Programs & Examples On #Add on

Add-on, a.k.a. Plug-in is a set of components that enhances the existing, or adds new capabilities to a software application.

Recommended add-ons/plugins for Microsoft Visual Studio

  • Resharper (Agree it sucks you have to pay extra to get this, but well work the money)
  • GhostDoc (Takes away any excuse for not having comments in your code)

  • PowerCommands for VS 2008 (Forgot I even had this installed because it just adds a the little things that should have been there all along)

Java Command line arguments

Your main method has a String[] argument. That contain the arguments that have been passed to your applications (it's often called args, but that's not a requirement).

Displaying one div on top of another

Here is the jsFiddle

#backdrop{
    border: 2px solid red;
    width: 400px;
    height: 200px;
    position: absolute;
}

#curtain {
    border: 1px solid blue;
    width: 400px;
    height: 200px;
    position: absolute;
}

Use Z-index to move the one you want on top.

Convert floats to ints in Pandas?

To modify the float output do this:

df= pd.DataFrame(range(5), columns=['a'])
df.a = df.a.astype(float)
df

Out[33]:

          a
0 0.0000000
1 1.0000000
2 2.0000000
3 3.0000000
4 4.0000000

pd.options.display.float_format = '{:,.0f}'.format
df

Out[35]:

   a
0  0
1  1
2  2
3  3
4  4

What is the proper way to check and uncheck a checkbox in HTML5?

Complementary answer to Robert's answer http://jsfiddle.net/ak9Sb/ in jQuery

When getting/setting checkbox state, one may encounter these phenomenons:

.trigger("click");

Does check an unchecked checkbox, but do not add the checked attribute. If you use triggers, do not try to get the state with "checked" attribute.

.attr("checked", "");

Does not uncheck the checkbox...

batch/bat to copy folder and content at once

For Folder Copy You can Use

robocopy C:\Source D:\Destination /E

For File Copy

copy D:\Sourcefile.txt D:\backup\Destinationfile.txt /Y 

Delete file in some folder last modify date more than some day

forfiles -p "D:\FolderPath" -s -m *.[Filetype eg-->.txt] -d -[Numberof dates] -c "cmd /c del @PATH"

And you can Shedule task in windows perform this task automatically in specific time.

Redirect to new Page in AngularJS using $location

$location won't help you with external URLs, use the $window service instead:

$window.location.href = 'http://www.google.com';

Note that you could use the window object, but it is bad practice since $window is easily mockable whereas window is not.

Calculate date from week number

This one worked for me, it also have the advantage of expecting a cultureinfo as parameter to test the formula with different cultures. If empty, it gets the current culture info... valid values are like: "it", "en-us", "fr", ... ando so on. The trick is to subtract the week number of the first day of the year, that may be 1 to indicate that the first day is within the first week. Hope this helps.

Public Shared Function FirstDayOfWeek(ByVal year As Integer, ByVal weekNumber As Integer, ByVal culture As String) As Date
    Dim cInfo As System.Globalization.CultureInfo
    If culture = "" Then
        cInfo = System.Globalization.CultureInfo.CurrentCulture
    Else
        cInfo = System.Globalization.CultureInfo.CreateSpecificCulture(culture)
    End If
    Dim calendar As System.Globalization.Calendar = cInfo.Calendar
    Dim firstOfYear As DateTime = New DateTime(year, 1, 1, calendar)
    Dim firstDayWeek As Integer = calendar.GetWeekOfYear(firstOfYear, cInfo.DateTimeFormat.CalendarWeekRule, cInfo.DateTimeFormat.FirstDayOfWeek)
    weekNumber -= firstDayWeek
    Dim targetDay As DateTime = calendar.AddWeeks(firstOfYear, weekNumber)
    Dim fDayOfWeek As DayOfWeek = cInfo.DateTimeFormat.FirstDayOfWeek

    While (targetDay.DayOfWeek <> fDayOfWeek)
        targetDay = targetDay.AddDays(-1)
    End While
    Return targetDay
End Function

convert nan value to zero

Where A is your 2D array:

import numpy as np
A[np.isnan(A)] = 0

The function isnan produces a bool array indicating where the NaN values are. A boolean array can by used to index an array of the same shape. Think of it like a mask.

Easier way to create circle div than using an image?

_x000D_
_x000D_
.circle {_x000D_
 height: 20rem;_x000D_
 width: 20rem;_x000D_
 border-radius: 50%;_x000D_
 background-color: #EF6A6A;_x000D_
}
_x000D_
<div class="circle"></div>
_x000D_
_x000D_
_x000D_

Git error: "Host Key Verification Failed" when connecting to remote repository

Reason seems to be that the public key of the remote host is not stored or different from the stored one. (Be aware of security issues, see Greg Bacon's answer for details.)

I was used to git clone prompting me in this case:

The authenticity of host 'host.net (10.0.0.42)' can't be established.
ECDSA key fingerprint is 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00.
Are you sure you want to continue connecting (yes/no)?

Not sure, why this error is thrown instead. Could be the configuration of your shell or the git SSH command.
Anyhow, you can get the same prompt by running ssh [email protected].

stringstream, string, and char* conversion confusion

In this line:

const char* cstr2 = ss.str().c_str();

ss.str() will make a copy of the contents of the stringstream. When you call c_str() on the same line, you'll be referencing legitimate data, but after that line the string will be destroyed, leaving your char* to point to unowned memory.

Convert file path to a file URI?

UrlCreateFromPath to the rescue! Well, not entirely, as it doesn't support extended and UNC path formats, but that's not so hard to overcome:

public static Uri FileUrlFromPath(string path)
{
    const string prefix = @"\\";
    const string extended = @"\\?\";
    const string extendedUnc = @"\\?\UNC\";
    const string device = @"\\.\";
    const StringComparison comp = StringComparison.Ordinal;

    if(path.StartsWith(extendedUnc, comp))
    {
        path = prefix+path.Substring(extendedUnc.Length);
    }else if(path.StartsWith(extended, comp))
    {
        path = prefix+path.Substring(extended.Length);
    }else if(path.StartsWith(device, comp))
    {
        path = prefix+path.Substring(device.Length);
    }

    int len = 1;
    var buffer = new StringBuilder(len);
    int result = UrlCreateFromPath(path, buffer, ref len, 0);
    if(len == 1) Marshal.ThrowExceptionForHR(result);

    buffer.EnsureCapacity(len);
    result = UrlCreateFromPath(path, buffer, ref len, 0);
    if(result == 1) throw new ArgumentException("Argument is not a valid path.", "path");
    Marshal.ThrowExceptionForHR(result);
    return new Uri(buffer.ToString());
}

[DllImport("shlwapi.dll", CharSet=CharSet.Auto, SetLastError=true)]
static extern int UrlCreateFromPath(string path, StringBuilder url, ref int urlLength, int reserved);

In case the path starts with with a special prefix, it gets removed. Although the documentation doesn't mention it, the function outputs the length of the URL even if the buffer is smaller, so I first obtain the length and then allocate the buffer.

Some very interesting observation I had is that while "\\device\path" is correctly transformed to "file://device/path", specifically "\\localhost\path" is transformed to just "file:///path".

The WinApi function managed to encode special characters, but leaves Unicode-specific characters unencoded, unlike the Uri construtor. In that case, AbsoluteUri contains the properly encoded URL, while OriginalString can be used to retain the Unicode characters.

Best way to convert strings to symbols in hash

if you're using Rails, it is much simpler - you can use a HashWithIndifferentAccess and access the keys both as String and as Symbols:

my_hash.with_indifferent_access 

see also:

http://api.rubyonrails.org/classes/ActiveSupport/HashWithIndifferentAccess.html


Or you can use the awesome "Facets of Ruby" Gem, which contains a lot of extensions to Ruby Core and Standard Library classes.

  require 'facets'
  > {'some' => 'thing', 'foo' => 'bar'}.symbolize_keys
    =>  {:some=>"thing", :foo=>"bar}

see also: http://rubyworks.github.io/rubyfaux/?doc=http://rubyworks.github.io/facets/docs/facets-2.9.3/core.json#api-class-Hash

How to initialize a vector of vectors on a struct?

You use new to perform dynamic allocation. It returns a pointer that points to the dynamically allocated object.

You have no reason to use new, since A is an automatic variable. You can simply initialise A using its constructor:

vector<vector<int> > A(dimension, vector<int>(dimension));

Changing CSS style from ASP.NET code

VB Version:

Class:

Protected divControl As System.Web.UI.HtmlControls.HtmlGenericControl

OnLoad/Other function:

divControl.Style("height") = "200px"

I've never tried the Add method with the styles. What if the height already exists on the DIV?

Angular 4 checkbox change value

This works for me, angular 9:

component.html file:

<mat-checkbox (change)="checkValue($event)">text</mat-checkbox>

component.ts file:

checkValue(e){console.log(e.target.checked)}

How can I check the syntax of Python script without executing it?

Thanks to the above answers @Rosh Oxymoron. I improved the script to scan all files in a dir that are python files. So for us lazy folks just give it the directory and it will scan all the files in that directory that are python.

import sys
import glob, os

os.chdir(sys.argv[1])
for file in glob.glob("*.py"):
    source = open(file, 'r').read() + '\n'
    compile(source, file, 'exec')

Save this as checker.py and run python checker.py ~/YOURDirectoryTOCHECK

How to set java_home on Windows 7?

Run Eclipse as Administrator.

That solved my problem. I'm still digging for the logic behind it.

Converting byte array to string in javascript

Try the new Text Encoding API:

_x000D_
_x000D_
// create an array view of some valid bytes_x000D_
let bytesView = new Uint8Array([104, 101, 108, 108, 111]);_x000D_
_x000D_
console.log(bytesView);_x000D_
_x000D_
// convert bytes to string_x000D_
// encoding can be specfied, defaults to utf-8 which is ascii._x000D_
let str = new TextDecoder().decode(bytesView); _x000D_
_x000D_
console.log(str);_x000D_
_x000D_
// convert string to bytes_x000D_
// encoding can be specfied, defaults to utf-8 which is ascii._x000D_
let bytes2 = new TextEncoder().encode(str);_x000D_
_x000D_
// look, they're the same!_x000D_
console.log(bytes2);_x000D_
console.log(bytesView);
_x000D_
_x000D_
_x000D_

Android Camera Preview Stretched

I figured out what's the problem - it is with orientation changes. If you change camera orientation to 90 or 270 degrees than you need to swap width and height of supported sizes and all will be ok.

Also surface view should lie in a frame layout and have center gravity.

Here is example on C# (Xamarin):

public void SurfaceChanged(ISurfaceHolder holder, Android.Graphics.Format format, int width, int height)
{
    _camera.StopPreview();

    // find best supported preview size

    var parameters = _camera.GetParameters();
    var supportedSizes = parameters.SupportedPreviewSizes;
    var bestPreviewSize = supportedSizes
        .Select(x => new { Width = x.Height, Height = x.Width, Original = x }) // HACK swap height and width because of changed orientation to 90 degrees
        .OrderBy(x => Math.Pow(Math.Abs(x.Width - width), 3) + Math.Pow(Math.Abs(x.Height - height), 2))
        .First();

    if (height == bestPreviewSize.Height && width == bestPreviewSize.Width)
    {
        // start preview if best supported preview size equals current surface view size

        parameters.SetPreviewSize(bestPreviewSize.Original.Width, bestPreviewSize.Original.Height);
        _camera.SetParameters(parameters);
        _camera.StartPreview();
    }
    else
    {
        // if not than change surface view size to best supported (SurfaceChanged will be called once again)

        var layoutParameters = _surfaceView.LayoutParameters;
        layoutParameters.Width = bestPreviewSize.Width;
        layoutParameters.Height = bestPreviewSize.Height;
        _surfaceView.LayoutParameters = layoutParameters;
    }
}

Pay attention that camera parameters should be set as original size (not swapped), and surface view size should be swapped.

ES6 exporting/importing in index file

You can easily re-export the default import:

export {default as Comp1} from './Comp1.jsx';
export {default as Comp2} from './Comp2.jsx';
export {default as Comp3} from './Comp3.jsx';

There also is a proposal for ES7 ES8 that will let you write export Comp1 from '…';.

Git push hangs when pushing to Github?

I also had an issue where git hangs on the "Writing objects" part on Windows 7 (using msysgit, the default windows client from git) and this is the first hit I got in google, so I will also post my answer here.

git config --global core.askpass "git-gui--askpass" did not work unfotunately, but after some researching I found the tip on Git push halts on "Writing Objects: 100%" to use git config –global sendpack.sideband false which worked perfectly.

I can finally push from the commandline again!

Where can I find WcfTestClient.exe (part of Visual Studio)

For Visual studio 2013, Windows 8...

C:\Program Files (x86)\Microsoft Visual Studio 12.0\Common7\IDE\WcfTestClient.exe

npm install Error: rollbackFailedOptional

Try this

npm config rm proxy
npm config rm https-proxy

Generating a PNG with matplotlib when DISPLAY is undefined

The main problem is that (on your system) matplotlib chooses an x-using backend by default. I just had the same problem on one of my servers. The solution for me was to add the following code in a place that gets read before any other pylab/matplotlib/pyplot import:

import matplotlib
# Force matplotlib to not use any Xwindows backend.
matplotlib.use('Agg')

The alternative is to set it in your .matplotlibrc

Error in Python IOError: [Errno 2] No such file or directory: 'data.csv'

It's looking for the file in the current directory.

First, go to that directory

cd /users/gcameron/Desktop/map

And then try to run it

python colorize_svg.py

Setting Icon for wpf application (VS 08)

You can try this also:

private void Page_Loaded_1(object sender, RoutedEventArgs e)
    {
        Uri iconUri = new Uri(@"C:\Apps\R&D\WPFNavigation\WPFNavigation\Images\airport.ico", UriKind.RelativeOrAbsolute);
        (this.Parent as Window).Icon = BitmapFrame.Create(iconUri);
    }

How do I view the SQLite database on an Android device?

Here are step-by-step instructions (mostly taken from a combination of the other answers). This works even on devices that are not rooted.

  1. Connect your device and launch the application in debug mode.

  2. You may want to use adb -d shell "run-as com.yourpackge.name ls /data/data/com.yourpackge.name/databases/" to see what the database filename is.

Notice: com.yourpackge.name is your application package name. You can get it from the manifest file.

  1. Copy the database file from your application folder to your SD card.

    adb -d shell "run-as com.yourpackge.name cat /data/data/com.yourpackge.name/databases/filename.sqlite > /sdcard/filename.sqlite"

Notice: filename.sqlite is your database name you used when you created the database

  1. Pull the database files to your machine:

    adb pull /sdcard/filename.sqlite

This will copy the database from the SD card to the place where your ADB exist.

  1. Install Firefox SQLite Manager: https://addons.mozilla.org/en-US/firefox/addon/sqlite-manager/

  2. Open Firefox SQLite Manager (Tools->SQLite Manager) and open your database file from step 3 above.

  3. Enjoy!

YouTube Autoplay not working

Remove the spaces before the autoplay=1:

src="https://www.youtube.com/embed/-SFcIUEvNOQ?autoplay=1&;enablejsapi=1"

How can I give an imageview click effect like a button on Android?

Thanks for the help on this thread. However, you missed one thing...you need to handle the ACTION_CANCEL as well. If you don't then you might not properly restore the alpha value of the ImageView in the event that a parent view in the view hierarchy intercepts a touch event (think a ScrollView wrapping you ImageView).

Here is a complete class that is based off the above class but takes care of the ACTION_CANCEL as well. It uses an ImageViewCompat helper class to abstract the differences in the pre-post JellyBean API.

public class ChangeAlphaOnPressedTouchListener implements OnTouchListener {

    private final float pressedAlpha;

    public ChangeAlphaOnPressedTouchListener(float pressedAlpha) {
        this.pressedAlpha = pressedAlpha;
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        ImageView iv = (ImageView) v;
        switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            ImageViewCompat.setAlpha(iv, pressedAlpha);
            break;

        case MotionEvent.ACTION_MOVE:
            if (isInsideViewBounds(v, event)) {
                ImageViewCompat.setAlpha(iv, pressedAlpha);
            } else {
                ImageViewCompat.setAlpha(iv, 1f);
            }
            break;
        case MotionEvent.ACTION_UP:
            ImageViewCompat.setAlpha(iv, 1f);
            break;
        case MotionEvent.ACTION_CANCEL:
            ImageViewCompat.setAlpha(iv, 1f);
        }
        return false;
    }

    private static boolean isInsideViewBounds(View v, MotionEvent event) {
        return event.getX() > 0 && event.getX() < v.getWidth() && event.getY() > 0
                && event.getY() < v.getHeight();
    }
}

Access iframe elements in JavaScript

You should access frames from window and not document

window.frames['myIFrame'].document.getElementById('myIFrameElemId')

Which sort algorithm works best on mostly sorted data?

Based on the highly scientific method of watching animated gifs I would say Insertion and Bubble sorts are good candidates.

Postgresql: error "must be owner of relation" when changing a owner object

Thanks to Mike's comment, I've re-read the doc and I've realised that my current user (i.e. userA that already has the create privilege) wasn't a direct/indirect member of the new owning role...

So the solution was quite simple - I've just done this grant:

grant userB to userA;

That's all folks ;-)


Update:

Another requirement is that the object has to be owned by user userA before altering it...

Get value of a merged cell of an excel from its cell address in vba

Even if it is really discouraged to use merge cells in Excel (use Center Across Selection for instance if needed), the cell that "contains" the value is the one on the top left (at least, that's a way to express it).

Hence, you can get the value of merged cells in range B4:B11 in several ways:

  • Range("B4").Value
  • Range("B4:B11").Cells(1).Value
  • Range("B4:B11").Cells(1,1).Value

You can also note that all the other cells have no value in them. While debugging, you can see that the value is empty.

Also note that Range("B4:B11").Value won't work (raises an execution error number 13 if you try to Debug.Print it) because it returns an array.

Setting Access-Control-Allow-Origin in ASP.Net MVC - simplest possible method

There are different ways we can pass the Access-Control-Expose-Headers.

  • As jgauffin has explained we can create a new attribute.
  • As LaundroMatt has explained we can add in the web.config file.
  • Another way is we can add code as below in the webApiconfig.cs file.

    config.EnableCors(new EnableCorsAttribute("", headers: "", methods: "*",exposedHeaders: "TestHeaderToExpose") { SupportsCredentials = true });

Or we can add below code in the Global.Asax file.

protected void Application_BeginRequest()
        {
            if (HttpContext.Current.Request.HttpMethod == "OPTIONS")
            {
                //These headers are handling the "pre-flight" OPTIONS call sent by the browser
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Methods", "GET, POST, OPTIONS");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Headers", "*");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Credentials", "true");
                HttpContext.Current.Response.AddHeader("Access-Control-Allow-Origin", "http://localhost:4200");
                HttpContext.Current.Response.AddHeader("Access-Control-Expose-Headers", "TestHeaderToExpose");
                HttpContext.Current.Response.End();
            }
        }

I have written it for the options. Please modify the same as per your need.

Happy Coding !!

Get string character by index - Java

if someone is strugling with kotlin, the code is:

var oldStr: String = "kotlin"
var firstChar: String = oldStr.elementAt(0).toString()
Log.d("firstChar", firstChar.toString())

this will return the char in position 1, in this case k remember, the index starts in position 0, so in this sample: kotlin would be k=position 0, o=position 1, t=position 2, l=position 3, i=position 4 and n=position 5

How to configure WAMP (localhost) to send email using Gmail?

I'm positive it would require SMTP authentication credentials as well.

Convert UIImage to NSData and convert back to UIImage in Swift?

To save as data:

From StoryBoard, if you want to save "image" data on the imageView of MainStoryBoard, following codes will work.

let image = UIImagePNGRepresentation(imageView.image!) as NSData?

To load "image" to imageView: Look at exclamation point "!", "?" closely whether that is quite same as this one.

imageView.image = UIImage(data: image as! Data)

"NSData" type is converted into "Data" type automatically during this process.

Using HTML5 file uploads with AJAX and jQuery

With jQuery (and without FormData API) you can use something like this:

function readFile(file){
   var loader = new FileReader();
   var def = $.Deferred(), promise = def.promise();

   //--- provide classic deferred interface
   loader.onload = function (e) { def.resolve(e.target.result); };
   loader.onprogress = loader.onloadstart = function (e) { def.notify(e); };
   loader.onerror = loader.onabort = function (e) { def.reject(e); };
   promise.abort = function () { return loader.abort.apply(loader, arguments); };

   loader.readAsBinaryString(file);

   return promise;
}

function upload(url, data){
    var def = $.Deferred(), promise = def.promise();
    var mul = buildMultipart(data);
    var req = $.ajax({
        url: url,
        data: mul.data,
        processData: false,
        type: "post",
        async: true,
        contentType: "multipart/form-data; boundary="+mul.bound,
        xhr: function() {
            var xhr = jQuery.ajaxSettings.xhr();
            if (xhr.upload) {

                xhr.upload.addEventListener('progress', function(event) {
                    var percent = 0;
                    var position = event.loaded || event.position; /*event.position is deprecated*/
                    var total = event.total;
                    if (event.lengthComputable) {
                        percent = Math.ceil(position / total * 100);
                        def.notify(percent);
                    }                    
                }, false);
            }
            return xhr;
        }
    });
    req.done(function(){ def.resolve.apply(def, arguments); })
       .fail(function(){ def.reject.apply(def, arguments); });

    promise.abort = function(){ return req.abort.apply(req, arguments); }

    return promise;
}

var buildMultipart = function(data){
    var key, crunks = [], bound = false;
    while (!bound) {
        bound = $.md5 ? $.md5(new Date().valueOf()) : (new Date().valueOf());
        for (key in data) if (~data[key].indexOf(bound)) { bound = false; continue; }
    }

    for (var key = 0, l = data.length; key < l; key++){
        if (typeof(data[key].value) !== "string") {
            crunks.push("--"+bound+"\r\n"+
                "Content-Disposition: form-data; name=\""+data[key].name+"\"; filename=\""+data[key].value[1]+"\"\r\n"+
                "Content-Type: application/octet-stream\r\n"+
                "Content-Transfer-Encoding: binary\r\n\r\n"+
                data[key].value[0]);
        }else{
            crunks.push("--"+bound+"\r\n"+
                "Content-Disposition: form-data; name=\""+data[key].name+"\"\r\n\r\n"+
                data[key].value);
        }
    }

    return {
        bound: bound,
        data: crunks.join("\r\n")+"\r\n--"+bound+"--"
    };
};

//----------
//---------- On submit form:
var form = $("form");
var $file = form.find("#file");
readFile($file[0].files[0]).done(function(fileData){
   var formData = form.find(":input:not('#file')").serializeArray();
   formData.file = [fileData, $file[0].files[0].name];
   upload(form.attr("action"), formData).done(function(){ alert("successfully uploaded!"); });
});

With FormData API you just have to add all fields of your form to FormData object and send it via $.ajax({ url: url, data: formData, processData: false, contentType: false, type:"POST"})

OWIN Startup Class Missing

My case? I had startup file, but it is excluded in the project. I just included it and the error left.

C# Validating input for textbox on winforms

With WinForms you can use the ErrorProvider in conjunction with the Validating event to handle the validation of user input. The Validating event provides the hook to perform the validation and ErrorProvider gives a nice consistent approach to providing the user with feedback on any error conditions.

http://msdn.microsoft.com/en-us/library/system.windows.forms.errorprovider.aspx

Loading a properties file from Java package

public class Test{  
  static {
    loadProperties();
}
   static Properties prop;
   private static void loadProperties() {
    prop = new Properties();
    InputStream in = Test.class
            .getResourceAsStream("test.properties");
    try {
        prop.load(in);
        in.close();
    } catch (IOException e) {
        e.printStackTrace();
    }

}

Letsencrypt add domain to existing certificate

You can replace the certificate by just running the certbot again with ./certbot-auto certonly

You will be prompted with this message if you try to generate a certificate for a domain that you have already covered by an existing certificate:

-------------------------------------------------------------------------------
You have an existing certificate that contains a portion of the domains you
requested (ref: /etc/letsencrypt/renewal/<domain>.conf)

It contains these names: <domain>

You requested these names for the new certificate: <domain>,
<the domain you want to add to the cert>.

Do you want to expand and replace this existing certificate with the new
certificate?
-------------------------------------------------------------------------------

Just chose Expand and replace it.

Deploy a project using Git push

You could conceivably set up a git hook that when say a commit is made to say the "stable" branch it will pull the changes and apply them to the PHP site. The big downside is you won't have much control if something goes wrong and it will add time to your testing - but you can get an idea of how much work will be involved when you merge say your trunk branch into the stable branch to know how many conflicts you may run into. It will be important to keep an eye on any files that are site specific (eg. configuration files) unless you solely intend to only run the one site.

Alternatively have you looked into pushing the change to the site instead?

For information on git hooks see the githooks documentation.

Why "net use * /delete" does not work but waits for confirmation in my PowerShell script?

Try this:

net use * /delete /y

The /y key makes it select Yes in prompt silently

JWT authentication for ASP.NET Web API

I think you should use some 3d party server to support the JWT token and there is no out of the box JWT support in WEB API 2.

However there is an OWIN project for supporting some format of signed token (not JWT). It works as a reduced OAuth protocol to provide just a simple form of authentication for a web site.

You can read more about it e.g. here.

It's rather long, but most parts are details with controllers and ASP.NET Identity that you might not need at all. Most important are

Step 9: Add support for OAuth Bearer Tokens Generation

Step 12: Testing the Back-end API

There you can read how to set up endpoint (e.g. "/token") that you can access from frontend (and details on the format of the request).

Other steps provide details on how to connect that endpoint to the database, etc. and you can chose the parts that you require.

Databound drop down list - initial value

To select a value from the dropdown use the index like this:

if we have the

<asp:DropDownList ID="DropDownList1" runat="server" AppendDataBoundItems="true"></asp:DropDownList>

you would use :

DropDownList1.Items[DropDownList1.SelectedIndex].Value

this would return the value for the selected index.

Equivalent of LIMIT and OFFSET for SQL Server?

Adding a slight variation on Aaronaught's solution, I typically parametrize page number (@PageNum) and page size (@PageSize). This way each page click event just sends in the requested page number along with a configurable page size:

begin
    with My_CTE  as
    (
         SELECT col1,
              ROW_NUMBER() OVER(ORDER BY col1) AS row_number
     FROM
          My_Table
     WHERE
          <<<whatever>>>
    )
    select * from My_CTE
            WHERE RowNum BETWEEN (@PageNum - 1) * (@PageSize + 1) 
                              AND @PageNum * @PageSize

end

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

I'll just try to answer the question but my examples very simple because I'm new at mvc. Hope this help somebody.

    [HttpPost]  ///This function is in my controller class
    public ActionResult Delete(string txtDelete)
    {
        int _id = Convert.ToInt32(txtDelete); // put your code           
    }

This code is in my controller's cshtml

  >   @using (Html.BeginForm("Delete", "LibraryManagement"))
 {
<button>Delete</button>
@Html.Label("Enter an ID number");
@Html.TextBox("txtDelete")  }  

Just make sure the textbox name and your controller's function input are the same name and type(string).This way, your function get the textbox input.

Android SDK installation doesn't find JDK

I spent a little over an hour trying just about every option presented. I eventually figured out that I had a lot of stale entries for software that I had uninstalled. I deleted all the registry nodes that had any stale data (pointed to the wrong directory). This included the

[HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\JavaSoft\Java Runtime Environment]

and

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment]

entries as a JRE included in the JDK.

I also got rid of all the JAVA entries in my environmental variables. I guess I blame it on bad uninstallers that do not clean up after themselves.

Chrome Fullscreen API

I made a simple wrapper for the Fullscreen API, called screenfull.js, to smooth out the prefix mess and fix some inconsistencies in the different implementations. Check out the demo to see how the Fullscreen API works.

Recommended reading:

Mongoose, Select a specific field with find

I found a really good option in mongoose that uses distinct returns array all of a specific field in document.

User.find({}).distinct('email').then((err, emails) => { // do something })

What is the difference between Google App Engine and Google Compute Engine?

Basic difference is that Google App Engine (GAE) is a Platform as a Service (PaaS) whereas Google Compute Engine (GCE) is an Infrastructure as a Service (IaaS).

To run your application in GAE you just need to write your code and deploy it into GAE, no other headache. Since GAE is fully scalable, it will automatically acquire more instances in case the traffic goes higher and decrease the instances when traffic decreases. You will be charged for the resources you really use, I mean, you will be billed for the Instance-Hours, Transferred Data, Storage etc your app really used. But the restriction is, you can create your application in only Python, PHP, Java, NodeJS, .NET, Ruby and **Go.

On the other hand, GCE provides you full infrastructure in the form of Virtual Machine. You have complete control over those VMs' environment and runtime as you can write or install any program there. Actually GCE is the way to use Google Data Centers virtually. In GCE you have to manually configure your infrastructure to handle scalability by using Load Balancer.

Both GAE and GCE are part of Google Cloud Platform.

Update: In March 2014 Google announced a new service under App Engine named Managed Virtual Machine. Managed VMs offers app engine applications a bit more flexibility over app platform, CPU and memory options. Like GCE you can create a custom runtime environment in these VMs for app engine application. Actually Managed VMs of App Engine blurs the frontier between IAAS and PAAS to some extent.

Creating SolidColorBrush from hex color value

Try this instead:

(SolidColorBrush)(new BrushConverter().ConvertFrom("#ffaacc"));

Switch statement: must default be the last case?

The case statements and the default statement can occur in any order in the switch statement. The default clause is an optional clause that is matched if none of the constants in the case statements can be matched.

Good Example :-

switch(5) {
  case 1:
    echo "1";
    break;
  case 2:
  default:
    echo "2, default";
    break;
  case 3;
    echo "3";
    break;
}


Outputs '2,default'

very useful if you want your cases to be presented in a logical order in the code (as in, not saying case 1, case 3, case 2/default) and your cases are very long so you do not want to repeat the entire case code at the bottom for the default

Best way to check if a URL is valid

Actually... filter_var($url, FILTER_VALIDATE_URL); doesn't work very well. When you type in a real url, it works but, it only checks for http:// so if you type something like "http://weirtgcyaurbatc", it will still say it's real.

How to take a first character from the string

"ABCDEFG".First returns "A"

Dim s as string

s = "Rajan"
s.First
'R

s = "Sajan"
s.First
'S

How do I implement Toastr JS?

Toastr is a very nice component, and you can show messages with theses commands:

// for success - green box
toastr.success('Success messages');

// for errors - red box
toastr.error('errors messages');

// for warning - orange box
toastr.warning('warning messages');

// for info - blue box
toastr.info('info messages');

If you want to provide a title on the toastr message, just add a second argument:

// for info - blue box
toastr.success('The process has been saved.', 'Success');

you also can change the default behaviour using something like this:

toastr.options.timeOut = 3000; // 3s

See more on the github of the project.

Edits

A sample of use:

$(document).ready(function() {

    // show when page load
    toastr.info('Page Loaded!');

    $('#linkButton').click(function() {
       // show when the button is clicked
       toastr.success('Click Button');

    });

});

and a html:

<a id='linkButton'>Show Message</a>

Integer.toString(int i) vs String.valueOf(int i)

The String class provides valueOf methods for all primitive types and Object type so I assume they are convenience methods that can all be accessed through the one class.

NB Profiling results

Average intToString = 5368ms, Average stringValueOf = 5689ms (for 100,000,000 operations)

public class StringIntTest {


    public static long intToString () {
        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 100000000; i++) {
            String j = Integer.toString(i);
        }
        long finishTime = System.currentTimeMillis();

        return finishTime - startTime;
    }

    public static long stringValueOf () {

        long startTime = System.currentTimeMillis();
        for (int i = 0; i < 100000000; i++) {
            String j = String.valueOf(i);
        }
        long finishTime = System.currentTimeMillis();

        return finishTime - startTime;
    }

    public static void main(String[] args) {
        long intToStringElapsed = 0;
        long stringValueOfElapsed = 0;
        for (int i = 0; i < 10; i++) {
            intToStringElapsed += intToString();
            stringValueOfElapsed+= stringValueOf();
        }
        System.out.println("Average intToString = "+ (intToStringElapsed /10));
        System.out.println("Average stringValueOf = " +(stringValueOfElapsed / 10));
    }
}

(Excel) Conditional Formatting based on Adjacent Cell Value

You need to take out the $ signs before the row numbers in the formula....and the row number used in the formula should correspond to the first row of data, so if you are applying this to the ("applies to") range $B$2:$B$5 it must be this formula

=$B2>$C2

by using that "relative" version rather than your "absolute" one Excel (implicitly) adjusts the formula for each row in the range, as if you were copying the formula down

How to include JavaScript file or library in Chrome console?

In the modern browsers you can use the fetch to download resource (Mozilla docs) and then eval to execute it.

For example to download Angular1 you need to type:

fetch('https://cdnjs.cloudflare.com/ajax/libs/angular.js/1.5.8/angular.min.js')
    .then(response => response.text())
    .then(text => eval(text))
    .then(() => { /* now you can use your library */ })

What's the safest way to iterate through the keys of a Perl hash?

A few miscellaneous thoughts on this topic:

  1. There is nothing unsafe about any of the hash iterators themselves. What is unsafe is modifying the keys of a hash while you're iterating over it. (It's perfectly safe to modify the values.) The only potential side-effect I can think of is that values returns aliases which means that modifying them will modify the contents of the hash. This is by design but may not be what you want in some circumstances.
  2. John's accepted answer is good with one exception: the documentation is clear that it is not safe to add keys while iterating over a hash. It may work for some data sets but will fail for others depending on the hash order.
  3. As already noted, it is safe to delete the last key returned by each. This is not true for keys as each is an iterator while keys returns a list.

How can getContentResolver() be called in Android?

This one worked for me getBaseContext();

Paging UICollectionView by cells, not screen

just override the method:

- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset {
    *targetContentOffset = scrollView.contentOffset; // set acceleration to 0.0
    float pageWidth = (float)self.articlesCollectionView.bounds.size.width;
    int minSpace = 10;

    int cellToSwipe = (scrollView.contentOffset.x)/(pageWidth + minSpace) + 0.5; // cell width + min spacing for lines
    if (cellToSwipe < 0) {
        cellToSwipe = 0;
    } else if (cellToSwipe >= self.articles.count) {
        cellToSwipe = self.articles.count - 1;
    }
    [self.articlesCollectionView scrollToItemAtIndexPath:[NSIndexPath indexPathForRow:cellToSwipe inSection:0] atScrollPosition:UICollectionViewScrollPositionLeft animated:YES];
}

SQL order string as number

This will handle negative numbers, fractions, string, everything:

ORDER BY ISNUMERIC(col) DESC, Try_Parse(col AS decimal(10,2)), col;

What is a smart pointer and when should I use one?

Here is the Link for similar answers : http://sickprogrammersarea.blogspot.in/2014/03/technical-interview-questions-on-c_6.html

A smart pointer is an object that acts, looks and feels like a normal pointer but offers more functionality. In C++, smart pointers are implemented as template classes that encapsulate a pointer and override standard pointer operators. They have a number of advantages over regular pointers. They are guaranteed to be initialized as either null pointers or pointers to a heap object. Indirection through a null pointer is checked. No delete is ever necessary. Objects are automatically freed when the last pointer to them has gone away. One significant problem with these smart pointers is that unlike regular pointers, they don't respect inheritance. Smart pointers are unattractive for polymorphic code. Given below is an example for the implementation of smart pointers.

Example:

template <class X>
class smart_pointer
{
          public:
               smart_pointer();                          // makes a null pointer
               smart_pointer(const X& x)            // makes pointer to copy of x

               X& operator *( );
               const X& operator*( ) const;
               X* operator->() const;

               smart_pointer(const smart_pointer <X> &);
               const smart_pointer <X> & operator =(const smart_pointer<X>&);
               ~smart_pointer();
          private:
               //...
};

This class implement a smart pointer to an object of type X. The object itself is located on the heap. Here is how to use it:

smart_pointer <employee> p= employee("Harris",1333);

Like other overloaded operators, p will behave like a regular pointer,

cout<<*p;
p->raise_salary(0.5);

notifyDataSetChanged not working on RecyclerView

In my case, force run #notifyDataSetChanged in main ui thread will fix

public void refresh() {
        clearSelection();
        // notifyDataSetChanged must run in main ui thread, if run in not ui thread, it will not update until manually scroll recyclerview
        ((Activity) ctx).runOnUiThread(new Runnable() {
            @Override
            public void run() {
                adapter.notifyDataSetChanged();
            }
        });
    }

Disable Logback in SpringBoot

It might help if you say what your preferred logger is exactly, and what you did to try and install it. Anyway, Spring Boot tries to work with whatever is in the classpath, so if you don't want logback, take it off the classpath. There are instructions for log4j in the docs, but the same thing would apply to other supported logging systems (anything slf4j, log4j or java util).

How to write text in ipython notebook?

Adding to Matt's answer above (as I don't have comment privileges yet), one mouse-free workflow would be:

Esc then m then Enter so that you gain focus again and can start typing.

Without the last Enter you would still be in Escape mode and would otherwise have to use your mouse to activate text input in the cell.

Another way would be to add a new cell, type out your markdown in "Code" mode and then change to markdown once you're done typing everything you need, thus obviating the need to refocus.

You can then move on to your next cells. :)

ORA-00054: resource busy and acquire with NOWAIT specified

Step 1:

select object_name, s.sid, s.serial#, p.spid 
from v$locked_object l, dba_objects o, v$session s, v$process p
where l.object_id = o.object_id and l.session_id = s.sid and s.paddr = p.addr;

Step 2:

alter system kill session 'sid,serial#'; --`sid` and `serial#` get from step 1

More info: http://www.oracle-base.com/articles/misc/killing-oracle-sessions.php

How to form tuple column from two columns in Pandas

Pandas has the itertuples method to do exactly this:

list(df[['lat', 'long']].itertuples(index=False, name=None))

background:none vs background:transparent what is the difference?

To complement the other answers: if you want to reset all background properties to their initial value (which includes background-color: transparent and background-image: none) without explicitly specifying any value such as transparent or none, you can do so by writing:

background: initial;

How to connect to LocalDb

I think you hit the same issue as discussed in this post. You forgot to escape your \ character.

Calculate days between two Dates in Java 8

Get number of days before Christmas from current day , try this

System.out.println(ChronoUnit.DAYS.between(LocalDate.now(),LocalDate.of(Year.now().getValue(), Month.DECEMBER, 25)));

How to post JSON to a server using C#?

This option is not mentioned:

using (var client = new HttpClient())
{
    client.BaseAddress = new Uri("http://localhost:9000/");
    client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

    var foo = new User
    {
        user = "Foo",
        password = "Baz"
    }

    await client.PostAsJsonAsync("users/add", foo);
}

Is there a better way to iterate over two lists, getting one element from each list for each iteration?

This post helped me with zip(). I know I'm a few years late, but I still want to contribute. This is in Python 3.

Note: in python 2.x, zip() returns a list of tuples; in Python 3.x, zip() returns an iterator. itertools.izip() in python 2.x == zip() in python 3.x

Since it looks like you're building a list of tuples, the following code is the most pythonic way of trying to accomplish what you are doing.

>>> lat = [1, 2, 3]
>>> long = [4, 5, 6]
>>> tuple_list = list(zip(lat, long))
>>> tuple_list
[(1, 4), (2, 5), (3, 6)]

Or, alternatively, you can use list comprehensions (or list comps) should you need more complicated operations. List comprehensions also run about as fast as map(), give or take a few nanoseconds, and are becoming the new norm for what is considered Pythonic versus map().

>>> lat = [1, 2, 3]
>>> long = [4, 5, 6]
>>> tuple_list = [(x,y) for x,y in zip(lat, long)]
>>> tuple_list
[(1, 4), (2, 5), (3, 6)]
>>> added_tuples = [x+y for x,y in zip(lat, long)]
>>> added_tuples
[5, 7, 9]

C#: Looping through lines of multiline string

You can use a StringReader to read a line at a time:

using (StringReader reader = new StringReader(input))
{
    string line = string.Empty;
    do
    {
        line = reader.ReadLine();
        if (line != null)
        {
            // do something with the line
        }

    } while (line != null);
}

Bootstrap4 adding scrollbar to div

      <div class="overflow-auto p-3 mb-3 mb-md-0 mr-md-3 bg-light" style="max-width: 260px; max-height: 100px;">
        <strong>Column 0 </strong><br>
        <strong>Column 1</strong><br>
        <strong>Column 2</strong><br>
        <strong>Column 3</strong><br>
        <strong>Column 4</strong><br>
        <strong>Column 5</strong><br>
        <strong>Column 6</strong><br>
        <strong>Column 7</strong><br>
        <strong>Column 8</strong><br>
        <strong>Column 9</strong><br>
        <strong>Column 10</strong><br>
        <strong>Column 11</strong><br>
        <strong>Column 12</strong><br>
        <strong>Column 13</strong><br>
      </div>
    </div>

TypeError: Router.use() requires middleware function but got a Object

You are missing router exports module and that is the reason why this error is present.

use module.exports = router; and that would work

Get statistics for each group (such as count, mean, etc) using pandas GroupBy?

We can easily do it by using groupby and count. But, we should remember to use reset_index().

df[['col1','col2','col3','col4']].groupby(['col1','col2']).count().\
reset_index()

Unit testing void methods?

it will have some effect on an object.... query for the result of the effect. If it has no visible effect its not worth unit testing!

Can I delete data from the iOS DeviceSupport directory?

Yes, you can delete data from iOS device support by the symbols of the operating system, one for each version for each architecture. It's used for debugging. If you don't need to support those devices any more, you can delete the directory without ill effect

How to read a value from the Windows registry

Here is some pseudo-code to retrieve the following:

  1. If a registry key exists
  2. What the default value is for that registry key
  3. What a string value is
  4. What a DWORD value is

Example code:

Include the library dependency: Advapi32.lib

HKEY hKey;
LONG lRes = RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SOFTWARE\\Perl", 0, KEY_READ, &hKey);
bool bExistsAndSuccess (lRes == ERROR_SUCCESS);
bool bDoesNotExistsSpecifically (lRes == ERROR_FILE_NOT_FOUND);
std::wstring strValueOfBinDir;
std::wstring strKeyDefaultValue;
GetStringRegKey(hKey, L"BinDir", strValueOfBinDir, L"bad");
GetStringRegKey(hKey, L"", strKeyDefaultValue, L"bad");

LONG GetDWORDRegKey(HKEY hKey, const std::wstring &strValueName, DWORD &nValue, DWORD nDefaultValue)
{
    nValue = nDefaultValue;
    DWORD dwBufferSize(sizeof(DWORD));
    DWORD nResult(0);
    LONG nError = ::RegQueryValueExW(hKey,
        strValueName.c_str(),
        0,
        NULL,
        reinterpret_cast<LPBYTE>(&nResult),
        &dwBufferSize);
    if (ERROR_SUCCESS == nError)
    {
        nValue = nResult;
    }
    return nError;
}


LONG GetBoolRegKey(HKEY hKey, const std::wstring &strValueName, bool &bValue, bool bDefaultValue)
{
    DWORD nDefValue((bDefaultValue) ? 1 : 0);
    DWORD nResult(nDefValue);
    LONG nError = GetDWORDRegKey(hKey, strValueName.c_str(), nResult, nDefValue);
    if (ERROR_SUCCESS == nError)
    {
        bValue = (nResult != 0) ? true : false;
    }
    return nError;
}


LONG GetStringRegKey(HKEY hKey, const std::wstring &strValueName, std::wstring &strValue, const std::wstring &strDefaultValue)
{
    strValue = strDefaultValue;
    WCHAR szBuffer[512];
    DWORD dwBufferSize = sizeof(szBuffer);
    ULONG nError;
    nError = RegQueryValueExW(hKey, strValueName.c_str(), 0, NULL, (LPBYTE)szBuffer, &dwBufferSize);
    if (ERROR_SUCCESS == nError)
    {
        strValue = szBuffer;
    }
    return nError;
}

Best practices to test protected methods with PHPUnit

You can indeed use __call() in a generic fashion to access protected methods. To be able to test this class

class Example {
    protected function getMessage() {
        return 'hello';
    }
}

you create a subclass in ExampleTest.php:

class ExampleExposed extends Example {
    public function __call($method, array $args = array()) {
        if (!method_exists($this, $method))
            throw new BadMethodCallException("method '$method' does not exist");
        return call_user_func_array(array($this, $method), $args);
    }
}

Note that the __call() method does not reference the class in any way so you can copy the above for each class with protected methods you want to test and just change the class declaration. You may be able to place this function in a common base class, but I haven't tried it.

Now the test case itself only differs in where you construct the object to be tested, swapping in ExampleExposed for Example.

class ExampleTest extends PHPUnit_Framework_TestCase {
    function testGetMessage() {
        $fixture = new ExampleExposed();
        self::assertEquals('hello', $fixture->getMessage());
    }
}

I believe PHP 5.3 allows you to use reflection to change the accessibility of methods directly, but I assume you'd have to do so for each method individually.

async at console app in C#?

As a quick and very scoped solution:

Task.Result

Both Task.Result and Task.Wait won't allow to improving scalability when used with I/O, as they will cause the calling thread to stay blocked waiting for the I/O to end.

When you call .Result on an incomplete Task, the thread executing the method has to sit and wait for the task to complete, which blocks the thread from doing any other useful work in the meantime. This negates the benefit of the asynchronous nature of the task.

notasync

Python 2.7.10 error "from urllib.request import urlopen" no module named request

from urllib.request import urlopen, Request

Should solve everything

Add MIME mapping in web.config for IIS Express

To solve the problem, double-click the "MIME Types" configuration option while having IIS root node selected in the left panel and click "Add..." link in the Actions panel on the right. This will bring up the following dialog. Add .woff file extension and specify "application/x-font-woff" as the corresponding MIME type:

enter image description here

Follow same for woff2 with application/x-font-woff2

Fixed Table Cell Width

table td 
{
  table-layout:fixed;
  width:20px;
  overflow:hidden;
  word-wrap:break-word;
}

How do I get started with Node.js

You can follow these tutorials to get started

Tutorials

Developer Sites

Videos

Screencasts

Books

Courses

Blogs

Podcasts

JavaScript resources

Node.js Modules

Other

Showing which files have changed between two revisions

You can also use a visual diff.

For example, if you are using Sourcetree, you can simply select any two commits in log view.

(I personally prefer using a GUI in most cases for this, and I'm posting this for those who may not be familiar with GUI options.)

html 5 audio tag width

For those looking for an inline example, here is one:

<audio controls style="width: 200px;">
   <source src="http://somewhere.mp3" type="audio/mpeg">
</audio>

It doesn't seem to respect a "height" setting, at least not awesomely. But you can always "customize" the controls but creating your own controls (instead of using the built-in ones) or using somebody's widget that similarly creates its own :)

Oracle DB: How can I write query ignoring case?

You can use either lower or upper function on both sides of the where condition

Get login username in java

System.getenv().get("USERNAME"); - works on windows !

In environment properties you have the information you need about computer and host! I am saying again! Works on WINDOWS !

How do I set the icon for my application in visual studio 2008?

The important thing is that the icon you want to be displayed as the application icon ( in the title bar and in the task bar ) must be the FIRST icon in the resource script file

The file is in the res folder and is named (applicationName).rc

/////////////////////////////////////////////////////////////////////////////
//
// Icon
//

// Icon with lowest ID value placed first to ensure application icon
// remains consistent on all systems.
(icon ID )          ICON                    "res\\filename.ico"

How to identify server IP address in PHP

If you are using PHP in bash shell you can use:

$server_name=exec('hostname');

Because $_SERVER[] SERVER_ADDR, HTTP_HOST and SERVER_NAME are not set.

How do you test a public/private DSA keypair?

The check can be made easier with diff:

diff <(ssh-keygen -y -f $private_key_file) $public_key_file

The only odd thing is that diff says nothing if the files are the same, so you'll only be told if the public and private don't match.

Set database from SINGLE USER mode to MULTI USER

  1. Tried everything didn't work
  2. Login to that server remotely as we gonna kill all connections
  3. run the below code more than once till it returns completed and no "killing process" test anymore
  4. reactivate it again using the code below the below code

use master GO declare @sql as varchar(20), @spid as int

select @spid = min(spid) from master..sysprocesses where dbid = db_id('DB_NAME') and spid != @@spid

while (@spid is not null) begin print 'Killing process ' + cast(@spid as varchar) + ' ...' set @sql = 'kill ' + cast(@spid as varchar) exec (@sql)

select 
    @spid = min(spid)  
from 
    master..sysprocesses  
where 
    dbid = db_id('DB_NAME') 
    and spid != @@spid end

then to bring it back alive

ALTER DATABASE DB_NAME SET MULTI_USER; GO

MySQL: #1075 - Incorrect table definition; autoincrement vs another key?

First create table without auto_increment,

CREATE TABLE `members`(
    `id` int(11) NOT NULL,
    `memberid` VARCHAR( 30 ) NOT NULL ,
    `Time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ,
    `firstname` VARCHAR( 50 ) NULL ,
    `lastname` VARCHAR( 50 ) NULL
    PRIMARY KEY (memberid) 
) ENGINE = MYISAM;

after set id as index,

ALTER TABLE `members` ADD INDEX(`id`);

after set id as auto_increment,

ALTER TABLE `members` CHANGE `id` `id` INT(11) NOT NULL AUTO_INCREMENT;

Or

CREATE TABLE IF NOT EXISTS `members` (
    `id` int(11) NOT NULL,
    `memberid` VARCHAR( 30 ) NOT NULL ,
    `Time` TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ,
    `firstname` VARCHAR( 50 ) NULL ,
    `lastname` VARCHAR( 50 ) NULL,
      PRIMARY KEY (`memberid`),
      KEY `id` (`id`)
) ENGINE=MYISAM DEFAULT CHARSET=utf8 AUTO_INCREMENT=1 ;

How to receive POST data in django

You should have access to the POST dictionary on the request object.

Set default host and port for ng serve in config file

We have two ways to change default port number in Angular.

First way is by CLI command:

ng serve --port 2400 --open

Second way is by configuration at the location:

ProjectName\node_modules\@angular-devkit\build-angular\src\dev-server\schema.json.

Make changes in schema.json file.

{
 "title": "Dev Server Target",
  "description": "Dev Server target options for Build Facade.",
  "type": "object",
  "properties": {
    "browserTarget": {
      "type": "string",
      "description": "Target to serve."
    },
    "port": {
      "type": "number",
      "description": "Port to listen on.",
      "default": 2400
    },

Creating a very simple 1 username/password login in php

<?php
session_start();
  mysql_connect('localhost','root','');
    mysql_select_db('database name goes here');
    $error_msg=NULL;
    //log out code
    if(isset($_REQUEST['logout'])){
                unset($_SESSION['user']);
                unset($_SESSION['username']);
                unset($_SESSION['id']);
                unset($_SESSION['role']);
        session_destroy();
    }
    //

    if(!empty($_POST['submit'])){
        if(empty($_POST['username']))
            $error_msg='please enter username';
        if(empty($_POST['password']))
            $error_msg='please enter password';
        if(empty($error_msg)){
            $sql="SELECT*FROM users WHERE username='%s' AND password='%s'";
            $sql=sprintf($sql,$_POST['username'],md5($_POST['password']));
            $records=mysql_query($sql) or die(mysql_error());

            if($record_new=mysql_fetch_array($records)){

                $_SESSION['user']=$record_new;
                $_SESSION['id']=$record_new['id'];
                $_SESSION['username']=$record_new['username'];
                $_SESSION['role']=$record_new['role'];
                header('location:index.php');
                $error_msg='welcome';
                exit();
            }else{
                $error_msg='invalid details';
            }
        }       
    }

?>

// replace the location with whatever page u want the user to visit when he/she log in

com.apple.WebKit.WebContent drops 113 error: Could not find specified service

Mine was different again. I was setting the user-agent like so:

    NSString *jScript = @"var meta = document.createElement('meta'); meta.setAttribute('name', 'viewport'); meta.setAttribute('content', 'width=device-width'); document.getElementsByTagName('head')[0].appendChild(meta);";
    WKUserScript *wkUScript = [[WKUserScript alloc] initWithSource:jScript injectionTime:WKUserScriptInjectionTimeAtDocumentEnd forMainFrameOnly:YES];

This was causing something on the web page to freak out and leak memory. Not sure why but removing this sorted the issue for me.

Java RegEx meta character (.) and ordinary dot?

If you want to end check whether your sentence ends with "." then you have to add [\.\]$ to the end of your pattern.

How to solve time out in phpmyadmin?

I was having the issue previously in XAMPP localhost with phpmyadmin version 4.2.11.

Increasing the timeout in php.ini didn't helped either.

Then I edited xampp\phpMyAdmin\libraries\config.default.php to change the value of $cfg['ExecTimeLimit'], which was 300 by default.

That solved my issue.

How to escape double quotes in JSON

It's showing the backslash because you're also escaping the backslash.

Aside from double quotes, you must also escape backslashes if you want to include one in your JSON quoted string. However if you intend to use a backslash in an escape sequence, obviously you shouldn't escape it.

What is PEP8's E128: continuation line under-indented for visual indent?

PEP-8 recommends you indent lines to the opening parentheses if you put anything on the first line, so it should either be indenting to the opening bracket:

urlpatterns = patterns('',
                       url(r'^$', listing, name='investment-listing'))

or not putting any arguments on the starting line, then indenting to a uniform level:

urlpatterns = patterns(
    '',
    url(r'^$', listing, name='investment-listing'),
)

urlpatterns = patterns(
    '', url(r'^$', listing, name='investment-listing'))

I suggest taking a read through PEP-8 - you can skim through a lot of it, and it's pretty easy to understand, unlike some of the more technical PEPs.

find all the name using mysql query which start with the letter 'a'

I would go for substr() functionality in MySql.

Basically, this function takes account of three parameters i.e. substr(str,pos,len)

http://www.w3resource.com/mysql/string-functions/mysql-substr-function.php

SELECT * FROM artists 
WHERE lower(substr(name,1,1)) in ('a','b','c');

Counter exit code 139 when running, but gdb make it through

exit code 139 (people say this means memory fragmentation)

No, it means that your program died with signal 11 (SIGSEGV on Linux and most other UNIXes), also known as segmentation fault.

Could anybody tell me why the run fails but debug doesn't?

Your program exhibits undefined behavior, and can do anything (that includes appearing to work correctly sometimes).

Your first step should be running this program under Valgrind, and fixing all errors it reports.

If after doing the above, the program still crashes, then you should let it dump core (ulimit -c unlimited; ./a.out) and then analyze that core dump with GDB: gdb ./a.out core; then use where command.

How do I change column default value in PostgreSQL?

If you want to remove the default value constraint, you can do:

ALTER TABLE <table> ALTER COLUMN <column> DROP DEFAULT;

Can you find all classes in a package using reflection?

It is very possible, but without additional libraries like Reflections it is hard...
It is hard because you haven't full instrument for get class name.
And, I take the code of my ClassFinder class:

package play.util;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;

/**
 * Created by LINKOR on 26.05.2017 in 15:12.
 * Date: 2017.05.26
 */
public class FileClassFinder {
private JarFile file;
private boolean trouble;
public FileClassFinder(String filePath) {
    try {
        file = new JarFile(filePath);
    } catch (IOException e) {
        trouble = true;
    }
}

public List<String> findClasses(String pkg) {
    ArrayList<String> classes = new ArrayList<>();
    Enumeration<JarEntry> entries = file.entries();
    while (entries.hasMoreElements()) {
        JarEntry cls = entries.nextElement();
        if (!cls.isDirectory()) {
            String fileName = cls.getName();
            String className = fileName.replaceAll("/",         ".").replaceAll(File.pathSeparator, ".").substring(0, fileName.lastIndexOf('.'));
            if (className.startsWith(pkg)) classes.add(className.substring(pkg.length() + 1));
        }
    }
    return classes;
}
}

How to edit a text file in my terminal

Open the file again using vi. and then press the insert button to begin editing it.

How to add Options Menu to Fragment in Android

Call the super method:

Java:

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setHasOptionsMenu(true);
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        // TODO Add your menu entries here
        super.onCreateOptionsMenu(menu, inflater);
    }

Kotlin:

    override fun void onCreate(savedInstanceState: Bundle) {
        super.onCreate(savedInstanceState)
        setHasOptionsMenu(true)
    }

    override fun onCreateOptionsMenu(menu: Menu, inflater: MenuInflater) {
        // TODO Add your menu entries here
        super.onCreateOptionsMenu(menu, inflater)
    }

Put log statements in the code to see if the method is not being called or if the menu is not being amended by your code.

Also ensure you are calling setHasOptionsMenu(boolean) in onCreate(Bundle) to notify the fragment that it should participate in options menu handling.

How to pass arguments to a Button command in Tkinter?

For posterity: you can also use classes to achieve something similar. For instance:

class Function_Wrapper():
    def __init__(self, x, y, z):
        self.x, self.y, self.z = x, y, z
    def func(self):
        return self.x + self.y + self.z # execute function

Button can then be simply created by:

instance1 = Function_Wrapper(x, y, z)
button1  = Button(master, text = "press", command = instance1.func)

This approach also allows you to change the function arguments by i.e. setting instance1.x = 3.

SSIS Text was truncated with status value 4

I've had this issue before, it is likely that the default column size for the file is incorrect. It will put a default size of 50 characters but the data you are working with is larger. In the advanced settings for your data file, adjust the column size from 50 to the table's column size.

How to Create Multiple Where Clause Query Using Laravel Eloquent?

We use this instruction to obtain users according to two conditions, type of user classification and user name.

Here we use two conditions for filtering as you type in addition to fetching user information from the profiles table to reduce the number of queries.

$users = $this->user->where([
                    ['name','LIKE','%'.$request->name.'%'],
                    ['trainers_id','=',$request->trainers_id]
                    ])->with('profiles')->paginate(10);

Logical operators for boolean indexing in Pandas

Logical operators for boolean indexing in Pandas

It's important to realize that you cannot use any of the Python logical operators (and, or or not) on pandas.Series or pandas.DataFrames (similarly you cannot use them on numpy.arrays with more than one element). The reason why you cannot use those is because they implicitly call bool on their operands which throws an Exception because these data structures decided that the boolean of an array is ambiguous:

>>> import numpy as np
>>> import pandas as pd
>>> arr = np.array([1,2,3])
>>> s = pd.Series([1,2,3])
>>> df = pd.DataFrame([1,2,3])
>>> bool(arr)
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()
>>> bool(s)
ValueError: The truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().
>>> bool(df)
ValueError: The truth value of a DataFrame is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all().

I did cover this more extensively in my answer to the "Truth value of a Series is ambiguous. Use a.empty, a.bool(), a.item(), a.any() or a.all()" Q+A.

NumPys logical functions

However NumPy provides element-wise operating equivalents to these operators as functions that can be used on numpy.array, pandas.Series, pandas.DataFrame, or any other (conforming) numpy.array subclass:

So, essentially, one should use (assuming df1 and df2 are pandas DataFrames):

np.logical_and(df1, df2)
np.logical_or(df1, df2)
np.logical_not(df1)
np.logical_xor(df1, df2)

Bitwise functions and bitwise operators for booleans

However in case you have boolean NumPy array, pandas Series, or pandas DataFrames you could also use the element-wise bitwise functions (for booleans they are - or at least should be - indistinguishable from the logical functions):

Typically the operators are used. However when combined with comparison operators one has to remember to wrap the comparison in parenthesis because the bitwise operators have a higher precedence than the comparison operators:

(df1 < 10) | (df2 > 10)  # instead of the wrong df1 < 10 | df2 > 10

This may be irritating because the Python logical operators have a lower precendence than the comparison operators so you normally write a < 10 and b > 10 (where a and b are for example simple integers) and don't need the parenthesis.

Differences between logical and bitwise operations (on non-booleans)

It is really important to stress that bit and logical operations are only equivalent for boolean NumPy arrays (and boolean Series & DataFrames). If these don't contain booleans then the operations will give different results. I'll include examples using NumPy arrays but the results will be similar for the pandas data structures:

>>> import numpy as np
>>> a1 = np.array([0, 0, 1, 1])
>>> a2 = np.array([0, 1, 0, 1])

>>> np.logical_and(a1, a2)
array([False, False, False,  True])
>>> np.bitwise_and(a1, a2)
array([0, 0, 0, 1], dtype=int32)

And since NumPy (and similarly pandas) does different things for boolean (Boolean or “mask” index arrays) and integer (Index arrays) indices the results of indexing will be also be different:

>>> a3 = np.array([1, 2, 3, 4])

>>> a3[np.logical_and(a1, a2)]
array([4])
>>> a3[np.bitwise_and(a1, a2)]
array([1, 1, 1, 2])

Summary table

Logical operator | NumPy logical function | NumPy bitwise function | Bitwise operator
-------------------------------------------------------------------------------------
       and       |  np.logical_and        | np.bitwise_and         |        &
-------------------------------------------------------------------------------------
       or        |  np.logical_or         | np.bitwise_or          |        |
-------------------------------------------------------------------------------------
                 |  np.logical_xor        | np.bitwise_xor         |        ^
-------------------------------------------------------------------------------------
       not       |  np.logical_not        | np.invert              |        ~

Where the logical operator does not work for NumPy arrays, pandas Series, and pandas DataFrames. The others work on these data structures (and plain Python objects) and work element-wise. However be careful with the bitwise invert on plain Python bools because the bool will be interpreted as integers in this context (for example ~False returns -1 and ~True returns -2).

Undefined reference to `pow' and `floor'

All answers above are incomplete, the problem here lies in linker ld rather than compiler collect2: ld returned 1 exit status. When you are compiling your fib.c to object:

$ gcc -c fib.c
$ nm fib.o
0000000000000028 T fibo
                 U floor
                 U _GLOBAL_OFFSET_TABLE_
0000000000000000 T main
                 U pow
                 U printf

Where nm lists symbols from object file. You can see that this was compiled without an error, but pow, floor, and printf functions have undefined references, now if I will try to link this to executable:

$ gcc fib.o
fib.o: In function `fibo':
fib.c:(.text+0x57): undefined reference to `pow'
fib.c:(.text+0x84): undefined reference to `floor'
collect2: error: ld returned 1 exit status

Im getting similar output you get. To solve that, I need to tell linker where to look for references to pow, and floor, for this purpose I will use linker -l flag with m which comes from libm.so library.

$ gcc fib.o -lm
$ nm a.out
0000000000201010 B __bss_start
0000000000201010 b completed.7697
                 w __cxa_finalize@@GLIBC_2.2.5
0000000000201000 D __data_start
0000000000201000 W data_start
0000000000000620 t deregister_tm_clones
00000000000006b0 t __do_global_dtors_aux
0000000000200da0 t 
__do_global_dtors_aux_fini_array_entry
0000000000201008 D __dso_handle
0000000000200da8 d _DYNAMIC
0000000000201010 D _edata
0000000000201018 B _end
0000000000000722 T fibo
0000000000000804 T _fini
                 U floor@@GLIBC_2.2.5
00000000000006f0 t frame_dummy
0000000000200d98 t __frame_dummy_init_array_entry
00000000000009a4 r __FRAME_END__
0000000000200fa8 d _GLOBAL_OFFSET_TABLE_
                 w __gmon_start__
000000000000083c r __GNU_EH_FRAME_HDR
0000000000000588 T _init
0000000000200da0 t __init_array_end
0000000000200d98 t __init_array_start
0000000000000810 R _IO_stdin_used
                 w _ITM_deregisterTMCloneTable
                 w _ITM_registerTMCloneTable
0000000000000800 T __libc_csu_fini
0000000000000790 T __libc_csu_init
                 U __libc_start_main@@GLIBC_2.2.5
00000000000006fa T main
                 U pow@@GLIBC_2.2.5
                 U printf@@GLIBC_2.2.5
0000000000000660 t register_tm_clones
00000000000005f0 T _start
0000000000201010 D __TMC_END__

You can now see, functions pow, floor are linked to GLIBC_2.2.5.

Parameters order is important too, unless your system is configured to use shared librares by default, my system is not, so when I issue:

$ gcc -lm fib.o
fib.o: In function `fibo':
fib.c:(.text+0x57): undefined reference to `pow'
fib.c:(.text+0x84): undefined reference to `floor'
collect2: error: ld returned 1 exit status

Note -lm flag before object file. So in conclusion, add -lm flag after all other flags, and parameters, to be sure.

PHP include relative path

While I appreciate you believe absolute paths is not an option, it is a better option than relative paths and updating the PHP include path.

Use absolute paths with an constant you can set based on environment.

if (is_production()) {
    define('ROOT_PATH', '/some/production/path');
}
else {
    define('ROOT_PATH', '/root');
}

include ROOT_PATH . '/connect.php';

As commented, ROOT_PATH could also be derived from the current path, $_SERVER['DOCUMENT_ROOT'], etc.

How to send/receive SOAP request and response using C#?

The urls are different.

  • http://localhost/AccountSvc/DataInquiry.asmx

vs.

  • /acctinqsvc/portfolioinquiry.asmx

Resolve this issue first, as if the web server cannot resolve the URL you are attempting to POST to, you won't even begin to process the actions described by your request.

You should only need to create the WebRequest to the ASMX root URL, ie: http://localhost/AccountSvc/DataInquiry.asmx, and specify the desired method/operation in the SOAPAction header.

The SOAPAction header values are different.

  • http://localhost/AccountSvc/DataInquiry.asmx/ + methodName

vs.

  • http://tempuri.org/GetMyName

You should be able to determine the correct SOAPAction by going to the correct ASMX URL and appending ?wsdl

There should be a <soap:operation> tag underneath the <wsdl:operation> tag that matches the operation you are attempting to execute, which appears to be GetMyName.

There is no XML declaration in the request body that includes your SOAP XML.

You specify text/xml in the ContentType of your HttpRequest and no charset. Perhaps these default to us-ascii, but there's no telling if you aren't specifying them!

The SoapUI created XML includes an XML declaration that specifies an encoding of utf-8, which also matches the Content-Type provided to the HTTP request which is: text/xml; charset=utf-8

Hope that helps!

Dialogs / AlertDialogs: How to "block execution" while dialog is up (.NET-style)

Ted, you don't want to do this, really :) The biggest reason is that if you block the UI thread while you are displaying a Dialog, you will block the thread that's in charge of drawing and handling the events of your Dialog. Which means your dialog will be unresponsive. You will also cause ANRs if the user takes more than a few seconds to click the dialog.

Erich's answer is exactly what you need. I know it's not what you want, but that doesn't matter. We've designed Android to prevent developers from writing synchronous dialogs so you don't really have much of a choice.

Very Long If Statement in Python

According to PEP8, long lines should be placed in parentheses. When using parentheses, the lines can be broken up without using backslashes. You should also try to put the line break after boolean operators.

Further to this, if you're using a code style check such as pycodestyle, the next logical line needs to have different indentation to your code block.

For example:

if (abcdefghijklmnopqrstuvwxyz > some_other_long_identifier and
        here_is_another_long_identifier != and_finally_another_long_name):
    # ... your code here ...
    pass

jQuery get mouse position within an element

I use this piece of code, its quite nice :)

    <script language="javascript" src="http://code.jquery.com/jquery-1.4.1.js" type="text/javascript"></script>
<script language="javascript">
$(document).ready(function(){
    $(".div_container").mousemove(function(e){
        var parentOffset = $(this).parent().offset();
        var relativeXPosition = (e.pageX - parentOffset.left); //offset -> method allows you to retrieve the current position of an element 'relative' to the document
        var relativeYPosition = (e.pageY - parentOffset.top);
        $("#header2").html("<p><strong>X-Position: </strong>"+relativeXPosition+" | <strong>Y-Position: </strong>"+relativeYPosition+"</p>")
    }).mouseout(function(){
        $("#header2").html("<p><strong>X-Position: </strong>"+relativeXPosition+" | <strong>Y-Position: </strong>"+relativeYPosition+"</p>")
    });
});
</script>

How to check if array element is null to avoid NullPointerException in Java

You have more going on than you said. I ran the following expanded test from your example:

public class test {

    public static void main(String[] args) {
        Object[][] someArray = new Object[5][];
        someArray[0] = new Object[10];
        someArray[1] = null;
        someArray[2] = new Object[1];
        someArray[3] = null;
        someArray[4] = new Object[5];

        for (int i=0; i<=someArray.length-1; i++) {
            if (someArray[i] != null) {
                System.out.println("not null");
            } else {
                System.out.println("null");
            }
        }
    }
}

and got the expected output:

$ /cygdrive/c/Program\ Files/Java/jdk1.6.0_03/bin/java -cp . test
not null
null
not null
null
not null

Are you possibly trying to check the lengths of someArray[index]?

How do I evenly add space between a label and the input field regardless of length of text?

You can always use the 'pre' tag inside the label, and just enter the blank spaces in it, So you can always add the same or different number of spaces you require

<form>
<label>First Name :<pre>Here just enter number of spaces you want to use(I mean using spacebar to enter blank spaces)</pre>
<input type="text"></label>
<label>Last Name :<pre>Now Enter enter number of spaces to match above number of 
spaces</pre>
<input type="text"></label>
</form>

Hope you like my answer, It's a simple and efficient hack

Get commit list between tags in git

To style the output to your preferred pretty format, see the man page for git-log.

Example:

git log --pretty=format:"%h; author: %cn; date: %ci; subject:%s" tagA...tagB

Combine two ActiveRecord::Relation objects

This is how I've "handled" it if you use pluck to get an identifier for each of the records, join the arrays together and then finally do a query for those joined ids:

  transaction_ids = @club.type_a_trans.pluck(:id) + @club.type_b_transactions.pluck(:id) + @club.type_c_transactions.pluck(:id)
  @transactions = Transaction.where(id: transaction_ids).limit(100)

React JS get current date

OPTION 1: if you want to make a common utility function then you can use this

export function getCurrentDate(separator=''){

let newDate = new Date()
let date = newDate.getDate();
let month = newDate.getMonth() + 1;
let year = newDate.getFullYear();

return `${year}${separator}${month<10?`0${month}`:`${month}`}${separator}${date}`
}

and use it by just importing it as

import {getCurrentDate} from './utils'
console.log(getCurrentDate())

OPTION 2: or define and use in a class directly

getCurrentDate(separator=''){

let newDate = new Date()
let date = newDate.getDate();
let month = newDate.getMonth() + 1;
let year = newDate.getFullYear();

return `${year}${separator}${month<10?`0${month}`:`${month}`}${separator}${date}`
}

what does "dead beef" mean?

It's a magic number used in various places because it also happens to be readable in English, making it stand out. There's a partial list on Wikipedia.

How do I run Selenium in Xvfb?

open a terminal and run this command xhost +. This commands needs to be run every time you restart your machine. If everything works fine may be you can add this to startup commands

Also make sure in your /etc/environment file there is a line

export DISPLAY=:0.0 

And then, run your tests to see if your issue is resolved.

All please note the comment from sardathrion below before using this.

What is the main difference between PATCH and PUT request?

put:
If I want to update my first name, then I send a put request:

{ "first": "Nazmul", "last": "hasan" } 

But here is a problem with using put request: When I want to send put request I have to send all two parameters that is first and last (whereas I only need to update first) so it is mandatory to send them all again with put request.

patch:
patch request, on the other hand, says: only specify the data which you need to update and it won't be affecting or changing other data.
So no need to send all values again. Do I only need to change first name? Well, It only suffices to specify first in patch request.

Select and display only duplicate records in MySQL

Try this query:

SELECT id, COUNT( payer_email ) `tot`
FROM paypal_ipn_orders
GROUP BY id
HAVING `tot` >1

Does it help?

Selenium IDE - Command to wait for 5 seconds

In Chrome, For "Selenium IDE", I was also struggling that it doesn't pause. It will pause, if you give as below:

  • Command: pause
  • Target: blank
  • Value: 10000

This will pause for 10 seconds.

Hide div by default and show it on click with bootstrap

Just add water style="display:none"; to the <div>

Fiddles I say: http://jsfiddle.net/krY56/13/

jQuery:

function toggler(divId) {
    $("#" + divId).toggle();
}

Preferred to have a CSS Class .hidden

.hidden {
     display:none;
}

Run Command Line & Command From VBS

Set oShell = CreateObject ("WScript.Shell") 
oShell.run "cmd.exe /C copy ""S:Claims\Sound.wav"" ""C:\WINDOWS\Media\Sound.wav"" "

How to vertically align label and input in Bootstrap 3?

None of these solutions worked for me. But I was able to get vertical centering by using <div class="form-row align-items-center"> for each form row, per the Bootstrap examples.

Java error: Comparison method violates its general contract

It might also be an OpenJDK bug... (not in this case but it is the same error)

If somebody like me stumbles upon this answer regarding the

java.lang.IllegalArgumentException: Comparison method violates its general contract!

then it might also be a bug in the Java-Version. I have a compareTo running since several years now in some applications. But suddenly it stopped working and throws the error after all compares were done (i compare 6 Attributes before returning "0").

Now I just found this Bugreport of OpenJDK:

Python TypeError: cannot convert the series to <class 'int'> when trying to do math on dataframe

Seems your initial data contains strings and not numbers. It would probably be best to ensure that the data is already of the required type up front.

However, you can convert strings to numbers like this:

pd.Series(['123', '42']).astype(float)

instead of float(series)

REST API using POST instead of GET

In REST, each HTTP verbs has its place and meaning.

For example,

  • GET is to get the 'resource(s)' that is pointed to in the URL.

  • POST is to instructure the backend to 'create' a resource of the 'type' pointed to in the URL. You can supplement the POST operation with parameters or additional data in the body of the POST call.

In you case, since you are interested in 'getting' the info using query, thus it should be a GET operation instead of a POST operation.

This wiki may help to further clarify things.

Hope this help!

How to make a phone call in android and come back to my activity when the call is done?

We had the same problem and managed to solve it by using a PhoneStateListener to identify when the call ends, but additionally we had to finish() the original activity before starting it again with startActivity, otherwise the call log would be in front of it.

How to grep for contents after pattern?

sed -n 's/^potato:[[:space:]]*//p' file.txt

One can think of Grep as a restricted Sed, or of Sed as a generalized Grep. In this case, Sed is one good, lightweight tool that does what you want -- though, of course, there exist several other reasonable ways to do it, too.

Timer function to provide time in nano seconds using C++

In general, for timing how long it takes to call a function, you want to do it many more times than just once. If you call your function only once and it takes a very short time to run, you still have the overhead of actually calling the timer functions and you don't know how long that takes.

For example, if you estimate your function might take 800 ns to run, call it in a loop ten million times (which will then take about 8 seconds). Divide the total time by ten million to get the time per call.

What are Maven goals and phases and what is their difference?

Goals are executed in phases which help determine the order goals get executed in. The best understanding of this is to look at the default Maven lifecycle bindings which shows which goals get run in which phases by default. The compile phase goals will always be executed before the test phase goals, which will always be executed before the package phase goals and so on.

Part of the confusion is exacerbated by the fact that when you execute Maven you can specify a goal or a phase. If you specify a phase then Maven will run all phases up to the phase you specified in order (e.g. if you specify package it will first run through the compile phase and then the test phase and finally the package phase) and for each phase it will run all goals attached to that phase.

When you create a plugin execution in your Maven build file and you only specify the goal then it will bind that goal to a given default phase. For example, the jaxb:xjc goal binds by default to the generate-resources phase. However, when you specify the execution you can also explicitly specify the phase for that goal as well.

If you specify a goal when you execute Maven then it will run that goal and only that goal. In other words, if you specify the jar:jar goal it will only run the jar:jar goal to package your code into a jar. If you have not previously run the compile goal or prepared your compiled code in some other way this may very likely fail.

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

EDIT: This only works on API 8+ as noted by some of the comments.

This is a late answer, but you can add an onShowListener to the AlertDialog where you can then override the onClickListener of the button.

final AlertDialog dialog = new AlertDialog.Builder(context)
        .setView(v)
        .setTitle(R.string.my_title)
        .setPositiveButton(android.R.string.ok, null) //Set to null. We override the onclick
        .setNegativeButton(android.R.string.cancel, null)
        .create();

dialog.setOnShowListener(new DialogInterface.OnShowListener() {

    @Override
    public void onShow(DialogInterface dialogInterface) {

        Button button = ((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE);
        button.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View view) {
                // TODO Do something

                //Dismiss once everything is OK.
                dialog.dismiss();
            }
        });
    }
});
dialog.show();

Autowiring two beans implementing same interface - how to set default bean to autowire?

What about @Primary?

Indicates that a bean should be given preference when multiple candidates are qualified to autowire a single-valued dependency. If exactly one 'primary' bean exists among the candidates, it will be the autowired value. This annotation is semantically equivalent to the <bean> element's primary attribute in Spring XML.

@Primary
public class HibernateDeviceDao implements DeviceDao

Or if you want your Jdbc version to be used by default:

<bean id="jdbcDeviceDao" primary="true" class="com.initech.service.dao.jdbc.JdbcDeviceDao">

@Primary is also great for integration testing when you can easily replace production bean with stubbed version by annotating it.

OnClick vs OnClientClick for an asp:CheckBox?

You can assign function to all checkboxes then ask for confirmation inside of it. If they choose yes, checkbox is allowed to be changed if no it remains unchanged.

In my case I am also using ASP .Net checkbox inside a repeater (or grid) with Autopostback="True" attribute, so on server side I need to compare the value submitted vs what's currently in db in order to know what confirmation value they chose and update db only if it was "yes".

$(document).ready(function () {
    $('input[type=checkbox]').click(function(){                
        var areYouSure = confirm('Are you sure you want make this change?');
        if (areYouSure) {
            $(this).prop('checked', this.checked);
        } else {
            $(this).prop('checked', !this.checked);
        }
    });
}); 


<asp:CheckBox ID="chk" AutoPostBack="true" onCheckedChanged="chk_SelectedIndexChanged" runat="server" Checked='<%#Eval("FinancialAid") %>' />

protected void chk_SelectedIndexChanged(Object sender, EventArgs e)
{
    using (myDataContext db = new myDataDataContext())
    {
        CheckBox chk = (CheckBox)sender;
        RepeaterItem row = (RepeaterItem) chk.NamingContainer;            
        var studentID = ((Label) row.FindControl("lblID")).Text;
        var z = (from b in db.StudentApplicants
        where b.StudentID == studentID
        select b).FirstOrDefault();                
        if(chk != null && chk.Checked != z.FinancialAid){
            z.FinancialAid = chk.Checked;                
            z.ModifiedDate = DateTime.Now;
            db.SubmitChanges();
            BindGrid();
        }
        gvData.DataBind();
    }
}

How to Make A Chevron Arrow Using CSS?

> itself is very wonderful arrow! Just prepend a div with it and style it.

_x000D_
_x000D_
div{_x000D_
  font-size:50px;_x000D_
}_x000D_
div::before{_x000D_
  content:">";_x000D_
  font: 50px 'Consolas';_x000D_
  font-weight:900;_x000D_
}
_x000D_
<div class="arrowed">Hatz!</div>
_x000D_
_x000D_
_x000D_

Find Java classes implementing an interface

If you were asking from the perspective of working this out with a running program then you need to look to the java.lang.* package. If you get a Class object, you can use the isAssignableFrom method to check if it is an interface of another Class.

There isn't a simple built in way of searching for these, tools like Eclipse build an index of this information.

If you don't have a specific list of Class objects to test you can look to the ClassLoader object, use the getPackages() method and build your own package hierarchy iterator.

Just a warning though that these methods and classes can be quite slow.

Java: Insert multiple rows into MySQL with PreparedStatement

If you can create your sql statement dynamically you can do following workaround:

String myArray[][] = { { "1-1", "1-2" }, { "2-1", "2-2" }, { "3-1", "3-2" } };

StringBuffer mySql = new StringBuffer("insert into MyTable (col1, col2) values (?, ?)");

for (int i = 0; i < myArray.length - 1; i++) {
    mySql.append(", (?, ?)");
}

myStatement = myConnection.prepareStatement(mySql.toString());

for (int i = 0; i < myArray.length; i++) {
    myStatement.setString(i, myArray[i][1]);
    myStatement.setString(i, myArray[i][2]);
}
myStatement.executeUpdate();

How do I calculate r-squared using Python and Numpy?

A very late reply, but just in case someone needs a ready function for this:

scipy.stats.linregress

i.e.

slope, intercept, r_value, p_value, std_err = scipy.stats.linregress(x, y)

as in @Adam Marples's answer.

Select rows with same id but different value in another column

Select A.ARIDNR,A.LIEFNR
from Table A
join Table B
on A.ARIDNR = B.ARIDNR
and A.LIEFNR<> B.LIEFNR
group by A.ARIDNR,A.LIEFNR

AJAX jQuery refresh div every 5 seconds

you can use this one.

<div id="test"></div>

you java script code should be like that.

setInterval(function(){
      $('#test').load('test.php');
 },5000);

System.BadImageFormatException An attempt was made to load a program with an incorrect format

If you use IIS, Go to the Application pool Select the one that your site uses and click Advance Settings Make sure that the Enable 32-Bit Applications is set to True

Round up double to 2 decimal places

if you give it 234.545332233 it will give you 234.54

let textData = Double(myTextField.text!)!
let text = String(format: "%.2f", arguments: [textData])
mylabel.text = text

How do I do a Date comparison in Javascript?

You can use the getTime() method on a Date object to get the timestamp (in milliseconds) relative to January 1, 1970. If you convert your two dates into integer timestamps, you can then compare the difference by subtracting them. The result will be in milliseconds so you just divide by 1000 for seconds, then 60 for minutes, etc.

Unescape HTML entities in Javascript?

Most answers given here have a huge disadvantage: if the string you are trying to convert isn't trusted then you will end up with a Cross-Site Scripting (XSS) vulnerability. For the function in the accepted answer, consider the following:

htmlDecode("<img src='dummy' onerror='alert(/xss/)'>");

The string here contains an unescaped HTML tag, so instead of decoding anything the htmlDecode function will actually run JavaScript code specified inside the string.

This can be avoided by using DOMParser which is supported in all modern browsers:

_x000D_
_x000D_
function htmlDecode(input) {_x000D_
  var doc = new DOMParser().parseFromString(input, "text/html");_x000D_
  return doc.documentElement.textContent;_x000D_
}_x000D_
_x000D_
console.log(  htmlDecode("&lt;img src='myimage.jpg'&gt;")  )    _x000D_
// "<img src='myimage.jpg'>"_x000D_
_x000D_
console.log(  htmlDecode("<img src='dummy' onerror='alert(/xss/)'>")  )  _x000D_
// ""
_x000D_
_x000D_
_x000D_

This function is guaranteed to not run any JavaScript code as a side-effect. Any HTML tags will be ignored, only text content will be returned.

Compatibility note: Parsing HTML with DOMParser requires at least Chrome 30, Firefox 12, Opera 17, Internet Explorer 10, Safari 7.1 or Microsoft Edge. So all browsers without support are way past their EOL and as of 2017 the only ones that can still be seen in the wild occasionally are older Internet Explorer and Safari versions (usually these still aren't numerous enough to bother).

How to print a number with commas as thousands separators in JavaScript

You could just use the printf-way, for example:

double number = 1234567;
System.out.printf("%,.2f" , number);

How to make an HTTP get request with parameters

You can also pass value directly via URL.

If you want to call method public static void calling(string name){....}

then you should call usingHttpWebRequest webrequest = (HttpWebRequest)WebRequest.Create("http://localhost:****/Report/calling?name=Priya); webrequest.Method = "GET"; webrequest.ContentType = "application/text";

Just make sure you are using ?Object = value in URL

The operation couldn’t be completed. (com.facebook.sdk error 2.) ios6

I had the same issue and took a whole day to figure out the problem. This error message by Facebook SDK is very vague. I had this problem due to openURL: method being overwritten in MyApplication. I removed the overwritten method and facebook login worked fine.

Simplest way to display current month and year like "Aug 2016" in PHP?

Here is a simple and more update format of getting the data:

   $now = new \DateTime('now');
   $month = $now->format('m');
   $year = $now->format('Y');

"The system cannot find the file specified" when running C++ program

For me, I didn't have my startup project set in Solution Explorer.

Go to Solution Explorer on the left of VS, right click your unit test project, and choose "set as startup project".

I had just ported my code to a new workspace, and forgot that when I opened the project in VS in the solution there, that I needed to re-set my startup project.

Store multiple values in single key in json

{
    "success": true,
    "data": {
        "BLR": {
            "origin": "JAI",
            "destination": "BLR",
            "price": 127,
            "transfers": 0,
            "airline": "LB",
            "flight_number": 655,
            "departure_at": "2017-06-03T18:20:00Z",
            "return_at": "2017-06-07T08:30:00Z",
            "expires_at": "2017-03-05T08:40:31Z"
        }
    }
};

File Not Found when running PHP with Nginx

in case it helps someone, my issue seems to be just because I was using a subfolder under my home directory, even though permissions seem correct and I don't have SELinux or anything like that. changing it to be under /var/www/something/something made it work.

(if I ever found the real cause, and remember this answer, I'll update it)

coercing to Unicode: need string or buffer, NoneType found when rendering in django admin

First, check that whatever you are returning via unicode is a String.

If it is not a string you can change it to a string like this (where self.id is an integer)

def __unicode__(self):
    return '%s' % self.id

following which, if it still doesn't work, restart your ./manage.py shell for the changes to take effect and try again. It should work.

Best Regards

Using IF..ELSE in UPDATE (SQL server 2005 and/or ACCESS 2007)

this should work

update table_name
  set column_b = case
                  when column_a = 1 then 'Y'
                  else null
                 end,
  set column_c = case
                  when column_a = 2 then 'Y'
                  else null
                 end,
  set column_d = case
                  when column_a = 3 then 'Y'
                  else null
                 end
where
 conditions

the question is why would you want to do that...you may want to rethink the data model. you can replace null with whatever you want.

Remove HTML Tags from an NSString on the iPhone

A quick and "dirty" (removes everything between < and >) solution, works with iOS >= 3.2:

-(NSString *) stringByStrippingHTML {
  NSRange r;
  NSString *s = [[self copy] autorelease];
  while ((r = [s rangeOfString:@"<[^>]+>" options:NSRegularExpressionSearch]).location != NSNotFound)
    s = [s stringByReplacingCharactersInRange:r withString:@""];
  return s;
}

I have this declared as a category os NSString.

Error on line 2 at column 1: Extra content at the end of the document

On each loop of the result set, you're appending a new root element to the document, creating an XML document like this:

<?xml version="1.0"?>
<mycatch>...</mycatch>
<mycatch>...</mycatch>
...

An XML document can only have one root element, which is why the error is stating there is "extra content". Create a single root element and add all the mycatch elements to that:

$root = $dom->createElement("root");
$dom->appendChild($root);
// ...
while ($row = @mysql_fetch_assoc($result)){
  $node = $dom->createElement("mycatch");
  $root->appendChild($node);

Which versions of SSL/TLS does System.Net.WebRequest support?

When using System.Net.WebRequest your application will negotiate with the server to determine the highest TLS version that both your application and the server support, and use this. You can see more details on how this works here:

http://en.wikipedia.org/wiki/Transport_Layer_Security#TLS_handshake

If the server doesn't support TLS it will fallback to SSL, therefore it could potentially fallback to SSL3. You can see all of the versions that .NET 4.5 supports here:

http://msdn.microsoft.com/en-us/library/system.security.authentication.sslprotocols(v=vs.110).aspx

In order to prevent your application being vulnerable to POODLE, you can disable SSL3 on the machine that your application is running on by following this explanation:

https://serverfault.com/questions/637207/on-iis-how-do-i-patch-the-ssl-3-0-poodle-vulnerability-cve-2014-3566

Query for array elements inside JSON type

Create a table with column as type json

CREATE TABLE friends ( id serial primary key, data jsonb);

Now let's insert json data

INSERT INTO friends(data) VALUES ('{"name": "Arya", "work": ["Improvements", "Office"], "available": true}');
INSERT INTO friends(data) VALUES ('{"name": "Tim Cook", "work": ["Cook", "ceo", "Play"], "uses": ["baseball", "laptop"], "available": false}');

Now let's make some queries to fetch data

select data->'name' from friends;
select data->'name' as name, data->'work' as work from friends;

You might have noticed that the results comes with inverted comma( " ) and brackets ([ ])

    name    |            work            
------------+----------------------------
 "Arya"     | ["Improvements", "Office"]
 "Tim Cook" | ["Cook", "ceo", "Play"]
(2 rows)

Now to retrieve only the values just use ->>

select data->>'name' as name, data->'work'->>0 as work from friends;
select data->>'name' as name, data->'work'->>0 as work from friends where data->>'name'='Arya';

Passing variables, creating instances, self, The mechanics and usage of classes: need explanation

The whole point of a class is that you create an instance, and that instance encapsulates a set of data. So it's wrong to say that your variables are global within the scope of the class: say rather that an instance holds attributes, and that instance can refer to its own attributes in any of its code (via self.whatever). Similarly, any other code given an instance can use that instance to access the instance's attributes - ie instance.whatever.

How do I restart my C# WinForm Application?

I had the same exact problem and I too had a requirement to prevent duplicate instances - I propose an alternative solution to the one HiredMind is proposing (which will work fine).

What I am doing is starting the new process with the processId of the old process (the one that triggers the restart) as a cmd line argument:

// Shut down the current app instance.
Application.Exit();

// Restart the app passing "/restart [processId]" as cmd line args
Process.Start(Application.ExecutablePath, "/restart" + Process.GetCurrentProcess().Id);

Then when the new app starts I first parse the cm line args and check if the restart flag is there with a processId, then wait for that process to Exit:

if (_isRestart)
{
   try
   {
      // get old process and wait UP TO 5 secs then give up!
      Process oldProcess = Process.GetProcessById(_restartProcessId);
      oldProcess.WaitForExit(5000);
   }
   catch (Exception ex)
   { 
      // the process did not exist - probably already closed!
      //TODO: --> LOG
   }
}

I am obviously not showing all the safety checks that I have in place etc.

Even if not ideal - I find this a valid alternative so that you don't have to have in place a separate app just to handle restart.

RegExp matching string not starting with my

^(?!my)\w+$

should work.

It first ensures that it's not possible to match my at the start of the string, and then matches alphanumeric characters until the end of the string. Whitespace anywhere in the string will cause the regex to fail. Depending on your input you might want to either strip whitespace in the front and back of the string before passing it to the regex, or use add optional whitespace matchers to the regex like ^\s*(?!my)(\w+)\s*$. In this case, backreference 1 will contain the name of the variable.

And if you need to ensure that your variable name starts with a certain group of characters, say [A-Za-z_], use

^(?!my)[A-Za-z_]\w*$

Note the change from + to *.

What is an Android PendingIntent?

What is an Intent?

An Intent is a specific command in Android that allows you to send a command to the Android OS to do something specific. Think of it as an action that needs to take place. There are many actions that can be done such as sending an email, or attaching a photo to an email, or even launching an application. The logical workflow of creating an intent is usually as follows: a. Create the Intent b. Add Intent options -> Ex. what type of intent we are sending to the OS or any attributes associated with that intent, such as a text string or something being passed along with the intent c. RUN the Intent

Real-Life Example: Let's say I wake up in the morning and I "INTEND" to go to the washroom. I will first have to THINK about going to the washroom, but that DOESN'T really gets me to the washroom. I will then have to tell my brain to get out of bed first, then walk to the washroom, and then release, then go and wash my hands, then go and wipe my hands. Once I know where I'm going I SEND the command to begin and my body takes action.

What is Pending Intents?

Continuing from the real-life example, let's say I want to take a shower but I want to shower AFTER I brush my teeth and eat breakfast. So I know I won't be showering until at least 30-40 minutes. I still have in my head that I need to prepare my clothes, and then walk up the stairs back to the bathroom, then undress and then shower. However, this will not happen until 30-40 minutes have passed. I now have a PENDING intent to shower. It is PENDING for 30-40 minutes.

That is pretty much the difference between a Pending Intent and a Regular Intent. Regular Intents can be created without a Pending Intent, however, in order to create a Pending Intent you need to have a Regular Intent setup first.

How to listen to the window scroll event in a VueJS component?

Actually I found a solution. I add an event listener on the scroll event when the component is created and remove the event listener when the component is destroyed.

export default {
  created () {
    window.addEventListener('scroll', this.handleScroll);
  },
  destroyed () {
    window.removeEventListener('scroll', this.handleScroll);
  },
  methods: {
    handleScroll (event) {
      // Any code to be executed when the window is scrolled
    }
  }
}

Hope this helps!

Accessing attributes from an AngularJS directive

See section Attributes from documentation on directives.

observing interpolated attributes: Use $observe to observe the value changes of attributes that contain interpolation (e.g. src="{{bar}}"). Not only is this very efficient but it's also the only way to easily get the actual value because during the linking phase the interpolation hasn't been evaluated yet and so the value is at this time set to undefined.

Android notification is not showing

You were missing the small icon. I did the same mistake and the above step resolved it.

As per the official documentation: A Notification object must contain the following:

  1. A small icon, set by setSmallIcon()

  2. A title, set by setContentTitle()

  3. Detail text, set by setContentText()

  4. On Android 8.0 (API level 26) and higher, a valid notification channel ID, set by setChannelId() or provided in the NotificationCompat.Builder constructor when creating a channel.

See http://developer.android.com/guide/topics/ui/notifiers/notifications.html

"Cannot allocate an object of abstract type" error

In C++ a class with at least one pure virtual function is called abstract class. You can not create objects of that class, but may only have pointers or references to it.

If you are deriving from an abstract class, then make sure you override and define all pure virtual functions for your class.

From your snippet Your class AliceUniversity seems to be an abstract class. It needs to override and define all the pure virtual functions of the classes Graduate and UniversityGraduate.

Pure virtual functions are the ones with = 0; at the end of declaration.

Example: virtual void doSomething() = 0;

For a specific answer, you will need to post the definition of the class for which you get the error and the classes from which that class is deriving.

What's the fastest way to convert String to Number in JavaScript?

A fast way to convert strings to an integer is to use a bitwise or, like so:

x | 0

While it depends on how it is implemented, in theory it should be relatively fast (at least as fast as +x) since it will first cast x to a number and then perform a very efficient or.

How do I get a substring of a string in Python?

You've got it right there except for "end". It's called slice notation. Your example should read:

new_sub_string = myString[2:]

If you leave out the second parameter it is implicitly the end of the string.

SQL Server Management Studio – tips for improving the TSQL coding process

Use Object Explorer Details instead of object explorer for viewing your tables, this way you can press a letter and have it go to the first table with that letter prefix.

Entity Framework Timeouts

Adding the following to my stored procedure, solved the time out error by me:

SET NOCOUNT ON;
SET ARITHABORT ON;

Select the first 10 rows - Laravel Eloquent

First you can use a Paginator. This is as simple as:

$allUsers = User::paginate(15);

$someUsers = User::where('votes', '>', 100)->paginate(15);

The variables will contain an instance of Paginator class. all of your data will be stored under data key.

Or you can do something like:

Old versions Laravel.

Model::all()->take(10)->get();

Newer version Laravel.

Model::all()->take(10);

For more reading consider these links:

Could not load file or assembly System.Net.Http, Version=4.0.0.0 with ASP.NET (MVC 4) Web API OData Prerelease

After modifying the References in the Web.config file as mentioned above, we resolved the references.

I was facing similar issue.

For us we have reference Microsoft.Data.Edm.dll and OData.dll and other assemblies from Program Files:

C:\Program Files (x86)\Microsoft WCF Data Services\5.0
                          \bin\.NETFramework\Microsoft.Data.Edm.dll

and

C:\Program Files (x86)\Microsoft WCF Data Services\5.0
                        \bin\.NETFramework\Microsoft.Data.OData.dll

and version was 5.6.4.

Once I change the reference of both assemblies to C:\....Project\packages\Microsoft.Data.Edm.5.6.0 , the issue was resolved

How to replace all occurrences of a string in Javascript?

Use a regular expression:

str.replace(/abc/g, '');

HTML5 placeholder css padding

I've created a fiddle using your screenshot as a background image and stripping out the extra mark-up, and it seems to work fine

http://jsfiddle.net/fLdQG/2/ (webkit browser required)

Does this work for you? If not, can you update the fiddle with your exact mark-up and CSS?

How to keep :active css style after click a button

In the Divi Theme Documentation, it says that the theme comes with access to 'ePanel' which also has an 'Integration' section.

You should be able to add this code:

<script>
 $( ".et-pb-icon" ).click(function() {
 $( this ).toggleClass( "active" );
 });
</script>

into the the box that says 'Add code to the head of your blog' under the 'Integration' tab, which should get the jQuery working.

Then, you should be able to style your class to what ever you need.

Passing capturing lambda as function pointer

A shortcut for using a lambda with as a C function pointer is this:

"auto fun = +[](){}"

Using Curl as exmample (curl debug info)

auto callback = +[](CURL* handle, curl_infotype type, char* data, size_t size, void*){ //add code here :-) };
curl_easy_setopt(curlHande, CURLOPT_VERBOSE, 1L);
curl_easy_setopt(curlHande,CURLOPT_DEBUGFUNCTION,callback);

Access XAMPP Localhost from Internet

I know this very old but for future's sake:

I also used a dynamic dns provider. Wanted to test the website (IIS) BEHIND my (home) router. So i thought i use something like this:

my.dynamic.dnss.ip:8080 (because my router's port 80 was used to admin it).

So this seemed to be the only solution.
But: Paypal seemed to not like port 8080: only port 80 and 443 are allowed (don't know why!!)

NSOperation vs Grand Central Dispatch

GCD is a low-level C-based API.
NSOperation and NSOperationQueue are Objective-C classes.
NSOperationQueue is objective C wrapper over GCD. If you are using NSOperation, then you are implicitly using Grand Central Dispatch.

GCD advantage over NSOperation:
i. implementation
For GCD implementation is very light-weight
NSOperationQueue is complex and heavy-weight

NSOperation advantages over GCD:

i. Control On Operation
you can Pause, Cancel, Resume an NSOperation

ii. Dependencies
you can set up a dependency between two NSOperations
operation will not started until all of its dependencies return true for finished.

iii. State of Operation
can monitor the state of an operation or operation queue. ready ,executing or finished

iv. Max Number of Operation
you can specify the maximum number of queued operations that can run simultaneously

When to Go for GCD or NSOperation
when you want more control over queue (all above mentioned) use NSOperation and for simple cases where you want less overhead (you just want to do some work "into the background" with very little additional work) use GCD

ref:
https://cocoacasts.com/choosing-between-nsoperation-and-grand-central-dispatch/ http://iosinfopot.blogspot.in/2015/08/nsthread-vs-gcd-vs-nsoperationqueue.html http://nshipster.com/nsoperation/

What's a .sh file?

What is a file with extension .sh?

It is a Bourne shell script. They are used in many variations of UNIX-like operating systems. They have no "language" and are interpreted by your shell (interpreter of terminal commands) or if the first line is in the form

#!/path/to/interpreter

they will use that particular interpreter. Your file has the first line:

#!/bin/bash

and that means that it uses Bourne Again Shell, so called bash. It is for all practical purposes a replacement for good old sh.

Depending upon the interpreter you will have different language in which the file is written.

Keep in mind, that in UNIX world, it is not the extension of the file that determines what the file is (see How to execute a shell script).

If you come from the world of DOS/Windows, you will be familiar with files that have .bat or .cmd extensions (batch files). They are not similar in content, but are akin in design.

How to execute a shell script

Unlike some silly operating systems, *nix does not rely exclusively on extensions to determine what to do with a file. Permissions are also used. This means that if you attempt to run the shell script after downloading it, it will be the same as trying to "run" any text file. The ".sh" extension is there only for your convenience to recognize that file.

You will need to make the file executable. Let's assume that you have downloaded your file as file.sh, you can then run in your terminal:

chmod +x file.sh

chmod is a command for changing file's permissions, +x sets execute permissions (in this case for everybody) and finally you have your file name.

You can also do it in GUI. Most of the time you can right click on the file and select properties, in XUbuntu the permissions options look like this:

File permissions in XUbuntu

If you do not wish to change the permissions. You can also force the shell to run the command. In the terminal you can run:

bash file.sh

The shell should be the same as in the first line of your script.

How safe is it?

You may find it weird that you must perform another task manually in order to execute a file. But this is partially because of strong need for security.

Basically when you download and run a bash script, it is the same thing as somebody telling you "run all these commands in sequence on your computer, I promise that the results will be good and safe". Ask yourself if you trust the party that has supplied this file, ask yourself if you are sure that have downloaded the file from the same place as you thought, maybe even have a glance inside to see if something looks out of place (although that requires that you know something about *nix commands and bash programming).

Unfortunately apart from the warning above I cannot give a step-by-step description of what you should do to prevent evil things from happening with your computer; so just keep in mind that any time you get and run an executable file from someone you're actually saying, "Sure, you can use my computer to do something".

anaconda update all possible packages?

To answer more precisely to the question:

conda (which is conda for miniconda as for Anaconda) updates all but ONLY within a specific version of a package -> major and minor. That's the paradigm.

In the documentation you will find "NOTE: Conda updates to the highest version in its series, so Python 2.7 updates to the highest available in the 2.x series and 3.6 updates to the highest available in the 3.x series." doc

If Wang does not gives a reproducible example, one can only assist. e.g. is it really the virtual environment he wants to update or could Wang get what he/she wants with

conda update -n ENVIRONMENT --all

*PLEASE read the docs before executing "update --all"! This does not lead to an update of all packages by nature. Because conda tries to resolve the relationship of dependencies between all packages in your environment, this can lead to DOWNGRADED packages without warnings.


If you only want to update almost all, you can create a pin file

echo "conda ==4.0.0" >> ~/miniconda3/envs/py35/conda-meta/pinned
echo "numpy 1.7.*" >> ~/miniconda3/envs/py35/conda-meta/pinned

before running the update. conda issues not pinned

If later on you want to ignore the file in your env for an update, you can do:

conda update --all --no-pin

You should not do update --all. If you need it nevertheless you are saver to test this in a cloned environment.

First step should always be to backup your current specification:

conda list -n py35 --explicit 

(but even so there is not always a link to the source available - like for jupyterlab extensions)

Next you can clone and update:

conda create -n py356 --clone py35

conda activate py356
conda config --set pip_interop_enabled True # for conda>=4.6
conda update --all

conda config


update:

Because the idea of conda is nice but it is not working out very well for complex environments I personally prefer the combination of nix-shell (or lorri) and poetry [as superior pip/conda .-)] (intro poetry2nix).

Alternatively you can use nix and mach-nix (where you only need you requirements file. It resolves and builds environments best.


On Linux / macOS you could use nix like

nix-env -iA nixpkgs.python37

to enter an environment that has e.g. in this case Python3.7 (for sure you can change the version)

or as a very good Python (advanced) environment you can use mach-nix (with nix) like

mach-nix env ./env -r requirements.txt 

(which even supports conda [but currently in beta])

or via api like

nix-shell -p nixFlakes --run "nix run github:davhau/mach-nix#with.ipython.pandas.seaborn.bokeh.scikit-learn "

Finally if you really need to work with packages that are not compatible due to its dependencies, it is possible with technologies like NixOS/nix-pkgs.

mysql count group by having

Maybe

SELECT count(*) FROM (
    SELECT COUNT(*) FROM Movies GROUP BY ID HAVING count(Genre) = 4
) AS the_count_total

although that would not be the sum of all the movies, just how many have 4 genre's.

So maybe you want

SELECT sum(
    SELECT COUNT(*) FROM Movies GROUP BY ID having Count(Genre) = 4
) as the_sum_total

Can we open pdf file using UIWebView on iOS?

Swift 4

     let webView = UIWebView(frame: view.bounds)
    let targetURL = Bundle.main.url(forResource: "sampleFileName", withExtension: "pdf")
    let request = URLRequest(url: targetURL!)
    webView.loadRequest(request)
    view.addSubview(webView)

How do I fit an image (img) inside a div and keep the aspect ratio?

Use max-height:100%; max-width:100%; for the image inside the div.