Programs & Examples On #Mdf

Master Database File (.MDF) is the starting point of a SQL Server database. It is the primary data file and also points to the other files in the database.

Attach (open) mdf file database with SQL Server Management Studio

I don't know about the older versions but for SSMS 2016 you can go to the Object Explorer and right click on the Databases entry. Then select Attach... in the context menu. Here you can browse to the .mdf file and open it. screenshot

SQL Server: Importing database from .mdf?

To perform this operation see the next images:

enter image description here

and next step is add *.mdf file,

very important, the .mdf file must be located in C:......\MSSQL12.SQLEXPRESS\MSSQL\DATA

enter image description here

Now remove the log file

enter image description here

What is an MDF file?

Just to make this absolutely clear for all:

A .MDF file is “typically” a SQL Server data file however it is important to note that it does NOT have to be.

This is because .MDF is nothing more than a recommended/preferred notation but the extension itself does not actually dictate the file type.

To illustrate this, if someone wanted to create their primary data file with an extension of .gbn they could go ahead and do so without issue.

To qualify the preferred naming conventions:

  • .mdf - Primary database data file.
  • .ndf - Other database data files i.e. non Primary.
  • .ldf - Log data file.

Is it possible to make a Tree View with Angular?

You can use angular-recursion-injector for that: https://github.com/knyga/angular-recursion-injector

Allows you to do unlimited depth nesting with conditioning. Does recompilation only if needed and compiles only right elements. No magic in code.

<div class="node">
  <span>{{name}}</span>

  <node--recursion recursion-if="subNode" ng-model="subNode"></node--recursion>
</div>

One of the things that allows it to work faster and simpler then the other solutions is "--recursion" suffix.

how to specify new environment location for conda create

I ran into a similar situation. I did have access to a larger data drive. Depending on your situation, and the access you have to the server you can consider

ln -s /datavol/path/to/your/.conda /home/user/.conda

Then subsequent conda commands will put data to the symlinked dir in datavol

Convert command line argument to string

It's simple. Just do this:

#include <iostream>
#include <vector>
#include <string.h>

int main(int argc, char *argv[])
{
    std::vector<std::string> argList;
    for(int i=0;i<argc;i++)
        argList.push_back(argv[i]);
    //now you can access argList[n]
}

@Benjamin Lindley You are right. This is not a good solution. Please read the one answered by juanchopanza.

initializing strings as null vs. empty string

There's a function empty() ready for you in std::string:

std::string a;
if(a.empty())
{
    //do stuff. You will enter this block if the string is declared like this
}

or

std::string a;
if(!a.empty())
{
    //You will not enter this block now
}
a = "42";
if(!a.empty())
{
    //And now you will enter this block.
}

How to programmatically set the Image source

Use asp:image

<asp:Image id="Image1" runat="server"
           AlternateText="Image text"
           ImageAlign="left"
           ImageUrl="images/image1.jpg"/>

and codebehind to change image url

Image1.ImageUrl = "/MyProject;component/Images/down.png"; 

How to rename with prefix/suffix?

I've seen people mention a rename command, but it is not routinely available on Unix systems (as opposed to Linux systems, say, or Cygwin - on both of which, rename is an executable rather than a script). That version of rename has a fairly limited functionality:

rename from to file ...

It replaces the from part of the file names with the to, and the example given in the man page is:

rename foo foo0 foo? foo??

This renames foo1 to foo01, and foo10 to foo010, etc.

I use a Perl script called rename, which I originally dug out from the first edition Camel book, circa 1992, and then extended, to rename files.

#!/bin/perl -w
#
# @(#)$Id: rename.pl,v 1.7 2008/02/16 07:53:08 jleffler Exp $
#
# Rename files using a Perl substitute or transliterate command

use strict;
use Getopt::Std;

my(%opts);
my($usage) = "Usage: $0 [-fnxV] perlexpr [filenames]\n";
my($force) = 0;
my($noexc) = 0;
my($trace) = 0;

die $usage unless getopts('fnxV', \%opts);

if ($opts{V})
{
    printf "%s\n", q'RENAME Version $Revision: 1.7 $ ($Date: 2008/02/16 07:53:08 $)';
    exit 0;
}
$force = 1 if ($opts{f});
$noexc = 1 if ($opts{n});
$trace = 1 if ($opts{x});

my($op) = shift;
die $usage unless defined $op;

if (!@ARGV) {
    @ARGV = <STDIN>;
    chop(@ARGV);
}

for (@ARGV)
{
    if (-e $_ || -l $_)
    {
        my($was) = $_;
        eval $op;
        die $@ if $@;
        next if ($was eq $_);
        if ($force == 0 && -f $_)
        {
            print STDERR "rename failed: $was - $_ exists\n";
        }
        else
        {
            print "+ $was --> $_\n" if $trace;
            print STDERR "rename failed: $was - $!\n"
                unless ($noexc || rename($was, $_));
        }
    }
    else
    {
        print STDERR "$_ - $!\n";
    }
}

This allows you to write any Perl substitute or transliterate command to map file names. In the specific example requested, you'd use:

rename 's/^/new./' original.filename

Python function attributes - uses and abuses

I use them sparingly, but they can be pretty convenient:

def log(msg):
   log.logfile.write(msg)

Now I can use log throughout my module, and redirect output simply by setting log.logfile. There are lots and lots of other ways to accomplish that, but this one's lightweight and dirt simple. And while it smelled funny the first time I did it, I've come to believe that it smells better than having a global logfile variable.

Deleting rows with Python in a CSV file

You should have if row[2] != "0". Otherwise it's not checking to see if the string value is equal to 0.

Start redis-server with config file

Okay, redis is pretty user friendly but there are some gotchas.

Here are just some easy commands for working with redis on Ubuntu:

install:

sudo apt-get install redis-server

start with conf:

sudo redis-server <path to conf>
sudo redis-server config/redis.conf

stop with conf:

redis-ctl shutdown

(not sure how this shuts down the pid specified in the conf. Redis must save the path to the pid somewhere on boot)

log:

tail -f /var/log/redis/redis-server.log

Also, various example confs floating around online and on this site were beyond useless. The best, sure fire way to get a compatible conf is to copy-paste the one your installation is already using. You should be able to find it here:

/etc/redis/redis.conf

Then paste it at <path to conf>, tweak as needed and you're good to go.

How to find the foreach index?

Owen has a good answer. If you want just the key, and you are working with an array this might also be useful.

foreach(array_keys($array) as $key) {
//  do stuff
}

Send mail via Gmail with PowerShell V2's Send-MailMessage

Send email with attachment using PowerShell -

      $EmailTo = "[email protected]"  // [email protected]
      $EmailFrom = "[email protected]"  // [email protected]
      $Subject = "zx"  //subject
      $Body = "Test Body"  // Body of message
      $SMTPServer = "smtp.gmail.com" 
      $filenameAndPath = "G:\abc.jpg"  // Attachment
      $SMTPMessage = New-Object System.Net.Mail.MailMessage($EmailFrom, $EmailTo, $Subject, $Body)
      $attachment = New-Object System.Net.Mail.Attachment($filenameAndPath)
      $SMTPMessage.Attachments.Add($attachment)
      $SMTPClient = New-Object Net.Mail.SmtpClient($SmtpServer, 587) 
      $SMTPClient.EnableSsl = $true 
      $SMTPClient.Credentials = New-Object System.Net.NetworkCredential("[email protected]", "xxxxxxxx"); // xxxxxx-password
      $SMTPClient.Send($SMTPMessage)

Differences in boolean operators: & vs && and | vs ||

If an expression involving the Boolean & operator is evaluated, both operands are evaluated. Then the & operator is applied to the operand.

When an expression involving the && operator is evaluated, the first operand is evaluated. If the first operand evaluates to false, the evaluation of the second operand is skipped.

If the first operand returns a value of true then the second operand is evaluated. If the second operand returns a value of true then && operator is then applied to the first and second operands.

Similar for | and ||.

Python: Assign print output to a variable

Please note, I wrote this answer based on Python 3.x. No worries you can assign print() statement to the variable like this.

>>> var = print('some text')
some text
>>> var
>>> type(var)
<class 'NoneType'>

According to the documentation,

All non-keyword arguments are converted to strings like str() does and written to the stream, separated by sep and followed by end. Both sep and end must be strings; they can also be None, which means to use the default values. If no objects are given, print() will just write end.

The file argument must be an object with a write(string) method; if it is not present or None, sys.stdout will be used. Since printed arguments are converted to text strings, print() cannot be used with binary mode file objects. For these, use file.write(...) instead.

That's why we cannot assign print() statement values to the variable. In this question you have ask (or any function). So print() also a function with the return value with None. So the return value of python function is None. But you can call the function(with parenthesis ()) and save the return value in this way.

>>> var = some_function()

So the var variable has the return value of some_function() or the default value None. According to the documentation about print(), All non-keyword arguments are converted to strings like str() does and written to the stream. Lets look what happen inside the str().

Return a string version of object. If object is not provided, returns the empty string. Otherwise, the behavior of str() depends on whether encoding or errors is given, as follows.

So we get a string object, then you can modify the below code line as follows,

>>> var = str(some_function())

or you can use str.join() if you really have a string object.

Return a string which is the concatenation of the strings in iterable. A TypeError will be raised if there are any non-string values in iterable, including bytes objects. The separator between elements is the string providing this method.

change can be as follows,

>>> var = ''.join(some_function())  # you can use this if some_function() really returns a string value

Find row in datatable with specific id

try this code

DataRow foundRow = FinalDt.Rows.Find(Value);

but set at lease one primary key

XSLT equivalent for JSON

I've been really tired of the enormous amount of JavaScript templating engines out there, and all their inline HTML-templates, different markup styles, etc., and decided to build a small library that enables XSLT formatting for JSON data structures. Not rocket science in any way -- it's just JSON parsed to XML and then formatted with a XSLT document. It's fast too, not as fast as JavaScript template engines in Chrome, but in most other browsers it's at least as fast as the JS engine alternative for larger data structures.

Python: can't assign to literal

I got the same error: SyntaxError: can't assign to literal when I was trying to assign multiple variables in a single line.

I was assigning the values as shown below:

    score = 0, isDuplicate = None

When I shifted them to another line, it got resolved:

    score = 0
    isDuplicate = None

I don't know why python does not allow multiple assignments at the same line but that's how it is done.

There is one more way to asisgn it in single line ie. Separate them with a semicolon in place of comma. Check the code below:

score = 0 ; duplicate = None

Multiple lines of text in UILabel

The best solution I have found (to an otherwise frustrating problem that should have been solved in the framework) is similar to vaychick's.

Just set number of lines to 0 in either IB or code

myLabel.numberOfLines = 0;

This will display the lines needed but will reposition the label so its centered horizontally (so that a 1 line and 3 line label are aligned in their horizontal position). To fix that add:

CGRect currentFrame = myLabel.frame;
CGSize max = CGSizeMake(myLabel.frame.size.width, 500);
CGSize expected = [myString sizeWithFont:myLabel.font constrainedToSize:max lineBreakMode:myLabel.lineBreakMode]; 
currentFrame.size.height = expected.height;
myLabel.frame = currentFrame;

Angular 2 'component' is not a known element

I got the same issue, and it was happening because of different feature module included this component by mistake. When removed it from the other feature, it worked!

How can I get the DateTime for the start of the week?

var now = System.DateTime.Now;

var result = now.AddDays(-((now.DayOfWeek - System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat.FirstDayOfWeek + 7) % 7)).Date;

How to change the button color when it is active using bootstrap?

CSS has many pseudo selector like, :active, :hover, :focus, so you can use.

Html

<div class="col-sm-12" id="my_styles">
     <button type="submit" class="btn btn-warning" id="1">Button1</button>
     <button type="submit" class="btn btn-warning" id="2">Button2</button>
</div>

css

.btn{
    background: #ccc;
} .btn:focus{
    background: red;
}

JsFiddle

How to picture "for" loop in block representation of algorithm

Here's a flow chart that illustrates a for loop:

Flow Chart For Loop

The equivalent C code would be

for(i = 2; i <= 6; i = i + 2) {
    printf("%d\t", i + 1);
}

I found this and several other examples on one of Tenouk's C Laboratory practice worksheets.

Git add and commit in one command

You ca use -a

git commit -h

...
Commit contents options
    -a, -all    commit all changed files
...

git commit -a # It will add all files and also will open your default text editor.

Printing pointers in C

Yes, your compiler is expecting void *. Just cast them to void *.

/* for instance... */
printf("The value of s is: %p\n", (void *) s);
printf("The direction of s is: %p\n", (void *) &s);

HTML select drop-down with an input field

You can use input text with "list" attribute, which refers to the datalist of values.

_x000D_
_x000D_
<input type="text" name="city" list="cityname">_x000D_
    <datalist id="cityname">_x000D_
      <option value="Boston">_x000D_
      <option value="Cambridge">_x000D_
    </datalist>
_x000D_
_x000D_
_x000D_

This creates a free text input field that also has a drop-down to select predefined choices. Attribution for example and more information: https://www.w3.org/wiki/HTML/Elements/datalist

how to set the query timeout from SQL connection string

See:- ConnectionStrings content on this subject. There is no default command timeout property.

Change project name on Android Studio

I just went into the manifest and changed android:label="...." to the name of the application. Once Id changed this, the title and the actual app name changed to that :)

How to loop through Excel files and load them into a database using SSIS package?

I ran into an article that illustrates a method where the data from the same excel sheet can be imported in the selected table until there is no modifications in excel with data types.

If the data is inserted or overwritten with new ones, importing process will be successfully accomplished, and the data will be added to the table in SQL database.

The article may be found here: http://www.sqlshack.com/using-ssis-packages-import-ms-excel-data-database/

Hope it helps.

Use a.empty, a.bool(), a.item(), a.any() or a.all()

As user2357112 mentioned in the comments, you cannot use chained comparisons here. For elementwise comparison you need to use &. That also requires using parentheses so that & wouldn't take precedence.

It would go something like this:

mask = ((50  < df['heart rate']) & (101 > df['heart rate']) & (140 < df['systolic...

In order to avoid that, you can build series for lower and upper limits:

low_limit = pd.Series([90, 50, 95, 11, 140, 35], index=df.columns)
high_limit = pd.Series([160, 101, 100, 19, 160, 39], index=df.columns)

Now you can slice it as follows:

mask = ((df < high_limit) & (df > low_limit)).all(axis=1)
df[mask]
Out: 
     dyastolic blood pressure  heart rate  pulse oximetry  respiratory rate  \
17                        136          62              97                15   
69                        110          85              96                18   
72                        105          85              97                16   
161                       126          57              99                16   
286                       127          84              99                12   
435                        92          67              96                13   
499                       110          66              97                15   

     systolic blood pressure  temperature  
17                       141           37  
69                       155           38  
72                       154           36  
161                      153           36  
286                      156           37  
435                      155           36  
499                      149           36  

And for assignment you can use np.where:

df['class'] = np.where(mask, 'excellent', 'critical')

Include CSS and Javascript in my django template

First, create staticfiles folder. Inside that folder create css, js, and img folder.

settings.py

import os

PROJECT_DIR = os.path.dirname(__file__)

DATABASES = {
    'default': {
         'ENGINE': 'django.db.backends.sqlite3', 
         'NAME': os.path.join(PROJECT_DIR, 'myweblabdev.sqlite'),                        
         'USER': '',
         'PASSWORD': '',
         'HOST': '',                      
         'PORT': '',                     
    }
}

MEDIA_ROOT = os.path.join(PROJECT_DIR, 'media')

MEDIA_URL = '/media/'

STATIC_ROOT = os.path.join(PROJECT_DIR, 'static')

STATIC_URL = '/static/'

STATICFILES_DIRS = (
    os.path.join(PROJECT_DIR, 'staticfiles'),
)

main urls.py

from django.conf.urls import patterns, include, url
from django.conf.urls.static import static
from django.contrib import admin
from django.contrib.staticfiles.urls import staticfiles_urlpatterns
from myweblab import settings

admin.autodiscover()

urlpatterns = patterns('',
    .......
) + static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

urlpatterns += staticfiles_urlpatterns()

template

{% load static %}

<link rel="stylesheet" href="{% static 'css/style.css' %}">

Where do I find the bashrc file on Mac?

The .bashrc file is in your home directory.

So from command line do:

cd
ls -a

This will show all the hidden files in your home directory. "cd" will get you home and ls -a will "list all".

In general when you see ~/ the tilda slash refers to your home directory. So ~/.bashrc is your home directory with the .bashrc file.

And the standard path to homebrew is in /usr/local/ so if you:

cd /usr/local
ls | grep -i homebrew

you should see the homebrew directory (/usr/local/homebrew). Source

Yes sometimes you may have to create this file and the typical format of a .bashrc file is:

# .bashrc

# User specific aliases and functions
. .alias
alias ducks='du -cks * | sort -rn | head -15'

# Source global definitions
if [ -f /etc/bashrc ]; then
    . /etc/bashrc
fi

PATH=$PATH:/home/username/bin:/usr/local/homebrew
export PATH

If you create your own .bashrc file make sure that the following line is in your ~/.bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
    . ~/.bashrc
fi

Difference between framework vs Library vs IDE vs API vs SDK vs Toolkits?

The Car Analogy

enter image description here

IDE: The MS Office of Programming. It's where you type your code, plus some added features to make you a happier programmer. (e.g. Eclipse, Netbeans). Car body: It's what you really touch, see and work on.

Library: A library is a collection of functions, often grouped into multiple program files, but packaged into a single archive file. This contains programs created by other folks, so that you don't have to reinvent the wheel. (e.g. junit.jar, log4j.jar). A library generally has a key role, but does all of its work behind the scenes, it doesn't have a GUI. Car's engine.

API: The library publisher's documentation. This is how you should use my library. (e.g. log4j API, junit API). Car's user manual - yes, cars do come with one too!


Kits

What is a kit? It's a collection of many related items that work together to provide a specific service. When someone says medicine kit, you get everything you need for an emergency: plasters, aspirin, gauze and antiseptic, etc.

enter image description here

SDK: McDonald's Happy Meal. You have everything you need (and don't need) boxed neatly: main course, drink, dessert and a bonus toy. An SDK is a bunch of different software components assembled into a package, such that they're "ready-for-action" right out of the box. It often includes multiple libraries and can, but may not necessarily include plugins, API documentation, even an IDE itself. (e.g. iOS Development Kit).

Toolkit: GUI. GUI. GUI. When you hear 'toolkit' in a programming context, it will often refer to a set of libraries intended for GUI development. Since toolkits are UI-centric, they often come with plugins (or standalone IDE's) that provide screen-painting utilities. (e.g. GWT)

Framework: While not the prevalent notion, a framework can be viewed as a kit. It also has a library (or a collection of libraries that work together) that provides a specific coding structure & pattern (thus the word, framework). (e.g. Spring Framework)

jQuery: how do I animate a div rotation?

I needed to rotate an object but have a call back function. Inspired by John Kern's answer I created this.

function animateRotate (object,fromDeg,toDeg,duration,callback){
        var dummy = $('<span style="margin-left:'+fromDeg+'px;">')
        $(dummy).animate({
            "margin-left":toDeg+"px"
        },
        {
            duration:duration,
            step: function(now,fx){
                $(object).css('transform','rotate(' + now + 'deg)');
                if(now == toDeg){
                    if(typeof callback == "function"){
                        callback();
                    }
                }
            }
        }
    )};

Doing this you can simply call the rotate on the object like so... (in my case I'm doing it on a disclosure triangle icon that has already been rotated by default to 270 degress and I'm rotating it another 90 degrees to 360 degrees at 1000 milliseconds. The final argument is the callback after the animation has finished.

animateRotate($(".disclosure_icon"),270,360,1000,function(){
                alert('finished rotate');
            });

highlight the navigation menu for the current page

Please Look at the following:

Here is what's working:

1.) top menu buttons are visible and highlight correctly

2.) sub menu buttons are not visible until top menu is clicked

Here is what needs work:

1.) when sub menu is clicked, looking for new page to keep the selected sub menu open (i will highlight the selected sub menu button for further clarification on navigation)

Please see code here: http://jsbin.com/ePawaju/1/edit

or here: http://www.ceramictilepro.com/_6testingonly.php#

<head>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>

Do I need to put this script in the head section? Where is the best place?

<div class="left">
<nav class="vmenu">
    <ul class="vnavmenu">
        <li data-ref="Top1"><a class="hiLite navBarButton2" href="#">Home</a>
        </li>
    </ul>
    <ul class="Top1 navBarTextSize">
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">sub1</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">sub2</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">sub3</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">sub4</a>
        </li>
    </ul>
    <ul class="vnavmenu">
        <li data-ref="Top2"><a class="hiLite navBarButton2" href="#">Repairs</a>
        </li>
    </ul>
    <ul class="Top2 navBarTextSize">
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">1sub1</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">2sub2</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">3sub3</a>
        </li>
        <li><a class="hiLite navBarButton2_sub" href="http://www.ceramictilepro.com/_5testingonly.php">4sub4</a>
        </li>
    </ul>
</nav>

JQuery is new to me, any help would greatly be appreciated :) var submenu;

$('.vnavmenu li').click(function () {
var elems = $('.vmenu ul:not(.vnavmenu)').length;
var $refClass = $('.' + $(this).attr('data-ref'));
var visible = $refClass.is(':visible');

$('.vmenu ul:not(.vnavmenu)').slideUp(100, function () {

    if (elems == 1) {
        if (!visible) $refClass.slideDown('fast');
    }

    elems--;
});

if (visible) $('#breadcrumbs-pc').animate({
    'margin-top': '0rem'
}, 100);
else $('#breadcrumbs-pc').animate({
    'margin-top': '5rem'
}, 100);
});

Get the value of a dropdown in jQuery

As has been pointed out ... in a select box, the .val() attribute will give you the value of the selected option. If the selected option does not have a value attribute it will default to the display value of the option (which is what the examples on the jQuery documentation of .val show.

you want to use .text() of the selected option:

$('#Crd option:selected').text()

How can I quickly sum all numbers in a file?

It is not easier to replace all new lines by +, add a 0 and send it to the Ruby interpreter?

(sed -e "s/$/+/" file; echo 0)|irb

If you do not have irb, you can send it to bc, but you have to remove all newlines except the last one (of echo). It is better to use tr for this, unless you have a PhD in sed .

(sed -e "s/$/+/" file|tr -d "\n"; echo 0)|bc

curl_exec() always returns false

Error checking and handling is the programmer's friend. Check the return values of the initializing and executing cURL functions. curl_error() and curl_errno() will contain further information in case of failure:

try {
    $ch = curl_init();

    // Check if initialization had gone wrong*    
    if ($ch === false) {
        throw new Exception('failed to initialize');
    }

    curl_setopt($ch, CURLOPT_URL, 'http://example.com/');
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt(/* ... */);

    $content = curl_exec($ch);

    // Check the return value of curl_exec(), too
    if ($content === false) {
        throw new Exception(curl_error($ch), curl_errno($ch));
    }

    /* Process $content here */

    // Close curl handle
    curl_close($ch);
} catch(Exception $e) {

    trigger_error(sprintf(
        'Curl failed with error #%d: %s',
        $e->getCode(), $e->getMessage()),
        E_USER_ERROR);

}

* The curl_init() manual states:

Returns a cURL handle on success, FALSE on errors.

I've observed the function to return FALSE when you're using its $url parameter and the domain could not be resolved. If the parameter is unused, the function might never return FALSE. Always check it anyways, though, since the manual doesn't clearly state what "errors" actually are.

Python - abs vs fabs

abs() : Returns the absolute value as per the argument i.e. if argument is int then it returns int, if argument is float it returns float. Also it works on complex variable also i.e. abs(a+bj) also works and returns absolute value i.e.math.sqrt(((a)**2)+((b)**2)

math.fabs() : It only works on the integer or float values. Always returns the absolute float value no matter what is the argument type(except for the complex numbers).

Prime numbers between 1 to 100 in C Programming Language

#include<stdio.h>
int main()
{
    int a,b,i,c,j;
    printf("\n Enter the two no. in between you want to check:");
    scanf("%d%d",&a,&c);
    printf("%d-%d\n",a,c);
    for(j=a;j<=c;j++)
    {
        b=0;
        for(i=1;i<=c;i++)
        {
            if(j%i==0)
            {
                 b++;
            }
        }
        if(b==2)
        {
            printf("\nPrime number:%d\n",j);
        }
        else
        {
            printf("\n\tNot prime:%d\n",j);
        }
    }
}

How to set an button align-right with Bootstrap?

Try this:

<div class="row">
<div class="alert alert-info" style="min-height:100px;">
    <div class="col-xs-9">
        <a href="#" class="alert-link">Summary:Its some
           description.......testtesttest</a>  
    </div>
    <div class="col-xs-3">
        <button type="button" class="btn btn-primary btn-lg">Large      button</button>
    </div>
 </div>
</div>

Demo:

http://jsfiddle.net/Hx6Sx/1/

How to vertically align elements in a div?

This is my personal solution for an i element inside a div

JSFiddle Example

HTML

<div class="circle">
    <i class="fa fa-plus icon">
</i></div>

CSS

.circle {
   border-radius: 50%;
   color: blue;
   background-color: red;
   height:100px;
   width:100px;
   text-align: center;
   line-height: 100px;
}

.icon {
  font-size: 50px;
  vertical-align: middle;
}

How to delete columns in a CSV file?

Using a dict to grab headings then looping through gets you what you need cleanly.

import csv
ct = 0
cols_i_want = {'cost' : -1, 'date' : -1}
with open("file1.csv","rb") as source:
    rdr = csv.reader( source )
    with open("result","wb") as result:
        wtr = csv.writer( result )
        for row in rdr:
            if ct == 0:
              cc = 0
              for col in row:
                for ciw in cols_i_want: 
                  if col == ciw:
                    cols_i_want[ciw] = cc
                cc += 1
            wtr.writerow( (row[cols_i_want['cost']], row[cols_i_want['date']]) )
            ct += 1

How do I check two or more conditions in one <c:if>?

If you are using JSP 2.0 and above It will come with the EL support: so that you can write in plain english and use and with empty operators to write your test:

<c:if test="${(empty object_1.attribute_A) and (empty object_2.attribute_B)}">

How might I extract the property values of a JavaScript object into an array?

This one worked for me

var dataArray = Object.keys(dataObject).map(function(k){return dataObject[k]});

How to create global variables accessible in all views using Express / Node.JS?

you can also use "global"

Example:

declare like this :

  app.use(function(req,res,next){
      global.site_url = req.headers.host;   // hostname = 'localhost:8080'
      next();
   });

Use like this: in any views or ejs file <% console.log(site_url); %>

in js files console.log(site_url);

Objective-C - Remove last character from string

If it's an NSMutableString (which I would recommend since you're changing it dynamically), you can use:

[myString deleteCharactersInRange:NSMakeRange([myRequestString length]-1, 1)];

String to Binary in C#

Here you go:

public static byte[] ConvertToByteArray(string str, Encoding encoding)
{
    return encoding.GetBytes(str);
}

public static String ToBinary(Byte[] data)
{
    return string.Join(" ", data.Select(byt => Convert.ToString(byt, 2).PadLeft(8, '0')));
}

// Use any sort of encoding you like. 
var binaryString = ToBinary(ConvertToByteArray("Welcome, World!", Encoding.ASCII));

Should I use "camel case" or underscores in python?

PEP 8 advises the first form for readability. You can find it here.

Function names should be lowercase, with words separated by underscores as necessary to improve readability.

Android 6.0 Marshmallow. Cannot write to SD Card

Android Documentation on Manifest.permission.Manifest.permission.WRITE_EXTERNAL_STORAGE states:

Starting in API level 19, this permission is not required to read/write files in your application-specific directories returned by getExternalFilesDir(String) and getExternalCacheDir().


I think that this means you do not have to code for the run-time implementation of the WRITE_EXTERNAL_STORAGE permission unless the app is writing to a directory that is not specific to your app.

You can define the max sdk version in the manifest per permission like:

 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="19" />

Also make sure to change the target SDK in the build.graddle and not the manifest, the gradle settings will always overwrite the manifest settings.

android {
compileSdkVersion 23
buildToolsVersion '23.0.1'
defaultConfig {
    minSdkVersion 17
    targetSdkVersion 22
}

INNER JOIN same table

I think the problem is in your JOIN condition.

SELECT user.user_fname,
       user.user_lname,
       parent.user_fname,
       parent.user_lname
FROM users AS user
JOIN users AS parent 
  ON parent.user_id = user.user_parent_id
WHERE user.user_id = $_GET[id]

Edit: You should probably use LEFT JOIN if there are users with no parents.

How can I strip all punctuation from a string in JavaScript using regex?

For en-US ( American English ) strings this should suffice:

"This., -/ is #! an $ % ^ & * example ;: {} of a = -_ string with `~)() punctuation".replace( /[^a-zA-Z ]/g, '').replace( /\s\s+/g, ' ' )

Be aware that if you support UTF-8 and characters like chinese/russian and all, this will replace them as well, so you really have to specify what you want.

/usr/bin/codesign failed with exit code 1

I just came across this error and it was because I was trying to write the build file to a network drive that was not working. Tried again from my desktop and it worked just fine. (You may have to "Clean" the build after you move it. Just choose "Clean all Targets" from the "Build" drop-down menu).

Tobias is correct though, dig into the details on the code by right-clicking it to see what your specific problem is.

How to create a file name with the current date & time in Python?

Here's some that I needed to include the date-time stamp in the folder name for dumping files from a web scraper.

# import time and OS modules to use to build file folder name
import time
import os 

# Build string for directory to hold files
# Output Configuration
#   drive_letter = Output device location (hard drive) 
#   folder_name = directory (folder) to receive and store PDF files

drive_letter = r'D:\\' 
folder_name = r'downloaded-files'
folder_time = datetime.now().strftime("%Y-%m-%d_%I-%M-%S_%p")
folder_to_save_files = drive_letter + folder_name + folder_time 

# IF no such folder exists, create one automatically
if not os.path.exists(folder_to_save_files):
    os.mkdir(folder_to_save_files)

console.log timestamps in Chrome?

From Chrome 68:

"Show timestamps" moved to settings

The Show timestamps checkbox previously in Console Settings Console Settings has moved to Settings.

enter image description here

List passed by ref - help me explain this behaviour

This link will help you in understanding pass by reference in C#. Basically,when an object of reference type is passed by value to an method, only methods which are available on that object can modify the contents of object.

For example List.sort() method changes List contents but if you assign some other object to same variable, that assignment is local to that method. That is why myList remains unchanged.

If we pass object of reference type by using ref keyword then we can assign some other object to same variable and that changes entire object itself.

(Edit: this is the updated version of the documentation linked above.)

Override intranet compatibility mode IE8

I was able to override compatibility mode by specifying the meta tag as THE FIRST TAG in the head section, not just the first meta tag but as and only as the VERY FIRST TAG.

Thanks to @stefan.s for putting me on to it in your excellent answer. Prior to reading that I had:

THIS DID NOT WORK

<head> 
<link rel="stylesheet" type="text/css" href="/qmuat/plugins/editors/jckeditor/typography/typography.php"/>
<meta http-equiv="x-ua-compatible" content="IE=9" >

moved the link tag out of the way and it worked

THIS WORKS:

<head><meta http-equiv="x-ua-compatible" content="IE=9" >

So an IE8 client set to use compatibility renders the page as IE8 Standard mode - the content='IE=9' means use the highest standard available up to and including IE9.

Elegant Python function to convert CamelCase to snake_case?

This is not a elegant method, is a very 'low level' implementation of a simple state machine (bitfield state machine), possibly the most anti pythonic mode to resolve this, however re module also implements a too complex state machine to resolve this simple task, so i think this is a good solution.

def splitSymbol(s):
    si, ci, state = 0, 0, 0 # start_index, current_index 
    '''
        state bits:
        0: no yields
        1: lower yields
        2: lower yields - 1
        4: upper yields
        8: digit yields
        16: other yields
        32 : upper sequence mark
    '''
    for c in s:

        if c.islower():
            if state & 1:
                yield s[si:ci]
                si = ci
            elif state & 2:
                yield s[si:ci - 1]
                si = ci - 1
            state = 4 | 8 | 16
            ci += 1

        elif c.isupper():
            if state & 4:
                yield s[si:ci]
                si = ci
            if state & 32:
                state = 2 | 8 | 16 | 32
            else:
                state = 8 | 16 | 32

            ci += 1

        elif c.isdigit():
            if state & 8:
                yield s[si:ci]
                si = ci
            state = 1 | 4 | 16
            ci += 1

        else:
            if state & 16:
                yield s[si:ci]
            state = 0
            ci += 1  # eat ci
            si = ci   
        print(' : ', c, bin(state))
    if state:
        yield s[si:ci] 


def camelcaseToUnderscore(s):
    return '_'.join(splitSymbol(s)) 

splitsymbol can parses all case types: UpperSEQUENCEInterleaved, under_score, BIG_SYMBOLS and cammelCasedMethods

I hope it is useful

Backbone.js fetch with parameters

You can also set processData to true:

collection.fetch({ 
    data: { page: 1 },
    processData: true
});

Jquery will auto process data object into param string,

but in Backbone.sync function, Backbone turn the processData off because Backbone will use other method to process data in POST,UPDATE...

in Backbone source:

if (params.type !== 'GET' && !Backbone.emulateJSON) {
    params.processData = false;
}

How to hide html source & disable right click and text copy?

 <body oncontextmenu="return false">

Use this code to disable right click.

Difference between `constexpr` and `const`

An overview of the const and constexpr keywords

In C ++, if a const object is initialized with a constant expression, we can use our const object wherever a constant expression is required.

const int x = 10;
int a[x] = {0};

For example, we can make a case statement in switch.

constexpr can be used with arrays.

constexpr is not a type.

The constexpr keyword can be used in conjunction with the auto keyword.

constexpr auto x = 10;

struct Data {   // We can make a bit field element of struct.   
    int a:x;
 };

If we initialize a const object with a constant expression, the expression generated by that const object is now a constant expression as well.

Constant Expression : An expression whose value can be calculated at compile time.

x*5-4 // This is a constant expression. For the compiler, there is no difference between typing this expression and typing 46 directly.

Initialize is mandatory. It can be used for reading purposes only. It cannot be changed. Up to this point, there is no difference between the "const" and "constexpr" keywords.

NOTE: We can use constexpr and const in the same declaration.

constexpr const int* p;

Constexpr Functions

Normally, the return value of a function is obtained at runtime. But calls to constexpr functions will be obtained as a constant in compile time when certain conditions are met.

NOTE : Arguments sent to the parameter variable of the function in function calls or to all parameter variables if there is more than one parameter, if C.E the return value of the function will be calculated in compile time. !!!

constexpr int square (int a){
return a*a;
}

constexpr int a = 3;
constexpr int b = 5;

int arr[square(a*b+20)] = {0}; //This expression is equal to int arr[35] = {0};

In order for a function to be a constexpr function, the return value type of the function and the type of the function's parameters must be in the type category called "literal type".

The constexpr functions are implicitly inline functions.

An important point :

None of the constexpr functions need to be called with a constant expression.It is not mandatory. If this happens, the computation will not be done at compile time. It will be treated like a normal function call. Therefore, where the constant expression is required, we will no longer be able to use this expression.

The conditions required to be a constexpr function are shown below;

1 ) The types used in the parameters of the function and the type of the return value of the function must be literal type.

2 ) A local variable with static life time should not be used inside the function.

3 ) If the function is legal, when we call this function with a constant expression in compile time, the compiler calculates the return value of the function in compile time.

4 ) The compiler needs to see the code of the function, so constexpr functions will almost always be in the header files.

5 ) In order for the function we created to be a constexpr function, the definition of the function must be in the header file.Thus, whichever source file includes that header file will see the function definition.

Bonus

Normally with Default Member Initialization, static data members with const and integral types can be initialized within the class. However, in order to do this, there must be both "const" and "integral types".

If we use static constexpr then it doesn't have to be an integral type to initialize it inside the class. As long as I initialize it with a constant expression, there is no problem.

class Myclass  {
         const static int sx = 15;         // OK
         constexpr static int sy = 15;     // OK
         const static double sd = 1.5;     // ERROR
         constexpr static double sd = 1.5; // OK
 };

JQuery: dynamic height() with window resize()

To see the window height while (or after) it is resized, try it:

$(window).resize(function() {
$('body').prepend('<div>' + $(window).height() - 46 + '</div>');
});

How can I enable "URL Rewrite" Module in IIS 8.5 in Server 2012?

First, install the URL Rewrite from a download or from the Web Platform Installer. Second, restart IIS. And, finally, close IIS and open again. The last step worked for me.

SQL Query for Selecting Multiple Records

You can try this
SELECT * FROM Buses WHERE BusID in (1,2,3,4,...)

How to convert a JSON string to a dictionary?

Warning: this is a convenience method to convert a JSON string to a dictionary if, for some reason, you have to work from a JSON string. But if you have the JSON data available, you should instead work with the data, without using a string at all.

Swift 3

func convertToDictionary(text: String) -> [String: Any]? {
    if let data = text.data(using: .utf8) {
        do {
            return try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any]
        } catch {
            print(error.localizedDescription)
        }
    }
    return nil
}

let str = "{\"name\":\"James\"}"

let dict = convertToDictionary(text: str)

Swift 2

func convertStringToDictionary(text: String) -> [String:AnyObject]? {
    if let data = text.dataUsingEncoding(NSUTF8StringEncoding) {
        do {
            return try NSJSONSerialization.JSONObjectWithData(data, options: []) as? [String:AnyObject]
        } catch let error as NSError {
            print(error)
        }
    }
    return nil
}

let str = "{\"name\":\"James\"}"

let result = convertStringToDictionary(str)

Original Swift 1 answer:

func convertStringToDictionary(text: String) -> [String:String]? {
    if let data = text.dataUsingEncoding(NSUTF8StringEncoding) {
        var error: NSError?
        let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: &error) as? [String:String]
        if error != nil {
            println(error)
        }
        return json
    }
    return nil
}

let str = "{\"name\":\"James\"}"

let result = convertStringToDictionary(str) // ["name": "James"]

if let name = result?["name"] { // The `?` is here because our `convertStringToDictionary` function returns an Optional
    println(name) // "James"
}

In your version, you didn't pass the proper parameters to NSJSONSerialization and forgot to cast the result. Also, it's better to check for the possible error. Last note: this works only if your value is a String. If it could be another type, it would be better to declare the dictionary conversion like this:

let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: &error) as? [String:AnyObject]

and of course you would also need to change the return type of the function:

func convertStringToDictionary(text: String) -> [String:AnyObject]? { ... }

Installing specific laravel version with composer create-project

From the composer help create-project command

The create-project command creates a new project from a given
package into a new directory. If executed without params and in a directory with a composer.json file it installs the packages for the current project.
You can use this command to bootstrap new projects or setup a clean
version-controlled installation for developers of your project.

[version]
You can also specify the version with the package name using = or : as separator.

To install unstable packages, either specify the version you want, or use the --stability=dev (where dev can be one of RC, beta, alpha or dev).

This command works:

composer create-project laravel/laravel=4.1.27 your-project-name --prefer-dist

This works with the * notation.

How to read attribute value from XmlNode in C#?

Yet another solution:

string s = "??"; // or whatever

if (chldNode.Attributes.Cast<XmlAttribute>()
                       .Select(x => x.Value)
                       .Contains(attributeName))   
   s =  xe.Attributes[attributeName].Value;

It also avoids the exception when the expected attribute attributeName actually doesn't exist.

Cloning a private Github repo

Cloning Private Repository using HTTPS in Year 2020

If maintainer of repository has given Developer access to you on his private library ,you need to first login to https://gitlab.com/users/sign_in with user for which you have received invitation,you will be prompted to change your password,once you change your password then you can successfully clone repository ,pull and push changes to it.

Using Pandas to pd.read_excel() for multiple worksheets of the same workbook

If:

  • you want multiple, but not all, worksheets, and
  • you want a single df as an output

Then, you can pass a list of worksheet names. Which you could populate manually:

import pandas as pd
    
path = "C:\\Path\\To\\Your\\Data\\"
file = "data.xlsx"
sheet_lst_wanted = ["01_SomeName","05_SomeName","12_SomeName"] # tab names from Excel

### import and compile data ###
    
# read all sheets from list into an ordered dictionary    
dict_temp = pd.read_excel(path+file, sheet_name= sheet_lst_wanted)

# concatenate the ordered dict items into a dataframe
df = pd.concat(dict_temp, axis=0, ignore_index=True)

OR

A bit of automation is possible if your desired worksheets have a common naming convention that also allows you to differentiate from unwanted sheets:

# substitute following block for the sheet_lst_wanted line in above block

import xlrd

# string common to only worksheets you want
str_like = "SomeName" 
    
### create list of sheet names in Excel file ###
xls = xlrd.open_workbook(path+file, on_demand=True)
sheet_lst = xls.sheet_names()
    
### create list of sheets meeting criteria  ###
sheet_lst_wanted = []
    
for s in sheet_lst:
    # note: following conditional statement based on my sheets ending with the string defined in sheet_like
    if s[-len(str_like):] == str_like:
        sheet_lst_wanted.append(s)
    else:
        pass

Importing larger sql files into MySQL

We have experienced the same issue when moving the sql server in-house.

A good solution that we ended up using is splitting the sql file into chunks. There are several ways to do that. Use

http://www.ozerov.de/bigdump/ seems good (but never used it)

http://www.rusiczki.net/2007/01/24/sql-dump-file-splitter/ used it and it was very useful to get structure out of the mess and you can take it from there.

Hope this helps :)

Twitter bootstrap modal-backdrop doesn't disappear

Using toggle instead of hide, solved my problem

sort csv by column

import operator
sortedlist = sorted(reader, key=operator.itemgetter(3), reverse=True)

or use lambda

sortedlist = sorted(reader, key=lambda row: row[3], reverse=True)

How to use PHP's password_hash to hash and verify passwords

Yes you understood it correctly, the function password_hash() will generate a salt on its own, and includes it in the resulting hash-value. Storing the salt in the database is absolutely correct, it does its job even if known.

// Hash a new password for storing in the database.
// The function automatically generates a cryptographically safe salt.
$hashToStoreInDb = password_hash($_POST['password'], PASSWORD_DEFAULT);

// Check if the hash of the entered login password, matches the stored hash.
// The salt and the cost factor will be extracted from $existingHashFromDb.
$isPasswordCorrect = password_verify($_POST['password'], $existingHashFromDb);

The second salt you mentioned (the one stored in a file), is actually a pepper or a server side key. If you add it before hashing (like the salt), then you add a pepper. There is a better way though, you could first calculate the hash, and afterwards encrypt (two-way) the hash with a server-side key. This gives you the possibility to change the key when necessary.

In contrast to the salt, this key should be kept secret. People often mix it up and try to hide the salt, but it is better to let the salt do its job and add the secret with a key.

Convert month int to month name

CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(
    Convert.ToInt32(e.Row.Cells[7].Text.Substring(3,2))).Substring(0,3) 
    + "-" 
    + Convert.ToDateTime(e.Row.Cells[7].Text).ToString("yyyy");

Encrypt Password in Configuration Files?

Depending on how secure you need the configuration files or how reliable your application is, http://activemq.apache.org/encrypted-passwords.html may be a good solution for you.

If you are not too afraid of the password being decrypted and it can be really simple to configure using a bean to store the password key. However, if you need more security you can set an environment variable with the secret and remove it after launch. With this you have to worry about the application / server going down and not application not automatically relaunching.

Dependent DLL is not getting copied to the build output folder in Visual Studio

Other than the common ones above, I had a multi-project solution to publish. Apparently some files target different frameworks.

So my solution: Properties > Specific Version (False)

When are you supposed to use escape instead of encodeURI / encodeURIComponent?

I've found that experimenting with the various methods is a good sanity check even after having a good handle of what their various uses and capabilities are.

Towards that end I have found this website extremely useful to confirm my suspicions that I am doing something appropriately. It has also proven useful for decoding an encodeURIComponent'ed string which can be rather challenging to interpret. A great bookmark to have:

http://www.the-art-of-web.com/javascript/escape/

Why should I use core.autocrlf=true in Git?

Update 2:

Xcode 9 appears to have a "feature" where it will ignore the file's current line endings, and instead just use your default line-ending setting when inserting lines into a file, resulting in files with mixed line endings.

I'm pretty sure this bug didn't exist in Xcode 7; not sure about Xcode 8. The good news is that it appears to be fixed in Xcode 10.

For the time it existed, this bug caused a small amount of hilarity in the codebase I refer to in the question (which to this day uses autocrlf=false), and led to many "EOL" commit messages and eventually to my writing a git pre-commit hook to check for/prevent introducing mixed line endings.

Update:

Note: As noted by VonC, starting from Git 2.8, merge markers will not introduce Unix-style line-endings to a Windows-style file.

Original:

One little hiccup that I've noticed with this setup is that when there are merge conflicts, the lines git adds to mark up the differences do not have Windows line-endings, even when the rest of the file does, and you can end up with a file with mixed line endings, e.g.:

// Some code<CR><LF>
<<<<<<< Updated upstream<LF>
// Change A<CR><LF>
=======<LF>
// Change B<CR><LF>
>>>>>>> Stashed changes<LF>
// More code<CR><LF>

This doesn't cause us any problems (I imagine any tool that can handle both types of line-endings will also deal sensible with mixed line-endings--certainly all the ones we use do), but it's something to be aware of.

The other thing* we've found, is that when using git diff to view changes to a file that has Windows line-endings, lines that have been added display their carriage returns, thus:

    // Not changed

+   // New line added in^M
+^M
    // Not changed
    // Not changed

* It doesn't really merit the term: "issue".

How do I compare version numbers in Python?

Posting my full function based on Kindall's solution. I was able to support any alphanumeric characters mixed in with the numbers by padding each version section with leading zeros.

While certainly not as pretty as his one-liner function, it seems to work well with alpha-numeric version numbers. (Just be sure to set the zfill(#) value appropriately if you have long strings in your versioning system.)

def versiontuple(v):
   filled = []
   for point in v.split("."):
      filled.append(point.zfill(8))
   return tuple(filled)

.

>>> versiontuple("10a.4.5.23-alpha") > versiontuple("2a.4.5.23-alpha")
True


>>> "10a.4.5.23-alpha" > "2a.4.5.23-alpha"
False

For loop for HTMLCollection elements

You can't use for/in on NodeLists or HTMLCollections. However, you can use some Array.prototype methods, as long as you .call() them and pass in the NodeList or HTMLCollection as this.

So consider the following as an alternative to jfriend00's for loop:

var list= document.getElementsByClassName("events");
[].forEach.call(list, function(el) {
    console.log(el.id);
});

There's a good article on MDN that covers this technique. Note their warning about browser compatibility though:

[...] passing a host object (like a NodeList) as this to a native method (such as forEach) is not guaranteed to work in all browsers and is known to fail in some.

So while this approach is convenient, a for loop may be the most browser-compatible solution.

Update (Aug 30, 2014): Eventually you'll be able to use ES6 for/of!

var list = document.getElementsByClassName("events");
for (const el of list)
  console.log(el.id);

It's already supported in recent versions of Chrome and Firefox.

How to copy Docker images from one host to another without using a repository

You will need to save the Docker image as a tar file:

docker save -o <path for generated tar file> <image name>

Then copy your image to a new system with regular file transfer tools such as cp, scp or rsync(preferred for big files). After that you will have to load the image into Docker:

docker load -i <path to image tar file>

PS: You may need to sudo all commands.

EDIT: You should add filename (not just directory) with -o, for example:

docker save -o c:/myfile.tar centos:16

Allowing Untrusted SSL Certificates with HttpClient

Or you can use for the HttpClient in the Windows.Web.Http namespace:

var filter = new HttpBaseProtocolFilter();
#if DEBUG
    filter.IgnorableServerCertificateErrors.Add(ChainValidationResult.Expired);
    filter.IgnorableServerCertificateErrors.Add(ChainValidationResult.Untrusted);
    filter.IgnorableServerCertificateErrors.Add(ChainValidationResult.InvalidName);
#endif
using (var httpClient = new HttpClient(filter)) {
    ...
}

How to export query result to csv in Oracle SQL Developer?

To take an export to your local system from sql developer.

Path : C:\Source_Table_Extract\des_loan_due_dtls_src_boaf.csv

    SPOOL "Path where you want to save the file"
    SELECT /*csv*/ * FROM TABLE_NAME;

How to generate Javadoc from command line

Oracle provides some simple examples:

http://docs.oracle.com/javase/8/docs/technotes/tools/windows/javadoc.html#CHDJBGFC

Assuming you are in ~/ and the java source tree is in ./saxon_source/net and you want to recurse through the whole source tree net is both a directory and the top package name.

mkdir saxon_docs
javadoc -d saxon_docs -sourcepath saxon_source -subpackages net

Remove the last three characters from a string

myString.Remove(myString.Length-3);

How to break out of while loop in Python?

Don't use while True and break statements. It's bad programming.

Imagine you come to debug someone else's code and you see a while True on line 1 and then have to trawl your way through another 200 lines of code with 15 break statements in it, having to read umpteen lines of code for each one to work out what actually causes it to get to the break. You'd want to kill them...a lot.

The condition that causes a while loop to stop iterating should always be clear from the while loop line of code itself without having to look elsewhere.

Phil has the "correct" solution, as it has a clear end condition right there in the while loop statement itself.

java.lang.ClassNotFoundException: org.springframework.web.context.ContextLoaderListener

You could try "Clean Tomcat Work Directory" or simply "Clean..". This supposed to discard all published state and republish from scratch.

How to create an exit message

I got here searching for a way to execute some code whenever the program ends.
Found this:

Kernel.at_exit { puts "sayonara" }
# do whatever
# [...]
# call #exit or #abort or just let the program end
# calling #exit! will skip the call

Called multiple times will register multiple handlers.

What is the difference between "Rollback..." and "Back Out Submitted Changelist #####" in Perforce P4V

Both of these operations restore a set of files to a previous state and are essentially faster, safer ways of undoing mistakes than using the p4 obliterate command (and you don't need admin access to use them).

In the case of "Rollback...", this could be any number of files, even an entire depot. You can tell it to rollback to a specific revision, changelist, or label. The files are restored to the state they were in at the time of creation of that revision, changelist, or label.

In the case of "Back Out Submitted Changelist #####", the restore operation is restricted to the files that were submitted in changelist #####. Those files are restored to the state they were in before you submitted that changelist, provided no changes have been made to those files since. If subsequent changes have been made to any of those files, Perforce will tell you that those files are now out of date. You will have to sync to the head revision and then resolve the differences. This way you don't inadvertently clobber any changes that you actually want to keep.

Both operations work by essentially submitting old revisions as new revisions. When you perform a "Rollback...", you are restoring the files to the state they were in at a specific point in time, regardless of what has happened to them since. When you perform a "Back out...", you are attempting to undo the changes you made at a specific point in time, while maintaining the changes that have occurred since.

pythonic way to do something N times without an index variable?

I just use for _ in range(n), it's straight to the point. It's going to generate the entire list for huge numbers in Python 2, but if you're using Python 3 it's not a problem.

Retrieve all values from HashMap keys in an ArrayList Java

Suppose I have Hashmap with key datatype as KeyDataType and value datatype as ValueDataType

HashMap<KeyDataType,ValueDataType> list;

Add all items you needed to it. Now you can retrive all hashmap keys to a list by.

KeyDataType[] mKeys;
mKeys=list.keySet().toArray(new KeyDataType[list.size()]);

So, now you got your all keys in an array mkeys[]

you can now retrieve any value by calling

 list.get(mkeys[position]);

Numpy, multiply array with scalar

Using .multiply() (ufunc multiply)

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

np.multiply(a_1,b)
# array([2., 4., 6.])
np.multiply(a_2,b)
# array([[2., 4.],[6., 8.]])

What's the difference between a Python module and a Python package?

A module is a single file (or files) that are imported under one import and used. e.g.

import my_module

A package is a collection of modules in directories that give a package hierarchy.

from my_package.timing.danger.internets import function_of_love

Documentation for modules

Introduction to packages

Check if a given key already exists in a dictionary

Python 2 only: (and python 2.7 supports `in` already)

you can use the has_key() method:

if dict.has_key('xyz')==1:
    #update the value for the key
else:
    pass

Replacing instances of a character in a string

Strings in python are immutable, so you cannot treat them as a list and assign to indices.

Use .replace() instead:

line = line.replace(';', ':')

If you need to replace only certain semicolons, you'll need to be more specific. You could use slicing to isolate the section of the string to replace in:

line = line[:10].replace(';', ':') + line[10:]

That'll replace all semi-colons in the first 10 characters of the string.

Why is $$ returning the same id as the parent process?

You can use one of the following.

  • $! is the PID of the last backgrounded process.
  • kill -0 $PID checks whether it's still running.
  • $$ is the PID of the current shell.

programmatically add column & rows to WPF Datagrid

try this , it works 100 % : add columns and rows programatically : you need to create item class at first :

public class Item
        {
            public int Num { get; set; }
            public string Start { get; set; }
            public string Finich { get; set; }
        }

        private void generate_columns()
        {
            DataGridTextColumn c1 = new DataGridTextColumn();
            c1.Header = "Num";
            c1.Binding = new Binding("Num");
            c1.Width = 110;
            dataGrid1.Columns.Add(c1);
            DataGridTextColumn c2 = new DataGridTextColumn();
            c2.Header = "Start";
            c2.Width = 110;
            c2.Binding = new Binding("Start");
            dataGrid1.Columns.Add(c2);
            DataGridTextColumn c3 = new DataGridTextColumn();
            c3.Header = "Finich";
            c3.Width = 110;
            c3.Binding = new Binding("Finich");
            dataGrid1.Columns.Add(c3);

            dataGrid1.Items.Add(new Item() { Num = 1, Start = "2012, 8, 15", Finich = "2012, 9, 15" });
            dataGrid1.Items.Add(new Item() { Num = 2, Start = "2012, 12, 15", Finich = "2013, 2, 1" });
            dataGrid1.Items.Add(new Item() { Num = 3, Start = "2012, 8, 1", Finich = "2012, 11, 15" });

        }

How to avoid precompiled headers

The .cpp file is configured to use precompiled header, therefore it must be included first (before iostream). For Visual Studio, it's name is usually "stdafx.h".

If there are no stdafx* files in your project, you need to go to this file's options and set it as “Not using precompiled headers”.

Why use pip over easy_install?

Many of the answers here are out of date for 2015 (although the initially accepted one from Daniel Roseman is not). Here's the current state of things:

  • Binary packages are now distributed as wheels (.whl files)—not just on PyPI, but in third-party repositories like Christoph Gohlke's Extension Packages for Windows. pip can handle wheels; easy_install cannot.
  • Virtual environments (which come built-in with 3.4, or can be added to 2.6+/3.1+ with virtualenv) have become a very important and prominent tool (and recommended in the official docs); they include pip out of the box, but don't even work properly with easy_install.
  • The distribute package that included easy_install is no longer maintained. Its improvements over setuptools got merged back into setuptools. Trying to install distribute will just install setuptools instead.
  • easy_install itself is only quasi-maintained.
  • All of the cases where pip used to be inferior to easy_install—installing from an unpacked source tree, from a DVCS repo, etc.—are long-gone; you can pip install ., pip install git+https://.
  • pip comes with the official Python 2.7 and 3.4+ packages from python.org, and a pip bootstrap is included by default if you build from source.
  • The various incomplete bits of documentation on installing, using, and building packages have been replaced by the Python Packaging User Guide. Python's own documentation on Installing Python Modules now defers to this user guide, and explicitly calls out pip as "the preferred installer program".
  • Other new features have been added to pip over the years that will never be in easy_install. For example, pip makes it easy to clone your site-packages by building a requirements file and then installing it with a single command on each side. Or to convert your requirements file to a local repo to use for in-house development. And so on.

The only good reason that I know of to use easy_install in 2015 is the special case of using Apple's pre-installed Python versions with OS X 10.5-10.8. Since 10.5, Apple has included easy_install, but as of 10.10 they still don't include pip. With 10.9+, you should still just use get-pip.py, but for 10.5-10.8, this has some problems, so it's easier to sudo easy_install pip. (In general, easy_install pip is a bad idea; it's only for OS X 10.5-10.8 that you want to do this.) Also, 10.5-10.8 include readline in a way that easy_install knows how to kludge around but pip doesn't, so you also want to sudo easy_install readline if you want to upgrade that.

Python 3 - Encode/Decode vs Bytes/Str

To add to add to the previous answer, there is even a fourth way that can be used

import codecs
encoded4 = codecs.encode(original, 'utf-8')
print(encoded4)

Refresh (reload) a page once using jQuery?

You don't have a jQuery refresh function, because this is JavaScript basics.

Try this:

<body onload="if (location.href.indexOf('reload')==-1) location.replace(location.href+'?reload');">

Count if two criteria match - EXCEL formula

Add the sheet name infront of the cell, e.g.:

=COUNTIFS(stock!A:A,"M",stock!C:C,"Yes")

Assumes the sheet name is "stock"

Best practices for catching and re-throwing .NET exceptions

You may also use:

try
{
// Dangerous code
}
finally
{
// clean up, or do nothing
}

And any exceptions thrown will bubble up to the next level that handles them.

Use the auto keyword in C++ STL

If you want a code that is readable by all programmers (c++, java, and others) use the original old form instead of cryptographic new features

atp::ta::DataDrawArrayInfo* ddai;
for(size_t i = 0; i < m_dataDraw->m_dataDrawArrayInfoList.size(); i++) {
    ddai = m_dataDraw->m_dataDrawArrayInfoList[i];
    //...
}

Force Java timezone as GMT/UTC

I would retrieve the time from the DB in a raw form (long timestamp or java's Date), and then use SimpleDateFormat to format it, or Calendar to manipulate it. In both cases you should set the timezone of the objects before using it.

See SimpleDateFormat.setTimeZone(..) and Calendar.setTimeZone(..) for details

Android Studio was unable to find a valid Jvm (Related to MAC OS)

  1. Install newest JDK (8u102 current)
  2. Set envirionment variable STUDIO_JDK (java_home outputs the Java home dir and sed strips two folders to get the jdk dir)

    launchctl setenv STUDIO_JDK `/usr/libexec/java_home -version 1.8 | sed 's/\/Contents\/Home//g'`

  3. Launch Android Studio like you would normally

Set STUDIO_JDK on every reboot

The above steps only works for the current session. Here is how to create a plist file in /Library/LaunchDaemons that runs the above command on every boot:

sudo defaults write /Library/LaunchDaemons/com.google.studiojdk Label STUDIO_JDK
sudo defaults write /Library/LaunchDaemons/com.google.studiojdk ProgramArguments -array /bin/launchctl setenv STUDIO_JDK `/usr/libexec/java_home | sed 's/\/Contents\/Home//g'`
sudo defaults write /Library/LaunchDaemons/com.google.studiojdk RunAtLoad -bool TRUE

Found out about the plist trick thanks to http://www.dowdandassociates.com/blog/content/howto-set-an-environment-variable-in-mac-os-x-launchd-plist/

Euclidean distance of two vectors

If you want to use less code, you can also use the norm in the stats package (the 'F' stands for Forbenius, which is the Euclidean norm):

norm(matrix(x1-x2), 'F')

While this may look a bit neater, it's not faster. Indeed, a quick test on very large vectors shows little difference, though so12311's method is slightly faster. We first define:

set.seed(1234)
x1 <- rnorm(300000000)
x2 <- rnorm(300000000)

Then testing for time yields the following:

> system.time(a<-sqrt(sum((x1-x2)^2)))
user  system elapsed 
1.02    0.12    1.18 
> system.time(b<-norm(matrix(x1-x2), 'F'))
user  system elapsed 
0.97    0.33    1.31 

How can I change an element's class with JavaScript?

This is easiest with a library like jQuery:

<input type="button" onClick="javascript:test_byid();" value="id='second'" />

<script>
function test_byid()
{
    $("#second").toggleClass("highlight");
}
</script>

Plot data in descending order as appears in data frame

You want reorder(). Here is an example with dummy data

set.seed(42)
df <- data.frame(Category = sample(LETTERS), Count = rpois(26, 6))

require("ggplot2")

p1 <- ggplot(df, aes(x = Category, y = Count)) +
         geom_bar(stat = "identity")

p2 <- ggplot(df, aes(x = reorder(Category, -Count), y = Count)) +
         geom_bar(stat = "identity")

require("gridExtra")
grid.arrange(arrangeGrob(p1, p2))

Giving:

enter image description here

Use reorder(Category, Count) to have Category ordered from low-high.

Rails has_many with alias name

You could do this two different ways. One is by using "as"

has_many :tasks, :as => :jobs

or

def jobs
     self.tasks
end

Obviously the first one would be the best way to handle it.

How do I protect Python code?

Use the same way to protect binary file of c/c++, that is, obfuscate each function body in executable or library binary file, insert an instruction "jump" at the begin of each function entry, jump to special function to restore obfuscated code. Byte-code is binary code of Python script, so

  • First compile python script to code object
  • Then iterate each code object, obfuscate co_code of each code object as the following
    0   JUMP_ABSOLUTE            n = 3 + len(bytecode)

    3
    ...
    ... Here it's obfuscated bytecode
    ...

    n   LOAD_GLOBAL              ? (__pyarmor__)
    n+3 CALL_FUNCTION            0
    n+6 POP_TOP
    n+7 JUMP_ABSOLUTE            0
  • Save obfuscated code object as .pyc or .pyo file

Those obfuscated file (.pyc or .pyo) can be used by normal python interpreter, when those code object is called first time

  • First op is JUMP_ABSOLUTE, it will jump to offset n

  • At offset n, the instruction is to call a PyCFunction. This function will restore those obfuscated bytecode between offset 3 and n, and put the original byte-code at offset 0. The obfuscated code can be got by the following code

        char *obfucated_bytecode;
        Py_ssize_t len;
        PyFrameObject* frame = PyEval_GetFrame();
        PyCodeObject *f_code = frame->f_code;
        PyObject *co_code = f_code->co_code;      
        PyBytes_AsStringAndSize(co_code, &obfucated_bytecode, &len)
    
  • After this function returns, the last instruction is to jump to offset 0. The really byte-code now is executed.

There is a tool Pyarmor to obfuscate python scripts by this way.

What is the difference between a Docker image and a container?

As many answers pointed this out: You build Dockerfile to get an image and you run image to get a container.

However, following steps helped me get a better feel for what Docker image and container are:

1) Build Dockerfile:

docker build -t my_image dir_with_dockerfile

2) Save the image to .tar file

docker save -o my_file.tar my_image_id

my_file.tar will store the image. Open it with tar -xvf my_file.tar, and you will get to see all the layers. If you dive deeper into each layer you can see what changes were added in each layer. (They should be pretty close to commands in the Dockerfile).

3) To take a look inside of a container, you can do:

sudo docker run -it my_image bash

and you can see that is very much like an OS.

Client to send SOAP request and receive response

So this is my final code after googling for 2 days on how to add a namespace and make soap request along with the SOAP envelope without adding proxy/Service Reference

class Request
{
    public static void Execute(string XML)
    {
        try
        {
            HttpWebRequest request = CreateWebRequest();
            XmlDocument soapEnvelopeXml = new XmlDocument();
            soapEnvelopeXml.LoadXml(AppendEnvelope(AddNamespace(XML)));

            using (Stream stream = request.GetRequestStream())
            {
                soapEnvelopeXml.Save(stream);
            }

            using (WebResponse response = request.GetResponse())
            {
                using (StreamReader rd = new StreamReader(response.GetResponseStream()))
                {
                    string soapResult = rd.ReadToEnd();
                    Console.WriteLine(soapResult);
                }
            }
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }
    }

    private static HttpWebRequest CreateWebRequest()
    {
        string ICMURL = System.Configuration.ConfigurationManager.AppSettings.Get("ICMUrl");
        HttpWebRequest webRequest = null;

        try
        {
            webRequest = (HttpWebRequest)WebRequest.Create(ICMURL);
            webRequest.Headers.Add(@"SOAP:Action");
            webRequest.ContentType = "text/xml;charset=\"utf-8\"";
            webRequest.Accept = "text/xml";
            webRequest.Method = "POST";
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }
        return webRequest;
    }

    private static string AddNamespace(string XML)
    {
        string result = string.Empty;
        try
        {

            XmlDocument xdoc = new XmlDocument();
            xdoc.LoadXml(XML);

            XmlElement temproot = xdoc.CreateElement("ws", "Request", "http://example.com/");
            temproot.InnerXml = xdoc.DocumentElement.InnerXml;
            result = temproot.OuterXml;

        }
        catch (Exception ex)
        {
            Console.WriteLine(ex);
        }

        return result;
    }

    private static string AppendEnvelope(string data)
    {
        string head= @"<soapenv:Envelope xmlns:soapenv=""http://schemas.xmlsoap.org/soap/envelope/"" ><soapenv:Header/><soapenv:Body>";
        string end = @"</soapenv:Body></soapenv:Envelope>";
        return head + data + end;
    }
}

VBA check if object is set

The (un)safe way to do this - if you are ok with not using option explicit - is...

Not TypeName(myObj) = "Empty"

This also handles the case if the object has not been declared. This is useful if you want to just comment out a declaration to switch off some behaviour...

Dim myObj as Object
Not TypeName(myObj) = "Empty"  '/ true, the object exists - TypeName is Object

'Dim myObj as Object
Not TypeName(myObj) = "Empty"  '/ false, the object has not been declared

This works because VBA will auto-instantiate an undeclared variable as an Empty Variant type. It eliminates the need for an auxiliary Boolean to manage the behaviour.

Synchronous request in Node.js

use sequenty.

sudo npm install sequenty

or

https://github.com/AndyShin/sequenty

very simple.

var sequenty = require('sequenty'); 

function f1(cb) // cb: callback by sequenty
{
  console.log("I'm f1");
  cb(); // please call this after finshed
}

function f2(cb)
{
  console.log("I'm f2");
  cb();
}

sequenty.run([f1, f2]);

also you can use a loop like this:

var f = [];
var queries = [ "select .. blah blah", "update blah blah", ...];

for (var i = 0; i < queries.length; i++)
{
  f[i] = function(cb, funcIndex) // sequenty gives you cb and funcIndex
  {
    db.query(queries[funcIndex], function(err, info)
    {
       cb(); // must be called
    });
  }
}

sequenty.run(f); // fire!

How to get ° character in a string in python?

Put this line at the top of your source

# -*- coding: utf-8 -*-

If your editor uses a different encoding, substitute for utf-8

Then you can include utf-8 characters directly in the source

Catch browser's "zoom" event in JavaScript

There's no way to actively detect if there's a zoom. I found a good entry here on how you can attempt to implement it.

I’ve found two ways of detecting the zoom level. One way to detect zoom level changes relies on the fact that percentage values are not zoomed. A percentage value is relative to the viewport width, and thus unaffected by page zoom. If you insert two elements, one with a position in percentages, and one with the same position in pixels, they’ll move apart when the page is zoomed. Find the ratio between the positions of both elements and you’ve got the zoom level. See test case. http://web.archive.org/web/20080723161031/http://novemberborn.net/javascript/page-zoom-ff3

You could also do it using the tools of the above post. The problem is you're more or less making educated guesses on whether or not the page has zoomed. This will work better in some browsers than other.

There's no way to tell if the page is zoomed if they load your page while zoomed.

'git' is not recognized as an internal or external command

That's because at the time of installation you have selected the default radio button to use "Git" with the "Git bash" only. If you would have chosen "Git and command line tool" than this would not be an issue.

  • Solution#1: as you have already installed Git tool, now navigate to the desired folder and then right click and use "Git bash here" to run your same command and it will run properly.
  • Solution#2: try installing again the Git-scm and select the proper choice.

How many characters can you store with 1 byte?

1 byte may hold 1 character. For Example: Refer Ascii values for each character & convert into binary. This is how it works.

enter image description here value 255 is stored as (11111111) base 2. Visit this link for knowing more about binary conversion. http://acc6.its.brooklyn.cuny.edu/~gurwitz/core5/nav2tool.html

Size of Tiny Int = 1 Byte ( -128 to 127)

Int = 4 Bytes (-2147483648 to 2147483647)

how to clear the screen in python

If you mean the screen where you have that interpreter prompt >>> you can do CTRL+L on Bash shell can help. Windows does not have equivalent. You can do

import os
os.system('cls')  # on windows

or

os.system('clear')  # on linux / os x

Excel VBA - Sum up a column

I have a label on my form receiving the sum of numbers from Column D in Sheet1. I am only interested in rows 2 to 50, you can use a row counter if your row count is dynamic. I have some blank entries as well in column D and they are ignored.

Me.lblRangeTotal = Application.WorksheetFunction.Sum(ThisWorkbook.Sheets("Sheet1").Range("D2:D50"))

How to conditionally take action if FINDSTR fails to find a string

I tried to get this working using FINDSTR, but for some reason my "debugging" command always output an error level of 0:

ECHO %ERRORLEVEL%

My workaround is to use Grep from Cygwin, which outputs the right errorlevel (it will give an errorlevel greater than 0) if a string is not found:

dir c:\*.tib >out 2>>&1
grep "1 File(s)" out
IF %ERRORLEVEL% NEQ 0 "Run other commands" ELSE "Run Errorlevel 0 commands"

Cygwin's grep will also output errorlevel 2 if the file is not found. Here's the hash from my version:

C:\temp\temp>grep --version grep (GNU grep) 2.4.2

C:\cygwin64\bin>md5sum grep.exe c0a50e9c731955628ab66235d10cea23 *grep.exe

C:\cygwin64\bin>sha1sum grep.exe ff43a335bbec71cfe99ce8d5cb4e7c1ecdb3db5c *grep.exe

How do I write a Python dictionary to a csv file?

You are using DictWriter.writerows() which expects a list of dicts, not a dict. You want DictWriter.writerow() to write a single row.

You will also want to use DictWriter.writeheader() if you want a header for you csv file.

You also might want to check out the with statement for opening files. It's not only more pythonic and readable but handles closing for you, even when exceptions occur.

Example with these changes made:

import csv

my_dict = {"test": 1, "testing": 2}

with open('mycsvfile.csv', 'w') as f:  # You will need 'wb' mode in Python 2.x
    w = csv.DictWriter(f, my_dict.keys())
    w.writeheader()
    w.writerow(my_dict)

Which produces:

test,testing
1,2

Can Selenium interact with an existing browser session?

I'm using Rails + Cucumber + Selenium Webdriver + PhantomJS, and I've been using a monkey-patched version of Selenium Webdriver, which keeps PhantomJS browser open between test runs. See this blog post: http://blog.sharetribe.com/2014/04/07/faster-cucumber-startup-keep-phantomjs-browser-open-between-tests/

See also my answer to this post: How do I execute a command on already opened browser from a ruby file

Why is AJAX returning HTTP status code 0?

I found another case where jquery gives you status code 0 -- if for some reason XMLHttpRequest is not defined, you'll get this error.

Obviously this won't normally happen on the web, but a bug in a nightly firefox build caused this to crop up in an add-on I was writing. :)

Downcasting in Java

Using your example, you could do:

public void doit(A a) {
    if(a instanceof B) {
        // needs to cast to B to access draw2 which isn't present in A
        // note that this is probably not a good OO-design, but that would
        // be out-of-scope for this discussion :)
        ((B)a).draw2();
    }
    a.draw();
}

Get specific ArrayList item

As many have already told you:

mainList.get(3);

Be sure to check the ArrayList Javadoc.

Also, be careful with the arrays indices: in Java, the first element is at index 0. So if you are trying to get the third element, your solution would be mainList.get(2);

How can I make my website's background transparent without making the content (images & text) transparent too?

I would agree with @evillinux, It would be best to make your background image semi transparent so it supports < ie8

The other suggestions of using another div are also a great option, and it's the way to go if you want to do this in css. For example if the site had such features as selecting your own background color. I would suggest using a filter for older IE. eg:

filter:Alpha(opacity=50)

How do I reset the scale/zoom of a web app on an orientation change on the iPhone?

I've been using this function in my project.

function changeViewPort(key, val) {
    var reg = new RegExp(key, "i"), oldval = document.querySelector('meta[name="viewport"]').content;
    var newval = reg.test(oldval) ? oldval.split(/,\s*/).map(function(v){ return reg.test(v) ? key+"="+val : v; }).join(", ") : oldval+= ", "+key+"="+val ;
    document.querySelector('meta[name="viewport"]').content = newval;
}

so just addEventListener:

if( /iPad|iPhone|iPod|Android/i.test(navigator.userAgent) ){
    window.addEventListener("orientationchange", function() { 
        changeViewPort("maximum-scale", 1);
        changeViewPort("maximum-scale", 10);
    }
}

"Insert if not exists" statement in SQLite

For a unique column, use this:

INSERT OR REPLACE INTO table () values();

For more information, see: sqlite.org/lang_insert

Bitwise and in place of modulus operator

First of all, it's actually not accurate to say that

x % 2 == x & 1

Simple counterexample: x = -1. In many languages, including Java, -1 % 2 == -1. That is, % is not necessarily the traditional mathematical definition of modulo. Java calls it the "remainder operator", for example.

With regards to bitwise optimization, only modulo powers of two can "easily" be done in bitwise arithmetics. Generally speaking, only modulo powers of base b can "easily" be done with base b representation of numbers.

In base 10, for example, for non-negative N, N mod 10^k is just taking the least significant k digits.

References

yum error "Cannot retrieve metalink for repository: epel. Please verify its path and try again" updating ContextBroker

Walkthrough Steps

Running the following command will update the repo to use HTTP rather than HTTPS:

sudo sed -i "s/mirrorlist=https/mirrorlist=http/" /etc/yum.repos.d/epel.repo

You should then be able to update with this command:

yum -y update

Can I replace groups in Java regex?

Sorry to beat a dead horse, but it is kind-of weird that no-one pointed this out - "Yes you can, but this is the opposite of how you use capturing groups in real life".

If you use Regex the way it is meant to be used, the solution is as simple as this:

"6 example input 4".replaceAll("(?:\\d)(.*)(?:\\d)", "number$11");

Or as rightfully pointed out by shmosel below,

"6 example input 4".replaceAll("\d(.*)\d", "number$11");

...since in your regex there is no good reason to group the decimals at all.

You don't usually use capturing groups on the parts of the string you want to discard, you use them on the part of the string you want to keep.

If you really want groups that you want to replace, what you probably want instead is a templating engine (e.g. moustache, ejs, StringTemplate, ...).


As an aside for the curious, even non-capturing groups in regexes are just there for the case that the regex engine needs them to recognize and skip variable text. For example, in

(?:abc)*(capture me)(?:bcd)*

you need them if your input can look either like "abcabccapture mebcdbcd" or "abccapture mebcd" or even just "capture me".

Or to put it the other way around: if the text is always the same, and you don't capture it, there is no reason to use groups at all.

How do you debug MySQL stored procedures?

Answer corresponding to this by @Brad Parks Not sure about the MySQL version, but mine was 5.6, hence a little bit tweaking works:

I created a function debug_msg which is function (not procedure) and returns text(no character limit) and then call the function as SELECT debug_msg(params) AS my_res_set, code as below:

CREATE DEFINER=`root`@`localhost` FUNCTION `debug_msg`(`enabled` INT(11), `msg` TEXT) RETURNS text CHARSET latin1
    READS SQL DATA
BEGIN
    IF enabled=1 THEN
    return concat('** DEBUG:', "** ", msg);
    END IF;
END

DELIMITER $$
CREATE DEFINER=`root`@`localhost` PROCEDURE `proc_func_call`(
 IN RegionID VARCHAR(20),
 IN RepCurrency INT(11),
 IN MGID INT(11),
 IN VNC VARCHAR(255)
)
BEGIN
    SET @enabled = TRUE;
    SET @mainQuery = "SELECT * FROM Users u";
    SELECT `debug_msg`(@enabled, @mainQuery) AS `debug_msg1`;
    SET @lastQuery = CONCAT(@mainQuery, " WHERE u.age>30);
    SELECT `debug_msg`(@enabled, @lastQuery) AS `debug_msg2`;
END $$
DELIMITER

How do you implement a re-try-catch?

Spring AOP and annotation based solution:

Usage (@RetryOperation is our custom annotation for the job):

@RetryOperation(retryCount = 1, waitSeconds = 10)
boolean someMethod() throws Exception {
}

We'll need two things to accomplish this: 1. an annotation interface, and 2. a spring aspect. Here's one way to implement these:

The Annotation Interface:

import java.lang.annotation.*;

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface RetryOperation {
    int retryCount();
    int waitSeconds();
}

The Spring Aspect:

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import java.lang.reflect.Method;

@Aspect @Component 
public class RetryAspect {

    private static final Logger LOGGER = LoggerFactory.getLogger(RetryAspect.class);

    @Around(value = "@annotation(RetryOperation)")
    public Object retryOperation(ProceedingJoinPoint joinPoint) throws Throwable {

        Object response = null;
        Method method = ((MethodSignature) joinPoint.getSignature()).getMethod();
        RetryOperation annotation = method.getAnnotation(RetryOperation.class);
        int retryCount = annotation.retryCount();
        int waitSeconds = annotation.waitSeconds();
        boolean successful = false;

        do {
            try {
                response = joinPoint.proceed();
                successful = true;
            } catch (Exception ex) {
                LOGGER.info("Operation failed, retries remaining: {}", retryCount);
                retryCount--;
                if (retryCount < 0) {
                    throw ex;
                }
                if (waitSeconds > 0) {
                    LOGGER.info("Waiting for {} second(s) before next retry", waitSeconds);
                    Thread.sleep(waitSeconds * 1000l);
                }
            }
        } while (!successful);

        return response;
    }
}

Difference between "@id/" and "@+id/" in Android

From the Developer Guide:

android:id="@+id/my_button"

The at-symbol (@) at the beginning of the string indicates that the XML parser should parse and expand the rest of the ID string and identify it as an ID resource. The plus-symbol (+) means that this is a new resource name that must be created and added to our resources (in the R.java file). There are a number of other ID resources that are offered by the Android framework. When referencing an Android resource ID, you do not need the plus-symbol, but must add the android package namespace, like so:

android:id="@android:id/empty"

How to delete cookies on an ASP.NET website

Response.Cookies["UserSettings"].Expires = DateTime.Now.AddDays(-1)

How to get file_get_contents() to work with HTTPS?

Just add two lines in your php.ini file.

extension=php_openssl.dll

allow_url_include = On

its working for me.

Printing with "\t" (tabs) does not result in aligned columns

You can use this example to handle your problem:

System.out.printf( "%-15s %15s %n", "name", "lastname");
System.out.printf( "%-15s %15s %n", "Bill", "Smith");

You can play with the "%" until you find the right alignment to satisfy your needs

How do I return multiple values from a function in C?

Option 1: Declare a struct with an int and string and return a struct variable.

struct foo {    
 int bar1;
 char bar2[MAX];
};

struct foo fun() {
 struct foo fooObj;
 ...
 return fooObj;
}

Option 2: You can pass one of the two via pointer and make changes to the actual parameter through the pointer and return the other as usual:

int fun(char **param) {
 int bar;
 ...
 strcpy(*param,"....");
 return bar;
}

or

 char* fun(int *param) {
 char *str = /* malloc suitably.*/
 ...
 strcpy(str,"....");
 *param = /* some value */
 return str;
}

Option 3: Similar to the option 2. You can pass both via pointer and return nothing from the function:

void fun(char **param1,int *param2) {
 strcpy(*param1,"....");
 *param2 = /* some calculated value */
}

How can I autoformat/indent C code in vim?

Maybe you can try the followings $indent -kr -i8 *.c

Hope it's useful for you!

Redirect pages in JSP?

Just define the target page in the action attribute of the <form> containing the submit button.

So, in page1.jsp:

<form action="page2.jsp">
    <input type="submit">
</form>

Unrelated to the problem, a JSP is not the best place to do business stuff, if you need to do any. Consider learning servlets.

How do I pass a value from a child back to the parent form?

The fastest and more flexible way to do that is passing the parent to the children from the constructor as below:

  1. Declare a property in the parent form:

    public string MyProperty {get; set;}

  2. Declare a property from the parent in child form:

    private ParentForm ParentProperty {get; set;}

  3. Write the child's constructor like this:

      public ChildForm(ParentForm parent){
          ParentProperty= parent;
      }
    
  4. Change the value of the parent property everywhere in the child form:

    ParentProperty.MyProperty = "New value";

It's done. the property MyProperty in the parent form is changed. With this solution, you can change multiple properties from the child form. So delicious, no?!

What does "Use of unassigned local variable" mean?

There are many paths through your code whereby your variables are not initialized, which is why the compiler complains.

Specifically, you are not validating the user input for creditPlan - if the user enters a value of anything else than "0","1","2" or "3", then none of the branches indicated will be executed (and creditPlan will not be defaulted to zero as per your user prompt).

As others have mentioned, the compiler error can be avoided by either a default initialization of all derived variables before the branches are checked, OR ensuring that at least one of the branches is executed (viz, mutual exclusivity of the branches, with a fall through else statement).

I would however like to point out other potential improvements:

  • Validate user input before you trust it for use in your code.
  • Model the parameters as a whole - there are several properties and calculations applicable to each plan.
  • Use more appropriate types for data. e.g. CreditPlan appears to have a finite domain and is better suited to an enumeration or Dictionary than a string. Financial data and percentages should always be modelled as decimal, not double to avoid rounding issues, and 'status' appears to be a boolean.
  • DRY up repetitive code. The calculation, monthlyCharge = balance * annualRate * (1/12)) is common to more than one branch. For maintenance reasons, do not duplicate this code.
  • Possibly more advanced, but note that Functions are now first class citizens of C#, so you can assign a function or lambda as a property, field or parameter!.

e.g. here is an alternative representation of your model:

    // Keep all Credit Plan parameters together in a model
    public class CreditPlan
    {
        public Func<decimal, decimal, decimal> MonthlyCharge { get; set; }
        public decimal AnnualRate { get; set; }
        public Func<bool, Decimal> LateFee { get; set; }
    }

    // DRY up repeated calculations
    static private decimal StandardMonthlyCharge(decimal balance, decimal annualRate)
    { 
       return balance * annualRate / 12;
    }

    public static Dictionary<int, CreditPlan> CreditPlans = new Dictionary<int, CreditPlan>
    {
        { 0, new CreditPlan
            {
                AnnualRate = .35M, 
                LateFee = _ => 0.0M, 
                MonthlyCharge = StandardMonthlyCharge
            }
        },
        { 1, new CreditPlan
            {
                AnnualRate = .30M, 
                LateFee = late => late ? 0 : 25.0M,
                MonthlyCharge = StandardMonthlyCharge
            }
        },
        { 2, new CreditPlan
            {
                AnnualRate = .20M, 
                LateFee = late => late ? 0 : 35.0M,
                MonthlyCharge = (balance, annualRate) => balance > 100 
                    ? balance * annualRate / 12
                    : 0
            }
        },
        { 3, new CreditPlan
            {
                AnnualRate = .15M, 
                LateFee = _ => 0.0M,
                MonthlyCharge = (balance, annualRate) => balance > 500 
                    ? (balance - 500) * annualRate / 12
                    : 0
            }
        }
    };

What to put in a python module docstring?

Think about somebody doing help(yourmodule) at the interactive interpreter's prompt — what do they want to know? (Other methods of extracting and displaying the information are roughly equivalent to help in terms of amount of information). So if you have in x.py:

"""This module does blah blah."""

class Blah(object):
  """This class does blah blah."""

then:

>>> import x; help(x)

shows:

Help on module x:

NAME
    x - This module does blah blah.

FILE
    /tmp/x.py

CLASSES
    __builtin__.object
        Blah

    class Blah(__builtin__.object)
     |  This class does blah blah.
     |  
     |  Data and other attributes defined here:
     |  
     |  __dict__ = <dictproxy object>
     |      dictionary for instance variables (if defined)
     |  
     |  __weakref__ = <attribute '__weakref__' of 'Blah' objects>
     |      list of weak references to the object (if defined)

As you see, the detailed information on the classes (and functions too, though I'm not showing one here) is already included from those components' docstrings; the module's own docstring should describe them very summarily (if at all) and rather concentrate on a concise summary of what the module as a whole can do for you, ideally with some doctested examples (just like functions and classes ideally should have doctested examples in their docstrings).

I don't see how metadata such as author name and copyright / license helps the module's user — it can rather go in comments, since it could help somebody considering whether or not to reuse or modify the module.

What exactly does numpy.exp() do?

It calculates ex for each x in your list where e is Euler's number (approximately 2.718). In other words, np.exp(range(5)) is similar to [math.e**x for x in range(5)].

Twig: in_array or similar possible within if statement?

Just to clear some things up here. The answer that was accepted does not do the same as PHP in_array.

To do the same as PHP in_array use following expression:

{% if myVar in myArray %}

If you want to negate this you should use this:

{% if myVar not in myArray %}

Pandas - How to flatten a hierarchical index in columns

To flatten a MultiIndex inside a chain of other DataFrame methods, define a function like this:

def flatten_index(df):
  df_copy = df.copy()
  df_copy.columns = ['_'.join(col).rstrip('_') for col in df_copy.columns.values]
  return df_copy.reset_index()

Then use the pipe method to apply this function in the chain of DataFrame methods, after groupby and agg but before any other methods in the chain:

my_df \
  .groupby('group') \
  .agg({'value': ['count']}) \
  .pipe(flatten_index) \
  .sort_values('value_count')

How do I get the day of week given a date?

import datetime
int(datetime.datetime.today().strftime('%w'))+1

this should give you your real day number - 1 = sunday, 2 = monday, etc...

Get name of property as a string

I had some difficulty using the solutions already suggested for my specific use case, but figured it out eventually. I don't think my specific case is worthy of a new question, so I am posting my solution here for reference. (This is very closely related to the question and provides a solution for anyone else with a similar case to mine).

The code I ended up with looks like this:

public class HideableControl<T>: Control where T: class
{
    private string _propertyName;
    private PropertyInfo _propertyInfo;

    public string PropertyName
    {
        get { return _propertyName; }
        set
        {
            _propertyName = value;
            _propertyInfo = typeof(T).GetProperty(value);
        }
    }

    protected override bool GetIsVisible(IRenderContext context)
    {
        if (_propertyInfo == null)
            return false;

        var model = context.Get<T>();

        if (model == null)
            return false;

        return (bool)_propertyInfo.GetValue(model, null);
    }

    protected void SetIsVisibleProperty(Expression<Func<T, bool>> propertyLambda)
    {
        var expression = propertyLambda.Body as MemberExpression;
        if (expression == null)
            throw new ArgumentException("You must pass a lambda of the form: 'vm => vm.Property'");

        PropertyName = expression.Member.Name;
    }
}

public interface ICompanyViewModel
{
    string CompanyName { get; }
    bool IsVisible { get; }
}

public class CompanyControl: HideableControl<ICompanyViewModel>
{
    public CompanyControl()
    {
        SetIsVisibleProperty(vm => vm.IsVisible);
    }
}

The important part for me is that in the CompanyControl class the compiler will only allow me to choose a boolean property of ICompanyViewModel which makes it easier for other developers to get it right.

The main difference between my solution and the accepted answer is that my class is generic and I only want to match properties from the generic type that are boolean.

How to make a <svg> element expand or contract to its parent container?

For your iphone You could use in your head balise :

"width=device-width"

Python: Passing variables between functions

return returns a value. It doesn't matter what name you gave to that value. Returning it just "passes it out" so that something else can use it. If you want to use it, you have to grab it from outside:

lst = defineAList()
useTheList(lst)

Returning list from inside defineAList doesn't mean "make it so the whole rest of the program can use that variable". It means "pass this variable out and give the rest of the program one chance to grab it and use it". You need to assign that value to something outside the function in order to make use of it. Also, because of this, there is no need to define your list ahead of time with list = []. Inside defineAList, you create a new list and return it; this list has no relationship to the one you defined with list = [] at the beginning.

Incidentally, I changed your variable name from list to lst. It's not a good idea to use list as a variable name because that is already the name of a built-in Python type. If you make your own variable called list, you won't be able to access the builtin one anymore.

How do I tell whether my IE is 64-bit? (For that matter, Java too?)

Normally, you run IE 32 bit.
However, on 64-bit versions of Windows, there is a separate link in the Start Menu to Internet Explorer (64 bit). There's no real reason to use it, though.

In Help, About, the 64-bit version of IE will say 64-bit Edition (just after the full version string).

The 32-bit and 64-bit versions of IE have separate addons lists (because 32-bit addons cannot be loaded in 64-bit IE, and vice-versa), so you should make sure that Java appears on both lists.

In general, you can tell whether a process is 32-bit or 64-bit by right-clicking the application in Task Manager and clicking Go To Process. 32-bit processes will end with *32.

In Java, how to find if first character in a string is upper case without regex

Don't forget to check whether the string is empty or null. If we forget checking null or empty then we would get NullPointerException or StringIndexOutOfBoundException if a given String is null or empty.

public class StartWithUpperCase{

        public static void main(String[] args){

            String str1 = ""; //StringIndexOfBoundException if 
                              //empty checking not handled
            String str2 = null; //NullPointerException if 
                                //null checking is not handled.
            String str3 = "Starts with upper case";
            String str4 = "starts with lower case";

            System.out.println(startWithUpperCase(str1)); //false
            System.out.println(startWithUpperCase(str2)); //false
            System.out.println(startWithUpperCase(str3)); //true
            System.out.println(startWithUpperCase(str4)); //false



        }

        public static boolean startWithUpperCase(String givenString){

            if(null == givenString || givenString.isEmpty() ) return false;
            else return (Character.isUpperCase( givenString.codePointAt(0) ) );
        }

    }

How to loop an object in React?

I highly suggest you to use an array instead of an object if you're doing react itteration, this is a syntax I use it ofen.

const rooms = this.state.array.map((e, i) =>(<div key={i}>{e}</div>))

To use the element, just place {rooms} in your jsx.

Where e=elements of the arrays and i=index of the element. Read more here. If your looking for itteration, this is the way to do it.

How to create a density plot in matplotlib?

Maybe try something like:

import matplotlib.pyplot as plt
import numpy
from scipy import stats
data = [1.5]*7 + [2.5]*2 + [3.5]*8 + [4.5]*3 + [5.5]*1 + [6.5]*8
density = stats.kde.gaussian_kde(data)
x = numpy.arange(0., 8, .1)
plt.plot(x, density(x))
plt.show()

You can easily replace gaussian_kde() by a different kernel density estimate.

Does Python have a package/module management system?

Since no one has mentioned pipenv here, I would like to describe my views why everyone should use it for managing python packages.

As @ColonelPanic mentioned there are several issues with the Python Package Index and with pip and virtualenv also.

Pipenv solves most of the issues with pip and provides additional features also.

Pipenv features

Pipenv is intended to replace pip and virtualenv, which means pipenv will automatically create a separate virtual environment for every project thus avoiding conflicts between different python versions/package versions for different projects.

  • Enables truly deterministic builds, while easily specifying only what you want.
  • Generates and checks file hashes for locked dependencies.
  • Automatically install required Pythons, if pyenv is available.
  • Automatically finds your project home, recursively, by looking for a Pipfile.
  • Automatically generates a Pipfile, if one doesn’t exist.
  • Automatically creates a virtualenv in a standard location.
  • Automatically adds/removes packages to a Pipfile when they are un/installed.
  • Automatically loads .env files, if they exist.

If you have worked on python projects before, you would realize these features make managing packages way easier.

Other Commands

  • check checks for security vulnerabilities and asserts that PEP 508 requirements are being met by the current environment. (which I think is a great feature especially after this - Malicious packages on PyPi)
  • graph will show you a dependency graph, of your installed dependencies.

You can read more about it here - Pipenv.

Installation

You can find the installation documentation here

P.S.: If you liked working with the Python Package requests , you would be pleased to know that pipenv is by the same developer Kenneth Reitz

What is the convention for word separator in Java package names?

Anyone can use underscore _ (its Okay)

No one should use hypen - (its Bad practice)

No one should use capital letters inside package names (Bad practice)

NOTE: Here "Bad Practice" is meant for technically you are allowed to use that, but conventionally its not in good manners to write.

Source: Naming a Package(docs.oracle)

Send email by using codeigniter library via localhost

$insert = $this->db->insert('email_notification', $data);
                $this->session->set_flashdata("msg", "<div class='alert alert-success'> Cafe has been added Successfully.</div>");

                //require ("plugins/mailer/PHPMailerAutoload.php");
                $mail = new PHPMailer;
                $mail->SMTPOptions = array(
                    'ssl' => array(
                    'verify_peer' => false,
                    'verify_peer_name' => false,
                    'allow_self_signed' => true,
                ),
                );

                $message="
                     Your Account Has beed created successfully by Admin:
                    Username: ".$this->input->post('username')." <br><br>
                    Email: ".$this->input->post('sender_email')." <br><br>
                    Regargs<br>
                    <div class='background-color:#666;color:#fff;padding:6px;
                    text-align:center;'>
                         Bookly Admin.
                    </div>
                ";
                $mail->isSMTP(); // Set mailer to use SMTP
                $mail->Host = 'smtp.gmail.com'; // Specify main and backup SMTP servers
                $mail->SMTPAuth = true; 
                $subject = "Hello  ".$this->input->post('username');
                $mail->SMTDebug=2;
                $email = $this->input->post('sender_email'); //this email is user email
                $from_label = "Account Creation";
                $mail->Username = 'your email'; // SMTP username
                $mail->Password = 'password'; // SMTP password
                $mail->SMTPSecure = 'ssl'; // Enable TLS encryption, `ssl` also accepted
                $mail->Port = 465;
                $mail->setFrom($from_label);
                $mail->addAddress($email, 'Bookly Admin');
                $mail->isHTML(true);
                $mail->Subject = $subject;
                $mail->Body = $message;
                $mail->AltBody = 'This is the body in plain text for non-HTML mail clients';
             if($mail->send()){

                  }

conflicting types error when compiling c program using gcc

You have to declare your functions before main()

(or declare the function prototypes before main())

As it is, the compiler sees my_print (my_string); in main() as a function declaration.

Move your functions above main() in the file, or put:

void my_print (char *);
void my_print2 (char *);

Above main() in the file.

Check if any type of files exist in a directory using BATCH script

For files in a directory, you can use things like:

if exist *.csv echo "csv file found"

or

if not exist *.csv goto nofile

Is there a C# case insensitive equals operator?

or

if (StringA.Equals(StringB, StringComparison.CurrentCultureIgnoreCase)) {

but you need to be sure that StringA is not null. So probably better tu use:

string.Equals(StringA , StringB, StringComparison.CurrentCultureIgnoreCase);

as John suggested

EDIT: corrected the bug

Could not load type 'System.Runtime.CompilerServices.ExtensionAttribute' from assembly 'mscorlib

Could not load type 'System.Runtime.CompilerServices.ExtensionAttribute' from assembly mscorlib

Yes, this technically can go wrong when you execute code on .NET 4.0 instead of .NET 4.5. The attribute was moved from System.Core.dll to mscorlib.dll in .NET 4.5. While that sounds like a rather nasty breaking change in a framework version that is supposed to be 100% compatible, a [TypeForwardedTo] attribute is supposed to make this difference unobservable.

As Murphy would have it, every well intended change like this has at least one failure mode that nobody thought of. This appears to go wrong when ILMerge was used to merge several assemblies into one and that tool was used incorrectly. A good feedback article that describes this breakage is here. It links to a blog post that describes the mistake. It is rather a long article, but if I interpret it correctly then the wrong ILMerge command line option causes this problem:

  /targetplatform:"v4,c:\windows\Microsoft.NET\Framework\v4.0.30319"

Which is incorrect. When you install 4.5 on the machine that builds the program then the assemblies in that directory are updated from 4.0 to 4.5 and are no longer suitable to target 4.0. Those assemblies really shouldn't be there anymore but were kept for compat reasons. The proper reference assemblies are the 4.0 reference assemblies, stored elsewhere:

  /targetplatform:"v4,C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.0"

So possible workarounds are to fall back to 4.0 on the build machine, install .NET 4.5 on the target machine and the real fix, to rebuild the project from the provided source code, fixing the ILMerge command.


Do note that this failure mode isn't exclusive to ILMerge, it is just a very common case. Any other scenario where these 4.5 assemblies are used as reference assemblies in a project that targets 4.0 is liable to fail the same way. Judging from other questions, another common failure mode is in build servers that were setup without using a valid VS license. And overlooking that the multi-targeting packs are a free download.

Using the reference assemblies in the c:\program files (x86) subdirectory is a rock hard requirement. Starting at .NET 4.0, already important to avoid accidentally taking a dependency on a class or method that was added in the 4.01, 4.02 and 4.03 releases. But absolutely essential now that 4.5 is released.

Run exe file with parameters in a batch file

Unless it's just a simplified example for the question, my advice is that drop the batch wrapper and schedule PHP directly, more specifically the php-win.exe program, which won't open unnecessary windows.

Program: c:\program files\php\php-win.exe
Arguments: D:\mydocs\mp\index.php param1 param2

Otherwise, just quote stuff as Andrew points out.


In older versions of Windows, you should be able to put everything in the single "Run" text box (as long as you quote everything that has spaces):

"c:\program files\php\php-win.exe" D:\mydocs\mp\index.php param1 param2

MySQL root password change

This is the updated answer for WAMP v3.0.6 and up

> UPDATE mysql.user 
> SET authentication_string=PASSWORD('MyNewPass') 
> WHERE user='root';

> FLUSH PRIVILEGES;

In MySQL version 5.7.x there is no more password field in the mysql table. It was replaced with authentication_string. (This is for the terminal/CLI)

UPDATE mysql.user SET authentication_string=PASSWORD('MyNewPass') WHERE user='root';

FLUSH PRIVILEGES;

(This if for PHPMyAdmin or any Mysql GUI)

InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately

The docs give a fair indicator of what's required., however requests allow us to skip a few steps:

You only need to install the security package extras (thanks @admdrew for pointing it out)

$ pip install requests[security]

or, install them directly:

$ pip install pyopenssl ndg-httpsclient pyasn1

Requests will then automatically inject pyopenssl into urllib3


If you're on ubuntu, you may run into trouble installing pyopenssl, you'll need these dependencies:

$ apt-get install libffi-dev libssl-dev

cout is not a member of std

add #include <iostream> to the start of io.cpp too.

Monitoring the Full Disclosure mailinglist

Two generic ways to do the same thing... I'm not aware of any specific open solutions to do this, but it'd be rather trivial to do.

You could write a daily or weekly cron/jenkins job to scrape the previous time period's email from the archive looking for your keyworkds/combinations. Sending a batch digest with what it finds, if anything.

But personally, I'd Setup a specific email account to subscribe to the various security lists you're interested in. Add a simple automated script to parse the new emails for various keywords or combinations of keywords, when it finds a match forward that email on to you/your team. Just be sure to keep the keywords list updated with new products you're using.

You could even do this with a gmail account and custom rules, which is what I currently do, but I have setup an internal inbox in the past with a simple python script to forward emails that were of interest.

Python: Binary To Decimal Conversion

You can use int casting which allows the base specification.

int(b, 2)  # Convert a binary string to a decimal int.

How do I read an image file using Python?

The word "read" is vague, but here is an example which reads a jpeg file using the Image class, and prints information about it.

from PIL import Image
jpgfile = Image.open("picture.jpg")

print(jpgfile.bits, jpgfile.size, jpgfile.format)

Remove shadow below actionbar

For Xamarin Developers, please use : SupportActionBar.Elevation = 0; for AppCompatActivity or ActionBar.Elevation = 0; for non-compat Activities

How to add a footer in ListView?

The activity in which you want to add listview footer and i have also generate an event on listview footer click.

  public class MainActivity extends Activity
{

        @Override
        protected void onCreate(Bundle savedInstanceState)
         {

            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);

            ListView  list_of_f = (ListView) findViewById(R.id.list_of_f);

            LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);

            View view = inflater.inflate(R.layout.web_view, null);  // i have open a webview on the listview footer

            RelativeLayout  layoutFooter = (RelativeLayout) view.findViewById(R.id.layoutFooter);

            list_of_f.addFooterView(view);

        }

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/bg" >

    <ImageView
        android:id="@+id/dept_nav"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="@drawable/dept_nav" />

    <ListView
        android:id="@+id/list_of_f"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_below="@+id/dept_nav"
        android:layout_margin="5dp"
        android:layout_marginTop="10dp"
        android:divider="@null"
        android:dividerHeight="0dp"
        android:listSelector="@android:color/transparent" >
    </ListView>

</RelativeLayout>

Access Https Rest Service using Spring RestTemplate

This is a solution with no deprecated class or method : (Java 8 approved)

CloseableHttpClient httpClient = HttpClients.custom().setSSLHostnameVerifier(new NoopHostnameVerifier()).build();

HttpComponentsClientHttpRequestFactory requestFactory = new HttpComponentsClientHttpRequestFactory();
requestFactory.setHttpClient(httpClient);

RestTemplate restTemplate = new RestTemplate(requestFactory);

Important information : Using NoopHostnameVerifier is a security risk

What is a stored procedure?

A stored procedure is mainly used to perform certain tasks on a database. For example

  • Get database result sets from some business logic on data.
  • Execute multiple database operations in a single call.
  • Used to migrate data from one table to another table.
  • Can be called for other programming languages, like Java.

Best way to get hostname with php

I am running PHP version 5.4 on shared hosting and both of these both successfully return the same results:

php_uname('n');

gethostname();

Call PHP function from jQuery?

Yes, this is definitely possible. You'll need to have the php function in a separate php file. Here's an example using $.post:

$.post( 
    'yourphpscript.php', // location of your php script
    { name: "bob", user_id: 1234 }, // any data you want to send to the script
    function( data ){  // a function to deal with the returned information

        $( 'body ').append( data );

    });

And then, in your php script, just echo the html you want. This is a simple example, but a good place to get started:

<?php
    echo '<div id="test">Hello, World!</div>';
?>

How to check whether particular port is open or closed on UNIX?

netstat -ano|grep 443|grep LISTEN

will tell you whether a process is listening on port 443 (you might have to replace LISTEN with a string in your language, though, depending on your system settings).

ASP.NET Web Site or ASP.NET Web Application?

Web applications require more memory, presumably because you have no choice but to compile into a single assembly. I just converted a large legacy site to a web application and have issues with running out of memory, both at compile time with the error message as below :

Unexpected error writing metadata to file '' -- 
Not enough storage is available to complete this operation. 

error, and at runtime with this error message as below :

Exception information: 
    Exception type: HttpException 
    Exception message: Exception of type 'System.OutOfMemoryException' was thrown.
   at System.Web.Compilation.BuildManager.ReportTopLevelCompilationException()

My recommendation for converting larger sites on memory-constrained legacy hardware is, to choose the option to revert back to the web site model. Even after an initial success problem might creep up later.

How to access a RowDataPacket object

I really don't see what is the big deal with this I mean look if a run my sp which is CALL ps_get_roles();. Yes I get back an ugly ass response from DB and stuff. Which is this one:


[
  [
    RowDataPacket {
      id: 1,
      role: 'Admin',
      created_at: '2019-12-19 16:03:46'
    },
    RowDataPacket {
      id: 2,
      role: 'Recruiter',
      created_at: '2019-12-19 16:03:46'
    },
    RowDataPacket {
      id: 3,
      role: 'Regular',
      created_at: '2019-12-19 16:03:46'
    }
  ],
  OkPacket {
    fieldCount: 0,
    affectedRows: 0,
    insertId: 0,
    serverStatus: 35,
    warningCount: 0,
    message: '',
    protocol41: true,
    changedRows: 0
  }
]

it is an array that kind of look like this:


rows[0] = [
    RowDataPacket {/* them table rows*/ },
    RowDataPacket { },
    RowDataPacket { }
];

rows[1] = OkPacket {
   /* them props */
}

but if I do an http response to index [0] of rows at the client I get:

[
  {"id":1,"role":"Admin","created_at":"2019-12-19 16:03:46"}, 
  {"id":2,"role":"Recruiter","created_at":"2019-12-19 16:03:46"},
  {"id":3,"role":"Regular","created_at":"2019-12-19 16:03:46"}
]

and I didnt have to do none of yow things

rows[0].map(row => {
   return console.log("row: ", {...row});
});

the output gets some like this:

row:  { id: 1, role: 'Admin', created_at: '2019-12-19 16:03:46' }
row:  { id: 2, role: 'Recruiter', created_at: '2019-12-19 16:03:46' }
row:  { id: 3, role: 'Regular', created_at: '2019-12-19 16:03:46' }

So you all is tripping for no reason. Or it also could be the fact that I'm running store procedures instead of regular querys, the response from query and sp is not the same.

Where do I put image files, css, js, etc. in Codeigniter?

I just wanted to add that the problem may be even simpler -

I've been scratching my head for hours with this problem - I have read all the solutions, nothing worked. Then I managed to check the actual file name.

I had "image.jpg.jpg" rather than "image.jpg".

If you use $ ls public/..path to image assets../ you can quickly check the file names.

Sounds stupid but I never thought to look at something so simple as file name given the all the technical advice here.

"Adaptive Server is unavailable or does not exist" error connecting to SQL Server from PHP

I had the same issue, my problem was that the firewall on the server wasn't open from the current ip address.

how can I Update top 100 records in sql server

Without an ORDER BY the whole idea of TOP doesn't make much sense. You need to have a consistent definition of which direction is "up" and which is "down" for the concept of top to be meaningful.

Nonetheless SQL Server allows it but doesn't guarantee a deterministic result.

The UPDATE TOP syntax in the accepted answer does not support an ORDER BY clause but it is possible to get deterministic semantics here by using a CTE or derived table to define the desired sort order as below.

;WITH CTE AS 
( 
SELECT TOP 100 * 
FROM T1 
ORDER BY F2 
) 
UPDATE CTE SET F1='foo'

How to change python version in anaconda spyder

If you want to keep python 3, you can follow these directions to create a python 2.7 environment, called py27.

Then you just need to activate py27:

$ conda activate py27

Then you can install spyder on this environment, e.g.:

$ conda install spyder

Then you can start spyder from the command line or navigate to 2.7 version of spyder.exe below the envs directory (e.g. C:\ProgramData\Anaconda3\envs\py27\Scripts)

What is useState() in React?

useState() is a React hook. Hooks make possible to use state and mutability inside function components.

While you can't use hooks inside classes you can wrap your class component with a function one and use hooks from it. This is a great tool for migrating components from class to function form. Here is a complete example:

For this example I will use a counter component. This is it:

_x000D_
_x000D_
class Hello extends React.Component {_x000D_
  constructor(props) {_x000D_
    super(props);_x000D_
    this.state = { count: props.count };_x000D_
  }_x000D_
  _x000D_
  inc() {_x000D_
    this.setState(prev => ({count: prev.count+1}));_x000D_
  }_x000D_
  _x000D_
  render() {_x000D_
    return <button onClick={() => this.inc()}>{this.state.count}</button>_x000D_
  }_x000D_
}_x000D_
_x000D_
ReactDOM.render(<Hello count={0}/>, document.getElementById('root'))
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>_x000D_
<div id='root'></div>
_x000D_
_x000D_
_x000D_

It is a simple class component with a count state, and state update is done by methods. This is very common pattern in class components. The first thing is to wrap it with a function component with just the same name, that delegate all its properties to the wrapped component. Also you need to render the wrapped component in the function return. Here it is:

_x000D_
_x000D_
function Hello(props) {_x000D_
  class Hello extends React.Component {_x000D_
    constructor(props) {_x000D_
      super(props);_x000D_
      this.state = { count: props.count };_x000D_
    }_x000D_
_x000D_
    inc() {_x000D_
      this.setState(prev => ({count: prev.count+1}));_x000D_
    }_x000D_
_x000D_
    render() {_x000D_
      return <button onClick={() => this.inc()}>{this.state.count}</button>_x000D_
    }_x000D_
  }_x000D_
  return <Hello {...props}/>_x000D_
}_x000D_
_x000D_
ReactDOM.render(<Hello count={0}/>, document.getElementById('root'))
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.6.3/umd/react.production.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.6.3/umd/react-dom.production.min.js"></script>_x000D_
<div id='root'></div>
_x000D_
_x000D_
_x000D_

This is exactly the same component, with the same behavior, same name and same properties. Now lets lift the counting state to the function component. This is how it goes:

_x000D_
_x000D_
function Hello(props) {_x000D_
  const [count, setCount] = React.useState(0);_x000D_
  class Hello extends React.Component {_x000D_
    constructor(props) {_x000D_
      super(props);_x000D_
      this.state = { count: props.count };_x000D_
    }_x000D_
_x000D_
    inc() {_x000D_
      this.setState(prev => ({count: prev.count+1}));_x000D_
    }_x000D_
_x000D_
    render() {_x000D_
      return <button onClick={() => setCount(count+1)}>{count}</button>_x000D_
    }_x000D_
  }_x000D_
  return <Hello {...props}/>_x000D_
}_x000D_
_x000D_
ReactDOM.render(<Hello count={0}/>, document.getElementById('root'))
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.6/umd/react.production.min.js" integrity="sha256-3vo65ZXn5pfsCfGM5H55X+SmwJHBlyNHPwRmWAPgJnM=" crossorigin="anonymous"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js" integrity="sha256-qVsF1ftL3vUq8RFOLwPnKimXOLo72xguDliIxeffHRc=" crossorigin="anonymous"></script>_x000D_
<div id='root'></div>
_x000D_
_x000D_
_x000D_

Note that the method inc is still there, it wont hurt anybody, in fact is dead code. This is the idea, just keep lifting state up. Once you finished you can remove the class component:

_x000D_
_x000D_
function Hello(props) {_x000D_
  const [count, setCount] = React.useState(0);_x000D_
_x000D_
  return <button onClick={() => setCount(count+1)}>{count}</button>;_x000D_
}_x000D_
_x000D_
ReactDOM.render(<Hello count={0}/>, document.getElementById('root'))
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/16.8.6/umd/react.production.min.js" integrity="sha256-3vo65ZXn5pfsCfGM5H55X+SmwJHBlyNHPwRmWAPgJnM=" crossorigin="anonymous"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/16.8.6/umd/react-dom.production.min.js" integrity="sha256-qVsF1ftL3vUq8RFOLwPnKimXOLo72xguDliIxeffHRc=" crossorigin="anonymous"></script>_x000D_
_x000D_
<div id='root'></div>
_x000D_
_x000D_
_x000D_

While this makes possible to use hooks inside class components, I would not recommend you to do so except if you migrating like I did in this example. Mixing function and class components will make state management a mess. I hope this helps

Best Regards

C# Java HashMap equivalent

Check out the documentation on MSDN for the Hashtable class.

Represents a collection of key-and-value pairs that are organized based on the hash code of the key.

Also, keep in mind that this is not thread-safe.

if arguments is equal to this string, define a variable like this string

It seems that you are looking to parse commandline arguments into your bash script. I have searched for this recently myself. I came across the following which I think will assist you in parsing the arguments:

http://rsalveti.wordpress.com/2007/04/03/bash-parsing-arguments-with-getopts/

I added the snippet below as a tl;dr

#using : after a switch variable means it requires some input (ie, t: requires something after t to validate while h requires nothing.
while getopts “ht:r:p:v” OPTION
do
     case $OPTION in
         h)
             usage
             exit 1
             ;;
         t)
             TEST=$OPTARG
             ;;
         r)
             SERVER=$OPTARG
             ;;
         p)
             PASSWD=$OPTARG
             ;;
         v)
             VERBOSE=1
             ;;
         ?)
             usage
             exit
             ;;
     esac
done

if [[ -z $TEST ]] || [[ -z $SERVER ]] || [[ -z $PASSWD ]]
then
     usage
     exit 1
fi

./script.sh -t test -r server -p password -v

Automatically resize images with browser size using CSS

This may be too simplistic of an answer (I am still new here), but what I have done in the past to remedy this situation is figured out the percentage of the screen I would like the image to take up. For example, there is one webpage I am working on where the logo must take up 30% of the screen size to look best. I played around and finally tried this code and it has worked for me thus far:

img {
width:30%;
height:auto;
}

That being said, this will change all of your images to be 30% of the screen size at all times. To get around this issue, simply make this a class and apply it to the image that you desire to be at 30% directly. Here is an example of the code I wrote to accomplish this on the aforementioned site:

the CSS portion:

.logo {
position:absolute;
right:25%;
top:0px;
width:30%;
height:auto;
}

the HTML portion:

<img src="logo_001_002.png" class="logo">

Alternatively, you could place ever image you hope to automatically resize into a div of its own and use the class tag option on each div (creating now class tags whenever needed), but I feel like that would cause a lot of extra work eventually. But, if the site calls for it: the site calls for it.

Hopefully this helps. Have a great day!

Handler "ExtensionlessUrlHandler-Integrated-4.0" has a bad module "ManagedPipelineHandler" in its module list

I know this is an oldie, but thought I might add some value. For those of us running Server Core outside of a domain (domain members can just run Server Manager remotely to add/remove features/roles), you have to resort to command lines.

Powershell users can type "Install-WindowsFeature Web-Asp-Net45"

That should be equivalent to using server manager.

What is a superfast way to read large files line-by-line in VBA?

With that code you load the file in memory (as a big string) and then you read that string line by line.

By using Mid$() and InStr() you actually read the "file" twice but since it's in memory, there is no problem.
I don't know if VB's String has a length limit (probably not) but if the text files are hundreds of megabyte in size it's likely to see a performance drop, due to virtual memory usage.

How do I run a bat file in the background from another bat file?

Other than foreground/background term. Another way to hide running window is via vbscript, if is is still available in your system.

DIM objShell
set objShell=wscript.createObject("wscript.shell")
iReturn=objShell.Run("yourcommand.exe", 0, TRUE)

name it as sth.vbs and call it from bat, put in sheduled task, etc. PersonallyI'll disable vbs with no haste at any Windows system I manage :)

toBe(true) vs toBeTruthy() vs toBeTrue()

As you read through the examples below, just keep in mind this difference

true === true // true
"string" === true // false
1 === true // false
{} === true // false

But

Boolean("string") === true // true
Boolean(1) === true // true
Boolean({}) === true // true

1. expect(statement).toBe(true)

Assertion passes when the statement passed to expect() evaluates to true

expect(true).toBe(true) // pass
expect("123" === "123").toBe(true) // pass

In all other cases cases it would fail

expect("string").toBe(true) // fail
expect(1).toBe(true); // fail
expect({}).toBe(true) // fail

Even though all of these statements would evaluate to true when doing Boolean():

So you can think of it as 'strict' comparison

2. expect(statement).toBeTrue()

This one does exactly the same type of comparison as .toBe(true), but was introduced in Jasmine recently in version 3.5.0 on Sep 20, 2019

3. expect(statement).toBeTruthy()

toBeTruthy on the other hand, evaluates the output of the statement into boolean first and then does comparison

expect(false).toBeTruthy() // fail
expect(null).toBeTruthy() // fail
expect(undefined).toBeTruthy() // fail
expect(NaN).toBeTruthy() // fail
expect("").toBeTruthy() // fail
expect(0).toBeTruthy() // fail

And IN ALL OTHER CASES it would pass, for example

expect("string").toBeTruthy() // pass
expect(1).toBeTruthy() // pass
expect({}).toBeTruthy() // pass

Does "git fetch --tags" include "git fetch"?

Note: this answer is only valid for git v1.8 and older.

Most of this has been said in the other answers and comments, but here's a concise explanation:

  • git fetch fetches all branch heads (or all specified by the remote.fetch config option), all commits necessary for them, and all tags which are reachable from these branches. In most cases, all tags are reachable in this way.
  • git fetch --tags fetches all tags, all commits necessary for them. It will not update branch heads, even if they are reachable from the tags which were fetched.

Summary: If you really want to be totally up to date, using only fetch, you must do both.

It's also not "twice as slow" unless you mean in terms of typing on the command-line, in which case aliases solve your problem. There is essentially no overhead in making the two requests, since they are asking for different information.

How do I use a char as the case in a switch-case?

public class SwitCase {
    public static void main (String[] args){
        String hello = JOptionPane.showInputDialog("Input a letter: ");
        char hi = hello.charAt(0); //get the first char.
        switch(hi){
            case 'a': System.out.println("a");
        }
    }   
}

How do I split a string in Rust?

split returns an Iterator, which you can convert into a Vec using collect: split_line.collect::<Vec<_>>(). Going through an iterator instead of returning a Vec directly has several advantages:

  • split is lazy. This means that it won't really split the line until you need it. That way it won't waste time splitting the whole string if you only need the first few values: split_line.take(2).collect::<Vec<_>>(), or even if you need only the first value that can be converted to an integer: split_line.filter_map(|x| x.parse::<i32>().ok()).next(). This last example won't waste time attempting to process the "23.0" but will stop processing immediately once it finds the "1".
  • split makes no assumption on the way you want to store the result. You can use a Vec, but you can also use anything that implements FromIterator<&str>, for example a LinkedList or a VecDeque, or any custom type that implements FromIterator<&str>.

NSInternalInconsistencyException', reason: 'Could not load NIB in bundle: 'NSBundle

Well, I think the error says that it can't find a nib file named "RootViewController" in your project.

You are writing these lines of code,

self.viewController = [[RootViewController alloc]      initWithNibName:@"RootViewController_iPhone.xib" bundle:nil];

self.viewController = [[RootViewController alloc] initWithNibName:@"RootViewController_iPad.xib" bundle:nil];

At the same time you are asking it to load a nib file named "RootviewController"..!! Where is it..? Do you have a xib file named "Rootviewcontroller"..?

Bootstrap Accordion button toggle "data-parent" not working

Here is a (hopefully) universal patch I developed to fix this problem for BootStrap V3. No special requirements other than plugging in the script.

$(':not(.panel) > [data-toggle="collapse"][data-parent]').click(function() {
    var parent = $(this).data('parent');
    var items = $('[data-toggle="collapse"][data-parent="' + parent + '"]').not(this);
    items.each(function() {
        var target = $(this).data('target') || '#' + $(this).prop('href').split('#')[1];
        $(target).filter('.in').collapse('hide');
    });
});

EDIT: Below is a simplified answer which still meets my needs, and I'm now using a delegated click handler:

$(document.body).on('click', ':not(.panel) > [data-toggle="collapse"][data-parent]', function() {
    var parent = $(this).data('parent');
    var target = $(this).data('target') || $(this).prop('hash');
    $(parent).find('.collapse.in').not(target).collapse('hide');
});

How do I add python3 kernel to jupyter (IPython)

This answer explains how to create a Python 3, Jupyter 1, and ipykernel 5 workflow with Poetry dependency management. Poetry makes creating a virtual environment for Jupyter notebooks easy. I strongly recommend against running python3 commands. Python workflows that install global dependencies set you up for dependency hell.

Here's a summary of the clean, reliable Poetry workflow:

  • Install the dependencies with poetry add pandas jupyter ipykernel
  • Open a shell within the virtual environment with poetry shell
  • Open the Jupyter notebook with access to all the virtual environment dependencies with jupyter notebook

This blog discusses the workflow in more detail. There are clean Conda workflows as well. Watch out for a lot of the answers in this thread - they'll set you down a path that'll cause a lot of pain & suffering.