Programs & Examples On #Db4o

db4o is an open source embeddable object database for Java and .NET.

MySQL config file location - redhat linux server

The information you want can be found by running

mysql --help

or

mysqld --help --verbose

I tried this :

    mysql --help | grep Default -A 1

And the output:

                      (Defaults to on; use --skip-auto-rehash to disable.)
  -A, --no-auto-rehash 
--
                      (Defaults to on; use --skip-line-numbers to disable.)
  -L, --skip-line-numbers 
--
                      (Defaults to on; use --skip-column-names to disable.)
  -N, --skip-column-names 
--
                      (Defaults to on; use --skip-reconnect to disable.)
  -s, --silent        Be more silent. Print results with a tab as separator,
--
  --default-auth=name Default authentication client-side plugin to use.
  --binary-mode       By default, ASCII '\0' is disallowed and '\r\n' is
--
Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /usr/etc/my.cnf ~/.my.cnf 

Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x)

Seems like the list of fixes is growing, even years after since the original question.

Below is the full list for Windows (so far as of circa 02/2020)


If you have Windows 10, with all updates installed and you believe

  • Hyper-V is disabled
  • Microsoft Defender's Memory Integrity/Core Isolation is disabled
  • Antivirus is disabled

try Step 6 below. It is likely the cause.

Also to see if your fix worked, you can manually download the Intel HAXM installer here. (Latest version of HAXM may not be the same as what comes from Android Studio) Before starting the install, run the haxm_check.exe included in the download from command line. If your fix worked, it should show yes for both NX and VT.

If you just double click haxm_check.exe you won't see anything. Run it from cmd or powershell to see the output.


  1. Check BIOS
  • go into BIOS/UEFI setup and look for settings like
    • VT-x
    • VT-d
    • Virtualization Technology
    • Hardware Virtualization

make sure it is Enabled. If the option is not there, check with your manufacturer and model to make sure it is supported.

  1. Disable Hyper-V
  • Type 'windows features' into start menu, select 'Turn Windows Features On or Off'.
  • Unselect all Hyper-V related options, press OK, Reboot.
  • This will break any Hyper-V VMs you have, including any Windows Phone emulators and anything else you have setup that requires Hyper-V
  • Reboot Required
  • on an admin command prompt, run systeminfo. If it shows 'hypervisor is detected' under Hyper-V requirements, even after removing Hyper-V feature, you may have 'Core Isolation' enabled. See below on how to disable it.
  • As another option, try enabling 'Windows Hypervisor Platform' if you still want your Hyper-V support. More info here
  1. AMD Ryzen ?
  • If your CPU is AMD Ryzen, you may need to enable 'Windows Hypervisor Platform' feature just like you disabled Hyper-V above.
  • If it is enabled and still things don't work, try disabling it. ¯\(?)
  • Reboot required
  1. Disable Antivirus
  • Try disabling your antivirus.
  • AVAST! and a few others interfere with the detection of virtualization. You can enable them after.
  • AVAST and some others also has some options that uses virtualization based isolation. Either disable them or temporally uninstall your AV.
  1. Disable Core Isolation
  • Clean installs of Windows 10 1803 enables Core Isolation by default, which runs secure processes inside a virtualized container for security. This interferes with the detection of virtualization.
  • Machines that upgraded from an earlier version have this disabled, but check anyway.
  • Go to Windows Defender Security Center
  • Device Security > Core Isolation > details
  • Disable Memory Integrity
  • Reboot

  1. Disable hypervisor launch at boot
  • on an admin command prompt, run bcdedit /set hypervisorlaunchtype off
  • reboot
  • to revert run bcdedit /set hypervisorlaunchtype auto and reboot
  • You can probably set it to auto after the emulator has installed. But may need to set to off reboot the next time you create an emulator/download and install an emulator image.

  1. Nothing works
  • You shouldn't get here, since Android emulator can now run alongside with Hyper-V if you have 'Windows Hypervisor Platform' is enabled.
  • If nothing above works, as a last resort you can try running Android in a Hyper-V VM and get ADB to connect to it. (Not a solution, but a workaround)
  • You can also run android using a third-party emulator like Genimotion.
  1. ¯\(?)

Edits/New fixes welcome.

hope this helps

How to make fixed header table inside scrollable div?

This code works form me. Include the jquery.js file.

<!DOCTYPE html>
<html>

<head>
<script src="jquery.js"></script>
<script>
var headerDivWidth=0;
var contentDivWidth=0;
function fixHeader(){

var contentDivId = "contentDiv";
var headerDivId = "headerDiv";

var header = document.createElement('table');
var headerRow = document.getElementById('tableColumnHeadings'); 

/*Start : Place header table inside <DIV> and place this <DIV> before content table*/
var headerDiv = "<div id='"+headerDivId+"' style='width:500px;overflow-x:hidden;overflow-y:scroll' class='tableColumnHeadings'><table></table></div>";
$(headerRow).wrap(headerDiv);
$("#"+headerDivId).insertBefore("#"+contentDivId);
/*End : Place header table inside <DIV> and place this <DIV> before content table*/

fixColumnWidths(headerDivId,contentDivId);
}
function fixColumnWidths(headerDivId,contentDivId){
 /*Start : Place header row cell and content table first row cell inside <DIV>*/ 
            var contentFirstRowCells = $('#'+contentDivId+' table tr:first-child td');
            for (k = 0; k < contentFirstRowCells.length; k++) {
                $( contentFirstRowCells[k] ).wrapInner( "<div ></div>");
            }
            var headerFirstRowCells = $('#'+headerDivId+' table tr:first-child td');
            for (k = 0; k < headerFirstRowCells.length; k++) {
                $( headerFirstRowCells[k] ).wrapInner( "<div></div>");
            }
 /*End : Place header row cell and content table first row cell inside <DIV>*/ 

 /*Start : Fix width for columns of header cells and content first ror cells*/
            var headerColumns = $('#'+headerDivId+' table tr:first-child td div:first-child');
            var contentColumns = $('#'+contentDivId+' table tr:first-child td div:first-child');
            for (i = 0; i < contentColumns.length; i++) {
                if (i == contentColumns.length - 1) {
                    contentCellWidth = contentColumns[i].offsetWidth;
                }
                else {
                    contentCellWidth = contentColumns[i].offsetWidth;
                }
                headerCellWidth = headerColumns[i].offsetWidth;
                if(contentCellWidth>headerCellWidth){
                $(headerColumns[i]).css('width', contentCellWidth+"px");
                $(contentColumns[i]).css('width', contentCellWidth+"px");
                }else{
                $(headerColumns[i]).css('width', headerCellWidth+"px");
                $(contentColumns[i]).css('width', headerCellWidth+"px");
                }
            }
/*End : Fix width for columns of header and columns of content table first row*/
}   

    function OnScrollDiv(Scrollablediv) {
    document.getElementById('headerDiv').scrollLeft = Scrollablediv.scrollLeft;
    }
function radioCount(){
    alert(document.form.elements.length);

}   
</script>
<style>
table,th,td
{
border:1px solid black;
border-collapse:collapse;
}
th,td
{
padding:5px;
}
</style>

</head>

<body onload="fixHeader();">
<form id="form" name="form">
<div id="contentDiv" style="width:500px;height:100px;overflow:auto;" onscroll="OnScrollDiv(this)">
<table>
<!--tr id="tableColumnHeadings" class="tableColumnHeadings">
  <td><div>Firstname</div></td>
  <td><div>Lastname</div></td>      
  <td><div>Points</div></td>
  </tr>

<tr>
  <td><div>Jillsddddddddddddddddddddddddddd</div></td>
  <td><div>Smith</div></td>     
  <td><div>50</div></td>
  </tr-->

  <tr id="tableColumnHeadings" class="tableColumnHeadings">
  <td>&nbsp;</td>

  <td>Firstname</td>
  <td>Lastname</td>     
  <td>Points</td>
  </tr>

<tr style="height:0px">
<td></td>
  <td></td>
  <td></td>     
  <td></td>
  </tr>

<tr >
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID" onclick="javascript:radioCount();"/></td>
  <td>Jillsddddddddddddddddddddddddddd</td>
  <td>Smith</td>        
  <td>50</td>
  </tr>

<tr>
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID"/></td>

  <td>Eve</td>
  <td>Jackson</td>      
  <td>9400000000000000000000000000000</td>
</tr>
<tr>
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID"/></td>

  <td>John</td>
  <td>Doe</td>      
  <td>80</td>
</tr>
<tr>
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID"/></td>

  <td><div>Jillsddddddddddddddddddddddddddd</div></td>
  <td><div>Smith</div></td>     
  <td><div>50</div></td>
  </tr>
<tr>
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID"/></td>

  <td>Eve</td>
  <td>Jackson</td>      
  <td>9400000000000000000000000000000</td>
</tr>
<tr>
<td><input type="radio" id="SELECTED_ID" name="SELECTED_ID"/></td>

  <td>John</td>
  <td>Doe</td>      
  <td>80</td>
</tr>
</table>
</div>

</form>
</body>

</html>

Numpy array dimensions

It is .shape:

ndarray.shape
Tuple of array dimensions.

Thus:

>>> a.shape
(2, 2)

Setting Windows PATH for Postgres tools

Set path For PostgreSQL in Windows:

  1. Searching for env will show Edit environment variables for your account
  2. Select Environment Variables
  3. From the System Variables box select PATH
  4. Click New (to add new path)

Change the PATH variable to include the bin directory of your PostgreSQL installation.
then add new path their....[for example]

C:\Program Files\PostgreSQL\12\bin

After that click OK

Open CMD/Command Prompt. Type this to open psql

psql -U username database_name

For Example psql -U postgres test

Now, you will be prompted to give Password for the User. (It will be hidden as a security measure).

Then you are good to go.

How to sort the files according to the time stamp in unix?

File modification:

ls -t

Inode change:

ls -tc

File access:

ls -tu

"Newest" one at the bottom:

ls -tr

None of this is a creation time. Most Unix filesystems don't support creation timestamps.

Getting NetworkCredential for current user (C#)

If the web service being invoked uses windows integrated security, creating a NetworkCredential from the current WindowsIdentity should be sufficient to allow the web service to use the current users windows login. However, if the web service uses a different security model, there isn't any way to extract a users password from the current identity ... that in and of itself would be insecure, allowing you, the developer, to steal your users passwords. You will likely need to provide some way for your user to provide their password, and keep it in some secure cache if you don't want them to have to repeatedly provide it.

Edit: To get the credentials for the current identity, use the following:

Uri uri = new Uri("http://tempuri.org/");
ICredentials credentials = CredentialCache.DefaultCredentials;
NetworkCredential credential = credentials.GetCredential(uri, "Basic");

How to convert PDF files to images

As for 2018 there is still not a simple answer to the question of how to convert a PDF document to an image in C#; many libraries use Ghostscript licensed under AGPL and in most cases an expensive commercial license is required for production use.

A good alternative might be using the popular 'pdftoppm' utility which has a GPL license; it can be used from C# as command line tool executed with System.Diagnostics.Process. Popular tools are well known in the Linux world, but a windows build is also available.

If you don't want to integrate pdftoppm by yourself, you can use my PdfRenderer popular wrapper (supports both classic .NET Framework and .NET Core) - it is not free, but pricing is very affordable.

Cannot open Windows.h in Microsoft Visual Studio

1) Go to C:\Program Files (x86)\Microsoft SDKs\Windows\v7.1A for VS2013

2) Copy the folders Include and Lib (you should check where are your folders in folder windows such as v7.1, v8, v6, etc.)

3) Paste them into C:\Program Files (x86)\Microsoft Visual Studio 12.0\VC

I solved my problems like:

error lnk1104: cannot open file 'kernel32.lib'.
error c1083: Cannot open Windows.h

Thanks.

How do you get a query string on Flask?

from flask import request

@app.route('/data')
def data():
    # here we want to get the value of user (i.e. ?user=some-value)
    user = request.args.get('user')

Python - Extracting and Saving Video Frames

From here download this video so we have the same video file for the test. Make sure to have that mp4 file in the same directory of your python code. Then also make sure to run the python interpreter from the same directory.

Then modify the code, ditch waitKey that's wasting time also without a window it cannot capture the keyboard events. Also we print the success value to make sure it's reading the frames successfully.

import cv2
vidcap = cv2.VideoCapture('big_buck_bunny_720p_5mb.mp4')
success,image = vidcap.read()
count = 0
while success:
  cv2.imwrite("frame%d.jpg" % count, image)     # save frame as JPEG file      
  success,image = vidcap.read()
  print('Read a new frame: ', success)
  count += 1

How does that go?

Select distinct rows from datatable in Linq

If it's not a typed dataset, then you probably want to do something like this, using the Linq-to-DataSet extension methods:

var distinctValues = dsValues.AsEnumerable()
                        .Select(row => new {
                            attribute1_name = row.Field<string>("attribute1_name"),
                            attribute2_name = row.Field<string>("attribute2_name")
                         })
                        .Distinct();

Make sure you have a using System.Data; statement at the beginning of your code in order to enable the Linq-to-Dataset extension methods.

Hope this helps!

How to parse a CSV file using PHP

A bit shorter answer since PHP >= 5.3.0:

    $csvFile = file('../somefile.csv');
    $data = [];
    foreach ($csvFile as $line) {
        $data[] = str_getcsv($line);
    }

Get the current file name in gulp.src()

I'm not sure how you want to use the file names, but one of these should help:

  • If you just want to see the names, you can use something like gulp-debug, which lists the details of the vinyl file. Insert this anywhere you want a list, like so:

    var gulp = require('gulp'),
        debug = require('gulp-debug');
    
    gulp.task('examples', function() {
        return gulp.src('./examples/*.html')
            .pipe(debug())
            .pipe(gulp.dest('./build'));
    });
    
  • Another option is gulp-filelog, which I haven't used, but sounds similar (it might be a bit cleaner).

  • Another options is gulp-filesize, which outputs both the file and it's size.

  • If you want more control, you can use something like gulp-tap, which lets you provide your own function and look at the files in the pipe.

Remove whitespaces inside a string in javascript

Probably because you forgot to implement the solution in the accepted answer. That's the code that makes trim() work.

update

This answer only applies to older browsers. Newer browsers apparently support trim() natively.

Javascript to set hidden form value on drop down change

<form>
  <input type="hidden" name="selval">
  <select onchange="this.form.selval.value=this.selectedIndex">
    <option>val1</option>
    <option>val2</option>
  </select>
</form>

pure javascript from within a form

What is default color for text in textview?

I believe the default color integer value is 16711935 (0x00FF00FF).

Make cross-domain ajax JSONP request with jQuery

you need to parse your xml with jquery json parse...i.e

  var parsed_json = $.parseJSON(xml);

jQuery - find child with a specific class

Based on your comment, moddify this:

$( '.bgHeaderH2' ).html (); // will return whatever is inside the DIV

to:

$( '.bgHeaderH2', $( this ) ).html (); // will return whatever is inside the DIV

More about selectors: https://api.jquery.com/category/selectors/

How to get last month/year in java?

private static String getPreviousMonthDate(Date date){
    final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");

    Calendar cal = Calendar.getInstance();  
    cal.setTime(date);  
    cal.set(Calendar.DAY_OF_MONTH, 1);  
    cal.add(Calendar.DATE, -1);

    Date preMonthDate = cal.getTime();  
    return format.format(preMonthDate);
}


private static String getPreToPreMonthDate(Date date){
    final SimpleDateFormat format = new SimpleDateFormat("dd-MM-yyyy");

    Calendar cal = Calendar.getInstance();  
    cal.setTime(date);  
    cal.add(Calendar.MONTH, -1);  
    cal.set(Calendar.DAY_OF_MONTH,1);  
    cal.add(Calendar.DATE, -1);  

    Date preToPreMonthDate = cal.getTime();  
    return format.format(preToPreMonthDate);
}

Eclipse does not start when I run the exe?

I tried everything except this. After rigorous trials,Uninstalling java 8 update 25 helped me.

Extract Month and Year From Date in R

Here's another solution using a package solely dedicated to working with dates and times in R:

library(tidyverse)
library(lubridate)

(df <- tibble(ID = 1:3, Date = c("2004-02-06" , "2006-03-14", "2007-07-16")))
#> # A tibble: 3 x 2
#>      ID Date      
#>   <int> <chr>     
#> 1     1 2004-02-06
#> 2     2 2006-03-14
#> 3     3 2007-07-16

df %>%
  mutate(
    Date = ymd(Date),
    Month_Yr = format_ISO8601(Date, precision = "ym")
  )
#> # A tibble: 3 x 3
#>      ID Date       Month_Yr
#>   <int> <date>     <chr>   
#> 1     1 2004-02-06 2004-02 
#> 2     2 2006-03-14 2006-03 
#> 3     3 2007-07-16 2007-07

Created on 2020-09-01 by the reprex package (v0.3.0)

How can I have two fixed width columns with one flexible column in the center?

Despite setting up dimensions for the columns, they still seem to shrink as the window shrinks.

An initial setting of a flex container is flex-shrink: 1. That's why your columns are shrinking.

It doesn't matter what width you specify (it could be width: 10000px), with flex-shrink the specified width can be ignored and flex items are prevented from overflowing the container.

I'm trying to set up a flexbox with 3 columns where the left and right columns have a fixed width...

You will need to disable shrinking. Here are some options:

.left, .right {
     width: 230px;
     flex-shrink: 0;
 }  

OR

.left, .right {
     flex-basis: 230px;
     flex-shrink: 0;
}

OR, as recommended by the spec:

.left, .right {
    flex: 0 0 230px;    /* don't grow, don't shrink, stay fixed at 230px */
}

7.2. Components of Flexibility

Authors are encouraged to control flexibility using the flex shorthand rather than with its longhand properties directly, as the shorthand correctly resets any unspecified components to accommodate common uses.

More details here: What are the differences between flex-basis and width?

An additional thing I need to do is hide the right column based on user interaction, in which case the left column would still keep its fixed width, but the center column would fill the rest of the space.

Try this:

.center { flex: 1; }

This will allow the center column to consume available space, including the space of its siblings when they are removed.

Revised Fiddle

How do I find Waldo with Mathematica?

I have a quick solution for finding Waldo using OpenCV.

I used the template matching function available in OpenCV to find Waldo.

To do this a template is needed. So I cropped Waldo from the original image and used it as a template.

enter image description here

Next I called the cv2.matchTemplate() function along with the normalized correlation coefficient as the method used. It returned a high probability at a single region as shown in white below (somewhere in the top left region):

enter image description here

The position of the highest probable region was found using cv2.minMaxLoc() function, which I then used to draw the rectangle to highlight Waldo:

enter image description here

How to retrieve unique count of a field using Kibana + Elastic Search

Now Kibana 4 allows you to use aggregations. Apart from building a panel like the one that was explained in this answer for Kibana 3, now we can see the number of unique IPs in different periods, that was (IMO) what the OP wanted at the first place.

To build a dashboard like this you should go to Visualize -> Select your Index -> Select a Vertical Bar chart and then in the visualize panel:

  • In the Y axis we want the unique count of IPs (select the field where you stored the IP) and in the X axis we want a date histogram with our timefield.

Building a visualization

  • After pressing the Apply button, we should have a graph that shows the unique count of IP distributed on time. We can change the time interval on the X axis to see the unique IPs hourly/daily...

Final plot

Just take into account that the unique counts are approximate. For more information check also this answer.

How to get single value from this multi-dimensional PHP array

You can also use array_column(). It's available from PHP 5.5: php.net/manual/en/function.array-column.php

It returns the values from a single column of the array, identified by the column_key. Optionally, you may provide an index_key to index the values in the returned array by the values from the index_key column in the input array.

print_r(array_column($myarray, 'email'));

Escape double quotes in Java

Yes you will have to escape all double quotes by a backslash.

set up device for development (???????????? no permissions)

Nothing worked for me until I finally found the answer here: http://ptspts.blogspot.co.il/2011/10/how-to-fix-adb-no-permissions-error-on.html

I'm copying the text here in case it disappears in the future.

Create a file named /tmp/android.rules with the following contents (hex vendor numbers were taken from the vendor list page):

SUBSYSTEM=="usb", ATTRS{idVendor}=="0bb4", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0e79", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0502", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0b05", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="413c", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0489", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="091e", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="18d1", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0bb4", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="12d1", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="24e3", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="2116", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0482", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="17ef", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1004", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="22b8", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0409", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="2080", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0955", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="2257", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="10a9", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1d4d", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0471", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="04da", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="05c6", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1f53", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="04e8", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="04dd", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0fce", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="0930", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="19d2", MODE="0666"
SUBSYSTEM=="usb", ATTRS{idVendor}=="1bbb", MODE="0666"

Run the following commands:

sudo cp /tmp/android.rules /etc/udev/rules.d/51-android.rules
sudo chmod 644   /etc/udev/rules.d/51-android.rules
sudo chown root. /etc/udev/rules.d/51-android.rules
sudo service udev restart
sudo killall adb

Disconnect the USB cable between the phone and the computer.

Reconnect the phone.

Run adb devices to confirm that now it has permission to access the phone.

Please note that it's possible to use , USER="$LOGINNAME" instead of , MODE="0666" in the .rules file, substituting $LOGINNAME for your login name, i.e. what id -nu prints.

In some cases it can be necessary to give the udev rules file a name that sorts close to the end, such as z51-android.rules.

What do the python file extensions, .pyc .pyd .pyo stand for?

  • .py - Regular script
  • .py3 - (rarely used) Python3 script. Python3 scripts usually end with ".py" not ".py3", but I have seen that a few times
  • .pyc - compiled script (Bytecode)
  • .pyo - optimized pyc file (As of Python3.5, Python will only use pyc rather than pyo and pyc)
  • .pyw - Python script to run in Windowed mode, without a console; executed with pythonw.exe
  • .pyx - Cython src to be converted to C/C++
  • .pyd - Python script made as a Windows DLL
  • .pxd - Cython script which is equivalent to a C/C++ header
  • .pxi - MyPy stub
  • .pyi - Stub file (PEP 484)
  • .pyz - Python script archive (PEP 441); this is a script containing compressed Python scripts (ZIP) in binary form after the standard Python script header
  • .pywz - Python script archive for MS-Windows (PEP 441); this is a script containing compressed Python scripts (ZIP) in binary form after the standard Python script header
  • .py[cod] - wildcard notation in ".gitignore" that means the file may be ".pyc", ".pyo", or ".pyd".
  • .pth - a path configuration file; its contents are additional items (one per line) to be added to sys.path. See site module.

A larger list of additional Python file-extensions (mostly rare and unofficial) can be found at http://dcjtech.info/topic/python-file-extensions/

Show hide fragment in android

Hi you do it by using this approach, all fragments will remain in the container once added initially and then we are simply revealing the desired fragment and hiding the others within the container.

// Within an activity
private FragmentA fragmentA;
private FragmentB fragmentB;
private FragmentC fragmentC;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    if (savedInstanceState == null) {
        fragmentA = FragmentA.newInstance("foo");
        fragmentB = FragmentB.newInstance("bar");
        fragmentC = FragmentC.newInstance("baz");
    }
}


// Replace the switch method
protected void displayFragmentA() {
    FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
    if (fragmentA.isAdded()) { // if the fragment is already in container
        ft.show(fragmentA);
    } else { // fragment needs to be added to frame container
        ft.add(R.id.flContainer, fragmentA, "A");
    }
    // Hide fragment B
    if (fragmentB.isAdded()) { ft.hide(fragmentB); }
    // Hide fragment C
    if (fragmentC.isAdded()) { ft.hide(fragmentC); }
    // Commit changes
    ft.commit();
}

Please see https://github.com/codepath/android_guides/wiki/Creating-and-Using-Fragments for more info. I hope I get to help anyone. Even if it this is an old question.

SQL User Defined Function Within Select

Use a scalar-valued UDF, not a table-value one, then you can use it in a SELECT as you want.

Using ORDER BY and GROUP BY together

SQL>

SELECT interview.qtrcode QTR, interview.companyname "Company Name", interview.division Division 
FROM interview 
JOIN jobsdev.employer 
    ON (interview.companyname = employer.companyname AND employer.zipcode like '100%')
GROUP BY interview.qtrcode, interview.companyname, interview.division
ORDER BY interview.qtrcode;

Importing xsd into wsdl

You have a couple of problems here.

First, the XSD has an issue where an element is both named or referenced; in your case should be referenced.

Change:

<xsd:element name="stock" ref="Stock" minOccurs="1" maxOccurs="unbounded"/> 

To:

<xsd:element name="stock" type="Stock" minOccurs="1" maxOccurs="unbounded"/> 

And:

  • Remove the declaration of the global element Stock
  • Create a complex type declaration for a type named Stock

So:

<xsd:element name="Stock">
    <xsd:complexType>

To:

<xsd:complexType name="Stock">

Make sure you fix the xml closing tags.

The second problem is that the correct way to reference an external XSD is to use XSD schema with import/include within a wsdl:types element. wsdl:import is reserved to referencing other WSDL files. More information is available by going through the WS-I specification, section WSDL and Schema Import. Based on WS-I, your case would be:

INCORRECT: (the way you showed it)

<?xml version="1.0" encoding="UTF-8"?>
<definitions targetNamespace="http://stock.com/schemas/services/stock/wsdl"
    .....xmlns:external="http://stock.com/schemas/services/stock"
    <import namespace="http://stock.com/schemas/services/stock" location="Stock.xsd" />
    <message name="getStockQuoteResp">
        <part name="parameters" element="external:getStockQuoteResponse" />
    </message>
</definitions>

CORRECT:

<?xml version="1.0" encoding="UTF-8"?>
<definitions targetNamespace="http://stock.com/schemas/services/stock/wsdl"
    .....xmlns:external="http://stock.com/schemas/services/stock"
    <types>
        <schema xmlns="http://www.w3.org/2001/XMLSchema">
            <import namespace="http://stock.com/schemas/services/stock" schemaLocation="Stock.xsd" />             
        </schema>
    </types>
    <message name="getStockQuoteResp">
        <part name="parameters" element="external:getStockQuoteResponse" />
    </message>
</definitions>

SOME processors may support both syntaxes. The XSD you put out shows issues, make sure you first validate the XSD.

It would be better if you go the WS-I way when it comes to WSDL authoring.

Other issues may be related to the use of relative vs. absolute URIs in locating external content.

Get UserDetails object from Security Context in Spring MVC controller

You can use below code to find out principal (user email who logged in)

  org.opensaml.saml2.core.impl.NameIDImpl principal =  
  (NameIDImpl) SecurityContextHolder.getContext().getAuthentication().getPrincipal();

  String email = principal.getValue();

This code is written on top of SAML.

What size should apple-touch-icon.png be for iPad and iPhone?

Updated list December 2019, iOS13 One icon for iOS 180x180 px and one for android 192x192 px (declared in site.webmanifest).

<link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png">
<link rel="manifest" href="/site.webmanifest">
#### site.webmanifest
{
    "name": "",
    "short_name": "",
    "icons": [
        {
            "src": "/android-chrome-192x192.png",
            "sizes": "192x192",
            "type": "image/png"
        }
    ],
    "display": "standalone"
}

Deprecated list October 2017, iOS11

List for iPhone and iPad with and without retina

<!-- iPhone(first generation or 2G), iPhone 3G, iPhone 3GS -->
<link rel="apple-touch-icon" sizes="57x57" href="touch-icon-iphone.png">
<!-- iPad and iPad mini @1x -->
<link rel="apple-touch-icon" sizes="76x76" href="touch-icon-ipad.png">
<!-- iPhone 4, iPhone 4s, iPhone 5, iPhone 5c, iPhone 5s, iPhone 6, iPhone 6s, iPhone 7, iPhone 7s, iPhone8 -->
<link rel="apple-touch-icon" sizes="120x120" href="touch-icon-iphone-retina.png">
<!-- iPad and iPad mini @2x -->
<link rel="apple-touch-icon" sizes="152x152" href="touch-icon-ipad-retina.png">
<!-- iPad Pro -->
<link rel="apple-touch-icon" sizes="167x167" href="touch-icon-ipad-pro.png">
<!-- iPhone X, iPhone 8 Plus, iPhone 7 Plus, iPhone 6s Plus, iPhone 6 Plus -->
<link rel="apple-touch-icon" sizes="180x180" href="touch-icon-iphone-6-plus.png">
<!-- Android Devices High Resolution -->
<link rel="icon" sizes="192x192" href="icon-hd.png">
<!-- Android Devices Normal Resolution -->
<link rel="icon" sizes="128x128" href="icon.png">

Update Oct 2017 iOS 11: iOS 11 checked, iPhone X and iPhone 8 introduced

Update Nov 2016 iOS 10: New iOS version iPhone 7 and iPhone 7plus introduced, they have the same display resolution, dpi, etc as iPhone 6s and iPhone 7plus, until now no changes found respecting the update 2015

Update Mid 2016 Android: Add Android Devices to the list as the apple-touch links are marked as deprecated by Google and will be not supported anytime for their devices

<!-- Android Devices High Resolution -->
<link rel="icon" sizes="192x192" href="icon-hd.png">
<!-- Android Devices High Resolution -->
<link rel="icon" sizes="128x128" href="icon.png">

Update 2015 iOS 9: For iOS 9 and iPad pro

<link rel="apple-touch-icon" sizes="167x167" href="touch-icon-ipad-pro.png">

The new iPhones (6s and 6s Plus) are using the same sizes as the iPhone(6 and 6 Plus), the new iPad pro uses an image of size 167x167 px, the other resolutions are still the same.

Update 2014 iOS 8:

For iOS 8 and iPhone 6 plus

<link rel="apple-touch-icon" sizes="180x180" href="touch-icon-iphone-6-plus.png"> 

Iphone 6 uses the same 120 x 120 px image as iphone 4 and 5 the rest is the same as for iOS 7

Update 2013 iOS7:

For iOS 7 the recommended resolutions changed:

  • for iPhone Retina from 114 x 114 px to 120 x 120 px
  • for iPad Retina from 144 x 144 px to 152 x 152 px

The other resolution are still the same

  • 57 x 57 px default
  • 76 x 76 px for iPads without retina

Source: https://developer.apple.com/ios/human-interface-guidelines/icons-and-images/app-icon/

How to properly express JPQL "join fetch" with "where" clause as JPA 2 CriteriaQuery?

I will show visually the problem, using the great example from James answer and adding the alternative solution.

When you do the follow query, without the FETCH:

Select e from Employee e 
join e.phones p 
where p.areaCode = '613'

You will have the follow results from Employee as you expected:

EmployeeId EmployeeName PhoneId PhoneAreaCode
1 James 5 613
1 James 6 416

But when you add the FETCH word on JOIN, this is what happens:

EmployeeId EmployeeName PhoneId PhoneAreaCode
1 James 5 613

The generated SQL is the same for the two queries, but the Hibernate removes on memory the 416 register when you use WHERE on the FETCH join.

So, to bring all phones and apply the WHERE correctly, you need to have two JOINs: one for the WHERE and another for the FETCH. Like:

Select e from Employee e 
join e.phones p 
join fetch e.phones      //no alias, to not commit the mistake
where p.areaCode = '613'

How to scroll to the bottom of a RecyclerView? scrollToPosition doesn't work

In Kotlin:

recyclerView.viewTreeObserver.addOnGlobalLayoutListener { scrollToEnd() }

private fun scrollToEnd() =
        (adapter.itemCount - 1).takeIf { it > 0 }?.let(recyclerView::smoothScrollToPosition)

How to get 'System.Web.Http, Version=5.2.3.0?

One way to fix it is by modifying the assembly redirect in the web.config file.

Modify the following:

<dependentAssembly>
        <assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.0.0.0" newVersion="4.0.0.0" />
</dependentAssembly>

to

<dependentAssembly>
        <assemblyIdentity name="System.Net.Http.Formatting" publicKeyToken="31bf3856ad364e35" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-5.2.3.0" newVersion="4.0.0.0" />
</dependentAssembly>

So the oldVersion attribute should change from "...-4.0.0.0" to "...-5.2.3.0".

What is the difference between XAMPP or WAMP Server & IIS?

WAMP [ Windows, Apache, Mysql, Php]

XAMPP [X-os, Apache, Mysql, Php , Perl ] (x-os : it can be used on any OS )

Both can be used to easily run and test websites and web applications locally. WAMP cannot be run parallel with XAMPP because with default installation XAMPP gets priority and it takes up ports.

WAMP easy to setup configuration in. WAMPServer has a graphical user interface to switch on or off individual component softwares while it is running. WAMPServer provide an option to switch among many versions of Apache, many versions of PHP and many versions of MySQL all installed which provide more flexibility towards developing while XAMPPServer doesn't have such an option. If you want to use Perl with WAMP you can configure Perl with WAMPServer http://phpflow.com/perl/how-to-configure-perl-on-wamp/ but it is better to go with XAMPP.

XAMPP is easy to use than WAMP. XAMPP is more powerful. XAMPP has a control panel from that you can start and stop individual components (such as MySQL,Apache etc.). XAMPP is more resource consuming than WAMP because of heavy amount of internal component softwares like Tomcat , FileZilla FTP server, Webalizer, Mercury Mail etc.So if you donot need high features better to go with WAMP. XAMPP also has SSL feature which WAMP doesn't.(Secure Sockets Layer (SSL) is a networking protocol that manages server authentication, client authentication and encrypted communication between servers and clients. )

IIS acronym for Internet Information Server also an extensible web server initiated as a research project for for Microsoft NT.IIS can be used for making Web applications, search engines, and Web-based applications that access databases such as SQL Server within Microsoft OSs. . IIS supports HTTP, HTTPS, FTP, FTPS, SMTP and NNTP.

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

I got this when building a project via Visual Studio Online (VSTS) Build using Visual Studio Build Steps.

The solution was:

  • Delete the existing source folder
  • Explicitly set 'Any CPU' in the platform for all Visual Studio Builds including dependencies (see screenshot below).
  • Re-run the build

VSO Screenshot

How can I populate a select dropdown list from a JSON feed with AngularJS?

<select name="selectedFacilityId" ng-model="selectedFacilityId">
         <option ng-repeat="facility in facilities" value="{{facility.id}}">{{facility.name}}</option>
     </select>  

This is an example on how to use it.

How to programmatically clear application data

Check this code to:

@Override
protected void onDestroy() {
// closing Entire Application
    android.os.Process.killProcess(android.os.Process.myPid());
    Editor editor = getSharedPreferences("clear_cache", Context.MODE_PRIVATE).edit();
    editor.clear();
    editor.commit();
    trimCache(this);
    super.onDestroy();
}


public static void trimCache(Context context) {
    try {
        File dir = context.getCacheDir();
        if (dir != null && dir.isDirectory()) {
            deleteDir(dir);

        }
    } catch (Exception e) {
        // TODO: handle exception
    }
}


public static boolean deleteDir(File dir) {
    if (dir != null && dir.isDirectory()) {
        String[] children = dir.list();
        for (int i = 0; i < children.length; i++) {
            boolean success = deleteDir(new File(dir, children[i]));
            if (!success) {
                return false;
            }
        }
    }

    // <uses-permission
    // android:name="android.permission.CLEAR_APP_CACHE"></uses-permission>
    // The directory is now empty so delete it

    return dir.delete();
}

call a function in success of datatable ajax call

The best way I have found is to use the initComplete method as it fires after the data has been retrieved and renders the table. NOTE this only fires once though.

$("#tableOfData").DataTable({
        "pageLength": 50,
        "ajax":{
            url: someurl,
            dataType : "json",
            type: "post",
            "data": {data to be sent}
        },
        "initComplete":function( settings, json){
            console.log(json);
            // call your function here
        }
    });

Static Initialization Blocks

It's also useful when you actually don't want to assign the value to anything, such as loading some class only once during runtime.

E.g.

static {
    try {
        Class.forName("com.example.jdbc.Driver");
    } catch (ClassNotFoundException e) {
        throw new ExceptionInInitializerError("Cannot load JDBC driver.", e);
    }
}

Hey, there's another benefit, you can use it to handle exceptions. Imagine that getStuff() here throws an Exception which really belongs in a catch block:

private static Object stuff = getStuff(); // Won't compile: unhandled exception.

then a static initializer is useful here. You can handle the exception there.

Another example is to do stuff afterwards which can't be done during assigning:

private static Properties config = new Properties();

static {
    try { 
        config.load(Thread.currentThread().getClassLoader().getResourceAsStream("config.properties");
    } catch (IOException e) {
        throw new ExceptionInInitializerError("Cannot load properties file.", e);
    }
}

To come back to the JDBC driver example, any decent JDBC driver itself also makes use of the static initializer to register itself in the DriverManager. Also see this and this answer.

Tomcat is not deploying my web project from Eclipse

Same problem, not sure why it occurred only after upgrading from Spring v3.2.x to v4.2.x.

Solved it by doing the following:

  1. Clear all eclipse files [.classpath, .project, .settings/].
  2. Perform >mvn eclipse:eclipse
  3. Perform eclipse>project>properties>deployment assembly add [referenced projects, additional classpaths].

Publish and Start the module in Tomcat tab, it now starts properly.

How to prevent a dialog from closing when a button is clicked

Inspired by Tom's answer, I believe the idea here is:

  • Set the onClickListener during the creation of the dialog to null
  • Then set a onClickListener after the dialog is shown.

You can override the onShowListener like Tom. Alternatively, you can

  1. get the button after calling AlertDialog's show()
  2. set the buttons' onClickListener as follows (slightly more readable I think).

Code:

AlertDialog.Builder builder = new AlertDialog.Builder(context);
// ...
final AlertDialog dialog = builder.create();
dialog.show();
// now you can override the default onClickListener
Button b = dialog.getButton(AlertDialog.BUTTON_POSITIVE);
b.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        Log.i(TAG, "ok button is clicked");
        handleClick(dialog);
    }
});

Left Outer Join using + sign in Oracle 11g

TableA LEFT OUTER JOIN TableB is equivalent to TableB RIGHT OUTER JOIN Table A.

In Oracle, (+) denotes the "optional" table in the JOIN. So in your first query, it's a P LEFT OUTER JOIN S. In your second query, it's S RIGHT OUTER JOIN P. They're functionally equivalent.

In the terminology, RIGHT or LEFT specify which side of the join always has a record, and the other side might be null. So in a P LEFT OUTER JOIN S, P will always have a record because it's on the LEFT, but S could be null.

See this example from java2s.com for additional explanation.


To clarify, I guess I'm saying that terminology doesn't matter, as it's only there to help visualize. What matters is that you understand the concept of how it works.


RIGHT vs LEFT

I've seen some confusion about what matters in determining RIGHT vs LEFT in implicit join syntax.

LEFT OUTER JOIN

SELECT *
FROM A, B
WHERE A.column = B.column(+)

RIGHT OUTER JOIN

SELECT *
FROM A, B
WHERE B.column(+) = A.column

All I did is swap sides of the terms in the WHERE clause, but they're still functionally equivalent. (See higher up in my answer for more info about that.) The placement of the (+) determines RIGHT or LEFT. (Specifically, if the (+) is on the right, it's a LEFT JOIN. If (+) is on the left, it's a RIGHT JOIN.)


Types of JOIN

The two styles of JOIN are implicit JOINs and explicit JOINs. They are different styles of writing JOINs, but they are functionally equivalent.

See this SO question.

Implicit JOINs simply list all tables together. The join conditions are specified in a WHERE clause.

Implicit JOIN

SELECT *
FROM A, B
WHERE A.column = B.column(+)

Explicit JOINs associate join conditions with a specific table's inclusion instead of in a WHERE clause.

Explicit JOIN

SELECT *
FROM A
LEFT OUTER JOIN B ON A.column = B.column

These Implicit JOINs can be more difficult to read and comprehend, and they also have a few limitations since the join conditions are mixed in other WHERE conditions. As such, implicit JOINs are generally recommended against in favor of explicit syntax.

How do I reference a local image in React?

The best way is to import the image first and then use it.

import React, { Component } from 'react';
import logo from '../logo.svg';
export default class Header extends Component {
  render() {
    return (
      <div className="row">
        <div className="logo">
          <img src={logo} width="100" height="50" />
        </div>
      </div>
    );
  }
} 

Postgresql - select something where date = "01/01/11"

I think you want to cast your dt to a date and fix the format of your date literal:

SELECT *
FROM table
WHERE dt::date = '2011-01-01' -- This should be ISO-8601 format, YYYY-MM-DD

Or the standard version:

SELECT *
FROM table
WHERE CAST(dt AS DATE) = '2011-01-01' -- This should be ISO-8601 format, YYYY-MM-DD

The extract function doesn't understand "date" and it returns a number.

Yes/No message box using QMessageBox

QT can be as simple as that of Windows. The equivalent code is

if (QMessageBox::Yes == QMessageBox(QMessageBox::Information, "title", "Question", QMessageBox::Yes|QMessageBox::No).exec()) 
{

}

Pure JavaScript Send POST Data Without a Form

Did you know that JavaScript has it's built-in methods and libs to create forms and submit them?

I am seeing a lot of replies here all asking to use a 3rd party library which I think is an overkill.

I would do the following in pure Javascript:

<script>
function launchMyForm()
{
   var myForm = document.createElement("FORM");
   myForm.setAttribute("id","TestForm");
   document.body.appendChild(myForm);

// this will create a new FORM which is mapped to the Java Object of myForm, with an id of TestForm. Equivalent to: <form id="TestForm"></form>

   var myInput = document.createElement("INPUT");
   myInput.setAttribute("id","MyInput");
   myInput.setAttribute("type","text");
   myInput.setAttribute("value","Heider");
   document.getElementById("TestForm").appendChild(myInput);

// This will create an INPUT equivalent to: <INPUT id="MyInput" type="text" value="Heider" /> and then assign it to be inside the TestForm tags. 
}
</script>

This way (A) you don't need to rely on 3rd parties to do the job. (B) It's all built-in to all browsers, (C) faster, (D) it works, feel free to try it out.

I hope this helps. H

How to find the path of the local git repository when I am possibly in a subdirectory

git rev-parse --show-toplevel

could be enough if executed within a git repo.
From git rev-parse man page:

--show-toplevel

Show the absolute path of the top-level directory.

For older versions (before 1.7.x), the other options are listed in "Is there a way to get the git root directory in one command?":

git rev-parse --git-dir

That would give the path of the .git directory.


The OP mentions:

git rev-parse --show-prefix

which returns the local path under the git repo root. (empty if you are at the git repo root)


Note: for simply checking if one is in a git repo, I find the following command quite expressive:

git rev-parse --is-inside-work-tree

And yes, if you need to check if you are in a .git git-dir folder:

git rev-parse --is-inside-git-dir

Object of class mysqli_result could not be converted to string in

Try with:

$row = mysqli_fetch_assoc($result);
echo "my result <a href='data/" . htmlentities($row['classtype'], ENT_QUOTES, 'UTF-8') . ".php'>My account</a>";

Switch with if, else if, else, and loops inside case

Seems like kind of a homely way of doing things, but if you must... you could restructure it as such to fit your needs:

boolean found = false;

case 1:

for (Element arrayItem : array) {
    if (arrayItem == whateverValue) {
        found = true;    
    } // else if ...
}
if (found) {
    break;
}
case 2:

How to detect the device orientation using CSS media queries?

I think we need to write more specific media query. Make sure if you write one media query it should be not effect to other view (Mob,Tab,Desk) otherwise it can be trouble. I would like suggest to write one basic media query for respective device which cover both view and one orientation media query that you can specific code more about orientation view its for good practice. we Don't need to write both media orientation query at same time. You can refer My below example. I am sorry if my English writing is not much good. Ex:

For Mobile

@media screen and (max-width:767px) {

..This is basic media query for respective device.In to this media query  CSS code cover the both view landscape and portrait view.

}


@media screen and (min-width:320px) and (max-width:767px) and (orientation:landscape) {


..This orientation media query. In to this orientation media query you can specify more about CSS code for landscape view.

}

For Tablet

@media screen and (max-width:1024px){
..This is basic media query for respective device.In to this media query  CSS code cover the both view landscape and portrait view.
}
@media screen and (min-width:768px) and (max-width:1024px) and (orientation:landscape){

..This orientation media query. In to this orientation media query you can specify more about CSS code for landscape view.

}

Desktop

make as per your design requirement enjoy...(:

Thanks, Jitu

Readably print out a python dict() sorted by key

Another short oneliner:

mydict = {'c': 1, 'b': 2, 'a': 3}
print(*sorted(mydict.items()), sep='\n')

TNS Protocol adapter error while starting Oracle SQL*Plus

Go to Start --> Run--> type " services.msc"

Select the OracleService name, Right Click, Start.

Wait for a while and then your service will start. Then go to your sql command line window and try to connect to your user. I hope you can do that now.

Redirect non-www to www in .htaccess

Try this, I used it in many websites, it works perfectly

Options +FollowSymLinks
RewriteEngine On
RewriteCond %{HTTP_HOST} ^bewebdeveloper.com$
RewriteRule ^(.*) http://www.bewebdeveloper.com/$1  [QSA,L,R=301]

Global variable Python classes

What you have is correct, though you will not call it global, it is a class attribute and can be accessed via class e.g Shape.lolwut or via an instance e.g. shape.lolwut but be careful while setting it as it will set an instance level attribute not class attribute

class Shape(object):
    lolwut = 1

shape = Shape()

print Shape.lolwut,  # 1
print shape.lolwut,  # 1

# setting shape.lolwut would not change class attribute lolwut 
# but will create it in the instance
shape.lolwut = 2

print Shape.lolwut,  # 1
print shape.lolwut,  # 2

# to change class attribute access it via class
Shape.lolwut = 3

print Shape.lolwut,  # 3
print shape.lolwut   # 2 

output:

1 1 1 2 3 2

Somebody may expect output to be 1 1 2 2 3 3 but it would be incorrect

Statistics: combinations in Python

That's probably as fast as you can do it in pure python for reasonably large inputs:

def choose(n, k):
    if k == n: return 1
    if k > n: return 0
    d, q = max(k, n-k), min(k, n-k)
    num =  1
    for n in xrange(d+1, n+1): num *= n
    denom = 1
    for d in xrange(1, q+1): denom *= d
    return num / denom

How to create a css rule for all elements except one class?

The negation pseudo-class seems to be what you are looking for.

table:not(.dojoxGrid) {color:red;}

It's not supported by = IE8 though.

Linux command line howto accept pairing for bluetooth device without pin

For Ubuntu 14.04 and Android try:

hcitool scan #get hardware address
sudo bluetooth-agent PIN HARDWARE-ADDRESS

PIN dialog pops up on Android device. Enter same PIN.

Note: sudo apt-get install bluez-utils might be necessary.

Note2: If PIN dialog does not appear, try pairing from Android first (will fail because of wrong PIN). Then try again as described above.

Split / Explode a column of dictionaries into separate columns with pandas

Try this: The data returned from SQL has to converted into a Dict. or could it be "Pollutant Levels" is now Pollutants'

   StationID                   Pollutants
0       8809  {"a":"46","b":"3","c":"12"}
1       8810   {"a":"36","b":"5","c":"8"}
2       8811            {"b":"2","c":"7"}
3       8812                   {"c":"11"}
4       8813          {"a":"82","c":"15"}


df2["Pollutants"] = df2["Pollutants"].apply(lambda x : dict(eval(x)) )
df3 = df2["Pollutants"].apply(pd.Series )

    a    b   c
0   46    3  12
1   36    5   8
2  NaN    2   7
3  NaN  NaN  11
4   82  NaN  15


result = pd.concat([df, df3], axis=1).drop('Pollutants', axis=1)
result

   StationID    a    b   c
0       8809   46    3  12
1       8810   36    5   8
2       8811  NaN    2   7
3       8812  NaN  NaN  11
4       8813   82  NaN  15

AngularJs directive not updating another directive's scope

Just wondering why you are using 2 directives?

It seems like, in this case it would be more straightforward to have a controller as the parent - handle adding the data from your service to its $scope, and pass the model you need from there into your warrantyDirective.

Or for that matter, you could use 0 directives to achieve the same result. (ie. move all functionality out of the separate directives and into a single controller).

It doesn't look like you're doing any explicit DOM transformation here, so in this case, perhaps using 2 directives is overcomplicating things.

Alternatively, have a look at the Angular documentation for directives: http://docs.angularjs.org/guide/directive The very last example at the bottom of the page explains how to wire up dependent directives.

How to store arbitrary data for some HTML tags

I have found the metadata plugin to be an excellent solution to the problem of storing arbitrary data with the html tag in a way that makes it easy to retrieve and use with jQuery.

Important: The actual file you include is is only 5 kb and not 37 kb (which is the size of the complete download package)

Here is an example of it being used to store values I use when generating a google analytics tracking event (note: data.label and data.value happen to be optional params)

$(function () {
    $.each($(".ga-event"), function (index, value) {
        $(value).click(function () {
            var data = $(value).metadata();
            if (data.label && data.value) {
                _gaq.push(['_trackEvent', data.category, data.action, data.label, data.value]);
            } else if (data.label) {
                _gaq.push(['_trackEvent', data.category, data.action, data.label]);
            } else {
                _gaq.push(['_trackEvent', data.category, data.action]);
            }
        });
    });
});

<input class="ga-event {category:'button', action:'click', label:'test', value:99}" type="button" value="Test"/>

Erase the current printed console line

You can use VT100 escape codes. Most terminals, including xterm, are VT100 aware. For erasing a line, this is ^[[2K. In C this gives:

printf("%c[2K", 27);

How to define hash tables in Bash?

Bash 3 solution:

In reading some of the answers I put together a quick little function I would like to contribute back that might help others.

# Define a hash like this
MYHASH=("firstName:Milan"
        "lastName:Adamovsky")

# Function to get value by key
getHashKey()
 {
  declare -a hash=("${!1}")
  local key
  local lookup=$2

  for key in "${hash[@]}" ; do
   KEY=${key%%:*}
   VALUE=${key#*:}
   if [[ $KEY == $lookup ]]
   then
    echo $VALUE
   fi
  done
 }

# Function to get a list of all keys
getHashKeys()
 {
  declare -a hash=("${!1}")
  local KEY
  local VALUE
  local key
  local lookup=$2

  for key in "${hash[@]}" ; do
   KEY=${key%%:*}
   VALUE=${key#*:}
   keys+="${KEY} "
  done

  echo $keys
 }

# Here we want to get the value of 'lastName'
echo $(getHashKey MYHASH[@] "lastName")


# Here we want to get all keys
echo $(getHashKeys MYHASH[@])

How to mark a method as obsolete or deprecated?

With ObsoleteAttribute you can to show the deprecated method. Obsolete attribute has three constructor:

  1. [Obsolete]: is a no parameter constructor and is a default using this attribute.
  2. [Obsolete(string message)]: in this format you can get message of why this method is deprecated.
  3. [Obsolete(string message, bool error)]: in this format message is very explicit but error means, in compilation time, compiler must be showing error and cause to fail compiling or not.

enter image description here

Flushing footer to bottom of the page, twitter bootstrap

For Sticky Footer we use two DIV's in the HTML for basic sticky footer effect. Write like this:

HTML

<div class="container"></div>

<div class="footer"></div>

CSS

body,html {
    height:100%;
}
.container {
    min-height:100%;
}
.footer {
    height:40px;
    margin-top:-40px;
}

Regular expression to match any character being repeated more than 10 times

A slightly more generic powershell example. In powershell 7, the match is highlighted including the last space (can you highlight in stack?).

'a b c d e f ' | select-string '([a-f] ){6,}'

a b c d e f 

How can I build for release/distribution on the Xcode 4?

They've bundled all the target/build configuration/debugging options stuff into "schemes". The transition guide has a good explanation.

Escape quote in web.config connection string

Odeds answer is almost complete. Just one thing to add.

  1. Escape xml special chars like Emanuele Greco said.
  2. Put the password in single quotes like Oded said
  3. (this one is new) Escape single ticks with another single tick (ref)

having this password="'; this sould be a valid connection string:

connectionString='Server=dbsrv;User ID=myDbUser;Password='&quot;&amp;&amp;;'

presenting ViewController with NavigationViewController swift

I used an extension to UIViewController and a struct to make sure that my current view is presented from the favourites

1.Struct for a global Bool

struct PresentedFromFavourites {
static var comingFromFav = false}

2.UIVeiwController extension: presented modally as in the second option by "stefandouganhyde - Option 2 " and solving the back

extension UIViewController {
func returnToFavourites()
{
    // you return to the storyboard wanted by changing the name
    let storyBoard : UIStoryboard = UIStoryboard(name: "Main", bundle:nil)
    let mainNavigationController = storyBoard.instantiateViewController(withIdentifier: "HomeNav") as! UINavigationController
    // Set animated to false
    let favViewController = storyBoard.instantiateViewController(withIdentifier: "Favourites")
    self.present(mainNavigationController, animated: false, completion: {
        mainNavigationController.pushViewController(favViewController, animated: false)
    })

}
// call this function in viewDidLoad()
// 
func addBackToFavouritesButton()
{
    if PresentedFromFavourites.comingFromFav
    {
        //Create a button
        // I found this good for most size classes
        let buttonHeight = (self.navigationController?.navigationBar.frame.size.height)! - 15
        let rect = CGRect(x: 2, y: 8, width: buttonHeight, height: buttonHeight)
        let aButton = UIButton(frame: rect)
        // Down a back arrow image from icon8 for free and add it to your image assets  
        aButton.setImage(#imageLiteral(resourceName: "backArrow"), for: .normal)
        aButton.backgroundColor = UIColor.clear
        aButton.addTarget(self, action:#selector(self.returnToFavourites), for: .touchUpInside)
        self.navigationController?.navigationBar.addSubview(aButton)
        PresentedFromFavourites.comingFromFav = false
    }

}}

How to get the absolute coordinates of a view

You can get a View's coordinates using getLocationOnScreen() or getLocationInWindow()

Afterwards, x and y should be the top-left corner of the view. If your root layout is smaller than the screen (like in a Dialog), using getLocationInWindow will be relative to its container, not the entire screen.

Java Solution

int[] point = new int[2];
view.getLocationOnScreen(point); // or getLocationInWindow(point)
int x = point[0];
int y = point[1];

NOTE: If value is always 0, you are likely changing the view immediately before requesting location.

To ensure view has had a chance to update, run your location request after the View's new layout has been calculated by using view.post:

view.post(() -> {
    // Values should no longer be 0
    int[] point = new int[2];
    view.getLocationOnScreen(point); // or getLocationInWindow(point)
    int x = point[0];
    int y = point[1];
});

~~

Kotlin Solution

val point = IntArray(2)
view.getLocationOnScreen(point) // or getLocationInWindow(point)
val (x, y) = point

NOTE: If value is always 0, you are likely changing the view immediately before requesting location.

To ensure view has had a chance to update, run your location request after the View's new layout has been calculated by using view.post:

view.post {
    // Values should no longer be 0
    val point = IntArray(2)
    view.getLocationOnScreen(point) // or getLocationInWindow(point)
    val (x, y) = point
}

I recommend creating an extension function for handling this:

// To use, call:
val (x, y) = view.screenLocation

val View.screenLocation get(): IntArray {
    val point = IntArray(2)
    getLocationOnScreen(point)
    return point
}

And if you require reliability, also add:

view.screenLocationSafe { x, y -> Log.d("", "Use $x and $y here") }

fun View.screenLocationSafe(callback: (Int, Int) -> Unit) {
    post {
        val (x, y) = screenLocation
        callback(x, y)
    }
}

How do I properly set the permgen size?

Completely removed from java 8 +
Partially removed from java 7 (interned Strings for example)
source

gcc error: wrong ELF class: ELFCLASS64

You can specify '-m32' or '-m64' to select the compilation mode.

When dealing with autoconf (configure) scripts, I usually set CC="gcc -m64" (or CC="gcc -m32") in the environment so that everything is compiled with the correct bittiness. At least, usually...people find endless ways to make that not quite work, but my batting average is very high (way over 95%) with it.

How to add/subtract time (hours, minutes, etc.) from a Pandas DataFrame.Index whos objects are of type datetime.time?

Liam's link looks great, but also check out pandas.Timedelta - looks like it plays nicely with NumPy's and Python's time deltas.

https://pandas.pydata.org/pandas-docs/stable/timedeltas.html

pd.date_range('2014-01-01', periods=10) + pd.Timedelta(days=1)

Javascript: 'window' is not defined

The window object represents an open window in a browser. Since you are not running your code within a browser, but via Windows Script Host, the interpreter won't be able to find the window object, since it does not exist, since you're not within a web browser.

How to run a hello.js file in Node.js on windows?

You need to make sure that node is in your PATH. To set up your path, this out.

Make sure that the directory that has node.exe is in your PATH. Then you should be able to run node path_to_js_file.js.

For a good "Hello World" example, check out: http://howtonode.org/hello-node

How to trigger click event on href element

Just want to let you guys know, the accepted answer doesn't always work.

Here's an example it will fail.

if <href='/list'>

href = $('css_selector').attr('href')
"/list"
href = document.querySelector('css_selector').href
"http://localhost/list"

or you could append the href you got from jQuery to this

href = document.URL +$('css_selector').attr('href');

or jQuery way

href = $('css_selector').prop('href')

Finally, invoke it to change the browser current page's url

window.location.href = href

or pop it out using window.open(url)

Here's an example in JSFiddle.

How to execute a shell script on a remote server using Ansible?

local_action runs the command on the local server, not on the servers you specify in hosts parameter.

Change your "Execute the script" task to

- name: Execute the script
  command: sh /home/test_user/test.sh

and it should do it.

You don't need to repeat sudo in the command line because you have defined it already in the playbook.

According to Ansible Intro to Playbooks user parameter was renamed to remote_user in Ansible 1.4 so you should change it, too

remote_user: test_user

So, the playbook will become:

---
- name: Transfer and execute a script.
  hosts: server
  remote_user: test_user
  sudo: yes
  tasks:
     - name: Transfer the script
       copy: src=test.sh dest=/home/test_user mode=0777

     - name: Execute the script
       command: sh /home/test_user/test.sh

List all liquibase sql types

I've found the liquibase.database.typeconversion.core.AbstractTypeConverter class. It lists all types that can be used:

protected DataType getDataType(String columnTypeString, Boolean autoIncrement, String dataTypeName, String precision, String additionalInformation) {
    // Translate type to database-specific type, if possible
    DataType returnTypeName = null;
    if (dataTypeName.equalsIgnoreCase("BIGINT")) {
        returnTypeName = getBigIntType();
    } else if (dataTypeName.equalsIgnoreCase("NUMBER") || dataTypeName.equalsIgnoreCase("NUMERIC")) {
        returnTypeName = getNumberType();
    } else if (dataTypeName.equalsIgnoreCase("BLOB")) {
        returnTypeName = getBlobType();
    } else if (dataTypeName.equalsIgnoreCase("BOOLEAN")) {
        returnTypeName = getBooleanType();
    } else if (dataTypeName.equalsIgnoreCase("CHAR")) {
        returnTypeName = getCharType();
    } else if (dataTypeName.equalsIgnoreCase("CLOB")) {
        returnTypeName = getClobType();
    } else if (dataTypeName.equalsIgnoreCase("CURRENCY")) {
        returnTypeName = getCurrencyType();
    } else if (dataTypeName.equalsIgnoreCase("DATE") || dataTypeName.equalsIgnoreCase(getDateType().getDataTypeName())) {
        returnTypeName = getDateType();
    } else if (dataTypeName.equalsIgnoreCase("DATETIME") || dataTypeName.equalsIgnoreCase(getDateTimeType().getDataTypeName())) {
        returnTypeName = getDateTimeType();
    } else if (dataTypeName.equalsIgnoreCase("DOUBLE")) {
        returnTypeName = getDoubleType();
    } else if (dataTypeName.equalsIgnoreCase("FLOAT")) {
        returnTypeName = getFloatType();
    } else if (dataTypeName.equalsIgnoreCase("INT")) {
        returnTypeName = getIntType();
    } else if (dataTypeName.equalsIgnoreCase("INTEGER")) {
        returnTypeName = getIntType();
    } else if (dataTypeName.equalsIgnoreCase("LONGBLOB")) {
        returnTypeName = getLongBlobType();
    } else if (dataTypeName.equalsIgnoreCase("LONGVARBINARY")) {
        returnTypeName = getBlobType();
    } else if (dataTypeName.equalsIgnoreCase("LONGVARCHAR")) {
        returnTypeName = getClobType();
    } else if (dataTypeName.equalsIgnoreCase("SMALLINT")) {
        returnTypeName = getSmallIntType();
    } else if (dataTypeName.equalsIgnoreCase("TEXT")) {
        returnTypeName = getClobType();
    } else if (dataTypeName.equalsIgnoreCase("TIME") || dataTypeName.equalsIgnoreCase(getTimeType().getDataTypeName())) {
        returnTypeName = getTimeType();
    } else if (dataTypeName.toUpperCase().contains("TIMESTAMP")) {
        returnTypeName = getDateTimeType();
    } else if (dataTypeName.equalsIgnoreCase("TINYINT")) {
        returnTypeName = getTinyIntType();
    } else if (dataTypeName.equalsIgnoreCase("UUID")) {
        returnTypeName = getUUIDType();
    } else if (dataTypeName.equalsIgnoreCase("VARCHAR")) {
        returnTypeName = getVarcharType();
    } else if (dataTypeName.equalsIgnoreCase("NVARCHAR")) {
        returnTypeName = getNVarcharType();
    } else {
        return new CustomType(columnTypeString,0,2);
    }

Sending HTTP POST Request In Java

Sending a POST request is easy in vanilla Java. Starting with a URL, we need t convert it to a URLConnection using url.openConnection();. After that, we need to cast it to a HttpURLConnection, so we can access its setRequestMethod() method to set our method. We finally say that we are going to send data over the connection.

URL url = new URL("https://www.example.com/login");
URLConnection con = url.openConnection();
HttpURLConnection http = (HttpURLConnection)con;
http.setRequestMethod("POST"); // PUT is another valid option
http.setDoOutput(true);

We then need to state what we are going to send:

Sending a simple form

A normal POST coming from a http form has a well defined format. We need to convert our input to this format:

Map<String,String> arguments = new HashMap<>();
arguments.put("username", "root");
arguments.put("password", "sjh76HSn!"); // This is a fake password obviously
StringJoiner sj = new StringJoiner("&");
for(Map.Entry<String,String> entry : arguments.entrySet())
    sj.add(URLEncoder.encode(entry.getKey(), "UTF-8") + "=" 
         + URLEncoder.encode(entry.getValue(), "UTF-8"));
byte[] out = sj.toString().getBytes(StandardCharsets.UTF_8);
int length = out.length;

We can then attach our form contents to the http request with proper headers and send it.

http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
    os.write(out);
}
// Do something with http.getInputStream()

Sending JSON

We can also send json using java, this is also easy:

byte[] out = "{\"username\":\"root\",\"password\":\"password\"}" .getBytes(StandardCharsets.UTF_8);
int length = out.length;

http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
http.connect();
try(OutputStream os = http.getOutputStream()) {
    os.write(out);
}
// Do something with http.getInputStream()

Remember that different servers accept different content-types for json, see this question.


Sending files with java post

Sending files can be considered more challenging to handle as the format is more complex. We are also going to add support for sending the files as a string, since we don't want to buffer the file fully into the memory.

For this, we define some helper methods:

private void sendFile(OutputStream out, String name, InputStream in, String fileName) {
    String o = "Content-Disposition: form-data; name=\"" + URLEncoder.encode(name,"UTF-8") 
             + "\"; filename=\"" + URLEncoder.encode(filename,"UTF-8") + "\"\r\n\r\n";
    out.write(o.getBytes(StandardCharsets.UTF_8));
    byte[] buffer = new byte[2048];
    for (int n = 0; n >= 0; n = in.read(buffer))
        out.write(buffer, 0, n);
    out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}

private void sendField(OutputStream out, String name, String field) {
    String o = "Content-Disposition: form-data; name=\"" 
             + URLEncoder.encode(name,"UTF-8") + "\"\r\n\r\n";
    out.write(o.getBytes(StandardCharsets.UTF_8));
    out.write(URLEncoder.encode(field,"UTF-8").getBytes(StandardCharsets.UTF_8));
    out.write("\r\n".getBytes(StandardCharsets.UTF_8));
}

We can then use these methods to create a multipart post request as follows:

String boundary = UUID.randomUUID().toString();
byte[] boundaryBytes = 
           ("--" + boundary + "\r\n").getBytes(StandardCharsets.UTF_8);
byte[] finishBoundaryBytes = 
           ("--" + boundary + "--").getBytes(StandardCharsets.UTF_8);
http.setRequestProperty("Content-Type", 
           "multipart/form-data; charset=UTF-8; boundary=" + boundary);

// Enable streaming mode with default settings
http.setChunkedStreamingMode(0); 

// Send our fields:
try(OutputStream out = http.getOutputStream()) {
    // Send our header (thx Algoman)
    out.write(boundaryBytes);

    // Send our first field
    sendField(out, "username", "root");

    // Send a seperator
    out.write(boundaryBytes);

    // Send our second field
    sendField(out, "password", "toor");

    // Send another seperator
    out.write(boundaryBytes);

    // Send our file
    try(InputStream file = new FileInputStream("test.txt")) {
        sendFile(out, "identification", file, "text.txt");
    }

    // Finish the request
    out.write(finishBoundaryBytes);
}


// Do something with http.getInputStream()

Uri content://media/external/file doesn't exist for some devices

Most probably it has to do with caching on the device. Catching the exception and ignoring is not nice but my problem was fixed and it seems to work.

jQuery .ready in a dynamically inserted iframe

Basically what others have already posted but IMHO a bit cleaner:

$('<iframe/>', {
    src: 'https://example.com/',
    load: function() {
        alert("loaded")
    }
}).appendTo('body');

Why do I get java.lang.AbstractMethodError when trying to load a blob in the db?

It looks that even if the driver 10.2 is compatible with the JDBC3 it may not work with JRE6 as I've found here:

http://www.oracle.com/technology/tech/java/sqlj_jdbc/htdocs/jdbc_faq.html#02_03

Which JDBC drivers support which versions of Javasoft's JDK?

pre-8i OCI and THIN Drivers - JDK 1.0.x and JDK 1.1.x
8.1.5 OCI and THIN Drivers - JDK 1.0.x and JDK 1.1.x
8.1.6SDK THIN Driver - JDK 1.1.x and JDK 1.2.x (aka Java2)
8.1.6SDK OCI Driver - Only JDK 1.1.x
8.1.6 OCI and THIN Driver - JDK 1.1.x and JDK 1.2.x
8.1.7 OCI and THIN Driver - JDK 1.1.x and JDK 1.2.x
9.0.1 OCI and THIN Driver - JDK 1.1.x, JDK 1.2.x and JDK 1.3.x
9.2.0 OCI and THIN Driver - JDK 1.1.x, JDK 1.2.x, JDK 1.3.x, and JDK 1.4.x
10.1.0 OCI and THIN Driver - JDK 1.2.x, JDK 1.3.x, and JDK 1.4.x
10.2.0 OCI and THIN Driver - JDK 1.2.x, JDK 1.3.x, JDK 1.4.x, and JDK 5.0.x
11.1.0 OCI and THIN Driver - JDK 1.5.x and JDK 1.6.x

Oracle 10.2.0 supports:

Full support for JDBC 3.0
Note that there is no real change in the support for the following in the database. Allthat has changed is that some methods that previously threw SQLException now do something more reasonable instead.
result-set holdability
returning multiple result-sets.

refresh leaflet map: map container is already initialized

What you can try is to remove the map before initialising it or when you leave the page:

if(this.map) {
  this.map.remove();
}

Simple (I think) Horizontal Line in WPF?

To draw Horizontal 
************************    
<Rectangle  HorizontalAlignment="Stretch"  VerticalAlignment="Center" Fill="DarkCyan" Height="4"/>

To draw vertical 
*******************
 <Rectangle  HorizontalAlignment="Stretch" VerticalAlignment="Center" Fill="DarkCyan" Height="4" Width="Auto" >
        <Rectangle.RenderTransform>
            <TransformGroup>
                <ScaleTransform/>
                <SkewTransform/>
                <RotateTransform Angle="90"/>
                <TranslateTransform/>
            </TransformGroup>
        </Rectangle.RenderTransform>
    </Rectangle>

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

I had the same problem, and all the solutions from SO or Google didn't work for me. Usually, setNeedsDisplay does work, but when it doesn't...
I've tried calling setNeedsDisplay of the view just every possible way from every possible threads and stuff - still no success. We know, as Rob said, that

"this needs to be drawn in the next draw cycle."

But for some reason it wouldn't draw this time. And the only solution I've found is calling it manually after some time, to let anything that blocks the draw pass away, like this:

dispatch_time_t popTime = dispatch_time(DISPATCH_TIME_NOW, 
                                        (int64_t)(0.005 * NSEC_PER_SEC));
dispatch_after(popTime, dispatch_get_main_queue(), ^(void) {
    [viewToRefresh setNeedsDisplay];
});

It's a good solution if you don't need the view to redraw really often. Otherwise, if you're doing some moving (action) stuff, there is usually no problems with just calling setNeedsDisplay.

I hope it will help someone who is lost there, like I was.

How can I tell Moq to return a Task?

Now you can also use Talentsoft.Moq.SetupAsync package https://github.com/TalentSoft/Moq.SetupAsync

Which on the base on the answers found here and ideas proposed to Moq but still not yet implemented here: https://github.com/moq/moq4/issues/384, greatly simplify setup of async methods

Few examples found in previous responses done with SetupAsync extension:

mock.SetupAsync(arg=>arg.DoSomethingAsync());
mock.SetupAsync(arg=>arg.DoSomethingAsync()).Callback(() => { <my code here> });
mock.SetupAsync(arg=>arg.DoSomethingAsync()).Throws(new InvalidOperationException());

How can I erase all inline styles with javascript and leave only the styles specified in the css style sheet?

If you need to just empty the style of an element then:
element.style.cssText = null;
This should do good. Hope it helps!

ICommand MVVM implementation

I have written this article about the ICommand interface.

The idea - creating a universal command that takes two delegates: one is called when ICommand.Execute (object param) is invoked, the second checks the status of whether you can execute the command (ICommand.CanExecute (object param)).

Requires the method to switching event CanExecuteChanged. It is called from the user interface elements for switching the state CanExecute() command.

public class ModelCommand : ICommand
{
    #region Constructors

    public ModelCommand(Action<object> execute)
        : this(execute, null) { }

    public ModelCommand(Action<object> execute, Predicate<object> canExecute)
    {
        _execute = execute;
        _canExecute = canExecute;
    }

    #endregion

    #region ICommand Members

    public event EventHandler CanExecuteChanged;

    public bool CanExecute(object parameter)
    {
        return _canExecute != null ? _canExecute(parameter) : true;
    }

    public void Execute(object parameter)
    {
        if (_execute != null)
            _execute(parameter);
    }

    public void OnCanExecuteChanged()
    {
        CanExecuteChanged(this, EventArgs.Empty);
    }

    #endregion

    private readonly Action<object> _execute = null;
    private readonly Predicate<object> _canExecute = null;
}

Reload the page after ajax success

use this Reload page

success: function(data){
   if(data.success == true){ // if true (1)
      setTimeout(function(){// wait for 5 secs(2)
           location.reload(); // then reload the page.(3)
      }, 5000); 
   }
}

Nginx Different Domains on Same IP

Your "listen" directives are wrong. See this page: http://nginx.org/en/docs/http/server_names.html.

They should be

server {
    listen      80;
    server_name www.domain1.com;
    root /var/www/domain1;
}

server {
    listen       80;
    server_name www.domain2.com;
    root /var/www/domain2;
}

Note, I have only included the relevant lines. Everything else looked okay but I just deleted it for clarity. To test it you might want to try serving a text file from each server first before actually serving php. That's why I left the 'root' directive in there.

Node.js request CERT_HAS_EXPIRED

Here is a more concise way to achieve the "less insecure" method proposed by CoolAJ86

request({
  url: url,
  agentOptions: {
    rejectUnauthorized: false
  }
}, function (err, resp, body) {
  // ...
});

Paramiko's SSHClient with SFTP

paramiko.SFTPClient

Sample Usage:

import paramiko
paramiko.util.log_to_file("paramiko.log")

# Open a transport
host,port = "example.com",22
transport = paramiko.Transport((host,port))

# Auth    
username,password = "bar","foo"
transport.connect(None,username,password)

# Go!    
sftp = paramiko.SFTPClient.from_transport(transport)

# Download
filepath = "/etc/passwd"
localpath = "/home/remotepasswd"
sftp.get(filepath,localpath)

# Upload
filepath = "/home/foo.jpg"
localpath = "/home/pony.jpg"
sftp.put(localpath,filepath)

# Close
if sftp: sftp.close()
if transport: transport.close()

How to use orderby with 2 fields in linq?

If you have two or more field to order try this:

var soterdList = initialList.OrderBy(x => x.Priority).
                                    ThenBy(x => x.ArrivalDate).
                                    ThenBy(x => x.ShipDate);

You can add other fields with clasole "ThenBy"

Vertical Menu in Bootstrap

No, not in the current one. But you can take a look at the next version by downloading it from github. It has vertical pills and tabs. Maybe that will help? (be aware, it's under construction tho)

Spring: Returning empty HTTP Responses with ResponseEntity<Void> doesn't work

For Spring 5.2+ this works for me:

@PostMapping("/foo")
ResponseEntity<Void> foo(@PathVariable UUID fooId) {
    return fooService.findExam(fooId)
            .map(uri -> ResponseEntity.noContent().<Void>build())
            .orElse(ResponseEntity.notFound().build());
}

Apache server keeps crashing, "caught SIGTERM, shutting down"

try to disable the rewrite module in ubuntu using sudo a2dismod rewrite. This will perhaps stop your apache server to crash.

Cross origin requests are only supported for HTTP but it's not cross-domain

REM kill all existing instance of chrome 
taskkill /F /IM chrome.exe /T
REM directory path where chrome.exe is located
set chromeLocation="C:\Program Files (x86)\Google\Chrome\Application"
cd %chromeLocation%
cd c:
start chrome.exe --allow-file-access-from-files
  1. change chromeLocation path with yours.

  2. save above as .bat file.

  3. drag drop you file on the batch file you created. (chrome does give restore pages option though so if you have pages open just hit restore and it will work).

Remove the last character in a string in T-SQL?

I love @bill-hoenig 's answer; however, I was using a subquery and I got caught up because the REVERSE function needed two sets of parentheses. Took me a while to figure that one out!

SELECT
   -- Return comma delimited list of all payment reasons for this Visit
   REVERSE(STUFF(REVERSE((
        SELECT DISTINCT
               CAST(CONVERT(varchar, r1.CodeID) + ' - ' + c.Name + ', ' AS VARCHAR(MAX))
          FROM VisitReason r1
          LEFT JOIN ReasonCode c        ON c.ID = r1.ReasonCodeID
         WHERE p.ID = r1.PaymentID
         FOR XML PATH('')
              )), 1, 2, ''))                        ReasonCode
  FROM Payments p

How to scan a folder in Java?

Not sure how you want to represent the tree? Anyway here's an example which scans the entire subtree using recursion. Files and directories are treated alike. Note that File.listFiles() returns null for non-directories.

public static void main(String[] args) {
    Collection<File> all = new ArrayList<File>();
    addTree(new File("."), all);
    System.out.println(all);
}

static void addTree(File file, Collection<File> all) {
    File[] children = file.listFiles();
    if (children != null) {
        for (File child : children) {
            all.add(child);
            addTree(child, all);
        }
    }
}

Java 7 offers a couple of improvements. For example, DirectoryStream provides one result at a time - the caller no longer has to wait for all I/O operations to complete before acting. This allows incremental GUI updates, early cancellation, etc.

static void addTree(Path directory, Collection<Path> all)
        throws IOException {
    try (DirectoryStream<Path> ds = Files.newDirectoryStream(directory)) {
        for (Path child : ds) {
            all.add(child);
            if (Files.isDirectory(child)) {
                addTree(child, all);
            }
        }
    }
}

Note that the dreaded null return value has been replaced by IOException.

Java 7 also offers a tree walker:

static void addTree(Path directory, final Collection<Path> all)
        throws IOException {
    Files.walkFileTree(directory, new SimpleFileVisitor<Path>() {
        @Override
        public FileVisitResult visitFile(Path file, BasicFileAttributes attrs)
                throws IOException {
            all.add(file);
            return FileVisitResult.CONTINUE;
        }
    });
}

Register .NET Framework 4.5 in IIS 7.5

For Windows 8 and Windows Server 2012 use dism /online /enable-feature /featurename:IIS-ASPNET45 As administrative command prompt.

Different color for each bar in a bar chart; ChartJS

You can generate easily with livegap charts
Select Mulicolors from Bar menu


(source: livegap.com)

** chart library used is chartnew.js modified version of chart.js library
with chartnew.js code will be something like this

var barChartData = {
        labels: ["001", "002", "003", "004", "005", "006", "007"],
        datasets: [
            {
                label: "My First dataset",
                fillColor: ["rgba(0,10,220,0.5)","rgba(220,0,10,0.5)","rgba(220,0,0,0.5)","rgba(120,250,120,0.5)" ],
                strokeColor: "rgba(220,220,220,0.8)", 
                highlightFill: "rgba(220,220,220,0.75)",
                highlightStroke: "rgba(220,220,220,1)",
                data: [20, 59, 80, 81, 56, 55, 40]
            }
        ]
    };

.NET NewtonSoft JSON deserialize map to a different property name

Adding to Jacks solution. I need to Deserialize using the JsonProperty and Serialize while ignoring the JsonProperty (or vice versa). ReflectionHelper and Attribute Helper are just helper classes that get a list of properties or attributes for a property. I can include if anyone actually cares. Using the example below you can serialize the viewmodel and get "Amount" even though the JsonProperty is "RecurringPrice".

    /// <summary>
    /// Ignore the Json Property attribute. This is usefule when you want to serialize or deserialize differently and not 
    /// let the JsonProperty control everything.
    /// </summary>
    /// <typeparam name="T"></typeparam>
    public class IgnoreJsonPropertyResolver<T> : DefaultContractResolver
    {
        private Dictionary<string, string> PropertyMappings { get; set; }

        public IgnoreJsonPropertyResolver()
        {
            this.PropertyMappings = new Dictionary<string, string>();
            var properties = ReflectionHelper<T>.GetGetProperties(false)();
            foreach (var propertyInfo in properties)
            {
                var jsonProperty = AttributeHelper.GetAttribute<JsonPropertyAttribute>(propertyInfo);
                if (jsonProperty != null)
                {
                    PropertyMappings.Add(jsonProperty.PropertyName, propertyInfo.Name);
                }
            }
        }

        protected override string ResolvePropertyName(string propertyName)
        {
            string resolvedName = null;
            var resolved = this.PropertyMappings.TryGetValue(propertyName, out resolvedName);
            return (resolved) ? resolvedName : base.ResolvePropertyName(propertyName);
        }
    }

Usage:

        var settings = new JsonSerializerSettings();
        settings.DateFormatString = "YYYY-MM-DD";
        settings.ContractResolver = new IgnoreJsonPropertyResolver<PlanViewModel>();
        var model = new PlanViewModel() {Amount = 100};
        var strModel = JsonConvert.SerializeObject(model,settings);

Model:

public class PlanViewModel
{

    /// <summary>
    ///     The customer is charged an amount over an interval for the subscription.
    /// </summary>
    [JsonProperty(PropertyName = "RecurringPrice")]
    public double Amount { get; set; }

    /// <summary>
    ///     Indicates the number of intervals between each billing. If interval=2, the customer would be billed every two
    ///     months or years depending on the value for interval_unit.
    /// </summary>
    public int Interval { get; set; } = 1;

    /// <summary>
    ///     Number of free trial days that can be granted when a customer is subscribed to this plan.
    /// </summary>
    public int TrialPeriod { get; set; } = 30;

    /// <summary>
    /// This indicates a one-time fee charged upfront while creating a subscription for this plan.
    /// </summary>
    [JsonProperty(PropertyName = "SetupFee")]
    public double SetupAmount { get; set; } = 0;


    /// <summary>
    /// String representing the type id, usually a lookup value, for the record.
    /// </summary>
    [JsonProperty(PropertyName = "TypeId")]
    public string Type { get; set; }

    /// <summary>
    /// Billing Frequency
    /// </summary>
    [JsonProperty(PropertyName = "BillingFrequency")]
    public string Period { get; set; }


    /// <summary>
    /// String representing the type id, usually a lookup value, for the record.
    /// </summary>
    [JsonProperty(PropertyName = "PlanUseType")]
    public string Purpose { get; set; }
}

Fatal error: Call to undefined function: ldap_connect()

If you are a Windows user, this is a common error when you use XAMPP since LDAP is not enabled by default.

You can follow this steps to make sure LDAP works in your XAMPP:

  • [Your Drive]:\xampp\php\php.ini: In this file uncomment the following line:

     extension=php_ldap.dll
    
  • Move the file: libsasl.dll, from [Your Drive]:\xampp\php to [Your Drive]:\xampp\apache\bin (Note: moving the file is needed only for XAMPP prior to version: 5.6.28)

  • Restart Apache.

  • You can now use functions of the LDAP Module!

If you use Linux:

For php5:

sudo apt-get install php5-ldap

For php7:

sudo apt-get install php7.0-ldap

If you are using the latest version of PHP you can do

sudo apt-get install php-ldap

running the above command should do the trick.

if for any reason it doesn't work check your php.ini configuration to enable ldap, remove the semicolon before extension=ldap to uncomment, save and restart Apache

Why can't non-default arguments follow default arguments?

Required arguments (the ones without defaults), must be at the start to allow client code to only supply two. If the optional arguments were at the start, it would be confusing:

fun1("who is who", 3, "jack")

What would that do in your first example? In the last, x is "who is who", y is 3 and a = "jack".

How to upload and parse a CSV file in php

function doParseCSVFile($filesArray)
    {
        if ((file_exists($filesArray['frmUpload']['name'])) && (is_readable($filesArray['frmUpload']['name']))) { 

            $strFilePath = $filesArray['frmUpload']['tmp_name']; 

            $strFileHandle = fopen($strFilePath,"r");
            $line_of_text = fgetcsv($strFileHandle,1024,",","'"); 
            $line_of_text = fgetcsv($strFileHandle,1024,",","'"); 

            do { 
                if ($line_of_text[0]) { 
                    $strInsertSql = "INSERT INTO tbl_employee(employee_name, employee_code, employee_email, employee_designation, employee_number)VALUES('".addslashes($line_of_text[0])."', '".$line_of_text[1]."', '".addslashes($line_of_text[2])."', '".$line_of_text[3]."', '".$line_of_text[4]."')";
                    ExecuteQry($strInsertSql);
                }               
            } while (($line_of_text = fgetcsv($strFileHandle,1024,",","'"))!== FALSE);

        } else {
            return FALSE;
        }
    }

Can a java file have more than one class?

Yes You can have more than one Class in one .Java file . But You have make one of them Public . and save .java file with same name as name of public class. when you will compile that .java file than you will get Separate .class files for each class defined in .java file .

Apart from this there are too many method for defining more than one class in one .java file .

  1. use concept of Inner Classes.
  2. Use Concept of Anonymous Classes .

Windows equivalent of $export

There is not an equivalent statement for export in Windows Command Prompt. In Windows the environment is copied so when you exit from the session (from a called command prompt or from an executable that set a variable) the variable in Windows get lost. You can set it in user registry or in machine registry via setx but you won't see it if you not start a new command prompt.

Hide div if screen is smaller than a certain width

Is your logic not round the wrong way in that example, you have it hiding when the screen is bigger than 1024. Reverse the cases, make the none in to a block and vice versa.

No module named setuptools

For Python Run This Command

apt-get install -y python-setuptools

For Python 3.

apt-get install -y python3-setuptools

Use JavaScript to place cursor at end of text in text input element

I wanted to put cursor at the end of a "div" element where contenteditable = true, and I got a solution with Xeoncross code:

<input type="button" value="Paste HTML" onclick="document.getElementById('test').focus(); pasteHtmlAtCaret('<b>INSERTED</b>'); ">

<div id="test" contenteditable="true">
    Here is some nice text
</div>

And this function do magic:

 function pasteHtmlAtCaret(html) {
    var sel, range;
    if (window.getSelection) {
        // IE9 and non-IE
        sel = window.getSelection();
        if (sel.getRangeAt && sel.rangeCount) {
            range = sel.getRangeAt(0);
            range.deleteContents();

            // Range.createContextualFragment() would be useful here but is
            // non-standard and not supported in all browsers (IE9, for one)
            var el = document.createElement("div");
            el.innerHTML = html;
            var frag = document.createDocumentFragment(), node, lastNode;
            while ( (node = el.firstChild) ) {
                lastNode = frag.appendChild(node);
            }
            range.insertNode(frag);

            // Preserve the selection
            if (lastNode) {
                range = range.cloneRange();
                range.setStartAfter(lastNode);
                range.collapse(true);
                sel.removeAllRanges();
                sel.addRange(range);
            }
        }
    } else if (document.selection && document.selection.type != "Control") {
        // IE < 9
        document.selection.createRange().pasteHTML(html);
    }
}

Works fine for most browsers, please check it, this code puts text and put focus at the end of the text in div element (not input element)

https://jsfiddle.net/Xeoncross/4tUDk/

Thanks, Xeoncross

GetType used in PowerShell, difference between variables

Select-Object creates a new psobject and copies the properties you requested to it. You can verify this with GetType():

PS > $a.GetType().fullname
System.DayOfWeek

PS > $b.GetType().fullname
System.Management.Automation.PSCustomObject

How to disable CSS in Browser for testing purposes

Expanding on scrappedocola/renergy's idea, you can turn the JavaScript into a bookmarklet that executes against the javascript: uri so the code can be re-used easily across multiple pages without having to open up the dev tools or keep anything on your clipboard.

Just run the following snippet and drag the link to your bookmarks/favorites bar:

_x000D_
_x000D_
<a href="javascript: var el = document.querySelectorAll('style,link');_x000D_
         for (var i=0; i<el.length; i++) {_x000D_
           el[i].parentNode.removeChild(el[i]); _x000D_
         };">_x000D_
  Remove Styles _x000D_
</a>
_x000D_
_x000D_
_x000D_

  • I would avoid looping through the thousands of elements on a page with getElementsByTagName('*') and have to check and act on each individually.
  • I would avoid relying on jQuery existing on the page with $('style,link[rel="stylesheet"]').remove() when the extra javascript is not overwhelmingly cumbersome.

If statement within Where clause

CASE might help you out:

SELECT t.first_name,
       t.last_name,
       t.employid,
       t.status
  FROM employeetable t
 WHERE t.status = (CASE WHEN status_flag = STATUS_ACTIVE THEN 'A'
                        WHEN status_flag = STATUS_INACTIVE THEN 'T'
                        ELSE null END)
   AND t.business_unit = (CASE WHEN source_flag = SOURCE_FUNCTION THEN 'production'
                               WHEN source_flag = SOURCE_USER THEN 'users'
                               ELSE null END)
   AND t.first_name LIKE firstname
   AND t.last_name LIKE lastname
   AND t.employid LIKE employeeid;

The CASE statement evaluates multiple conditions to produce a single value. So, in the first usage, I check the value of status_flag, returning 'A', 'T' or null depending on what it's value is, and compare that to t.status. I do the same for the business_unit column with a second CASE statement.

Command to get latest Git commit hash from a branch

Note that when using "git log -n 1 [branch_name]" option. -n returns only one line of log but order in which this is returned is not guaranteed. Following is extract from git-log man page

.....
.....
Commit Limiting

Besides specifying a range of commits that should be listed using the special notations explained in the     description, additional commit limiting may be applied.

Using more options generally further limits the output (e.g. --since=<date1> limits to commits newer than <date1>, and using it with --grep=<pattern> further limits to commits whose log message has a line that matches <pattern>), unless otherwise noted.

Note that these are applied before commit ordering and formatting options, such as --reverse.

-<number>
-n <number>
.....
.....

Getting a slice of keys from a map

I made a sketchy benchmark on the three methods described in other responses.

Obviously pre-allocating the slice before pulling the keys is faster than appending, but surprisingly, the reflect.ValueOf(m).MapKeys() method is significantly slower than the latter:

? go run scratch.go
populating
filling 100000000 slots
done in 56.630774791s
running prealloc
took: 9.989049786s
running append
took: 18.948676741s
running reflect
took: 25.50070649s

Here's the code: https://play.golang.org/p/Z8O6a2jyfTH (running it in the playground aborts claiming that it takes too long, so, well, run it locally.)

Add x and y labels to a pandas plot

pandas uses matplotlib for basic dataframe plots. So, if you are using pandas for basic plot you can use matplotlib for plot customization. However, I propose an alternative method here using seaborn which allows more customization of the plot while not going into the basic level of matplotlib.

Working Code:

import pandas as pd
import seaborn as sns
values = [[1, 2], [2, 5]]
df2 = pd.DataFrame(values, columns=['Type A', 'Type B'], 
                   index=['Index 1', 'Index 2'])
ax= sns.lineplot(data=df2, markers= True)
ax.set(xlabel='xlabel', ylabel='ylabel', title='Video streaming dropout by category') 

enter image description here

How to set array length in c# dynamically

Use Array.CreateInstance to create an array dynamically.

    private Update BuildMetaData(MetaData[] nvPairs)
    {
        Update update = new Update();
        InputProperty[] ip = Array.CreateInstance(typeof(InputProperty), nvPairs.Count()) as InputProperty[];
        int i;
        for (i = 0; i < nvPairs.Length; i++)
        {
            if (nvPairs[i] == null) break;
            ip[i] = new InputProperty();
            ip[i].Name = "udf:" + nvPairs[i].Name;
            ip[i].Val = nvPairs[i].Value;
        }
        update.Items = ip;
        return update;
    }

What does "res.render" do, and what does the html file look like?

Renders a view and sends the rendered HTML string to the client.

res.render('index');

Or

res.render('index', function(err, html) {
  if(err) {...}
  res.send(html);
});

DOCS HERE: https://expressjs.com/en/api.html#res.render

Change value of variable with dplyr

We can use replace to change the values in 'mpg' to NA that corresponds to cyl==4.

mtcars %>%
     mutate(mpg=replace(mpg, cyl==4, NA)) %>%
     as.data.frame()

Convert StreamReader to byte[]

You can also use CopyTo:

var ms = new MemoryStream();
yourStreamReader.BaseStream.CopyTo(ms); // blocking call till the end of the stream
ms.GetBuffer().CopyTo(yourArray, ms.Length);

or

var ms = new MemoryStream();
var ct = yourStreamReader.BaseStream.CopyToAsync(ms);
await ct;
ms.GetBuffer().CopyTo(yourArray, ms.Length);

Intellij IDEA Java classes not auto compiling on save

I ended up recording a Macro to save and compile in one step, and keymap Ctrl+s to it.

How do you push just a single Git branch (and no other branches)?

By default git push updates all the remote branches. But you can configure git to update only the current branch to it's upstream.

git config push.default upstream

It means git will update only the current (checked out) branch when you do git push.

Other valid options are:

  • nothing : Do not push anything (error out) unless a refspec is explicitly given. This is primarily meant for people who want to avoid mistakes by always being explicit.
  • matching : Push all branches having the same name on both ends. (default option prior to Ver 1.7.11)
  • upstream: Push the current branch to its upstream branch. This mode only makes sense if you are pushing to the same repository you would normally pull from (i.e. central workflow). No need to have the same name for local and remote branch.
  • tracking : Deprecated, use upstream instead.
  • current : Push the current branch to the remote branch of the same name on the receiving end. Works in both central and non-central workflows.
  • simple : [available since Ver 1.7.11] in centralized workflow, work like upstream with an added safety to refuse to push if the upstream branch’s name is different from the local one. When pushing to a remote that is different from the remote you normally pull from, work as current. This is the safest option and is suited for beginners. This mode has become the default in Git 2.0.

Data binding to SelectedItem in a WPF Treeview

(Let's just all agree that TreeView is obviously busted in respect to this problem. Binding to SelectedItem would have been obvious. Sigh)

I needed the solution to interact properly with the IsSelected property of TreeViewItem, so here's how I did it:

// the Type CustomThing needs to implement IsSelected with notification
// for this to work.
public class CustomTreeView : TreeView
{
    public CustomThing SelectedCustomThing
    {
        get
        {
            return (CustomThing)GetValue(SelectedNode_Property);
        }
        set
        {
            SetValue(SelectedNode_Property, value);
            if(value != null) value.IsSelected = true;
        }
    }

    public static DependencyProperty SelectedNode_Property =
        DependencyProperty.Register(
            "SelectedCustomThing",
            typeof(CustomThing),
            typeof(CustomTreeView),
            new FrameworkPropertyMetadata(
                null,
                FrameworkPropertyMetadataOptions.None,
                SelectedNodeChanged));

    public CustomTreeView(): base()
    {
        this.SelectedItemChanged += new RoutedPropertyChangedEventHandler<object>(SelectedItemChanged_CustomHandler);
    }

    void SelectedItemChanged_CustomHandler(object sender, RoutedPropertyChangedEventArgs<object> e)
    {
        SetValue(SelectedNode_Property, SelectedItem);
    }

    private static void SelectedNodeChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var treeView = d as CustomTreeView;
        var newNode = e.NewValue as CustomThing;

        treeView.SelectedCustomThing = (CustomThing)e.NewValue;
    }
}

With this XAML:

<local:CustonTreeView ItemsSource="{Binding TreeRoot}" 
    SelectedCustomThing="{Binding SelectedNode,Mode=TwoWay}">
    <TreeView.ItemContainerStyle>
        <Style TargetType="TreeViewItem">
            <Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
        </Style>
    </TreeView.ItemContainerStyle>
</local:CustonTreeView>

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

You should be using datetime.datetime.strptime. Note that very old versions of Python (2.4 and older) don't have datetime.datetime.strptime; use time.strptime in that case.

How to Enable ActiveX in Chrome?

http://wiki.answers.com/Q/Does_Google_Chrome_support_ActiveX

Google Chrome comes with an ActiveX shim, as part of its default plugin array. So Google Chrome features at least partial support for ActiveX controls (as do many non-Internet Explorer browsers). I can't find information as to whether or not this includes support for ActiveX security certificates or the like, nor if/where such plugins can be controlled, within the browser.

..... Note that to enable the plug-in you must run Chrome with the following switch " --allow-all-activex" So in shortcut that is used to start up Chrome, add this after "Chrome.exe"

Bootstrap: add margin/padding space between columns

You may use the padding and margin shorthand Bootstrap 4 classes as follows:

For extra small devices i.e. xs

{property}{sides}-{size}

For other devices/viewports (small, medium, large and extra large)

{property}{sides}-{breakpoint}-{size}

Where:

property = m for margin and p for padding

Following are sides shorthand meanings:

l = defines the left-margin or left-padding
r = defines the right-margin or right-padding
t = defines the top-margin or top-padding
b = defines the bottom-margin or right-padding
x = For setting left and right padding and margins by the single call
y = For setting top and bottom margins
blank = margin and padding for all sides

The breakpoint = sm, md, lg, and xl.

Combining all the above, the left padding complete code can be (for example):

For left padding in extra small devices

pl-2

or for medium to extra large

pl-md-2

What are the differences between stateless and stateful systems, and how do they impact parallelism?

A stateful server keeps state between connections. A stateless server does not.

So, when you send a request to a stateful server, it may create some kind of connection object that tracks what information you request. When you send another request, that request operates on the state from the previous request. So you can send a request to "open" something. And then you can send a request to "close" it later. In-between the two requests, that thing is "open" on the server.

When you send a request to a stateless server, it does not create any objects that track information regarding your requests. If you "open" something on the server, the server retains no information at all that you have something open. A "close" operation would make no sense, since there would be nothing to close.

HTTP and NFS are stateless protocols. Each request stands on its own.

Sometimes cookies are used to add some state to a stateless protocol. In HTTP (web pages), the server sends you a cookie and then the browser holds the state, only to send it back to the server on a subsequent request.

SMB is a stateful protocol. A client can open a file on the server, and the server may deny other clients access to that file until the client closes it.

Java Serializable Object to Byte Array

Prepare the byte array to send:

ByteArrayOutputStream bos = new ByteArrayOutputStream();
ObjectOutputStream out = null;
try {
  out = new ObjectOutputStream(bos);   
  out.writeObject(yourObject);
  out.flush();
  byte[] yourBytes = bos.toByteArray();
  ...
} finally {
  try {
    bos.close();
  } catch (IOException ex) {
    // ignore close exception
  }
}

Create an object from a byte array:

ByteArrayInputStream bis = new ByteArrayInputStream(yourBytes);
ObjectInput in = null;
try {
  in = new ObjectInputStream(bis);
  Object o = in.readObject(); 
  ...
} finally {
  try {
    if (in != null) {
      in.close();
    }
  } catch (IOException ex) {
    // ignore close exception
  }
}

Static link of shared library function in gcc

If you have the .a file of your shared library (.so) you can simply include it with its full path as if it was an object file, like this:

This generates main.o by just compiling:

gcc -c main.c

This links that object file with the corresponding static library and creates the executable (named "main"):

gcc main.o mylibrary.a -o main

Or in a single command:

gcc main.c mylibrary.a -o main

It could also be an absolute or relative path:

gcc main.c /usr/local/mylibs/mylibrary.a -o main

Find the index of a dict within a list, by matching the dict's value

Seems most logical to use a filter/index combo:

names=[{}, {'name': 'Tom'},{'name': 'Tony'}]
names.index(filter(lambda n: n.get('name') == 'Tom', names)[0])
1

And if you think there could be multiple matches:

[names.index(n) for item in filter(lambda n: n.get('name') == 'Tom', names)]
[1]

How to add pandas data to an existing csv file?

A bit late to the party but you can also use a context manager, if you're opening and closing your file multiple times, or logging data, statistics, etc.

from contextlib import contextmanager
import pandas as pd
@contextmanager
def open_file(path, mode):
     file_to=open(path,mode)
     yield file_to
     file_to.close()


##later
saved_df=pd.DataFrame(data)
with open_file('yourcsv.csv','r') as infile:
      saved_df.to_csv('yourcsv.csv',mode='a',header=False)`

How do I prevent a form from being resized by the user?

//Set fixed border
yourForm.FormBorderStyle = System.Windows.Forms.FormBorderStyle.Fixed3D

//Set the state of your form to maximized       
yourForm.WindowState = FormWindowState.Maximized

//Disable the minimize box and the maximize box
yourForm.MinimizeBox = False
yourForm.MaximizeBox = False

Importing files from different folder

I was faced with the same challenge, especially when importing multiple files, this is how I managed to overcome it.

import os, sys

from os.path import dirname, join, abspath
sys.path.insert(0, abspath(join(dirname(__file__), '..')))

from root_folder import file_name

Count number of records returned by group by

A CTE worked for me:

with cte as (
  select 1 col1
  from temptable
  group by column_1
)

select COUNT(col1)
from cte;

Jquery to get the id of selected value from dropdown

Try the change event and selected selector

$('#jobSel').change(function(){
    var optId = $(this).find('option:selected').attr('id')
})

Classpath including JAR within a JAR

You need to build a custom class-loader to do this or a third-party library that supports this. Your best bet is to extract the jar from the runtime and add them to the classpath (or have them already added to the classpath).

Octave/Matlab: Adding new elements to a vector

As mentioned before, the use of x(end+1) = newElem has the advantage that it allows you to concatenate your vector with a scalar, regardless of whether your vector is transposed or not. Therefore it is more robust for adding scalars.

However, what should not be forgotten is that x = [x newElem] will also work when you try to add multiple elements at once. Furthermore, this generalizes a bit more naturally to the case where you want to concatenate matrices. M = [M M1 M2 M3]


All in all, if you want a solution that allows you to concatenate your existing vector x with newElem that may or may not be a scalar, this should do the trick:

 x(end+(1:numel(newElem)))=newElem

How do I install PHP cURL on Linux Debian?

Whatever approach you take, make sure in the end that you have an updated version of curl and libcurl. You can do curl --version and see the versions.

Here's what I did to get the latest curl version installed in Ubuntu:

  1. sudo add-apt-repository "deb http://mirrors.kernel.org/ubuntu wily main"
  2. sudo apt-get update
  3. sudo apt-get install curl

Getting session value in javascript

You can access your session variable like '<%= Session["VariableName"]%>'

the text in single quotes will give session value. 1)

<script>
var session ='<%= Session["VariableName"]%>'
</script>

2) you can take a hidden field and assign value at server;

hiddenfield.value= session["xyz"].tostring();

//and in script you access the hiddenfield  like

alert(document.getElementbyId("hiddenfield").value);

Query comparing dates in SQL

Try to use "#" before and after of the date and be sure of your system date format. maybe "YYYYMMDD O YYYY-MM-DD O MM-DD-YYYY O USING '/ O \' "

Ex:

 select id,numbers_from,created_date,amount_numbers,SMS_text 
 from Test_Table
 where 
 created_date <= #2013-04-12#

Is there a way to check for both `null` and `undefined`?

I always write it like this:

var foo:string;

if(!foo){
   foo="something";    
}

This will work fine and I think it's very readable.

How to set an environment variable in a running docker container

If you are running the container as a service using docker swarm, you can do:

docker service update --env-add <you environment variable> <service_name>

Also remove using --env-rm

To make sure it's addedd as you wanted, just run: docker exec -it <container id> env

an htop-like tool to display disk activity in linux

It is not htop-like, but you could use atop. However, to display disk activity per process, it needs a kernel patch (available from the site). These kernel patches are now obsoleted, only to show per-process network activity an optional module is provided.

How to execute a java .class from the command line

Try:

java -cp . Echo "hello"

Assuming that you compiled with:

javac Echo.java 

Then there is a chance that the "current" directory is not in your classpath ( where java looks for .class definitions )

If that's the case and listing the contents of your dir displays:

Echo.java
Echo.class

Then any of this may work:

java -cp . Echo "hello"

or

SET CLASSPATH=%CLASSPATH;.  

java Echo "hello"

And later as Fredrik points out you'll get another error message like.

Exception in thread "main" java.lang.NoSuchMethodError: main

When that happens, go and read his answer :)

Difference between break and continue in PHP?

break will stop the current loop (or pass an integer to tell it how many loops to break from).

continue will stop the current iteration and start the next one.

How to style a JSON block in Github Wiki?

```javascript
{ "some": "json" }
```

I tried using json but didn't like the way it looked. javascript looks a bit more pleasing to my eye.

TypeError: no implicit conversion of Symbol into Integer

Ive come across this many times in my work, an easy work around that I found is to ask if the array element is a Hash by class.

if i.class == Hash

    notation like i[:label] will work in this block and not throw that error

end

How do I remove background-image in css?

If your div rule is just div {...}, then #a {...} will be sufficient. If it is more complicated, you need a "more specific" selector, as defined by the CSS specification on specificity. (#a being more specific than div is just single aspect in the algorithm.)

Using an HTML button to call a JavaScript function

I have an intelligent function-call-backing button code:

<br>
<p id="demo"></p><h2>Intelligent Button:</h2><i>Note: Try pressing a key after clicking.</i><br>
<button id="button" shiftKey="getElementById('button').innerHTML=('You're pressing shift, aren't you?')" onscroll="getElementById('button').innerHTML=('Don't Leave me!')" onkeydown="getElementById('button').innerHTML=('Why are you pressing keys?')" onmouseout="getElementById('button').innerHTML=('Whatever, it is gone.. maybe')" onmouseover="getElementById('button').innerHTML=('Something Is Hovering Over Me.. again')" onclick="getElementById('button').innerHTML=('I was clicked, I think')">Ahhhh</button>

What GRANT USAGE ON SCHEMA exactly do?

For a production system, you can use this configuration :

--ACCESS DB
REVOKE CONNECT ON DATABASE nova FROM PUBLIC;
GRANT  CONNECT ON DATABASE nova  TO user;

--ACCESS SCHEMA
REVOKE ALL     ON SCHEMA public FROM PUBLIC;
GRANT  USAGE   ON SCHEMA public  TO user;

--ACCESS TABLES
REVOKE ALL ON ALL TABLES IN SCHEMA public FROM PUBLIC ;
GRANT SELECT                         ON ALL TABLES IN SCHEMA public TO read_only ;
GRANT SELECT, INSERT, UPDATE, DELETE ON ALL TABLES IN SCHEMA public TO read_write ;
GRANT ALL                            ON ALL TABLES IN SCHEMA public TO admin ;

Select * from subquery

You can select every column from that sub-query by aliasing it and adding the alias before the *:

SELECT t.*, a+b AS total_sum
FROM
(
   SELECT SUM(column1) AS a, SUM(column2) AS b
   FROM table
) t

Popup window in PHP?

PHP runs on the server-side thus you have to use a client-side technology which is capable of showing popup windows: JavaScript.

So you should output a specific JS block via PHP if your form contains errors and you want to show that popup.

Where does SVN client store user authentication data?

I know I'm uprising a very old topic, but after a couple of hours struggling with this very problem and not finding a solution anywhere else, I think this is a good place to put an answer.

We have some Build Servers WindowsXP based and found this very problem: svn command line client is not caching auth credentials.

We finally found out that we are using Cygwin's svn client! not a "native" Windows. So... this client stores all the auth credentials in /home/<user>/.subversion/auth

This /home directory in Cygwin, in our installation is in c:\cygwin\home. AND: the problem was that the Windows user that is running svn did never ever "logged in" in Cygwin, and so there was no /home/<user> directory.

A simple "bash -ls" from a Windows command terminal created the directory, and after the first access to our SVN server with interactive prompting for access credentials, alás, they got cached.

So if you are using Cygwin's svn client, be sure to have a "home" directory created for the local Windows user.

JQuery, setTimeout not working

You've got a couple of issues here.

Firstly, you're defining your code within an anonymous function. This construct:

(function() {
  ...
)();

does two things. It defines an anonymous function and calls it. There are scope reasons to do this but I'm not sure it's what you actually want.

You're passing in a code block to setTimeout(). The problem is that update() is not within scope when executed like that. It however if you pass in a function pointer instead so this works:

(function() {
  $(document).ready(function() {update();});

  function update() { 
    $("#board").append(".");
    setTimeout(update, 1000);     }
  }
)();

because the function pointer update is within scope of that block.

But like I said, there is no need for the anonymous function so you can rewrite it like this:

$(document).ready(function() {update();});

function update() { 
  $("#board").append(".");
  setTimeout(update, 1000);     }
}

or

$(document).ready(function() {update();});

function update() { 
  $("#board").append(".");
  setTimeout('update()', 1000);     }
}

and both of these work. The second works because the update() within the code block is within scope now.

I also prefer the $(function() { ... } shortened block form and rather than calling setTimeout() within update() you can just use setInterval() instead:

$(function() {
  setInterval(update, 1000);
});

function update() {
  $("#board").append(".");
}

Hope that clears that up.

Swapping two variable value without using third variable

Since the original solution is:

temp = x; y = x; x = temp;

You can make it a two liner by using:

temp = x; y = y + temp -(x=y);

Then make it a one liner by using:

x = x + y -(y=x);

Android camera android.hardware.Camera deprecated

API Documentation

According to the Android developers guide for android.hardware.Camera, they state:

We recommend using the new android.hardware.camera2 API for new applications.

On the information page about android.hardware.camera2, (linked above), it is stated:

The android.hardware.camera2 package provides an interface to individual camera devices connected to an Android device. It replaces the deprecated Camera class.

The problem

When you check that documentation you'll find that the implementation of these 2 Camera API's are very different.

For example getting camera orientation on android.hardware.camera

@Override
public int getOrientation(final int cameraId) {
    Camera.CameraInfo info = new Camera.CameraInfo();
    Camera.getCameraInfo(cameraId, info);
    return info.orientation;
}

Versus android.hardware.camera2

@Override
public int getOrientation(final int cameraId) {
    try {
        CameraManager manager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
        String[] cameraIds = manager.getCameraIdList();
        CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraIds[cameraId]);
        return characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);
    } catch (CameraAccessException e) {
        // TODO handle error properly or pass it on
        return 0;
    }
}

This makes it hard to switch from one to another and write code that can handle both implementations.

Note that in this single code example I already had to work around the fact that the olde camera API works with int primitives for camera IDs while the new one works with String objects. For this example I quickly fixed that by using the int as an index in the new API. If the camera's returned aren't always in the same order this will already cause issues. Alternative approach is to work with String objects and String representation of the old int cameraIDs which is probably safer.

One away around

Now to work around this huge difference you can implement an interface first and reference that interface in your code.

Here I'll list some code for that interface and the 2 implementations. You can limit the implementation to what you actually use of the camera API to limit the amount of work.

In the next section I'll quickly explain how to load one or another.

The interface wrapping all you need, to limit this example I only have 2 methods here.

public interface CameraSupport {
    CameraSupport open(int cameraId);
    int getOrientation(int cameraId);
}

Now have a class for the old camera hardware api:

@SuppressWarnings("deprecation")
public class CameraOld implements CameraSupport {

    private Camera camera;

    @Override
    public CameraSupport open(final int cameraId) {
        this.camera = Camera.open(cameraId);
        return this;
    }

    @Override
    public int getOrientation(final int cameraId) {
       Camera.CameraInfo info = new Camera.CameraInfo();
       Camera.getCameraInfo(cameraId, info);
       return info.orientation;
    }
}

And another one for the new hardware api:

public class CameraNew implements CameraSupport {

    private CameraDevice camera;
    private CameraManager manager;

    public CameraNew(final Context context) {
        this.manager = (CameraManager) context.getSystemService(Context.CAMERA_SERVICE);
    }

    @Override
    public CameraSupport open(final int cameraId) {
        try {
            String[] cameraIds = manager.getCameraIdList();
            manager.openCamera(cameraIds[cameraId], new CameraDevice.StateCallback() {
                @Override
                public void onOpened(CameraDevice camera) {
                    CameraNew.this.camera = camera;
                }

                @Override
                public void onDisconnected(CameraDevice camera) {
                    CameraNew.this.camera = camera;
                    // TODO handle
                }

                @Override
                public void onError(CameraDevice camera, int error) {
                    CameraNew.this.camera = camera;
                    // TODO handle
                }
            }, null);
        } catch (Exception e) {
            // TODO handle
        }
        return this;
    }

    @Override
    public int getOrientation(final int cameraId) {
        try {
            String[] cameraIds = manager.getCameraIdList();
            CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraIds[cameraId]);
            return characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION);
        } catch (CameraAccessException e) {
            // TODO handle
            return 0;
        }
    }
}

Loading the proper API

Now to load either your CameraOld or CameraNew class you'll have to check the API level since CameraNew is only available from api level 21.

If you have dependency injection set up already you can do so in your module when providing the CameraSupport implementation. Example:

@Module public class CameraModule {

    @Provides
    CameraSupport provideCameraSupport(){
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            return new CameraNew(context);
        } else {
            return new CameraOld();
        }
    } 
}

If you don't use DI you can just make a utility or use Factory pattern to create the proper one. Important part is that the API level is checked.

Creating a new empty branch for a new project

The best solution is to create a new branch with --orphan option as shown below

git checkout --orphan <branch name>

By this you will be able to create a new branch and directly checkout to the new branch. It will be a parentless branch.

By default the --orphan option doesn't remove the files in the working directory, so you can delete the working directory files by this:

git rm --cached -r

In details what the --orphan does:

--orphan <new_branch>
Create a new orphan branch, named <new_branch>, started from <start_point> and switch to it. The first commit made on this new branch will have no parents and it will be the root of a new history totally disconnected from all the other branches and commits.

The index and the working tree are adjusted as if you had previously run git checkout <start_point>. This allows you to start a new history that records a set of paths similar to <start_point> by easily running git commit -a to make the root commit.

This can be useful when you want to publish the tree from a commit without exposing its full history. You might want to do this to publish an open source branch of a project whose current tree is "clean", but whose full history contains proprietary or otherwise encumbered bits of code.

If you want to start a disconnected history that records a set of paths that is totally different from the one of <start_point>, then you should clear the index and the working tree right after creating the orphan branch by running git rm -rf . from the top level of the working tree. Afterwards you will be ready to prepare your new files, repopulating the working tree, by copying them from elsewhere, extracting a tarball, etc.

Sublime Text 2: How do I change the color that the row number is highlighted?

This post is for Sublime 3.

I just installed Sublime 3, the 64 bit version, on Ubuntu 14.04. I can't tell the difference between this version and Sublime 2 as far as user interface. The reason I didn't go with Sublime 2 is that it gives an annoying "GLib critical" error messages.

Anyways - previous posts mentioned the file /sublime_text_3/Packages/Color\ Scheme\ -\ Default.sublime-package

I wanted to give two tips here with respect to this file in Sublime 3:

  1. You can edit it with pico and use ^W to search the theme name. The first search result will bring you to an XML style entry where you can change the values. Make a copy before you experiment.
  2. If you choose the theme in the sublime menu (under Preferences/Color Scheme) before you change this file, then the changes will be cached and your change will not take effect. So delete the cached version and restart sublime for the changes to take effect. The cached version is at ~/.config/sublime-text-3/Cache/Color Scheme - Default/

How to call on a function found on another file?

Small addition to @user995502's answer on how to run the program.

g++ player.cpp main.cpp -o main.out && ./main.out

How do I get the last word in each line with bash

there are many ways. as awk solutions shows, it's the clean solution

sed solution is to delete anything till the last space. So if there is no space at the end, it should work

sed 's/.* //g' <file>

you can avoid sed also and go for a while loop.

while read line
do [ -z "$line" ] && continue ;
echo $line|rev|cut -f1 -d' '|rev
done < file

it reads a line, reveres it, cuts the first (i.e. last in the original) and restores back

the same can be done in a pure bash way

while read line
do [ -z "$line" ] && continue ;
echo ${line##* }
done < file

it is called parameter expansion

How to concatenate strings in twig

You can use ~ like {{ foo ~ 'inline string' ~ bar.fieldName }}

But you can also create your own concat function to use it like in your question:
{{ concat('http://', app.request.host) }}:

In src/AppBundle/Twig/AppExtension.php

<?php

namespace AppBundle\Twig;

class AppExtension extends \Twig_Extension
{
    /**
     * {@inheritdoc}
     */
    public function getFunctions()
    {
        return [
            new \Twig_SimpleFunction('concat', [$this, 'concat'], ['is_safe' => ['html']]),
        ];
    }

    public function concat()
    {
        return implode('', func_get_args())
    }

    /**
     * {@inheritdoc}
     */
    public function getName()
    {
        return 'app_extension';
    }
}

In app/config/services.yml:

services:
    app.twig_extension:
        class: AppBundle\Twig\AppExtension
        public: false
        tags:
            - { name: twig.extension }

How to redirect back to form with input - Laravel 5

write old function on your fields value for example

<input type="text" name="username" value="{{ old('username') }}">

The given key was not present in the dictionary. Which key?

If you want to manage key misses you should use TryGetValue

https://msdn.microsoft.com/en-gb/library/bb347013(v=vs.110).aspx

string value = "";
if (openWith.TryGetValue("tif", out value))
{
    Console.WriteLine("For key = \"tif\", value = {0}.", value);
}
else
{
    Console.WriteLine("Key = \"tif\" is not found.");
}

"int cannot be dereferenced" in Java

Basically, you're trying to use int as if it was an Object, which it isn't (well...it's complicated)

id.equals(list[pos].getItemNumber())

Should be...

id == list[pos].getItemNumber()

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

I just found a solution to the problem here:

http://willcodeforcoffee.com/2007/01/31/cakephp-error-500-too-many-redirects/

The .htaccess file in webroot should look like:

<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteBase /
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteRule ^(.*)$ index.php?url=$1 [QSA,L]
</IfModule>

instead of this:

<IfModule mod_rewrite.c>
  RewriteEngine On
  RewriteBase /projectname
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteRule ^(.*)$ index.php?url=$1 [QSA,L]
</IfModule>

Display all items in array using jquery

You can do it like this by iterating through the array in a loop, accumulating the new HTML into it's own array and then joining the HTML all together and inserting it into the DOM at the end:

var array = [...];
var newHTML = [];
for (var i = 0; i < array.length; i++) {
    newHTML.push('<span>' + array[i] + '</span>');
}
$(".element").html(newHTML.join(""));

Some people prefer to use jQuery's .each() method instead of the for loop which would work like this:

var array = [...];
var newHTML = [];
$.each(array, function(index, value) {
    newHTML.push('<span>' + value + '</span>');
});
$(".element").html(newHTML.join(""));

Or because the output of the array iteration is itself an array with one item derived from each item in the original array, jQuery's .map can be used like this:

var array = [...];
var newHTML = $.map(array, function(value) {
    return('<span>' + value + '</span>');
});
$(".element").html(newHTML.join(""));

Which you should use is a personal choice depending upon your preferred coding style, sensitivity to performance and familiarity with .map(). My guess is that the for loop would be the fastest since it has fewer function calls, but if performance was the main criteria, then you would have to benchmark the options to actually measure.

FYI, in all three of these options, the HTML is accumulated into an array, then joined together at the end and the inserted into the DOM all at once. This is because DOM operations are usually the slowest part of an operation like this so it's best to minimize the number of separate DOM operations. The results are accumulated into an array because adding items to an array and then joining them at the end is usually faster than adding strings as you go.


And, if you can live with IE9 or above (or install an ES5 polyfill for .map()), you can use the array version of .map like this:

var array = [...];
$(".element").html(array.map(function(value) {
    return('<span>' + value + '</span>');
}).join(""));

Note: this version also gets rid of the newHTML intermediate variable in the interest of compactness.

C++ obtaining milliseconds time on Linux -- clock() doesn't seem to work properly

I prefer the Boost Timer library for its simplicity, but if you don't want to use third-parrty libraries, using clock() seems reasonable.

What does CultureInfo.InvariantCulture mean?

For things like numbers (decimal points, commas in amounts), they are usually preferred in the specific culture.

A appropriate way to do this would be set it at the culture level (for German) like this:

Thread.CurrentThread.CurrentCulture.NumberFormat = new CultureInfo("de").NumberFormat;

Get the correct week number of a given date

Good news! A pull request adding System.Globalization.ISOWeek to .NET Core was just merged and is currently slated for the 3.0 release. Hopefully it will propagate to the other .NET platforms in a not-too-distant future.

The type has the following signature, which should cover most ISO week needs:

namespace System.Globalization
{
    public static class ISOWeek
    {
        public static int GetWeekOfYear(DateTime date);
        public static int GetWeeksInYear(int year);
        public static int GetYear(DateTime date);
        public static DateTime GetYearEnd(int year);
        public static DateTime GetYearStart(int year);
        public static DateTime ToDateTime(int year, int week, DayOfWeek dayOfWeek);
    }
}

You can find the source code here.

UPDATE: These APIs have also been included in the 2.1 version of .NET Standard.

Return outside function error in Python

It basically occours when you return from a loop you can only return from function

How to extract a string using JavaScript Regex?

This code works:

  let str = "governance[string_i_want]"; 
  let res = str.match(/[^governance\[](.*)[^\]]/g);

res will equal "string_i_want". However, in this example res is still an array, so do not treat res like a string.

By grouping the characters I do not want, using [^string], and matching on what is between the brackets, the code extracts the string I want!

You can try it out here: https://www.w3schools.com/jsref/tryit.asp?filename=tryjsref_match_regexp

Good luck.

How do I enable php to work with postgresql?

just install the database driver:

apt-get install php5-pgsql php5-mysql php5-sqlite ... and so on ...

and be happy!

What is the difference between ( for... in ) and ( for... of ) statements?

Difference for..in and for..of:

Both for..in and for..of are looping constructs which are used to iterate over data structures. The only difference between them is the entities they iterate over:

  1. for..in iterates over all enumerable property keys of an object
  2. for..of iterates over the values of an iterable object. Examples of iterable objects are arrays, strings, and NodeLists.

Example:

_x000D_
_x000D_
let arr = ['el1', 'el2', 'el3'];

arr.addedProp = 'arrProp';

// elKey are the property keys
for (let elKey in arr) {
  console.log(elKey);
}

// elValue are the property values
for (let elValue of arr) {
  console.log(elValue)
}
_x000D_
_x000D_
_x000D_

In this example we can observe that the for..in loop iterates over the keys of the object, which is an array object in this example. The keys are 0, 1, 2 (which correspond to the array elements) and addedProp. This is how the arr array object looks in chrome devtools:

enter image description here

You see that our for..in loop does nothing more than simply iterating over these keys.


The for..of loop in our example iterates over the values of a data structure. The values in this specific example are 'el1', 'el2', 'el3'. The values which an iterable data structure will return using for..of is dependent on the type of iterable object. For example an array will return the values of all the array elements whereas a string returns every individual character of the string.

How to use an array list in Java?

A three line solution, but works quite well:

int[] source_array = {0,1,2,3,4,5,6,7,8,9,10,11};
ArrayList<Integer> target_list = new ArrayList<Integer>();
for(int i = 0; i < source_array.length; i++){
    target_list.add(random_array[i]);
}

Package structure for a Java project?

There are a few existing resources you might check:

  1. Properly Package Your Java Classes
  2. Spring 2.5 Architecture
  3. Java Tutorial - Naming a Package
  4. SUN Naming Conventions

For what it's worth, my own personal guidelines that I tend to use are as follows:

  1. Start with reverse domain, e.g. "com.mycompany".
  2. Use product name, e.g. "myproduct". In some cases I tend to have common packages that do not belong to a particular product. These would end up categorized according to the functionality of these common classes, e.g. "io", "util", "ui", etc.
  3. After this it becomes more free-form. Usually I group according to project, area of functionality, deployment, etc. For example I might have "project1", "project2", "ui", "client", etc.

A couple of other points:

  1. It's quite common in projects I've worked on for package names to flow from the design documentation. Usually products are separated into areas of functionality or purpose already.
  2. Don't stress too much about pushing common functionality into higher packages right away. Wait for there to be a need across projects, products, etc., and then refactor.
  3. Watch inter-package dependencies. They're not all bad, but it can signify tight coupling between what might be separate units. There are tools that can help you keep track of this.

What are the differences between type() and isinstance()?

The latter is preferred, because it will handle subclasses properly. In fact, your example can be written even more easily because isinstance()'s second parameter may be a tuple:

if isinstance(b, (str, unicode)):
    do_something_else()

or, using the basestring abstract class:

if isinstance(b, basestring):
    do_something_else()

How to generate a simple popup using jQuery

Check out jQuery UI Dialog. You would use it like this:

The jQuery:

$(document).ready(function() {
    $("#dialog").dialog();
});

The markup:

<div id="dialog" title="Dialog Title">I'm in a dialog</div>

Done!

Bear in mind that's about the simplest use-case there is, I would suggest reading the documentation to get a better idea of just what can be done with it.

Highcharts - redraw() vs. new Highcharts.chart

@RobinL as mentioned in previous comments, you can use chart.series[n].setData(). First you need to make sure you’ve assigned a chart instance to the chart variable, that way it adopts all the properties and methods you need to access and manipulate the chart.

I’ve also used the second parameter of setData() and had it false, to prevent automatic rendering of the chart. This was because I have multiple data series, so I’ll rather update each of them, with render=false, and then running chart.redraw(). This multiplied performance (I’m having 10,000-100,000 data points and refreshing the data set every 50 milliseconds).

Is there a JavaScript strcmp()?

localeCompare() is slow, so if you don't care about the "correct" ordering of non-English-character strings, try your original method or the cleaner-looking:

str1 < str2 ? -1 : +(str1 > str2)

This is an order of magnitude faster than localeCompare() on my machine.

The + ensures that the answer is always numeric rather than boolean.

How to get AIC from Conway–Maxwell-Poisson regression via COM-poisson package in R?

I figured out myself.

cmp calls ComputeBetasAndNuHat which returns a list which has objective as minusloglik

So I can change the function cmp to get this value.

How do I compare 2 rows from the same table (SQL Server)?

You can join a table to itself as many times as you require, it is called a self join.

An alias is assigned to each instance of the table (as in the example below) to differentiate one from another.

SELECT a.SelfJoinTableID
FROM   dbo.SelfJoinTable a
       INNER JOIN dbo.SelfJoinTable b
         ON a.SelfJoinTableID = b.SelfJoinTableID
       INNER JOIN dbo.SelfJoinTable c
         ON a.SelfJoinTableID = c.SelfJoinTableID
WHERE  a.Status = 'Status to filter a'
       AND b.Status = 'Status to filter b'
       AND c.Status = 'Status to filter c' 

How can I add 1 day to current date?

To add one day to a date object:

var date = new Date();

// add a day
date.setDate(date.getDate() + 1);

Can a table row expand and close?

To answer your question, no. That would be possible with div though. THe only question is would cause a hazzle if the functionality were done with div rather than tables.

Where is the default log location for SharePoint/MOSS?

For Sharepoint 2007

C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\LOGS

Markdown `native` text alignment

In Github You need to write:

<p align="justify">
  Lorem ipsum
</p>

Difference between subprocess.Popen and os.system

If you check out the subprocess section of the Python docs, you'll notice there is an example of how to replace os.system() with subprocess.Popen():

sts = os.system("mycmd" + " myarg")

...does the same thing as...

sts = Popen("mycmd" + " myarg", shell=True).wait()

The "improved" code looks more complicated, but it's better because once you know subprocess.Popen(), you don't need anything else. subprocess.Popen() replaces several other tools (os.system() is just one of those) that were scattered throughout three other Python modules.

If it helps, think of subprocess.Popen() as a very flexible os.system().

$_SERVER["REMOTE_ADDR"] gives server IP rather than visitor IP

With PHP 7.4 I do it like this:

$ipaddress = '';
if (isset($_SERVER['REMOTE_ADDR']))
    $ipaddress = $_SERVER['REMOTE_ADDR'];
else if(isset($_SERVER['HTTP_X_FORWARDED_FOR']))
    $ipaddress = $_SERVER['HTTP_X_FORWARDED_FOR'];
else if(isset($_SERVER['HTTP_X_FORWARDED']))
    $ipaddress = $_SERVER['HTTP_X_FORWARDED'];
else if(isset($_SERVER['HTTP_FORWARDED_FOR']))
    $ipaddress = $_SERVER['HTTP_FORWARDED_FOR'];
else if(isset($_SERVER['HTTP_FORWARDED']))
    $ipaddress = $_SERVER['HTTP_FORWARDED'];
else if(isset($_SERVER['HTTP_CLIENT_IP']))
    $ipaddress = $_SERVER['HTTP_CLIENT_IP'];

But keep in mind that REMOTE_ADDR is the only reliable IP address that you can get. All other values can easily be manipulated. This is theoretically also possible for REMOTE_ADDRESS, but that would require to spoof the IP address.

how to use a like with a join in sql?

In MySQL you could try:

SELECT * FROM A INNER JOIN B ON B.MYCOL LIKE CONCAT('%', A.MYCOL, '%');

Of course this would be a massively inefficient query because it would do a full table scan.

Update: Here's a proof


create table A (MYCOL varchar(255));
create table B (MYCOL varchar(255));
insert into A (MYCOL) values ('foo'), ('bar'), ('baz');
insert into B (MYCOL) values ('fooblah'), ('somethingfooblah'), ('foo');
insert into B (MYCOL) values ('barblah'), ('somethingbarblah'), ('bar');
SELECT * FROM A INNER JOIN B ON B.MYCOL LIKE CONCAT('%', A.MYCOL, '%');
+-------+------------------+
| MYCOL | MYCOL            |
+-------+------------------+
| foo   | fooblah          |
| foo   | somethingfooblah |
| foo   | foo              |
| bar   | barblah          |
| bar   | somethingbarblah |
| bar   | bar              |
+-------+------------------+
6 rows in set (0.38 sec)