Programs & Examples On #Truss

Uncaught ReferenceError: $ is not defined

I had the same problem , and I solved by putting jQuery at the top of all javascript codes I have in my code.

Something like this:

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="js/app.js" type="text/javascript"></script>
<script src="js/form.js" type="text/javascript"></script>
<script src="js/create.js" type="text/javascript"></script>
<script src="js/tween.js" type="text/javascript"></script>

Hope can help some one in future.

Can't connect to local MySQL server through socket '/tmp/mysql.sock

I had to kill off all instances of mysql by first finding all the process IDs:

ps aux | grep mysql

And then killing them off:

kill -9 {pid}

Then:

mysql.server start

Worked for me.

How do I change a tab background color when using TabLayout?

One of the ways I could find is using the tab indicator like this:

<com.google.android.material.tabs.TabLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabBackground="@color/normal_unselected_color"
    app:tabIndicatorColor="@color/selected_color"
    app:tabIndicatorGravity="center"
    app:tabIndicatorHeight="150dp"
    app:tabSelectedTextColor="@color/selected_text_color"
    app:tabTextColor="@color/unselected_text_color">

    ..... tab items here .....

</com.google.android.material.tabs.TabLayout>

Trick is to:

  • Make the tab indicator to align in center
  • Make the indicator height sufficiently large so that it covers the whole tab

This also takes care of the smooth animation while switching tabs

variable is not declared it may be inaccessible due to its protection level

This error occurred for me when I mistakenly added a comment following a line continuation character in VB.Net. I removed the comment and the problem went away.

How to use if - else structure in a batch file?

Here's my code Example for if..else..if
which do the following

Prompt user for Process Name

If the process name is invalid
Then it's write to user

Error : The Processor above doesn't seem to be exist 

if the process name is services
Then it's write to user

Error : You can't kill the Processor above 

if the process name is valid and not services
Then it's write to user

the process has been killed via taskill

so i called it Process killer.bat
Here's my Code:

@echo off

:Start
Rem preparing the batch  
cls
Title Processor Killer
Color 0B
Echo Type Processor name to kill It (Without ".exe")
set /p ProcessorTokill=%=%  

:tasklist
tasklist|find /i "%ProcessorTokill%.exe">nul & if errorlevel 1 (
REM check if the process name is invalid 
Cls 
Title %ProcessorTokill% Not Found
Color 0A
echo %ProcessorTokill%
echo Error : The Processor above doesn't seem to be exist    

) else if %ProcessorTokill%==services (
REM check if the process name is services and doesn't kill it
Cls 
Color 0c
Title Permission denied 
echo "%ProcessorTokill%.exe"
echo Error : You can't kill the Processor above 

) else (
REM if the process name is valid and not services
Cls 
Title %ProcessorTokill% Found
Color 0e
echo %ProcessorTokill% Found
ping localhost -n 2 -w 1000>nul
echo Killing %ProcessorTokill% ...
taskkill /f /im %ProcessorTokill%.exe /t>nul
echo %ProcessorTokill% Killed...
)

pause>nul



REM If else if Template
REM if thing1 (
REM Command here 2 ! 
REM ) else if thing2 (
REM command here 2 !
REM ) else (
REM command here 3 !
REM )

Is there any way to call a function periodically in JavaScript?

Old question but.. I also needed a periodical task runner and wrote TaskTimer. This is also useful when you need to run multiple tasks on different intervals.

// Timer with 1000ms (1 second) base interval resolution.
const timer = new TaskTimer(1000);

// Add task(s) based on tick intervals.
timer.add({
    id: 'job1',       // unique id of the task
    tickInterval: 5,    // run every 5 ticks (5 x interval = 5000 ms)
    totalRuns: 10,      // run 10 times only. (set to 0 for unlimited times)
    callback(task) {
        // code to be executed on each run
        console.log(task.id + ' task has run ' + task.currentRuns + ' times.');
    }
});

// Start the timer
timer.start();

TaskTimer works both in browser and Node. See documentation for all features.

Installing MySQL in Docker fails with error message "Can't connect to local MySQL server through socket"

I had the same problem, in fact, I juste forgot to run the service after installation ..

Start mysql server :

/etc/init.d/mysql start

How to install MinGW-w64 and MSYS2?

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

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

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

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

  3. Install a toolchain

    a) for 32-bit:

    pacman -S mingw-w64-i686-gcc
    

    b) for 64-bit:

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

    pacman -Ss name_of_something_i_want_to_install
    

    e.g.

    pacman -Ss gsl
    

    and install using

    pacman -S package_name_of_something_i_want_to_install
    

    e.g.

    pacman -S mingw-w64-x86_64-gsl
    

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

  5. Open a MinGW-w64 shell:

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

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

  6. Verify that the compiler is working by doing

    gcc -v
    

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

Maximum size of an Array in Javascript

I have built a performance framework that manipulates and graphs millions of datasets, and even then, the javascript calculation latency was on order of tens of milliseconds. Unless you're worried about going over the array size limit, I don't think you have much to worry about.

SQLAlchemy default DateTime

You likely want to use onupdate=datetime.now so that UPDATEs also change the last_updated field.

SQLAlchemy has two defaults for python executed functions.

  • default sets the value on INSERT, only once
  • onupdate sets the value to the callable result on UPDATE as well.

python object() takes no parameters error

You've mixed tabs and spaces. __init__ is actually defined nested inside another method, so your class doesn't have its own __init__ method, and it inherits object.__init__ instead. Open your code in Notepad instead of whatever editor you're using, and you'll see your code as Python's tab-handling rules see it.

This is why you should never mix tabs and spaces. Stick to one or the other. Spaces are recommended.

Getting the last revision number in SVN?

You can use the XML out format, for example:

  svn info --xml | grep 'revision' | head -1 | grep -Eo "[0-9]+" | xargs expr -1 +

Example: using the revision number

working=`svn info --xml | grep 'revision' | head -1 | grep -Eo "[0-9]+" | xargs expr -1 +`
svn diff -r $working:HEAD --summarize --xml

How to Select Top 100 rows in Oracle?

To select top n rows updated recently

SELECT * 
FROM (
   SELECT * 
   FROM table 
   ORDER BY UpdateDateTime DESC
)
WHERE ROWNUM < 101;

Is there an onSelect event or equivalent for HTML <select>?

The wonderful thing about the select tag (in this scenario) is that it will grab its value from the option tags.

Try:

<select onChange="javascript:doSomething(this.value);">
<option value="A">A</option>
<option value="B">B</option>
<option value="Foo">C</option>
</select>

Worked decent for me.

Django gives Bad Request (400) when DEBUG = False

I had the same problem and none of the answers resolved my problem, for resolving the situation like this it's better to enable logging by adding the following config to settings.py temporary

LOGGING = { 'version': 1, 'disable_existing_loggers': False, 'handlers': { 'file': { 'level': 'DEBUG', 'class': 'logging.FileHandler', 'filename': '/tmp/debug.log', }, }, 'loggers': { 'django': { 'handlers': ['file'], 'level': 'DEBUG', 'propagate': True, }, }, }

and try to tail -f /tmp/debug.log. and when you see your issue you can handle it much easier than blind debugging.

My issue was about to

Invalid HTTP_HOST header: 'pt_web:8000'. The domain name provided is not valid according to RFC 1034/1035.

and resolve it by adding proxy_set_header Host $host; to Nginx config file and enabling port forwarding by USE_X_FORWARDED_PORT = True in the settings.py ( it's because in my case I've listened to request in Nginx on port 8080 and pass it to guni on port 8000

S3 - Access-Control-Allow-Origin Header

See above answers. (but I had a chrome bug too)

Don't load and display the image on the page in CHROME. (if you are going to later create a new instance)

In my case, I loaded images and displayed them on the page. When they were clicked, I created a new instance of them:

// there is already an html <img /> on the page, I'm creating a new one now
img = $('<img crossorigin />')[0]
img.onload = function(){
  context.drawImage(img, 0, 0)
  context.getImageData(0,0,w,h)
}
img.src = 'http://s3.amazonaws.com/my/image.png'; // I added arbitrary ?crossorigin to change the URL of this to fix it

Chrome had already cached another version and NEVER tried to re-fetch the crossorigin version(even if I was using crossorigin on the displayed images.

To fix, I added ?crossorigin to the end of the image url(but you could add ?blah, it's just arbitrary to change the cache status) when I loaded it for canvas.. Let me know if you find a better fix for CHROME

C# get and set properties for a List Collection

Or

public class Section
{
  public String Head { get; set; }
  private readonly List<string> _subHead = new List<string>();
  private readonly List<string> _content = new List<string>();

  public IEnumerable<string> SubHead { get { return _subHead; } }
  public IEnumerable<string> Content { get { return _content; } }

  public void AddContent(String argValue)
  {
    _content.Add(argValue);
  }

  public void AddSubHeader(String argValue)
  {
    _subHead.Add(argValue);
  }
}

All depends on how much of the implementaton of content and subhead you want to hide.

C# : changing listbox row color?

You will need to draw the item yourself. Change the DrawMode to OwnerDrawFixed and handle the DrawItem event.

/// <summary>
/// Handles the DrawItem event of the listBox1 control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.Windows.Forms.DrawItemEventArgs"/> instance containing the event data.</param>
private void listBox1_DrawItem( object sender, DrawItemEventArgs e )
{
   e.DrawBackground();
   Graphics g = e.Graphics;

    // draw the background color you want
    // mine is set to olive, change it to whatever you want
    g.FillRectangle( new SolidBrush( Color.Olive), e.Bounds );

    // draw the text of the list item, not doing this will only show
    // the background color
    // you will need to get the text of item to display
    g.DrawString( THE_LIST_ITEM_TEXT , e.Font, new SolidBrush( e.ForeColor ), new PointF( e.Bounds.X, e.Bounds.Y) );

    e.DrawFocusRectangle();
}

Cannot issue data manipulation statements with executeQuery()

When executing DML statement , you should use executeUpdate/execute rather than executeQuery.

Here is a brief comparison :

executeQueryVSexecuteUpdateVSexecute

C# catch a stack overflow exception

It's impossible, and for a good reason (for one, think about all those catch(Exception){} around).

If you want to continue execution after stack overflow, run dangerous code in a different AppDomain. CLR policies can be set to terminate current AppDomain on overflow without affecting original domain.

Cannot declare instance members in a static class in C#

Have you tried using the 'static' storage class similar to?:

public static class employee
{
    static NameValueCollection appSetting = ConfigurationManager.AppSettings;    
}

Python list sort in descending order

You can simply do this:

timestamps.sort(reverse=True)

How do I change the figure size with subplots?

Alternatively, create a figure() object using the figsize argument and then use add_subplot to add your subplots. E.g.

import matplotlib.pyplot as plt
import numpy as np

f = plt.figure(figsize=(10,3))
ax = f.add_subplot(121)
ax2 = f.add_subplot(122)
x = np.linspace(0,4,1000)
ax.plot(x, np.sin(x))
ax2.plot(x, np.cos(x), 'r:')

Simple Example

Benefits of this method are that the syntax is closer to calls of subplot() instead of subplots(). E.g. subplots doesn't seem to support using a GridSpec for controlling the spacing of the subplots, but both subplot() and add_subplot() do.

Pass in an array of Deferreds to $.when()

When calling multiple parallel AJAX calls, you have two options for handling the respective responses.

  1. Use Synchronous AJAX call/ one after another/ not recommended
  2. Use Promises' array and $.when which accepts promises and its callback .done gets called when all the promises are return successfully with respective responses.

Example

_x000D_
_x000D_
function ajaxRequest(capitalCity) {_x000D_
   return $.ajax({_x000D_
        url: 'https://restcountries.eu/rest/v1/capital/'+capitalCity,_x000D_
        success: function(response) {_x000D_
        },_x000D_
        error: function(response) {_x000D_
          console.log("Error")_x000D_
        }_x000D_
    });_x000D_
}_x000D_
$(function(){_x000D_
   var capitalCities = ['Delhi', 'Beijing', 'Washington', 'Tokyo', 'London'];_x000D_
   $('#capitals').text(capitalCities);_x000D_
_x000D_
   function getCountryCapitals(){ //do multiple parallel ajax requests_x000D_
      var promises = [];   _x000D_
      for(var i=0,l=capitalCities.length; i<l; i++){_x000D_
            var promise = ajaxRequest(capitalCities[i]);_x000D_
            promises.push(promise);_x000D_
      }_x000D_
  _x000D_
      $.when.apply($, promises)_x000D_
        .done(fillCountryCapitals);_x000D_
   }_x000D_
  _x000D_
   function fillCountryCapitals(){_x000D_
        var countries = [];_x000D_
        var responses = arguments;_x000D_
        for(i in responses){_x000D_
            console.dir(responses[i]);_x000D_
            countries.push(responses[i][0][0].nativeName)_x000D_
        }  _x000D_
        $('#countries').text(countries);_x000D_
   }_x000D_
  _x000D_
   getCountryCapitals()_x000D_
})
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>_x000D_
<div>_x000D_
  <h4>Capital Cities : </h4> <span id="capitals"></span>_x000D_
  <h4>Respective Country's Native Names : </h4> <span id="countries"></span>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Daemon Threads Explanation

When your second thread is non-Daemon, your application's primary main thread cannot quit because its exit criteria is being tied to the exit also of non-Daemon thread(s). Threads cannot be forcibly killed in python, therefore your app will have to really wait for the non-Daemon thread(s) to exit. If this behavior is not what you want, then set your second thread as daemon so that it won't hold back your application from exiting.

How do I force make/GCC to show me the commands?

Since GNU Make version 4.0, the --trace argument is a nice way to tell what and why a makefile do, outputing lines like:

makefile:8: target 'foo.o' does not exist

or

makefile:12: update target 'foo' due to: bar

What evaluates to True/False in R?

If you think about it, comparing numbers to logical statements doesn't make much sense. However, since 0 is often associated with "Off" or "False" and 1 with "On" or "True", R has decided to allow 1 == TRUE and 0 == FALSE to both be true. Any other numeric-to-boolean comparison should yield false, unless it's something like 3 - 2 == TRUE.

How do I clone a subdirectory only of a Git repository?

If you never plan to interact with the repository from which you cloned, you can do a full git clone and rewrite your repository using git filter-branch --subdirectory-filter. This way, at least the history will be preserved.

How to get value by key from JObject?

You can also get the value of an item in the jObject like this:

JToken value;
if (json.TryGetValue(key, out value))
{
   DoSomething(value);
}

How can I protect my .NET assemblies from decompilation?

How to preventing decompilation of any C# application

Pretty much describes the entire situation.

At some point the code will have to be translated to VM bytecode, and the user can get at it then.

Machine code isn't that much different either. A good interactive disassembler/debugger like IDA Pro makes just about any native application transparent. The debugger is smart enough to use AI to identify common APIs, compiler optimizations, etc. it allows the user to meticuloulsy rebuild higher level constructs from the assembly generated from machine code.

And IDA Pro supports .Net to some extent too.

Honestly, after working on an reverse engineering ( for compatibility ) project for a few years, the main thing I got out of my experience is that I probably shouldn't worry too much about people stealing my code. If anyone wants it, it will never be very hard to get it no matter what scheme I implement.

How do you remove Subversion control for a folder?

Try svn export.

You should be able to do something like this:

svn export /path/to/old/working/copy /path/to/plain/code

And then just delete the old working copy.

TortoiseSVN also has an export feature, which behaves the same way.

How to get absolute value from double - c-language

It's worth noting that Java can overload a method such as abs so that it works with an integer or a double. In C, overloading doesn't exist, so you need different functions for integer versus double.

OSX -bash: composer: command not found

this wasted me a day or two. like why dont anybody say on tutorials that the command composer is not to be used without actually linking and stuff... I mean everyone is writing composer command like its the next step when we are not all 5 years experienced users to know these details.

cp composer.phar /usr/local/bin/composer

did it for me on ubuntu after getting stuck for 2 days

jQuery Ajax error handling, show custom exception messages

Throw a new exception on server using:

Response.StatusCode = 500

Response.StatusDescription = ex.Message()

I believe that the StatusDescription is returned to the Ajax call...

Example:

        Try

            Dim file As String = Request.QueryString("file")

            If String.IsNullOrEmpty(file) Then Throw New Exception("File does not exist")

            Dim sTmpFolder As String = "Temp\" & Session.SessionID.ToString()

            sTmpFolder = IO.Path.Combine(Request.PhysicalApplicationPath(), sTmpFolder)

            file = IO.Path.Combine(sTmpFolder, file)

            If IO.File.Exists(file) Then

                IO.File.Delete(file)

            End If

        Catch ex As Exception

            Response.StatusCode = 500

            Response.StatusDescription = ex.Message()

        End Try

Reload parent window from child window

Prevents previous data from been resubmitted. Tested in Firefox and Safari.

top.frames.location.href = top.frames.location.href;

Return file in ASP.Net Core Web API

If this is ASP.net-Core then you are mixing web API versions. Have the action return a derived IActionResult because in your current code the framework is treating HttpResponseMessage as a model.

[Route("api/[controller]")]
public class DownloadController : Controller {
    //GET api/download/12345abc
    [HttpGet("{id}"]
    public async Task<IActionResult> Download(string id) {
        Stream stream = await {{__get_stream_based_on_id_here__}}

        if(stream == null)
            return NotFound(); // returns a NotFoundResult with Status404NotFound response.

        return File(stream, "application/octet-stream"); // returns a FileStreamResult
    }    
}

How to render a DateTime object in a Twig template

you can render in following way

{{ post.published_at|date("m/d/Y") }}

For more details can visit http://twig.sensiolabs.org/doc/filters/date.html

Java double.MAX_VALUE?

Double.MAX_VALUE is the maximum value a double can represent (somewhere around 1.7*10^308).

This should end in some calculation problems, if you try to subtract the maximum possible value of a data type.

Even though when you are dealing with money you should never use floating point values especially while rounding this can cause problems (you will either have to much or less money in your system then).

Numbering rows within groups in a data frame

Here is a small improvement trick that allows sort 'val' inside the groups:

# 1. Data set
set.seed(100)
df <- data.frame(
  cat = c(rep("aaa", 5), rep("ccc", 5), rep("bbb", 5)), 
  val = runif(15))             

# 2. 'dplyr' approach
df %>% 
  arrange(cat, val) %>% 
  group_by(cat) %>% 
  mutate(id = row_number())

Stretch background image css?

.style1 {
  background: url(images/bg.jpg) no-repeat center center fixed;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}

Works in:

  • Safari 3+
  • Chrome Whatever+
  • IE 9+
  • Opera 10+ (Opera 9.5 supported background-size but not the keywords)
  • Firefox 3.6+ (Firefox 4 supports non-vendor prefixed version)

In addition you can try this for an IE solution

filter: progid:DXImageTransform.Microsoft.AlphaImageLoader(src='.myBackground.jpg', sizingMethod='scale');
-ms-filter: "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='myBackground.jpg', sizingMethod='scale')";
zoom: 1;

Credit to this article by Chris Coyier http://css-tricks.com/perfect-full-page-background-image/

XPath to select Element by attribute value

You need to remove the / before the [. Predicates (the parts in [ ]) shouldn't have slashes immediately before them. Also, to select the Employee element itself, you should leave off the /text() at the end or otherwise you'd just be selecting the whitespace text values immediately under the Employee element.

//Employee[@id='4']

Edit: As Jens points out in the comments, // can be very slow because it searches the entire document for matching nodes. If the structure of the documents you're working with is going to be consistent, you are probably best off using a full path, for example:

/Employees/Employee[@id='4']

Can we open pdf file using UIWebView on iOS?

NSString *path = [[NSBundle mainBundle] pathForResource:@"document" ofType:@"pdf"];
NSURL *targetURL = [NSURL fileURLWithPath:path];
NSURLRequest *request = [NSURLRequest requestWithURL:targetURL];
[webView loadRequest:request];

What's the pythonic way to use getters and setters?

Try this: Python Property

The sample code is:

class C(object):
    def __init__(self):
        self._x = None

    @property
    def x(self):
        """I'm the 'x' property."""
        print("getter of x called")
        return self._x

    @x.setter
    def x(self, value):
        print("setter of x called")
        self._x = value

    @x.deleter
    def x(self):
        print("deleter of x called")
        del self._x


c = C()
c.x = 'foo'  # setter called
foo = c.x    # getter called
del c.x      # deleter called

How to style icon color, size, and shadow of Font Awesome Icons

Simply you can define a class in your css file and cascade it into html file like

<i class="fa fa-plus fa-lg green"></i> 

now write down in css

.green{ color:green}

How should I read a file line-by-line in Python?

if you're turned off by the extra line, you can use a wrapper function like so:

def with_iter(iterable):
    with iterable as iter:
        for item in iter:
            yield item

for line in with_iter(open('...')):
    ...

in Python 3.3, the yield from statement would make this even shorter:

def with_iter(iterable):
    with iterable as iter:
        yield from iter

Give all permissions to a user on a PostgreSQL database

GRANT USAGE ON SCHEMA schema_name TO user;

How to increment a JavaScript variable using a button press event

I believe you need something similar to the following:

<script type="text/javascript">
var count;
function increment(){
    count++;
}
</script>

...

and

<input type="button" onClick="increment()" value="Increment"/>

or

<input type="button" onClick="count++" value="Increment"/>

Install apps silently, with granted INSTALL_PACKAGES permission

I have been implementing installation without user consent recently - it was a kiosk application for API level 21+ where I had full control over environment.

The basic requirements are

  • API level 21+
  • root access to install the updater as a system privileged app.

The following method reads and installs APK from InputStream:

public static boolean installPackage(Context context, InputStream in, String packageName)
            throws IOException {
        PackageInstaller packageInstaller = context.getPackageManager().getPackageInstaller();
        PackageInstaller.SessionParams params = new PackageInstaller.SessionParams(
                PackageInstaller.SessionParams.MODE_FULL_INSTALL);
        params.setAppPackageName(packageName);
        // set params
        int sessionId = packageInstaller.createSession(params);
        PackageInstaller.Session session = packageInstaller.openSession(sessionId);
        OutputStream out = session.openWrite("COSU", 0, -1);
        byte[] buffer = new byte[65536];
        int c;
        while ((c = in.read(buffer)) != -1) {
            out.write(buffer, 0, c);
        }
        session.fsync(out);
        in.close();
        out.close();

        Intent intent = new Intent(context, MainActivity.class);
        intent.putExtra("info", "somedata");  // for extra data if needed..

        Random generator = new Random();

        PendingIntent i = PendingIntent.getActivity(context, generator.nextInt(), intent,PendingIntent.FLAG_UPDATE_CURRENT);
            session.commit(i.getIntentSender());


        return true;
    }

The following code calls the installation

 try {
     InputStream is = getResources().openRawResource(R.raw.someapk_source);
                    installPackage(MainActivity.this, is, "com.example.apk");
     } catch (IOException e) {
                    Toast.makeText(MainActivity.this, e.getMessage(), Toast.LENGTH_SHORT).show();
     }

for the whole thing to work you desperately need INSTALL_PACKAGES permission, or the code above will fail silently

<uses-permission
        android:name="android.permission.INSTALL_PACKAGES" />

to get this permission you must install your APK as System application which REQUIRES root (however AFTER you have installed your updater application it seem to work WITHOUT root)

To install as system application I created a signed APK and pushed it with

adb push updater.apk /sdcard/updater.apk

and then moved it to system/priv-app - which requires remounting FS (this is why the root is required)

adb shell
su
mount -o rw,remount /system
mv /sdcard/updater.apk /system/priv-app
chmod 644 /system/priv-app/updater.apk

for some reason it didn't work with simple debug version, but logcat shows useful info if your application in priv-app is not picked up for some reason.

Changing button text onclick

this can be done easily with a vbs code (as i'm not so familiar with js )

<input type="button" id="btn" Value="Close" onclick="check">
<script Language="VBScript">
sub check
if btn.Value="Close" then btn.Value="Open" 
end sub
</script>

and you're done , however this changes the Name to display only and does not change the function {onclick} , i did some researches on how to do the second one and seem there isnt' something like

btn.onclick = ".."

but i figured out a way using <"span"> tag it goes like this :

<script Language="VBScript">
  Sub function1
  MsgBox "function1"
  span.InnerHTML= "<Input type=""button"" Value=""button2"" onclick=""function2"">"
  End Sub

   Sub function2
  MsgBox "function2"
  span.InnerHTML = "<Input type=""button"" Value=""button1"" onclick=""function1"">"
  End Sub
  </script>
  <body>
  <span id="span" name="span" >
  <input type="button" Value="button1" onclick="function1">
  </span>
  </body>

try it yourself , change the codes in sub function1 and sub function2, basically all you need to know to make it in jscript is the line

span.InnerHTML = "..." 

the rest is your code you wanna execute

hope this helps :D

Set IDENTITY_INSERT ON is not working

In VB code, when trying to submit an INSERT query, you must submit a double query in the same 'executenonquery' like this:

sqlQuery = "SET IDENTITY_INSERT dbo.TheTable ON; INSERT INTO dbo.TheTable (Col1, COl2) VALUES (Val1, Val2); SET IDENTITY_INSERT dbo.TheTable OFF;"

I used a ; separator instead of a GO.

Works for me. Late but efficient!

how to create a logfile in php?

Please check with this documentation.

http://php.net/manual/en/function.error-log.php

Example:

<?php
// Send notification through the server log if we can not
// connect to the database.
if (!Ora_Logon($username, $password)) {
    error_log("Oracle database not available!", 0);
}

// Notify administrator by email if we run out of FOO
if (!($foo = allocate_new_foo())) {
    error_log("Big trouble, we're all out of FOOs!", 1,
               "[email protected]");
}

// another way to call error_log():
error_log("You messed up!", 3, "/var/tmp/my-errors.log");
?>

How do I choose the URL for my Spring Boot webapp?

As of spring boot 2 the server.contextPath property is deprecated. Instead you should use server.servlet.contextPath.

So in your application.properties file add:

server.servlet.contextPath=/myWebApp

For more details see: https://github.com/spring-projects/spring-boot/wiki/Spring-Boot-2.0-Migration-Guide#servlet-specific-server-properties

How to get the last element of an array in Ruby?

Use -1 index (negative indices count backward from the end of the array):

a[-1] # => 5
b[-1] # => 6

or Array#last method:

a.last # => 5
b.last # => 6

Pandas - replacing column values

You can also try using apply with get method of dictionary, seems to be little faster than replace:

data['sex'] = data['sex'].apply({1:'Male', 0:'Female'}.get)

Testing with timeit:

%%timeit
data['sex'].replace([0,1],['Female','Male'],inplace=True)

Result:

The slowest run took 5.83 times longer than the fastest. This could mean that an intermediate result is being cached.
1000 loops, best of 3: 510 µs per loop

Using apply:

%%timeit
data['sex'] = data['sex'].apply({1:'Male', 0:'Female'}.get)

Result:

The slowest run took 5.92 times longer than the fastest. This could mean that an intermediate result is being cached.
1000 loops, best of 3: 331 µs per loop

Note: apply with dictionary should be used if all the possible values of the columns in the dataframe are defined in the dictionary else, it will have empty for those not defined in dictionary.

Removing certain characters from a string in R

This should work

gsub('\u009c','','\u009cYes yes for ever for ever the boys ')
"Yes yes for ever for ever the boys "

Here 009c is the hexadecimal number of unicode. You must always specify 4 hexadecimal digits. If you have many , one solution is to separate them by a pipe:

gsub('\u009c|\u00F0','','\u009cYes yes \u00F0for ever for ever the boys and the girls')

"Yes yes for ever for ever the boys and the girls"

How to trigger checkbox click event even if it's checked through Javascript code?

You can use the jQuery .trigger() method. See http://api.jquery.com/trigger/

E.g.:

$('#foo').trigger('click');

Stored Procedure error ORA-06550

Could you try this one:

create or replace 
procedure point_triangle
IS
BEGIN
  FOR thisteam in (select P.FIRSTNAME,P.LASTNAME, SUM(P.PTS) S from PLAYERREGULARSEASON P  where P.TEAM = 'IND'  group by P.FIRSTNAME, P.LASTNAME order by SUM(P.PTS) DESC)
  LOOP
    dbms_output.put_line(thisteam.FIRSTNAME|| ' ' || thisteam.LASTNAME  || ':' || thisteam.S);
  END LOOP;

END;

Define an <img>'s src attribute in CSS

After trying these solutions I still wasn't satisfied but I found a solution in this article and it works in Chrome, Firefox, Opera, Safari, IE8+

#divId {

  display: block;
  -moz-box-sizing: border-box;
  box-sizing: border-box;
  background: url(http://notrealdomain2.com/newbanner.png) no-repeat;
  width: 180px; /* Width of new image */
  height: 236px; /* Height of new image */
  padding-left: 180px; /* Equal to width of new image */

}

Iterating a JavaScript object's properties using jQuery

You can use each for objects too and not just for arrays:

var obj = {
    foo: "bar",
    baz: "quux"
};
jQuery.each(obj, function(name, value) {
    alert(name + ": " + value);
});

for each loop in Objective-C for accessing NSMutable dictionary

Just to not leave out the 10.6+ option for enumerating keys and values using blocks...

[dict enumerateKeysAndObjectsUsingBlock:^(id key, id object, BOOL *stop) {
    NSLog(@"%@ = %@", key, object);
}];

If you want the actions to happen concurrently:

[dict enumerateKeysAndObjectsWithOptions:NSEnumerationConcurrent
                              usingBlock:^(id key, id object, BOOL *stop) {
    NSLog(@"%@ = %@", key, object);
}];

How to create an ArrayList from an Array in PowerShell?

Probably the shortest version:

[System.Collections.ArrayList]$someArray

It is also faster because it does not call relatively expensive New-Object.

Authentication failed for https://xxx.visualstudio.com/DefaultCollection/_git/project

With VSTS the url is, When you copy git clone url from vsts you always get

https://orgname@dev.azure.com/org/project/_git/repo

Replace orgname@ with your alternate username that you would have created in VSTS -> profile -> Security.

final git url -

https://alternateusername@dev.azure.com/org/project/_git/repo

What is the use of the JavaScript 'bind' method?

/**
 * Bind is a method inherited from Function.prototype same like call and apply
 * It basically helps to bind a function to an object's context during initialisation 
 * 
 * */

window.myname = "Jineesh";  
var foo = function(){ 
  return this.myname;
};

//IE < 8 has issues with this, supported in ecmascript 5
var obj = { 
    myname : "John", 
    fn:foo.bind(window)// binds to window object
}; 
console.log( obj.fn() ); // Returns Jineesh

Add Items to Columns in a WPF ListView

Solution With Less XAML and More C#

If you define the ListView in XAML:

<ListView x:Name="listView"/>

Then you can add columns and populate it in C#:

public Window()
{
    // Initialize
    this.InitializeComponent();

    // Add columns
    var gridView = new GridView();
    this.listView.View = gridView;
    gridView.Columns.Add(new GridViewColumn { 
        Header = "Id", DisplayMemberBinding = new Binding("Id") });
    gridView.Columns.Add(new GridViewColumn { 
        Header = "Name", DisplayMemberBinding = new Binding("Name") });

    // Populate list
    this.listView.Items.Add(new MyItem { Id = 1, Name = "David" });
}

See definition of MyItem below.

Solution With More XAML and less C#

However, it's easier to define the columns in XAML (inside the ListView definition):

<ListView x:Name="listView">
    <ListView.View>
        <GridView>
            <GridViewColumn Header="Id" DisplayMemberBinding="{Binding Id}"/>
            <GridViewColumn Header="Name" DisplayMemberBinding="{Binding Name}"/>
        </GridView>
    </ListView.View>
</ListView>

And then just populate the list in C#:

public Window()
{
    // Initialize
    this.InitializeComponent();

    // Populate list
    this.listView.Items.Add(new MyItem { Id = 1, Name = "David" });
}

See definition of MyItem below.

MyItem Definition

MyItem is defined like this:

public class MyItem
{
    public int Id { get; set; }

    public string Name { get; set; }
}

Oracle insert from select into table with more columns

Put 0 as default in SQL or add 0 into your area of table

How to do a join in linq to sql with method syntax?

Justin has correctly shown the expansion in the case where the join is just followed by a select. If you've got something else, it becomes more tricky due to transparent identifiers - the mechanism the C# compiler uses to propagate the scope of both halves of the join.

So to change Justin's example slightly:

var result = from sc in enumerableOfSomeClass
             join soc in enumerableOfSomeOtherClass
             on sc.Property1 equals soc.Property2
             where sc.X + sc.Y == 10
             select new { SomeClass = sc, SomeOtherClass = soc }

would be converted into something like this:

var result = enumerableOfSomeClass
    .Join(enumerableOfSomeOtherClass,
          sc => sc.Property1,
          soc => soc.Property2,
          (sc, soc) => new { sc, soc })
    .Where(z => z.sc.X + z.sc.Y == 10)
    .Select(z => new { SomeClass = z.sc, SomeOtherClass = z.soc });

The z here is the transparent identifier - but because it's transparent, you can't see it in the original query :)

Writing MemoryStream to Response Object

First We Need To Write into our Memory Stream and then with the help of Memory Stream method "WriteTo" we can write to the Response of the Page as shown in the below code.

   MemoryStream filecontent = null;
   filecontent =//CommonUtility.ExportToPdf(inputXMLtoXSLT);(This will be your MemeoryStream Content)
   Response.ContentType = "image/pdf";
   string headerValue = string.Format("attachment; filename={0}", formName.ToUpper() + ".pdf");
   Response.AppendHeader("Content-Disposition", headerValue);

   filecontent.WriteTo(Response.OutputStream);

   Response.End();

FormName is the fileName given,This code will make the generated PDF file downloadable by invoking a PopUp.

Sample settings.xml

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

License:

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

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

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

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

Main docs and top:

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

Local repository, interactive mode, plugin groups:

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

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

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

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

Proxies:

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

Servers:

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

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

Mirrors:

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

Profiles (1/3):

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

Profiles (2/3):

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

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

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

Profiles (3/3):

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

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

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

Bottom:

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

Complete file:


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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Pretty-Printing JSON with PHP

Have color full output: Tiny Solution

Code:

$s = '{"access": {"token": {"issued_at": "2008-08-16T14:10:31.309353", "expires": "2008-08-17T14:10:31Z", "id": "MIICQgYJKoZIhvcIegeyJpc3N1ZWRfYXQiOiAi"}, "serviceCatalog": [], "user": {"username": "ajay", "roles_links": [], "id": "16452ca89", "roles": [], "name": "ajay"}}}';

$crl = 0;
$ss = false;
echo "<pre>";
for($c=0; $c<strlen($s); $c++)
{
    if ( $s[$c] == '}' || $s[$c] == ']' )
    {
        $crl--;
        echo "\n";
        echo str_repeat(' ', ($crl*2));
    }
    if ( $s[$c] == '"' && ($s[$c-1] == ',' || $s[$c-2] == ',') )
    {
        echo "\n";
        echo str_repeat(' ', ($crl*2));
    }
    if ( $s[$c] == '"' && !$ss )
    {
        if ( $s[$c-1] == ':' || $s[$c-2] == ':' )
            echo '<span style="color:#0000ff;">';
        else
            echo '<span style="color:#ff0000;">';
    }
    echo $s[$c];
    if ( $s[$c] == '"' && $ss )
        echo '</span>';
    if ( $s[$c] == '"' )
          $ss = !$ss;
    if ( $s[$c] == '{' || $s[$c] == '[' )
    {
        $crl++;
        echo "\n";
        echo str_repeat(' ', ($crl*2));
    }
}
echo $s[$c];

How to Copy Text to Clip Board in Android?

As a handy kotlin extension:

fun Context.copyToClipboard(text: CharSequence){
    val clipboard = getSystemService(Context.CLIPBOARD_SERVICE) as ClipboardManager
    val clip = ClipData.newPlainText("label",text)
    clipboard.setPrimaryClip(clip)
}

Update:

If you using ContextCompat you should use:

ContextCompat.getSystemService(this, ClipboardManager::class.java)

Why am I getting "undefined reference to sqrt" error even though I include math.h header?

You need to link the with the -lm linker option

You need to compile as

gcc test.c  -o test -lm

gcc (Not g++) historically would not by default include the mathematical functions while linking. It has also been separated from libc onto a separate library libm. To link with these functions you have to advise the linker to include the library -l linker option followed by the library name m thus -lm.

PHP Multiple Checkbox Array

Try this, by for Loop

<form method="post">
<?php
for ($i=1; $i <5 ; $i++) 
{ 
    echo'<input type="checkbox" value="'.$i.'" name="checkbox[]"/>';
} 
?>
<input type="submit" name="submit" class="form-control" value="Submit">  
</form>

<?php 
if(isset($_POST['submit']))
{
    $check=implode(", ", $_POST['checkbox']);
    print_r($check);
}     
?>

How to restart counting from 1 after erasing table in MS Access?

In addition to all the concerns expressed about why you give a rat's ass what the ID value is (all are correct that you shouldn't), let me add this to the mix:

If you've deleted all the records from the table, compacting the database will reset the seed value back to its original value.

For a table where there are still records, and you've inserted a value into the Autonumber field that is lower than the highest value, you have to use @Remou's method to reset the seed value. This also applies if you want to reset to the Max+1 in a table where records have been deleted, e.g., 300 records, last ID of 300, delete 201-300, compact won't reset the counter (you have to use @Remou's method -- this was not the case in earlier versions of Jet, and, indeed, in early versions of Jet 4, the first Jet version that allowed manipulating the seed value programatically).

google map API zoom range

Available Zoom Levels

Zoom level 0 is the most zoomed out zoom level available and each integer step in zoom level halves the X and Y extents of the view and doubles the linear resolution.

Google Maps was built on a 256x256 pixel tile system where zoom level 0 was a 256x256 pixel image of the whole earth. A 256x256 tile for zoom level 1 enlarges a 128x128 pixel region from zoom level 0.

As correctly stated by bkaid, the available zoom range depends on where you are looking and the kind of map you are using:

  • Road maps - seem to go up to zoom level 22 everywhere
  • Hybrid and satellite maps - the max available zoom levels depend on location. Here are some examples:
  • Remote regions of Antarctica: 13
  • Gobi Desert: 17
  • Much of the U.S. and Europe: 21
  • "Deep zoom" locations: 22-23 (see bkaid's link)

Note that these values are for the Google Static Maps API which seems to give one more zoom level than the Javascript API. It appears that the extra zoom level available for Static Maps is just an upsampled version of the max-resolution image from the Javascript API.

Map Scale at Various Zoom Levels

Google Maps uses a Mercator projection so the scale varies substantially with latitude. A formula for calculating the correct scale based on latitude is:

meters_per_pixel = 156543.03392 * Math.cos(latLng.lat() * Math.PI / 180) / Math.pow(2, zoom)

Formula is from Chris Broadfoot's comment.


Google Maps basics

Zoom Level - zoom

0 - 19

0 lowest zoom (whole world)

19 highest zoom (individual buildings, if available) Retrieve current zoom level using mapObject.getZoom()


What you're looking for are the scales for each zoom level. Use these:

20 : 1128.497220
19 : 2256.994440
18 : 4513.988880
17 : 9027.977761
16 : 18055.955520
15 : 36111.911040
14 : 72223.822090
13 : 144447.644200
12 : 288895.288400
11 : 577790.576700
10 : 1155581.153000
9  : 2311162.307000
8  : 4622324.614000
7  : 9244649.227000
6  : 18489298.450000
5  : 36978596.910000
4  : 73957193.820000
3  : 147914387.600000
2  : 295828775.300000
1  : 591657550.500000

Java check to see if a variable has been initialized

Assuming you're interested in whether the variable has been explicitly assigned a value or not, the answer is "not really". There's absolutely no difference between a field (instance variable or class variable) which hasn't been explicitly assigned at all yet, and one which has been assigned its default value - 0, false, null etc.

Now if you know that once assigned, the value will never reassigned a value of null, you can use:

if (box != null) {
    box.removeFromCanvas();
}

(and that also avoids a possible NullPointerException) but you need to be aware that "a field with a value of null" isn't the same as "a field which hasn't been explicitly assigned a value". Null is a perfectly valid variable value (for non-primitive variables, of course). Indeed, you may even want to change the above code to:

if (box != null) {
    box.removeFromCanvas();
    // Forget about the box - we don't want to try to remove it again
    box = null;
}

The difference is also visible for local variables, which can't be read before they've been "definitely assigned" - but one of the values which they can be definitely assigned is null (for reference type variables):

// Won't compile
String x;
System.out.println(x);

// Will compile, prints null
String y = null;
System.out.println(y);

Access props inside quotes in React JSX

you can use

<img className="image" src=`images/${this.props.image}`>

or

<img className="image" src={'images/'+this.props.image}>

or

  render() {
         let imageUrl = this.props.image ? "images/"+this.props.image : 'some placeholder url image';
    return (
       <div>
          <img className="image" src={imageUrl} />
       </div>
    )
  }

How to get config parameters in Symfony2 Twig Templates

In confing.yml

# app/config/config.yml
twig:
  globals:
    version: '%app.version%'

In Twig view

# twig view
{{ version }}

Quick-and-dirty way to ensure only one instance of a shell script is running at a time

For shell scripts, I tend to go with the mkdir over flock as it makes the locks more portable.

Either way, using set -e isn't enough. That only exits the script if any command fails. Your locks will still be left behind.

For proper lock cleanup, you really should set your traps to something like this psuedo code (lifted, simplified and untested but from actively used scripts) :

#=======================================================================
# Predefined Global Variables
#=======================================================================

TMPDIR=/tmp/myapp
[[ ! -d $TMP_DIR ]] \
    && mkdir -p $TMP_DIR \
    && chmod 700 $TMPDIR

LOCK_DIR=$TMP_DIR/lock

#=======================================================================
# Functions
#=======================================================================

function mklock {
    __lockdir="$LOCK_DIR/$(date +%s.%N).$$" # Private Global. Use Epoch.Nano.PID

    # If it can create $LOCK_DIR then no other instance is running
    if $(mkdir $LOCK_DIR)
    then
        mkdir $__lockdir  # create this instance's specific lock in queue
        LOCK_EXISTS=true  # Global
    else
        echo "FATAL: Lock already exists. Another copy is running or manually lock clean up required."
        exit 1001  # Or work out some sleep_while_execution_lock elsewhere
    fi
}

function rmlock {
    [[ ! -d $__lockdir ]] \
        && echo "WARNING: Lock is missing. $__lockdir does not exist" \
        || rmdir $__lockdir
}

#-----------------------------------------------------------------------
# Private Signal Traps Functions {{{2
#
# DANGER: SIGKILL cannot be trapped. So, try not to `kill -9 PID` or 
#         there will be *NO CLEAN UP*. You'll have to manually remove 
#         any locks in place.
#-----------------------------------------------------------------------
function __sig_exit {

    # Place your clean up logic here 

    # Remove the LOCK
    [[ -n $LOCK_EXISTS ]] && rmlock
}

function __sig_int {
    echo "WARNING: SIGINT caught"    
    exit 1002
}

function __sig_quit {
    echo "SIGQUIT caught"
    exit 1003
}

function __sig_term {
    echo "WARNING: SIGTERM caught"    
    exit 1015
}

#=======================================================================
# Main
#=======================================================================

# Set TRAPs
trap __sig_exit EXIT    # SIGEXIT
trap __sig_int INT      # SIGINT
trap __sig_quit QUIT    # SIGQUIT
trap __sig_term TERM    # SIGTERM

mklock

# CODE

exit # No need for cleanup code here being in the __sig_exit trap function

Here's what will happen. All traps will produce an exit so the function __sig_exit will always happen (barring a SIGKILL) which cleans up your locks.

Note: my exit values are not low values. Why? Various batch processing systems make or have expectations of the numbers 0 through 31. Setting them to something else, I can have my scripts and batch streams react accordingly to the previous batch job or script.

How to check the gradle version in Android Studio?

You can install andle for gradle version management.

It can help you sync to the latest version almost everything in gradle file.

Simple three step to update all project at once.

1. install:

    $ sudo pip install andle

2. set sdk:

    $ andle setsdk -p <sdk_path>

3. update depedency:

    $ andle update -p <project_path> [--dryrun] [--remote] [--gradle]

--dryrun: only print result in console

--remote: check version in jcenter and mavenCentral

--gradle: check gradle version

See https://github.com/Jintin/andle for more information

Update data on a page without refreshing

Suppose you want to display some live feed content (say livefeed.txt) on you web page without any page refresh then the following simplified example is for you.

In the below html file, the live data gets updated on the div element of id "liveData"

index.html

<!DOCTYPE html>
<html>
<head>
    <title>Live Update</title>
    <meta charset="UTF-8">
    <script type="text/javascript" src="autoUpdate.js"></script>
</head>
<div id="liveData">
    <p>Loading Data...</p>
</div>
</body>
</html>

Below autoUpdate.js reads the live data using XMLHttpRequest object and updates the html div element on every 1 second. I have given comments on most part of the code for better understanding.

autoUpdate.js

window.addEventListener('load', function()
{
    var xhr = null;

    getXmlHttpRequestObject = function()
    {
        if(!xhr)
        {               
            // Create a new XMLHttpRequest object 
            xhr = new XMLHttpRequest();
        }
        return xhr;
    };

    updateLiveData = function()
    {
        var now = new Date();
        // Date string is appended as a query with live data 
        // for not to use the cached version 
        var url = 'livefeed.txt?' + now.getTime();
        xhr = getXmlHttpRequestObject();
        xhr.onreadystatechange = evenHandler;
        // asynchronous requests
        xhr.open("GET", url, true);
        // Send the request over the network
        xhr.send(null);
    };

    updateLiveData();

    function evenHandler()
    {
        // Check response is ready or not
        if(xhr.readyState == 4 && xhr.status == 200)
        {
            dataDiv = document.getElementById('liveData');
            // Set current data text
            dataDiv.innerHTML = xhr.responseText;
            // Update the live data every 1 sec
            setTimeout(updateLiveData(), 1000);
        }
    }
});

For testing purpose: Just write some thing in the livefeed.txt - You will get updated the same in index.html without any refresh.

livefeed.txt

Hello
World
blah..
blah..

Note: You need to run the above code on the web server (ex: http://localhost:1234/index.html) not as a client html file (ex: file:///C:/index.html).

Difference in days between two dates in Java?

You say it "works fine in a standalone program," but that you get "unusual difference values" when you "include this into my logic to read from report". That suggests that your report has some values for which it doesn't work correctly, and your standalone program doesn't have those values. Instead of a standalone program, I suggest a test case. Write a test case much as you would a standalone program, subclassing from JUnit's TestCase class. Now you can run a very specific example, knowing what value you expect (and don't give it today for the test value, because today changes over time). If you put in the values you used in the standalone program, your tests will probably pass. That's great - you want those cases to keep working. Now, add a value from your report, one that doesn't work right. Your new test will probably fail. Figure out why it's failing, fix it, and get to green (all tests passing). Run your report. See what's still broken; write a test; make it pass. Pretty soon you'll find your report is working.

How do I format date in jQuery datetimepicker?

Newer versions of datetimepicker (I'm using is use 2.3.7) use format:"Y/m/d" not dateFormat...

so

jQuery('#timePicker').datetimepicker({
    format: 'd-m-y',
    value: new Date()
});

See http://xdsoft.net/jqplugins/datetimepicker/

Insert variable into Header Location PHP

There's nothing here explaining the use of multiple variables, so I'll chuck it in just incase someone needs it in the future.

You need to concatenate multiple variables:

header('Location: http://linkhere.com?var1='.$var1.'&var2='.$var2.'&var3'.$var3);

How do I deal with certificates using cURL while trying to access an HTTPS url?

Another alternative to fix this problem is to disable the certificate validation:

echo insecure >> ~/.curlrc

How do CSS triangles work?

OK, this triangle will get created because of the way that borders of the elements work together in HTML and CSS...

As we usually use 1 or 2px borders, we never notice that borders make a 45° angles to each others with the same width and if the width changes, the angle degree get changed as well, run the CSS code I created below:

_x000D_
_x000D_
.triangle {_x000D_
  width: 100px;_x000D_
  height: 100px;_x000D_
  border-left: 50px solid black;_x000D_
  border-right: 50px solid black;_x000D_
  border-bottom: 100px solid red;_x000D_
}
_x000D_
<div class="triangle">_x000D_
</div>
_x000D_
_x000D_
_x000D_

Then in the next step, we don't have any width or height, something like this:

_x000D_
_x000D_
.triangle {_x000D_
  width: 0;_x000D_
  height: 0;_x000D_
  border-left: 50px solid black;_x000D_
  border-right: 50px solid black;_x000D_
  border-bottom: 100px solid red;_x000D_
}
_x000D_
<div class="triangle">_x000D_
</div>
_x000D_
_x000D_
_x000D_

And now we make the left and right borders invisible to make our desirable triangle as below:

_x000D_
_x000D_
.triangle {_x000D_
  width: 0;_x000D_
  height: 0;_x000D_
  border-left: 50px solid transparent;_x000D_
  border-right: 50px solid transparent;_x000D_
  border-bottom: 100px solid red;_x000D_
}
_x000D_
<div class="triangle"></div>
_x000D_
_x000D_
_x000D_

If you not willing to run the snippet to see the steps, I've created an image sequence to have a look at all steps in one image:

enter image description here

How to force the input date format to dd/mm/yyyy?

DEMO : http://jsfiddle.net/shfj70qp/

//dd/mm/yyyy 

var date = new Date();
var month = date.getMonth();
var day = date.getDate();
var year = date.getFullYear();

console.log(month+"/"+day+"/"+year);

clear data inside text file in c++

Deleting the file will also remove the content. See remove file.

How do you know a variable type in java?

I agree with what Joachim Sauer said, not possible to know (the variable type! not value type!) unless your variable is a class attribute (and you would have to retrieve class fields, get the right field by name...)

Actually for me it's totally impossible that any a.xxx().yyy() method give you the right answer since the answer would be different on the exact same object, according to the context in which you call this method...

As teehoo said, if you know at compile a defined list of types to test you can use instanceof but you will also get subclasses returning true...

One possible solution would also be to inspire yourself from the implementation of java.lang.reflect.Field and create your own Field class, and then declare all your local variables as this custom Field implementation... but you'd better find another solution, i really wonder why you need the variable type, and not just the value type?

What does $(function() {} ); do?

It's just shorthand for $(document).ready(), as in: $(document).ready(function() { YOUR_CODE_HERE });. Sometimes you have to use it because your function is running before the DOM finishes loading.

Everything is explained here: http://docs.jquery.com/Tutorials:Introducing_$(document).ready()

select count(*) from select

You're missing a FROM and you need to give the subquery an alias.

SELECT COUNT(*) FROM 
(
  SELECT DISTINCT a.my_id, a.last_name, a.first_name, b.temp_val
   FROM dbo.Table_A AS a 
   INNER JOIN dbo.Table_B AS b 
   ON a.a_id = b.a_id
) AS subquery;

How to do a SUM() inside a case statement in SQL server

If you're using SQL Server 2005 or above, you can use the windowing function SUM() OVER ().

case 
when test1.TotalType = 'Average' then Test2.avgscore
when test1.TotalType = 'PercentOfTot' then (cnt/SUM(test1.qrank) over ())
else cnt
end as displayscore

But it'll be better if you show your full query to get context of what you actually need.

for loop in Python

You should also know that in Python, iterating over integer indices is bad style, and also slower than the alternative. If you just want to look at each of the items in a list or dict, loop directly through the list or dict.

mylist = [1,2,3]
for item in mylist:
    print item

mydict  = {1:'one', 2:'two', 3:'three'}
for key in mydict:
    print key, mydict[key]

This is actually faster than using the above code with range(), and removes the extraneous i variable.

If you need to edit items of a list in-place, then you do need the index, but there's still a better way:

for i, item in enumerate(mylist):
    mylist[i] = item**2

Again, this is both faster and considered more readable. This one of the main shifts in thinking you need to make when coming from C++ to Python.

Arithmetic overflow error converting numeric to data type numeric

My guess is that you're trying to squeeze a number greater than 99999.99 into your decimal fields. Changing it to (8,3) isn't going to do anything if it's greater than 99999.999 - you need to increase the number of digits before the decimal. You can do this by increasing the precision (which is the total number of digits before and after the decimal). You can leave the scale the same unless you need to alter how many decimal places to store. Try decimal(9,2) or decimal(10,2) or whatever.

You can test this by commenting out the insert #temp and see what numbers the select statement is giving you and see if they are bigger than your column can handle.

Getting output of system() calls in Ruby

As a direct system(...) replacement you may use Open3.popen3(...)

Further discussion: http://tech.natemurray.com/2007/03/ruby-shell-commands.html

Adding a color background and border radius to a Layout

background.xml in drawable folder.

<?xml version="1.0" encoding="UTF-8"?> 
<shape xmlns:android="http://schemas.android.com/apk/res/android"> 
    <solid android:color="#FFFFFF"/>    
    <stroke
        android:width="3dp"
        android:color="#0FECFF" />

    //specify gradient
    <gradient
        android:startColor="#ffffffff" 
        android:endColor="#110000FF" 
        android:angle="90"/> 

    <padding
        android:left="5dp"
        android:top="5dp"
        android:right="5dp"
        android:bottom="5dp"/> 
    <corners
        android:bottomRightRadius="7dp"
        android:bottomLeftRadius="7dp" 
        android:topLeftRadius="7dp"
        android:topRightRadius="7dp"/> 
</shape>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="210dp"
    android:orientation="vertical"
    android:layout_marginBottom="10dp"        
    android:background="@drawable/background">

How to enable and use HTTP PUT and DELETE with Apache2 and PHP?

IIRC the purpose of the form method attribute was to define different transport methods. Consequently, HTML 5.2 only defines GET, POST, and DIALOG methods for transport and dialog action, not how the server should process the data.

Ruby-on-rails solves this problem by using POST/GET for everything and adding a hidden form variable that defines the actual ReST method. This approach is more clumsy and error-prone, but does remove the burden from both the HTML standard and browser developers.

The form method was defined before ReST, so you cannot define ReST in HTML, even after enabling Apache and PHP because the browsers conform to HTML and therefore default to GET/POST for all non-HTML defined values. That means, when you send a form to the browser with a PUT method, the browser changes that to GET and uses that instead. The hidden variable, however, passes through everything unchanged, so you can use that to customise your form handling process.

Hope that helps

Syntax error "syntax error, unexpected end-of-input, expecting keyword_end (SyntaxError)"

$ rails server -b $IP -p $PORT - that solved the same problem for me

multiple axis in matplotlib with different scales

Bootstrapping something fast to chart multiple y-axes sharing an x-axis using @joe-kington's answer: enter image description here

# d = Pandas Dataframe, 
# ys = [ [cols in the same y], [cols in the same y], [cols in the same y], .. ] 
def chart(d,ys):

    from itertools import cycle
    fig, ax = plt.subplots()

    axes = [ax]
    for y in ys[1:]:
        # Twin the x-axis twice to make independent y-axes.
        axes.append(ax.twinx())

    extra_ys =  len(axes[2:])

    # Make some space on the right side for the extra y-axes.
    if extra_ys>0:
        temp = 0.85
        if extra_ys<=2:
            temp = 0.75
        elif extra_ys<=4:
            temp = 0.6
        if extra_ys>5:
            print 'you are being ridiculous'
        fig.subplots_adjust(right=temp)
        right_additive = (0.98-temp)/float(extra_ys)
    # Move the last y-axis spine over to the right by x% of the width of the axes
    i = 1.
    for ax in axes[2:]:
        ax.spines['right'].set_position(('axes', 1.+right_additive*i))
        ax.set_frame_on(True)
        ax.patch.set_visible(False)
        ax.yaxis.set_major_formatter(matplotlib.ticker.OldScalarFormatter())
        i +=1.
    # To make the border of the right-most axis visible, we need to turn the frame
    # on. This hides the other plots, however, so we need to turn its fill off.

    cols = []
    lines = []
    line_styles = cycle(['-','-','-', '--', '-.', ':', '.', ',', 'o', 'v', '^', '<', '>',
               '1', '2', '3', '4', 's', 'p', '*', 'h', 'H', '+', 'x', 'D', 'd', '|', '_'])
    colors = cycle(matplotlib.rcParams['axes.color_cycle'])
    for ax,y in zip(axes,ys):
        ls=line_styles.next()
        if len(y)==1:
            col = y[0]
            cols.append(col)
            color = colors.next()
            lines.append(ax.plot(d[col],linestyle =ls,label = col,color=color))
            ax.set_ylabel(col,color=color)
            #ax.tick_params(axis='y', colors=color)
            ax.spines['right'].set_color(color)
        else:
            for col in y:
                color = colors.next()
                lines.append(ax.plot(d[col],linestyle =ls,label = col,color=color))
                cols.append(col)
            ax.set_ylabel(', '.join(y))
            #ax.tick_params(axis='y')
    axes[0].set_xlabel(d.index.name)
    lns = lines[0]
    for l in lines[1:]:
        lns +=l
    labs = [l.get_label() for l in lns]
    axes[0].legend(lns, labs, loc=0)

    plt.show()

how to prevent this error : Warning: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given in ... on line 11

If you just want to suppress warnings from a function, you can add an @ sign in front:

<?php @function_that_i_dont_want_to_see_errors_from(parameters); ?>

Equivalent of waitForVisible/waitForElementPresent in Selenium WebDriver tests using Java?

Implicit and Explicit Waits

Implicit Wait

An implicit wait is to tell WebDriver to poll the DOM for a certain amount of time when trying to find an element or elements if they are not immediately available. The default setting is 0. Once set, the implicit wait is set for the life of the WebDriver object instance.

driver.manage().timeouts().implicitlyWait(10, TimeUnit.SECONDS);

Explicit Wait + Expected Conditions

An explicit waits is code you define to wait for a certain condition to occur before proceeding further in the code. The worst case of this is Thread.sleep(), which sets the condition to an exact time period to wait. There are some convenience methods provided that help you write code that will wait only as long as required. WebDriverWait in combination with ExpectedCondition is one way this can be accomplished.

WebDriverWait wait = new WebDriverWait(driver, 10);
WebElement element = wait.until(
        ExpectedConditions.visibilityOfElementLocated(By.id("someid")));

How do I make a fully statically linked .exe with Visual Studio Express 2005?

My experience in Visual Studio 2010 is that there are two changes needed so as to not need DLL's. From the project property page (right click on the project name in the Solution Explorer window):

  1. Under Configuration Properties --> General, change the "Use of MFC" field to "Use MFC in a Static Library".

  2. Under Configuration Properties --> C/C++ --> Code Generation, change the "Runtime Library" field to "Multi-Threaded (/MT)"

Not sure why both were needed. I used this to remove a dependency on glut32.dll.

Added later: When making these changes to the configurations, you should make them to "All Configurations" --- you can select this at the top of the Properties window. If you make the change to just the Debug configuration, it won't apply to the Release configuration, and vice-versa.

Case objects vs Enumerations in Scala

UPDATE: A new macro based solution has been created which is far superior to the solution I outline below. I strongly recommend using this new macro based solution. And it appears plans for Dotty will make this style of enum solution part of the language. Whoohoo!

Summary:
There are three basic patterns for attempting to reproduce the Java Enum within a Scala project. Two of the three patterns; directly using Java Enum and scala.Enumeration, are not capable of enabling Scala's exhaustive pattern matching. And the third one; "sealed trait + case object", does...but has JVM class/object initialization complications resulting in inconsistent ordinal index generation.

I have created a solution with two classes; Enumeration and EnumerationDecorated, located in this Gist. I didn't post the code into this thread as the file for Enumeration was quite large (+400 lines - contains lots of comments explaining implementation context).

Details:
The question you're asking is pretty general; "...when to use caseclassesobjects vs extending [scala.]Enumeration". And it turns out there are MANY possible answers, each answer depending on the subtleties of the specific project requirements you have. The answer can be reduced down to three basic patterns.

To start, let's make sure we are working from the same basic idea of what an enumeration is. Let's define an enumeration mostly in terms of the Enum provided as of Java 5 (1.5):

  1. It contains a naturally ordered closed set of named members
    1. There is a fixed number of members
    2. Members are naturally ordered and explicitly indexed
      • As opposed to being sorted based on some inate member queriable criteria
    3. Each member has a unique name within the total set of all members
  2. All members can easily be iterated through based on their indexes
  3. A member can be retrieved with its (case sensitive) name
    1. It would be quite nice if a member could also be retrieved with its case insensitive name
  4. A member can be retrieved with its index
  5. Members may easily, transparently and efficiently use serialization
  6. Members may be easily extended to hold additional associated singleton-ness data
  7. Thinking beyond Java's Enum, it would be nice to be able to explicitly leverage Scala's pattern matching exhaustiveness checking for an enumeration

Next, let's look at boiled down versions of the three most common solution patterns posted:

A) Actually directly using Java Enum pattern (in a mixed Scala/Java project):

public enum ChessPiece {
    KING('K', 0)
  , QUEEN('Q', 9)
  , BISHOP('B', 3)
  , KNIGHT('N', 3)
  , ROOK('R', 5)
  , PAWN('P', 1)
  ;

  private char character;
  private int pointValue;

  private ChessPiece(char character, int pointValue) {
    this.character = character; 
    this.pointValue = pointValue;   
  }

  public int getCharacter() {
    return character;
  }

  public int getPointValue() {
    return pointValue;
  }
}

The following items from the enumeration definition are not available:

  1. 3.1 - It would be quite nice if a member could also be retrieved with its case insensitive name
  2. 7 - Thinking beyond Java's Enum, it would be nice to be able to explicitly leverage Scala's pattern matching exhaustiveness checking for an enumeration

For my current projects, I don't have the benefit of taking the risks around the Scala/Java mixed project pathway. And even if I could choose to do a mixed project, item 7 is critical for allowing me to catch compile time issues if/when I either add/remove enumeration members, or am writing some new code to deal with existing enumeration members.


B) Using the "sealed trait + case objects" pattern:

sealed trait ChessPiece {def character: Char; def pointValue: Int}
object ChessPiece {
  case object KING extends ChessPiece {val character = 'K'; val pointValue = 0}
  case object QUEEN extends ChessPiece {val character = 'Q'; val pointValue = 9}
  case object BISHOP extends ChessPiece {val character = 'B'; val pointValue = 3}
  case object KNIGHT extends ChessPiece {val character = 'N'; val pointValue = 3}
  case object ROOK extends ChessPiece {val character = 'R'; val pointValue = 5}
  case object PAWN extends ChessPiece {val character = 'P'; val pointValue = 1}
}

The following items from the enumeration definition are not available:

  1. 1.2 - Members are naturally ordered and explicitly indexed
  2. 2 - All members can easily be iterated through based on their indexes
  3. 3 - A member can be retrieved with its (case sensitive) name
  4. 3.1 - It would be quite nice if a member could also be retrieved with its case insensitive name
  5. 4 - A member can be retrieved with its index

It's arguable it really meets enumeration definition items 5 and 6. For 5, it's a stretch to claim it's efficient. For 6, it's not really easy to extend to hold additional associated singleton-ness data.


C) Using the scala.Enumeration pattern (inspired by this StackOverflow answer):

object ChessPiece extends Enumeration {
  val KING = ChessPieceVal('K', 0)
  val QUEEN = ChessPieceVal('Q', 9)
  val BISHOP = ChessPieceVal('B', 3)
  val KNIGHT = ChessPieceVal('N', 3)
  val ROOK = ChessPieceVal('R', 5)
  val PAWN = ChessPieceVal('P', 1)
  protected case class ChessPieceVal(character: Char, pointValue: Int) extends super.Val()
  implicit def convert(value: Value) = value.asInstanceOf[ChessPieceVal]
}

The following items from the enumeration definition are not available (happens to be identical to the list for directly using the Java Enum):

  1. 3.1 - It would be quite nice if a member could also be retrieved with its case insensitive name
  2. 7 - Thinking beyond Java's Enum, it would be nice to be able to explicitly leverage Scala's pattern matching exhaustiveness checking for an enumeration

Again for my current projects, item 7 is critical for allowing me to catch compile time issues if/when I either add/remove enumeration members, or am writing some new code to deal with existing enumeration members.


So, given the above definition of an enumeration, none of the above three solutions work as they do not provide everything outlined in the enumeration definition above:

  1. Java Enum directly in a mixed Scala/Java project
  2. "sealed trait + case objects"
  3. scala.Enumeration

Each of these solutions can be eventually reworked/expanded/refactored to attempt to cover some of each one's missing requirements. However, neither the Java Enum nor the scala.Enumeration solutions can be sufficiently expanded to provide item 7. And for my own projects, this is one of the more compelling values of using a closed type within Scala. I strongly prefer compile time warnings/errors to indicate I have a gap/issue in my code as opposed to having to glean it out of a production runtime exception/failure.


In that regard, I set about working with the case object pathway to see if I could produce a solution which covered all of the enumeration definition above. The first challenge was to push through the core of the JVM class/object initialization issue (covered in detail in this StackOverflow post). And I was finally able to figure out a solution.

As my solution is two traits; Enumeration and EnumerationDecorated, and since the Enumeration trait is over +400 lines long (lots of comments explaining context), I am forgoing pasting it into this thread (which would make it stretch down the page considerbly). For details, please jump directly to the Gist.

Here's what the solution ends up looking like using the same data idea as above (fully commented version available here) and implemented in EnumerationDecorated.

import scala.reflect.runtime.universe.{TypeTag,typeTag}
import org.public_domain.scala.utils.EnumerationDecorated

object ChessPiecesEnhancedDecorated extends EnumerationDecorated {
  case object KING extends Member
  case object QUEEN extends Member
  case object BISHOP extends Member
  case object KNIGHT extends Member
  case object ROOK extends Member
  case object PAWN extends Member

  val decorationOrderedSet: List[Decoration] =
    List(
        Decoration(KING,   'K', 0)
      , Decoration(QUEEN,  'Q', 9)
      , Decoration(BISHOP, 'B', 3)
      , Decoration(KNIGHT, 'N', 3)
      , Decoration(ROOK,   'R', 5)
      , Decoration(PAWN,   'P', 1)
    )

  final case class Decoration private[ChessPiecesEnhancedDecorated] (member: Member, char: Char, pointValue: Int) extends DecorationBase {
    val description: String = member.name.toLowerCase.capitalize
  }
  override def typeTagMember: TypeTag[_] = typeTag[Member]
  sealed trait Member extends MemberDecorated
}

This is an example usage of a new pair of enumeration traits I created (located in this Gist) to implement all of the capabilities desired and outlined in the enumeration definition.

One concern expressed is that the enumeration member names must be repeated (decorationOrderedSet in the example above). While I did minimize it down to a single repetition, I couldn't see how to make it even less due to two issues:

  1. JVM object/class initialization for this particular object/case object model is undefined (see this Stackoverflow thread)
  2. The content returned from the method getClass.getDeclaredClasses has an undefined order (and it is quite unlikely to be in the same order as the case object declarations in the source code)

Given these two issues, I had to give up trying to generate an implied ordering and had to explicitly require the client define and declare it with some sort of ordered set notion. As the Scala collections do not have an insert ordered set implementation, the best I could do was use a List and then runtime check that it was truly a set. It's not how I would have preferred to have achieved this.

And given the design required this second list/set ordering val, given the ChessPiecesEnhancedDecorated example above, it was possible to add case object PAWN2 extends Member and then forget to add Decoration(PAWN2,'P2', 2) to decorationOrderedSet. So, there is a runtime check to verify that the list is not only a set, but contains ALL of the case objects which extend the sealed trait Member. That was a special form of reflection/macro hell to work through.


Please leave comments and/or feedback on the Gist.

How to install mscomct2.ocx file from .cab file (Excel User Form and VBA)

You're correct that this is really painful to hand out to others, but if you have to, this is how you do it.

  1. Just extract the .ocx file from the .cab file (it is similar to a zip)
  2. Copy to the system folder (c:\windows\sysWOW64 for 64 bit systems and c:\windows\system32 for 32 bit)
  3. Use regsvr32 through the command prompt to register the file (e.g. "regsvr32 c:\windows\sysWOW64\mscomct2.ocx")

References

gdb: "No symbol table is loaded"

I met this issue this morning because I used the same executable in DIFFERENT OSes: after compiling my program with gcc -ggdb -Wall test.c -o test in my Mac(10.15.2), I ran gdb with the executable in Ubuntu(16.04) in my VirtualBox.

Fix: recompile with the same command under Ubuntu, then you should be good.

Rebase array keys after unsetting elements

100% working for me ! After unset elements in array you can use this for re-indexing the array

$result=array_combine(range(1, count($your_array)), array_values($your_array));

How to set enum to null

I'm assuming c++ here. If you're using c#, the answer is probably the same, but the syntax will be a bit different. The enum is a set of int values. It's not an object, so you shouldn't be setting it to null. Setting something to null means you are pointing a pointer to an object to address zero. You can't really do that with an int. What you want to do with an int is to set it to a value you wouldn't normally have it at so that you can tel if it's a good value or not. So, set your colour to -1

Color color = -1;

Or, you can start your enum at 1 and set it to zero. If you set the colour to zero as it is right now, you will be setting it to "red" because red is zero in your enum.

So,

enum Color {
red =1
blue,
green
}
//red is 1, blue is 2, green is 3
Color mycolour = 0;

Force hide address bar in Chrome on Android

window.scrollTo(0,1);

this will help you but this javascript is may not work in all browsers

error: ORA-65096: invalid common user or role name in oracle

Create user dependency upon the database connect tools

sql plus
SQL> connect as sysdba;
Enter user-name: sysdba
Enter password:
Connected.
SQL> ALTER USER hr account unlock identified by hr;
User altered
 then create user on sql plus and sql developer

What does ${} (dollar sign and curly braces) mean in a string in Javascript?

You're talking about template literals.

They allow for both multiline strings and string interpolation.

Multiline strings:

_x000D_
_x000D_
console.log(`foo_x000D_
bar`);_x000D_
// foo_x000D_
// bar
_x000D_
_x000D_
_x000D_

String interpolation:

_x000D_
_x000D_
var foo = 'bar';_x000D_
console.log(`Let's meet at the ${foo}`);_x000D_
// Let's meet at the bar
_x000D_
_x000D_
_x000D_

How to use curl in a shell script?

Firstly, your example is looking quite correct and works well on my machine. You may go another way.

curl $CURLARGS $RVMHTTP > ./install.sh

All output now storing in ./install.sh file, which you can edit and execute.

Iterating over dictionaries using 'for' loops

You can check the implementation of CPython's dicttype on GitHub. This is the signature of method that implements the dict iterator:

_PyDict_Next(PyObject *op, Py_ssize_t *ppos, PyObject **pkey,
             PyObject **pvalue, Py_hash_t *phash)

CPython dictobject.c

Determine if map contains a value for a key?

Does something along these lines exist?

No. With the stl map class, you use ::find() to search the map, and compare the returned iterator to std::map::end()

so

map<int,Bar>::iterator it = m.find('2');
Bar b3;
if(it != m.end())
{
   //element found;
   b3 = it->second;
}

Obviously you can write your own getValue() routine if you want (also in C++, there is no reason to use out), but I would suspect that once you get the hang of using std::map::find() you won't want to waste your time.

Also your code is slightly wrong:

m.find('2'); will search the map for a keyvalue that is '2'. IIRC the C++ compiler will implicitly convert '2' to an int, which results in the numeric value for the ASCII code for '2' which is not what you want.

Since your keytype in this example is int you want to search like this: m.find(2);

C: convert double to float, preserving decimal point precision

Floating point numbers are represented in scientific notation as a number of only seven significant digits multiplied by a larger number that represents the place of the decimal place. More information about it on Wikipedia:

http://en.wikipedia.org/wiki/Floating_point

How to use ScrollView in Android?

Put your TableLayout inside a ScrollView Layout.That will solve your problem.

Where's my JSON data in my incoming Django request?

request.raw_post_data has been deprecated. Use request.body instead

Upgrading Node.js to latest version

sudo npm install n -g sudo n 0.12.2

or

sudo npm install -g n sudo n latest

or

sudo npm cache clean -f sudo npm install -g n sudo n latest

These work well. But for UX term terminal node -v did not show latest version so I have closed and reopened new terminal. I found v10.1.0, output of node-v after installation by sudo n latest

python replace single backslash with double backslash

Use:

string.replace(r"C:\Users\Josh\Desktop\20130216", "\\", "\\")

Escape the \ character.

Check if a row exists using old mysql_* API

If you just want to compare only one row with $lactureName then use following

function checkLectureStatus($lectureName)
{
 $con = connectvar();
 mysql_select_db("mydatabase", $con);
 $result = mysql_query("SELECT * FROM preditors_assigned WHERE lecture_name='$lectureName'");
  if(mysql_num_rows($result) > 0)
  {
         mysql_close($con);
         return "Assigned";
  }
  else
  {
        mysql_close($con);
        return "Available";
  }
}

Is a Python list guaranteed to have its elements stay in the order they are inserted in?

In short, yes, the order is preserved. In long:

In general the following definitions will always apply to objects like lists:

A list is a collection of elements that can contain duplicate elements and has a defined order that generally does not change unless explicitly made to do so. stacks and queues are both types of lists that provide specific (often limited) behavior for adding and removing elements (stacks being LIFO, queues being FIFO). Lists are practical representations of, well, lists of things. A string can be thought of as a list of characters, as the order is important ("abc" != "bca") and duplicates in the content of the string are certainly permitted ("aaa" can exist and != "a").

A set is a collection of elements that cannot contain duplicates and has a non-definite order that may or may not change over time. Sets do not represent lists of things so much as they describe the extent of a certain selection of things. The internal structure of set, how its elements are stored relative to each other, is usually not meant to convey useful information. In some implementations, sets are always internally sorted; in others the ordering is simply undefined (usually depending on a hash function).

Collection is a generic term referring to any object used to store a (usually variable) number of other objects. Both lists and sets are a type of collection. Tuples and Arrays are normally not considered to be collections. Some languages consider maps (containers that describe associations between different objects) to be a type of collection as well.

This naming scheme holds true for all programming languages that I know of, including Python, C++, Java, C#, and Lisp (in which lists not keeping their order would be particularly catastrophic). If anyone knows of any where this is not the case, please just say so and I'll edit my answer. Note that specific implementations may use other names for these objects, such as vector in C++ and flex in ALGOL 68 (both lists; flex is technically just a re-sizable array).

If there is any confusion left in your case due to the specifics of how the + sign works here, just know that order is important for lists and unless there is very good reason to believe otherwise you can pretty much always safely assume that list operations preserve order. In this case, the + sign behaves much like it does for strings (which are really just lists of characters anyway): it takes the content of a list and places it behind the content of another.

If we have

list1 = [0, 1, 2, 3, 4]
list2 = [5, 6, 7, 8, 9]

Then

list1 + list2

Is the same as

[0, 1, 2, 3, 4] + [5, 6, 7, 8, 9]

Which evaluates to

[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]

Much like

"abdcde" + "fghijk"

Produces

"abdcdefghijk"

What is the meaning of the term "thread-safe"?

In simplest words :P If it is safe to execute multiple threads on a block of code it is thread safe*

*conditions apply

Conditions are mentioned by other answeres like 1. The result should be same if you execute one thread or multiple threads over it etc.

How to get folder directory from HTML input type "file" or any other way?

Eventhough it is an old question, this may help someone.

We can choose multiple files while browsing for a file using "multiple"

<input type="file" name="datafile" size="40"  multiple> 

Server unable to read htaccess file, denying access to be safe

Every public folder makes the permission to 755. Problem solved.

how to make a div to wrap two float divs inside?

Here's another, I found helpful. It works even for Responsive CSS design too.

#wrap
{
   display: table;
   table-layout: fixed; /* it'll enable the div to be responsive */
   width: 100%; /* as display table will shrink the div to content-wide */
}

WARNING: But this theory won't work for holder contains inner elements with absolute positions. And it will create problem for fixed-width layout. But for responsive design, it's just excellent. :)

ADDITION TO Meep3D's ANSWER

With CSS3, in a dynamic portion, you can add clear float to the last element by:

#wrap [class*='my-div-class']:last-of-type {
  display: block;
  clear: both;
}

Where your divs are:

<div id="wrap">
<?php for( $i = 0; $i < 3; $i++ ) {
   <div class="my-div-class-<?php echo $i ?>>
      <p>content</p>
   </div> <!-- .my-div-class-<?php echo $i ?> -->
}
</div>

Reference:

Send data through routing paths in Angular

Best I found on internet for this is ngx-navigation-with-data. It is very simple and good for navigation the data from one component to another component. You have to just import the component class and use it in very simple way. Suppose you have home and about component and want to send data then

HOME COMPONENT

import { Component, OnInit } from '@angular/core';
import { NgxNavigationWithDataComponent } from 'ngx-navigation-with-data';

@Component({
 selector: 'app-home',
 templateUrl: './home.component.html',
 styleUrls: ['./home.component.css']
})
export class HomeComponent implements OnInit {

constructor(public navCtrl: NgxNavigationWithDataComponent) { }

 ngOnInit() {
 }

 navigateToABout() {
  this.navCtrl.navigate('about', {name:"virendta"});
 }

}

ABOUT COMPONENT

import { Component, OnInit } from '@angular/core';
import { NgxNavigationWithDataComponent } from 'ngx-navigation-with-data';

@Component({
 selector: 'app-about',
 templateUrl: './about.component.html',
 styleUrls: ['./about.component.css']
})
export class AboutComponent implements OnInit {

 constructor(public navCtrl: NgxNavigationWithDataComponent) {
  console.log(this.navCtrl.get('name')); // it will console Virendra
  console.log(this.navCtrl.data); // it will console whole data object here
 }

 ngOnInit() {
 }

}

For any query follow https://www.npmjs.com/package/ngx-navigation-with-data

Comment down for help.

How to bind Events on Ajax loaded Content?

if your question is "how to bind events on ajax loaded content" you can do like this :

$("img.lazy").lazyload({
    effect : "fadeIn",
    event: "scrollstop",
    skip_invisible : true
}).removeClass('lazy');

// lazy load to DOMNodeInserted event
$(document).bind('DOMNodeInserted', function(e) {
    $("img.lazy").lazyload({
        effect : "fadeIn",
        event: "scrollstop",
        skip_invisible : true
    }).removeClass('lazy');
});

so you don't need to place your configuration to every you ajax code

Why do we have to normalize the input for an artificial neural network?

It's explained well here.

If the input variables are combined linearly, as in an MLP [multilayer perceptron], then it is rarely strictly necessary to standardize the inputs, at least in theory. The reason is that any rescaling of an input vector can be effectively undone by changing the corresponding weights and biases, leaving you with the exact same outputs as you had before. However, there are a variety of practical reasons why standardizing the inputs can make training faster and reduce the chances of getting stuck in local optima. Also, weight decay and Bayesian estimation can be done more conveniently with standardized inputs.

How can I stop .gitignore from appearing in the list of untracked files?

First of all, as many others already said, your .gitignore should be tracked by Git (and should therefore not be ignored). Let me explain why.

(TL;DR: commit the .gitignore file, and use a global .gitignore to ignore files that are created by your IDE or operating system)

Git is, as you probably already know, a distributed version control system. This means that it allows you to switch back and forth between different versions (even if development has diverged into different branches) and it also allows multiple developers to work on the same project.

Although tracking your .gitignore also has benefits when you switch between snapshots, the most important reason for committing it is that you'll want to share the file with other developers who are working on the same project. By committing the file into Git, other contributers will automatically get the .gitignore file when they clone the repository, so they won't have to worry about accidentally committing a file that shouldn't be committed (such as log files, cache directories, database credentials, etc.). And if at some point the project's .gitignore is updated, they can simply pull in those changes instead of having to edit the file manually.

Of course, there will be some files and folders that you'll want to ignore, but that are specific for you, and don't apply to other developers. However, those should not be in the project's .gitignore. There are two other places where you can ignore files and folders:

  • Files and folders that are created by your operating system or IDE should be placed in a global .gitignore. The benefit is that this .gitignore is applied to all repositories on your computer, so you don't have to repeat this for every repository. And it's not shared with other developers, since they might be using a different operating system and/or IDE.
  • Files that don't belong in the project's .gitignore, nor in the global .gitignore, can be ignored using explicit repository excludes in your_project_directory/.git/info/exclude. This file will not be shared with other developers, and is specific for that single repository

how to add a jpg image in Latex

if you add a jpg,png,pdf picture, you should use pdflatex to compile it.

How to send Basic Auth with axios

If you are trying to do basic auth, you can try this:

const username = ''
const password = ''

const token = Buffer.from(`${username}:${password}`, 'utf8').toString('base64')

const url = 'https://...'
const data = {
...
}

axios.post(url, data, {
  headers: {
 'Authorization': `Basic ${token}`
},
})

This worked for me. Hope that helps

How can I declare optional function parameters in JavaScript?

Update

With ES6, this is possible in exactly the manner you have described; a detailed description can be found in the documentation.

Old answer

Default parameters in JavaScript can be implemented in mainly two ways:

function myfunc(a, b)
{
    // use this if you specifically want to know if b was passed
    if (b === undefined) {
        // b was not passed
    }
    // use this if you know that a truthy value comparison will be enough
    if (b) {
        // b was passed and has truthy value
    } else {
        // b was not passed or has falsy value
    }
    // use this to set b to a default value (using truthy comparison)
    b = b || "default value";
}

The expression b || "default value" evaluates the value AND existence of b and returns the value of "default value" if b either doesn't exist or is falsy.

Alternative declaration:

function myfunc(a)
{
    var b;

    // use this to determine whether b was passed or not
    if (arguments.length == 1) {
        // b was not passed
    } else {
        b = arguments[1]; // take second argument
    }
}

The special "array" arguments is available inside the function; it contains all the arguments, starting from index 0 to N - 1 (where N is the number of arguments passed).

This is typically used to support an unknown number of optional parameters (of the same type); however, stating the expected arguments is preferred!

Further considerations

Although undefined is not writable since ES5, some browsers are known to not enforce this. There are two alternatives you could use if you're worried about this:

b === void 0;
typeof b === 'undefined'; // also works for undeclared variables

How to do a subquery in LINQ?

This is how I've been doing subqueries in LINQ, I think this should get what you want. You can replace the explicit CompanyRoleId == 2... with another subquery for the different roles you want or join it as well.

from u in Users
join c in (
    from crt in CompanyRolesToUsers
    where CompanyRoleId == 2
    || CompanyRoleId == 3
    || CompanyRoleId == 4) on u.UserId equals c.UserId
where u.lastname.Contains("fra")
select u;

How do I connect to a MySQL Database in Python?

Connecting to MYSQL with Python 2 in three steps

1 - Setting

You must install a MySQL driver before doing anything. Unlike PHP, Only the SQLite driver is installed by default with Python. The most used package to do so is MySQLdb but it's hard to install it using easy_install. Please note MySQLdb only supports Python 2.

For Windows user, you can get an exe of MySQLdb.

For Linux, this is a casual package (python-mysqldb). (You can use sudo apt-get install python-mysqldb (for debian based distros), yum install MySQL-python (for rpm-based), or dnf install python-mysql (for modern fedora distro) in command line to download.)

For Mac, you can install MySQLdb using Macport.

2 - Usage

After installing, Reboot. This is not mandatory, But it will prevent me from answering 3 or 4 other questions in this post if something goes wrong. So please reboot.

Then it is just like using any other package :

#!/usr/bin/python
import MySQLdb

db = MySQLdb.connect(host="localhost",    # your host, usually localhost
                     user="john",         # your username
                     passwd="megajonhy",  # your password
                     db="jonhydb")        # name of the data base

# you must create a Cursor object. It will let
#  you execute all the queries you need
cur = db.cursor()

# Use all the SQL you like
cur.execute("SELECT * FROM YOUR_TABLE_NAME")

# print all the first cell of all the rows
for row in cur.fetchall():
    print row[0]

db.close()

Of course, there are thousand of possibilities and options; this is a very basic example. You will have to look at the documentation. A good starting point.

3 - More advanced usage

Once you know how it works, You may want to use an ORM to avoid writing SQL manually and manipulate your tables as they were Python objects. The most famous ORM in the Python community is SQLAlchemy.

I strongly advise you to use it: your life is going to be much easier.

I recently discovered another jewel in the Python world: peewee. It's a very lite ORM, really easy and fast to setup then use. It makes my day for small projects or stand alone apps, Where using big tools like SQLAlchemy or Django is overkill :

import peewee
from peewee import *

db = MySQLDatabase('jonhydb', user='john', passwd='megajonhy')

class Book(peewee.Model):
    author = peewee.CharField()
    title = peewee.TextField()

    class Meta:
        database = db

Book.create_table()
book = Book(author="me", title='Peewee is cool')
book.save()
for book in Book.filter(author="me"):
    print book.title

This example works out of the box. Nothing other than having peewee (pip install peewee) is required.

Programmatically get height of navigation bar

With iPhone-X, height of top bar (navigation bar + status bar) is changed (increased).

Try this if you want exact height of top bar (both navigation bar + status bar):

UPDATE

iOS 13

As the statusBarFrame was deprecated in iOS13 you can use this:

extension UIViewController {

    /**
     *  Height of status bar + navigation bar (if navigation bar exist)
     */

    var topbarHeight: CGFloat {
        return (view.window?.windowScene?.statusBarManager?.statusBarFrame.height ?? 0.0) +
            (self.navigationController?.navigationBar.frame.height ?? 0.0)
    }
}

Objective-C

CGFloat topbarHeight = ([UIApplication sharedApplication].statusBarFrame.size.height +
       (self.navigationController.navigationBar.frame.size.height ?: 0.0));

Swift 4

let topBarHeight = UIApplication.shared.statusBarFrame.size.height +
        (self.navigationController?.navigationBar.frame.height ?? 0.0)

For ease, try this UIViewController extension

extension UIViewController {

    /**
     *  Height of status bar + navigation bar (if navigation bar exist)
     */

    var topbarHeight: CGFloat {
        return UIApplication.shared.statusBarFrame.size.height +
            (self.navigationController?.navigationBar.frame.height ?? 0.0)
    }
}

Swift 3

let topBarHeight = UIApplication.sharedApplication().statusBarFrame.size.height +
(self.navigationController?.navigationBar.frame.height ?? 0.0)

Start a fragment via Intent within a Fragment

You cannot open new fragments. Fragments need to be always hosted by an activity. If the fragment is in the same activity (eg tabs) then the back key navigation is going to be tricky I am assuming that you want to open a new screen with that fragment.

So you would simply create a new activity and put the new fragment in there. That activity would then react to the intent either explicitly via the activity class or implicitly via intent filters.

Ping a site in Python?

using subprocess ping command to ping decode it because the response is binary:

import subprocess
ping_response = subprocess.Popen(["ping", "-a", "google.com"], stdout=subprocess.PIPE).stdout.read()
result = ping_response.decode('utf-8')
print(result)

What is the default root pasword for MySQL 5.7

MySQL 5.7 or newer generates a default temporary password after fresh install.

To use MySQL first you would be required to get that password from the log file which is present at the /var/log/mysqld.log. So follow the following process:

  1. grep 'temporary password' /var/log/mysqld.log

  2. mysql_secure_installation

The second command is required to change the password for MySQL and also to make certain other changes like removing temporary databases, allow or disallow remote access to root user, delete anonymous users etc…

PHP parse/syntax errors; and how to solve them

Unexpected T_IF
Unexpected T_FOREACH
Unexpected T_FOR
Unexpected T_WHILE
Unexpected T_DO
Unexpected T_ECHO

Control constructs such as if, foreach, for, while, list, global, return, do, print, echo may only be used as statements. They usually reside on a line by themselves.

  1. Semicolon; where you at?

    Pretty universally have you missed a semicolon in the previous line if the parser complains about a control statement:

                 ?
    $x = myfunc()
    if (true) {
    

    Solution: look into the previous line; add semicolon.

  2. Class declarations

    Another location where this occurs is in class declarations. In the class section you can only list property initializations and method sections. No code may reside there.

    class xyz {
        if (true) {}
        foreach ($var) {}
    

    Such syntax errors commonly materialize for incorrectly nested { and }. In particular when function code blocks got closed too early.

  3. Statements in expression context

    Most language constructs can only be used as statements. They aren't meant to be placed inside other expressions:

                       ?
    $var = array(1, 2, foreach($else as $_), 5, 6);
    

    Likewise can't you use an if in strings, math expressions or elsewhere:

                   ?
    print "Oh, " . if (true) { "you!" } . " won't work";
    // Use a ternary condition here instead, when versed enough.
    

    For embedding if-like conditions in an expression specifically, you often want to use a ?: ternary evaluation.

    The same applies to for, while, global, echo and a lesser extend list.

              ?
    echo 123, echo 567, "huh?";
    

    Whereas print() is a language built-in that may be used in expression context. (But rarely makes sense.)

  4. Reserved keywords as identifiers

    You also can't use do or if and other language constructs for user-defined functions or class names. (Perhaps in PHP 7. But even then it wouldn't be advisable.)

  5. Your have a semi-colon instead of a colon (:) or curly bracket ({) after your control block

    Control structures are typically wrapped in curly braces (but colons can be used in an alternative syntax) to represent their scope. If you accidentally use a semi-colon you prematurely close that block resulting in your closing statement throwing an error.

    foreach ($errors as $error); <-- should be : or {

Convert an object to an XML string

Here are conversion method for both ways. this = instance of your class

public string ToXML()
    {
        using(var stringwriter = new System.IO.StringWriter())
        { 
            var serializer = new XmlSerializer(this.GetType());
            serializer.Serialize(stringwriter, this);
            return stringwriter.ToString();
        }
    }

 public static YourClass LoadFromXMLString(string xmlText)
    {
        using(var stringReader = new System.IO.StringReader(xmlText))
        {
            var serializer = new XmlSerializer(typeof(YourClass ));
            return serializer.Deserialize(stringReader) as YourClass ;
        }
    }

Make DateTimePicker work as TimePicker only in WinForms

A snippet out of the MSDN:

'The following code sample shows how to create a DateTimePicker that enables users to choose a time only.'

timePicker = new DateTimePicker();
timePicker.Format = DateTimePickerFormat.Time;
timePicker.ShowUpDown = true;

MySQL, Concatenate two columns

$crud->set_relation('id','students','{first_name} {last_name}');
$crud->display_as('student_id','Students Name');

javascript find and remove object in array based on key value

native ES6 solution:

const pos = data.findIndex(el => el.id === ID_TO_REMOVE);
if (pos >= 0)
    data.splice(pos, 1);

if you know that the element is in the array for sure:

data.splice(data.findIndex(el => el.id === ID_TO_REMOVE), 1);

prototype:

Array.prototype.removeByProp = function(prop,val) {
    const pos = this.findIndex(x => x[prop] === val);
    if (pos >= 0)
        return this.splice(pos, 1);
};

// usage:
ar.removeByProp('id', ID_TO_REMOVE);

http://jsfiddle.net/oriadam/72kgprw5/

note: this removes the item in-place. if you need a new array use filter as mentioned in previous answers.

java: use StringBuilder to insert at the beginning

you can use strbuilder.insert(0,i);

Pass mouse events through absolutely-positioned element

The reason you are not receiving the event is because the absolutely positioned element is not a child of the element you are wanting to "click" (blue div). The cleanest way I can think of is to put the absolute element as a child of the one you want clicked, but I'm assuming you can't do that or you wouldn't have posted this question here :)

Another option would be to register a click event handler for the absolute element and call the click handler for the blue div, causing them both to flash.

Due to the way events bubble up through the DOM I'm not sure there is a simpler answer for you, but I'm very curious if anyone else has any tricks I don't know about!

Failed to load AppCompat ActionBar with unknown error in android studio

This is Worked for me i have made the following changes in Style.xml

Change the Following Code:

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

With

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

Entity Framework Core: DbContextOptionsBuilder does not contain a definition for 'usesqlserver' and no extension method 'usesqlserver'

Install below NuGet Package will solve your issue

Microsoft.EntityFrameworkCore.SqlServer

Install-Package Microsoft.EntityFrameworkCore.SqlServer

Press TAB and then ENTER key in Selenium WebDriver

In python this work for me

self.set_your_value = "your value"

def your_method_name(self):      
    self.driver.find_element_by_name(self.set_your_value).send_keys(Keys.TAB)`

Top 5 time-consuming SQL queries in Oracle

the complete information one that I got from askTom-Oracle. I hope it helps you

select * 
from v$sql 
where buffer_gets > 1000000 
or disk_reads > 100000 
or executions > 50000 

Can you remove elements from a std::list while iterating through it?

Removal invalidates only the iterators that point to the elements that are removed.

So in this case after removing *i , i is invalidated and you cannot do increment on it.

What you can do is first save the iterator of element that is to be removed , then increment the iterator and then remove the saved one.

Combining border-top,border-right,border-left,border-bottom in CSS

Or if all borders have same style, just:

border:10px;

Can a java file have more than one class?

Yes ! .java file can contain only one public class.

If you want these two classes to be public they have to be put into two .java files: A.java and B.java.

Failed Apache2 start, no error log

You have following ways to make it work:

  1. Delete /var/run/apache2/apache2.pid then check if its working

  2. You can disable SELinux and then check if it works. You can disable SELinux permanantly or temporarily by using https://linux4one.com/how-to-disable-selinux-on-centos-7/ tutorial

array filter in python?

No, there is no build in function in python to do this, because simply:

set(A)- set(subset_of_A)

will provide you the answer.

How to set the allowed url length for a nginx request (error code: 414, uri too large)

From: http://nginx.org/r/large_client_header_buffers

Syntax: large_client_header_buffers number size ;
Default: large_client_header_buffers 4 8k;
Context: http, server

Sets the maximum number and size of buffers used for reading large client request header. A request line cannot exceed the size of one buffer, or the 414 (Request-URI Too Large) error is returned to the client. A request header field cannot exceed the size of one buffer as well, or the 400 (Bad Request) error is returned to the client. Buffers are allocated only on demand. By default, the buffer size is equal to 8K bytes. If after the end of request processing a connection is transitioned into the keep-alive state, these buffers are released.

so you need to change the size parameter at the end of that line to something bigger for your needs.

displaying a string on the textview when clicking a button in android

public void onCreate(Bundle savedInstanceState) 
{
    setContentView(R.layout.main);
    super.onCreate(savedInstanceState);

    mybtn = (Button)findViewById(R.id.mybtn);
    txtView=(TextView)findViewById(R.id.txtView);

    mybtn .setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            txtView.SetText("Your Message");
        }
    });
}

Android video streaming example

Your problem is most likely with the video file, not the code. Your video is most likely not "safe for streaming". See where to place videos to stream android for more.

Disabling of EditText in Android

As android:editable="false" is depricated.You can use InputType TYPE_NULL on EditText

use like this :

editText.setInputType(InputType.TYPE_NULL);

Fatal Error :1:1: Content is not allowed in prolog

There are certainly some weird characters (e.g. BOM) or some whitespace before the XML preamble (<?xml ...?>)?

How to add app icon within phonegap projects?

Just noting that I've just changed my config.xml to look like Sebastian's example.

Something that's also helpful in debugging all this especially if you don't do local builds... is to download the XAP/IPA/APK files as built from PhoneGap cloud and create folders for each. Rename each file with a .ZIP extension and extract the contents of each to their respective folders. So basically, you can now see what's in the package that will be shipped to the phone.

Doing this, I can see that for the Microsoft Phone platform it's largely ignoring all my attempts at replacing the icon or splash screen. If you then replace the ApplicationIcon.png and SplashScreenImage.jpg, then re-zip the folderset and rename it again as a .XAP file you can then deploy it to your phone and it will work perfectly. Somehow, there's a way of just getting the PhoneGap build to turn your icon.png and icon.jpg into those two files. Perhaps Masood's suggestion is a possibility here and utilize a hook script.

Doing the same for the .IPA file (iOS) results in several files like icon-something.png at the parent level above www. They all appear to be blank.

Doing the same for the .APK file (Android) results in a res/drawable-something set of folders and it appears to have my icon.png in each one. It's the closest to a success I can claim at the moment.

Check if object exists in JavaScript

set Textbox value to one frame to inline frame using div alignmnt tabbed panel. So first of all, before set the value we need check selected tabbed panels frame available or not using following codes:

Javascript Code :

/////////////////////////////////////////
<script>

function set_TextID()
            {
                try
                    {
                        if(!parent.frames["entry"])
                            {
                            alert("Frame object not found");    
                            }
                            else
                            {
                                var setText=document.getElementById("formx").value;
                                parent.frames["entry"].document.getElementById("form_id").value=setText;
                            }
                            if(!parent.frames["education"])
                            {
                            alert("Frame object not found");    

                            }
                            else
                            {
                                var setText=document.getElementById("formx").value;
                                parent.frames["education"].document.getElementById("form_id").value=setText;
                            }
                            if(!parent.frames["contact"])
                            {
                            alert("Frame object not found");    

                            }
                            else
                            {
                                var setText=document.getElementById("formx").value;
                                parent.frames["contact"].document.getElementById("form_id").value=setText;
                            }

                        }catch(exception){}
                }

</script>

Attach event to dynamic elements in javascript

You can do something similar to this:

// Get the parent to attatch the element into
var parent = document.getElementsByTagName("ul")[0];

// Create element with random id
var element = document.createElement("li");
element.id = "li-"+Math.floor(Math.random()*9999);

// Add event listener
element.addEventListener("click", EVENT_FN);

// Add to parent
parent.appendChild(element);

max value of integer

The strict equivalent of the java int is long int in C.

Edit: If int32_t is defined, then it is the equivalent in terms of precision. long int guarantee the precision of the java int, because it is guarantee to be at least 32 bits in size.

OpenJDK availability for Windows OS

For Java 12 onwards, official General-Availability (GA) and Early-Access (EA) Windows 64-bit builds of the OpenJDK (GPL2 + Classpath Exception) from Oracle are available as tar.gz/zip from the JDK website.

If you prefer an installer, there are several distributions. There is a public Google Doc and Blog post by the Java Champions community which lists the best-supported OpenJDK distributions. Currently, these are:

How to sort an array of integers correctly

TypeScript variant

const compareNumbers = (a: number, b: number): number => a - b

myArray.sort(compareNumbers)

How to implement class constants?

Either use readOnly modifier with the constant one needs to declare or one might declare a constant outside the class and use it specifically only in the required class using get operator.

Find JavaScript function definition in Chrome

I had a similar problem finding the source of an object's method. The object name was myTree and its method was load. I put a breakpoint on the line that the method was called. By reloading the page, the execution stopped at that point. Then on the DevTools console, I typed the object along with the method name, i.e. myTree.load and hit Enter. The definition of the method was printed on the console:

enter image description here

Also, by right click on the definition, you can go to its definition in the source code:

enter image description here

Random String Generator Returning Same String

Another sample (tested in vs2013):

    Random R = new Random();
    public static string GetRandomString(int Length)
    {
        char[] ArrRandomChar = new char[Length];
        for (int i = 0; i < Length; i++)
            ArrRandomChar[i] = (char)('a' + R.Next(0, 26));
        return new string(ArrRandomChar);
    }

    string D = GetRandomString(12);

Implemented by myself.

Query an XDocument for elements by name at any depth

Following @Francisco Goldenstein answer, I wrote an extension method

using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;

namespace Mediatel.Framework
{
    public static class XDocumentHelper
    {
        public static IEnumerable<XElement> DescendantElements(this XDocument xDocument, string nodeName)
        {
            return xDocument.Descendants().Where(p => p.Name.LocalName == nodeName);
        }
    }
}

How can I generate an MD5 hash?

Bombe's answer is correct, however note that unless you absolutely must use MD5 (e.g. forced on you for interoperability), a better choice is SHA1 as MD5 has weaknesses for long term use.

I should add that SHA1 also has theoretical vulnerabilities, but not as severe. The current state of the art in hashing is that there are a number of candidate replacement hash functions but none have yet emerged as the standard best practice to replace SHA1. So, depending on your needs you would be well advised to make your hash algorithm configurable so it can be replaced in future.

Java :Add scroll into text area

My naive assumption was that the size of scroll pane will be determined automatically...

The only solution that actually worked for me was explicitly seeting bounds of JScrollPane:

import javax.swing.*;

public class MyFrame extends JFrame {

    public MyFrame()
    {
        setBounds(100, 100, 491, 310);
        getContentPane().setLayout(null);

        JTextArea textField = new JTextArea();
        textField.setEditable(false);

        String str = "";
        for (int i = 0; i < 50; ++i)
            str += "Some text\n";
        textField.setText(str);

        JScrollPane scroll = new JScrollPane(textField);
        scroll.setBounds(10, 11, 455, 249);                     // <-- THIS

        getContentPane().add(scroll);
        setLocationRelativeTo ( null );
    }
}

Maybe it will help some future visitors :)

How to use a typescript enum value in an Angular2 ngSwitch statement

as of rc.6 / final

...

export enum AdnetNetworkPropSelector {
    CONTENT,
    PACKAGE,
    RESOURCE
}

<div style="height: 100%">
          <div [ngSwitch]="propSelector">
                 <div *ngSwitchCase="adnetNetworkPropSelector.CONTENT">
                      <AdnetNetworkPackageContentProps [setAdnetContentModels]="adnetNetworkPackageContent.selectedAdnetContentModel">
                                    </AdnetNetworkPackageContentProps>
                  </div>
                 <div *ngSwitchCase="adnetNetworkPropSelector.PACKAGE">
                </div>
            </div>              
        </div>


export class AdnetNetwork {       
    private adnetNetworkPropSelector = AdnetNetworkPropSelector;
    private propSelector = AdnetNetworkPropSelector.CONTENT;
}

Import file size limit in PHPMyAdmin

For uploading large files through PHPMyAdmin, follow these steps:

Step 1: Open your php.ini file.

Step 2: Upgrading Memory Limit:

memory_limit = 750M

Step 3: Upgrading Maximum size to post:

post_max_size = 750M

Step 4: Upgrading Maximum file-size to upload:

upload_max_filesize = 1000M

Step 5: Upgrading Maximum Execution Time:

max_execution_time = 5000

Step 6: Upgrading Maximum Input Time:

max_input_time = 3000

Step 7: Restart your xampp control panel.

Create directories using make file

make in, and off itself, handles directory targets just the same as file targets. So, it's easy to write rules like this:

outDir/someTarget: Makefile outDir
    touch outDir/someTarget

outDir:
    mkdir -p outDir

The only problem with that is, that the directories timestamp depends on what is done to the files inside. For the rules above, this leads to the following result:

$ make
mkdir -p outDir
touch outDir/someTarget
$ make
touch outDir/someTarget
$ make
touch outDir/someTarget
$ make
touch outDir/someTarget

This is most definitely not what you want. Whenever you touch the file, you also touch the directory. And since the file depends on the directory, the file consequently appears to be out of date, forcing it to be rebuilt.

However, you can easily break this loop by telling make to ignore the timestamp of the directory. This is done by declaring the directory as an order-only prerequsite:

# The pipe symbol tells make that the following prerequisites are order-only
#                           |
#                           v
outDir/someTarget: Makefile | outDir
    touch outDir/someTarget

outDir:
    mkdir -p outDir

This correctly yields:

$ make
mkdir -p outDir
touch outDir/someTarget
$ make
make: 'outDir/someTarget' is up to date.

TL;DR:

Write a rule to create the directory:

$(OUT_DIR):
    mkdir -p $(OUT_DIR)

And have the targets for the stuff inside depend on the directory order-only:

$(OUT_DIR)/someTarget: ... | $(OUT_DIR)

How to while loop until the end of a file in Python without checking for empty line?

I discovered while following the above suggestions that for line in f: does not work for a pandas dataframe (not that anyone said it would) because the end of file in a dataframe is the last column, not the last row. for example if you have a data frame with 3 fields (columns) and 9 records (rows), the for loop will stop after the 3rd iteration, not after the 9th iteration. Teresa

Does VBA contain a comment block syntax?

prefix the comment with a single-quote. there is no need for an "end" tag.

'this is a comment

Extend to multiple lines using the line-continuation character, _:

'this is a multi-line _
   comment

This is an option in the toolbar to select a line(s) of code and comment/uncomment:

enter image description here

Passing null arguments to C# methods

Yes. There are two kinds of types in .NET: reference types and value types.

References types (generally classes) are always referred to by references, so they support null without any extra work. This means that if a variable's type is a reference type, the variable is automatically a reference.

Value types (e.g. int) by default do not have a concept of null. However, there is a wrapper for them called Nullable. This enables you to encapsulate the non-nullable value type and include null information.

The usage is slightly different, though.

// Both of these types mean the same thing, the ? is just C# shorthand.
private void Example(int? arg1, Nullable<int> arg2)
{
    if (arg1.HasValue)
        DoSomething();

    arg1 = null; // Valid.
    arg1 = 123;  // Also valid.

    DoSomethingWithInt(arg1); // NOT valid!
    DoSomethingWithInt(arg1.Value); // Valid.
}

Single-threaded apartment - cannot instantiate ActiveX control

If you used [STAThread] to the main entry of your application and still get the error you may need to make a Thread-Safe call to the control... something like below. In my case with the same problem the following solution worked!

Private void YourFunc(..)
{
    if (this.InvokeRequired)
    {
        Invoke(new MethodInvoker(delegate()
        {
           // Call your method YourFunc(..);
        }));
    }
    else
    {
        ///
    }

jQuery ajax upload file in asp.net mvc

Upload files using AJAX in ASP.Net MVC

Things have changed since HTML5

JavaScript

document.getElementById('uploader').onsubmit = function () {
    var formdata = new FormData(); //FormData object
    var fileInput = document.getElementById('fileInput');
    //Iterating through each files selected in fileInput
    for (i = 0; i < fileInput.files.length; i++) {
        //Appending each file to FormData object
        formdata.append(fileInput.files[i].name, fileInput.files[i]);
    }
    //Creating an XMLHttpRequest and sending
    var xhr = new XMLHttpRequest();
    xhr.open('POST', '/Home/Upload');
    xhr.send(formdata);
    xhr.onreadystatechange = function () {
        if (xhr.readyState == 4 && xhr.status == 200) {
            alert(xhr.responseText);
        }
    }
    return false;
}   

Controller

public JsonResult Upload()
{
    for (int i = 0; i < Request.Files.Count; i++)
    {
        HttpPostedFileBase file = Request.Files[i]; //Uploaded file
        //Use the following properties to get file's name, size and MIMEType
        int fileSize = file.ContentLength;
        string fileName = file.FileName;
        string mimeType = file.ContentType;
        System.IO.Stream fileContent = file.InputStream;
        //To save file, use SaveAs method
        file.SaveAs(Server.MapPath("~/")+ fileName ); //File will be saved in application root
    }
    return Json("Uploaded " + Request.Files.Count + " files");
}

EDIT : The HTML

<form id="uploader">
    <input id="fileInput" type="file" multiple>
    <input type="submit" value="Upload file" />
</form>

LaTeX table positioning

Not necessary to use \restylefloat and destroys other options, like caption placement. just use [H] or [!h] after \begin{table}.

How do I timestamp every ping result?

You did not specify any time stamp or interval for how long you would require such output, so I considered it to be an infinite loop. You can change it accordingly as per your need.

while true
do
   echo -e "`date`|`ping -n -c 1 <IP_TO_PING>|grep 'bytes from'`"
   sleep 2
done

How to check string length and then select substring in Sql Server

To conditionally check the length of the string, use CASE.

SELECT  CASE WHEN LEN(comments) <= 60 
             THEN comments
             ELSE LEFT(comments, 60) + '...'
        END  As Comments
FROM    myView

How to generate a QR Code for an Android application?

Here is my simple and working function to generate a Bitmap! I Use ZXing1.3.jar only! I've also set Correction Level to High!

PS: x and y are reversed, it's normal, because bitMatrix reverse x and y. This code works perfectly with a square image.

public static Bitmap generateQrCode(String myCodeText) throws WriterException {
    Hashtable<EncodeHintType, ErrorCorrectionLevel> hintMap = new Hashtable<EncodeHintType, ErrorCorrectionLevel>();
    hintMap.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H); // H = 30% damage

    QRCodeWriter qrCodeWriter = new QRCodeWriter();

    int size = 256;

    ByteMatrix bitMatrix = qrCodeWriter.encode(myCodeText,BarcodeFormat.QR_CODE, size, size, hintMap);
    int width = bitMatrix.width();
    Bitmap bmp = Bitmap.createBitmap(width, width, Bitmap.Config.RGB_565);
    for (int x = 0; x < width; x++) {
        for (int y = 0; y < width; y++) {
            bmp.setPixel(y, x, bitMatrix.get(x, y)==0 ? Color.BLACK : Color.WHITE);
        }
    }
    return bmp;
}

EDIT

It's faster to use bitmap.setPixels(...) with a pixel int array instead of bitmap.setPixel one by one:

        BitMatrix bitMatrix = writer.encode(inputValue, BarcodeFormat.QR_CODE, size, size);
        int width = bitMatrix.getWidth();
        int height = bitMatrix.getHeight();
        int[] pixels = new int[width * height];
        for (int y = 0; y < height; y++) {
            int offset = y * width;
            for (int x = 0; x < width; x++) {
                pixels[offset + x] = bitMatrix.get(x, y) ? BLACK : WHITE;
            }
        }

        bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        bitmap.setPixels(pixels, 0, width, 0, 0, width, height);

The performance impact of using instanceof in Java

instanceof is very efficient, so your performance is unlikely to suffer. However, using lots of instanceof suggests a design issue.

If you can use xClass == String.class, this is faster. Note: you don't need instanceof for final classes.

ASP.NET Core Web API Authentication

In this public Github repo https://github.com/boskjoett/BasicAuthWebApi you can see a simple example of a ASP.NET Core 2.2 web API with endpoints protected by Basic Authentication.

How to find which columns contain any NaN value in Pandas dataframe

This worked for me,

1. For getting Columns having at least 1 null value. (column names)

data.columns[data.isnull().any()]

2. For getting Columns with count, with having at least 1 null value.

data[data.columns[data.isnull().any()]].isnull().sum()

[Optional] 3. For getting percentage of the null count.

data[data.columns[data.isnull().any()]].isnull().sum() * 100 / data.shape[0]

char initial value in Java

i would just do:

char x = 0; //Which will give you an empty value of character

Fatal error: Call to a member function fetch_assoc() on a non-object

I happen to miss spaces in my query and this error comes.

Ex: $sql= "SELECT * FROM";
$sql .= "table1";

Though the example might look simple, when coding complex queries, the probability for this error is high. I was missing space before word "table1".

HttpWebRequest using Basic authentication

First thing, for me ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 worked instead of Ssl3.

Secondly, I had to send the Basic Auth request along with some data (form-urlencoded). Here is the complete sample which worked for me perfectly, after trying many solutions.

Disclaimer: The code below is a mixture of solutions found on this link and some other stackoverflow links, thanks for the useful information.

        ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
        String username = "user_name";
        String password = "password";
        String encoded = System.Convert.ToBase64String(System.Text.Encoding.GetEncoding("ISO-8859-1").GetBytes(username + ":" + password));

        //Form Data
        var formData = "var1=val1&var2=val2";
        var encodedFormData = Encoding.ASCII.GetBytes(formData);

        HttpWebRequest request = (HttpWebRequest)WebRequest.Create("THE_URL");
        request.ContentType = "application/x-www-form-urlencoded";
        request.Method = "POST";
        request.ContentLength = encodedFormData.Length;
        request.Headers.Add("Authorization", "Basic " + encoded);
        request.PreAuthenticate = true;

        using (var stream = request.GetRequestStream())
        {
            stream.Write(encodedFormData, 0, encodedFormData.Length);
        }

        HttpWebResponse response = (HttpWebResponse)request.GetResponse();
        var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();

How do you split a list into evenly sized chunks?

letting r be the chunk size and L be the initial list, you can do.

chunkL = [ [i for i in L[r*k:r*(k+1)] ] for k in range(len(L)/r)] 

Spring - No EntityManager with actual transaction available for current thread - cannot reliably process 'persist' call

I removed the mode from

<tx:annotation-driven mode="aspectj"
transaction-manager="transactionManager" />

to make this work

python: how to send mail with TO, CC and BCC?

Key thing is to add the recipients as a list of email ids in your sendmail call.

import smtplib
from email.mime.multipart import MIMEMultipart

me = "[email protected]"
to = "[email protected]"
cc = "[email protected],[email protected]"
bcc = "[email protected],[email protected]"

rcpt = cc.split(",") + bcc.split(",") + [to]
msg = MIMEMultipart('alternative')
msg['Subject'] = "my subject"
msg['To'] = to
msg['Cc'] = cc
msg.attach(my_msg_body)
server = smtplib.SMTP("localhost") # or your smtp server
server.sendmail(me, rcpt, msg.as_string())
server.quit()

More than 1 row in <Input type="textarea" />

As said by Sparky in comments on many answers to this question, there is NOT any textarea value for the type attribute of the input tag.

On other terms, the following markup is not valid :

<input type="textarea" />

And the browser replaces it by the default :

<input type="text" />

To define a multi-lines text input, use :

<textarea></textarea>

See the textarea element documentation for more details.

Which TensorFlow and CUDA version combinations are compatible?

if you are coding in jupyter notebook, and want to check which cuda version tf is using, run the follow command directly into jupyter cell:

!conda list cudatoolkit

!conda list cudnn

and to check if the gpu is visible to tf:

tf.test.is_gpu_available(
    cuda_only=False, min_cuda_compute_capability=None
)

Operator overloading in Java

Unlike C++, Java does not support user defined operator overloading. The overloading is done internally in java.

We can take +(plus) for example:

int a = 2 + 4;
string = "hello" + "world";

Here, plus adds two integer numbers and concatenates two strings. So we can say that Java supports internal operator overloading but not user defined.

How to make Scrollable Table with fixed headers using CSS

I can think of a cheeky way to do it, I don't think this will be the best option but it will work.

Create the header as a separate table then place the other in a div and set a max size, then allow the scroll to come in by using overflow.

_x000D_
_x000D_
table {_x000D_
  width: 500px;_x000D_
}_x000D_
_x000D_
.scroll {_x000D_
  max-height: 60px;_x000D_
  overflow: auto;_x000D_
}
_x000D_
<table border="1">_x000D_
  <tr>_x000D_
  <th>head1</th>_x000D_
  <th>head2</th>_x000D_
  <th>head3</th>_x000D_
  <th>head4</th>_x000D_
  </tr>_x000D_
</table>_x000D_
<div class="scroll">_x000D_
  <table>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>More Text</td><td>More Text</td><td>More Text</td><td>More Text</td></tr>_x000D_
    <tr><td>Text Text</td><td>Text Text</td><td>Text Text</td><td>Text Text</td></tr>_x000D_
    <tr><td>Even More Text Text</td><td>Even More Text Text</td><td>Even More Text Text</td><td>Even More Text Text</td></tr>_x000D_
  </table>_x000D_
</div>
_x000D_
_x000D_
_x000D_

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

I agree with using events for this. Since I suspect that you're building an MDI-application (since you create many child forms) and creates windows dynamically and might not know when to unsubscribe from events, I would recommend that you take a look at Weak Event Patterns. Alas, this is only available for framework 3.0 and 3.5 but something similar can be implemented fairly easy with weak references.

However, if you want to find a control in a form based on the form's reference, it's not enough to simply look at the form's control collection. Since every control have it's own control collection, you will have to recurse through them all to find a specific control. You can do this with these two methods (which can be improved).

public static Control FindControl(Form form, string name)
{
    foreach (Control control in form.Controls)
    {
        Control result = FindControl(form, control, name);

        if (result != null)
            return result;
    }

    return null;
}

private static Control FindControl(Form form, Control control, string name)
{
    if (control.Name == name) {
        return control;
    }

    foreach (Control subControl in control.Controls)
    {
        Control result = FindControl(form, subControl, name);

        if (result != null)
            return result;
    }

    return null;
}

Can't find System.Windows.Media namespace?

For Visual Studio 2017

Find "References" in Solution explorer

Right click "References"

Choose "Add Reference..."

Find "Presentation.Core" list and check checkbox

Click OK

How to add image in Flutter

When you adding assets directory in pubspec.yaml file give more attention in to spaces

this is wrong

flutter:
   assets:
    - assets/images/lake.jpg

This is the correct way,

flutter:
  assets:
    - assets/images/

How to listen for changes to a MongoDB collection?

MongoDB has what is called capped collections and tailable cursors that allows MongoDB to push data to the listeners.

A capped collection is essentially a collection that is a fixed size and only allows insertions. Here's what it would look like to create one:

db.createCollection("messages", { capped: true, size: 100000000 })

MongoDB Tailable cursors (original post by Jonathan H. Wage)

Ruby

coll = db.collection('my_collection')
cursor = Mongo::Cursor.new(coll, :tailable => true)
loop do
  if doc = cursor.next_document
    puts doc
  else
    sleep 1
  end
end

PHP

$mongo = new Mongo();
$db = $mongo->selectDB('my_db')
$coll = $db->selectCollection('my_collection');
$cursor = $coll->find()->tailable(true);
while (true) {
    if ($cursor->hasNext()) {
        $doc = $cursor->getNext();
        print_r($doc);
    } else {
        sleep(1);
    }
}

Python (by Robert Stewart)

from pymongo import Connection
import time

db = Connection().my_db
coll = db.my_collection
cursor = coll.find(tailable=True)
while cursor.alive:
    try:
        doc = cursor.next()
        print doc
    except StopIteration:
        time.sleep(1)

Perl (by Max)

use 5.010;

use strict;
use warnings;
use MongoDB;

my $db = MongoDB::Connection->new;
my $coll = $db->my_db->my_collection;
my $cursor = $coll->find->tailable(1);
for (;;)
{
    if (defined(my $doc = $cursor->next))
    {
        say $doc;
    }
    else
    {
        sleep 1;
    }
}

Additional Resources:

Ruby/Node.js Tutorial which walks you through creating an application that listens to inserts in a MongoDB capped collection.

An article talking about tailable cursors in more detail.

PHP, Ruby, Python, and Perl examples of using tailable cursors.

What's the opposite of 'make install', i.e. how do you uninstall a library in Linux?

If sudo make uninstall is unavailable:

In a Debian based system, instead of (or after*) doing make install you can run sudo checkinstall to make a .deb file that gets automatically installed. You can then remove it using the system package manager (e.g. apt/synaptic/aptitude/dpkg). Checkinstall also supports creating other types of package, e.g. RPM.

See also http://community.linuxmint.com/tutorial/view/162 and some basic checkinstall usage and debian checkinstall package.


*: If you're reading this after having installed with make install you can still follow the above instructions and do a dpkg -r $PACKAGE_NAME_YOU_CHOSEN afterwards.

How to get a unique computer identifier in Java (like disk ID or motherboard ID)?

What do you want to do with this unique ID? Maybe you can do what you want without this ID.

The MAC address maybe is one option but this is not an trusted unique ID because the user can change the MAC address of a computer.

To get the motherboard or processor ID check on this link.

Tainted canvases may not be exported

Seems like you are using an image from a URL that has not set correct Access-Control-Allow-Origin header and hence the issue.. You can fetch that image from your server and get it from your server to avoid CORS issues..