Programs & Examples On #Phpundercontrol

phpUnderControl is a PHP centric add-on to the CruiseControl CI server

What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?

When you use VARIABLE = value, if value is actually a reference to another variable, then the value is only determined when VARIABLE is used. This is best illustrated with an example:

VAL = foo
VARIABLE = $(VAL)
VAL = bar

# VARIABLE and VAL will both evaluate to "bar"

When you use VARIABLE := value, you get the value of value as it is now. For example:

VAL = foo
VARIABLE := $(VAL)
VAL = bar

# VAL will evaluate to "bar", but VARIABLE will evaluate to "foo"

Using VARIABLE ?= val means that you only set the value of VARIABLE if VARIABLE is not set already. If it's not set already, the setting of the value is deferred until VARIABLE is used (as in example 1).

VARIABLE += value just appends value to VARIABLE. The actual value of value is determined as it was when it was initially set, using either = or :=.

iptables block access to port 8000 except from IP address

You can always use iptables to delete the rules. If you have a lot of rules, just output them using the following command.

iptables-save > myfile

vi to edit them from the commend line. Just use the "dd" to delete the lines you no longer want.

iptables-restore < myfile and you're good to go.  

REMEMBER THAT IF YOU DON'T CONFIGURE YOUR OS TO SAVE THE RULES TO A FILE AND THEN LOAD THE FILE DURING THE BOOT THAT YOUR RULES WILL BE LOST.

PHP Parse error: syntax error, unexpected T_PUBLIC

The public keyword is used only when declaring a class method.

Since you're declaring a simple function and not a class you need to remove public from your code.

How to check if a file is a valid image file?

One option is to use the filetype package.

Installation

python -m pip install filetype

Advantages

  1. Quick: Does its work by loading the first few bytes of your image (check on the magic number)
  2. Supports different mime type: Images, Videos, Fonts, Audio, Archives.

Example

filetype >= 1.0.7

import filetype

filename = "/path/to/file.jpg"

if filetype.is_image(filename):
    print(f"{filename} is a valid image...")
elif filetype.is_video(filename):
    print(f"{filename} is a valid video...")

filetype <= 1.0.6

import filetype

filename = "/path/to/file.jpg"

if filetype.image(filename):
    print(f"{filename} is a valid image...")
elif filetype.video(filename):
    print(f"{filename} is a valid video...")

Additional information on the official repo: https://github.com/h2non/filetype.py

Best way to display data via JSON using jQuery

Perfect! Thank you Jay, below is my HTML:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Facebook like ajax post - jQuery - ryancoughlin.com</title>
<link rel="stylesheet" href="../css/screen.css" type="text/css" media="screen, projection" />
<link rel="stylesheet" href="../css/print.css" type="text/css" media="print" />
<!--[if IE]><link rel="stylesheet" href="../css/ie.css" type="text/css" media="screen, projection"><![endif]-->
<link href="../css/highlight.css" rel="stylesheet" type="text/css" media="screen" />
<script src="js/jquery.js" type="text/javascript" charset="utf-8"></script>
<script type="text/javascript">
/* <![CDATA[ */
$(document).ready(function(){
    $.getJSON("readJSON.php",function(data){
        $.each(data.post, function(i,post){
            content += '<p>' + post.post_author + '</p>';
            content += '<p>' + post.post_content + '</p>';
            content += '<p' + post.date + '</p>';
            content += '<br/>';
            $(content).appendTo("#posts");
        });
    });   
});
/* ]]> */
</script>
</head>
<body>
        <div class="container">
                <div class="span-24">
                       <h2>Check out the following posts:</h2>
                        <div id="posts">
                        </di>
                </div>
        </div>
</body>
</html>

And my JSON outputs:

{ posts: [{"id":"1","date_added":"0001-02-22 00:00:00","post_content":"This is a post","author":"Ryan Coughlin"}]}

I get this error, when I run my code:

object is undefined
http://localhost:8888/rks/post/js/jquery.js
Line 19

How to convert NSData to byte array in iPhone?

You can't declare an array using a variable so Byte byteData[len]; won't work. If you want to copy the data from a pointer, you also need to memcpy (which will go through the data pointed to by the pointer and copy each byte up to a specified length).

Try:

NSData *data = [NSData dataWithContentsOfFile:filePath];
NSUInteger len = [data length];
Byte *byteData = (Byte*)malloc(len);
memcpy(byteData, [data bytes], len);

This code will dynamically allocate the array to the correct size (you must free(byteData) when you're done) and copy the bytes into it.

You could also use getBytes:length: as indicated by others if you want to use a fixed length array. This avoids malloc/free but is less extensible and more prone to buffer overflow issues so I rarely ever use it.

How to assign an exec result to a sql variable?

This will work if you wish to simply return an integer:

DECLARE @ResultForPos INT 
EXEC @ResultForPos = storedprocedureName 'InputParameter'
SELECT @ResultForPos

Check if an element contains a class in JavaScript?

The easy and effective solution is trying .contains method.

test.classList.contains(testClass);

Select mySQL based only on month and year

SELECT * FROM projects WHERE YEAR(Date) = 2011 AND MONTH(Date) = 5

How to remove all the punctuation in a string? (Python)

A really simple implementation is:

out = "".join(c for c in asking if c not in ('!','.',':'))

and keep adding any other types of punctuation.

A more efficient way would be

import string
stringIn = "string.with.punctuation!"
out = stringIn.translate(stringIn.maketrans("",""), string.punctuation)

Edit: There is some more discussion on efficiency and other implementations here: Best way to strip punctuation from a string in Python

How to see full absolute path of a symlink

You can use awk with a system call readlink to get the equivalent of an ls output with full symlink paths. For example:

ls | awk '{printf("%s ->", $1); system("readlink -f " $1)}'

Will display e.g.

thin_repair ->/home/user/workspace/boot/usr/bin/pdata_tools
thin_restore ->/home/user/workspace/boot/usr/bin/pdata_tools
thin_rmap ->/home/user/workspace/boot/usr/bin/pdata_tools
thin_trim ->/home/user/workspace/boot/usr/bin/pdata_tools
touch ->/home/user/workspace/boot/usr/bin/busybox
true ->/home/user/workspace/boot/usr/bin/busybox

Angular EXCEPTION: No provider for Http

Import HttpModule in your app.module.ts file.

import { HttpModule } from '@angular/http';
import { YourHttpTestService } from '../services/httpTestService';

Also remember to declare HttpModule under imports like below:

imports: [
    BrowserModule,
    HttpModule
  ],

Could not resolve this reference. Could not locate the assembly

If anyone face this issue with some nuget packages, you can fix that by reinstalling the packages using the Package Manager Console:

Update-Package -reinstall 

In c# what does 'where T : class' mean?

it means that the type used as T when the generic method is used must be a class - i.e. it cannot be a struct or built in number like int or double

// Valid:
var myStringList = DoThis<string>();
// Invalid - compile error
var myIntList = DoThis<int>();

Python variables as keys to dict

for i in ('apple', 'banana', 'carrot'):
    fruitdict[i] = locals()[i]

PHPExcel auto size column width

// Auto-size columns for all worksheets
foreach ($objPHPExcel->getWorksheetIterator() as $worksheet) {
    foreach ($worksheet->getColumnIterator() as $column) {
        $worksheet
            ->getColumnDimension($column->getColumnIndex())
            ->setAutoSize(true);
    } 
}

Is there a 'box-shadow-color' property?

A quick and copy/paste you can use for Chrome and Firefox would be: (change the stuff after the # to change the color)

-moz-border-radius: 10px;
-webkit-border-radius: 10px;
-khtml-border-radius: 10px;
-border-radius: 10px;
-moz-box-shadow: 0 0 15px 5px #666;
-webkit-box-shadow: 0 0 15px 05px #666;

Matt Roberts' answer is correct for webkit browsers (safari, chrome, etc), but I thought someone out there might want a quick answer rather than be told to learn to program to make some shadows.

Getting a list of associative array keys

Simple jQuery way:

This is what I use:

DictionaryObj being the JavaScript dictionary object you want to go through. And value, key of course being the names of them in the dictionary.

$.each(DictionaryObj, function (key, value) {
    $("#storeDuplicationList")
        .append($("<li></li>")
        .attr("value", key)
        .text(value));
});

ORA-06502: PL/SQL: numeric or value error: character string buffer too small

PL/SQL: numeric or value error: character string buffer too small

is due to the fact that you declare a string to be of a fixed length (say 20), and at some point in your code you assign it a value whose length exceeds what you declared.

for example:

myString VARCHAR2(20);
myString :='abcdefghijklmnopqrstuvwxyz'; --length 26

will fire such an error

WSDL/SOAP Test With soapui

I faced the same exception while trying to test my web-services deployed to WSO2 ESB.

WSO2 generated both wsdl and wsdl2. I tried to pass a wsdl2 URL and got the above exception. Quick googling showed me, that one of differences between wsdl1.1 and wsdl2.0 is replacing 'definitions' element with 'description'. Also, I found out, that SoapUI does not support wsdl2.

Therefore, for me the solution was to use wsdl1 url instead of wsdl2.

How to get a user's time zone?

Swift 4, 4.2 & 5

var timeZone : String = String()

override func viewDidLoad() {
    super.viewDidLoad()
    timeZone = getCurrentTimeZone()
    print(timeZone)
}

func getCurrentTimeZone() -> String {
        let localTimeZoneAbbreviation: Int = TimeZone.current.secondsFromGMT()
        let items = (localTimeZoneAbbreviation / 3600)
        return "\(items)"
}

How to embed small icon in UILabel

try this way...

  self.lbl.text=@"Drawble Left";
    UIImageView *img=[[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 20, 20)];
    img.image=[UIImage imageNamed:@"Star.png"];
    [self.lbl addSubview:img];

How do you display code snippets in MS Word preserving format and syntax highlighting?

You can use VS code to keep code format and highlighting. Directly copy and paste code from VS.enter image description here

How to pass a value to razor variable from javascript variable?

here is my solution that works:

in my form i use:

@using (Html.BeginForm("RegisterOrder", "Account", FormMethod.Post, new { @class = "form", role = "form" }))
  {

   @Html.TextBoxFor(m => m.Email, new { @class = "form-control" })

   @Html.HiddenFor(m => m.quantity, new { id = "quantity", Value = 0 })

  }

in my file.js I get the quantity from a GET request and pass the variable as follows to the form:

    $http({
        method: 'Get',
        url: "https://xxxxxxx.azurewebsites.net/api/quantity/" + usr
    })
        .success(function (data){

            setQuantity(data.number);

            function setQuantity(number) {
                $('#quantity').val(number);
            }

        });

Python: PIP install path, what is the correct location for this and other addons?

Since pip is an executable and which returns path of executables or filenames in environment. It is correct. Pip module is installed in site-packages but the executable is installed in bin.

How to make the HTML link activated by clicking on the <li>?

a {
  display: block;
  position: relative;
}

I think that is all you need.

How can I remove the search bar and footer added by the jQuery DataTables plugin?

I think the simplest way is:

<th data-searchable="false">Column</th>

You can edit only the table you have to modify, without change common CSS or JS.

Doing a join across two databases with different collations on SQL Server and getting an error

You can use the collate clause in a query (I can't find my example right now, so my syntax is probably wrong - I hope it points you in the right direction)

select sone_field collate SQL_Latin1_General_CP850_CI_AI
  from table_1
    inner join table_2
      on (table_1.field collate SQL_Latin1_General_CP850_CI_AI = table_2.field)
  where whatever

Extract csv file specific columns to list in Python

import csv
from sys import argv

d = open("mydata.csv", "r")

db = []

for line in csv.reader(d):
    db.append(line)

# the rest of your code with 'db' filled with your list of lists as rows and columbs of your csv file.

PHP save image file

No need to create a GD resource, as someone else suggested.

$input = 'http://images.websnapr.com/?size=size&key=Y64Q44QLt12u&url=http://google.com';
$output = 'google.com.jpg';
file_put_contents($output, file_get_contents($input));

Note: this solution only works if you're setup to allow fopen access to URLs. If the solution above doesn't work, you'll have to use cURL.

Replace all elements of Python NumPy Array that are greater than some value

I think both the fastest and most concise way to do this is to use NumPy's built-in Fancy indexing. If you have an ndarray named arr, you can replace all elements >255 with a value x as follows:

arr[arr > 255] = x

I ran this on my machine with a 500 x 500 random matrix, replacing all values >0.5 with 5, and it took an average of 7.59ms.

In [1]: import numpy as np
In [2]: A = np.random.rand(500, 500)
In [3]: timeit A[A > 0.5] = 5
100 loops, best of 3: 7.59 ms per loop

Negative list index?

List indexes of -x mean the xth item from the end of the list, so n[-1] means the last item in the list n. Any good Python tutorial should have told you this.

It's an unusual convention that only a few other languages besides Python have adopted, but it is extraordinarily useful; in any other language you'll spend a lot of time writing n[n.length-1] to access the last item of a list.

Launch Android application without main Activity and start Service on launching application

Android Studio Version 2.3

You can create a Service without a Main Activity by following a few easy steps. You'll be able to install this app through Android Studio and debug it like a normal app.

First, create a project in Android Studio without an activity. Then create your Service class and add the service to your AndroidManifest.xml

<application android:allowBackup="true"
    android:label="@string/app_name"
    android:icon="@mipmap/ic_launcher"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <service android:name="com.whatever.myservice.MyService">
        <intent-filter>
            <action android:name="com.whatever.myservice.MyService" />
        </intent-filter>
    </service>
</application>

Now, in the drop down next to the "Run" button(green arrow), go to "edit configurations" and within the "Launch Options" choose "Nothing". This will allow you to install your Service without Android Studio complaining about not having a Main Activity.

Once installed, the service will NOT be running but you will be able to start it with this adb shell command...

am startservice -n com.whatever.myservice/.MyService

Can check it's running with...

ps | grep whatever

I haven't tried yet but you can likely have Android Studio automatically start the service too. This would be done in that "Edit Configurations" menu.

How to pass a textbox value from view to a controller in MVC 4?

You can use simple form:

@using(Html.BeginForm("Update", "Shopping"))
{
    <input type="text" id="ss" name="qty" value="@item.Quantity"/>
    ...
    <input type="submit" value="Update" />
}

And add here attribute:

[HttpPost]
public ActionResult Update(string id, string productid, int qty, decimal unitrate)

Proper usage of Java -D command-line parameters

I suspect the problem is that you've put the "-D" after the -jar. Try this:

java -Dtest="true" -jar myApplication.jar

From the command line help:

java [-options] -jar jarfile [args...]

In other words, the way you've got it at the moment will treat -Dtest="true" as one of the arguments to pass to main instead of as a JVM argument.

(You should probably also drop the quotes, but it may well work anyway - it probably depends on your shell.)

scroll up and down a div on button click using jquery

Just to add to other comments - it would be worth while to disable scrolling up whilst at the top of the page. If the user accidentally scrolls up whilst already at the top they would have to scroll down twice to start

if(scrolled != 0){
  $("#upClick").on("click" ,function(){
     scrolled=scrolled-300;
        $(".cover").animate({
          scrollTop:  scrolled
     });
  });
}

Oracle SQL update based on subquery between two tables

Try it ..

UPDATE PRODUCTION a
SET (name, count) = (
SELECT name, count
        FROM STAGING b
        WHERE a.ID = b.ID)
WHERE EXISTS (SELECT 1
    FROM STAGING b
    WHERE a.ID=b.ID
 );

How to increase application heap size in Eclipse?

Find the Run button present on the top of the Eclipse, then select Run Configuration -> Arguments, in VM arguments section just mention the heap size you want to extend as below:

-Xmx1024m

Force HTML5 youtube video

I tried using the iframe embed code and the HTML5 player appeared, however, for some reason the iframe was completely breaking my site.

I messed around with the old object embed code and it works perfectly fine. So if you're having problems with the iframe here's the code i used:

<object width="640" height="360">
<param name="movie" value="http://www.youtube.com/embed/VIDEO_ID?html5=1&amp;rel=0&amp;hl=en_US&amp;version=3"/>
<param name="allowFullScreen" value="true"/>
<param name="allowscriptaccess" value="always"/>
<embed width="640" height="360" src="http://www.youtube.com/embed/VIDEO_ID?html5=1&amp;rel=0&amp;hl=en_US&amp;version=3" class="youtube-player" type="text/html" allowscriptaccess="always" allowfullscreen="true"/>
</object>

hope this is useful for someone

process.waitFor() never returns

There are several possibilities:

  1. You haven't consumed all the output on the process's stdout.
  2. You haven't consumed all the output on the process's stderr.
  3. The process is waiting for input from you and you haven't provided it, or you haven't closed the process's stdin.
  4. The process is spinning in a hard loop.

How do I know the script file name in a Bash script?

somthing like this?

export LC_ALL=en_US.UTF-8
#!/bin/bash
#!/bin/sh

#----------------------------------------------------------------------
start_trash(){
ver="htrash.sh v0.0.4"
$TRASH_DIR  # url to trash $MY_USER
$TRASH_SIZE # Show Trash Folder Size

echo "Would you like to empty Trash  [y/n]?"
read ans
if [ $ans = y -o $ans = Y -o $ans = yes -o $ans = Yes -o $ans = YES ]
then
echo "'yes'"
cd $TRASH_DIR && $EMPTY_TRASH
fi
if [ $ans = n -o $ans = N -o $ans = no -o $ans = No -o $ans = NO ]
then
echo "'no'"
fi
 return $TRUE
} 
#-----------------------------------------------------------------------

start_help(){
echo "HELP COMMANDS-----------------------------"
echo "htest www                 open a homepage "
echo "htest trash               empty trash     "
 return $TRUE
} #end Help
#-----------------------------------------------#

homepage=""

return $TRUE
} #end cpdebtemp

# -Case start
# if no command line arg given
# set val to Unknown
if [ -z $1 ]
then
  val="*** Unknown  ***"
elif [ -n $1 ]
then
# otherwise make first arg as val
  val=$1
fi
# use case statement to make decision for rental
case $val in
   "trash") start_trash ;;
   "help") start_help ;;
   "www") firefox $homepage ;;
   *) echo "Sorry, I can not get a $val   for you!";;
esac
# Case stop

What is secret key for JWT based authentication and how to generate it?

You can write your own generator. The secret key is essentially a byte array. Make sure that the string that you convert to a byte array is base64 encoded.

In Java, you could do something like this.

String key = "random_secret_key";
String base64Key = DatatypeConverter.printBase64Binary(key.getBytes());
byte[] secretBytes = DatatypeConverter.parseBase64Binary(base64Key);

Best way to require all files from a directory in ruby?

I'm a few years late to the party, but I kind of like this one-line solution I used to get rails to include everything in app/workers/concerns:

Dir[ Rails.root.join *%w(app workers concerns *) ].each{ |f| require f }

Cannot open include file: 'unistd.h': No such file or directory

If you're using ZLib in your project, then you need to find :

#if 1

in zconf.h and replace(uncomment) it with :

#if HAVE_UNISTD_H /* ...the rest of the line

If it isn't ZLib I guess you should find some alternative way to do this. GL.

What's the CMake syntax to set and use variables?

$ENV{FOO} for usage, where FOO is being picked up from the environment variable. otherwise use as ${FOO}, where FOO is some other variable. For setting, SET(FOO "foo") would be used in CMake.

Can you disable tabs in Bootstrap?

I added the following Javascript to prevent clicks on disabled links:

$(".nav-tabs a[data-toggle=tab]").on("click", function(e) {
  if ($(this).hasClass("disabled")) {
    e.preventDefault();
    return false;
  }
});

Is it possible to capture the stdout from the sh DSL command in the pipeline

Now, the sh step supports returning stdout by supplying the parameter returnStdout.

// These should all be performed at the point where you've
// checked out your sources on the slave. A 'git' executable
// must be available.
// Most typical, if you're not cloning into a sub directory
gitCommit = sh(returnStdout: true, script: 'git rev-parse HEAD').trim()
// short SHA, possibly better for chat notifications, etc.
shortCommit = gitCommit.take(6)

See this example.

Nested objects in javascript, best practices

var defaultsettings = {
    ajaxsettings: {
        ...
    },
    uisettings: {
        ...
    }
};

how to take user input in Array using java?

int length;
    Scanner input = new Scanner(System.in);
    System.out.println("How many numbers you wanna enter?");
    length = input.nextInt();
    System.out.println("Enter " + length + " numbers, one by one...");
    int[] arr = new int[length];
    for (int i = 0; i < arr.length; i++) {
        System.out.println("Enter the number " + (i + 1) + ": ");
        //Below is the way to collect the element from the user
        arr[i] = input.nextInt();

        // auto generate the elements
        //arr[i] = (int)(Math.random()*100);
    }
    input.close();
    System.out.println(Arrays.toString(arr));

Create table with jQuery - append

This line:

$('#here_table').append( '<tr><td>' + 'result' +  i + '</td></tr>' );

Appends to the div#here_table not the new table.

There are several approaches:

/* Note that the whole content variable is just a string */
var content = "<table>"
for(i=0; i<3; i++){
    content += '<tr><td>' + 'result ' +  i + '</td></tr>';
}
content += "</table>"

$('#here_table').append(content);

But, with the above approach it is less manageable to add styles and do stuff dynamically with <table>.

But how about this one, it does what you expect nearly great:

var table = $('<table>').addClass('foo');
for(i=0; i<3; i++){
    var row = $('<tr>').addClass('bar').text('result ' + i);
    table.append(row);
}

$('#here_table').append(table);

Hope this would help.

Extracting jar to specified directory

It's better to do this.

Navigate to the folder structure you require

Use the command

jar -xvf  'Path_to_ur_Jar_file'

MISCONF Redis is configured to save RDB snapshots

After banging my head through so many SO questions finally - for me @Axel Advento' s answer worked but with few extra steps - I was still facing the permission issues.
I had to switch user to redis, create a new dir in it's home dir and then set it as redis's dir.

sudo su - redis -s /bin/bash
mkdir redis_dir
redis-cli CONFIG SET dir $(realpath redis_dir)
exit # to logout from redis user (optional)

How do I remove objects from a JavaScript associative array?

You are using Object, and you don't have an associative array to begin with. With an associative array, adding and removing items goes like this:

    Array.prototype.contains = function(obj)
    {
        var i = this.length;
        while (i--)
        {
            if (this[i] === obj)
            {
                return true;
            }
        }
        return false;
    }


    Array.prototype.add = function(key, value)
    {
        if(this.contains(key))
            this[key] = value;
        else
        {
            this.push(key);
            this[key] = value;
        }
    }


    Array.prototype.remove = function(key)
    {
        for(var i = 0; i < this.length; ++i)
        {
            if(this[i] == key)
            {
                this.splice(i, 1);
                return;
            }
        }
    }



    // Read a page's GET URL variables and return them as an associative array.
    function getUrlVars()
    {
        var vars = [], hash;
        var hashes = window.location.href.slice(window.location.href.indexOf('?') + 1).split('&');

        for(var i = 0; i < hashes.length; i++)
        {
            hash = hashes[i].split('=');
            vars.push(hash[0]);
            vars[hash[0]] = hash[1];
        }

        return vars;
    }


    function ForwardAndHideVariables() {
        var dictParameters = getUrlVars();

        dictParameters.add("mno", "pqr");
        dictParameters.add("mno", "stfu");

        dictParameters.remove("mno");


        for(var i = 0; i < dictParameters.length; i++)
        {
            var key = dictParameters[i];
            var value = dictParameters[key];
            alert(key + "=" + value);
        }
        // And now forward with HTTP-POST
        aa_post_to_url("Default.aspx", dictParameters);
    }


    function aa_post_to_url(path, params, method) {
        method = method || "post";

        var form = document.createElement("form");

        // Move the submit function to another variable
        // so that it doesn't get written over if a parameter name is 'submit'
        form._submit_function_ = form.submit;

        form.setAttribute("method", method);
        form.setAttribute("action", path);

        for(var i = 0; i < params.length; i++)
        {
            var key = params[i];

            var hiddenField = document.createElement("input");
            hiddenField.setAttribute("type", "hidden");
            hiddenField.setAttribute("name", key);
            hiddenField.setAttribute("value", params[key]);

            form.appendChild(hiddenField);
        }

        document.body.appendChild(form);
        form._submit_function_(); // Call the renamed function
    }

How to read file from relative path in Java project? java.io.File cannot find the path specified

For me actually the problem is the File object's class path is from <project folder path> or ./src, so use File file = new File("./src/xxx.txt"); solved my problem

How to show Alert Message like "successfully Inserted" after inserting to DB using ASp.net MVC3

Personally I'd go with AJAX.

If you cannot switch to @Ajax... helpers, I suggest you to add a couple of properties in your model

public bool TriggerOnLoad { get; set; }
public string TriggerOnLoadMessage { get; set: }

Change your view to a strongly typed Model via

@using MyModel

Before returning the View, in case of successfull creation do something like

MyModel model = new MyModel();
model.TriggerOnLoad = true;
model.TriggerOnLoadMessage = "Object successfully created!";
return View ("Add", model);

then in your view, add this

@{
   if (model.TriggerOnLoad) {
   <text>
   <script type="text/javascript">
     alert('@Model.TriggerOnLoadMessage');
   </script>
   </text>
   }
}

Of course inside the tag you can choose to do anything you want, event declare a jQuery ready function:

$(document).ready(function () {
   alert('@Model.TriggerOnLoadMessage');
});

Please remember to reset the Model properties upon successfully alert emission.

Another nice thing about MVC is that you can actually define an EditorTemplate for all this, and then use it in your view via:

@Html.EditorFor (m => m.TriggerOnLoadMessage)

But in case you want to build up such a thing, maybe it's better to define your own C# class:

class ClientMessageNotification {
    public bool TriggerOnLoad { get; set; }
    public string TriggerOnLoadMessage { get; set: }
}

and add a ClientMessageNotification property in your model. Then write EditorTemplate / DisplayTemplate for the ClientMessageNotification class and you're done. Nice, clean, and reusable.

How to get whole and decimal part of a number?

The floor() method doesn't work for negative numbers. This works every time:

$num = 5.7;
$whole = (int) $num;  // 5
$frac  = $num - $whole;  // .7

...also works for negatives (same code, different number):

$num = -5.7;
$whole = (int) $num;  // -5
$frac  = $num - $whole;  // -.7

Ansible: filter a list by its attributes

Not necessarily better, but since it's nice to have options here's how to do it using Jinja statements:

- debug:
    msg: "{% for address in network.addresses.private_man %}\
        {% if address.type == 'fixed' %}\
          {{ address.addr }}\
        {% endif %}\
      {% endfor %}"

Or if you prefer to put it all on one line:

- debug:
    msg: "{% for address in network.addresses.private_man if address.type == 'fixed' %}{{ address.addr }}{% endfor %}"

Which returns:

ok: [localhost] => {
    "msg": "172.16.1.100"
}

Passing arguments to an interactive program non-interactively

Many ways

pipe your input

echo "yes
no
maybe" | your_program

redirect from a file

your_program < answers.txt

use a here document (this can be very readable)

your_program << ANSWERS
yes
no
maybe
ANSWERS

use a here string

your_program <<< $'yes\nno\nmaybe\n'

How to update npm

Check your node version node -v and your npm version npm -v Then To update your npm, type this into your terminal : sudo npm install npm@latest -g

N.B: Debian Based OS{ubuntu or Linux mint}

What HTTP status response code should I use if the request is missing a required parameter?

It could be argued that a 404 Not Found should be used since the resource specified could not be found.

Android: I am unable to have ViewPager WRAP_CONTENT

Nothing of suggested above worked for me. My use case is having 4 custom ViewPagers in ScrollView. Top of them is measured based on aspect ratio and the rest just has layout_height=wrap_content. I've tried cybergen , Daniel López Lacalle solutions. None of them work fully for me.

My guess why cybergen doesn't work on page > 1 is because it calculates height of pager based on page 1, that is hidden if you scroll further.

Both cybergen and Daniel López Lacalle suggestions have weird behavior in my case: 2 of 3 are loaded ok and 1 randomly height is 0. Appears that onMeasure was called before children were populated. So I came up with a mixture of these 2 answers + my own fixes:

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    if (getLayoutParams().height == ViewGroup.LayoutParams.WRAP_CONTENT) {
        // find the first child view
        View view = getChildAt(0);
        if (view != null) {
            // measure the first child view with the specified measure spec
            view.measure(widthMeasureSpec, heightMeasureSpec);
            int h = view.getMeasuredHeight();
            setMeasuredDimension(getMeasuredWidth(), h);
            //do not recalculate height anymore
            getLayoutParams().height = h;
        }
    }
}

Idea is to let ViewPager calculate children's dimensions and save calculated height of first page in layout params of the ViewPager. Don't forget to set fragment's layout height to wrap_content otherwise you can get height=0. I've used this one:

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

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="horizontal" android:layout_width="match_parent"
    android:layout_height="wrap_content">
        <!-- Childs are populated in fragment -->
</LinearLayout>

Please note that this solution works great if all of your pages have same height. Otherwise you need to recalculate ViewPager height based on current child active. I don't need it, but if you suggest the solution I would be happy to update the answer.

How can I use grep to find a word inside a folder?

grep -nr string my_directory

Additional notes: this satisfies the syntax grep [options] string filename because in Unix-like systems, a directory is a kind of file (there is a term "regular file" to specifically refer to entities that are called just "files" in Windows).

grep -nr string reads the content to search from the standard input, that is why it just waits there for input from you, and stops doing so when you press ^C (it would stop on ^D as well, which is the key combination for end-of-file).

Creating a ZIP archive in memory using System.IO.Compression

Just in case, if anyone wants to save a dynamic zip file through SaveFileDialog.

        var logFileName = "zip_filename.zip";
        appLogSaver.FileName = logFileName;
        appLogSaver.Filter = "LogFiles|*.zip";
        appLogSaver.DefaultExt = "zip";
        DialogResult resDialog = appLogSaver.ShowDialog();

        if (resDialog.ToString() == "OK")
        {
            System.IO.FileStream fs = (System.IO.FileStream)appLogSaver.OpenFile();

            using (var memoryStream = new MemoryStream())
            {
                using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
                {
                    var demoFile = archive.CreateEntry("foo.txt");
                    using (var entryStream = demoFile.Open())
                    {
                        using (var streamWriter = new StreamWriter(entryStream))
                        {
                            //read your existing file and put the content here 
                            streamWriter.Write("Bar!");
                        }
                    }

                    var demoFile2 = archive.CreateEntry("foo2.txt");
                    using (var entryStream = demoFile2.Open())
                    {
                        using (var streamWriter = new StreamWriter(entryStream))
                        {
                            streamWriter.Write("Bar2!");
                        }
                    }
                }

                memoryStream.Seek(0, SeekOrigin.Begin);
                memoryStream.CopyTo(fs);
            }
            fs.Close();
        }

Not an enclosing class error Android Studio

replace code in onClick() method with this:

Intent myIntent = new Intent(this, Katra_home.class);
startActivity(myIntent);

How can I calculate the time between 2 Dates in typescript

// TypeScript

const today = new Date();
const firstDayOfYear = new Date(today.getFullYear(), 0, 1);

// Explicitly convert Date to Number
const pastDaysOfYear = ( Number(today) - Number(firstDayOfYear) );

How to add elements to a list in R (loop)

The following adds elements to a list in a loop.

l<-c()
i=1

while(i<100) {

    b<-i
    l<-c(l,b)
    i=i+1
}

How to hide Bootstrap modal with javascript?

this can be done in just HTML:

data-dismiss="modal"

<button type="button" class="btn btn-secondary" data-dismiss="modal">Save</button>

CMake complains "The CXX compiler identification is unknown"

Your /home/gnu/bin/c++ seem to require additional flag to link things properly and CMake doesn't know about that.

To use /usr/bin/c++ as your compiler run cmake with -DCMAKE_CXX_COMPILER=/usr/bin/c++.

Also, CMAKE_PREFIX_PATH variable sets destination dir where your project' files should be installed. It has nothing to do with CMake installation prefix and CMake itself already know this.

How to completely DISABLE any MOUSE CLICK

something like:

    $('#doc').click(function(e){
       e.preventDefault()
       e.stopImmediatePropagation() //charles ma is right about that, but stopPropagation isn't also needed
});

should do the job you could also bind more mouse events with replacing for: edit: add this in the feezing part

    $('#doc').bind('click mousedown dblclick',function(e){
       e.preventDefault()
       e.stopImmediatePropagation()
});

and this in the unfreezing:

  $('#doc').unbind();

PHP Function with Optional Parameters

If you are commonly just passing in the 8th value, you can reorder your parameters so it is first. You only need to specify parameters up until the last one you want to set.

If you are using different values, you have 2 options.

One would be to create a set of wrapper functions that take different parameters and set the defaults on the others. This is useful if you only use a few combinations, but can get very messy quickly.

The other option is to pass an array where the keys are the names of the parameters. You can then just check if there is a value in the array with a key, and if not use the default. But again, this can get messy and add a lot of extra code if you have a lot of parameters.

ASP.net Getting the error "Access to the path is denied." while trying to upload files to my Windows Server 2008 R2 Web server

Right click on your folder on your server or local machine and give full permissions to

IIS_IUSRS

that's it.

How to declare and initialize a static const array as a class member?

You are mixing pointers and arrays. If what you want is an array, then use an array:

struct test {
   static int data[10];        // array, not pointer!
};
int test::data[10] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };

If on the other hand you want a pointer, the simplest solution is to write a helper function in the translation unit that defines the member:

struct test {
   static int *data;
};
// cpp
static int* generate_data() {            // static here is "internal linkage"
   int * p = new int[10];
   for ( int i = 0; i < 10; ++i ) p[i] = 10*i;
   return p;
}
int *test::data = generate_data();

css3 text-shadow in IE9

As IE9 does not support CSS3 text-shadow, I would just use the filter property for IE instead. Live example: http://jsfiddle.net/dmM2S/

text-shadow:1px 1px 1px red; /* CSS3 */

can be replaced with

filter: Shadow(Color=red, Direction=130, Strength=1); /* IE Proprietary Filter*/

You can get the results to be very similar.

How to launch jQuery Fancybox on page load?

You can put link like this (it will be hidden. May be before </body>)

<a id="clickbanner" href="image.jpg" rel="gallery"></a>

And working rel attribute or class like this

$(document).ready(function() {
    $("a[rel=gallery]").fancybox({
        openEffect  : 'elastic',
        closeEffect : 'elastic',
        maxWidth    : 800,
        maxHeight   : 600
    });
});

Just do it with jquery trigger function

$( window ).load(function() {
  $("#clickbanner").trigger('click');
});

How to count number of files in each directory?

This prints the file count per directory for the current directory level:

du -a | cut -d/ -f2 | sort | uniq -c | sort -nr

Is it possible to append to innerHTML without destroying descendants' event listeners?

something.innerHTML += 'add whatever you want';

it worked for me. I added a button to an input text using this solution

What is the most robust way to force a UIView to redraw?

Well I know this might be a big change or even not suitable for your project, but did you consider not performing the push until you already have the data? That way you only need to draw the view once and the user experience will also be better - the push will move in already loaded.

The way you do this is in the UITableView didSelectRowAtIndexPath you asynchronously ask for the data. Once you receive the response, you manually perform the segue and pass the data to your viewController in prepareForSegue. Meanwhile you may want to show some activity indicator, for simple loading indicator check https://github.com/jdg/MBProgressHUD

Storing JSON in database vs. having a new column for each key

Updated 4 June 2017

Given that this question/answer have gained some popularity, I figured it was worth an update.

When this question was originally posted, MySQL had no support for JSON data types and the support in PostgreSQL was in its infancy. Since 5.7, MySQL now supports a JSON data type (in a binary storage format), and PostgreSQL JSONB has matured significantly. Both products provide performant JSON types that can store arbitrary documents, including support for indexing specific keys of the JSON object.

However, I still stand by my original statement that your default preference, when using a relational database, should still be column-per-value. Relational databases are still built on the assumption of that the data within them will be fairly well normalized. The query planner has better optimization information when looking at columns than when looking at keys in a JSON document. Foreign keys can be created between columns (but not between keys in JSON documents). Importantly: if the majority of your schema is volatile enough to justify using JSON, you might want to at least consider if a relational database is the right choice.

That said, few applications are perfectly relational or document-oriented. Most applications have some mix of both. Here are some examples where I personally have found JSON useful in a relational database:

  • When storing email addresses and phone numbers for a contact, where storing them as values in a JSON array is much easier to manage than multiple separate tables

  • Saving arbitrary key/value user preferences (where the value can be boolean, textual, or numeric, and you don't want to have separate columns for different data types)

  • Storing configuration data that has no defined schema (if you're building Zapier, or IFTTT and need to store configuration data for each integration)

I'm sure there are others as well, but these are just a few quick examples.

Original Answer

If you really want to be able to add as many fields as you want with no limitation (other than an arbitrary document size limit), consider a NoSQL solution such as MongoDB.

For relational databases: use one column per value. Putting a JSON blob in a column makes it virtually impossible to query (and painfully slow when you actually find a query that works).

Relational databases take advantage of data types when indexing, and are intended to be implemented with a normalized structure.

As a side note: this isn't to say you should never store JSON in a relational database. If you're adding true metadata, or if your JSON is describing information that does not need to be queried and is only used for display, it may be overkill to create a separate column for all of the data points.

Can't create project on Netbeans 8.2

If you run in linux, open file netbeans.conf using nano or anything else.

nano netbeans-8.2/etc/netbeans.conf

and edit jdkhome or directory for jdk

netbeans_jdkhome="/usr/lib/jvm/java-1.8.0-openjdk-amd64"

you can check your jdk version with

java -version

or

ls /usr/lib/jvm

How to set time to midnight for current day?

Using some of the above recommendations, the following function and code is working for search a date range:

Set date with the time component set to 00:00:00

public static DateTime GetDateZeroTime(DateTime date)
{
    return new DateTime(date.Year, date.Month, date.Day, 0, 0, 0);
}

Usage

var modifieddatebegin = Tools.Utilities.GetDateZeroTime(form.modifieddatebegin);

var modifieddateend = Tools.Utilities.GetDateZeroTime(form.modifieddateend.AddDays(1));

How to convert ActiveRecord results into an array of hashes

For current ActiveRecord (4.2.4+) there is a method to_hash on the Result object that returns an array of hashes. You can then map over it and convert to symbolized hashes:

# Get an array of hashes representing the result (column => value):
result.to_hash
# => [{"id" => 1, "title" => "title_1", "body" => "body_1"},
      {"id" => 2, "title" => "title_2", "body" => "body_2"},
      ...
     ]

result.to_hash.map(&:symbolize_keys)
# => [{:id => 1, :title => "title_1", :body => "body_1"},
      {:id => 2, :title => "title_2", :body => "body_2"},
      ...
     ]

See the ActiveRecord::Result docs for more info.

Executing multiple commands from a Windows cmd script

I have just been doing the exact same(ish) task of creating a batch script to run maven test scripts. The problem is that calling maven scrips with mvn clean install ... is itself a script and so needs to be done with call mvn clean install.

Code that will work

rem run a maven clean install
cd C:\rbe-ui-test-suite 
call mvn clean install
rem now run through all the test scripts
call mvn clean install -Prun-integration-tests -Dpattern=tc-login
call mvn clean install -Prun-integration-tests -Dpattern=login-1

Note rather the use of call. This will allow the use of consecutive maven scripts in the batch file.

Changing the sign of a number in PHP?

I think Gumbo's answer is just fine. Some people prefer this fancy expression that does the same thing:

$int = (($int > 0) ? -$int : $int);

EDIT: Apparently you are looking for a function that will make negatives positive as well. I think these answers are the simplest:

/* I am not proposing you actually use functions called
   "makeNegative" and "makePositive"; I am just presenting
   the most direct solution in the form of two clearly named
   functions. */
function makeNegative($num) { return -abs($num); }
function makePositive($num) { return abs($num); }

Rails: How to reference images in CSS within Rails 4

Interestingly, if I use 'background-image', it does not work:

background-image: url('picture.png');

But just 'background', it does:

background: url('picture.png');

Rerender view on browser resize with React

Just to improve on @senornestor's solution to use forceUpdate and @gkri's solution to removing the resize event listener on component unmount:

  1. don't forget to throttle (or debounce) the call to resize
  2. make sure to bind(this) in the constructor
import React from 'react'
import { throttle } from 'lodash'

class Foo extends React.Component {
  constructor(props) {
    super(props)
    this.resize = throttle(this.resize.bind(this), 100)
  }

  resize = () => this.forceUpdate()

  componentDidMount() {
    window.addEventListener('resize', this.resize)
  }

  componentWillUnmount() {
    window.removeEventListener('resize', this.resize)
  }

  render() {
    return (
      <div>{window.innerWidth} x {window.innerHeight}</div>
    )
  }
}

Another method is to just use a "dummy" state instead of forceUpdate:

import React from 'react'
import { throttle } from 'lodash'

class Foo extends React.Component {
  constructor(props) {
    super(props)
    this.state = { foo: 1 }
    this.resize = throttle(this.resize.bind(this), 100)
  }

  resize = () => this.setState({ foo: 1 })

  componentDidMount() {
    window.addEventListener('resize', this.resize)
  }

  componentWillUnmount() {
    window.removeEventListener('resize', this.resize)
  }

  render() {
    return (
      <div>{window.innerWidth} x {window.innerHeight}</div>
    )
  }
}

Android - Best and safe way to stop thread

This situation isn't in any way different from the standard Java. You can use the standard way to stop a thread:

class WorkerThread extends Thread {
    volatile boolean running = true;

    public void run() {
        // Do work...
        if (!running) return;
        //Continue doing the work
    }
}

The main idea is to check the value of the field from time to time. When you need to stop your thread, you set running to false. Also, as Chris has pointed out, you can use the interruption mechanism.

By the way, when you use AsyncTask, your apporach won't differ much. The only difference is that you will have to call isCancel() method from your task instead of having a special field. If you call cancel(true), but don't implement this mechanism, the thread still won't stop by itself, it will run to the end.

Trigger change event of dropdown

I don't know that much JQuery but I've heard it allows to fire native events with this syntax.

$(document).ready(function(){

    $('#countrylist').change(function(e){
       // Your event handler
    });

    // And now fire change event when the DOM is ready
    $('#countrylist').trigger('change');
});

You must declare the change event handler before calling trigger() or change() otherwise it won't be fired. Thanks for the mention @LenielMacaferi.

More information here.

async/await - when to return a Task vs void?

The problem with calling async void is that

you don’t even get the task back. You have no way of knowing when the function’s task has completed. —— Crash course in async and await | The Old New Thing

Here are the three ways to call an async function:

async Task<T> SomethingAsync() { ... return t; }
async Task SomethingAsync() { ... }
async void SomethingAsync() { ... }

In all the cases, the function is transformed into a chain of tasks. The difference is what the function returns.

In the first case, the function returns a task that eventually produces the t.

In the second case, the function returns a task which has no product, but you can still await on it to know when it has run to completion.

The third case is the nasty one. The third case is like the second case, except that you don't even get the task back. You have no way of knowing when the function's task has completed.

The async void case is a "fire and forget": You start the task chain, but you don't care about when it's finished. When the function returns, all you know is that everything up to the first await has executed. Everything after the first await will run at some unspecified point in the future that you have no access to.

Convert timestamp to date in Oracle SQL

If you have milliseconds in the date string, you can use the following.

select TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')From Dual;

And then convert it to Date with:

select trunc(TO_TIMESTAMP(SUBSTR('2020-09-10T09:37:28.378-07:00',1,23), 'YYYY-MM-DD"T"HH24:MI:SS:FF3')) From Dual;

It worked for me, hope it will help you as well.

How to change the Spyder editor background to dark?

In Spyder 4.1, you can change background color from: Tools > Preferences > Appearance > Syntax highlighting scheme

How do you search an amazon s3 bucket?

Not a technical answer, but I have built an application which allows for wildcard search: https://bucketsearch.net/

It will asynchronously index your bucket and then allow you to search the results.

It's free to use (donationware).

pandas dataframe convert column type to string or categorical

Prior answers focused on nominal data (e.g. unordered). If there is a reason to impose order for an ordinal variable, then one would use:

# Transform to category
df['zipcode_category'] = df['zipcode_category'].astype('category')

# Add ordered category
df['zipcode_ordered'] = df['zipcode_category']

# Setup the ordering
df.zipcode_ordered.cat.set_categories(
    new_categories = [90211, 90210], ordered = True, inplace = True
)

# Output IDs
df['zipcode_ordered_id'] = df.zipcode_ordered.cat.codes
print(df)
#  zipcode_category zipcode_ordered  zipcode_ordered_id
#            90210           90210                   1
#            90211           90211                   0

More details on setting ordered categories can be found at the pandas website:

https://pandas.pydata.org/pandas-docs/stable/user_guide/categorical.html#sorting-and-order

How to check the input is an integer or not in Java?

You can try this way

 String input = "";
 try {
   int x = Integer.parseInt(input); 
   // You can use this method to convert String to int, But if input 
   //is not an int  value then this will throws NumberFormatException. 
   System.out.println("Valid input");
 }catch(NumberFormatException e) {
   System.out.println("input is not an int value"); 
   // Here catch NumberFormatException
   // So input is not a int.
 } 

Maven error: Not authorized, ReasonPhrase:Unauthorized

The issue may happen while fetching dependencies from a remote repository. In my case, the repository did not need any authentication and it has been resolved by removing the servers section in the settings.xml file:

<servers>
    <server>
      <id>SomeRepo</id>
      <username>SomeUN</username>
      <password>SomePW</password>
    </server>
</servers>

ps: I guess your target is mvn clean install instead of maven install clean

How to remove items from a list while iterating?

The other answers are correct that it is usually a bad idea to delete from a list that you're iterating. Reverse iterating avoids the pitfalls, but it is much more difficult to follow code that does that, so usually you're better off using a list comprehension or filter.

There is, however, one case where it is safe to remove elements from a sequence that you are iterating: if you're only removing one item while you're iterating. This can be ensured using a return or a break. For example:

for i, item in enumerate(lst):
    if item % 4 == 0:
        foo(item)
        del lst[i]
        break

This is often easier to understand than a list comprehension when you're doing some operations with side effects on the first item in a list that meets some condition and then removing that item from the list immediately after.

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

A p tag is for a paragraph, generally used for text. A div tag is for division, and generally used for creating sections of text.

How can I get an HTTP response body as a string?

We can use the below code also to get the HTML Response in java

import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.HttpResponse;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import org.apache.log4j.Logger;

public static void main(String[] args) throws Exception {
    HttpClient client = new DefaultHttpClient();
    //  args[0] :-  http://hostname:8080/abc/xyz/CheckResponse
    HttpGet request1 = new HttpGet(args[0]);
    HttpResponse response1 = client.execute(request1);
    int code = response1.getStatusLine().getStatusCode();

    try (BufferedReader br = new BufferedReader(new InputStreamReader((response1.getEntity().getContent())));) {
        // Read in all of the post results into a String.
        String output = "";
        Boolean keepGoing = true;
        while (keepGoing) {
            String currentLine = br.readLine();

            if (currentLine == null) {
                keepGoing = false;
            } else {
                output += currentLine;
            }
        }

        System.out.println("Response-->" + output);
    } catch (Exception e) {
        System.out.println("Exception" + e);

    }
}

"ssl module in Python is not available" when installing package with pip3

On macos, configure python 3.8.1 with the command below will solve the problem, i think it would also work on Linux.

./configure --enable-optimizations --with-openssl=/usr/local/opt/[email protected]/

change the dir parameter based on your system.

XCOPY switch to create specified directory if it doesn't exist?

Simple short answer is this:

xcopy /Y /I "$(SolutionDir)<my-src-path>" "$(SolutionDir)<my-dst-path>\"

Byte Array to Image object

According to the Java docs, it looks like you need to use the MemoryImageSource Class to put your byte array into an object in memory, and then use Component.createImage(ImageProducer) next (passing in your MemoryImageSource, which implements ImageProducer).

How to get the current TimeStamp?

In Qt 4.7, there is the QDateTime::currentMSecsSinceEpoch() static function, which does exactly what you need, without any intermediary steps. Hence I'd recommend that for projects using Qt 4.7 or newer.

MySQL DAYOFWEEK() - my week begins with monday

You can easily use the MODE argument:

MySQL :: MySQL 5.5 Reference Manual :: 12.7 Date and Time Functions

If the mode argument is omitted, the value of the default_week_format system variable is used:

MySQL :: MySQL 5.1 Reference Manual :: 5.1.4 Server System Variables

HTML embedded PDF iframe

It's downloaded probably because there is not Adobe Reader plug-in installed. In this case, IE (it doesn't matter which version) doesn't know how to render it, and it'll simply download the file (Chrome, for example, has its own embedded PDF renderer).

That said. <iframe> is not best way to display a PDF (do not forget compatibility with mobile browsers, for example Safari). Some browsers will always open that file inside an external application (or in another browser window). Best and most compatible way I found is a little bit tricky but works on all browsers I tried (even pretty outdated):

Keep your <iframe> but do not display a PDF inside it, it'll be filled with an HTML page that consists of an <object> tag. Create an HTML wrapping page for your PDF, it should look like this:

<html>
<body>
    <object data="your_url_to_pdf" type="application/pdf">
        <embed src="your_url_to_pdf" type="application/pdf" />
    </object>
</body>
</html>

Of course, you still need the appropriate plug-in installed in the browser. Also, look at this post if you need to support Safari on mobile devices.

1st. Why nesting <embed> inside <object>? You'll find the answer here on SO. Instead of a nested <embed> tag, you may (should!) provide a custom message for your users (or a built-in viewer, see next paragraph). Nowadays, <object> can be used without worries, and <embed> is useless.

2nd. Why an HTML page? So you can provide a fallback if PDF viewer isn't supported. Internal viewer, plain HTML error messages/options, and so on...

It's tricky to check PDF support so that you may provide an alternate viewer for your customers, take a look at PDF.JS project; it's pretty good but rendering quality - for desktop browsers - isn't as good as a native PDF renderer (I didn't see any difference in mobile browsers because of screen size, I suppose).

MySQL and PHP - insert NULL rather than empty string

This works just fine for me:

INSERT INTO table VALUES ('', NULLIF('$date',''))

(first '' increments id field)

Android WebView Cookie Problem

Thanks Android for ruining my Sunday . . . Heres what fixed my Apps ( after you init your webview )

if ( Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP ) {

  CookieManager cookieManager = CookieManager.getInstance();

  cookieManager.setAcceptThirdPartyCookies( webView, true );

}

I should say the above answers will probably work but in my situation the moment Android went v5+ my android webview javascript 'apps' died.

how to write value into cell with vba code without auto type conversion?

This is probably too late, but I had a similar problem with dates that I wanted entered into cells from a text variable. Inevitably, it converted my variable text value to a date. What I finally had to do was concatentate a ' to the string variable and then put it in the cell like this:

prvt_rng_WrkSht.Cells(prvt_rng_WrkSht.Rows.Count, cnst_int_Col_Start_Date).Formula = "'" & _ 
    param_cls_shift.Start_Date (string property of my class) 

How to add fixed button to the bottom right of page

This will be helpful for the right bottom rounded button

HTML :

      <a class="fixedButton" href>
         <div class="roundedFixedBtn"><i class="fa fa-phone"></i></div>
      </a>
    

CSS:

       .fixedButton{
            position: fixed;
            bottom: 0px;
            right: 0px; 
            padding: 20px;
        }
        .roundedFixedBtn{
          height: 60px;
          line-height: 80px;  
          width: 60px;  
          font-size: 2em;
          font-weight: bold;
          border-radius: 50%;
          background-color: #4CAF50;
          color: white;
          text-align: center;
          cursor: pointer;
        }
    

Here is jsfiddle link http://jsfiddle.net/vpthcsx8/11/

What's the maximum value for an int in PHP?

(a little bit late, but could be useful)

Only trust PHP_INT_MAX and PHP_INT_SIZE, this value vary on your arch (32/64 bits) and your OS...

Any other "guess" or "hint" can be false.

Is there any sizeof-like method in Java?

From the article in JavaWorld

A superficial answer is that Java does not provide anything like C's sizeof(). However, let's consider why a Java programmer might occasionally want it.

A C programmer manages most datastructure memory allocations himself, and sizeof() is indispensable for knowing memory block sizes to allocate. Additionally, C memory allocators like malloc() do almost nothing as far as object initialization is concerned: a programmer must set all object fields that are pointers to further objects. But when all is said and coded, C/C++ memory allocation is quite efficient.

By comparison, Java object allocation and construction are tied together (it is impossible to use an allocated but uninitialized object instance). If a Java class defines fields that are references to further objects, it is also common to set them at construction time. Allocating a Java object therefore frequently allocates numerous interconnected object instances: an object graph. Coupled with automatic garbage collection, this is all too convenient and can make you feel like you never have to worry about Java memory allocation details.

Of course, this works only for simple Java applications. Compared with C/C++, equivalent Java datastructures tend to occupy more physical memory. In enterprise software development, getting close to the maximum available virtual memory on today's 32-bit JVMs is a common scalability constraint. Thus, a Java programmer could benefit from sizeof() or something similar to keep an eye on whether his datastructures are getting too large or contain memory bottlenecks. Fortunately, Java reflection allows you to write such a tool quite easily.

Before proceeding, I will dispense with some frequent but incorrect answers to this article's question. Fallacy: Sizeof() is not needed because Java basic types' sizes are fixed

Yes, a Java int is 32 bits in all JVMs and on all platforms, but this is only a language specification requirement for the programmer-perceivable width of this data type. Such an int is essentially an abstract data type and can be backed up by, say, a 64-bit physical memory word on a 64-bit machine. The same goes for nonprimitive types: the Java language specification says nothing about how class fields should be aligned in physical memory or that an array of booleans couldn't be implemented as a compact bitvector inside the JVM. Fallacy: You can measure an object's size by serializing it into a byte stream and looking at the resulting stream length

The reason this does not work is because the serialization layout is only a remote reflection of the true in-memory layout. One easy way to see it is by looking at how Strings get serialized: in memory every char is at least 2 bytes, but in serialized form Strings are UTF-8 encoded and so any ASCII content takes half as much space

Why is datetime.strptime not working in this simple example?

If in the folder with your project you created a file with the name "datetime.py"

NoClassDefFoundError while trying to run my jar with java.exe -jar...what's wrong?

The -jar option is mutually exclusive of -classpath. See an old description here

-jar

Execute a program encapsulated in a JAR file. The first argument is the name of a JAR file instead of a startup class name. In order for this option to work, the manifest of the JAR file must contain a line of the form Main-Class: classname. Here, classname identifies the class having the public static void main(String[] args) method that serves as your application's starting point.

See the Jar tool reference page and the Jar trail of the Java Tutorial for information about working with Jar files and Jar-file manifests.

When you use this option, the JAR file is the source of all user classes, and other user class path settings are ignored.

A quick and dirty hack is to append your classpath to the bootstrap classpath:

-Xbootclasspath/a:path

Specify a colon-separated path of directires, JAR archives, and ZIP archives to append to the default bootstrap class path.

However, as @Dan rightly says, the correct solution is to ensure your JARs Manifest contains the classpath for all JARs it will need.

Add left/right horizontal padding to UILabel

Swift 5

Create below class file and set it to your label as custom class name through storyboard. That's it.

class PaddingLabel: UILabel {

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets(top: 0, left: 8, bottom: 0, right: 0)//CGRect.inset(by:)
        super.drawText(in: rect.inset(by: insets))
    }
}

How do you check if a variable is an array in JavaScript?

Since the .length property is special for arrays in javascript you can simply say

obj.length === +obj.length // true if obj is an array

Underscorejs and several other libraries use this short and simple trick.

iOS 7: UITableView shows under status bar

Abrahamchez's solution https://developer.apple.com/library/ios/qa/qa1797/_index.html worked for me as follows. I had a single UITableviewcontroller as my initial view. I had tried the offset code and embedding in a navcon but neither solved the statusbar transparency.

Add a Viewcontroller and make it the initial view. This should show you critical Top & Bottom Layout Guides.

Drag the old Tableview into the View in the new controller.

Do all the stuff to retrofit the table into the new controller:

Change your old view controller.h file to inherit/subclass from UIViewController instead of UITableViewController.

Add UITableViewDataSource and UITableViewDelegate to the viewcontroller's .h.

Re-connect anything needed in the storyboard, such as a Searchbar.

The big thing is to get the constraints set up, as in the Apple Q&A. I didn't bother inserting a toolbar. Not certain the exact sequence. But a red icon appeared on the Layout Guides, perhaps when I built. I clicked it and let Xcode install/clean up the constraints.

Then I clicked everywhere until I found the Vertical Space constraint and changed its top value from -20 to 0 and it worked perfectly.

How do I position an image at the bottom of div?

Add relative positioning to the wrapping div tag, then absolutely position the image within it like this:

CSS:

.div-wrapper {
    position: relative;
    height: 300px;
    width: 300px;
}

.div-wrapper img {
    position: absolute;
    left: 0;
    bottom: 0;
}

HTML:

<div class="div-wrapper">
    <img src="blah.png"/>
</div>

Now the image sits at the bottom of the div.

Is using 'var' to declare variables optional?

There's so much confusion around this subject, and none of the existing answers cover everything clearly and directly. Here are some examples with comments inline.

//this is a declaration
var foo;

//this is an assignment
bar = 3;

//this is a declaration and an assignment
var dual = 5;

A declaration sets a DontDelete flag. An assignment does not.

A declaration ties that variable to the current scope.

A variable assigned but not declared will look for a scope to attach itself to. That means it will traverse up the food-chain of scope until a variable with the same name is found. If none is found, it will be attached to the top-level scope (which is commonly referred to as global).

function example(){
  //is a member of the scope defined by the function example
  var foo;

  //this function is also part of the scope of the function example
  var bar = function(){
     foo = 12; // traverses scope and assigns example.foo to 12
  }
}

function something_different(){
     foo = 15; // traverses scope and assigns global.foo to 15
}

For a very clear description of what is happening, this analysis of the delete function covers variable instantiation and assignment extensively.

How can I output the value of an enum class in C++11

(I'm not allowed to comment yet.) I would suggest the following improvements to the already great answer of James McNellis:

template <typename Enumeration>
constexpr auto as_integer(Enumeration const value)
    -> typename std::underlying_type<Enumeration>::type
{
    static_assert(std::is_enum<Enumeration>::value, "parameter is not of type enum or enum class");
    return static_cast<typename std::underlying_type<Enumeration>::type>(value);
}

with

  • constexpr: allowing me to use an enum member value as compile-time array size
  • static_assert+is_enum: to 'ensure' compile-time that the function does sth. with enumerations only, as suggested

By the way I'm asking myself: Why should I ever use enum class when I would like to assign number values to my enum members?! Considering the conversion effort.

Perhaps I would then go back to ordinary enum as I suggested here: How to use enums as flags in C++?


Yet another (better) flavor of it without static_assert, based on a suggestion of @TobySpeight:

template <typename Enumeration>
constexpr std::enable_if_t<std::is_enum<Enumeration>::value,
std::underlying_type_t<Enumeration>> as_number(const Enumeration value)
{
    return static_cast<std::underlying_type_t<Enumeration>>(value);
}

Is there a "not equal" operator in Python?

You can use "is not" for "not equal" or "!=". Please see the example below:

a = 2
if a == 2:
   print("true")
else:
   print("false")

The above code will print "true" as a = 2 assigned before the "if" condition. Now please see the code below for "not equal"

a = 2
if a is not 3:
   print("not equal")
else:
   print("equal")

The above code will print "not equal" as a = 2 as assigned earlier.

Fastest way to find second (third...) highest/lowest value in vector or column

You can use the sort keyword like this:

sort(unique(c))[1:N]

Example:

c <- c(4,2,44,2,1,45,34,2,4,22,244)
sort(unique(c), decreasing = TRUE)[1:5]

will give the first 5 max numbers.

Word count from a txt file program

Below code from Python | How to Count the frequency of a word in the text file? worked for me.

 import re
    frequency = {}
    #Open the sample text file in read mode.
    document_text = open('sample.txt', 'r')
    #convert the string of the document in lowercase and assign it to text_string variable.
    text = document_text.read().lower()
    pattern = re.findall(r'\b[a-z]{2,15}\b', text)
    for word in pattern:
         count = frequency.get(word,0)
         frequency[word] = count + 1
     frequency_list = frequency.keys()
     for words in frequency_list:
         print(words, frequency[words])

OUTPUT: enter image description here

how to drop database in sqlite?

SQLite database FAQ: How do I drop a SQLite database?

People used to working with other databases are used to having a "drop database" command, but in SQLite there is no similar command. The reason? In SQLite there is no "database server" -- SQLite is an embedded database, and your database is entirely contained in one file. So there is no need for a SQLite drop database command.

To "drop" a SQLite database, all you have to do is delete the SQLite database file you were accessing.

copy from http://alvinalexander.com/android/sqlite-drop-database-how

Connect Android Studio with SVN

Go to File->Settings->Version Control->Subversion enter the path for your SVN executable in the General tab under Subversion configuration directory. Also, you can download a latest SVN client such as VisualSVN and point the path to the executable as mentioned above. That will most likely solve your problem.

c++ string array initialization

In C++11 you can. A note beforehand: Don't new the array, there's no need for that.

First, string[] strArray is a syntax error, that should either be string* strArray or string strArray[]. And I assume that it's just for the sake of the example that you don't pass any size parameter.

#include <string>

void foo(std::string* strArray, unsigned size){
  // do stuff...
}

template<class T>
using alias = T;

int main(){
  foo(alias<std::string[]>{"hi", "there"}, 2);
}

Note that it would be better if you didn't need to pass the array size as an extra parameter, and thankfully there is a way: Templates!

template<unsigned N>
void foo(int const (&arr)[N]){
  // ...
}

Note that this will only match stack arrays, like int x[5] = .... Or temporary ones, created by the use of alias above.

int main(){
  foo(alias<int[]>{1, 2, 3});
}

Django error - matching query does not exist

Maybe you have no Comments record with such primary key, then you should use this code:

try:
    comment = Comment.objects.get(pk=comment_id)
except Comment.DoesNotExist:
    comment = None

How do I split an int into its digits?

#include <iostream>

using namespace std;

int main()

{


int n1 ;

cout <<"Please enter five digits number: ";
cin >> n1;

    cout << n1 / 10000 % 10 << " ";
    cout << n1 / 1000 % 10 << " ";
    cout << n1 / 100 % 10 << " ";
    cout << n1 / 10 % 10 << " ";
    cout << n1 % 10 << " :)";   

cout << endl;

return 0;
}

How to blur background images in Android

This is an easy way to blur Images Efficiently with Android's RenderScript that I found on this article

  1. Create a Class called BlurBuilder

    public class BlurBuilder {
      private static final float BITMAP_SCALE = 0.4f;
      private static final float BLUR_RADIUS = 7.5f;
    
      public static Bitmap blur(Context context, Bitmap image) {
        int width = Math.round(image.getWidth() * BITMAP_SCALE);
        int height = Math.round(image.getHeight() * BITMAP_SCALE);
    
        Bitmap inputBitmap = Bitmap.createScaledBitmap(image, width, height, false);
        Bitmap outputBitmap = Bitmap.createBitmap(inputBitmap);
    
        RenderScript rs = RenderScript.create(context);
        ScriptIntrinsicBlur theIntrinsic = ScriptIntrinsicBlur.create(rs, Element.U8_4(rs));
        Allocation tmpIn = Allocation.createFromBitmap(rs, inputBitmap);
        Allocation tmpOut = Allocation.createFromBitmap(rs, outputBitmap);
        theIntrinsic.setRadius(BLUR_RADIUS);
        theIntrinsic.setInput(tmpIn);
        theIntrinsic.forEach(tmpOut);
        tmpOut.copyTo(outputBitmap);
    
        return outputBitmap;
      }
    }
    
  2. Copy any image to your drawable folder

  3. Use BlurBuilder in your activity like this:

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                WindowManager.LayoutParams.FLAG_FULLSCREEN);
        setContentView(R.layout.activity_login);
    
        mContainerView = (LinearLayout) findViewById(R.id.container);
        Bitmap originalBitmap = BitmapFactory.decodeResource(getResources(), R.drawable.background);
        Bitmap blurredBitmap = BlurBuilder.blur( this, originalBitmap );
        mContainerView.setBackground(new BitmapDrawable(getResources(), blurredBitmap));
    
  4. Renderscript is included into support v8 enabling this answer down to api 8. To enable it using gradle include these lines into your gradle file (from this answer)

    defaultConfig {
        ...
        renderscriptTargetApi *your target api*
        renderscriptSupportModeEnabled true
    }
    
  5. Result

enter image description here

How can I write data in YAML format in a file?

Link to the PyYAML documentation showing the difference for the default_flow_style parameter. To write it to a file in block mode (often more readable):

d = {'A':'a', 'B':{'C':'c', 'D':'d', 'E':'e'}}
with open('result.yml', 'w') as yaml_file:
    yaml.dump(d, yaml_file, default_flow_style=False)

produces:

A: a
B:
  C: c
  D: d
  E: e

What is the best way to check for Internet connectivity using .NET?

Does not solve the problem of network going down between checking and running your code but is fairly reliable

public static bool IsAvailableNetworkActive()
{
    // only recognizes changes related to Internet adapters
    if (System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable())
    {
        // however, this will include all adapters -- filter by opstatus and activity
        NetworkInterface[] interfaces = System.Net.NetworkInformation.NetworkInterface.GetAllNetworkInterfaces();
        return (from face in interfaces
                where face.OperationalStatus == OperationalStatus.Up
                where (face.NetworkInterfaceType != NetworkInterfaceType.Tunnel) && (face.NetworkInterfaceType != NetworkInterfaceType.Loopback)
                select face.GetIPv4Statistics()).Any(statistics => (statistics.BytesReceived > 0) && (statistics.BytesSent > 0));
    }

    return false;
}

Can someone give an example of cosine similarity, in a very simple, graphical way?

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

/**
 * 
* @author Xiao Ma
* mail : [email protected]
*
*/
  public class SimilarityUtil {

public static double consineTextSimilarity(String[] left, String[] right) {
    Map<String, Integer> leftWordCountMap = new HashMap<String, Integer>();
    Map<String, Integer> rightWordCountMap = new HashMap<String, Integer>();
    Set<String> uniqueSet = new HashSet<String>();
    Integer temp = null;
    for (String leftWord : left) {
        temp = leftWordCountMap.get(leftWord);
        if (temp == null) {
            leftWordCountMap.put(leftWord, 1);
            uniqueSet.add(leftWord);
        } else {
            leftWordCountMap.put(leftWord, temp + 1);
        }
    }
    for (String rightWord : right) {
        temp = rightWordCountMap.get(rightWord);
        if (temp == null) {
            rightWordCountMap.put(rightWord, 1);
            uniqueSet.add(rightWord);
        } else {
            rightWordCountMap.put(rightWord, temp + 1);
        }
    }
    int[] leftVector = new int[uniqueSet.size()];
    int[] rightVector = new int[uniqueSet.size()];
    int index = 0;
    Integer tempCount = 0;
    for (String uniqueWord : uniqueSet) {
        tempCount = leftWordCountMap.get(uniqueWord);
        leftVector[index] = tempCount == null ? 0 : tempCount;
        tempCount = rightWordCountMap.get(uniqueWord);
        rightVector[index] = tempCount == null ? 0 : tempCount;
        index++;
    }
    return consineVectorSimilarity(leftVector, rightVector);
}

/**
 * The resulting similarity ranges from -1 meaning exactly opposite, to 1
 * meaning exactly the same, with 0 usually indicating independence, and
 * in-between values indicating intermediate similarity or dissimilarity.
 * 
 * For text matching, the attribute vectors A and B are usually the term
 * frequency vectors of the documents. The cosine similarity can be seen as
 * a method of normalizing document length during comparison.
 * 
 * In the case of information retrieval, the cosine similarity of two
 * documents will range from 0 to 1, since the term frequencies (tf-idf
 * weights) cannot be negative. The angle between two term frequency vectors
 * cannot be greater than 90°.
 * 
 * @param leftVector
 * @param rightVector
 * @return
 */
private static double consineVectorSimilarity(int[] leftVector,
        int[] rightVector) {
    if (leftVector.length != rightVector.length)
        return 1;
    double dotProduct = 0;
    double leftNorm = 0;
    double rightNorm = 0;
    for (int i = 0; i < leftVector.length; i++) {
        dotProduct += leftVector[i] * rightVector[i];
        leftNorm += leftVector[i] * leftVector[i];
        rightNorm += rightVector[i] * rightVector[i];
    }

    double result = dotProduct
            / (Math.sqrt(leftNorm) * Math.sqrt(rightNorm));
    return result;
}

public static void main(String[] args) {
    String left[] = { "Julie", "loves", "me", "more", "than", "Linda",
            "loves", "me" };
    String right[] = { "Jane", "likes", "me", "more", "than", "Julie",
            "loves", "me" };
    System.out.println(consineTextSimilarity(left,right));
}
}

SQL Server: use CASE with LIKE

SELECT Lname, Cods, CASE WHEN Lname LIKE '% HN%' THEN SUBSTRING(Lname, 
CHARINDEX(' ', Lname) - 50, 50) WHEN Lname LIKE 'HN%' THEN Lname ELSE 
Lname END AS LnameTrue FROM dbo.____Fname_Lname

How to get the text node of an element?

You can get the nodeValue of the first childNode using

$('.title')[0].childNodes[0].nodeValue

http://jsfiddle.net/TU4FB/

Create a shortcut on Desktop

I use "Windows Script Host Object Model" reference to create shortcut.

Adding "Windows Script Host Object Model" to project references

and to create shortcut on specific location:

    void CreateShortcut(string linkPath, string filename)
    {
        // Create shortcut dir if not exists
        if (!Directory.Exists(linkPath))
            Directory.CreateDirectory(linkPath);

        // shortcut file name
        string linkName = Path.ChangeExtension(Path.GetFileName(filename), ".lnk");

        // COM object instance/props
        IWshRuntimeLibrary.WshShell shell = new IWshRuntimeLibrary.WshShell();
        IWshRuntimeLibrary.IWshShortcut sc = (IWshRuntimeLibrary.IWshShortcut)shell.CreateShortcut(linkName);
        sc.Description = "some desc";
        //shortcut.IconLocation = @"C:\..."; 
        sc.TargetPath = linkPath;
        // save shortcut to target
        sc.Save();
    }

How do I create a new class in IntelliJ without using the mouse?

If you are already in the Project View, press Alt+Insert (New) | Class. Project View can be activated via Alt+1.

To create a new class in the same directory as the current one use Ctrl+Alt+Insert (New...).

You can also do it from the Navigation Bar, press Alt+Home, then choose package with arrow keys, then press Alt+Insert.

Another useful shortcut is View | Select In (Alt+F1), Project (1), then Alt+Insert to create a class near the existing one or use arrow keys to navigate through the packages.

And yet another way is to just type the class name in the existing code where you want to use it, IDEA will highlight it in red as it doesn't exist yet, then press Alt+Enter for the Intention Actions pop-up, choose Create Class.

Using ListView : How to add a header view?

You simply can't use View as a Header of ListView.

Because the view which is being passed in has to be inflated.

Look at my answer at Android ListView addHeaderView() nullPointerException for predefined Views for more info.

EDIT:

Look at this tutorial Android ListView and ListActivity - Tutorial .

EDIT 2: This link is broken Android ListActivity with a header or footer

Could not load file or assembly '***.dll' or one of its dependencies

I ran into this recently. It turned out that the old DLL was compiled with a previous version (Visual Studio 2008) and was referencing that version of the dynamic runtime libraries. I was trying to run it on a system that only had .NET 4.0 on it and I'd never installed any dynamic runtime libraries. The solution? I recompiled the DLL to link the static runtime libraries.

Check your application error log in Event Viewer (EVENTVWR.EXE). It will give you more information on the error and will probably point you at the real cause of the problem.

Link to "pin it" on pinterest without generating a button

The standard Pinterest button code (which you can generate here), is an <a> tag wrapping an <img> of the Pinterest button.

If you don't include the pinit.js script on your page, this <a> tag will work "as-is". You could improve the experience by registering your own click handler on these tags that opens a new window with appropriate dimensions, or at least adding target="_blank" to the tag to make it open clicks in a new window.

The tag syntax would look like:

<a href="http://pinterest.com/pin/create/button/?url={URI-encoded URL of the page to pin}&media={URI-encoded URL of the image to pin}&description={optional URI-encoded description}" class="pin-it-button" count-layout="horizontal">
    <img border="0" src="//assets.pinterest.com/images/PinExt.png" title="Pin It" />
</a>

If using the JavaScript versions of sharing buttons are ruining your page load times, you can improve your site by using asynchronous loading methods. For an example of doing this with the Pinterest button, check out my GitHub Pinterest button project with an improved HTML5 syntax.

How do I get a Date without time in Java?

Is there any other way than these two?

Yes, there is.

LocalDate.now( 
    ZoneId.of( "Pacific/Auckland" ) 
)

java.time

Java 8 and later comes with the new java.time package built-in. See Tutorial. Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport and further adapted to Android in ThreeTenABP.

Similar to Joda-Time, java.time offers a LocalDate class to represent a date-only value without time-of-day and without time zone.

Note that time zone is critical to determining a particular date. At the stroke of midnight in Paris, for example, the date is still “yesterday” in Montréal.

LocalDate today = LocalDate.now( ZoneId.of( "America/Montreal" ) ) ;

By default, java.time uses the ISO 8601 standard in generating a string representation of a date or date-time value. (Another similarity with Joda-Time.) So simply call toString() to generate text like 2015-05-21.

String output = today.toString() ; 

About java.time

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

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

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

Where to obtain the java.time classes?

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

JavaScript hide/show element

_x000D_
_x000D_
function showStuff(id, text, btn) {_x000D_
    document.getElementById(id).style.display = 'block';_x000D_
    // hide the lorem ipsum text_x000D_
    document.getElementById(text).style.display = 'none';_x000D_
    // hide the link_x000D_
    btn.style.display = 'none';_x000D_
}
_x000D_
<td class="post">_x000D_
_x000D_
<a href="#" onclick="showStuff('answer1', 'text1', this); return false;">Edit</a>_x000D_
<span id="answer1" style="display: none;">_x000D_
<textarea rows="10" cols="115"></textarea>_x000D_
</span>_x000D_
_x000D_
<span id="text1">Lorem ipsum Lorem ipsum Lorem ipsum Lorem ipsum</span>_x000D_
</td>
_x000D_
_x000D_
_x000D_

Parse HTML table to Python list?

Hands down the easiest way to parse a HTML table is to use pandas.read_html() - it accepts both URLs and HTML.

import pandas as pd
url = r'https://en.wikipedia.org/wiki/List_of_S%26P_500_companies'
tables = pd.read_html(url) # Returns list of all tables on page
sp500_table = tables[0] # Select table of interest

Only downside is that read_html() doesn't preserve hyperlinks.

How do I check if a column is empty or null in MySQL?

You can test whether a column is null or is not null using WHERE col IS NULL or WHERE col IS NOT NULL e.g.

SELECT myCol 
FROM MyTable 
WHERE MyCol IS NULL 

In your example you have various permutations of white space. You can strip white space using TRIM and you can use COALESCE to default a NULL value (COALESCE will return the first non-null value from the values you suppy.

e.g.

SELECT myCol
FROM MyTable
WHERE TRIM(COALESCE(MyCol, '')) = '' 

This final query will return rows where MyCol is null or is any length of whitespace.

If you can avoid it, it's better not to have a function on a column in the WHERE clause as it makes it difficult to use an index. If you simply want to check if a column is null or empty, you may be better off doing this:

SELECT myCol
FROM MyTable
WHERE MyCol IS NULL OR MyCol =  '' 

See TRIM COALESCE and IS NULL for more info.

Also Working with null values from the MySQL docs

dispatch_after - GCD in Swift?

Now more than syntactic sugar for asynchronous dispatches in Grand Central Dispatch (GCD) in Swift.

add Podfile

pod 'AsyncSwift'

Then,you can use it like this.

let seconds = 3.0
Async.main(after: seconds) {
print("Is called after 3 seconds")
}.background(after: 6.0) {
print("At least 3.0 seconds after previous block, and 6.0 after Async code is called")
}

How to store Emoji Character in MySQL Database

If you use command line interface for inserting sql file to database.

Be sure your table charset utf8mb4 and column collation utf8mb4_unicode_ci or utf8mb4_bin

mysql -u root -p123456 my_database < profiles.sql

ERROR 1366 (HY000) at line 1679: Incorrect string value: '\xF0\x9F\x98\x87\xF0\x9F...' for column 'note' at row 328

we can solve the problem with this parameter --default-character-set=name (Set the default character set)

mysql -u root -p123456 --default-character-set=utf8mb4 my_database < profiles.sql

How to truncate text in Angular2?

Very simple using slice pipe (angular's core pipe), as you asked for data.title:

{{ data.title | slice:0:20 }}

From Angular common docs https://angular.io/api/common/SlicePipe

HTML form submit to PHP script

Try this:

<form method="post" action="check.php">
    <select name="website_string">
        <option value="" selected="selected"></option>
        <option VALUE="abc"> ABC</option>
        <option VALUE="def"> def</option>
        <option VALUE="hij"> hij</option>
    </select>
    <input TYPE="submit" name="submit" />
</form>

Both your select control and your submit button had the same name attribute, so the last one used was the submit button when you clicked it. All other syntax errors aside.

check.php

<?php
    echo $_POST['website_string'];
?>

Obligatory disclaimer about using raw $_POST data. Sanitize anything you'll actually be using in application logic.

client denied by server configuration

in my case,

i'm using macOS Mojave (Apache/2.4.34). There was an issue in virtual host settings at /etc/apache2/extra/httpd-vhosts.conf file. after adding the required directory tag my problem was gone.

Require all granted

Hope the full virtual host setup structure will save you.

<VirtualHost *:80>
    DocumentRoot "/Users/vagabond/Sites/MainProjectFolderName/public/"
    ServerName project.loc

    <Directory /Users/vagabond/Sites/MainProjectFolderName/public/>
        Require all granted
    </Directory>

    ErrorLog "/Users/vagabond/Sites/logs/MainProjectFolderName.loc-error_log"
    CustomLog "/Users/vagabond/Sites/logs/MainProjectFolderName.loc-access_log" common
</VirtualHost>

all you've to do replace the MainProjectFolderName with your exact ProjectFolderName.

How do I send email with JavaScript without opening the mail client?

You can't do it with client side script only... you could make an AJAX call to some server side code that will send an email...

Difference between a Seq and a List in Scala

In Scala, a List inherits from Seq, but implements Product; here is the proper definition of List :

sealed abstract class List[+A] extends AbstractSeq[A] with Product with ...

[Note: the actual definition is a tad bit more complex, in order to fit in with and make use of Scala's very powerful collection framework.]

CSS :selected pseudo class similar to :checked, but for <select> elements

the :checked pseudo-class initially applies to such elements that have the HTML4 selected and checked attributes

Source: w3.org


So, this CSS works, although styling the color is not possible in every browser:

option:checked { color: red; }

An example of this in action, hiding the currently selected item from the drop down list.

_x000D_
_x000D_
option:checked { display:none; }
_x000D_
<select>_x000D_
    <option>A</option>_x000D_
    <option>B</option>_x000D_
    <option>C</option>_x000D_
</select>
_x000D_
_x000D_
_x000D_


To style the currently selected option in the closed dropdown as well, you could try reversing the logic:

select { color: red; }
option:not(:checked) { color: black; } /* or whatever your default style is */

ToList()-- does it create a new list?

From the Reflector'd source:

public static List<TSource> ToList<TSource>(this IEnumerable<TSource> source)
{
    if (source == null)
    {
        throw Error.ArgumentNull("source");
    }
    return new List<TSource>(source);
}

So yes, your original list won't be updated (i.e. additions or removals) however the referenced objects will.

"Large data" workflows using pandas

At the moment I am working "like" you, just on a lower scale, which is why I don't have a PoC for my suggestion.

However, I seem to find success in using pickle as caching system and outsourcing execution of various functions into files - executing these files from my commando / main file; For example i use a prepare_use.py to convert object types, split a data set into test, validating and prediction data set.

How does your caching with pickle work? I use strings in order to access pickle-files that are dynamically created, depending on which parameters and data sets were passed (with that i try to capture and determine if the program was already run, using .shape for data set, dict for passed parameters). Respecting these measures, i get a String to try to find and read a .pickle-file and can, if found, skip processing time in order to jump to the execution i am working on right now.

Using databases I encountered similar problems, which is why i found joy in using this solution, however - there are many constraints for sure - for example storing huge pickle sets due to redundancy. Updating a table from before to after a transformation can be done with proper indexing - validating information opens up a whole other book (I tried consolidating crawled rent data and stopped using a database after 2 hours basically - as I would have liked to jump back after every transformation process)

I hope my 2 cents help you in some way.

Greetings.

How to set selectedIndex of select element using display text?

<script type="text/javascript">
     function SelectAnimal(){
         //Set selected option of Animals based on AnimalToFind value...
         var animalTofind = document.getElementById('AnimalToFind');
         var selection = document.getElementById('Animals');

        // select element
        for(var i=0;i<selection.options.length;i++){
            if (selection.options[i].innerHTML == animalTofind.value) {
                selection.selectedIndex = i;
                break;
            }
        }
     }
</script>

setting the selectedIndex property of the select tag will choose the correct item. it is a good idea of instead of comparing the two values (options innerHTML && animal value) you can use the indexOf() method or regular expression to select the correct option despite casing or presense of spaces

selection.options[i].innerHTML.indexOf(animalTofind.value) != -1;

or using .match(/regular expression/)

Best way to access a control on another form in Windows Forms?

After reading the additional details, I agree with robcthegeek: raise an event. Create a custom EventArgs and pass the neccessary parameters through it.

How to check if a particular service is running on Ubuntu

run

ps -ef | grep name-related-to-process

above command will give all the details like pid, start time about the process.

like if you want all java realted process give java or if you have name of process place the name

Adjust width and height of iframe to fit with content in it

<iframe src="..." style="border:none; width:100%; height: 100vh;"></iframe>

What are the differences between C, C# and C++ in terms of real-world applications?

My opinion is C# and ASP.NET would be the best of the three for development that is web biased.

I doubt anyone writes new web apps in C or C++ anymore. It was done 10 years ago, and there's likely a lot of legacy code still in use, but they're not particularly well suited, there doesn't appear to be as much (ongoing) tool support, and they probably have a small active community that does web development (except perhaps for web server development). I wrote many website C++ COM objects back in the day, but C# is far more productive that there's no compelling reason to code C or C++ (in this context) unless you need to.

I do still write C++ if necessary, but it's typically for a small problem domain. e.g. communicating from C# via P/Invoke to old C-style dll's - doing some things that are downright clumsy in C# were a breeze to create a C++ COM object as a bridge.

The nice thing with C# is that you can also easily transfer into writing Windows and Console apps and stay in C#. With Mono you're also not limited to Windows (although you may be limited to which libraries you use).

Anyways this is all from a web-biased perspective. If you asked about embedded devices I'd say C or C++. You could argue none of these are suited for web development, but C#/ASP.NET is pretty slick, it works well, there are heaps of online resources, a huge community, and free dev tools.

So from a real-world perspective, picking only one of C#, C++ and C as requested, as a general rule, you're better to stick with C#.

Find a value in an array of objects in Javascript

Similar to previous answers I used the following:

    Array.prototype.getIemtByParam = function(paramPair) {
      var key = Object.keys(paramPair)[0];
      return this.find(function(item){return ((item[key] == paramPair[key]) ? true: false)});
    }

usage:

myArray.getIemtByParam(
    {name: 'Sasha'}
);

PHP - iterate on string characters

If your strings are in Unicode you should use preg_split with /u modifier

From comments in php documentation:

function mb_str_split( $string ) { 
    # Split at all position not after the start: ^ 
    # and not before the end: $ 
    return preg_split('/(?<!^)(?!$)/u', $string ); 
} 

Classes vs. Functions

Before answering your question:

If you do not have a Person class, first you must consider whether you want to create a Person class. Do you plan to reuse the concept of a Person very often? If so, you should create a Person class. (You have access to this data in the form of a passed-in variable and you don't care about being messy and sloppy.)

To answer your question:

You have access to their birthyear, so in that case you likely have a Person class with a someperson.birthdate field. In that case, you have to ask yourself, is someperson.age a value that is reusable?

The answer is yes. We often care about age more than the birthdate, so if the birthdate is a field, age should definitely be a derived field. (A case where we would not do this: if we were calculating values like someperson.chanceIsFemale or someperson.positionToDisplayInGrid or other irrelevant values, we would not extend the Person class; you just ask yourself, "Would another program care about the fields I am thinking of extending the class with?" The answer to that question will determine if you extend the original class, or make a function (or your own class like PersonAnalysisData or something).)

Tomcat is not deploying my web project from Eclipse

I had the same problem. I fixed it by makinbg the following entry in org.eclipse.wst.common.project.facet.core.xml

<runtime name="Apache Tomcat v7.0" />

Now this complete file looks like -

<?xml version="1.0" encoding="UTF-8"?>
<faceted-project>
    <runtime name="Apache Tomcat v7.0" />
    <fixed facet="wst.jsdt.web" />
    <installed facet="java" version="1.5" />
    <installed facet="jst.web" version="2.3" />
    <installed facet="wst.jsdt.web" version="1.0" />
</faceted-project>

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

Call next function like

byte[] m_Bytes = StreamHelper.ReadToEnd (mystream);

Function:

public static byte[] ReadToEnd(System.IO.Stream stream)
{
    long originalPosition = 0;

    if(stream.CanSeek)
    {
         originalPosition = stream.Position;
         stream.Position = 0;
    }

    try
    {
        byte[] readBuffer = new byte[4096];

        int totalBytesRead = 0;
        int bytesRead;

        while ((bytesRead = stream.Read(readBuffer, totalBytesRead, readBuffer.Length - totalBytesRead)) > 0)
        {
            totalBytesRead += bytesRead;

            if (totalBytesRead == readBuffer.Length)
            {
                int nextByte = stream.ReadByte();
                if (nextByte != -1)
                {
                    byte[] temp = new byte[readBuffer.Length * 2];
                    Buffer.BlockCopy(readBuffer, 0, temp, 0, readBuffer.Length);
                    Buffer.SetByte(temp, totalBytesRead, (byte)nextByte);
                    readBuffer = temp;
                    totalBytesRead++;
                }
            }
        }

        byte[] buffer = readBuffer;
        if (readBuffer.Length != totalBytesRead)
        {
            buffer = new byte[totalBytesRead];
            Buffer.BlockCopy(readBuffer, 0, buffer, 0, totalBytesRead);
        }
        return buffer;
    }
    finally
    {
        if(stream.CanSeek)
        {
             stream.Position = originalPosition; 
        }
    }
}

Change background color of edittext in android

Here the best way

First : make new xml file in res/drawable name it rounded_edit_text then paste this:

<?xml version="1.0" encoding="utf-8"?>
<shape  xmlns:android="http://schemas.android.com/apk/res/android" 
    android:shape="rectangle" android:padding="10dp">
    <solid android:color="#F9966B" />
    <corners
        android:bottomRightRadius="15dp"
        android:bottomLeftRadius="15dp"
        android:topLeftRadius="15dp"
        android:topRightRadius="15dp" />
</shape>

Second: in res/layout copy and past following code (code of EditText)

<EditText
    android:id="@+id/txtdoctor"
    android:layout_width="match_parent"
    android:layout_height="30dp"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:background="@drawable/rounded_edit_text"
    android:ems="10" >
    <requestFocus />
</EditText>

I am getting Failed to load resource: net::ERR_BLOCKED_BY_CLIENT with Google chrome

You can also just run chrome in incognito mode, that automatically switches off all your plugins/extensions, including any add blockers. Then you can quickly see if the extensions are causing the problem.

Why does CreateProcess give error 193 (%1 is not a valid Win32 app)

If you are Clion/anyOtherJetBrainsIDE user, and yourFile.exe cause this problem, just delete it and let the app create and link it with libs from a scratch. It helps.

Convert array to string in NodeJS

toString is a function, not a property. You'll want this:

console.log(aa.toString());

Alternatively, use join to specify the separator (toString() === join(','))

console.log(aa.join(' and '));

CSS media query to target iPad and iPad only?

I am a bit late to answer this but none of the above worked for me.

This is what worked for me

@media only screen and (min-device-width: 768px) and (max-device-width: 1024px) {
    //your styles here
   }

Why do people use Heroku when AWS is present? What distinguishes Heroku from AWS?

It's been a significant percentage of our business migrating people from Heroku to AWS. There are advantages to both, but it's gets messy on Heroku after a while... once you need a certain level of complexity no longer easy to maintain with Heroku's limitations.

That said, there are increasingly options to have the ease of Heroku and the flexibility of AWS by being on AWS with great frameworks/tools.

HTTP test server accepting GET/POST requests

https://httpbin.org/

It echoes the data used in your request for any of these types:

Using str_replace so that it only acts on the first match?

Here's a simple class I created to wrap our slightly modified str_replace() functions.

Our php::str_rreplace() function also allows you to carry out a reverse, limited str_replace() which can be very handy when trying to replace only the final X instance(s) of a string.

These examples both use preg_replace().

<?php
class php {

    /**
    * str_replace() from the end of a string that can also be limited e.g. replace only the last instance of '</div>' with ''
    *
    * @param string   $find
    * @param string   $replace
    * @param string   $subject
    * @param int      $replacement_limit | -1 to replace all references
    *
    * @return string
    */
    public static function str_replace($find, $replace, $subject, $replacement_limit = -1) {
        $find_pattern = str_replace('/', '\/', $find);
        return preg_replace('/' . $find_pattern . '/', $replace, $subject, $replacement_limit);
    }

    /**
    * str_replace() from the end of a string that can also be limited e.g. replace only the last instance of '</div>' with ''
    *
    * @param string   $find
    * @param string   $replace
    * @param string   $subject
    * @param int      $replacement_limit | -1 to replace all references
    *
    * @return string
    */
    public static function str_rreplace($find, $replace, $subject, $replacement_limit = -1) {
        return strrev( self::str_replace(strrev($find), strrev($replace), strrev($subject), $replacement_limit) );
    }
}

Sample settings.xml

Here's the stock "settings.xml" with comments (complete/unchopped file at the bottom)

License:

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

<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

Main docs and top:

<!--
 | This is the configuration file for Maven. It can be specified at two levels:
 |
 |  1. User Level. This settings.xml file provides configuration for a single
 |                 user, and is normally provided in
 |                 ${user.home}/.m2/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -s /path/to/user/settings.xml
 |
 |  2. Global Level. This settings.xml file provides configuration for all
 |                 Maven users on a machine (assuming they're all using the
 |                 same Maven installation). It's normally provided in
 |                 ${maven.home}/conf/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -gs /path/to/global/settings.xml
 |
 | The sections in this sample file are intended to give you a running start
 | at getting the most out of your Maven installation. Where appropriate, the
 | default values (values used when the setting is not specified) are provided.
 |
 |-->
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">

Local repository, interactive mode, plugin groups:

  <!-- localRepository
   | The path to the local repository maven will use to store artifacts.
   |
   | Default: ~/.m2/repository
  <localRepository>/path/to/local/repo</localRepository>
  -->

  <!-- interactiveMode
   | This will determine whether maven prompts you when it needs input. If set
   | to false, maven will use a sensible default value, perhaps based on some
   | other setting, for the parameter in question.
   |
   | Default: true
  <interactiveMode>true</interactiveMode>
  -->

  <!-- offline
   | Determines whether maven should attempt to connect to the network when
   | executing a build. This will have an effect on artifact downloads,
   | artifact deployment, and others.
   |
   | Default: false
  <offline>false</offline>
  -->

  <!-- pluginGroups
   | This is a list of additional group identifiers that will be searched when
   | resolving plugins by their prefix, i.e. when invoking a command line like
   | "mvn prefix:goal". Maven will automatically add the group identifiers
   | "org.apache.maven.plugins" and "org.codehaus.mojo" if these are not
   | already contained in the list.
   |-->
  <pluginGroups>
    <!-- pluginGroup
     | Specifies a further group identifier to use for plugin lookup.
    <pluginGroup>com.your.plugins</pluginGroup>
    -->
  </pluginGroups>

Proxies:

  <!-- proxies
   | This is a list of proxies which can be used on this machine to connect to
   | the network. Unless otherwise specified (by system property or command-
   | line switch), the first proxy specification in this list marked as active
   | will be used.
   |-->
  <proxies>
    <!-- proxy
     | Specification for one proxy, to be used in connecting to the network.
     |
    <proxy>
      <id>optional</id>
      <active>true</active>
      <protocol>http</protocol>
      <username>proxyuser</username>
      <password>proxypass</password>
      <host>proxy.host.net</host>
      <port>80</port>
      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
    </proxy>
    -->
  </proxies>

Servers:

  <!-- servers
   | This is a list of authentication profiles, keyed by the server-id used
   | within the system. Authentication profiles can be used whenever maven must
   | make a connection to a remote server.
   |-->
  <servers>
    <!-- server
     | Specifies the authentication information to use when connecting to a
     | particular server, identified by a unique name within the system
     | (referred to by the 'id' attribute below).
     |
     | NOTE: You should either specify username/password OR
     |       privateKey/passphrase, since these pairings are used together.
     |
    <server>
      <id>deploymentRepo</id>
      <username>repouser</username>
      <password>repopwd</password>
    </server>
    -->

    <!-- Another sample, using keys to authenticate.
    <server>
      <id>siteServer</id>
      <privateKey>/path/to/private/key</privateKey>
      <passphrase>optional; leave empty if not used.</passphrase>
    </server>
    -->
  </servers>

Mirrors:

  <!-- mirrors
   | This is a list of mirrors to be used in downloading artifacts from remote
   | repositories.
   |
   | It works like this: a POM may declare a repository to use in resolving
   | certain artifacts. However, this repository may have problems with heavy
   | traffic at times, so people have mirrored it to several places.
   |
   | That repository definition will have a unique id, so we can create a
   | mirror reference for that repository, to be used as an alternate download
   | site. The mirror site will be the preferred server for that repository.
   |-->
  <mirrors>
    <!-- mirror
     | Specifies a repository mirror site to use instead of a given repository.
     | The repository that this mirror serves has an ID that matches the
     | mirrorOf element of this mirror. IDs are used for inheritance and direct
     | lookup purposes, and must be unique across the set of mirrors.
     |
    <mirror>
      <id>mirrorId</id>
      <mirrorOf>repositoryId</mirrorOf>
      <name>Human Readable Name for this Mirror.</name>
      <url>http://my.repository.com/repo/path</url>
    </mirror>
     -->
  </mirrors>

Profiles (1/3):

  <!-- profiles
   | This is a list of profiles which can be activated in a variety of ways,
   | and which can modify the build process. Profiles provided in the
   | settings.xml are intended to provide local machine-specific paths and
   | repository locations which allow the build to work in the local
   | environment.
   |
   | For example, if you have an integration testing plugin - like cactus -
   | that needs to know where your Tomcat instance is installed, you can
   | provide a variable here such that the variable is dereferenced during the
   | build process to configure the cactus plugin.
   |
   | As noted above, profiles can be activated in a variety of ways. One
   | way - the activeProfiles section of this document (settings.xml) - will be
   | discussed later. Another way essentially relies on the detection of a
   | system property, either matching a particular value for the property, or
   | merely testing its existence. Profiles can also be activated by JDK
   | version prefix, where a value of '1.4' might activate a profile when the
   | build is executed on a JDK version of '1.4.2_07'. Finally, the list of
   | active profiles can be specified directly from the command line.
   |
   | NOTE: For profiles defined in the settings.xml, you are restricted to
   |       specifying only artifact repositories, plugin repositories, and
   |       free-form properties to be used as configuration variables for
   |       plugins in the POM.
   |
   |-->

Profiles (2/3):

  <profiles>
    <!-- profile
     | Specifies a set of introductions to the build process, to be activated
     | using one or more of the mechanisms described above. For inheritance
     | purposes, and to activate profiles via <activatedProfiles/> or the
     | command line, profiles have to have an ID that is unique.
     |
     | An encouraged best practice for profile identification is to use a
     | consistent naming convention for profiles, such as 'env-dev',
     | 'env-test', 'env-production', 'user-jdcasey', 'user-brett', etc. This
     | will make it more intuitive to understand what the set of introduced
     | profiles is attempting to accomplish, particularly when you only have a
     | list of profile id's for debug.
     |
     | This profile example uses the JDK version to trigger activation, and
     | provides a JDK-specific repo.
    <profile>
      <id>jdk-1.4</id>

      <activation>
        <jdk>1.4</jdk>
      </activation>

      <repositories>
        <repository>
          <id>jdk14</id>
          <name>Repository for JDK 1.4 builds</name>
          <url>http://www.myhost.com/maven/jdk14</url>
          <layout>default</layout>
          <snapshotPolicy>always</snapshotPolicy>
        </repository>
      </repositories>
    </profile>
    -->

Profiles (3/3):

    <!--
     | Here is another profile, activated by the system property 'target-env'
     | with a value of 'dev', which provides a specific path to the Tomcat
     | instance. To use this, your plugin configuration might hypothetically
     | look like:
     |
     | ...
     | <plugin>
     |   <groupId>org.myco.myplugins</groupId>
     |   <artifactId>myplugin</artifactId>
     |
     |   <configuration>
     |     <tomcatLocation>${tomcatPath}</tomcatLocation>
     |   </configuration>
     | </plugin>
     | ...
     |
     | NOTE: If you just wanted to inject this configuration whenever someone
     |       set 'target-env' to anything, you could just leave off the
     |       <value/> inside the activation-property.
     |
    <profile>
      <id>env-dev</id>

      <activation>
        <property>
          <name>target-env</name>
          <value>dev</value>
        </property>
      </activation>

      <properties>
        <tomcatPath>/path/to/tomcat/instance</tomcatPath>
      </properties>
    </profile>
    -->
  </profiles>

Bottom:

  <!-- activeProfiles
   | List of profiles that are active for all builds.
   |
  <activeProfiles>
    <activeProfile>alwaysActiveProfile</activeProfile>
    <activeProfile>anotherAlwaysActiveProfile</activeProfile>
  </activeProfiles>
  -->
</settings>

Complete file:


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

<!--
Licensed to the Apache Software Foundation (ASF) under one
or more contributor license agreements.  See the NOTICE file
distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing,
software distributed under the License is distributed on an
"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
KIND, either express or implied.  See the License for the
specific language governing permissions and limitations
under the License.
-->

<!--
 | This is the configuration file for Maven. It can be specified at two levels:
 |
 |  1. User Level. This settings.xml file provides configuration for a single
 |                 user, and is normally provided in
 |                 ${user.home}/.m2/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -s /path/to/user/settings.xml
 |
 |  2. Global Level. This settings.xml file provides configuration for all
 |                 Maven users on a machine (assuming they're all using the
 |                 same Maven installation). It's normally provided in
 |                 ${maven.home}/conf/settings.xml.
 |
 |                 NOTE: This location can be overridden with the CLI option:
 |
 |                 -gs /path/to/global/settings.xml
 |
 | The sections in this sample file are intended to give you a running start
 | at getting the most out of your Maven installation. Where appropriate, the
 | default values (values used when the setting is not specified) are provided.
 |
 |-->
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">

  <!-- localRepository
   | The path to the local repository maven will use to store artifacts.
   |
   | Default: ~/.m2/repository
  <localRepository>/path/to/local/repo</localRepository>
  -->

  <!-- interactiveMode
   | This will determine whether maven prompts you when it needs input. If set
   | to false, maven will use a sensible default value, perhaps based on some
   | other setting, for the parameter in question.
   |
   | Default: true
  <interactiveMode>true</interactiveMode>
  -->

  <!-- offline
   | Determines whether maven should attempt to connect to the network when
   | executing a build. This will have an effect on artifact downloads,
   | artifact deployment, and others.
   |
   | Default: false
  <offline>false</offline>
  -->

  <!-- pluginGroups
   | This is a list of additional group identifiers that will be searched when
   | resolving plugins by their prefix, i.e. when invoking a command line like
   | "mvn prefix:goal". Maven will automatically add the group identifiers
   | "org.apache.maven.plugins" and "org.codehaus.mojo" if these are not
   | already contained in the list.
   |-->
  <pluginGroups>
    <!-- pluginGroup
     | Specifies a further group identifier to use for plugin lookup.
    <pluginGroup>com.your.plugins</pluginGroup>
    -->
  </pluginGroups>

  <!-- proxies
   | This is a list of proxies which can be used on this machine to connect to
   | the network. Unless otherwise specified (by system property or command-
   | line switch), the first proxy specification in this list marked as active
   | will be used.
   |-->
  <proxies>
    <!-- proxy
     | Specification for one proxy, to be used in connecting to the network.
     |
    <proxy>
      <id>optional</id>
      <active>true</active>
      <protocol>http</protocol>
      <username>proxyuser</username>
      <password>proxypass</password>
      <host>proxy.host.net</host>
      <port>80</port>
      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>
    </proxy>
    -->
  </proxies>

  <!-- servers
   | This is a list of authentication profiles, keyed by the server-id used
   | within the system. Authentication profiles can be used whenever maven must
   | make a connection to a remote server.
   |-->
  <servers>
    <!-- server
     | Specifies the authentication information to use when connecting to a
     | particular server, identified by a unique name within the system
     | (referred to by the 'id' attribute below).
     |
     | NOTE: You should either specify username/password OR
     |       privateKey/passphrase, since these pairings are used together.
     |
    <server>
      <id>deploymentRepo</id>
      <username>repouser</username>
      <password>repopwd</password>
    </server>
    -->

    <!-- Another sample, using keys to authenticate.
    <server>
      <id>siteServer</id>
      <privateKey>/path/to/private/key</privateKey>
      <passphrase>optional; leave empty if not used.</passphrase>
    </server>
    -->
  </servers>

  <!-- mirrors
   | This is a list of mirrors to be used in downloading artifacts from remote
   | repositories.
   |
   | It works like this: a POM may declare a repository to use in resolving
   | certain artifacts. However, this repository may have problems with heavy
   | traffic at times, so people have mirrored it to several places.
   |
   | That repository definition will have a unique id, so we can create a
   | mirror reference for that repository, to be used as an alternate download
   | site. The mirror site will be the preferred server for that repository.
   |-->
  <mirrors>
    <!-- mirror
     | Specifies a repository mirror site to use instead of a given repository.
     | The repository that this mirror serves has an ID that matches the
     | mirrorOf element of this mirror. IDs are used for inheritance and direct
     | lookup purposes, and must be unique across the set of mirrors.
     |
    <mirror>
      <id>mirrorId</id>
      <mirrorOf>repositoryId</mirrorOf>
      <name>Human Readable Name for this Mirror.</name>
      <url>http://my.repository.com/repo/path</url>
    </mirror>
     -->
  </mirrors>

  <!-- profiles
   | This is a list of profiles which can be activated in a variety of ways,
   | and which can modify the build process. Profiles provided in the
   | settings.xml are intended to provide local machine-specific paths and
   | repository locations which allow the build to work in the local
   | environment.
   |
   | For example, if you have an integration testing plugin - like cactus -
   | that needs to know where your Tomcat instance is installed, you can
   | provide a variable here such that the variable is dereferenced during the
   | build process to configure the cactus plugin.
   |
   | As noted above, profiles can be activated in a variety of ways. One
   | way - the activeProfiles section of this document (settings.xml) - will be
   | discussed later. Another way essentially relies on the detection of a
   | system property, either matching a particular value for the property, or
   | merely testing its existence. Profiles can also be activated by JDK
   | version prefix, where a value of '1.4' might activate a profile when the
   | build is executed on a JDK version of '1.4.2_07'. Finally, the list of
   | active profiles can be specified directly from the command line.
   |
   | NOTE: For profiles defined in the settings.xml, you are restricted to
   |       specifying only artifact repositories, plugin repositories, and
   |       free-form properties to be used as configuration variables for
   |       plugins in the POM.
   |
   |-->

  <profiles>
    <!-- profile
     | Specifies a set of introductions to the build process, to be activated
     | using one or more of the mechanisms described above. For inheritance
     | purposes, and to activate profiles via <activatedProfiles/> or the
     | command line, profiles have to have an ID that is unique.
     |
     | An encouraged best practice for profile identification is to use a
     | consistent naming convention for profiles, such as 'env-dev',
     | 'env-test', 'env-production', 'user-jdcasey', 'user-brett', etc. This
     | will make it more intuitive to understand what the set of introduced
     | profiles is attempting to accomplish, particularly when you only have a
     | list of profile id's for debug.
     |
     | This profile example uses the JDK version to trigger activation, and
     | provides a JDK-specific repo.
    <profile>
      <id>jdk-1.4</id>

      <activation>
        <jdk>1.4</jdk>
      </activation>

      <repositories>
        <repository>
          <id>jdk14</id>
          <name>Repository for JDK 1.4 builds</name>
          <url>http://www.myhost.com/maven/jdk14</url>
          <layout>default</layout>
          <snapshotPolicy>always</snapshotPolicy>
        </repository>
      </repositories>
    </profile>
    -->

    <!--
     | Here is another profile, activated by the system property 'target-env'
     | with a value of 'dev', which provides a specific path to the Tomcat
     | instance. To use this, your plugin configuration might hypothetically
     | look like:
     |
     | ...
     | <plugin>
     |   <groupId>org.myco.myplugins</groupId>
     |   <artifactId>myplugin</artifactId>
     |
     |   <configuration>
     |     <tomcatLocation>${tomcatPath}</tomcatLocation>
     |   </configuration>
     | </plugin>
     | ...
     |
     | NOTE: If you just wanted to inject this configuration whenever someone
     |       set 'target-env' to anything, you could just leave off the
     |       <value/> inside the activation-property.
     |
    <profile>
      <id>env-dev</id>

      <activation>
        <property>
          <name>target-env</name>
          <value>dev</value>
        </property>
      </activation>

      <properties>
        <tomcatPath>/path/to/tomcat/instance</tomcatPath>
      </properties>
    </profile>
    -->
  </profiles>

  <!-- activeProfiles
   | List of profiles that are active for all builds.
   |
  <activeProfiles>
    <activeProfile>alwaysActiveProfile</activeProfile>
    <activeProfile>anotherAlwaysActiveProfile</activeProfile>
  </activeProfiles>
  -->
</settings>

Access Enum value using EL with JSTL

I generally consider it bad practice to mix java code into jsps/tag files. Using 'eq' should do the trick :

<c:if test="${dp.Status eq 'OLD'}">
  ...
</c:if>

How can I make a checkbox readonly? not disabled?

None of the above worked for me. Here's my vanilla.js solution:

(function() {
    function handleSubmit(event) {
        var form = event.target;
        var nodes = form.querySelectorAll("input[disabled]");
        for (var node of nodes) {
            node.disabled = false;
        }
    }

    function init() {
        var submit_form_tag = document.getElementById('new_whatever');
        submit_form_tag.addEventListener('submit', handleSubmit, true);
    }

    window.onload = init_beworst;

})();

Be sure to provide an appropriate replacement for the form id.

My application has a bit of context, where some boxes are pre-checked, and others you have a limit of how many of the other boxes you can check. When you hit that limit, all the non-pre-checked boxes are disabled, and if you uncheck one all the non-pre-checked boxes are enabled again. When the user presses submit all the checked boxes are submitted to the user, regardless of whether they're pre-checked or not.

npm not working after clearing cache

Try npm cache clean --force if it doesn't work then manually delete %appdata%\npm-cache folder.

It worked for me.

SQL 'LIKE' query using '%' where the search criteria contains '%'

May be this one help :)

DECLARE @SearchCriteria VARCHAR(25)
SET  @SearchCriteria = 'employee'
IF CHARINDEX('%', @SearchCriteria) = 0
BEGIN
SET @SearchCriteria = '%' + @SearchCriteria + '%'
END
SELECT * 
FROM Employee
WHERE Name LIKE @SearchCriteria

Check if program is running with bash shell script?

PROCESS="process name shown in ps -ef"
START_OR_STOP=1        # 0 = start | 1 = stop

MAX=30
COUNT=0

until [ $COUNT -gt $MAX ] ; do
        echo -ne "."
        PROCESS_NUM=$(ps -ef | grep "$PROCESS" | grep -v `basename $0` | grep -v "grep" | wc -l)
        if [ $PROCESS_NUM -gt 0 ]; then
            #runs
            RET=1
        else
            #stopped
            RET=0
        fi

        if [ $RET -eq $START_OR_STOP ]; then
            sleep 5 #wait...
        else
            if [ $START_OR_STOP -eq 1 ]; then
                    echo -ne " stopped"
            else
                    echo -ne " started"
            fi
            echo
            exit 0
        fi
        let COUNT=COUNT+1
done

if [ $START_OR_STOP -eq 1 ]; then
    echo -ne " !!$PROCESS failed to stop!! "
else
    echo -ne " !!$PROCESS failed to start!! "
fi
echo
exit 1

How can I add additional PHP versions to MAMP

Found a quick fix in the MAMP forums.

Basically it seems MAMP is only allowing 2 versions of PHP to show up. Quick fix, rename the folders you're not bothered about using, for me this meant adding an "X" to my /Applications/MAMP/bin/php/php5.4.10_X folder. Now 5.2.17 and 5.3.20 show up in the mamp prefs.

Done!

Edit - if the PHP version you require isn't in the PHP folder, you can download the version you require from http://www.mamp.info/en/downloads/

Edit - MAMP don't seem to provide links to the alternative PHP versions on the download page any more. Use WayBackMachine https://web.archive.org/web/20180131074715/http://www.mamp.info/en/downloads/

Get first element of Series without knowing the index

Use iloc to access by position (rather than label):

In [11]: df = pd.DataFrame([[1, 2], [3, 4]], ['a', 'b'], ['A', 'B'])

In [12]: df
Out[12]: 
   A  B
a  1  2
b  3  4

In [13]: df.iloc[0]  # first row in a DataFrame
Out[13]: 
A    1
B    2
Name: a, dtype: int64

In [14]: df['A'].iloc[0]  # first item in a Series (Column)
Out[14]: 1

How to multiply duration by integer?

It's nice that Go has a Duration type -- having explicitly defined units can prevent real-world problems.

And because of Go's strict type rules, you can't multiply a Duration by an integer -- you must use a cast in order to multiply common types.

/*
MultiplyDuration Hide semantically invalid duration math behind a function
*/
func MultiplyDuration(factor int64, d time.Duration) time.Duration {
    return time.Duration(factor) * d        // method 1 -- multiply in 'Duration'
 // return time.Duration(factor * int64(d)) // method 2 -- multiply in 'int64'
}

The official documentation demonstrates using method #1:

To convert an integer number of units to a Duration, multiply:

seconds := 10
fmt.Print(time.Duration(seconds)*time.Second) // prints 10s

But, of course, multiplying a duration by a duration should not produce a duration -- that's nonsensical on the face of it. Case in point, 5 milliseconds times 5 milliseconds produces 6h56m40s. Attempting to square 5 seconds results in an overflow (and won't even compile if done with constants).

By the way, the int64 representation of Duration in nanoseconds "limits the largest representable duration to approximately 290 years", and this indicates that Duration, like int64, is treated as a signed value: (1<<(64-1))/(1e9*60*60*24*365.25) ~= 292, and that's exactly how it is implemented:

// A Duration represents the elapsed time between two instants
// as an int64 nanosecond count. The representation limits the
// largest representable duration to approximately 290 years.
type Duration int64

So, because we know that the underlying representation of Duration is an int64, performing the cast between int64 and Duration is a sensible NO-OP -- required only to satisfy language rules about mixing types, and it has no effect on the subsequent multiplication operation.

If you don't like the the casting for reasons of purity, bury it in a function call as I have shown above.

Open images? Python

This is how to open any file:

from os import path

filepath = '...' # your path
file = open(filepath, 'r')

What is the simplest way to convert array to vector?

Pointers can be used like any other iterators:

int x[3] = {1, 2, 3};
std::vector<int> v(x, x + 3);
test(v)

how to get GET and POST variables with JQuery?

jQuery plugins seem nice but what I needed is a quick js function to parse the get params. Here is what I have found.

http://www.bloggingdeveloper.com/post/JavaScript-QueryString-ParseGet-QueryString-with-Client-Side-JavaScript.aspx

What is the difference between __init__ and __call__?

I will try to explain this using an example, suppose you wanted to print a fixed number of terms from fibonacci series. Remember that the first 2 terms of fibonacci series are 1s. Eg: 1, 1, 2, 3, 5, 8, 13....

You want the list containing the fibonacci numbers to be initialized only once and after that it should update. Now we can use the __call__ functionality. Read @mudit verma's answer. It's like you want the object to be callable as a function but not re-initialized every time you call it.

Eg:

class Recorder:
    def __init__(self):
        self._weights = []
        for i in range(0, 2):
            self._weights.append(1)
        print self._weights[-1]
        print self._weights[-2]
        print "no. above is from __init__"

    def __call__(self, t):
        self._weights = [self._weights[-1], self._weights[-1] + self._weights[-2]]
        print self._weights[-1]
        print "no. above is from __call__"

weight_recorder = Recorder()
for i in range(0, 10):
    weight_recorder(i)

The output is:

1
1
no. above is from __init__
2
no. above is from __call__
3
no. above is from __call__
5
no. above is from __call__
8
no. above is from __call__
13
no. above is from __call__
21
no. above is from __call__
34
no. above is from __call__
55
no. above is from __call__
89
no. above is from __call__
144
no. above is from __call__

If you observe the output __init__ was called only one time that's when the class was instantiated for the first time, later on the object was being called without re-initializing.

Replace first occurrence of pattern in a string

public string ReplaceFirst(string text, string search, string replace)
{
  int pos = text.IndexOf(search);
  if (pos < 0)
  {
    return text;
  }
  return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}

here is an Extension Method that could also work as well per VoidKing request

public static class StringExtensionMethods
{
    public static string ReplaceFirst(this string text, string search, string replace)
    {
      int pos = text.IndexOf(search);
      if (pos < 0)
      {
        return text;
      }
      return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
    }
}

How to download image from url

Try this it worked for me

Write this in your Controller

public class DemoController: Controller

        public async Task<FileStreamResult> GetLogoImage(string logoimage)
        {
            string str = "" ;
            var filePath = Server.MapPath("~/App_Data/" + SubfolderName);//If subfolder exist otherwise leave.
            // DirectoryInfo dir = new DirectoryInfo(filePath);
            string[] filePaths = Directory.GetFiles(@filePath, "*.*");
            foreach (var fileTemp in filePaths)
            {
                  str= fileTemp.ToString();
            }
                return File(new MemoryStream(System.IO.File.ReadAllBytes(str)), System.Web.MimeMapping.GetMimeMapping(str), Path.GetFileName(str));
        }

Here is my view

<div><a href="/DemoController/GetLogoImage?Type=Logo" target="_blank">Download Logo</a></div>

How does one extract each folder name from a path?

This is good in the general case:

yourPath.Split(@"\/", StringSplitOptions.RemoveEmptyEntries)

There is no empty element in the returned array if the path itself ends in a (back)slash (e.g. "\foo\bar\"). However, you will have to be sure that yourPath is really a directory and not a file. You can find out what it is and compensate if it is a file like this:

if(Directory.Exists(yourPath)) {
  var entries = yourPath.Split(@"\/", StringSplitOptions.RemoveEmptyEntries);
}
else if(File.Exists(yourPath)) {
  var entries = Path.GetDirectoryName(yourPath).Split(
                    @"\/", StringSplitOptions.RemoveEmptyEntries);
}
else {
  // error handling
}

I believe this covers all bases without being too pedantic. It will return a string[] that you can iterate over with foreach to get each directory in turn.

If you want to use constants instead of the @"\/" magic string, you need to use

var separators = new char[] {
  Path.DirectorySeparatorChar,  
  Path.AltDirectorySeparatorChar  
};

and then use separators instead of @"\/" in the code above. Personally, I find this too verbose and would most likely not do it.

Ubuntu, how do you remove all Python 3 but not 2

First of all, don't try the following command as suggested by Germain above.

   `sudo apt-get remove 'python3.*'`

In Ubuntu, many software depends upon Python3 so if you will execute this command it will remove all of them as it happened with me. I found following answer useful to recover it.

https://askubuntu.com/questions/810854/i-deleted-package-python3-on-ubuntu-and-i-have-lost-dashboard-terminal-and-un

If you want to use different python versions for different projects then create virtual environments it will be very useful. refer to the following link to create virtual environments.

Creating Virtual Environment also helps in using Tensorflow and Keras in Jupyter Notebook.

https://linoxide.com/linux-how-to/setup-python-virtual-environment-ubuntu/

Checking from shell script if a directory contains files

The solutions so far use ls. Here's an all bash solution:

#!/bin/bash
shopt -s nullglob dotglob     # To include hidden files
files=(/some/dir/*)
if [ ${#files[@]} -gt 0 ]; then echo "huzzah"; fi

Need a good hex editor for Linux

Personally, I use Emacs with hexl-mod.

Emacs is able to work with really huge files. You can use search/replace value easily. Finally, you can use 'ediff' to do some diffs.

Why does Java have an "unreachable statement" compiler error?

Because unreachable code is meaningless to the compiler. Whilst making code meaningful to people is both paramount and harder than making it meaningful to a compiler, the compiler is the essential consumer of code. The designers of Java take the viewpoint that code that is not meaningful to the compiler is an error. Their stance is that if you have some unreachable code, you have made a mistake that needs to be fixed.

There is a similar question here: Unreachable code: error or warning?, in which the author says "Personally I strongly feel it should be an error: if the programmer writes a piece of code, it should always be with the intention of actually running it in some scenario." Obviously the language designers of Java agree.

Whether unreachable code should prevent compilation is a question on which there will never be consensus. But this is why the Java designers did it.


A number of people in comments point out that there are many classes of unreachable code Java doesn't prevent compiling. If I understand the consequences of Gödel correctly, no compiler can possibly catch all classes of unreachable code.

Unit tests cannot catch every single bug. We don't use this as an argument against their value. Likewise a compiler can't catch all problematic code, but it is still valuable for it to prevent compilation of bad code when it can.

The Java language designers consider unreachable code an error. So preventing it compiling when possible is reasonable.


(Before you downvote: the question is not whether or not Java should have an unreachable statement compiler error. The question is why Java has an unreachable statement compiler error. Don't downvote me just because you think Java made the wrong design decision.)

Condition within JOIN or WHERE

For inner joins I have not really noticed a difference (but as with all performance tuning, you need to check against your database under your conditions).

However where you put the condition makes a huge difference if you are using left or right joins. For instance consider these two queries:

SELECT *
FROM dbo.Customers AS CUS 
LEFT JOIN dbo.Orders AS ORD 
ON CUS.CustomerID = ORD.CustomerID
WHERE ORD.OrderDate >'20090515'

SELECT *
FROM dbo.Customers AS CUS 
LEFT JOIN dbo.Orders AS ORD 
ON CUS.CustomerID = ORD.CustomerID
AND ORD.OrderDate >'20090515'

The first will give you only those records that have an order dated later than May 15, 2009 thus converting the left join to an inner join.

The second will give those records plus any customers with no orders. The results set is very different depending on where you put the condition. (Select * is for example purposes only, of course you should not use this in production code.)

The exception to this is when you want to see only the records in one table but not the other. Then you use the where clause for the condition not the join.

SELECT *
FROM dbo.Customers AS CUS 
LEFT JOIN dbo.Orders AS ORD 
ON CUS.CustomerID = ORD.CustomerID
WHERE ORD.OrderID is null

Swift: Testing optionals for nil

Now you can do in swift the following thing which allows you to regain a little bit of the objective-c if nil else

if textfieldDate.text?.isEmpty ?? true {

}

Arrays vs Vectors: Introductory Similarities and Differences

Those reference pretty much answered your question. Simply put, vectors' lengths are dynamic while arrays have a fixed size. when using an array, you specify its size upon declaration:

int myArray[100];
myArray[0]=1;
myArray[1]=2;
myArray[2]=3;

for vectors, you just declare it and add elements

vector<int> myVector;
myVector.push_back(1);
myVector.push_back(2);
myVector.push_back(3);
...

at times you wont know the number of elements needed so a vector would be ideal for such a situation.

Simple way to convert datarow array to datatable

For .Net Framework 3.5+

DataTable dt = new DataTable();
DataRow[] dr = dt.Select("Your string");
DataTable dt1 = dr.CopyToDataTable();

But if there is no rows in the array, it can cause the errors such as The source contains no DataRows. Therefore, if you decide to use this method CopyToDataTable(), you should check the array to know it has datarows or not.

if (dr.Length > 0)
    DataTable dt1 = dr.CopyToDataTable();

Reference available at MSDN: DataTableExtensions.CopyToDataTable Method (IEnumerable)

jQuery iframe load() event?

use iframe onload event

$('#theiframe').on("load", function() {
    alert(1);
});

How to "Open" and "Save" using java

You want to use a JFileChooser object. It will open and be modal, and block in the thread that opened it until you choose a file.

Open:

JFileChooser fileChooser = new JFileChooser();
if (fileChooser.showOpenDialog(modalToComponent) == JFileChooser.APPROVE_OPTION) {
  File file = fileChooser.getSelectedFile();
  // load from file
}

Save:

JFileChooser fileChooser = new JFileChooser();
if (fileChooser.showSaveDialog(modalToComponent) == JFileChooser.APPROVE_OPTION) {
  File file = fileChooser.getSelectedFile();
  // save to file
}

There are more options you can set to set the file name extension filter, or the current directory. See the API for the javax.swing.JFileChooser for details. There is also a page for "How to Use File Choosers" on Oracle's site:

http://download.oracle.com/javase/tutorial/uiswing/components/filechooser.html

What are the -Xms and -Xmx parameters when starting JVM?

The question itself has already been addressed above. Just adding part of the default values.

As per http://docs.oracle.com/cd/E13150_01/jrockit_jvm/jrockit/jrdocs/refman/optionX.html

The default value of Xmx will depend on platform and amount of memory available in the system.

Bootstrap tab activation with JQuery

This one is quite straightforward from w3schools: https://www.w3schools.com/bootstrap/bootstrap_ref_js_tab.asp

// Select tab by name
$('.nav-tabs a[href="#home"]').tab('show')

// Select first tab
$('.nav-tabs a:first').tab('show') 

// Select last tab
$('.nav-tabs a:last').tab('show') 

// Select fourth tab (zero-based)
$('.nav-tabs li:eq(3) a').tab('show')

JSON Stringify changes time of date because of UTC

Got around this issue by using the moment.js library (the non-timezone version).

var newMinDate = moment(datePicker.selectedDates[0]);
var newMaxDate = moment(datePicker.selectedDates[1]);

// Define the data to ask the server for
var dataToGet = {"ArduinoDeviceIdentifier":"Temperatures",
                "StartDate":newMinDate.format('YYYY-MM-DD HH:mm'),
                "EndDate":newMaxDate.format('YYYY-MM-DD HH:mm')
};

alert(JSON.stringify(dataToGet));

I was using the flatpickr.min.js library. The time of the resulting JSON object created matches the local time provided but the date picker.