Programs & Examples On #Variable expansion

Evaluating or expanding a variable to get its value. Depending on the language, a variable may be expanded one or more times.

Linux Process States

While waiting for read() or write() to/from a file descriptor return, the process will be put in a special kind of sleep, known as "D" or "Disk Sleep". This is special, because the process can not be killed or interrupted while in such a state. A process waiting for a return from ioctl() would also be put to sleep in this manner.

An exception to this is when a file (such as a terminal or other character device) is opened in O_NONBLOCK mode, passed when its assumed that a device (such as a modem) will need time to initialize. However, you indicated block devices in your question. Also, I have never tried an ioctl() that is likely to block on a fd opened in non blocking mode (at least not knowingly).

How another process is chosen depends entirely on the scheduler you are using, as well as what other processes might have done to modify their weights within that scheduler.

Some user space programs under certain circumstances have been known to remain in this state forever, until rebooted. These are typically grouped in with other "zombies", but the term would not be correct as they are not technically defunct.

React proptype array with shape

Yes, you need to use PropTypes.arrayOf instead of PropTypes.array in the code, you can do something like this:

import PropTypes from 'prop-types';

MyComponent.propTypes = {
  annotationRanges: PropTypes.arrayOf(
    PropTypes.shape({
      start: PropTypes.string.isRequired,
      end: PropTypes.number.isRequired
    }).isRequired
  ).isRequired
}

Also for more details about proptypes, visit Typechecking With PropTypes here

Bash foreach loop

xargs --arg-file inputfile cat

This will output the filename followed by the file's contents:

xargs --arg-file inputfile -I % sh -c "echo %; cat %"

How could I use requests in asyncio?

The answers above are still using the old Python 3.4 style coroutines. Here is what you would write if you got Python 3.5+.

aiohttp supports http proxy now

import aiohttp
import asyncio

async def fetch(session, url):
    async with session.get(url) as response:
        return await response.text()

async def main():
    urls = [
            'http://python.org',
            'https://google.com',
            'http://yifei.me'
        ]
    tasks = []
    async with aiohttp.ClientSession() as session:
        for url in urls:
            tasks.append(fetch(session, url))
        htmls = await asyncio.gather(*tasks)
        for html in htmls:
            print(html[:100])

if __name__ == '__main__':
    loop = asyncio.get_event_loop()
    loop.run_until_complete(main())

Is there a simple JavaScript slider?

script.aculo.us has a slider control that might be worth checking out.

How do you use youtube-dl to download live streams (that are live)?

Some websites with m3u streaming cannot be downloaded in a single youtube-dl step, you can try something like this :

$ URL=https://www.arte.tv/fr/videos/078132-001-A/cosmos-une-odyssee-a-travers-l-univers/
$ youtube-dl -F $URL | grep m3u
HLS_XQ_2     m3u8       1280x720   VA-STA, Allemand 2200k 
HLS_XQ_1     m3u8       1280x720   VF-STF, Français 2200k 
$ CHOSEN_FORMAT=HLS_XQ_1
$ youtube-dl -F "$(youtube-dl -gf $CHOSEN_FORMAT)"
[generic] master: Requesting header
[generic] master: Downloading webpage
[generic] master: Downloading m3u8 information
[info] Available formats for master:
format code  extension  resolution note
61           mp4        audio only   61k , mp4a.40.2
419          mp4        384x216     419k , avc1.66.30, mp4a.40.2
923          mp4        640x360     923k , avc1.77.30, mp4a.40.2
1737         mp4        720x406    1737k , avc1.77.30, mp4a.40.2
2521         mp4        1280x720   2521k , avc1.77.30, mp4a.40.2 (best)
$ youtube-dl --hls-prefer-native -f 1737 "$(youtube-dl -gf $CHOSEN_FORMAT $URL)" -o "$(youtube-dl -f $CHOSEN_FORMAT --get-filename $URL)"
[generic] master: Requesting header
[generic] master: Downloading webpage
[generic] master: Downloading m3u8 information
[hlsnative] Downloading m3u8 manifest
[hlsnative] Total fragments: 257
[download] Destination: Cosmos_une_odyssee_a_travers_l_univers__HLS_XQ_1__078132-001-A.mp4
[download]   0.9% of ~731.27MiB at 624.95KiB/s ETA 13:13
....

How to show row number in Access query like ROW_NUMBER in SQL

One way to do this with MS Access is with a subquery but it does not have anything like the same functionality:

SELECT a.ID, 
       a.AText, 
       (SELECT Count(ID) 
        FROM table1 b WHERE b.ID <= a.ID 
        AND b.AText Like "*a*") AS RowNo
FROM Table1 AS a
WHERE a.AText Like "*a*"
ORDER BY a.ID;

Creating your own header file in C

header files contain prototypes for functions you define in a .c or .cpp/.cxx file (depending if you're using c or c++). You want to place #ifndef/#defines around your .h code so that if you include the same .h twice in different parts of your programs, the prototypes are only included once.

client.h

#ifndef CLIENT_H
#define CLIENT_H

short socketConnect(char *host,unsigned short port,char *sendbuf,char *recievebuf, long rbufsize);


#endif /** CLIENT_H */

Then you'd implement the .h in a .c file like so:

client.c

#include "client.h"

short socketConnect(char *host,unsigned short port,char *sendbuf,char *recievebuf, long rbufsize) {
 short ret = -1;
 //some implementation here
 return ret;
}

How to count items in JSON data

You're close. A really simple solution is just to get the length from the 'run' objects returned. No need to bother with 'load' or 'loads':

len(data['result'][0]['run'])

Escape double quotes in parameter

I'm calling powershell from cmd, and passing quotes and neither escapes here worked. The grave accent worked to escape double quotes on this Win 10 surface pro.

>powershell.exe "echo la`"" >> test
>type test
la"

Below are outputs I got for other characters to escape a double quote:

la\
la^
la
la~

Using another quote to escape a quote resulted in no quotes. As you can see, the characters themselves got typed, but didn't escape the double quotes.

Counting number of occurrences in column?

Just adding some extra sorting if needed

=QUERY(A2:A,"select A, count(A) where A is not null group by A order by count(A) DESC label A 'Name', count(A) 'Count'",-1)

enter image description here

Convert string to nullable type (int, double, etc...)

Let's add one more similar solution to the stack. This one also parses enums, and it looks nice. Very safe.

/// <summary>
    /// <para>More convenient than using T.TryParse(string, out T). 
    /// Works with primitive types, structs, and enums.
    /// Tries to parse the string to an instance of the type specified.
    /// If the input cannot be parsed, null will be returned.
    /// </para>
    /// <para>
    /// If the value of the caller is null, null will be returned.
    /// So if you have "string s = null;" and then you try "s.ToNullable...",
    /// null will be returned. No null exception will be thrown. 
    /// </para>
    /// <author>Contributed by Taylor Love (Pangamma)</author>
    /// </summary>
    /// <typeparam name="T"></typeparam>
    /// <param name="p_self"></param>
    /// <returns></returns>
    public static T? ToNullable<T>(this string p_self) where T : struct
    {
        if (!string.IsNullOrEmpty(p_self))
        {
            var converter = System.ComponentModel.TypeDescriptor.GetConverter(typeof(T));
            if (converter.IsValid(p_self)) return (T)converter.ConvertFromString(p_self);
            if (typeof(T).IsEnum) { T t; if (Enum.TryParse<T>(p_self, out t)) return t;}
        }

        return null;
    }

https://github.com/Pangamma/PangammaUtilities-CSharp/blob/master/PangammaUtilities/Extensions/ToNullableStringExtension.cs

Why is my Button text forced to ALL CAPS on Lollipop?

Using the android.support.v7.widget.AppCompatButton in the XML layout will allow you to avoid having to have a layout-21 or programmatically changing anything. Naturally this will also work with AppCompat v7 library.

<android.support.v7.widget.AppCompatButton
    android:id="@+id/btnOpenMainDemo"
    android:textAllCaps="false"
    style="@style/HGButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@string/btn_main_demo"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"/>

Hope this helps.

How can I define an interface for an array of objects with Typescript?

You don't need to use an indexer (since it a bit less typesafe). You have two options :

interface EnumServiceItem {
    id: number; label: string; key: any
}

interface EnumServiceItems extends Array<EnumServiceItem>{}


// Option A 
var result: EnumServiceItem[] = [
    { id: 0, label: 'CId', key: 'contentId' },
    { id: 1, label: 'Modified By', key: 'modifiedBy' },
    { id: 2, label: 'Modified Date', key: 'modified' },
    { id: 3, label: 'Status', key: 'contentStatusId' },
    { id: 4, label: 'Status > Type', key: ['contentStatusId', 'contentTypeId'] },
    { id: 5, label: 'Title', key: 'title' },
    { id: 6, label: 'Type', key: 'contentTypeId' },
    { id: 7, label: 'Type > Status', key: ['contentTypeId', 'contentStatusId'] }
];

// Option B
var result: EnumServiceItems = [
    { id: 0, label: 'CId', key: 'contentId' },
    { id: 1, label: 'Modified By', key: 'modifiedBy' },
    { id: 2, label: 'Modified Date', key: 'modified' },
    { id: 3, label: 'Status', key: 'contentStatusId' },
    { id: 4, label: 'Status > Type', key: ['contentStatusId', 'contentTypeId'] },
    { id: 5, label: 'Title', key: 'title' },
    { id: 6, label: 'Type', key: 'contentTypeId' },
    { id: 7, label: 'Type > Status', key: ['contentTypeId', 'contentStatusId'] }
]

Personally I recommend Option A (simpler migration when you are using classes not interfaces).

Remove columns from dataframe where ALL values are NA

Another options with purrr package:

library(dplyr)

df <- data.frame(a = NA,
                 b = seq(1:5), 
                 c = c(rep(1, 4), NA))

df %>% purrr::discard(~all(is.na(.)))
df %>% purrr::keep(~!all(is.na(.)))

How does the compilation/linking process work?

GCC compiles a C/C++ program into executable in 4 steps.

For example, gcc -o hello hello.c is carried out as follows:

1. Pre-processing

Preprocessing via the GNU C Preprocessor (cpp.exe), which includes the headers (#include) and expands the macros (#define).

cpp hello.c > hello.i

The resultant intermediate file "hello.i" contains the expanded source code.

2. Compilation

The compiler compiles the pre-processed source code into assembly code for a specific processor.

gcc -S hello.i

The -S option specifies to produce assembly code, instead of object code. The resultant assembly file is "hello.s".

3. Assembly

The assembler (as.exe) converts the assembly code into machine code in the object file "hello.o".

as -o hello.o hello.s

4. Linker

Finally, the linker (ld.exe) links the object code with the library code to produce an executable file "hello".

    ld -o hello hello.o ...libraries...

Access is denied when attaching a database

I had the same issue when attaching a database. It wasn't a SQL issue it was an account issue. Go to the panel control/User Account Control Settings/Set to "never notify". Finally,restart the computer and it worked for me.

jQuery: how do I animate a div rotation?

If you want just a jQuery option, this will work:

$(el).stop().animate(
  {rotation: 360},
  {
    duration: 500,
    step: function(now, fx) {
      $(this).css({"transform": "rotate("+now+"deg)"});
    }
  }
);

This works with jQuery 1.8, which takes care of CSS prefixing automatically. jQuery doesn't animate rotation so I'm putting the transform:rotate() in the custom step function. It might only work starting from 0.

Demo: http://jsfiddle.net/forresto/ShUgD/

IE9 and Mobile Safari 4 support CSS transforms but not CSS transitions, so I came up with this simple shim, using Modernizr feature testing:

if (Modernizr.csstransitions) {
  $(el).css({
    "transition": "all 500ms ease-in-out"
  });
}

$(el).click(function(){
  var rotateTo = 360;
  if (Modernizr.csstransitions) {
    $(el).css({"transform": "rotate("+rotateTo+"deg)"});
  } else {
    $(el).stop().animate(
      {rotation: rotateTo},
      {
        duration: 500,
        step: function(now, fx) {
          $(this).css({"transform": "rotate("+now+"deg)"});
        }
      }
    );
  }
});

The above will use CSS transitions when available.

How to find the date of a day of the week from a date using PHP?

<?php echo date("H:i", time()); ?>
<?php echo $days[date("l", time())] . date(", d.m.Y", time()); ?>

Simple, this should do the trick

How to run mvim (MacVim) from Terminal?

Here's what I did:

After building Macvim I copied mvim to one of my $PATH destinations (In this case I chose /usr/local/bin)

cp -v [MacVim_source_folder]/src/MacVim/mvim /usr/local/bin

Then when you invoke mvim it is now recognised but there is an annoying thing. It opens the visual MacVim window, not the one in terminal. To do that, you have to invoke

mvim -v

To make sure every time you call mvim you don't have to remember to add the '-v' you can create an alias:

alias mvim='mvim -v'

However, this alias will only persist for this session of the Terminal. To have this alias executed every time you open a Terminal window, you have to include it in your .profile The .profile should be in your home directory. If it's not, create it.

cd ~
mvim -v .profile

include the alias command in there and save it.

That's it.

Change keystore password from no password to a non blank password

On my system the password is 'changeit'. On blank if I hit enter then it complains about short password. Hope this helps

enter image description here

ExpressionChangedAfterItHasBeenCheckedError: Expression has changed after it was checked. Previous value: 'undefined'

you have to tell angular that you updated the content after ngAfterContentChecked you can import ChangeDetectorRef from @angular/core and call detectChanges

import {ChangeDetectorRef } from '@angular/core';

constructor( private cdref: ChangeDetectorRef ) {}


ngAfterContentChecked() {

this.sampleViewModel.DataContext = this.DataContext;
this.sampleViewModel.Position = this.Position;
this.cdref.detectChanges();

 }

C++ undefined reference to defined function

This could also happen if you are using CMake. If you have created a new class and you want to instantiate it, at the constructor call you will receive this error -even when the header and the cpp files are correct- if you have not modified CMakeLists.txt accordingly.

With CMake, every time you create a new class, before using it the header, the cpp files and any other compilable files (like Qt ui files) must be added to CMakeLists.txt and then re-run cmake . where CMakeLists.txt is stored.

For example, in this CMakeLists.txt file:

cmake_minimum_required(VERSION 2.8.11)

project(yourProject)

file(GLOB ImageFeatureDetector_SRC *.h *.cpp)

### Add your new files here ###
add_executable(yourProject YourNewClass.h YourNewClass.cpp otherNewFile.ui})

target_link_libraries(imagefeaturedetector ${SomeLibs})

If you are using the command file(GLOB yourProject_SRC *.h *.cpp) then you just need to re-run cmake . without modifying CMakeLists.txt.

How to fix: Error device not found with ADB.exe

I had this problem suddenly crop up in Windows 7 with my Nexus One - somehow the USB drivers had been uninstalled. I ran android-sdk/SDK Manager.exe, checked Extras/Google USB Driver and installed it. Then I unplugged the phone and plugged it back in, and ran "adb devices" to confirm the phone was attached.

This doesn't work for all phones, just the ones listed here: http://developer.android.com/sdk/win-usb.html

Does hosts file exist on the iPhone? How to change it?

This doesn't directly answer your question, but it does solve your problem...

What make of router do you have? Your router firmware may allow you to set DNS records for your local network. This is what I do with the Tomato firmware

How to set a Default Route (To an Area) in MVC

What I did to get this to work is the following:

  1. I created a default controller in the root/Controllers folder. I named my controller DefaultController.
  2. In the controller I added the following code:

    namespace MyNameSpace.Controllers {
    public class DefaultController : Controller {
        // GET: Default
        public ActionResult Index() {
            return RedirectToAction("Index", "ControllerName", new {area = "FolderName"});
        }
    } }
    
  3. In my RouterConfig.cs I added the following:

    routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new {controller = "Default", action = "Index", id = UrlParameter.Optional});
    

The trick behind all this is that I made a default constructor which will always be the startup controller every time my app starts. When it hits that default controller it will redirect to any controller I specify in the default Index Action. Which in my case is

www.myurl.com/FolderName/ControllerName

.

Why is there no tuple comprehension in Python?

Tuples cannot efficiently be appended like a list.

So a tuple comprehension would need to use a list internally and then convert to a tuple.

That would be the same as what you do now : tuple( [ comprehension ] )

$.focus() not working

Pro tip. If you want to turn on focus from the dev console then just open the console as a separate window from the options tab. The latest Firefox and Chrome supports this feature.

jQuery Dialog Box

if You want to change opacity for all dialog then change in jquery-ui.css

/* Overlays */
.ui-widget-overlay
{
    background: #5c5c5c url(images/ui-bg_flat_50_5c5c5c_40x100.png) 50% 50% repeat-x;
    opacity: .50;
    filter: Alpha(Opacity=80);
}

Can we rely on String.isEmpty for checking null condition on a String in Java?

I think the even shorter answer that you'll like is: StringUtils.isBlank(acct);

From the documentation: http://commons.apache.org/proper/commons-lang/javadocs/api-2.6/org/apache/commons/lang/StringUtils.html#isBlank%28java.lang.String%29

isBlank
public static boolean isBlank(String str)
Checks if a String is whitespace, empty ("") or null.

 StringUtils.isBlank(null)      = true
 StringUtils.isBlank("")        = true
 StringUtils.isBlank(" ")       = true
 StringUtils.isBlank("bob")     = false
 StringUtils.isBlank("  bob  ") = false
 
Parameters:
str - the String to check, may be null
Returns:
true if the String is null, empty or whitespace

The easiest way to transform collection to array?

If you use it more than once or in a loop, you could define a constant

public static final Foo[] FOO = new Foo[]{};

and do the conversion it like

Foo[] foos = fooCollection.toArray(FOO);

The toArray method will take the empty array to determine the correct type of the target array and create a new array for you.


Here's my proposal for the update:

Collection<Foo> foos = new ArrayList<Foo>();
Collection<Bar> temp = new ArrayList<Bar>();
for (Foo foo:foos) 
    temp.add(new Bar(foo));
Bar[] bars = temp.toArray(new Bar[]{});

C++ style cast from unsigned char * to const char *

char * and const unsigned char * are considered unrelated types. So you want to use reinterpret_cast.

But if you were going from const unsigned char* to a non const type you'd need to use const_cast first. reinterpret_cast cannot cast away a const or volatile qualification.

How to remove html special chars?

<?php
function strip_only($str, $tags, $stripContent = false) {
    $content = '';
    if(!is_array($tags)) {
        $tags = (strpos($str, '>') !== false
                 ? explode('>', str_replace('<', '', $tags))
                 : array($tags));
        if(end($tags) == '') array_pop($tags);
    }
    foreach($tags as $tag) {
        if ($stripContent)
             $content = '(.+</'.$tag.'[^>]*>|)';
         $str = preg_replace('#</?'.$tag.'[^>]*>'.$content.'#is', '', $str);
    }
    return $str;
}

$str = '<font color="red">red</font> text';
$tags = 'font';
$a = strip_only($str, $tags); // red text
$b = strip_only($str, $tags, true); // text
?> 

Get Table and Index storage size in sql server

with pages as (
    SELECT object_id, SUM (reserved_page_count) as reserved_pages, SUM (used_page_count) as used_pages,
            SUM (case 
                    when (index_id < 2) then (in_row_data_page_count + lob_used_page_count + row_overflow_used_page_count)
                    else lob_used_page_count + row_overflow_used_page_count
                 end) as pages
    FROM sys.dm_db_partition_stats
    group by object_id
), extra as (
    SELECT p.object_id, sum(reserved_page_count) as reserved_pages, sum(used_page_count) as used_pages
    FROM sys.dm_db_partition_stats p, sys.internal_tables it
    WHERE it.internal_type IN (202,204,211,212,213,214,215,216) AND p.object_id = it.object_id
    group by p.object_id
)
SELECT object_schema_name(p.object_id) + '.' + object_name(p.object_id) as TableName, (p.reserved_pages + isnull(e.reserved_pages, 0)) * 8 as reserved_kb,
        pages * 8 as data_kb,
        (CASE WHEN p.used_pages + isnull(e.used_pages, 0) > pages THEN (p.used_pages + isnull(e.used_pages, 0) - pages) ELSE 0 END) * 8 as index_kb,
        (CASE WHEN p.reserved_pages + isnull(e.reserved_pages, 0) > p.used_pages + isnull(e.used_pages, 0) THEN (p.reserved_pages + isnull(e.reserved_pages, 0) - p.used_pages + isnull(e.used_pages, 0)) else 0 end) * 8 as unused_kb
from pages p
left outer join extra e on p.object_id = e.object_id

Takes into account internal tables, such as those used for XML storage.

Edit: If you divide the data_kb and index_kb values by 1024.0, you will get the numbers you see in the GUI.

Apache 2.4 - Request exceeded the limit of 10 internal redirects due to probable configuration error

Solved this by adding following

RewriteCond %{ENV:REDIRECT_STATUS} 200 [OR]
 RewriteCond %{REQUEST_FILENAME} -f [OR]
 RewriteCond %{REQUEST_FILENAME} -d
 RewriteRule ^ - [L]

Simple int to char[] conversion

You can't truly do it in "standard" C, because the size of an int and of a char aren't fixed. Let's say you are using a compiler under Windows or Linux on an intel PC...

int i = 5;
char a = ((char*)&i)[0];
char b = ((char*)&i)[1];

Remember of endianness of your machine! And that int are "normally" 32 bits, so 4 chars!

But you probably meant "i want to stringify a number", so ignore this response :-)

Show special characters in Unix while using 'less' Command

In the same spirit as https://stackoverflow.com/a/6943976/7154924:

cat -A

-A, --show-all
       equivalent to -vET
-v, --show-nonprinting
       use ^ and M- notation, except for LFD and TAB
-E, --show-ends
       display $ at end of each line
-T, --show-tabs
       display TAB characters as ^I

Alternatively, or at the same time, you can pipe to tr to substitute arbitrary characters to the desired ones for display, before piping to a pager like less if desired.

VB.NET Inputbox - How to identify when the Cancel Button is pressed?

You can do it in a simpler way using the DialogResult.cancel method.

Eg:

Dim anInput as String = InputBox("Enter your pin")

If anInput <>"" then

   ' Do something
Elseif DialogResult.Cancel then

  Msgbox("You've canceled")
End if

Passing functions with arguments to another function in Python?

Here is a way to do it with a closure:

    def generate_add_mult_func(func):
        def function_generator(x):
            return reduce(func,range(1,x))
        return function_generator

    def add(x,y):
        return x+y

    def mult(x,y):
        return x*y

    adding=generate_add_mult_func(add)
    multiplying=generate_add_mult_func(mult)

    print adding(10)
    print multiplying(10)

XML to CSV Using XSLT

Here is a version with configurable parameters that you can set programmatically:

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:output method="text" encoding="utf-8" />

  <xsl:param name="delim" select="','" />
  <xsl:param name="quote" select="'&quot;'" />
  <xsl:param name="break" select="'&#xA;'" />

  <xsl:template match="/">
    <xsl:apply-templates select="projects/project" />
  </xsl:template>

  <xsl:template match="project">
    <xsl:apply-templates />
    <xsl:if test="following-sibling::*">
      <xsl:value-of select="$break" />
    </xsl:if>
  </xsl:template>

  <xsl:template match="*">
    <!-- remove normalize-space() if you want keep white-space at it is --> 
    <xsl:value-of select="concat($quote, normalize-space(), $quote)" />
    <xsl:if test="following-sibling::*">
      <xsl:value-of select="$delim" />
    </xsl:if>
  </xsl:template>

  <xsl:template match="text()" />
</xsl:stylesheet>

did you register the component correctly? For recursive components, make sure to provide the "name" option

This is very common error that we face while starting any Project Vue. I spent lot of time to search this error and finally found a Solution. Suppose i have component that is "table.vue",

i.e components/table.vue

In app.js

Vue.component('mytablecomp', require('./components/table.vue').default);

So in in your index.blade file call component as

<mytablecomp></mytablecomp>

Just you need to keep in mind that your component name is in small not in large or camel case. Then my above code will surely work for you.

Thanks

How to split string and push in array using jquery

var string = 'a,b,c,d',
    strx   = string.split(',');
    array  = [];

array = array.concat(strx);
// ["a","b","c","d"]

Pandas DataFrame Groupby two columns and get counts

Followed by @Andy's answer, you can do following to solve your second question:

In [56]: df.groupby(['col5','col2']).size().reset_index().groupby('col2')[[0]].max()
Out[56]: 
      0
col2   
A     3
B     2
C     1
D     3

how to drop database in sqlite?

You can drop tables by issuing an SQL Command as you would normally. If you want to drop the whole database you'll have to delete the file. You can delete the file located under

data/data/com.your.app.name/database/[databasefilename]

you can do this from the eclipse view called "FileBrowser" out of the "Android" Category for example. Or directly on your emulator or phone.

How to change DatePicker dialog color for Android 5.0

For Changing Year list item text color (SPECIFIC FOR ANDROID 5.0)

Just set certain text color in your date picker dialog style. For some reason setting flag yearListItemTextAppearance doesn't reflect any change on year list.

<item name="android:textColor">@android:color/black</item>

selecting rows with id from another table

SELECT terms.*
FROM terms JOIN terms_relation ON id=term_id
WHERE taxonomy='categ'

Fetch the row which has the Max value for a column

select VALUE from TABLE1 where TIME = 
   (select max(TIME) from TABLE1 where DATE= 
   (select max(DATE) from TABLE1 where CRITERIA=CRITERIA))

Check if a given key already exists in a dictionary

Using ternary operator:

message = "blah" if 'key1' in dict else "booh"
print(message)

Gradle: Execution failed for task ':processDebugManifest'

I had

tools:replace="android:allowBackup"

in my AndroidManifest.xml file.

I have got the exact information in merged manifest section.

enter image description here

After removing it the error got resolved.

How to push both key and value into an Array in Jquery

There are no keys in JavaScript arrays. Use objects for that purpose.

var obj = {};

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        obj[news.title] = news.link;
    });                      
});

// later:
$.each(obj, function (index, value) {
    alert( index + ' : ' + value );
});

In JavaScript, objects fulfill the role of associative arrays. Be aware that objects do not have a defined "sort order" when iterating them (see below).

However, In your case it is not really clear to me why you transfer data from the original object (data.news) at all. Why do you not simply pass a reference to that object around?


You can combine objects and arrays to achieve predictable iteration and key/value behavior:

var arr = [];

$.getJSON("displayjson.php",function (data) {
    $.each(data.news, function (i, news) {
        arr.push({
            title: news.title, 
            link:  news.link
        });
    });                      
});

// later:
$.each(arr, function (index, value) {
    alert( value.title + ' : ' + value.link );
});

Converting XDocument to XmlDocument and vice versa

If you need to convert the instance of System.Xml.Linq.XDocument into the instance of the System.Xml.XmlDocument this extension method will help you to do not lose the XML declaration in the resulting XmlDocument instance:

using System.Xml; 
using System.Xml.Linq;

namespace www.dimaka.com
{ 
    internal static class LinqHelper 
    { 
        public static XmlDocument ToXmlDocument(this XDocument xDocument) 
        { 
            var xmlDocument = new XmlDocument(); 
            using (var reader = xDocument.CreateReader()) 
            { 
                xmlDocument.Load(reader); 
            }

            var xDeclaration = xDocument.Declaration; 
            if (xDeclaration != null) 
            { 
                var xmlDeclaration = xmlDocument.CreateXmlDeclaration( 
                    xDeclaration.Version, 
                    xDeclaration.Encoding, 
                    xDeclaration.Standalone);

                xmlDocument.InsertBefore(xmlDeclaration, xmlDocument.FirstChild); 
            }

            return xmlDocument; 
        } 
    } 
}

Hope that helps!

How can I create a Java method that accepts a variable number of arguments?

Take a look at the Java guide on varargs.

You can create a method as shown below. Simply call System.out.printf instead of System.out.println(String.format(....

public static void print(String format, Object... args) {
    System.out.printf(format, args);
}

Alternatively, you can just use a static import if you want to type as little as possible. Then you don't have to create your own method:

import static java.lang.System.out;

out.printf("Numer of apples: %d", 10);

ReactJS - Add custom event listener to component

First off, custom events don't play well with React components natively. So you cant just say <div onMyCustomEvent={something}> in the render function, and have to think around the problem.

Secondly, after taking a peek at the documentation for the library you're using, the event is actually fired on document.body, so even if it did work, your event handler would never trigger.

Instead, inside componentDidMount somewhere in your application, you can listen to nv-enter by adding

document.body.addEventListener('nv-enter', function (event) {
    // logic
});

Then, inside the callback function, hit a function that changes the state of the component, or whatever you want to do.

Want to upgrade project from Angular v5 to Angular v6

Complete guide

-----------------With angular-cli--------------------------

1. Update CLI globally and locally

  1. Using NPM ( make sure that you have node version 8+ )

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

  2. Using Yarn

    yarn remove @angular/cli yarn global add @angular/cli yarn add @angular/cli

2.Update dependencies

ng update @angular/cli
ng update @angular/core
ng update @angular/material
ng update rxjs

Angular 6 now depends on TypeScript 2.7 and RxJS 6

Normally that would mean that you have to update your code everywhere RxJS imports and operators are used, but thankfully there’s a package that takes care of most of the heavy lifting:

npm i -g rxjs-tslint 

//or using yarn

yarn global add rxjs-tslint

Then you can run rxjs-5-to-6-migrate

rxjs-5-to-6-migrate -p src/tsconfig.app.json

finally remove rxjs-compat

npm uninstall rxjs-compat

// or using Yarn

yarn remove rxjs-compat

Refer to this link https://alligator.io/angular/angular-6/


-------------------Without angular-cli-------------------------

So you have to manually update your package.json file.

package.json screenshoot of upgrade packages

Then run

 npm update
 npm install --save rxjs-compat
 npm i -g rxjs-tslint
 rxjs-5-to-6-migrate -p src/tsconfig.app.json

Programmatically set image to UIImageView with Xcode 6.1/Swift

Since you have your bgImage assigned and linked as an IBOutlet, there is no need to initialize it as a UIImageView... instead all you need to do is set the image property like bgImage.image = UIImage(named: "afternoon"). After running this code, the image appeared fine since it was already assigned using the outlet.

enter image description here

However, if it wasn't an outlet and you didn't have it already connected to a UIImageView object on a storyboard/xib file, then you could so something like the following...

class ViewController: UIViewController {
    var bgImage: UIImageView?

    override func viewDidLoad() {
        super.viewDidLoad()

        var image: UIImage = UIImage(named: "afternoon")!
        bgImage = UIImageView(image: image)
        bgImage!.frame = CGRectMake(0,0,100,200)
        self.view.addSubview(bgImage!)
    }
}

Reading multiple Scanner inputs

If every input asks the same question, you should use a for loop and an array of inputs:

Scanner dd = new Scanner(System.in);
int[] vars = new int[3];

for(int i = 0; i < vars.length; i++) {
  System.out.println("Enter next var: ");
  vars[i] = dd.nextInt();
}

Or as Chip suggested, you can parse the input from one line:

Scanner in = new Scanner(System.in);
int[] vars = new int[3];

System.out.println("Enter "+vars.length+" vars: ");
for(int i = 0; i < vars.length; i++)
  vars[i] = in.nextInt();

You were on the right track, and what you did works. This is just a nicer and more flexible way of doing things.

Replacement for "rename" in dplyr

It is not listed as a function in dplyr (yet): http://cran.rstudio.org/web/packages/dplyr/dplyr.pdf

The function below works (almost) the same if you don't want to load both plyr and dplyr

rename <- function(dat, oldnames, newnames) {
  datnames <- colnames(dat)
  datnames[which(datnames %in% oldnames)] <- newnames
  colnames(dat) <- datnames
  dat
}

dat <- rename(mtcars,c("mpg","cyl"), c("mympg","mycyl"))
head(dat)

                  mympg mycyl disp  hp drat    wt  qsec vs am gear carb
Mazda RX4          21.0     6  160 110 3.90 2.620 16.46  0  1    4    4
Mazda RX4 Wag      21.0     6  160 110 3.90 2.875 17.02  0  1    4    4
Datsun 710         22.8     4  108  93 3.85 2.320 18.61  1  1    4    1
Hornet 4 Drive     21.4     6  258 110 3.08 3.215 19.44  1  0    3    1
Hornet Sportabout  18.7     8  360 175 3.15 3.440 17.02  0  0    3    2
Valiant            18.1     6  225 105 2.76 3.460 20.22  1  0    3    1

Edit: The comment by Romain produces the following (note that the changes function requires dplyr .1.1)

> dplyr:::changes(mtcars, dat)
Changed variables:
          old         new        
disp      0x108b4b0e0 0x108b4e370
hp        0x108b4b210 0x108b4e4a0
drat      0x108b4b340 0x108b4e5d0
wt        0x108b4b470 0x108b4e700
qsec      0x108b4b5a0 0x108b4e830
vs        0x108b4b6d0 0x108b4e960
am        0x108b4b800 0x108b4ea90
gear      0x108b4b930 0x108b4ebc0
carb      0x108b4ba60 0x108b4ecf0
mpg       0x1033ee7c0            
cyl       0x10331d3d0            
mympg                 0x108b4e110
mycyl                 0x108b4e240

Changed attributes:
          old         new        
names     0x10c100558 0x10c2ea3f0
row.names 0x108b4bb90 0x108b4ee20
class     0x103bd8988 0x103bd8f58

What's the difference between interface and @interface in java?

The interface keyword indicates that you are declaring a traditional interface class in Java.
The @interface keyword is used to declare a new annotation type.

See docs.oracle tutorial on annotations for a description of the syntax.
See the JLS if you really want to get into the details of what @interface means.

Running CMake on Windows

The default generator for Windows seems to be set to NMAKE. Try to use:

cmake -G "MinGW Makefiles"

Or use the GUI, and select MinGW Makefiles when prompted for a generator. Don't forget to cleanup the directory where you tried to run CMake, or delete the cache in the GUI. Otherwise, it will try again with NMAKE.

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

Jim's answer to this question may help; I copy it here. Quoting Guido van Rossum:

First of all, I chose len(x) over x.len() for HCI reasons (def __len__() came much later). There are two intertwined reasons actually, both HCI:

(a) For some operations, prefix notation just reads better than postfix — prefix (and infix!) operations have a long tradition in mathematics which likes notations where the visuals help the mathematician thinking about a problem. Compare the easy with which we rewrite a formula like x*(a+b) into xa + xb to the clumsiness of doing the same thing using a raw OO notation.

(b) When I read code that says len(x) I know that it is asking for the length of something. This tells me two things: the result is an integer, and the argument is some kind of container. To the contrary, when I read x.len(), I have to already know that x is some kind of container implementing an interface or inheriting from a class that has a standard len(). Witness the confusion we occasionally have when a class that is not implementing a mapping has a get() or keys() method, or something that isn’t a file has a write() method.

Saying the same thing in another way, I see ‘len‘ as a built-in operation. I’d hate to lose that. /…/

What is the OR operator in an IF statement

OR is used as "||"

 if(expr1 || expr2)
 {
    do something
 }

How to implement if-else statement in XSLT?

If I may offer some suggestions (two years later but hopefully helpful to future readers):

  • Factor out the common h2 element.
  • Factor out the common ooooooooooooo text.
  • Be aware of new XPath 2.0 if/then/else construct if using XSLT 2.0.

XSLT 1.0 Solution (also works with XSLT 2.0)

<h2>
  <xsl:choose>
    <xsl:when test="$CreatedDate > $IDAppendedDate">m</xsl:when>
    <xsl:otherwise>d</xsl:otherwise>
  </xsl:choose>
  ooooooooooooo
</h2>

XSLT 2.0 Solution

<h2>
   <xsl:value-of select="if ($CreatedDate > $IDAppendedDate) then 'm' else 'd'"/>
   ooooooooooooo
</h2>

Convert dataframe column to 1 or 0 for "true"/"false" values and assign to dataframe

Even when you asked finally for the opposite, to reform 0s and 1s into Trues and Falses, however, I post an answer about how to transform falses and trues into ones and zeros (1s and 0s), for a whole dataframe, in a single line.

Example given

df <- structure(list(p1_1 = c(TRUE, FALSE, FALSE, NA, TRUE, FALSE, 
                NA), p1_2 = c(FALSE, TRUE, FALSE, NA, FALSE, NA, 
                TRUE), p1_3 = c(TRUE, 
                TRUE, FALSE, NA, NA, FALSE, TRUE), p1_4 = c(FALSE, NA, 
                FALSE,  FALSE, TRUE, FALSE, NA), p1_5 = c(TRUE, NA, 
                FALSE, TRUE, FALSE, NA, TRUE), p1_6 = c(TRUE, NA, 
                FALSE, TRUE, FALSE, NA, TRUE), p1_7 = c(TRUE, NA, 
                FALSE, TRUE, NA, FALSE, TRUE), p1_8 = c(FALSE, 
                FALSE, NA, FALSE, TRUE, FALSE, NA), p1_9 = c(TRUE, 
                FALSE,  NA, FALSE, FALSE, NA, TRUE), p1_10 = c(TRUE, 
                FALSE, NA, FALSE, FALSE, NA, TRUE), p1_11 = c(FALSE, 
                FALSE, NA, FALSE, NA, FALSE, TRUE)), .Names = 
                c("p1_1", "p1_2", "p1_3", "p1_4", "p1_5", "p1_6", 
                "p1_7", "p1_8", "p1_9", "p1_10", "p1_11"), row.names = 
                 c(NA, -7L), class = "data.frame")

   p1_1  p1_2  p1_3  p1_4  p1_5  p1_6  p1_7  p1_8  p1_9 p1_10 p1_11
1  TRUE FALSE  TRUE FALSE  TRUE  TRUE  TRUE FALSE  TRUE  TRUE FALSE
2 FALSE  TRUE  TRUE    NA    NA    NA    NA FALSE FALSE FALSE FALSE
3 FALSE FALSE FALSE FALSE FALSE FALSE FALSE    NA    NA    NA    NA
4    NA    NA    NA FALSE  TRUE  TRUE  TRUE FALSE FALSE FALSE FALSE
5  TRUE FALSE    NA  TRUE FALSE FALSE    NA  TRUE FALSE FALSE    NA
6 FALSE    NA FALSE FALSE    NA    NA FALSE FALSE    NA    NA FALSE
7    NA  TRUE  TRUE    NA  TRUE  TRUE  TRUE    NA  TRUE  TRUE  TRUE

Then by running that: df * 1 all Falses and Trues are trasnformed into 1s and 0s. At least, this was happen in the R version that I have (R version 3.4.4 (2018-03-15) ).

> df*1
  p1_1 p1_2 p1_3 p1_4 p1_5 p1_6 p1_7 p1_8 p1_9 p1_10 p1_11
1    1    0    1    0    1    1    1    0    1     1     0
2    0    1    1   NA   NA   NA   NA    0    0     0     0
3    0    0    0    0    0    0    0   NA   NA    NA    NA
4   NA   NA   NA    0    1    1    1    0    0     0     0
5    1    0   NA    1    0    0   NA    1    0     0    NA
6    0   NA    0    0   NA   NA    0    0   NA    NA     0
7   NA    1    1   NA    1    1    1   NA    1     1     1

I do not know if it a total "safe" command, under all different conditions / dfs.

How to download fetch response in react as file

I needed to just download a file onClick but I needed to run some logic to either fetch or compute the actual url where the file existed. I also did not want to use any anti-react imperative patterns like setting a ref and manually clicking it when I had the resource url. The declarative pattern I used was

onClick = () => {
  // do something to compute or go fetch
  // the url we need from the server
  const url = goComputeOrFetchURL();

  // window.location forces the browser to prompt the user if they want to download it
  window.location = url
}

render() {
  return (
    <Button onClick={ this.onClick } />
  );
}

How do you unit test private methods?

CC -Dprivate=public

"CC" is the command line compiler on the system I use. -Dfoo=bar does the equivalent of #define foo bar. So, this compilation option effectively changes all private stuff to public.

Printing hexadecimal characters in C

Indeed, there is type conversion to int. Also you can force type to char by using %hhx specifier.

printf("%hhX", a);

In most cases you will want to set the minimum length as well to fill the second character with zeroes:

printf("%02hhX", a);

ISO/IEC 9899:201x says:

7 The length modifiers and their meanings are: hh Specifies that a following d, i, o, u, x, or X conversion specifier applies to a signed char or unsigned char argument (the argument will have been promoted according to the integer promotions, but its value shall be converted to signed char or unsigned char before printing); or that a following

Removing MySQL 5.7 Completely

First of all, do a backup of your needed databases with mysqldump

Note: If you want to restore later, just backup your relevant databases, and not the WHOLE, because the whole database might actually be the reason you need to purge and reinstall).

In total, do this:

sudo service mysql stop  #or mysqld
sudo killall -9 mysql
sudo killall -9 mysqld
sudo apt-get remove --purge mysql-server mysql-client mysql-common
sudo apt-get autoremove
sudo apt-get autoclean
sudo deluser -f mysql
sudo rm -rf /var/lib/mysql
sudo apt-get purge mysql-server-core-5.7
sudo apt-get purge mysql-client-core-5.7
sudo rm -rf /var/log/mysql
sudo rm -rf /etc/mysql

All above commands in single line (just copy and paste):

sudo service mysql stop && sudo killall -9 mysql && sudo killall -9 mysqld && sudo apt-get remove --purge mysql-server mysql-client mysql-common && sudo apt-get autoremove && sudo apt-get autoclean && sudo deluser mysql && sudo rm -rf /var/lib/mysql && sudo apt-get purge mysql-server-core-5.7 && sudo apt-get purge mysql-client-core-5.7 && sudo rm -rf /var/log/mysql && sudo rm -rf /etc/mysql

Spring can you autowire inside an abstract class?

In my case, inside a Spring4 Application, i had to use a classic Abstract Factory Pattern(for which i took the idea from - http://java-design-patterns.com/patterns/abstract-factory/) to create instances each and every time there was a operation to be done.So my code was to be designed like:

public abstract class EO {
    @Autowired
    protected SmsNotificationService smsNotificationService;
    @Autowired
    protected SendEmailService sendEmailService;
    ...
    protected abstract void executeOperation(GenericMessage gMessage);
}

public final class OperationsExecutor {
    public enum OperationsType {
        ENROLL, CAMPAIGN
    }

    private OperationsExecutor() {
    }

    public static Object delegateOperation(OperationsType type, Object obj) 
    {
        switch(type) {
            case ENROLL:
                if (obj == null) {
                    return new EnrollOperation();
                }
                return EnrollOperation.validateRequestParams(obj);
            case CAMPAIGN:
                if (obj == null) {
                    return new CampaignOperation();
                }
                return CampaignOperation.validateRequestParams(obj);
            default:
                throw new IllegalArgumentException("OperationsType not supported.");
        }
    }
}

@Configurable(dependencyCheck = true)
public class CampaignOperation extends EO {
    @Override
    public void executeOperation(GenericMessage genericMessage) {
        LOGGER.info("This is CAMPAIGN Operation: " + genericMessage);
    }
}

Initially to inject the dependencies in the abstract class I tried all stereotype annotations like @Component, @Service etc but even though Spring context file had ComponentScanning for the entire package, but somehow while creating instances of Subclasses like CampaignOperation, the Super Abstract class EO was having null for its properties as spring was unable to recognize and inject its dependencies.After much trial and error I used this **@Configurable(dependencyCheck = true)** annotation and finally Spring was able to inject the dependencies and I was able to use the properties in the subclass without cluttering them with too many properties.

<context:annotation-config />
<context:component-scan base-package="com.xyz" />

I also tried these other references to find a solution:

  1. http://www.captaindebug.com/2011/06/implementing-springs-factorybean.html#.WqF5pJPwaAN
  2. http://forum.spring.io/forum/spring-projects/container/46815-problem-with-autowired-in-abstract-class
  3. https://github.com/cavallefano/Abstract-Factory-Pattern-Spring-Annotation
  4. http://www.jcombat.com/spring/factory-implementation-using-servicelocatorfactorybean-in-spring
  5. https://www.madbit.org/blog/programming/1074/1074/#sthash.XEJXdIR5.dpbs
  6. Using abstract factory with Spring framework
  7. Spring Autowiring not working for Abstract classes
  8. Inject spring dependency in abstract super class
  9. Spring and Abstract class - injecting properties in abstract classes
    1. Spring autowire dependency defined in an abstract class

Please try using **@Configurable(dependencyCheck = true)** and update this post, I might try helping you if you face any problems.

Firefox 'Cross-Origin Request Blocked' despite headers

If you don't have a 'real' certificate (and thus using a self-signed one), in Firefox you can go to:

Options > Privacy & Security > (scroll to the bottom) View Certificates > Servers > Add Exception...

There, fill in the location, eg: https://www.myserver:myport

Replace a value in a data frame based on a conditional (`if`) statement

Short answer is:

junk$nm[junk$nm %in% "B"] <- "b"

Take a look at Index vectors in R Introduction (if you don't read it yet).


EDIT. As noticed in comments this solution works for character vectors so fail on your data.

For factor best way is to change level:

levels(junk$nm)[levels(junk$nm)=="B"] <- "b"

Could not load file or assembly ... An attempt was made to load a program with an incorrect format (System.BadImageFormatException)

This also can happen just by having multiple supported frameworks defined in the app.config file and, forcing the app to run in a different .NET framework other than the one mentioned first in the app.config file.

And also this fires when you have both of the mentioned frameworks available in your system.

As a workaround, bring up the target framework you are going to use for the debugging up in the app.config

ex: if you trying to run in .NET 4, config file should have something similar to this,

<supportedRuntime version="v4.0"/>
<supportedRuntime version="v2.0.50727"/>

PHP header(Location: ...): Force URL change in address bar

In your form element add data-ajax="false". I had the same problem using jquery mobile.

How to read a .properties file which contains keys that have a period character using Shell script

@fork2x

I have tried like this .Please review and update me whether it is right approach or not.

#/bin/sh
function pause(){
   read -p "$*"
}

file="./apptest.properties"


if [ -f "$file" ]
then
    echo "$file found."

dbUser=`sed '/^\#/d' $file | grep 'db.uat.user'  | tail -n 1 | cut -d "=" -f2- | sed 's/^[[:space:]]*//;s/[[:space:]]*$//'`
dbPass=`sed '/^\#/d' $file | grep 'db.uat.passwd'  | tail -n 1 | cut -d "=" -f2- | sed 's/^[[:space:]]*//;s/[[:space:]]*$//'`

echo database user = $dbUser
echo database pass = $dbPass

else
    echo "$file not found."
fi

View a specific Git commit

git show <revhash>

Documentation here. Or if that doesn't work, try Google Code's GIT Documentation

How to include JavaScript file or library in Chrome console?

Do you use some AJAX framework? Using jQuery it would be:

$.getScript('script.js');

If you're not using any framework then see the answer by Harmen.

(Maybe it is not worth to use jQuery just to do this one simple thing (or maybe it is) but if you already have it loaded then you might as well use it. I have seen websites that have jQuery loaded e.g. with Bootstrap but still use the DOM API directly in a way that is not always portable, instead of using the already loaded jQuery for that, and many people are not aware of the fact that even getElementById() doesn't work consistently on all browsers - see this answer for details.)

UPDATE:

It's been years since I wrote this answer and I think it's worth pointing out here that today you can use:

to dynamically load scripts. Those may be relevant to people reading this question.

See also: The Fluent 2014 talk by Guy Bedford: Practical Workflows for ES6 Modules.

Want custom title / image / description in facebook share link from a flash app

I think this site has the solution, i will test it now. It Seems like facebook has changed the parameters of share.php so, in order to customize share window text and images you have to put parameters in a "p" array.

http://www.daddydesign.com/wordpress/how-to-create-a-custom-facebook-share-button-for-your-iframe-tab/

Check it out.

Datatables on-the-fly resizing

You should try this one.

var table = $('#example').DataTable();
table.columns.adjust().draw();

Link: column adjust in datatable

SQL Query with Join, Count and Where

SELECT COUNT(*), table1.category_id, table2.category_name 
FROM table1 
INNER JOIN table2 ON table1.category_id=table2.category_id 
WHERE table1.colour <> 'red'
GROUP BY table1.category_id, table2.category_name 

Converting URL to String and back again

2020 | SWIFT 5.1:

From STRING to URL:

let url = URL(fileURLWithPath: "//Users/Me/Desktop/Doc.txt")

From URL to STRING:

let a = String(describing: url)       // "file:////Users/Me/Desktop/Doc.txt"
let b = "\(url)"                      // "file:////Users/Me/Desktop/Doc.txt"
let c = url.absoluteString            // "file:////Users/Me/Desktop/Doc.txt"
let d = url.path                      // "/Users/Me/Desktop/Doc.txt" 

BUT value of d will be invisible due to debug process, so...

THE BEST SOLUTION:

let e = "\(url.path)"                 // "/Users/Me/Desktop/Doc.txt"

Enable CORS in fetch api

Browser have cross domain security at client side which verify that server allowed to fetch data from your domain. If Access-Control-Allow-Origin not available in response header, browser disallow to use response in your JavaScript code and throw exception at network level. You need to configure cors at your server side.

You can fetch request using mode: 'cors'. In this situation browser will not throw execption for cross domain, but browser will not give response in your javascript function.

So in both condition you need to configure cors in your server or you need to use custom proxy server.

How can I compile a Java program in Eclipse without running it?

Try this in your console:

javac {$PathToYourProyect}/*

If you also need any external library, try:

javac -cp {$PathToYourLibrary}.jar {$PathToYourProyect}/*

C# string reference type?

"A picture is worth a thousand words".

I have a simple example here, it's similar to your case.

string s1 = "abc";
string s2 = s1;
s1 = "def";
Console.WriteLine(s2);
// Output: abc

This is what happened:

enter image description here

  • Line 1 and 2: s1 and s2 variables reference to the same "abc" string object.
  • Line 3: Because strings are immutable, so the "abc" string object do not modify itself (to "def"), but a new "def" string object is created instead, and then s1 references to it.
  • Line 4: s2 still references to "abc" string object, so that's the output.

Opening new window in HTML for target="_blank"

You can't influence neither type (tab/window) nor dimensions that way. You'll have to use JavaScript's window.open() for that.

Parse JSON String into a Particular Object Prototype in JavaScript

See an example below (this example uses the native JSON object). My changes are commented in CAPITALS:

function Foo(obj) // CONSTRUCTOR CAN BE OVERLOADED WITH AN OBJECT
{
    this.a = 3;
    this.b = 2;
    this.test = function() {return this.a*this.b;};

    // IF AN OBJECT WAS PASSED THEN INITIALISE PROPERTIES FROM THAT OBJECT
    for (var prop in obj) this[prop] = obj[prop];
}

var fooObj = new Foo();
alert(fooObj.test() ); //Prints 6

// INITIALISE A NEW FOO AND PASS THE PARSED JSON OBJECT TO IT
var fooJSON = new Foo(JSON.parse('{"a":4,"b":3}'));

alert(fooJSON.test() ); //Prints 12

jQuery - Follow the cursor with a DIV

You don't need jQuery for this. Here's a simple working example:

<!DOCTYPE html>
<html>
    <head>
        <title>box-shadow-experiment</title>
        <style type="text/css">
            #box-shadow-div{
                position: fixed;
                width: 1px;
                height: 1px;
                border-radius: 100%;
                background-color:black;
                box-shadow: 0 0 10px 10px black;
                top: 49%;
                left: 48.85%;
            }
        </style>
        <script type="text/javascript">
            window.onload = function(){
                var bsDiv = document.getElementById("box-shadow-div");
                var x, y;
    // On mousemove use event.clientX and event.clientY to set the location of the div to the location of the cursor:
                window.addEventListener('mousemove', function(event){
                    x = event.clientX;
                    y = event.clientY;                    
                    if ( typeof x !== 'undefined' ){
                        bsDiv.style.left = x + "px";
                        bsDiv.style.top = y + "px";
                    }
                }, false);
            }
        </script>
    </head>
    <body>
        <div id="box-shadow-div"></div>
    </body>
</html>

I chose position: fixed; so scrolling wouldn't be an issue.

Setting background color for a JFrame

You can use a container like so:

Container c = JFrame.getContentPane();
c.setBackground(Color.red); 

You must of course import java.awt.Color for the red color constant.

How to use operator '-replace' in PowerShell to replace strings of texts with special characters and replace successfully

'-replace' does a regex search and you have special characters in that last one (like +) So you might use the non-regex replace version like this:

$c = $c.replace('AccountKey=eKkij32jGEIYIEqAR5RjkKgf4OTiMO6SAyF68HsR/Zd/KXoKvSdjlUiiWyVV2+OUFOrVsd7jrzhldJPmfBBpQA==','DdOegAhDmLdsou6Ms6nPtP37bdw6EcXucuT47lf9kfClA6PjGTe3CfN+WVBJNWzqcQpWtZf10tgFhKrnN48lXA==')

Abstract Class vs Interface in C++

An abstract class would be used when some common implementation was required. An interface would be if you just want to specify a contract that parts of the program have to conform too. By implementing an interface you are guaranteeing that you will implement certain methods. By extending an abstract class you are inheriting some of it's implementation. Therefore an interface is just an abstract class with no methods implemented (all are pure virtual).

CodeIgniter - How to return Json response from controller

//do the edit in your javascript

$('.signinform').submit(function() { 
   $(this).ajaxSubmit({ 
       type : "POST",
       //set the data type
       dataType:'json',
       url: 'index.php/user/signin', // target element(s) to be updated with server response 
       cache : false,
       //check this in Firefox browser
       success : function(response){ console.log(response); alert(response)},
       error: onFailRegistered
   });        
   return false; 
}); 


//controller function

public function signin() {
    $arr = array('a' => 1, 'b' => 2, 'c' => 3, 'd' => 4, 'e' => 5);    

   //add the header here
    header('Content-Type: application/json');
    echo json_encode( $arr );
}

Why is the Android emulator so slow? How can we speed up the Android emulator?

Try using the Intel X86 Atom Storage Image for a relatively faster boot up than using ARM based images when emulating the device.

Another thing to be taken into the notice is that according to your system configuration, running an Android emulator with 1.21 GB RAM can be a sluggish experience, because the emulator requires up to some certain percentage of RAM which is used for emulating the device, not forgetting about the RAM used by the ADT.

Try a system image of 2.1 - 2.3.3 for at least a runnable experience. Plus not forgetting about Save to Snapshot for quicker loading. Though the first load may take time. But saving to a snapshot definitely saves up some time.

Adding a regression line on a ggplot

The simple solution using geom_abline:

geom_abline(slope = coef(data.lm)[[2]], intercept = coef(data.lm)[[1]])

Where data.lm is an lm object, and coef(data.lm) looks something like this:

> coef(data.lm)
(Intercept)    DepDelay 
  -2.006045    1.025109 

The numeric indexing assumes that (Intercept) is listed first, which is the case if the model includes an intercept. If you have some other linear model object, just plug in the slope and intercept values similarly.

Replace all non Alpha Numeric characters, New Lines, and multiple White Space with one Space

Well I think you just need to add a quantifier to each pattern. Also the carriage-return thing is a little funny:

text.replace(/[^a-z0-9]+|\s+/gmi, " ");

edit The \s thing matches \r and \n too.

Disable browser's back button

This seems to have worked for us.

history.pushState(null, null, $(location).attr('href'));
window.addEventListener('popstate', function () {
    history.pushState(null, null, $(location).attr('href'));
});

How to check if an element is visible with WebDriver

Verifying ele is visible.

public static boolean isElementVisible(final By by)
    throws InterruptedException {
        boolean value = false;

        if (driver.findElements(by).size() > 0) {
            value = true;
        }
        return value;
    }

Sending Multipart File as POST parameters with RestTemplate requests

If you have to send a multipart file that is composed, among other things, by an Object that needs to be converted with a specific HttpMessageConverter and you get the "no suitable HttpMessageConverter" error no matter what you try, you may want to try with this:

RestTemplate restTemplate = new RestTemplate();
FormHttpMessageConverter converter = new FormHttpMessageConverter();

converter.addPartConverter(new TheRequiredHttpMessageConverter());
//for example, in my case it was "new MappingJackson2HttpMessageConverter()"

restTemplate.getMessageConverters().add(converter);

This solved the problem for me with a custom Object that, together with a file (instanceof FileSystemResource, in my case), was part of the multipart file I needed to send. I tried with TrueGuidance's solution (and many others found around the web) to no avail, then I looked at FormHttpMessageConverter's source code and tried this.

Print number of keys in Redis

WARNING: Do not run this on a production machine.

On a Linux box:

redis-cli KEYS "*" | wc -l

Note: As mentioned in comments below, this is an O(N) operation, so on a large DB with many keys you should not use this. For smaller deployments, it should be fine.

How do I use FileSystemObject in VBA?

In excel 2013 the object creation string is:

Dim fso
Set fso = CreateObject("Scripting.FileSystemObject")

instead of the code in the answer above:

Dim fs,fname
Set fs=Server.CreateObject("Scripting.FileSystemObject")

Change event on select with knockout binding, how can I know if it is a real change?

If you use an observable instead of a primitive value, the select will not raise change events on initial binding. You can continue to bind to the change event, rather than subscribing directly to the observable.

Render Content Dynamically from an array map function in React Native

lapsList() {

    return this.state.laps.map((data) => {
      return (
        <View><Text>{data.time}</Text></View>
      )
    })
}

You forgot to return the map. this code will resolve the issue.

How do you run your own code alongside Tkinter's event loop?

Another option is to let tkinter execute on a separate thread. One way of doing it is like this:

import Tkinter
import threading

class MyTkApp(threading.Thread):
    def __init__(self):
        self.root=Tkinter.Tk()
        self.s = Tkinter.StringVar()
        self.s.set('Foo')
        l = Tkinter.Label(self.root,textvariable=self.s)
        l.pack()
        threading.Thread.__init__(self)

    def run(self):
        self.root.mainloop()


app = MyTkApp()
app.start()

# Now the app should be running and the value shown on the label
# can be changed by changing the member variable s.
# Like this:
# app.s.set('Bar')

Be careful though, multithreaded programming is hard and it is really easy to shoot your self in the foot. For example you have to be careful when you change member variables of the sample class above so you don't interrupt with the event loop of Tkinter.

RegEx for Javascript to allow only alphanumeric

Input these code to your SCRATCHPAD and see the action.

var str=String("Blah-Blah1_2,oo0.01&zz%kick").replace(/[^\w-]/ig, '');

Copying HTML code in Google Chrome's inspect element

Do the following:

  1. Select the top most element, you want to copy. (To copy all, select <html>)
  2. Right click.
  3. Select Edit as HTML
  4. New sub-window opens up with the HTML text.
  5. This is your chance. Press CTRL+A/CTRL+C and copy the entire text field to a different window.

This is a hacky way, but it's the easiest way to do this.

Recommended way of making React component/div draggable

I would like to add a 3rd Scenario

The moving position is not saved in any way. Think of it as a mouse movement - your cursor is not a React-component, right?

All you do, is to add a prop like "draggable" to your component and a stream of the dragging events that will manipulate the dom.

setXandY: function(event) {
    // DOM Manipulation of x and y on your node
},

componentDidMount: function() {
    if(this.props.draggable) {
        var node = this.getDOMNode();
        dragStream(node).onValue(this.setXandY);  //baconjs stream
    };
},

In this case, a DOM manipulation is an elegant thing (I never thought I'd say this)

Of Countries and their Cities

This service returns Countries (name,code) and cities for any country as REST, SErvice. You can also download database and sample REST service

http://tecorange.com/content/world-countries-and-cities-restjson-service-12-months-subscription

SQL Server datetime LIKE select?

There is a very flaky coverage of the LIKE operator for dates in SQL Server. It only works using American date format. As an example you could try:

... WHERE register_date LIKE 'oct 10 2009%'

I've tested this in SQL Server 2005 and it works, but you'll really need to try different combinations. Odd things I have noticed are:

  • You only seem to get all or nothing for different sub fields within the date, for instance, if you search for 'apr 2%' you only get anything in the 20th's - it omits 2nd's.

  • Using a single underscore '_' to represent a single (wildcard) character does not wholly work, for instance, WHERE mydate LIKE 'oct _ 2010%' will not return all dates before the 10th - it returns nothing at all, in fact!

  • The format is rigid American: 'mmm dd yyyy hh:mm'

I have found it difficult to nail down a process for LIKEing seconds, so if anyone wants to take this a bit further, be my guest!

Hope this helps.

How to create a DataFrame from a text file in Spark

You can read a file to have an RDD and then assign schema to it. Two common ways to creating schema are either using a case class or a Schema object [my preferred one]. Follows the quick snippets of code that you may use.

Case Class approach

case class Test(id:String,name:String)
val myFile = sc.textFile("file.txt")
val df= myFile.map( x => x.split(";") ).map( x=> Test(x(0),x(1)) ).toDF()

Schema Approach

import org.apache.spark.sql.types._
val schemaString = "id name"
val fields = schemaString.split(" ").map(fieldName => StructField(fieldName, StringType, nullable=true))
val schema = StructType(fields)

val dfWithSchema = sparkSess.read.option("header","false").schema(schema).csv("file.txt")
dfWithSchema.show()

The second one is my preferred approach since case class has a limitation of max 22 fields and this will be a problem if your file has more than 22 fields!

Calculate distance between two latitude-longitude points? (Haversine formula)

Here's another converted to Ruby code:

include Math
#Note: from/to = [lat, long]

def get_distance_in_km(from, to)
  radians = lambda { |deg| deg * Math.PI / 180 }
  radius = 6371 # Radius of the earth in kilometer
  dLat = radians[to[0]-from[0]]
  dLon = radians[to[1]-from[1]]

  cosines_product = Math.sin(dLat/2) * Math.sin(dLat/2) + Math.cos(radians[from[0]]) * Math.cos(radians[to[1]]) * Math.sin(dLon/2) * Math.sin(dLon/2)

  c = 2 * Math.atan2(Math.sqrt(cosines_product), Math.sqrt(1-cosines_product)) 
  return radius * c # Distance in kilometer
end

macro for Hide rows in excel 2010

You almost got it. You are hiding the rows within the active sheet. which is okay. But a better way would be add where it is.

Rows("52:55").EntireRow.Hidden = False

becomes

activesheet.Rows("52:55").EntireRow.Hidden = False

i've had weird things happen without it. As for making it automatic. You need to use the worksheet_change event within the sheet's macro in the VBA editor (not modules, double click the sheet1 to the far left of the editor.) Within that sheet, use the drop down menu just above the editor itself (there should be 2 listboxes). The listbox to the left will have the events you are looking for. After that just throw in the macro. It should look like the below code,

Private Sub Worksheet_Change(ByVal Target As Range)
test1
end Sub

That's it. Anytime you change something, it will run the macro test1.

C# switch statement limitations - why?

C# 8 allows you to solve this problem elegantly and compactly using an switch expression:

public string GetTypeName(object obj)
{
    return obj switch
    {
        int i => "Int32",
        string s => "String",
        { } => "Unknown",
        _ => throw new ArgumentNullException(nameof(obj))
    };
}

As a result, you get:

Console.WriteLine(GetTypeName(obj: 1));           // Int32
Console.WriteLine(GetTypeName(obj: "string"));    // String
Console.WriteLine(GetTypeName(obj: 1.2));         // Unknown
Console.WriteLine(GetTypeName(obj: null));        // System.ArgumentNullException

You can read more about the new feature here.

getting the index of a row in a pandas apply function

To access the index in this case you access the name attribute:

In [182]:

df = pd.DataFrame([[1,2,3],[4,5,6]], columns=['a','b','c'])
def rowFunc(row):
    return row['a'] + row['b'] * row['c']

def rowIndex(row):
    return row.name
df['d'] = df.apply(rowFunc, axis=1)
df['rowIndex'] = df.apply(rowIndex, axis=1)
df
Out[182]:
   a  b  c   d  rowIndex
0  1  2  3   7         0
1  4  5  6  34         1

Note that if this is really what you are trying to do that the following works and is much faster:

In [198]:

df['d'] = df['a'] + df['b'] * df['c']
df
Out[198]:
   a  b  c   d
0  1  2  3   7
1  4  5  6  34

In [199]:

%timeit df['a'] + df['b'] * df['c']
%timeit df.apply(rowIndex, axis=1)
10000 loops, best of 3: 163 µs per loop
1000 loops, best of 3: 286 µs per loop

EDIT

Looking at this question 3+ years later, you could just do:

In[15]:
df['d'],df['rowIndex'] = df['a'] + df['b'] * df['c'], df.index
df

Out[15]: 
   a  b  c   d  rowIndex
0  1  2  3   7         0
1  4  5  6  34         1

but assuming it isn't as trivial as this, whatever your rowFunc is really doing, you should look to use the vectorised functions, and then use them against the df index:

In[16]:
df['newCol'] = df['a'] + df['b'] + df['c'] + df.index
df

Out[16]: 
   a  b  c   d  rowIndex  newCol
0  1  2  3   7         0       6
1  4  5  6  34         1      16

Using Linq to group a list of objects into a new grouped list of list of objects

For type

public class KeyValue
{
    public string KeyCol { get; set; }
    public string ValueCol { get; set; }
}

collection

var wordList = new Model.DTO.KeyValue[] {
    new Model.DTO.KeyValue {KeyCol="key1", ValueCol="value1" },
    new Model.DTO.KeyValue {KeyCol="key2", ValueCol="value1" },
    new Model.DTO.KeyValue {KeyCol="key3", ValueCol="value2" },
    new Model.DTO.KeyValue {KeyCol="key4", ValueCol="value2" },
    new Model.DTO.KeyValue {KeyCol="key5", ValueCol="value3" },
    new Model.DTO.KeyValue {KeyCol="key6", ValueCol="value4" }
};

our linq query look like below

var query =from m in wordList group m.KeyCol by m.ValueCol into g
select new { Name = g.Key, KeyCols = g.ToList() };

or for array instead of list like below

var query =from m in wordList group m.KeyCol by m.ValueCol into g
select new { Name = g.Key, KeyCols = g.ToList().ToArray<string>() };

c# datatable insert column at position 0

Just to improve Wael's answer and put it on a single line:

dt.Columns.Add("Better", typeof(Boolean)).SetOrdinal(0);

UPDATE: Note that this works when you don't need to do anything else with the DataColumn. Add() returns the column in question, SetOrdinal() returns nothing.

password for postgres

Set the default password in the .pgpass file. If the server does not save the password, it is because it is not set in the .pgpass file, or the permissions are open and the file is therefore ignored.

Read more about the password file here.

Also, be sure to check the permissions: on *nix systems the permissions on .pgpass must disallow any access to world or group; achieve this by the command chmod 0600 ~/.pgpass. If the permissions are less strict than this, the file will be ignored.

Have you tried logging-in using PGAdmin? You can save the password there, and modify the pgpass file.

Extract elements of list at odd positions

For the odd positions, you probably want:

>>>> list_ = list(range(10))
>>>> print list_[1::2]
[1, 3, 5, 7, 9]
>>>>

jquery disable form submit on enter

$(document).on('keyup keypress', 'form input[type="text"]', function(e) {
  if(e.which == 13) {
    e.preventDefault();
    return false;
  }
});

This solution works on all forms on website (also on forms inserted with ajax), preventing only Enters in input texts. Place it in a document ready function, and forget this problem for a life.

Centering in CSS Grid

Try using flex:

Plunker demo : https://plnkr.co/edit/nk02ojKuXD2tAqZiWvf9

/* Styles go here */

html,
body {
  margin: 0;
  padding: 0;
}

.container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 100vh;
  grid-gap: 0px 0px;
}

.left_bg {
  background-color: #3498db;
  grid-column: 1 / 1;
  grid-row: 1 / 1;
  z-index: 0;
  display: flex;
  justify-content: center;
  align-items: center;

}

.right_bg {
  background-color: #ecf0f1;
  grid-column: 2 / 2;
  grid_row: 1 / 1;
  z-index: 0;
  display: flex;
  justify-content: center;
  align-items: center;
}

.text {
  font-family: Raleway;
  font-size: large;
  text-align: center;
}

HTML

    <div class="container">
  <!--everything on the page-->

  <div class="left_bg">
    <!--left background color of the page-->
    <div class="text">
      <!--left side text content-->
      <p>Review my stuff</p>
    </div>
  </div>

  <div class="right_bg">
    <!--right background color of the page-->
    <div class="text">
      <!--right side text content-->
      <p>Hire me!</p>
    </div>
  </div>
</div>

SQL statement to get column type

In TSQL/MSSQL it looks like:

SELECT t.name, c.name 
FROM sys.tables t 
JOIN sys.columns c ON t.object_id = c.object_id
JOIN sys.types y ON y.user_type_id = c.user_type_id
WHERE t.name = ''

How to install MinGW-w64 and MSYS2?

Unfortunately, the MinGW-w64 installer you used sometimes has this issue. I myself am not sure about why this happens (I think it has something to do with Sourceforge URL redirection or whatever that the installer currently can't handle properly enough).

Anyways, if you're already planning on using MSYS2, there's no need for that installer.

  1. Download MSYS2 from this page (choose 32 or 64-bit according to what version of Windows you are going to use it on, not what kind of executables you want to build, both versions can build both 32 and 64-bit binaries).

  2. After the install completes, click on the newly created "MSYS2 Shell" option under either MSYS2 64-bit or MSYS2 32-bit in the Start menu. Update MSYS2 according to the wiki (although I just do a pacman -Syu, ignore all errors and close the window and open a new one, this is not recommended and you should do what the wiki page says).

  3. Install a toolchain

    a) for 32-bit:

    pacman -S mingw-w64-i686-gcc
    

    b) for 64-bit:

    pacman -S mingw-w64-x86_64-gcc
    
  4. install any libraries/tools you may need. You can search the repositories by doing

    pacman -Ss name_of_something_i_want_to_install
    

    e.g.

    pacman -Ss gsl
    

    and install using

    pacman -S package_name_of_something_i_want_to_install
    

    e.g.

    pacman -S mingw-w64-x86_64-gsl
    

    and from then on the GSL library is automatically found by your MinGW-w64 64-bit compiler!

  5. Open a MinGW-w64 shell:

    a) To build 32-bit things, open the "MinGW-w64 32-bit Shell"

    b) To build 64-bit things, open the "MinGW-w64 64-bit Shell"

  6. Verify that the compiler is working by doing

    gcc -v
    

If you want to use the toolchains (with installed libraries) outside of the MSYS2 environment, all you need to do is add <MSYS2 root>/mingw32/bin or <MSYS2 root>/mingw64/bin to your PATH.

How do I import other TypeScript files?

If you're using AMD modules, the other answers won't work in TypeScript 1.0 (the newest at the time of writing.)

You have different approaches available to you, depending upon how many things you wish to export from each .ts file.

Multiple exports

Foo.ts

export class Foo {}
export interface IFoo {}

Bar.ts

import fooModule = require("Foo");

var foo1 = new fooModule.Foo();
var foo2: fooModule.IFoo = {};

Single export

Foo.ts

class Foo
{}

export = Foo;

Bar.ts

import Foo = require("Foo");

var foo = new Foo();

PYTHONPATH on Linux

  1. PYTHONPATH is an environment variable
  2. Yes (see https://unix.stackexchange.com/questions/24802/on-which-unix-distributions-is-python-installed-as-part-of-the-default-install)
  3. /usr/lib/python2.7 on Ubuntu
  4. you shouldn't install packages manually. Instead, use pip. When a package isn't in pip, it usually has a setuptools setup script which will install the package into the proper location (see point 3).
  5. if you use pip or setuptools, then you don't need to set PYTHONPATH explicitly

If you look at the instructions for pyopengl, you'll see that they are consistent with points 4 and 5.

How to round to 2 decimals with Python?

Not sure why, but '{:0.2f}'.format(0.5357706) gives me '0.54'. The only solution that works for me (python 3.6) is the following:

def ceil_floor(x):
    import math
    return math.ceil(x) if x < 0 else math.floor(x)

def round_n_digits(x, n):
    import math
    return ceil_floor(x * math.pow(10, n)) / math.pow(10, n)

round_n_digits(-0.5357706, 2) -> -0.53 
round_n_digits(0.5357706, 2) -> 0.53

How do you get the footer to stay at the bottom of a Web page?

Here is a solution with jQuery that works like a charm. It checks if the height of the window is greater than the height of the body. If it is, then it changes the margin-top of the footer to compensate. Tested in Firefox, Chrome, Safari and Opera.

$( function () {

    var height_diff = $( window ).height() - $( 'body' ).height();
    if ( height_diff > 0 ) {
        $( '#footer' ).css( 'margin-top', height_diff );
    }

});

If your footer already has a margin-top (of 50 pixels, for example) you will need to change the last part for:

css( 'margin-top', height_diff + 50 )

Is there an opposite to display:none?

In the case of a printer friendly stylesheet, I use the following:

/* screen style */
.print_only { display: none; }

/* print stylesheet */
div.print_only { display: block; }
span.print_only { display: inline; }
.no_print { display: none; }

I used this when I needed to print a form containing values and the input fields were difficult to print. So I added the values wrapped in a span.print_only tag (div.print_only was used elsewhere) and then applied the .no_print class to the input fields. So on-screen you would see the input fields and when printed, only the values. If you wanted to get fancy you could use JS to update the values in the span tags when the fields were updated but that wasn't necessary in my case. Perhaps not the the most elegant solution but it worked for me!

Difference between $(document.body) and $('body')

I have found a pretty big difference in timing when testing in my browser.

I used the following script:

WARNING: running this will freeze your browser a bit, might even crash it.

_x000D_
_x000D_
var n = 10000000, i;_x000D_
i = n;_x000D_
console.time('selector');_x000D_
while (i --> 0){_x000D_
    $("body");_x000D_
}_x000D_
_x000D_
console.timeEnd('selector');_x000D_
_x000D_
i = n;_x000D_
console.time('element');_x000D_
while (i --> 0){_x000D_
    $(document.body);_x000D_
}_x000D_
_x000D_
console.timeEnd('element');
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
_x000D_
_x000D_
_x000D_

I did 10 million interactions, and those were the results (Chrome 65):

selector: 19591.97509765625ms
element: 4947.8759765625ms

Passing the element directly is around 4 times faster than passing the selector.

What is the use of a private static variable in Java?

For some people this makes more sense if they see it in a couple different languages so I wrote an example in Java, and PHP on my page where I explain some of these modifiers. You might be thinking about this incorrectly.

You should look at my examples if it doesn't make sense below. Go here http://www.siteconsortium.com/h/D0000D.php

The bottom line though is that it is pretty much exactly what it says it is. It's a static member variable that is private. For example if you wanted to create a Singleton object why would you want to make the SingletonExample.instance variable public. If you did a person who was using the class could easily overwrite the value.

That's all it is.


    public class SingletonExample {
      private static SingletonExample instance = null;
      private static int value = 0;
      private SingletonExample() {
        ++this.value;
      }
      public static SingletonExample getInstance() {
        if(instance!=null)
        return instance;
        synchronized(SingletonExample.class) {
        instance = new SingletonExample();
        return instance;
        }
      }
      public void printValue() {
        System.out.print( this.value );
      }

      public static void main(String [] args) {
        SingletonExample instance = getInstance();
        instance.printValue();
        instance = getInstance();
        instance.printValue();
         }
    }

Using .text() to retrieve only text not nested in child tags

It'll need to be something tailored to the needs, which are dependent on the structure you're presented with. For the example you've provided, this works:

$(document).ready(function(){
     var $tmp = $('#listItem').children().remove();
     $('#listItem').text('').append($tmp);
});

Demo: http://jquery.nodnod.net/cases/2385/run

But it's fairly dependent on the markup being similar to what you posted.

How to $watch multiple variable change in angular

There is many way to watch multiple values :

//angular 1.1.4
$scope.$watchCollection(['foo', 'bar'], function(newValues, oldValues){
    // do what you want here
});

or more recent version

//angular 1.3
$scope.$watchGroup(['foo', 'bar'], function(newValues, oldValues, scope) {
  //do what you want here
});

Read official doc for more informations : https://docs.angularjs.org/api/ng/type/$rootScope.Scope

Using C# regular expressions to remove HTML tags

try regular expression method at this URL: http://www.dotnetperls.com/remove-html-tags

/// <summary>
/// Remove HTML from string with Regex.
/// </summary>
public static string StripTagsRegex(string source)
{
return Regex.Replace(source, "<.*?>", string.Empty);
}

/// <summary>
/// Compiled regular expression for performance.
/// </summary>
static Regex _htmlRegex = new Regex("<.*?>", RegexOptions.Compiled);

/// <summary>
/// Remove HTML from string with compiled Regex.
/// </summary>
public static string StripTagsRegexCompiled(string source)
{
return _htmlRegex.Replace(source, string.Empty);
}

"X-UA-Compatible" content="IE=9; IE=8; IE=7; IE=EDGE"

In certain cases, it might be necessary to restrict the display of a webpage to a document mode supported by an earlier version of Internet Explorer. You can do this by serving the page with an x-ua-compatible header. For more info, see Specifying legacy document modes.
- https://msdn.microsoft.com/library/cc288325

Thus this tag is used to future proof the webpage, such that the older / compatible engine is used to render it the same way as intended by the creator.

Make sure that you have checked it to work properly with the IE version you specify.

Flask Python Buttons

Give your two buttons the same name and different values:

<input type="submit" name="submit_button" value="Do Something">
<input type="submit" name="submit_button" value="Do Something Else">

Then in your Flask view function you can tell which button was used to submit the form:

def contact():
    if request.method == 'POST':
        if request.form['submit_button'] == 'Do Something':
            pass # do something
        elif request.form['submit_button'] == 'Do Something Else':
            pass # do something else
        else:
            pass # unknown
    elif request.method == 'GET':
        return render_template('contact.html', form=form)

How to Access Hive via Python?

Simplest method | Using sqlalchemy

Requirements:

  • pip install pyhive

Code:

import pandas as pd
from sqlalchemy import create_engine

SECRET = {'username':'lol', 'password': 'lol'}
user_name = SECRET.get('username')
passwd = SECRET.get('password')

host_server = 'x.x.x.x'
port = '10000'
database = 'default'
conn = f'hive://{user_name}:{passwd}@{host_server}:{port}/{database}'
engine = create_engine(conn, connect_args={'auth': 'LDAP'})

query = "select * from tablename limit 100"
data = pd.read_sql(query, con=engine)
print(data)

Is it ok to use `any?` to check if an array is not empty?

The difference between an array evaluating its values to true or if its empty.

The method empty? comes from the Array class
http://ruby-doc.org/core-2.0.0/Array.html#method-i-empty-3F

It's used to check if the array contains something or not. This includes things that evaluate to false, such as nil and false.

>> a = []
=> []
>> a.empty?
=> true
>> a = [nil, false]
=> [nil, false]
>> a.empty?
=> false
>> a = [nil]
=> [nil]
>> a.empty?
=> false

The method any? comes from the Enumerable module.
http://ruby-doc.org/core-2.0.0/Enumerable.html#method-i-any-3F

It's used to evaluate if "any" value in the array evaluates to true. Similar methods to this are none?, all? and one?, where they all just check to see how many times true could be evaluated. which has nothing to do with the count of values found in a array.

case 1

>> a = []
=> []
>> a.any?
=> false
>> a.one?
=> false
>> a.all?
=> true
>> a.none?
=> true

case 2

>> a = [nil, true]
=> [nil, true]
>> a.any?
=> true
>> a.one?
=> true
>> a.all?
=> false
>> a.none?
=> false

case 3

>> a = [true, true]
=> [true, true]
>> a.any?
=> true
>> a.one?
=> false
>> a.all?
=> true
>> a.none?
=> false

How to create a file with a given size in Linux?

Use fallocate if you don't want to wait for disk.

Example:

fallocate -l 100G BigFile

Usage:

Usage:
 fallocate [options] <filename>

Preallocate space to, or deallocate space from a file.

Options:
 -c, --collapse-range remove a range from the file
 -d, --dig-holes      detect zeroes and replace with holes
 -i, --insert-range   insert a hole at range, shifting existing data
 -l, --length <num>   length for range operations, in bytes
 -n, --keep-size      maintain the apparent size of the file
 -o, --offset <num>   offset for range operations, in bytes
 -p, --punch-hole     replace a range with a hole (implies -n)
 -z, --zero-range     zero and ensure allocation of a range
 -x, --posix          use posix_fallocate(3) instead of fallocate(2)
 -v, --verbose        verbose mode

 -h, --help           display this help
 -V, --version        display version

Is there a label/goto in Python?

Python offers you the ability to do some of the things you could do with a goto using first class functions. For example:

void somefunc(int a)
{
    if (a == 1)
        goto label1;
    if (a == 2)
        goto label2;

    label1:
        ...
    label2:
        ...
}

Could be done in python like this:

def func1():
    ...

def func2():
    ...

funcmap = {1 : func1, 2 : func2}

def somefunc(a):
    funcmap[a]()  #Ugly!  But it works.

Granted, that isn't the best way to substitute for goto. But without knowing exactly what you're trying to do with the goto, it's hard to give specific advice.

@ascobol:

Your best bet is to either enclose it in a function or use an exception. For the function:

def loopfunc():
    while 1:
        while 1:
            if condition:
                return

For the exception:

try:
    while 1:
        while 1:
            raise BreakoutException #Not a real exception, invent your own
except BreakoutException:
    pass

Using exceptions to do stuff like this may feel a bit awkward if you come from another programming language. But I would argue that if you dislike using exceptions, Python isn't the language for you. :-)

Why can't Python parse this JSON data?

Here you go with modified data.json file:

{
    "maps": [
        {
            "id": "blabla",
            "iscategorical": "0"
        },
        {
            "id": "blabla",
            "iscategorical": "0"
        }
    ],
    "masks": [{
        "id": "valore"
    }],
    "om_points": "value",
    "parameters": [{
        "id": "valore"
    }]
}

You can call or print data on console by using below lines:

import json
from pprint import pprint
with open('data.json') as data_file:
    data_item = json.load(data_file)
pprint(data_item)

Expected output for print(data_item['parameters'][0]['id']):

{'maps': [{'id': 'blabla', 'iscategorical': '0'},
          {'id': 'blabla', 'iscategorical': '0'}],
 'masks': [{'id': 'valore'}],
 'om_points': 'value',
 'parameters': [{'id': 'valore'}]}

Expected output for print(data_item['parameters'][0]['id']):

valore

What is ROWS UNBOUNDED PRECEDING used for in Teradata?

It's the "frame" or "range" clause of window functions, which are part of the SQL standard and implemented in many databases, including Teradata.

A simple example would be to calculate the average amount in a frame of three days. I'm using PostgreSQL syntax for the example, but it will be the same for Teradata:

WITH data (t, a) AS (
  VALUES(1, 1),
        (2, 5),
        (3, 3),
        (4, 5),
        (5, 4),
        (6, 11)
)
SELECT t, a, avg(a) OVER (ORDER BY t ROWS BETWEEN 1 PRECEDING AND 1 FOLLOWING)
FROM data
ORDER BY t

... which yields:

t  a  avg
----------
1  1  3.00
2  5  3.00
3  3  4.33
4  5  4.00
5  4  6.67
6 11  7.50

As you can see, each average is calculated "over" an ordered frame consisting of the range between the previous row (1 preceding) and the subsequent row (1 following).

When you write ROWS UNBOUNDED PRECEDING, then the frame's lower bound is simply infinite. This is useful when calculating sums (i.e. "running totals"), for instance:

WITH data (t, a) AS (
  VALUES(1, 1),
        (2, 5),
        (3, 3),
        (4, 5),
        (5, 4),
        (6, 11)
)
SELECT t, a, sum(a) OVER (ORDER BY t ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW)
FROM data
ORDER BY t

yielding...

t  a  sum
---------
1  1    1
2  5    6
3  3    9
4  5   14
5  4   18
6 11   29

Here's another very good explanations of SQL window functions.

JavaScript, get date of the next day

Copy-pasted from here: Incrementing a date in JavaScript

Three options for you:

Using just JavaScript's Date object (no libraries):

var today = new Date();
var tomorrow = new Date(today.getTime() + (24 * 60 * 60 * 1000));

Or if you don't mind changing the date in place (rather than creating a new date):

var dt = new Date();
dt.setTime(dt.getTime() + (24 * 60 * 60 * 1000));

Edit: See also Jigar's answer and David's comment below: var tomorrow = new Date(); tomorrow.setDate(tomorrow.getDate() + 1);

Using MomentJS:

var today = moment();
var tomorrow = moment(today).add(1, 'days');

(Beware that add modifies the instance you call it on, rather than returning a new instance, so today.add(1, 'days') would modify today. That's why we start with a cloning op on var tomorrow = ....)

Using DateJS, but it hasn't been updated in a long time:

var today = new Date(); // Or Date.today()
var tomorrow = today.add(1).day();

How to list containers in Docker

To display only running containers

docker ps

To show all containers (includes all states)

docker ps -a

To show the latest created container (includes all states)

docker ps -l

To show n last created containers (includes all states)

docker ps -n=-1

To display total file sizes

docker ps -s

In the new version of Docker, commands are updated, and some management commands are added:

docker container ls

List all the running containers.

docker container ls -a

Changing SqlConnection timeout

I found an excellent blogpost on this subject: https://improve.dk/controlling-sqlconnection-timeouts/

Basically, you either set Connect Timeout in the connection string, or you set ConnectionTimeout on the command object.

Be aware that the timeout time is in seconds.

How can I pull from remote Git repository and override the changes in my local repository?

As an addendum, if you want to reapply your changes on top of the remote, you can also try:

git pull --rebase origin master

If you then want to undo some of your changes (but perhaps not all of them) you can use:

git reset SHA_HASH

Then do some adjustment and recommit.

Include of non-modular header inside framework module

Make sure the header files are publicly available as part of the framework's public headers.

Goto Framework -> Target -> Build Phases and drag to move the relevant header files from Project to Public. Hope that helps!

Screenshot

Get exit code for command in bash/ksh

The normal idea would be to run the command and then use $? to get the exit code. However, some times you have multiple cases in which you need to get the exit code. For example, you might need to hide it's output but still return the exit code, or print both the exit code and the output.

ec() { [[ "$1" == "-h" ]] && { shift && eval $* > /dev/null 2>&1; ec=$?; echo $ec; } || eval $*; ec=$?; }

This will give you the option to suppress the output of the command you want the exit code for. When the output is suppressed for the command, the exit code will directly be returned by the function.

I personally like to put this function in my .bashrc file

Below I demonstrate a few ways in which you can use this:


# In this example, the output for the command will be
# normally displayed, and the exit code will be stored
# in the variable $ec.

$ ec echo test
test
$ echo $ec
0

# In this example, the exit code is output
# and the output of the command passed
# to the `ec` function is suppressed.

$ echo "Exit Code: $(ec -h echo test)"
Exit Code: 0

# In this example, the output of the command
# passed to the `ec` function is suppressed
# and the exit code is stored in `$ec`

$ ec -h echo test
$ echo $ec
0

Solution to your code using this function

#!/bin/bash
if [[ "$(ec -h 'ls -l | grep p')" != "0" ]]; then
    echo "Error when executing command: 'grep p' [$ec]"
    exit $ec;
fi

You should also note that the exit code you will be seeing will be for the grep command that's being run, as it is the last command being executed. Not the ls.

How to disable button in React.js

Using refs is not best practice because it reads the DOM directly, it's better to use React's state instead. Also, your button doesn't change because the component is not re-rendered and stays in its initial state.

You can use setState together with an onChange event listener to render the component again every time the input field changes:

// Input field listens to change, updates React's state and re-renders the component.
<input onChange={e => this.setState({ value: e.target.value })} value={this.state.value} />

// Button is disabled when input state is empty.
<button disabled={!this.state.value} />

Here's a working example:

_x000D_
_x000D_
class AddItem extends React.Component {_x000D_
  constructor() {_x000D_
    super();_x000D_
    this.state = { value: '' };_x000D_
    this.onChange = this.onChange.bind(this);_x000D_
    this.add = this.add.bind(this);_x000D_
  }_x000D_
_x000D_
  add() {_x000D_
    this.props.onButtonClick(this.state.value);_x000D_
    this.setState({ value: '' });_x000D_
  }_x000D_
_x000D_
  onChange(e) {_x000D_
    this.setState({ value: e.target.value });_x000D_
  }_x000D_
_x000D_
  render() {_x000D_
    return (_x000D_
      <div className="add-item">_x000D_
        <input_x000D_
          type="text"_x000D_
          className="add-item__input"_x000D_
          value={this.state.value}_x000D_
          onChange={this.onChange}_x000D_
          placeholder={this.props.placeholder}_x000D_
        />_x000D_
        <button_x000D_
          disabled={!this.state.value}_x000D_
          className="add-item__button"_x000D_
          onClick={this.add}_x000D_
        >_x000D_
          Add_x000D_
        </button>_x000D_
      </div>_x000D_
    );_x000D_
  }_x000D_
}_x000D_
_x000D_
ReactDOM.render(_x000D_
  <AddItem placeholder="Value" onButtonClick={v => console.log(v)} />,_x000D_
  document.getElementById('View')_x000D_
);
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>_x000D_
<div id='View'></div>
_x000D_
_x000D_
_x000D_

CSS "color" vs. "font-color"

I would think that one reason could be that the color is applied to things other than font. For example:

div {
    border: 1px solid;
    color: red;
}

Yields both a red font color and a red border.

Alternatively, it could just be that the W3C's CSS standards are completely backwards and nonsensical as evidenced elsewhere.

How to install SignTool.exe for Windows 10

If you're using VS Express 2015, just go to your control panel --> programs and features --> select vs 2015 --> click change, then in the VS Express installer select 'Modify' --> select Publishing tools, and finish. Once setup completes the changes you will be able to create your installer.

NULL values inside NOT IN clause

Null signifies and absence of data, that is it is unknown, not a data value of nothing. It's very easy for people from a programming background to confuse this because in C type languages when using pointers null is indeed nothing.

Hence in the first case 3 is indeed in the set of (1,2,3,null) so true is returned

In the second however you can reduce it to

select 'true' where 3 not in (null)

So nothing is returned because the parser knows nothing about the set to which you are comparing it - it's not an empty set but an unknown set. Using (1, 2, null) doesn't help because the (1,2) set is obviously false, but then you're and'ing that against unknown, which is unknown.

Failed to resolve: com.android.support:appcompat-v7:28.0

implementation 'com.android.support:appcompat-v7:28.0' implementation 'com.android.support:support-media-compat:28.0.0' implementation 'com.android.support:support-v4:28.0.0' All to add

How can I get the assembly file version

See my comment above asking for clarification on what you really want. Hopefully this is it:

System.Reflection.Assembly assembly = System.Reflection.Assembly.GetExecutingAssembly();
System.Diagnostics.FileVersionInfo fvi = System.Diagnostics.FileVersionInfo.GetVersionInfo(assembly.Location);
string version = fvi.FileVersion;

The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)

I had the same problem when trying to run a PowerShell script that only looked at a remote server to read the size of a hard disk.

I turned off the Firewall (Domain networks, Private networks, and Guest or public network) on the remote server and the script worked.

I then turned the Firewall for Domain networks back on, and it worked.

I then turned the Firewall for Private network back on, and it also worked.

I then turned the Firewall for Guest or public networks, and it also worked.

AttributeError: 'DataFrame' object has no attribute

To get all the counts for all the columns in a dataframe, it's just df.count()

Storing image in database directly or as base64 data?

I came across this really great talk by Facebook engineers about the Efficient Storage of Billions of Photos in a database

plain count up timer in javascript

The following code works as a count-up timer. It's pure JavaScript code which shows hour:minute:second. It also has a STOP button:

_x000D_
_x000D_
var timerVar = setInterval(countTimer, 1000);
var totalSeconds = 0;
function countTimer() {
           ++totalSeconds;
           var hour = Math.floor(totalSeconds /3600);
           var minute = Math.floor((totalSeconds - hour*3600)/60);
           var seconds = totalSeconds - (hour*3600 + minute*60);
           if(hour < 10)
             hour = "0"+hour;
           if(minute < 10)
             minute = "0"+minute;
           if(seconds < 10)
             seconds = "0"+seconds;
           document.getElementById("timer").innerHTML = hour + ":" + minute + ":" + seconds;
        }

    
_x000D_
<div id="timer"></div>
<div id ="stop_timer" onclick="clearInterval(timerVar)">Stop time</div>
        
        
_x000D_
_x000D_
_x000D_

Can I use multiple versions of jQuery on the same page?

Taken from http://forum.jquery.com/topic/multiple-versions-of-jquery-on-the-same-page:

  • Original page loads his "jquery.versionX.js" -- $ and jQuery belong to versionX.
  • You call your "jquery.versionY.js" -- now $ and jQuery belong to versionY, plus _$ and _jQuery belong to versionX.
  • my_jQuery = jQuery.noConflict(true); -- now $ and jQuery belong to versionX, _$ and _jQuery are probably null, and my_jQuery is versionY.

How to print a groupby object

to print all (or arbitrarily many) lines of the grouped df:

import pandas as pd
pd.set_option('display.max_rows', 500)

grouped_df = df.group(['var1', 'var2'])
print(grouped_df)

Rewrite left outer join involving multiple tables from Informix to Oracle

I'm guessing that you want something like

SELECT tab1.a, tab2.b, tab3.c, tab4.d
  FROM table1 tab1 
       JOIN table2 tab2 ON (tab1.fg = tab2.fg)
       LEFT OUTER JOIN table4 tab4 ON (tab1.ss = tab4.ss)
       LEFT OUTER JOIN table3 tab3 ON (tab4.xya = tab3.xya and tab3.desc = 'XYZ')
       LEFT OUTER JOIN table5 tab5 on (tab4.kk = tab5.kk AND
                                       tab3.dd = tab5.dd)

Convert a space delimited string to list

Use string's split() method.

states.split()

JQuery style display value

If you want to check the display value, https://stackoverflow.com/a/1189281/5622596 already posted the answer.

However if instead of checking whether an element has a style of style="display:none" you want to know if that element is visible. Then use .is(":visible")

For example: $('#idDetails').is(":visible");

This will be true if it is visible & false if it is not.

How to draw a circle with text in the middle?

If it's only one line of text you could use the line-height property, with the same value as the element height:

height:100px;
line-height:100px;

If the text has multiple lines, or if the content is variable, you could use the padding-top:

padding-top:30px;
height:70px;

Example: http://jsfiddle.net/2GUFL/

jQuery: Handle fallback for failed AJAX Request

Dougs answer is correct, but you actually can use $.getJSON and catch errors (not having to use $.ajax). Just chain the getJSON call with a call to the fail function:

$.getJSON('/foo/bar.json')
    .done(function() { alert('request successful'); })
    .fail(function() { alert('request failed'); });

Live demo: http://jsfiddle.net/NLDYf/5/

This behavior is part of the jQuery.Deferred interface.
Basically it allows you to attach events to an asynchronous action after you call that action, which means you don't have to pass the event function to the action.

Read more about jQuery.Deferred here: http://api.jquery.com/category/deferred-object/

JavaScript - populate drop down list with array

Something like this should work:

var dropdown = document.getElementById("dropdown1");
if (dropdown) {
    for (var i=0; i < month.length;++i){    
        addOption(dropdown, month[i], month[i]);
    }
}

addOption = function(selectbox, text, value) {
    var optn = document.createElement("OPTION");
    optn.text = text;
    optn.value = value;
    selectbox.options.add(optn);  
}

You can refer to this article for more details:
http://www.plus2net.com/javascript_tutorial/list-adding.php

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

I had a similar error, which was fixed by adding:

Options FollowSymLinks

... in the apps/[app-name]/conf/httpd-app.conf file. This is because, in my case, an .htaccess file wants to use rewrite rules, that are not allowed with FollowSymLinks AND SymLinksIfOwnerMatch turned off.

If your conf file already has a line with Options ..., you can just add FollowSymLinks to the list of options. You could end up with something like this:

Options Indexes MultiViews FollowSymLinks

MySQL: NOT LIKE

categories_posts and categories_news start with substring 'categories_' then it is enough to check that developer_configurations_cms.cfg_name_unique starts with 'categories' instead of check if it contains the given substring. Translating all that into a query:

SELECT *
    FROM developer_configurations_cms

    WHERE developer_configurations_cms.cat_id = '1'
    AND developer_configurations_cms.cfg_variables LIKE '%parent_id=2%'
    AND developer_configurations_cms.cfg_name_unique NOT LIKE 'categories%'

How do I access properties of a javascript object if I don't know the names?

You often will want to examine the particular properties of an instance of an object, without all of it's shared prototype methods and properties:

 Obj.prototype.toString= function(){
        var A= [];
        for(var p in this){
            if(this.hasOwnProperty(p)){
                A[A.length]= p+'='+this[p];
            }
        }

    return A.join(', ');
}

Managing SSH keys within Jenkins for Git

This works for me if you have config and the private key file in the /Jenkins/.ssh/ you need to chown (change owner) for these 2 files then restart jenkins in order for the jenkins instance to read these 2 files.

Disable activity slide-in animation when launching new activity?

Apply

startActivity(new Intent(FirstActivity.this,SecondActivity.class));

then

overridePendingTransition(0, 0);

This will stop the animation.

What is a clean, Pythonic way to have multiple constructors in Python?

Use num_holes=None as a default, instead. Then check for whether num_holes is None, and if so, randomize. That's what I generally see, anyway.

More radically different construction methods may warrant a classmethod that returns an instance of cls.

ASP.NET MVC Ajax Error handling

Unfortunately, neither of answers are good for me. Surprisingly the solution is much simpler. Return from controller:

return new HttpStatusCodeResult(HttpStatusCode.BadRequest, e.Response.ReasonPhrase);

And handle it as standard HTTP error on client as you like.

How to push a single file in a subdirectory to Github (not master)

git status #then file which you need to push git add example.FileExtension

git commit "message is example"

git push -u origin(or whatever name you used) master(or name of some branch where you want to push it)

How to compare two files in Notepad++ v6.6.8

There is the "Compare" plugin. You can install it via Plugins > Plugin Manager.

Alternatively you can install a specialized file compare software like WinMerge.

How to list all users in a Linux group?

Unfortunately, there is no good, portable way to do this that I know of. If you attempt to parse /etc/group, as others are suggesting, you will miss users who have that group as their primary group and anyone who has been added to that group via a mechanism other than UNIX flat files (i.e. LDAP, NIS, pam-pgsql, etc.).

If I absolutely had to do this myself, I'd probably do it in reverse: use id to get the groups of every user on the system (which will pull all sources visible to NSS), and use Perl or something similar to maintain a hash table for each group discovered noting the membership of that user.

Edit: Of course, this leaves you with a similar problem: how to get a list of every user on the system. Since my location uses only flat files and LDAP, I can just get a list from both locations, but that may or may not be true for your environment.

Edit 2: Someone in passing reminded me that getent passwd will return a list of all users on the system including ones from LDAP/NIS/etc., but getent group still will still miss users that are members only via the default group entry, so that inspired me to write this quick hack.


#!/usr/bin/perl -T
#
# Lists members of all groups, or optionally just the group
# specified on the command line
#
# Copyright © 2010-2013 by Zed Pobre ([email protected] or [email protected])
#
# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#

use strict; use warnings;

$ENV{"PATH"} = "/usr/bin:/bin";

my $wantedgroup = shift;

my %groupmembers;
my $usertext = `getent passwd`;

my @users = $usertext =~ /^([a-zA-Z0-9_-]+):/gm;

foreach my $userid (@users)
{
    my $usergrouptext = `id -Gn $userid`;
    my @grouplist = split(' ',$usergrouptext);

    foreach my $group (@grouplist)
    {
        $groupmembers{$group}->{$userid} = 1;
    }
}

if($wantedgroup)
{
    print_group_members($wantedgroup);
}
else
{
    foreach my $group (sort keys %groupmembers)
    {
        print "Group ",$group," has the following members:\n";
        print_group_members($group);
        print "\n";
    }
}

sub print_group_members
{
    my ($group) = @_;
    return unless $group;

    foreach my $member (sort keys %{$groupmembers{$group}})
    {
        print $member,"\n";
    }
}

Convert JSON string to array of JSON objects in Javascript

Using jQuery:

var str = '{"id":1,"name":"Test1"},{"id":2,"name":"Test2"}';
var jsonObj = $.parseJSON('[' + str + ']');

jsonObj is your JSON object.

new Image(), how to know if image 100% loaded or not?

Use the load event:

img = new Image();

img.onload = function(){
  // image  has been loaded
};

img.src = image_url;

Also have a look at:

Can the :not() pseudo-class have multiple arguments?

Starting from CSS Selectors 4 using multiple arguments in the :not selector becomes possible (see here).

In CSS3, the :not selector only allows 1 selector as an argument. In level 4 selectors, it can take a selector list as an argument.

Example:

/* In this example, all p elements will be red, except for 
   the first child and the ones with the class special. */

p:not(:first-child, .special) {
  color: red;
}

Unfortunately, browser support is limited. For now, it only works in Safari.

VB.net: Date without time

Either use one of the standard date and time format strings which only specifies the date (e.g. "D" or "d"), or a custom date and time format string which only uses the date parts (e.g. "yyyy/MM/dd").

Where is the kibana error log? Is there a kibana error log?

Kibana 4 logs to stdout by default. Here is an excerpt of the config/kibana.yml defaults:

# Enables you specify a file where Kibana stores log output.
# logging.dest: stdout

So when invoking it with service, use the log capture method of that service. For example, on a Linux distribution using Systemd / systemctl (e.g. RHEL 7+):

journalctl -u kibana.service

One way may be to modify init scripts to use the --log-file option (if it still exists), but I think the proper solution is to properly configure your instance YAML file. For example, add this to your config/kibana.yml:

logging.dest: /var/log/kibana.log

Note that the Kibana process must be able to write to the file you specify, or the process will die without information (it can be quite confusing).

As for the --log-file option, I think this is reserved for CLI operations, rather than automation.

Python function global variables?

You must use the global declaration when you wish to alter the value assigned to a global variable.

You do not need it to read from a global variable. Note that calling a method on an object (even if it alters the data within that object) does not alter the value of the variable holding that object (absent reflective magic).

convert string array to string

A simple string.Concat() is what you need.

string[] test = new string[2];

test[0] = "Hello ";
test[1] = "World!";

string result = string.Concat(test);

If you also need to add a seperator (space, comma etc) then, string.Join() should be used.

string[] test = new string[2];

test[0] = "Red";
test[1] = "Blue";

string result = string.Join(",", test);

If you have to perform this on a string array with hundereds of elements than string.Join() is better by performace point of view. Just give a "" (blank) argument as seperator. StringBuilder can also be used for sake of performance, but it will make code a bit longer.

CSS: auto height on containing div, 100% height on background div inside containing div

Try excluding height from the style element.

i.e. neither give height:100% nor to any other value.

How to set custom header in Volley Request

You can see this solution. It shows how to get/set cookies, but cookies are just one of the headers in a request/response. You have to override one of the Volley's *Request classes and set the required headers in getHeaders()


Here is the linked source:

public class StringRequest extends com.android.volley.toolbox.StringRequest {

private final Map<String, String> _params;

/**
 * @param method
 * @param url
 * @param params
 *            A {@link HashMap} to post with the request. Null is allowed
 *            and indicates no parameters will be posted along with request.
 * @param listener
 * @param errorListener
 */
public StringRequest(int method, String url, Map<String, String> params, Listener<String> listener,
        ErrorListener errorListener) {
    super(method, url, listener, errorListener);

    _params = params;
}

@Override
protected Map<String, String> getParams() {
    return _params;
}

/* (non-Javadoc)
 * @see com.android.volley.toolbox.StringRequest#parseNetworkResponse(com.android.volley.NetworkResponse)
 */
@Override
protected Response<String> parseNetworkResponse(NetworkResponse response) {
    // since we don't know which of the two underlying network vehicles
    // will Volley use, we have to handle and store session cookies manually
    MyApp.get().checkSessionCookie(response.headers);

    return super.parseNetworkResponse(response);
}

/* (non-Javadoc)
 * @see com.android.volley.Request#getHeaders()
 */
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
    Map<String, String> headers = super.getHeaders();

    if (headers == null
            || headers.equals(Collections.emptyMap())) {
        headers = new HashMap<String, String>();
    }

    MyApp.get().addSessionCookie(headers);

    return headers;
}

}

And MyApp class:

public class MyApp extends Application {
    private static final String SET_COOKIE_KEY = "Set-Cookie";
    private static final String COOKIE_KEY = "Cookie";
    private static final String SESSION_COOKIE = "sessionid";

    private static MyApp _instance;
    private RequestQueue _requestQueue;
    private SharedPreferences _preferences;

    public static MyApp get() {
        return _instance;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        _instance = this;
            _preferences = PreferenceManager.getDefaultSharedPreferences(this);
        _requestQueue = Volley.newRequestQueue(this);
    }

    public RequestQueue getRequestQueue() {
        return _requestQueue;
    }


    /**
     * Checks the response headers for session cookie and saves it
     * if it finds it.
     * @param headers Response Headers.
     */
    public final void checkSessionCookie(Map<String, String> headers) {
        if (headers.containsKey(SET_COOKIE_KEY)
                && headers.get(SET_COOKIE_KEY).startsWith(SESSION_COOKIE)) {
                String cookie = headers.get(SET_COOKIE_KEY);
                if (cookie.length() > 0) {
                    String[] splitCookie = cookie.split(";");
                    String[] splitSessionId = splitCookie[0].split("=");
                    cookie = splitSessionId[1];
                    Editor prefEditor = _preferences.edit();
                    prefEditor.putString(SESSION_COOKIE, cookie);
                    prefEditor.commit();
                }
            }
    }

    /**
     * Adds session cookie to headers if exists.
     * @param headers
     */
    public final void addSessionCookie(Map<String, String> headers) {
        String sessionId = _preferences.getString(SESSION_COOKIE, "");
        if (sessionId.length() > 0) {
            StringBuilder builder = new StringBuilder();
            builder.append(SESSION_COOKIE);
            builder.append("=");
            builder.append(sessionId);
            if (headers.containsKey(COOKIE_KEY)) {
                builder.append("; ");
                builder.append(headers.get(COOKIE_KEY));
            }
            headers.put(COOKIE_KEY, builder.toString());
        }
    }

}

How to format date in angularjs

Just pass UTC date format from your server side code to client side

and use below syntax -

 {{dateUTCField  +'Z' | date : 'mm/dd/yyyy'}}

 e.g. dateUTCField = '2018-01-09T10:02:32.273' then it display like 01/09/2018

AngularJS: No "Access-Control-Allow-Origin" header is present on the requested resource

This is a server side issue. You don't need to add any headers in angular for cors. You need to add header on the server side:

Access-Control-Allow-Headers: Content-Type
Access-Control-Allow-Methods: GET, POST, OPTIONS
Access-Control-Allow-Origin: *

First two answers here: How to enable CORS in AngularJs

Switch role after connecting to database

--create a user that you want to use the database as:

create role neil;

--create the user for the web server to connect as:

create role webgui noinherit login password 's3cr3t';

--let webgui set role to neil:

grant neil to webgui; --this looks backwards but is correct.

webgui is now in the neil group, so webgui can call set role neil . However, webgui did not inherit neil's permissions.

Later, login as webgui:

psql -d some_database -U webgui
(enter s3cr3t as password)

set role neil;

webgui does not need superuser permission for this.

You want to set role at the beginning of a database session and reset it at the end of the session. In a web app, this corresponds to getting a connection from your database connection pool and releasing it, respectively. Here's an example using Tomcat's connection pool and Spring Security:

public class SetRoleJdbcInterceptor extends JdbcInterceptor {

    @Override
    public void reset(ConnectionPool connectionPool, PooledConnection pooledConnection) {

        Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

        if(authentication != null) {
            try {

                /* 
                  use OWASP's ESAPI to encode the username to avoid SQL Injection. Can't use parameters with SET ROLE. Need to write PG codec.

                  Or use a whitelist-map approach
                */
                String username = ESAPI.encoder().encodeForSQL(MY_CODEC, authentication.getName());

                Statement statement = pooledConnection.getConnection().createStatement();
                statement.execute("set role \"" + username + "\"");
                statement.close();
            } catch(SQLException exp){
                throw new RuntimeException(exp);
            }
        }
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

        if("close".equals(method.getName())){
            Statement statement = ((Connection)proxy).createStatement();
            statement.execute("reset role");
            statement.close();
        }

        return super.invoke(proxy, method, args);
    }
}

How to check sbt version?

run sbt console then type sbtVersion to check sbt version, and scalaVersion for scala version

Why am I getting string does not name a type Error?

string does not name a type. The class in the string header is called std::string.

Please do not put using namespace std in a header file, it pollutes the global namespace for all users of that header. See also "Why is 'using namespace std;' considered a bad practice in C++?"

Your class should look like this:

#include <string>

class Game
{
    private:
        std::string white;
        std::string black;
        std::string title;
    public:
        Game(std::istream&, std::ostream&);
        void display(colour, short);
};

What's the best practice using a settings file in Python?

The sample config you provided is actually valid YAML. In fact, YAML meets all of your demands, is implemented in a large number of languages, and is extremely human friendly. I would highly recommend you use it. The PyYAML project provides a nice python module, that implements YAML.

To use the yaml module is extremely simple:

import yaml
config = yaml.safe_load(open("path/to/config.yml"))

Can I have multiple primary keys in a single table?

You can only have one primary key, but you can have multiple columns in your primary key.

You can also have Unique Indexes on your table, which will work a bit like a primary key in that they will enforce unique values, and will speed up querying of those values.

Maximum Length of Command Line String

In Windows 10, it's still 8191 characters...at least on my machine.

It just cuts off any text after 8191 characters. Well, actually, I got 8196 characters, and after 8196, then it just won't let me type any more.

Here's a script that will test how long of a statement you can use. Well, assuming you have gawk/awk installed.

echo rem this is a test of how long of a line that a .cmd script can generate >testbat.bat
gawk 'BEGIN {printf "echo -----";for (i=10;i^<=100000;i +=10) printf "%%06d----",i;print;print "pause";}' >>testbat.bat
testbat.bat

Why do people hate SQL cursors so much?

Cursors make people overly apply a procedural mindset to a set-based environment.

And they are SLOW!!!

From SQLTeam:

Please note that cursors are the SLOWEST way to access data inside SQL Server. The should only be used when you truly need to access one row at a time. The only reason I can think of for that is to call a stored procedure on each row. In the Cursor Performance article I discovered that cursors are over thirty times slower than set based alternatives.

If input field is empty, disable submit button

Try this code

$(document).ready(function(){
    $('.sendButton').attr('disabled',true);

    $('#message').keyup(function(){
        if($(this).val().length !=0){
            $('.sendButton').attr('disabled', false);
        }
        else
        {
            $('.sendButton').attr('disabled', true);        
        }
    })
});

Check demo Fiddle

You are missing the else part of the if statement (to disable the button again if textbox is empty) and parentheses () after val function in if($(this).val.length !=0){

Java Ordered Map

I think the closest collection you'll get from the framework is the SortedMap

How to convert a byte array to Stream

I am using as what John Rasch said:

Stream streamContent = taxformUpload.FileContent;

how does multiplication differ for NumPy Matrix vs Array classes?

There is a situation where the dot operator will give different answers when dealing with arrays as with dealing with matrices. For example, suppose the following:

>>> a=numpy.array([1, 2, 3])
>>> b=numpy.array([1, 2, 3])

Lets convert them into matrices:

>>> am=numpy.mat(a)
>>> bm=numpy.mat(b)

Now, we can see a different output for the two cases:

>>> print numpy.dot(a.T, b)
14
>>> print am.T*bm
[[1.  2.  3.]
 [2.  4.  6.]
 [3.  6.  9.]]

NSAttributedString add text alignment

Swift 4.0+

let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center

let titleFont = UIFont.preferredFont(forTextStyle: UIFontTextStyle.headline)
let title = NSMutableAttributedString(string: "You Are Registered", 
    attributes: [.font: titleFont,    
    .foregroundColor: UIColor.red, 
    .paragraphStyle: titleParagraphStyle])

Swift 3.0+

let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .center

let titleFont = UIFont.preferredFont(forTextStyle: UIFontTextStyle.headline)
let title = NSMutableAttributedString(string: "You Are Registered", 
    attributes: [NSFontAttributeName:titleFont,    
    NSForegroundColorAttributeName:UIColor.red, 
    NSParagraphStyleAttributeName: titleParagraphStyle])

(original answer below)

Swift 2.0+

let titleParagraphStyle = NSMutableParagraphStyle()
titleParagraphStyle.alignment = .Center

let titleFont = UIFont.preferredFontForTextStyle(UIFontTextStyleHeadline)
let title = NSMutableAttributedString(string: "You Are Registered",
    attributes:[NSFontAttributeName:titleFont,   
    NSForegroundColorAttributeName:UIColor.redColor(), 
    NSParagraphStyleAttributeName: titleParagraphStyle])

java.lang.ClassNotFoundException: org.apache.xmlbeans.XmlObject Error

You need to include xmlbeans-xxx.jar and if you have downloaded the POI binary zip, you will get the xmlbeans-xxx.jar in ooxml-lib folder (eg: \poi-3.11\ooxml-lib)

This jar is used for XML binding which is applicable for .xlsx files.

Code for a simple JavaScript countdown timer?

Just modified @ClickUpvote's answer:

You can use IIFE (Immediately Invoked Function Expression) and recursion to make it a little bit more easier:

var i = 5;  //set the countdown
(function timer(){
    if (--i < 0) return;
    setTimeout(function(){
        console.log(i + ' secs');  //do stuff here
        timer();
    }, 1000);
})();

_x000D_
_x000D_
var i = 5;_x000D_
(function timer(){_x000D_
    if (--i < 0) return;_x000D_
    setTimeout(function(){_x000D_
        document.getElementsByTagName('h1')[0].innerHTML = i + ' secs';_x000D_
        timer();_x000D_
    }, 1000);_x000D_
})();
_x000D_
<h1>5 secs</h1>
_x000D_
_x000D_
_x000D_

How to remove array element in mongodb?

If you use the Mongoose API and looking to pull a sub/child object: Read this document Don't forget to use save() when you're done editing otherwise the changes won't be saved to the database.

How to change option menu icon in the action bar?

//just edit menu.xml file    
//add icon for item which will change default setting icon
//add sub menus


 ///menu.xml file


    <item
            android:id="@+id/action_settings"
            android:orderInCategory="100"
            android:title="@string/action_settings"
            android:icon="@drawable/your_icon"
            app:showAsAction="always" >

            <menu>

                <item android:id="@+id/action_menu1"
                    android:icon="@android:drawable/ic_menu_preferences"
                    android:title="menu 1" />

                <item android:id="@+id/action_menu2"
                    android:icon="@android:drawable/ic_menu_help"
                    android:title="menu 2" />

            </menu>
        </item>

SSRS expression to format two decimal places does not show zeros

Please try the following code snippet,

IIF(Round(Avg(Fields!Vision_Score.Value)) = Avg(Fields!Vision_Score.Value), 
Format(Avg(Fields!Vision_Score.Value)), 
FORMAT(Avg(Fields!Vision_Score.Value),"##.##"))

hope it will help, Thank-you.