace(Environment.NewLine, String.Empty);

                return response;
            }
            else
            {
                return request.CreateResponse(HttpStatusCode.InternalServerError);
            }
        }
    )
);

UnhandledExceptionFilterAttribute class:

using System;
using System.Collections.Concurrent;
using System.Net;
using System.Net.Http;
using System.Text;
using System.Web.Http.Filters;

namespace Sample
{
    /// <summary>
    /// Represents the an attribute that provides a filter for unhandled exceptions.
    /// </summary>
    public class UnhandledExceptionFilterAttribute : ExceptionFilterAttribute
    {
        #region UnhandledExceptionFilterAttribute()
        /// <summary>
        /// Initializes a new instance of the <see cref="UnhandledExceptionFilterAttribute"/> class.
        /// </summary>
        public UnhandledExceptionFilterAttribute() : base()
        {

        }
        #endregion

        #region DefaultHandler
        /// <summary>
        /// Gets a delegate method that returns an <see cref="HttpResponseMessage"/> 
        /// that describes the supplied exception.
        /// </summary>
        /// <value>
        /// A <see cref="Func{Exception, HttpRequestMessage, HttpResponseMessage}"/> delegate method that returns 
        /// an <see cref="HttpResponseMessage"/> that describes the supplied exception.
        /// </value>
        private static Func<Exception, HttpRequestMessage, HttpResponseMessage> DefaultHandler = (exception, request) =>
        {
            if(exception == null)
            {
                return null;
            }

            var response            = request.CreateResponse<string>(
                HttpStatusCode.InternalServerError, GetContentOf(exception)
            );
            response.ReasonPhrase   = exception.Message.Replace(Environment.NewLine, String.Empty);

            return response;
        };
        #endregion

        #region GetContentOf
        /// <summary>
        /// Gets a delegate method that extracts information from the specified exception.
        /// </summary>
        /// <value>
        /// A <see cref="Func{Exception, String}"/> delegate method that extracts information 
        /// from the specified exception.
        /// </value>
        private static Func<Exception, string> GetContentOf = (exception) =>
        {
            if (exception == null)
            {
                return String.Empty;
            }

            var result  = new StringBuilder();

            result.AppendLine(exception.Message);
            result.AppendLine();

            Exception innerException = exception.InnerException;
            while (innerException != null)
            {
                result.AppendLine(innerException.Message);
                result.AppendLine();
                innerException = innerException.InnerException;
            }

            #if DEBUG
            result.AppendLine(exception.StackTrace);
            #endif

            return result.ToString();
        };
        #endregion

        #region Handlers
        /// <summary>
        /// Gets the exception handlers registered with this filter.
        /// </summary>
        /// <value>
        /// A <see cref="ConcurrentDictionary{Type, Tuple}"/> collection that contains 
        /// the exception handlers registered with this filter.
        /// </value>
        protected ConcurrentDictionary<Type, Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>>> Handlers
        {
            get
            {
                return _filterHandlers;
            }
        }
        private readonly ConcurrentDictionary<Type, Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>>> _filterHandlers = new ConcurrentDictionary<Type, Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>>>();
        #endregion

        #region OnException(HttpActionExecutedContext actionExecutedContext)
        /// <summary>
        /// Raises the exception event.
        /// </summary>
        /// <param name="actionExecutedContext">The context for the action.</param>
        public override void OnException(HttpActionExecutedContext actionExecutedContext)
        {
            if(actionExecutedContext == null || actionExecutedContext.Exception == null)
            {
                return;
            }

            var type    = actionExecutedContext.Exception.GetType();

            Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>> registration = null;

            if (this.Handlers.TryGetValue(type, out registration))
            {
                var statusCode  = registration.Item1;
                var handler     = registration.Item2;

                var response    = handler(
                    actionExecutedContext.Exception.GetBaseException(), 
                    actionExecutedContext.Request
                );

                // Use registered status code if available
                if (statusCode.HasValue)
                {
                    response.StatusCode = statusCode.Value;
                }

                actionExecutedContext.Response  = response;
            }
            else
            {
                // If no exception handler registered for the exception type, fallback to default handler
                actionExecutedContext.Response  = DefaultHandler(
                    actionExecutedContext.Exception.GetBaseException(), actionExecutedContext.Request
                );
            }
        }
        #endregion

        #region Register<TException>(HttpStatusCode statusCode)
        /// <summary>
        /// Registers an exception handler that returns the specified status code for exceptions of type <typeparamref name="TException"/>.
        /// </summary>
        /// <typeparam name="TException">The type of exception to register a handler for.</typeparam>
        /// <param name="statusCode">The HTTP status code to return for exceptions of type <typeparamref name="TException"/>.</param>
        /// <returns>
        /// This <see cref="UnhandledExceptionFilterAttribute"/> after the exception handler has been added.
        /// </returns>
        public UnhandledExceptionFilterAttribute Register<TException>(HttpStatusCode statusCode) 
            where TException : Exception
        {

            var type    = typeof(TException);
            var item    = new Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>>(
                statusCode, DefaultHandler
            );

            if (!this.Handlers.TryAdd(type, item))
            {
                Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>> oldItem = null;

                if (this.Handlers.TryRemove(type, out oldItem))
                {
                    this.Handlers.TryAdd(type, item);
                }
            }

            return this;
        }
        #endregion

        #region Register<TException>(Func<Exception, HttpRequestMessage, HttpResponseMessage> handler)
        /// <summary>
        /// Registers the specified exception <paramref name="handler"/> for exceptions of type <typeparamref name="TException"/>.
        /// </summary>
        /// <typeparam name="TException">The type of exception to register the <paramref name="handler"/> for.</typeparam>
        /// <param name="handler">The exception handler responsible for exceptions of type <typeparamref name="TException"/>.</param>
        /// <returns>
        /// This <see cref="UnhandledExceptionFilterAttribute"/> after the exception <paramref name="handler"/> 
        /// has been added.
        /// </returns>
        /// <exception cref="ArgumentNullException">The <paramref name="handler"/> is <see langword="null"/>.</exception>
        public UnhandledExceptionFilterAttribute Register<TException>(Func<Exception, HttpRequestMessage, HttpResponseMessage> handler) 
            where TException : Exception
        {
            if(handler == null)
            {
              throw new ArgumentNullException("handler");
            }

            var type    = typeof(TException);
            var item    = new Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>>(
                null, handler
            );

            if (!this.Handlers.TryAdd(type, item))
            {
                Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>> oldItem = null;

                if (this.Handlers.TryRemove(type, out oldItem))
                {
                    this.Handlers.TryAdd(type, item);
                }
            }

            return this;
        }
        #endregion

        #region Unregister<TException>()
        /// <summary>
        /// Unregisters the exception handler for exceptions of type <typeparamref name="TException"/>.
        /// </summary>
        /// <typeparam name="TException">The type of exception to unregister handlers for.</typeparam>
        /// <returns>
        /// This <see cref="UnhandledExceptionFilterAttribute"/> after the exception handler 
        /// for exceptions of type <typeparamref name="TException"/> has been removed.
        /// </returns>
        public UnhandledExceptionFilterAttribute Unregister<TException>()
            where TException : Exception
        {
            Tuple<HttpStatusCode?, Func<Exception, HttpRequestMessage, HttpResponseMessage>> item = null;

            this.Handlers.TryRemove(typeof(TException), out item);

            return this;
        }
        #endregion
    }
}

Source code can also be found here.

FragmentActivity to Fragment

first of all;

a Fragment must be inside a FragmentActivity, that's the first rule,

a FragmentActivity is quite similar to a standart Activity that you already know, besides having some Fragment oriented methods

second thing about Fragments, is that there is one important method you MUST call, wich is onCreateView, where you inflate your layout, think of it as the setContentLayout

here is an example:

    @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {     mView       = inflater.inflate(R.layout.fragment_layout, container, false);       return mView; }

and continu your work based on that mView, so to find a View by id, call mView.findViewById(..);

for the FragmentActivity part:

the xml part "must" have a FrameLayout in order to inflate a fragment in it

        <FrameLayout             android:id="@+id/content_frame"             android:layout_width="match_parent"             android:layout_height="match_parent"  >         </FrameLayout>

as for the inflation part

getSupportFragmentManager().beginTransaction().replace(R.id.content_frame, new YOUR_FRAGMENT, "TAG").commit();

begin with these, as there is tons of other stuf you must know about fragments and fragment activities, start of by reading something about it (like life cycle) at the android developer site

How do I use tools:overrideLibrary in a build.gradle file?

it doesn't matter that you declare your minSdk in build.gradle. You have to copy overrideLibrary in your AndroidManifest.xml, as documented here.

<manifest 
    ... >
<uses-sdk tools:overrideLibrary="com.example.lib1, com.example.lib2"/>
    ...
</manifest>

The system automatically ignores the sdkVersion declared in AndroidManifest.xml.

I hope this solve your problem.

How do I store and retrieve a blob from sqlite?

You need to use sqlite's prepared statements interface. Basically, the idea is that you prepare a statement with a placeholder for your blob, then use one of the bind calls to "bind" your data...

SQLite Prepared Statements

What does the "__block" keyword mean?

@bbum covers blocks in depth in a blog post and touches on the __block storage type.

__block is a distinct storage type

Just like static, auto, and volatile, __block is a storage type. It tells the compiler that the variable’s storage is to be managed differently.

...

However, for __block variables, the block does not retain. It is up to you to retain and release, as needed.
...

As for use cases you will find __block is sometimes used to avoid retain cycles since it does not retain the argument. A common example is using self.

//Now using myself inside a block will not 
//retain the value therefore breaking a
//possible retain cycle.
__block id myself = self;

Deck of cards JAVA

public class shuffleCards{

    public static void main(String[] args) {

        String[] cardsType ={"club","spade","heart","diamond"};
        String [] cardValue = {"Ace","2","3","4","5","6","7","8","9","10","King", "Queen", "Jack" };

        List<String> cards = new ArrayList<String>();
        for(int i=0;i<=(cardsType.length)-1;i++){
            for(int j=0;j<=(cardValue.length)-1;j++){
                cards.add(cardsType[i] + " " + "of" + " " + cardValue[j]) ;
            }
        }

        Collections.shuffle(cards);
        System.out.print("Enter the number of cards within:" + cards.size() + " = ");

        Scanner data = new Scanner(System.in);
        Integer inputString = data.nextInt();
        for(int l=0;l<= inputString -1;l++){
            System.out.print( cards.get(l)) ;
        }    
    }
}

Android Studio: /dev/kvm device permission denied

Step 1: (Install qemu-kvm)

sudo apt install qemu-kvm

Step 2: (Add your user to kvm group using)

sudo adduser username kvm

Step 3: (If still showing permission denied)

sudo chown username /dev/kvm

Final step:

ls -al /dev/kvm

Why does an onclick property set with setAttribute fail to work in IE?

There is a LARGE collection of attributes you can't set in IE using .setAttribute() which includes every inline event handler.

See here for details:

http://webbugtrack.blogspot.com/2007/08/bug-242-setattribute-doesnt-always-work.html

How to return a specific element of an array?

You code should look like this:

public int getElement(int[] arrayOfInts, int index) {
    return arrayOfInts[index];
}

Main points here are method return type, it should match with array elements type and if you are working from main() - this method must be static also.

How to multiply all integers inside list

using numpy :

    In [1]: import numpy as np

    In [2]: nums = np.array([1,2,3])*2

    In [3]: nums.tolist()
    Out[4]: [2, 4, 6]

Why check both isset() and !empty()

$a = 0;
if (isset($a)) { //$a is set because it has some value ,eg:0
    echo '$a has value';
}
if (!empty($a)) { //$a is empty because it has value 0
    echo '$a is not empty';
} else {
    echo '$a is empty';
}

How do I set the default schema for a user in MySQL

There is no default database for user. There is default database for current session.

You can get it using DATABASE() function -

SELECT DATABASE();

And you can set it using USE statement -

USE database1;

You should set it manually - USE db_name, or in the connection string.

CMake does not find Visual C++ compiler

Those stumbling with this on Visual Studio 2017: there is a feature related to CMake that needs to be selected and installed together with the relevant compiler toolsets. See the screenshot below.

Scroll event listener javascript

Wont the below basic approach doesn't suffice your requirements?

HTML Code having a div

<div id="mydiv" onscroll='myMethod();'>

JS will have below code

function myMethod(){ alert(1); }

How to resolve "local edit, incoming delete upon update" message

Short version:

$ svn st
!  +  C foo
      >   local edit, incoming delete upon update
!  +  C bar
      >   local edit, incoming delete upon update
$ touch foo bar
$ svn revert foo bar
$ rm foo bar

If the conflict is about directories instead of files then replace touch with mkdir and rm with rm -r.

Note: the same procedure also work for the following situation:

$ svn st
!     C foo
      >   local delete, incoming delete upon update
!     C bar
      >   local delete, incoming delete upon update

Long version:

This happens when you edit a file while someone else deleted the file and commited first. As a good svn citizen you do an update before a commit. Now you have a conflict. Realising that deleting the file is the right thing to do you delete the file from your working copy. Instead of being content svn now complains that the local files are missing and that there is a conflicting update which ultimately wants to see the files deleted. Good job svn.

Should svn resolve not work, for whatever reason, you can do the following:

Initial situation: Local files are missing, update is conflicting.

$ svn st
!  +  C foo
      >   local edit, incoming delete upon update
!  +  C bar
      >   local edit, incoming delete upon update

Recreate the conflicting files:

$ touch foo bar

If the conflict is about directories then replace touch with mkdir.

New situation: Local files to be added to the repository (yeah right, svn, whatever you say), update still conflicting.

$ svn st
A  +  C foo
      >   local edit, incoming delete upon update
A  +  C bar
      >   local edit, incoming delete upon update

Revert the files to the state svn likes them (that means deleted):

$ svn revert foo bar

New situation: Local files not known to svn, update no longer conflicting.

$ svn st
?       foo
?       bar

Now we can delete the files:

$ rm foo bar

If the conflict is about directories then replace rm with rm -r.

svn no longer complains:

$ svn st

Done.

How to count lines of Java code using IntelliJ IDEA?

Quick and dirty way is to do a global search for '\n'. You can filter it any way you like on file extensions etc.

Ctrl-Shift-F -> Text to find = '\n' -> Find.

Edit: And 'regular expression' has to be checked.

Is it more efficient to copy a vector by reserving and copying, or by creating and swapping?

Your second example does not work if you send the argument by reference. Did you mean

void copyVecFast(vec<int> original) // no reference
{

  vector<int> new_;
  new_.swap(original); 
}

That would work, but an easier way is

vector<int> new_(original);

How to make the webpack dev server run on port 80 and on 0.0.0.0 to make it publicly accessible?

If you're in a React Application created with 'create-react-app' go to your package.json and change

"start": "react-scripts start",

to ... (unix)

"start": "PORT=80 react-scripts start",

or to ... (win)

"start": "set PORT=3005 && react-scripts start"

PHP check whether property exists in object or class

Using array_key_exists() on objects is Deprecated in php 7.4

Instead either isset() or property_exists() should be used

reference : php.net

Plot bar graph from Pandas DataFrame

To plot just a selection of your columns you can select the columns of interest by passing a list to the subscript operator:

ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)

What you tried was df['V1','V2'] this will raise a KeyError as correctly no column exists with that label, although it looks funny at first you have to consider that your are passing a list hence the double square brackets [[]].

import matplotlib.pyplot as plt
ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)
ax.set_xlabel("Hour", fontsize=12)
ax.set_ylabel("V", fontsize=12)
plt.show()

enter image description here

String comparison: InvariantCultureIgnoreCase vs OrdinalIgnoreCase?

Neither code is always better. They do different things, so they are good at different things.

InvariantCultureIgnoreCase uses comparison rules based on english, but without any regional variations. This is good for a neutral comparison that still takes into account some linguistic aspects.

OrdinalIgnoreCase compares the character codes without cultural aspects. This is good for exact comparisons, like login names, but not for sorting strings with unusual characters like é or ö. This is also faster because there are no extra rules to apply before comparing.

How to pass arguments to addEventListener listener function?

You can just bind all necessary arguments with 'bind':

root.addEventListener('click', myPrettyHandler.bind(null, event, arg1, ... ));

In this way you'll always get the event, arg1, and other stuff passed to myPrettyHandler.

http://passy.svbtle.com/partial-application-in-javascript-using-bind

Using grep to help subset a data frame in R

It's pretty straightforward using [ to extract:

grep will give you the position in which it matched your search pattern (unless you use value = TRUE).

grep("^G45", My.Data$x)
# [1] 2

Since you're searching within the values of a single column, that actually corresponds to the row index. So, use that with [ (where you would use My.Data[rows, cols] to get specific rows and columns).

My.Data[grep("^G45", My.Data$x), ]
#      x y
# 2 G459 2

The help-page for subset shows how you can use grep and grepl with subset if you prefer using this function over [. Here's an example.

subset(My.Data, grepl("^G45", My.Data$x))
#      x y
# 2 G459 2

As of R 3.3, there's now also the startsWith function, which you can again use with subset (or with any of the other approaches above). According to the help page for the function, it's considerably faster than using substring or grepl.

subset(My.Data, startsWith(as.character(x), "G45"))
#      x y
# 2 G459 2

Responsive css background images

Responsive website by add padding into bottom image height/width x 100 = padding-bottom %:

http://www.outsidethebracket.com/responsive-web-design-fluid-background-images/

More complicated method:

http://voormedia.com/blog/2012/11/responsive-background-images-with-fixed-or-fluid-aspect-ratios

Try to resize background eq Firefox Ctrl + M to see magic nice script i think best one:

http://www.minimit.com/demos/fullscreen-backgrounds-with-centered-content

How do I to insert data into an SQL table using C# as well as implement an upload function?

You should use parameters in your query to prevent attacks, like if someone entered '); drop table ArticlesTBL;--' as one of the values.

string query = "INSERT INTO ArticlesTBL (ArticleTitle, ArticleContent, ArticleType, ArticleImg, ArticleBrief,  ArticleDateTime, ArticleAuthor, ArticlePublished, ArticleHomeDisplay, ArticleViews)";
query += " VALUES (@ArticleTitle, @ArticleContent, @ArticleType, @ArticleImg, @ArticleBrief, @ArticleDateTime, @ArticleAuthor, @ArticlePublished, @ArticleHomeDisplay, @ArticleViews)";

SqlCommand myCommand = new SqlCommand(query, myConnection);
myCommand.Parameters.AddWithValue("@ArticleTitle", ArticleTitleTextBox.Text);
myCommand.Parameters.AddWithValue("@ArticleContent", ArticleContentTextBox.Text);
// ... other parameters
myCommand.ExecuteNonQuery();

Exploits of a Mom

(xkcd)

How to send email from MySQL 5.1

I would be very concerned about putting the load of sending e-mails on my database server (small though it may be). I might suggest one of these alternatives:

Have application logic detect the need to send an e-mail and send it.
Have a MySQL trigger populate a table that queues up the e-mails to be sent and have a process monitor that table and send the e-mails.

Is there a combination of "LIKE" and "IN" in SQL?

I'm working with SQl Server and Oracle here but I'm interested if this is possible in any RDBMS at all.

Teradata supports LIKE ALL/ANY syntax:

ALL every string in the list.
ANY any string in the list.

+-------------------------------------------------------------------+
¦      THIS expression …       ¦ IS equivalent to this expression … ¦
+------------------------------+------------------------------------¦
¦ x LIKE ALL ('A%','%B','%C%') ¦ x LIKE 'A%'                        ¦
¦                              ¦ AND x LIKE '%B'                    ¦
¦                              ¦ AND x LIKE '%C%'                   ¦
¦                              ¦                                    ¦
¦ x LIKE ANY ('A%','%B','%C%') ¦ x LIKE 'A%'                        ¦
¦                              ¦ OR x LIKE '%B'                     ¦
¦                              ¦ OR x LIKE '%C%'                    ¦
+-------------------------------------------------------------------+

EDIT:

jOOQ version 3.12.0 supports that syntax:

Add synthetic [NOT] LIKE ANY and [NOT] LIKE ALL operators

A lot of times, SQL users would like to be able to combine LIKE and IN predicates, as in:
SELECT *
FROM customer
WHERE last_name [ NOT ] LIKE ANY ('A%', 'E%') [ ESCAPE '!' ]
The workaround is to manually expand the predicate to the equivalent
SELECT *
FROM customer
WHERE last_name LIKE 'A%'
OR last_name LIKE 'E%'
jOOQ could support such a synthetic predicate out of the box.

PostgreSQL LIKE/ILIKE ANY (ARRAY[]):

SELECT *
FROM t
WHERE c LIKE ANY (ARRAY['A%', '%B']);

SELECT *
FROM t
WHERE c LIKE ANY ('{"Do%", "%at"}');

db<>fiddle demo

Snowflake also supports LIKE ANY/LIKE ALL matching:

LIKE ANY/ALL

Allows case-sensitive matching of strings based on comparison with one or more patterns.
<subject> LIKE ANY (<pattern1> [, <pattern2> ... ] ) [ ESCAPE <escape_char> ]

Example:

SELECT * 
FROM like_example 
WHERE subject LIKE ANY ('%Jo%oe%','T%e')
-- WHERE subject LIKE ALL ('%Jo%oe%','J%e')

How to add an existing folder with files to SVN?

Let's try.. It is working for me..

svn add * --force

Programs & Examples On #Routedcommand

Error: the entity type requires a primary key

Why is visible="false" not working for a plain html table?

z-index not working with fixed positioning

Solutions

The Real Problem

When a stacking context is formed

Stacking Order within a Stacking Context

What's the difference between all the Selection Segues?

How to send PUT, DELETE HTTP request in HttpURLConnection?

How to assert two list contain the same elements in Python?

Use jquery click to handle anchor onClick()

Regex matching beginning AND end strings

Mongoose.js: Find user by username LIKE value

Ignoring upper case and lower case in Java

WebForms UnobtrusiveValidationMode requires a ScriptResourceMapping for 'jquery'. Please add a ScriptResourceMapping named jquery(case-sensitive)

Base64 encoding and decoding in client-side Javascript

SQL Server - SELECT FROM stored procedure

Returning value from called function in a shell script

multiple where condition codeigniter

Move a view up only when the keyboard covers an input field

What are the alternatives now that the Google web search API has been deprecated?

A Windows equivalent of the Unix tail command

Is it not possible to stringify an Error using JSON.stringify?

Rails: call another controller action from a controller

Python/Django: log to console under runserver, log to file under Apache

How can I read command line parameters from an R script?

Mask for an Input to allow phone numbers?

Razor/CSHTML - Any Benefit over what we have?

How to save select query results within temporary table?

Replacing Numpy elements if condition is met

Can I set max_retries for requests.request?

How can I display a messagebox in ASP.NET?

Convert HTML to NSAttributedString in iOS

How to write file in UTF-8 format?

What does "hard coded" mean?

How to lock orientation of one view controller to portrait mode only in Swift

Specifying maxlength for multiline textbox

AJAX reload page with POST

jquery: get id from class selector

MongoDB Data directory /data/db not found

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

how to use ng-option to set default value of select element

Disable back button in android

What is "overhead"?

Convert array of strings to List<string>

How to merge a specific commit in Git

Which port(s) does XMPP use?

How do you grep a file and get the next 5 lines

SQL Server Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >=

Declaring an HTMLElement Typescript

Keyword not supported: "data source" initializing Entity Framework Context

Uncaught TypeError: Cannot use 'in' operator to search for 'length' in

String replacement in java, similar to a velocity template

scrollIntoView Scrolls just too far

Fix it in 20 seconds:

How to bind inverse boolean properties in WPF?

com.google.android.gms:play-services-measurement-base is being requested by various other libraries

Change Primary Key

Which characters are valid/invalid in a JSON key name?

Can functions be passed as parameters?

How to write a confusion matrix in Python?

Nginx location priority

Python 3 sort a dict by its values

How to send data to COM PORT using JAVA?

open read and close a file in 1 line of code

git status shows modifications, git checkout -- <file> doesn't remove them

What's the best way to generate a UML diagram from Python source code?

What is /dev/null 2>&1?

What is the maximum possible length of a query string?

Line Break in XML formatting?

What is the difference between a .cpp file and a .h file?

How to fast get Hardware-ID in C#?

How to: Create trigger for auto update modified date with SQL Server 2008

What is the iBeacon Bluetooth Profile

Get item in the list in Scala?

Get Android shared preferences value in activity/normal class

Are there any style options for the HTML5 Date picker?

How to uninstall Anaconda completely from macOS

Common MySQL fields and their appropriate data types