Programs & Examples On #Lightbox2

Lightbox 2 is a JQuery-script developed by Lokesh Dhakar used to display images in an overlaying box. It can also be used to make galleries and can be found at www.LokeshDhakar.com/projects/lightbox2

UnicodeEncodeError: 'charmap' codec can't encode characters

In Python 3.7, and running Windows 10 this worked (I am not sure whether it will work on other platforms and/or other versions of Python)

Replacing this line:

with open('filename', 'w') as f:

With this:

with open('filename', 'w', encoding='utf-8') as f:

The reason why it is working is because the encoding is changed to UTF-8 when using the file, so characters in UTF-8 are able to be converted to text, instead of returning an error when it encounters a UTF-8 character that is not suppord by the current encoding.

How do I add records to a DataGridView in VB.Net?

I think you should build a dataset/datatable in code and bind the grid to that.

Java GC (Allocation Failure)

"Allocation Failure" is cause of GC to kick is not correct. It is an outcome of GC operation.

GC kicks in when there is no space to allocate( depending on region minor or major GC is performed). Once GC is performed if space is freed good enough, but if there is not enough size it fails. Allocation Failure is one such failure. Below document have good explanation https://docs.oracle.com/javase/8/docs/technotes/guides/vm/gctuning/g1_gc.html

What's the difference between F5 refresh and Shift+F5 in Google Chrome browser?

Reload the current page:
F5
or
CTRL + R


Reload the current page, ignoring cached content (i.e. JavaScript files, images, etc.):
SHIFT + F5
or
CTRL + F5
or
CTRL + SHIFT + R

Why does overflow:hidden not work in a <td>?

I've just had a similar problem, and had to use the <div> inside the <td> at first (John MacIntyre's solution didn't work for me for various reasons).

Note though that <td><div>...</div></td> isn't valid placement for a div so instead I'm using a <span> with display:block; set. It validates fine now and works.

How do you get git to always pull from a specific branch?

There is also a way of configuring Git so, it always pulls and pushes the equivalent remote branch to the branch currently checked out to the working copy. It's called a tracking branch which git ready recommends setting by default.

For the next repository above the present working directory:

git config branch.autosetupmerge true

For all Git repositories, that are not configured otherwise:

git config --global branch.autosetupmerge true

Kind of magic, IMHO but this might help in cases where the specific branch is always the current branch.

When you have branch.autosetupmerge set to true and checkout a branch for the first time, Git will tell you about tracking the corresponding remote branch:

(master)$ git checkout gh-pages
Branch gh-pages set up to track remote branch gh-pages from origin.
Switched to a new branch 'gh-pages'

Git will then push to that corresponding branch automatically:

(gh-pages)$ git push
Counting objects: 8, done.
Delta compression using up to 2 threads.
Compressing objects: 100% (6/6), done.
Writing objects: 100% (6/6), 1003 bytes, done.
Total 6 (delta 2), reused 0 (delta 0)
To [email protected]:bigben87/webbit.git
   1bf578c..268fb60  gh-pages -> gh-pages

Python: json.loads returns items prefixing with 'u'

Those 'u' characters being appended to an object signifies that the object is encoded in "unicode".

If you want to remove those 'u' chars from your object you can do this:

import json, ast
jdata = ast.literal_eval(json.dumps(jdata)) # Removing uni-code chars

Let's checkout from python shell

>>> import json, ast
>>> jdata = [{u'i': u'imap.gmail.com', u'p': u'aaaa'}, {u'i': u'333imap.com', u'p': u'bbbb'}]
>>> jdata = ast.literal_eval(json.dumps(jdata))
>>> jdata
[{'i': 'imap.gmail.com', 'p': 'aaaa'}, {'i': '333imap.com', 'p': 'bbbb'}]

Unable to load config info from /usr/local/ssl/openssl.cnf on Windows

With the GnuWin32 tools I found the openssl.cnf under C:\gnuwin32\share

set OPENSSL_CONF=C:\gnuwin32\share\openssl.cnf

Open a new tab on button click in AngularJS

You can do this all within your controller by using the $window service here. $window is a wrapper around the global browser object window.

To make this work inject $window into you controller as follows

.controller('exampleCtrl', ['$scope', '$window',
    function($scope, $window) {
        $scope.redirectToGoogle = function(){
            $window.open('https://www.google.com', '_blank');
        };
    }
]);

this works well when redirecting to dynamic routes

Showing which files have changed between two revisions

There are plenty of answers here, but I wanted to add something that I commonly use. IF you are in one of the branches that you would like to compare I typically do one of the following. For the sake of this answer we will say that we are in our secondary branch. Depending on what view you need at the time will depend on which you choose, but most of the time I'm using the second option of the two. The first option may be handy if you are trying to revert back to an original copy -- either way, both get the job done!

This will compare master to the branch that we are in (which is secondary) and the original code will be the added lines and the new code will be considered the removed lines

git diff ..master

OR

This will also compare master to the branch that we are in (which is secondary) and the original code will be the old lines and the new code will be the new lines

git diff master..

Printing Exception Message in java

The output looks correct to me:

Invalid JavaScript code: sun.org.mozilla.javascript.internal.EvaluatorException: missing } after property list (<Unknown source>) in <Unknown source>; at line number 1

I think Invalid Javascript code: .. is the start of the exception message.

Normally the stacktrace isn't returned with the message:

try {
    throw new RuntimeException("hu?\ntrace-line1\ntrace-line2");
} catch (Exception e) {
    System.out.println(e.getMessage()); // prints "hu?"
}

So maybe the code you are calling catches an exception and rethrows a ScriptException. In this case maybe e.getCause().getMessage() can help you.

WPF Databinding: How do I access the "parent" data context?

This will also work:

<Hyperlink Command="{Binding RelativeSource={RelativeSource AncestorType=ItemsControl},
                             Path=DataContext.AllowItemCommand}" />

ListView will inherit its DataContext from Window, so it's available at this point, too.
And since ListView, just like similar controls (e. g. Gridview, ListBox, etc.), is a subclass of ItemsControl, the Binding for such controls will work perfectly.

Git merge errors

git commit -m "Merged master fixed conflict."

How to use OUTPUT parameter in Stored Procedure

The SQL in your SP is wrong. You probably want

Select @code = RecItemCode from Receipt where RecTransaction = @id

In your statement, you are not setting @code, you are trying to use it for the value of RecItemCode. This would explain your NullReferenceException when you try to use the output parameter, because a value is never assigned to it and you're getting a default null.

The other issue is that your SQL statement if rewritten as

Select @code = RecItemCode, RecUsername from Receipt where RecTransaction = @id

It is mixing variable assignment and data retrieval. This highlights a couple of points. If you need the data that is driving @code in addition to other parts of the data, forget the output parameter and just select the data.

Select RecItemCode, RecUsername from Receipt where RecTransaction = @id

If you just need the code, use the first SQL statement I showed you. On the offhand chance you actually need the output and the data, use two different statements

Select @code = RecItemCode from Receipt where RecTransaction = @id
Select RecItemCode, RecUsername from Receipt where RecTransaction = @id

This should assign your value to the output parameter as well as return two columns of data in a row. However, this strikes me as terribly redundant.

If you write your SP as I have shown at the very top, simply invoke cmd.ExecuteNonQuery(); and then read the output parameter value.


Another issue with your SP and code. In your SP, you have declared @code as varchar. In your code, you specify the parameter type as Int. Either change your SP or your code to make the types consistent.


Also note: If all you are doing is returning a single value, there's another way to do it that does not involve output parameters at all. You could write

 Select RecItemCode from Receipt where RecTransaction = @id

And then use object obj = cmd.ExecuteScalar(); to get the result, no need for an output parameter in the SP or in your code.

Twitter-Bootstrap-2 logo image on top of navbar

Overwrite the brand class, either in the bootstrap.css or a new CSS file, as below -

.brand
{
  background: url(images/logo.png) no-repeat left center;
  height: 20px;
  width: 100px;
}

and your html should look like -

<div class="container-fluid">
  <a class="brand" href="index.html"></a>
</div>

firestore: PERMISSION_DENIED: Missing or insufficient permissions

Check if the service account is added in IAM & Admin https://console.cloud.google.com/iam-admin/iam with an appropriate role such as Editor

how to properly display an iFrame in mobile safari

Yeah, you can't constrain the iframe itself with height and width. You should put a div around it. If you control the content in the iframe, you can put some JS within the iframe content that will tell the parent to scroll the div when the touch event is received.

like this:

The JS:

setTimeout(function () {
var startY = 0;
var startX = 0;
var b = document.body;
b.addEventListener('touchstart', function (event) {
    parent.window.scrollTo(0, 1);
    startY = event.targetTouches[0].pageY;
    startX = event.targetTouches[0].pageX;
});
b.addEventListener('touchmove', function (event) {
    event.preventDefault();
    var posy = event.targetTouches[0].pageY;
    var h = parent.document.getElementById("scroller");
    var sty = h.scrollTop;

    var posx = event.targetTouches[0].pageX;
    var stx = h.scrollLeft;
    h.scrollTop = sty - (posy - startY);
    h.scrollLeft = stx - (posx - startX);
    startY = posy;
    startX = posx;
});
}, 1000);

The HTML:

<div id="scroller" style="height: 400px; width: 100%; overflow: auto;">
<iframe height="100%" id="iframe" scrolling="no" width="100%" id="iframe" src="url" />
</div>

If you don't control the iframe content, you can use an overlay over the iframe in a similar manner, but then you can't interact with the iframe contents other than to scroll it - so you can't, for example, click links in the iframe.

It used to be that you could use two fingers to scroll within an iframe, but that doesn't work anymore.

Update: iOS 6 broke this solution for us. I've been attempting to get a new fix for it, but nothing has worked yet. In addition, it is no longer possible to debug javascript on the device since they introduced Remote Web Inspector, which requires a Mac to use.

JavaScript replace \n with <br />

Handles either type of line break

str.replace(new RegExp('\r?\n','g'), '<br />');

Fullscreen Activity in Android?

show Full Immersive:

private void askForFullScreen()
    {
        getActivity().getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION // hide nav bar
                        | View.SYSTEM_UI_FLAG_FULLSCREEN // hide status bar
                        | View.SYSTEM_UI_FLAG_IMMERSIVE);
    }

move out of full immersive mode:

 private void moveOutOfFullScreen() {
        getActivity().getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
    }

Is there a Java equivalent or methodology for the typedef keyword in C++?

There is no typedef in java as of 1.6, what you can do is make a wrapper class for what you want since you can't subclass final classes (Integer, Double, etc)

How to use Visual Studio Code as Default Editor for Git

Just want to add these back slashes to previous answers, I am on Windows 10 CMD, and it doesn't work without back slashes before the spaces.

git config --global core.editor "C:\\Users\\your_user_name\\AppData\\Local\\Programs\\Microsoft\ VS\ Code\\Code.exe"

null terminating a string

Be very careful: NULL is a macro used mainly for pointers. The standard way of terminating a string is:

char *buffer;
...
buffer[end_position] = '\0';

This (below) works also but it is not a big difference between assigning an integer value to a int/short/long array and assigning a character value. This is why the first version is preferred and personally I like it better.

buffer[end_position] = 0; 

string in namespace std does not name a type

Nouns.h doesn't include <string>, but it needs to. You need to add

#include <string>

at the top of that file, otherwise the compiler doesn't know what std::string is when it is encountered for the first time.

req.body empty on posts

Thank you all for your great answers! Spent quite some time searching for a solution, and on my side I was making an elementary mistake: I was calling bodyParser.json() from within the function :

_x000D_
_x000D_
app.use(['/password'], async (req, res, next) => {_x000D_
  bodyParser.json()_x000D_
  /.../_x000D_
  next()_x000D_
})
_x000D_
_x000D_
_x000D_

I just needed to do app.use(['/password'], bodyParser.json()) and it worked...

Can a Windows batch file determine its own file name?

Yes.

Use the special %0 variable to get the path to the current file.

Write %~n0 to get just the filename without the extension.

Write %~n0%~x0 to get the filename and extension.

Also possible to write %~nx0 to get the filename and extension.

Django model "doesn't declare an explicit app_label"

I get the same error and I don´t know how to figure out this problem. It took me many hours to notice that I have a init.py at the same direcory as the manage.py from django.

Before:

|-- myproject
  |-- __init__.py
  |-- manage.py
  |-- myproject
    |-- ...
  |-- app1
    |-- models.py
  |-- app2
    |-- models.py

After:

|-- myproject
  |-- manage.py
  |-- myproject
    |-- ...
  |-- app1
    |-- models.py
  |-- app2
    |-- models.py

It is quite confused that you get this "doesn't declare an explicit app_label" error. But deleting this init file solved my problem.

How to get a unique device ID in Swift?

Swift 2.2

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

    let userDefaults = NSUserDefaults.standardUserDefaults()

    if userDefaults.objectForKey("ApplicationIdentifier") == nil {
        let UUID = NSUUID().UUIDString
        userDefaults.setObject(UUID, forKey: "ApplicationIdentifier")
        userDefaults.synchronize()
    }
    return true
}

//Retrieve
print(NSUserDefaults.standardUserDefaults().valueForKey("ApplicationIdentifier")!)

Reset textbox value in javascript

I know this is an old post, but this may help clarify:

$('#searchField')
    .val('')// [property value] e.g. what is visible / will be submitted
    .attr('value', '');// [attribute value] e.g. <input value="preset" ...

Changing [attribute value] has no effect if there is a [property value]. (user || js altered input)

Sorting a Dictionary in place with respect to keys

Take a look at SortedDictionary, there's even a constructor overload so you can pass in your own IComparable for the comparisons.

Android Studio Emulator and "Process finished with exit code 0"

This can be solved by the following step:

Please ensure "Windows Hypervisor Platform" is installed. If it's not installed, install it, restart your computer and you will be good to go.

enter image description here

What is the best method to merge two PHP objects?

Here is a function that will flatten an object or array. Use this only if you are sure your keys are unique. If you have keys with the same name they will be overwritten. You will need to place this in a class and replace "Functions" with the name of your class. Enjoy...

function flatten($array, $preserve_keys=1, &$out = array(), $isobject=0) {
        # Flatten a multidimensional array to one dimension, optionally preserving keys.
        #
        # $array - the array to flatten
        # $preserve_keys - 0 (default) to not preserve keys, 1 to preserve string keys only, 2 to preserve all keys
        # $out - internal use argument for recursion
        # $isobject - is internally set in order to remember if we're using an object or array
        if(is_array($array) || $isobject==1)
        foreach($array as $key => $child)
            if(is_array($child))
                $out = Functions::flatten($child, $preserve_keys, $out, 1); // replace "Functions" with the name of your class
            elseif($preserve_keys + is_string($key) > 1)
                $out[$key] = $child;
            else
                $out[] = $child;

        if(is_object($array) || $isobject==2)
        if(!is_object($out)){$out = new stdClass();}
        foreach($array as $key => $child)
            if(is_object($child))
                $out = Functions::flatten($child, $preserve_keys, $out, 2); // replace "Functions" with the name of your class
            elseif($preserve_keys + is_string($key) > 1)
                $out->$key = $child;
            else
                $out = $child;

        return $out;
}

Unknown URL content://downloads/my_downloads

I have encountered the exception java.lang.IllegalArgumentException: Unknown URI: content://downloads/public_downloads/7505 in getting the doucument from the downloads. This solution worked for me.

else if (isDownloadsDocument(uri)) {
            String fileName = getFilePath(context, uri);
            if (fileName != null) {
                return Environment.getExternalStorageDirectory().toString() + "/Download/" + fileName;
            }

            String id = DocumentsContract.getDocumentId(uri);
            if (id.startsWith("raw:")) {
                id = id.replaceFirst("raw:", "");
                File file = new File(id);
                if (file.exists())
                    return id;
            }

            final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
            return getDataColumn(context, contentUri, null, null);
        }

This the method used to get the filepath

   public static String getFilePath(Context context, Uri uri) {

    Cursor cursor = null;
    final String[] projection = {
            MediaStore.MediaColumns.DISPLAY_NAME
    };

    try {
        cursor = context.getContentResolver().query(uri, projection, null, null,
                null);
        if (cursor != null && cursor.moveToFirst()) {
            final int index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DISPLAY_NAME);
            return cursor.getString(index);
        }
    } finally {
        if (cursor != null)
            cursor.close();
    }
    return null;
}

How to iterate over arguments in a Bash script

You can also access them as an array elements, for example if you don't want to iterate through all of them

argc=$#
argv=("$@")

for (( j=0; j<argc; j++ )); do
    echo "${argv[j]}"
done

Deleting a file in VBA

In VB its normally Dir to find the directory of the file. If it's not blank then it exists and then use Kill to get rid of the file.

test = Dir(Filename)
If Not test = "" Then
    Kill (Filename)
End If

How to instantiate a File object in JavaScript?

The idea ...To create a File object (api) in javaScript for images already present in the DOM :

<img src="../img/Products/fijRKjhudDjiokDhg1524164151.jpg">

var file = new File(['fijRKjhudDjiokDhg1524164151'],
                     '../img/Products/fijRKjhudDjiokDhg1524164151.jpg', 
                     {type:'image/jpg'});

// created object file
console.log(file);

Don't do that ! ... (but I did it anyway)

-> the console give a result similar as an Object File :

File(0) {name: "fijRKjokDhgfsKtG1527053050.jpg", lastModified: 1527053530715, lastModifiedDate: Wed May 23 2018 07:32:10 GMT+0200 (Paris, Madrid (heure d’été)), webkitRelativePath: "", size: 0, …}
lastModified:1527053530715
lastModifiedDate:Wed May 23 2018 07:32:10 GMT+0200 (Paris, Madrid (heure d’été)) {}
name:"fijRKjokDhgfsKtG1527053050.jpg"
size:0
type:"image/jpg"
webkitRelativePath:""__proto__:File

But the size of the object is wrong ...

Why i need to do that ?

For example to retransmit an image form already uploaded, during a product update, along with additional images added during the update

z-index issue with twitter bootstrap dropdown menu

Solved this issue by removing transform: translateY(50%); property.

generate model using user:references vs user_id:integer

how does rails know that user_id is a foreign key referencing user?

Rails itself does not know that user_id is a foreign key referencing user. In the first command rails generate model Micropost user_id:integer it only adds a column user_id however rails does not know the use of the col. You need to manually put the line in the Micropost model

class Micropost < ActiveRecord::Base
  belongs_to :user
end

class User < ActiveRecord::Base
  has_many :microposts
end

the keywords belongs_to and has_many determine the relationship between these models and declare user_id as a foreign key to User model.

The later command rails generate model Micropost user:references adds the line belongs_to :user in the Micropost model and hereby declares as a foreign key.

FYI
Declaring the foreign keys using the former method only lets the Rails know about the relationship the models/tables have. The database is unknown about the relationship. Therefore when you generate the EER Diagrams using software like MySql Workbench you find that there is no relationship threads drawn between the models. Like in the following pic enter image description here

However, if you use the later method you find that you migration file looks like:

def change
    create_table :microposts do |t|
      t.references :user, index: true

      t.timestamps null: false
    end
    add_foreign_key :microposts, :users

Now the foreign key is set at the database level. and you can generate proper EER diagrams. enter image description here

How to present a modal atop the current view in Swift

The only problem I can see in your code is that you are using CurrentContext instead of OverCurrentContext.

So, replace this:

self.modalPresentationStyle = UIModalPresentationStyle.CurrentContext
self.navigationController.modalPresentationStyle = UIModalPresentationStyle.CurrentContext

for this:

self.modalPresentationStyle = UIModalPresentationStyle.OverCurrentContext
self.navigationController.modalPresentationStyle = UIModalPresentationStyle.OverCurrentContext

Rebasing remote branches in Git

You can disable the check (if you're really sure you know what you're doing) by using the --force option to git push.

Set value to an entire column of a pandas dataframe

Seems to me that:

df1 = df[df['col1']==some_value] WILL NOT create a new DataFrame, basically, changes in df1 will be reflected in the parent df. This leads to the warning. Whereas, df1 = df[df['col1]]==some_value].copy() WILL create a new DataFrame, and changes in df1 will not be reflected in df. the copy() method is recommended if you don't want to make changes to your original df.

How do I specify different Layouts in the ASP.NET MVC 3 razor ViewStart file?

This method is the simplest way for beginners to control Layouts rendering in your ASP.NET MVC application. We can identify the controller and render the Layouts as par controller, to do this we can write our code in _ViewStart file in the root directory of the Views folder. Following is an example shows how it can be done.

@{
    var controller = HttpContext.Current.Request.RequestContext.RouteData.Values["Controller"].ToString();
    string cLayout = "";

    if (controller == "Webmaster")
        cLayout = "~/Views/Shared/_WebmasterLayout.cshtml";
    else
        cLayout = "~/Views/Shared/_Layout.cshtml";

    Layout = cLayout;
}

Read Complete Article here "How to Render different Layout in ASP.NET MVC"

How do I fix the "You don't have write permissions into the /usr/bin directory" error when installing Rails?

use -n parameter to install like for cocoapods:

sudo gem install cocoapods -n /usr/local/bin

Converting date between DD/MM/YYYY and YYYY-MM-DD?

In case you need to convert an entire column of data (from pandas DataFrame), then first convert it (pandas Series) to the datetime format using to_datetime and finally use .dt.strftime:

def conv_dates_series(df, col, old_date_format, new_date_format):

    df[col] = pd.to_datetime(df[col], format=old_date_format).dt.strftime(new_date_format)

    return(df)

Sample usage:

import pandas as pd

test_df = pd.DataFrame({"Dates": ["1900-01-01", "1999-12-31"]})

old_date_format='%d/%m/%Y'
new_date_format='%Y-%m-%d'

conv_dates_series(test_df, "Dates", old_date_format, new_date_format)

How to load property file from classpath?

final Properties properties = new Properties();
try (final InputStream stream =
           this.getClass().getResourceAsStream("foo.properties")) {
    properties.load(stream);
    /* or properties.loadFromXML(...) */
}

Drop primary key using script in SQL Server database

The answer I got is that variables and subqueries will not work and we have to user dynamic SQL script. The following works:

DECLARE @SQL VARCHAR(4000)
SET @SQL = 'ALTER TABLE dbo.Student DROP CONSTRAINT |ConstraintName| '

SET @SQL = REPLACE(@SQL, '|ConstraintName|', ( SELECT   name
                                               FROM     sysobjects
                                               WHERE    xtype = 'PK'
                                                        AND parent_obj =        OBJECT_ID('Student')))

EXEC (@SQL)

New to unit testing, how to write great tests?

Don't write tests to get full coverage of your code. Write tests that guarantee your requirements. You may discover codepaths that are unnecessary. Conversely, if they are necessary, they are there to fulfill some kind of requirement; find it what it is and test the requirement (not the path).

Keep your tests small: one test per requirement.

Later, when you need to make a change (or write new code), try writing one test first. Just one. Then you'll have taken the first step in test-driven development.

Immutable array in Java

The of(E... elements) method in Java9 can be used to create immutable list using just a line:

List<Integer> items = List.of(1,2,3,4,5);

The above method returns an immutable list containing an arbitrary number of elements. And adding any integer to this list would result in java.lang.UnsupportedOperationExceptionexception. This method also accepts a single array as an argument.

String[] array = ... ;
List<String[]> list = List.<String[]>of(array);

HTTP Range header

As Wrikken suggested, it's a valid request. It's also quite common when the client is requesting media or resuming a download.

A client will often test to see if the server handles ranged requests other than just looking for an Accept-Ranges response. Chrome always sends a Range: bytes=0- with its first GET request for a video, so it's something you can't dismiss.

Whenever a client includes Range: in its request, even if it's malformed, it's expecting a partial content (206) response. When you seek forward during HTML5 video playback, the browser only requests the starting point. For example:

Range: bytes=3744-

So, in order for the client to play video properly, your server must be able to handle these incomplete range requests.

You can handle the type of 'range' you specified in your question in two ways:

First, You could reply with the requested starting point given in the response, then the total length of the file minus one (the requested byte range is zero-indexed). For example:

Request:

GET /BigBuckBunny_320x180.mp4 
Range: bytes=100-

Response:

206 Partial Content
Content-Type: video/mp4
Content-Length: 64656927
Accept-Ranges: bytes
Content-Range: bytes 100-64656926/64656927

Second, you could reply with the starting point given in the request and an open-ended file length (size). This is for webcasts or other media where the total length is unknown. For example:

Request:

GET /BigBuckBunny_320x180.mp4
Range: bytes=100-

Response:

206 Partial Content
Content-Type: video/mp4
Content-Length: 64656927
Accept-Ranges: bytes
Content-Range: bytes 100-64656926/*

Tips:

You must always respond with the content length included with the range. If the range is complete, with start to end, then the content length is simply the difference:

Request: Range: bytes=500-1000

Response: Content-Range: bytes 500-1000/123456

Remember that the range is zero-indexed, so Range: bytes=0-999 is actually requesting 1000 bytes, not 999, so respond with something like:

Content-Length: 1000
Content-Range: bytes 0-999/123456

Or:

Content-Length: 1000
Content-Range: bytes 0-999/*

But, avoid the latter method if possible because some media players try to figure out the duration from the file size. If your request is for media content, which is my hunch, then you should include its duration in the response. This is done with the following format:

X-Content-Duration: 63.23 

This must be a floating point. Unlike Content-Length, this value doesn't have to be accurate. It's used to help the player seek around the video. If you are streaming a webcast and only have a general idea of how long it will be, it's better to include your estimated duration rather than ignore it altogether. So, for a two-hour webcast, you could include something like:

X-Content-Duration: 7200.00 

With some media types, such as webm, you must also include the content-type, such as:

Content-Type: video/webm 

All of these are necessary for the media to play properly, especially in HTML5. If you don't give a duration, the player may try to figure out the duration (to allow for seeking) from its file size, but this won't be accurate. This is fine, and necessary for webcasts or live streaming, but not ideal for playback of video files. You can extract the duration using software like FFMPEG and save it in a database or even the filename.

X-Content-Duration is being phased out in favor of Content-Duration, so I'd include that too. A basic, response to a "0-" request would include at least the following:

HTTP/1.1 206 Partial Content
Date: Sun, 08 May 2013 06:37:54 GMT
Server: Apache/2.0.52 (Red Hat)
Accept-Ranges: bytes
Content-Length: 3980
Content-Range: bytes 0-3979/3980
Content-Type: video/webm
X-Content-Duration: 2054.53
Content-Duration: 2054.53

One more point: Chrome always starts its first video request with the following:

Range: bytes=0-

Some servers will send a regular 200 response as a reply, which it accepts (but with limited playback options), but try to send a 206 instead to show than your server handles ranges. RFC 2616 says it's acceptable to ignore range headers.

Is an entity body allowed for an HTTP DELETE request?

I don't think a good answer to this has been posted, although there's been lots of great comments on existing answers. I'll lift the gist of those comments into a new answer:

This paragraph from RFC7231 has been quoted a few times, which does sum it up.

A payload within a DELETE request message has no defined semantics; sending a payload body on a DELETE request might cause some existing implementations to reject the request.

What I missed from the other answers was the implication. Yes it is allowed to include a body on DELETE requests, but it's semantically meaningless. What this really means is that issuing a DELETE request with a request body is semantically equivalent to not including a request body.

Including a request body should not have any effect on the request, so there is never a point in including it.

tl;dr: Techically a DELETE request with a request body is allowed, but it's never useful to do so.

How do I install jmeter on a Mac?

jmeter is now just installed with

brew install jmeter

This version includes the plugin manager that you can use to download the additional plugins.

OUTDATED:

If you want to include the plugins (JMeterPlugins Standard, Extras, ExtrasLibs, WebDriver and Hadoop) use:

brew install jmeter --with-plugins

Installed Ruby 1.9.3 with RVM but command line doesn't show ruby -v

I ran into a similar issue today - my ruby version didn't match my rvm installs.

> ruby -v
ruby 2.0.0p481

> rvm list
rvm rubies
   ruby-2.1.2 [ x86_64 ]
=* ruby-2.2.1 [ x86_64 ]
   ruby-2.2.3 [ x86_64 ]

Also, rvm current failed.

> rvm current
Warning! PATH is not properly set up, '/Users/randallreed/.rvm/gems/ruby-2.2.1/bin' is not at first place...

The error message recommended this useful command, which resolved the issue for me:

> rvm get stable --auto-dotfiles

SQL Server: how to create a stored procedure

Try this:

 create procedure dept_count(@dept_name varchar(20),@d_count int)
       begin
         set @d_count=(select count(*)
                       from instructor
                        where instructor.dept_name=dept_count.dept_name)
         Select @d_count as count
       end

Or

create procedure dept_count(@dept_name varchar(20))
           begin
            select count(*)
                           from instructor
                            where instructor.dept_name=dept_count.dept_name
           end

PHP cURL, extract an XML response

simple load xml file ..

$xml = @simplexml_load_string($retValuet);

$status = (string)$xml->Status; 
$operator_trans_id = (string)$xml->OPID;
$trns_id = (string)$xml->TID;

?>

How do I insert a JPEG image into a python Tkinter window?

from tkinter import *
from PIL import ImageTk, Image

window = Tk()
window.geometry("1000x300")

path = "1.jpg"

image = PhotoImage(Image.open(path))

panel = Label(window, image = image)

panel.pack()

window.mainloop()

Simple and fast method to compare images for similarity

Does the screenshot contain only the icon? If so, the L2 distance of the two images might suffice. If the L2 distance doesn't work, the next step is to try something simple and well established, like: Lucas-Kanade. Which I'm sure is available in OpenCV.

Pandas percentage of total with groupby

Simple way I have used is a merge after the 2 groupby's then doing simple division.

import numpy as np
import pandas as pd
np.random.seed(0)
df = pd.DataFrame({'state': ['CA', 'WA', 'CO', 'AZ'] * 3,
               'office_id': list(range(1, 7)) * 2,
               'sales': [np.random.randint(100000, 999999) for _ in range(12)]})

state_office = df.groupby(['state', 'office_id'])['sales'].sum().reset_index()
state = df.groupby(['state'])['sales'].sum().reset_index()
state_office = state_office.merge(state, left_on='state', right_on ='state', how = 'left')
state_office['sales_ratio'] = 100*(state_office['sales_x']/state_office['sales_y'])

   state  office_id  sales_x  sales_y  sales_ratio
0     AZ          2   222579  1310725    16.981365
1     AZ          4   252315  1310725    19.250033
2     AZ          6   835831  1310725    63.768601
3     CA          1   405711  2098663    19.331879
4     CA          3   710581  2098663    33.858747
5     CA          5   982371  2098663    46.809373
6     CO          1   404137  1096653    36.851857
7     CO          3   217952  1096653    19.874290
8     CO          5   474564  1096653    43.273852
9     WA          2   535829  1543854    34.707233
10    WA          4   548242  1543854    35.511259
11    WA          6   459783  1543854    29.781508

Java - get pixel array from image

Something like this?

int[][] pixels = new int[w][h];

for( int i = 0; i < w; i++ )
    for( int j = 0; j < h; j++ )
        pixels[i][j] = img.getRGB( i, j );

Find the paths between two given nodes?

given the adjacency matrix:

{0, 1, 3, 4, 0, 0}

{0, 0, 2, 1, 2, 0}

{0, 1, 0, 3, 0, 0}

{0, 1, 1, 0, 0, 1}

{0, 0, 0, 0, 0, 6}

{0, 1, 0, 1, 0, 0}

the following Wolfram Mathematica code solve the problem to find all the simple paths between two nodes of a graph. I used simple recursion, and two global var to keep track of cycles and to store the desired output. the code hasn't been optimized just for the sake of code clarity. the "print" should be helpful to clarify how it works.

cycleQ[l_]:=If[Length[DeleteDuplicates[l]] == Length[l], False, True];
getNode[matrix_, node_]:=Complement[Range[Length[matrix]],Flatten[Position[matrix[[node]], 0]]];

builtTree[node_, matrix_]:=Block[{nodes, posAndNodes, root, pos},
    If[{node} != {} && node != endNode ,
        root = node;
        nodes = getNode[matrix, node];
        (*Print["root:",root,"---nodes:",nodes];*)

        AppendTo[lcycle, Flatten[{root, nodes}]];
        If[cycleQ[lcycle] == True,
            lcycle = Most[lcycle]; appendToTree[root, nodes];,
            Print["paths: ", tree, "\n", "root:", root, "---nodes:",nodes];
            appendToTree[root, nodes];

        ];
    ];

appendToTree[root_, nodes_] := Block[{pos, toAdd},
    pos = Flatten[Position[tree[[All, -1]], root]];
    For[i = 1, i <= Length[pos], i++,
        toAdd = Flatten[Thread[{tree[[pos[[i]]]], {#}}]] & /@ nodes;
        (* check cycles!*)            
        If[cycleQ[#] != True, AppendTo[tree, #]] & /@ toAdd;
    ];
    tree = Delete[tree, {#} & /@ pos];
    builtTree[#, matrix] & /@ Union[tree[[All, -1]]];
    ];
];

to call the code: initNode = 1; endNode = 6; lcycle = {}; tree = {{initNode}}; builtTree[initNode, matrix];

paths: {{1}} root:1---nodes:{2,3,4}

paths: {{1,2},{1,3},{1,4}} root:2---nodes:{3,4,5}

paths: {{1,3},{1,4},{1,2,3},{1,2,4},{1,2,5}} root:3---nodes:{2,4}

paths: {{1,4},{1,2,4},{1,2,5},{1,3,4},{1,2,3,4},{1,3,2,4},{1,3,2,5}} root:4---nodes:{2,3,6}

paths: {{1,2,5},{1,3,2,5},{1,4,6},{1,2,4,6},{1,3,4,6},{1,2,3,4,6},{1,3,2,4,6},{1,4,2,5},{1,3,4,2,5},{1,4,3,2,5}} root:5---nodes:{6}

RESULTS:{{1, 4, 6}, {1, 2, 4, 6}, {1, 2, 5, 6}, {1, 3, 4, 6}, {1, 2, 3, 4, 6}, {1, 3, 2, 4, 6}, {1, 3, 2, 5, 6}, {1, 4, 2, 5, 6}, {1, 3, 4, 2, 5, 6}, {1, 4, 3, 2, 5, 6}}

...Unfortunately I cannot upload images to show the results in a better way :(

http://textanddatamining.blogspot.com

How to set Android camera orientation properly?

check out this solution

 public static void setCameraDisplayOrientation(Activity activity,
                                                   int cameraId, android.hardware.Camera camera) {
        android.hardware.Camera.CameraInfo info =
                new android.hardware.Camera.CameraInfo();
        android.hardware.Camera.getCameraInfo(cameraId, info);
        int rotation = activity.getWindowManager().getDefaultDisplay()
                .getRotation();
        int degrees = 0;
        switch (rotation) {
            case Surface.ROTATION_0: degrees = 0; break;
            case Surface.ROTATION_90: degrees = 90; break;
            case Surface.ROTATION_180: degrees = 180; break;
            case Surface.ROTATION_270: degrees = 270; break;
        }

        int result;
        if (info.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) {
            result = (info.orientation + degrees) % 360;
            result = (360 - result) % 360;  // compensate the mirror
        } else {  // back-facing
            result = (info.orientation - degrees + 360) % 360;
        }
        camera.setDisplayOrientation(result);
    }

In C#, what's the difference between \n and \r\n?

Basically comes down to Windows standard: \r\n and Unix based systems using: \n

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

Linux command: How to 'find' only text files?

I have two issues with histumness' answer:

  • It only list text files. It does not actually search them as requested. To actually search, use

    find . -type f -exec grep -Iq . {} \; -and -print0 | xargs -0 grep "needle text"
    
  • It spawns a grep process for every file, which is very slow. A better solution is then

    find . -type f -print0 | xargs -0 grep -IZl . | xargs -0 grep "needle text"
    

    or simply

    find . -type f -print0 | xargs -0 grep -I "needle text"
    

    This only takes 0.2s compared to 4s for solution above (2.5GB data / 7700 files), i.e. 20x faster.

Also, nobody cited ag, the Silver Searcher or ack-grep¸as alternatives. If one of these are available, they are much better alternatives:

ag -t "needle text"    # Much faster than ack
ack -t "needle text"   # or ack-grep

As a last note, beware of false positives (binary files taken as text files). I already had false positive using either grep/ag/ack, so better list the matched files first before editing the files.

Get an element by index in jQuery

You could skip the jquery and just use CSS style tagging:

 <ul>
 <li>India</li>
 <li>Indonesia</li>
 <li style="background-color:#343434;">China</li>
 <li>United States</li>
 <li>United Kingdom</li>
 </ul>

ASP.NET MVC controller actions that return JSON or partial html

    public ActionResult GetExcelColumn()
    {            
            List<string> lstAppendColumn = new List<string>();
            lstAppendColumn.Add("First");
            lstAppendColumn.Add("Second");
            lstAppendColumn.Add("Third");
  return Json(new { lstAppendColumn = lstAppendColumn,  Status = "Success" }, JsonRequestBehavior.AllowGet);
            }
        }

Bootstrap 3 scrollable div for table

Well one way to do it is set the height of your body to the height that you want your page to be. In this example I did 600px.

Then set your wrapper height to a percentage of the body here I did 70% This will adjust your table so that it does not fill up the whole screen but in stead just takes up a percentage of the specified page height.

body {
   padding-top: 70px;
   border:1px solid black;
   height:600px;
}

.mygrid-wrapper-div {
   border: solid red 5px;
   overflow: scroll;
   height: 70%;
}

http://jsfiddle.net/4NB2N/7/

Update How about a jQuery approach.

$(function() {  
   var window_height = $(window).height(),
   content_height = window_height - 200;
   $('.mygrid-wrapper-div').height(content_height);
});

$( window ).resize(function() {
   var window_height = $(window).height(),
   content_height = window_height - 200;
   $('.mygrid-wrapper-div').height(content_height);
});

http://jsfiddle.net/4NB2N/11/

JSON serialization/deserialization in ASP.Net Core

You can use Newtonsoft.Json, it's a dependency of Microsoft.AspNet.Mvc.ModelBinding which is a dependency of Microsoft.AspNet.Mvc. So, you don't need to add a dependency in your project.json.

#using Newtonsoft.Json
....
JsonConvert.DeserializeObject(json);

Note, using a WebAPI controller you don't need to deal with JSON.

UPDATE ASP.Net Core 3.0

Json.NET has been removed from the ASP.NET Core 3.0 shared framework.

You can use the new JSON serializer layers on top of the high-performance Utf8JsonReader and Utf8JsonWriter. It deserializes objects from JSON and serializes objects to JSON. Memory allocations are kept minimal and includes support for reading and writing JSON with Stream asynchronously.

To get started, use the JsonSerializer class in the System.Text.Json.Serialization namespace. See the documentation for information and samples.

To use Json.NET in an ASP.NET Core 3.0 project:

    services.AddMvc()
        .AddNewtonsoftJson();

Read Json.NET support in Migrate from ASP.NET Core 2.2 to 3.0 Preview 2 for more information.

Zooming MKMapView to fit annotation pins?

For iOS 7 and above (Referring MKMapView.h) :

// Position the map such that the provided array of annotations are all visible to the fullest extent possible.          

- (void)showAnnotations:(NSArray *)annotations animated:(BOOL)animated NS_AVAILABLE(10_9, 7_0);

remark from – Abhishek Bedi

You just call:

 [yourMapView showAnnotations:@[yourAnnotation] animated:YES];

Convert pandas timezone-aware DateTimeIndex to naive timestamp, but in certain timezone

Setting the tz attribute of the index explicitly seems to work:

ts_utc = ts.tz_convert("UTC")
ts_utc.index.tz = None

How to modify existing XML file with XmlDocument and XmlNode in C#

You need to do something like this:

// instantiate XmlDocument and load XML from file
XmlDocument doc = new XmlDocument();
doc.Load(@"D:\test.xml");

// get a list of nodes - in this case, I'm selecting all <AID> nodes under
// the <GroupAIDs> node - change to suit your needs
XmlNodeList aNodes = doc.SelectNodes("/Equipment/DataCollections/GroupAIDs/AID");

// loop through all AID nodes
foreach (XmlNode aNode in aNodes)
{
   // grab the "id" attribute
   XmlAttribute idAttribute = aNode.Attributes["id"];

   // check if that attribute even exists...
   if (idAttribute != null)
   {
      // if yes - read its current value
      string currentValue = idAttribute.Value;

      // here, you can now decide what to do - for demo purposes,
      // I just set the ID value to a fixed value if it was empty before
      if (string.IsNullOrEmpty(currentValue))
      {
         idAttribute.Value = "515";
      }
   }
}

// save the XmlDocument back to disk
doc.Save(@"D:\test2.xml");

How to count items in JSON data

import json

json_data = json.dumps({
  "result":[
    {
      "run":[
        {
          "action":"stop"
        },
        {
          "action":"start"
        },
        {
          "action":"start"
        }
      ],
      "find": "true"
    }
  ]
})

item_dict = json.loads(json_data)
print len(item_dict['result'][0]['run'])

Convert it in dict.

Print all but the first three columns

Pretty much all the answers currently add either leading spaces, trailing spaces or some other separator issue. To select from the fourth field where the separator is whitespace and the output separator is a single space using awk would be:

awk '{for(i=4;i<=NF;i++)printf "%s",$i (i==NF?ORS:OFS)}' file

To parametrize the starting field you could do:

awk '{for(i=n;i<=NF;i++)printf "%s",$i (i==NF?ORS:OFS)}' n=4 file

And also the ending field:

awk '{for(i=n;i<=m=(m>NF?NF:m);i++)printf "%s",$i (i==m?ORS:OFS)}' n=4 m=10 file

In Angular, how to add Validator to FormControl after control is created?

In addition to Eduard Void answer here's the addValidators method:

declare module '@angular/forms' {
  interface FormControl {
    addValidators(validators: ValidatorFn[]): void;
  }
}

FormControl.prototype.addValidators = function(this: FormControl, validators: ValidatorFn[]) {
  if (!validators || !validators.length) {
    return;
  }

  this.clearValidators();
  this.setValidators( this.validator ? [ this.validator, ...validators ] : validators );
};

Using it you can set validators dynamically:

some_form_control.addValidators([ first_validator, second_validator ]);
some_form_control.addValidators([ third_validator ]);

A simple explanation of Naive Bayes Classification

Ram Narasimhan explained the concept very nicely here below is an alternative explanation through the code example of Naive Bayes in action
It uses an example problem from this book on page 351
This is the data set that we will be using
enter image description here
In the above dataset if we give the hypothesis = {"Age":'<=30', "Income":"medium", "Student":'yes' , "Creadit_Rating":'fair'} then what is the probability that he will buy or will not buy a computer.
The code below exactly answers that question.
Just create a file called named new_dataset.csv and paste the following content.

Age,Income,Student,Creadit_Rating,Buys_Computer
<=30,high,no,fair,no
<=30,high,no,excellent,no
31-40,high,no,fair,yes
>40,medium,no,fair,yes
>40,low,yes,fair,yes
>40,low,yes,excellent,no
31-40,low,yes,excellent,yes
<=30,medium,no,fair,no
<=30,low,yes,fair,yes
>40,medium,yes,fair,yes
<=30,medium,yes,excellent,yes
31-40,medium,no,excellent,yes
31-40,high,yes,fair,yes
>40,medium,no,excellent,no

Here is the code the comments explains everything we are doing here! [python]

import pandas as pd 
import pprint 

class Classifier():
    data = None
    class_attr = None
    priori = {}
    cp = {}
    hypothesis = None


    def __init__(self,filename=None, class_attr=None ):
        self.data = pd.read_csv(filename, sep=',', header =(0))
        self.class_attr = class_attr

    '''
        probability(class) =    How many  times it appears in cloumn
                             __________________________________________
                                  count of all class attribute
    '''
    def calculate_priori(self):
        class_values = list(set(self.data[self.class_attr]))
        class_data =  list(self.data[self.class_attr])
        for i in class_values:
            self.priori[i]  = class_data.count(i)/float(len(class_data))
        print "Priori Values: ", self.priori

    '''
        Here we calculate the individual probabilites 
        P(outcome|evidence) =   P(Likelihood of Evidence) x Prior prob of outcome
                               ___________________________________________
                                                    P(Evidence)
    '''
    def get_cp(self, attr, attr_type, class_value):
        data_attr = list(self.data[attr])
        class_data = list(self.data[self.class_attr])
        total =1
        for i in range(0, len(data_attr)):
            if class_data[i] == class_value and data_attr[i] == attr_type:
                total+=1
        return total/float(class_data.count(class_value))

    '''
        Here we calculate Likelihood of Evidence and multiple all individual probabilities with priori
        (Outcome|Multiple Evidence) = P(Evidence1|Outcome) x P(Evidence2|outcome) x ... x P(EvidenceN|outcome) x P(Outcome)
        scaled by P(Multiple Evidence)
    '''
    def calculate_conditional_probabilities(self, hypothesis):
        for i in self.priori:
            self.cp[i] = {}
            for j in hypothesis:
                self.cp[i].update({ hypothesis[j]: self.get_cp(j, hypothesis[j], i)})
        print "\nCalculated Conditional Probabilities: \n"
        pprint.pprint(self.cp)

    def classify(self):
        print "Result: "
        for i in self.cp:
            print i, " ==> ", reduce(lambda x, y: x*y, self.cp[i].values())*self.priori[i]

if __name__ == "__main__":
    c = Classifier(filename="new_dataset.csv", class_attr="Buys_Computer" )
    c.calculate_priori()
    c.hypothesis = {"Age":'<=30', "Income":"medium", "Student":'yes' , "Creadit_Rating":'fair'}

    c.calculate_conditional_probabilities(c.hypothesis)
    c.classify()

output:

Priori Values:  {'yes': 0.6428571428571429, 'no': 0.35714285714285715}

Calculated Conditional Probabilities: 

{
 'no': {
        '<=30': 0.8,
        'fair': 0.6, 
        'medium': 0.6, 
        'yes': 0.4
        },
'yes': {
        '<=30': 0.3333333333333333,
        'fair': 0.7777777777777778,
        'medium': 0.5555555555555556,
        'yes': 0.7777777777777778
      }
}

Result: 
yes  ==>  0.0720164609053
no  ==>  0.0411428571429

Hope it helps in better understanding the problem

peace

How do you import classes in JSP?

FYI - if you are importing a List into a JSP, chances are pretty good that you are violating MVC principles. Take a few hours now to read up on the MVC approach to web app development (including use of taglibs) - do some more googling on the subject, it's fascinating and will definitely help you write better apps.

If you are doing anything more complicated than a single JSP displaying some database results, please consider using a framework like Spring, Grails, etc... It will absolutely take you a bit more effort to get going, but it will save you so much time and effort down the road that I really recommend it. Besides, it's cool stuff :-)

Passing parameters from jsp to Spring Controller method

Your controller method should be like this:

@RequestMapping(value = " /<your mapping>/{id}", method=RequestMethod.GET)
public String listNotes(@PathVariable("id")int id,Model model) {
    Person person = personService.getCurrentlyAuthenticatedUser();
    int id = 2323;  // Currently passing static values for testing
    model.addAttribute("person", new Person());
    model.addAttribute("listPersons", this.personService.listPersons());
    model.addAttribute("listNotes",this.notesService.listNotesBySectionId(id,person));
    return "note";
}

Use the id in your code, call the controller method from your JSP as:

/{your mapping}/{your id}

UPDATE:

Change your jsp code to:

<c:forEach items="${listNotes}" var="notices" varStatus="status">
    <tr>
        <td>${notices.noticesid}</td>
        <td>${notices.notetext}</td>
        <td>${notices.notetag}</td>
        <td>${notices.notecolor}</td>
        <td>${notices.sectionid}</td>
        <td>${notices.canvasid}</td>
        <td>${notices.canvasnName}</td>
        <td>${notices.personid}</td>
        <td><a href="<c:url value='/editnote/${listNotes[status.index].noticesid}' />" >Edit</a></td>
        <td><a href="<c:url value='/removenote/${listNotes[status.index].noticesid}' />" >Delete</a></td>
    </tr>
</c:forEach>

Oracle SQL - DATE greater than statement

As your query string is a literal, and assuming your dates are properly stored as DATE you should use date literals:

SELECT * FROM OrderArchive
WHERE OrderDate <= DATE '2015-12-31'

If you want to use TO_DATE (because, for example, your query value is not a literal), I suggest you to explicitly set the NLS_DATE_LANGUAGE parameter as you are using US abbreviated month names. That way, it won't break on some localized Oracle Installation:

SELECT * FROM OrderArchive
WHERE OrderDate <= to_date('31 Dec 2014', 'DD MON YYYY',
                           'NLS_DATE_LANGUAGE = American');

What is the meaning of polyfills in HTML5?

Here are some high level thoughts and info that might help, aside from the other answers.

Pollyfills are like a compatability patch for specific browsers. Shims are changes to specific arguments. Fallbacks can be used if say a @mediaquery is not compatible with a browser.

It kind of depends on the requirements of what your app/website needs to be compatible with.

You cna check this site out for compatability of specific libraries with specific browsers. https://caniuse.com/

CSS3 Spin Animation

For the guys who still search some cool and easy spinner, we have multiple exemples of spinner on fontawesome site : https://fontawesome.com/v4.7.0/examples/

You just have to inspect the spinner you want with your debugger and copy the css styles.

How to remove/delete a large file from commit history in Git repository?

According to GitHub Documentation, just follow these steps:

  1. Get rid of the large file

Option 1: You don't want to keep the large file:

rm path/to/your/large/file        # delete the large file

Option 2: You want to keep the large file into an untracked directory

mkdir large_files                       # create directory large_files
touch .gitignore                        # create .gitignore file if needed
'/large_files/' >> .gitignore           # untrack directory large_files
mv path/to/your/large/file large_files/ # move the large file into the untracked directory
  1. Save your changes
git add path/to/your/large/file   # add the deletion to the index
git commit -m 'delete large file' # commit the deletion
  1. Remove the large file from all commits
git filter-branch --force --index-filter \
  "git rm --cached --ignore-unmatch path/to/your/large/file" \
  --prune-empty --tag-name-filter cat -- --all
git push <remote> <branch>

What is the iPad user agent?

From the simulator, in iPad mode:

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_5_8; en-us) AppleWebKit/531.9 (KHTML, like Gecko) Version/4.0.3 Safari/531.9 (this is for 3.2 beta 1)

Mozilla/5.0 (iPad; U; CPU OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.10 (KHTML, like Gecko) Version/4.0.4 Mobile/7B334b Safari/531.21.10 (this is for 3.2 beta 3)

and in iPhone mode:

Mozilla/5.0 (iPhone; U; CPU iPhone OS 3_2 like Mac OS X; en-us) AppleWebKit/531.21.20 (KHTML, like Gecko) Mobile/7B298g

I don't know how reliable the simulator is, but it seems you can't detect whether the device is iPad just from the user-agent string.

(Note: I'm on Snow Leopard which the User Agent string for Safari is

Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_2; en-us) AppleWebKit/531.21.8 (KHTML, like Gecko) Version/4.0.4 Safari/531.21.10

)

Laravel 4 with Sentry 2 add user to a group on Registration

Somehow, where you are using Sentry, you're not using its Facade, but the class itself. When you call a class through a Facade you're not really using statics, it's just looks like you are.

Do you have this:

use Cartalyst\Sentry\Sentry; 

In your code?

Ok, but if this line is working for you:

$user = $this->sentry->register(array(     'username' => e($data['username']),     'email' => e($data['email']),      'password' => e($data['password'])     )); 

So you already have it instantiated and you can surely do:

$adminGroup = $this->sentry->findGroupById(5); 

error: expected declaration or statement at end of input in c

Normally that error occurs when a } was missed somewhere in the code, for example:

void mi_start_curr_serv(void){
    #if 0
    //stmt
    #endif

would fail with this error due to the missing } at the end of the function. The code you posted doesn't have this error, so it is likely coming from some other part of your source.

input file appears to be a text format dump. Please use psql

if you use pg_dump with -Fp to backup in plain text format, use following command:

cat db.txt | psql dbname

to copy all data to your database with name dbname

Is it wrong to place the <script> tag after the </body> tag?

Modern browsers will take script tags in the body like so:

<body>
    <script src="scripts/main.js"></script>
</body>

Basically, it means that the script will be loaded once the page has finished, which may be useful in certain cases (namely DOM manipulation). However, I highly recommend you take the same script and put it in the head tag with "defer", as it will give the same effect.

<head>
    <script src="scripts/main.js" defer></script>
</head>

How to select and change value of table cell with jQuery?

I wanted to change the column value in a specific row. Thanks to above answers and after some serching able to come up with below,

var dataTable = $("#yourtableid");
var rowNumber = 0;  
var columnNumber= 2;   
dataTable[0].rows[rowNumber].cells[columnNumber].innerHTML = 'New Content';

Maven: How to run a .java file from command line passing arguments

Adding a shell script e.g. run.sh makes it much more easier:

#!/usr/bin/env bash
export JAVA_PROGRAM_ARGS=`echo "$@"`
mvn exec:java -Dexec.mainClass="test.Main" -Dexec.args="$JAVA_PROGRAM_ARGS"

Then you are able to execute:

./run.sh arg1 arg2 arg3

Reading/Writing a MS Word file in PHP

even i'm working on same kind of project [An Onlinw Word Processor]! But i've choosen c#.net and ASP.net. But through the survey i did; i got to know that

By Using Open XML SDK and VSTO [Visual Studio Tools For Office]

we may easily work with a word file manipulate them and even convert internally to different into several formats such as .odt,.pdf,.docx etc..

So, goto msdn.microsoft.com and be thorough about the office development tab. Its the easiest way to do this as all functions we need to implement are already available in .net!!

But as u want to do ur project in PHP, u can do it in Visual Studio and .net as PHP is also one of the .net Compliant Language!!

How to subtract X days from a date using Java calendar?

Taken from the docs here:

Adds or subtracts the specified amount of time to the given calendar field, based on the calendar's rules. For example, to subtract 5 days from the current time of the calendar, you can achieve it by calling:

Calendar calendar = Calendar.getInstance(); // this would default to now
calendar.add(Calendar.DAY_OF_MONTH, -5).

How to add content to html body using JS?

You're probably using

document.getElementById('element').innerHTML = "New content"

Try this instead:

document.getElementById('element').innerHTML += "New content"

Or, preferably, use DOM Manipulation:

document.getElementById('element').appendChild(document.createElement("div"))

Dom manipulation would be preferred compared to using innerHTML, because innerHTML simply dumps a string into the document. The browser will have to reparse the entire document to get it's stucture.

Variable might not have been initialized error

You declared them at the start of the method, but you never initialized them. Initializing would be setting them equal to a value, such as:

int a = 0;
int b = 0;

How to display a date as iso 8601 format with PHP

Using the DateTime class available in PHP version 5.2 it would be done like this:

$datetime = new DateTime('17 Oct 2008');
echo $datetime->format('c');

See it in action

As of PHP 5.4 you can do this as a one-liner:

echo (new DateTime('17 Oct 2008'))->format('c');

How to get year and month from a date - PHP

I personally prefer using this shortcut. The output will still be the same, but you don't need to store the month and year in separate variables

$dateValue = '2012-01-05';
$formattedValue = date("F Y", strtotime($dateValue));
echo $formattedValue; //Output should be January 2012

A little side note on using this trick, you can use comma's to separate the month and year like so:

$formattedValue = date("F, Y", strtotime($dateValue));
echo $formattedValue //Output should be January, 2012

I get conflicting provisioning settings error when I try to archive to submit an iOS app

I opened the project file in a text editor "Atom" then I searched for the provisioning profile id and deleted it.

How to write both h1 and h2 in the same line?

In many cases,

display:inline;

is enough.

But in some cases, you have to add following:

clear:none;

Encode URL in JavaScript?

You should not use encodeURIComponent() directly.

Take a look at RFC3986: Uniform Resource Identifier (URI): Generic Syntax

sub-delims = "!" / "$" / "&" / "'" / "(" / ")" / "*" / "+" / "," / ";" / "="

The purpose of reserved characters is to provide a set of delimiting characters that are distinguishable from other data within a URI.

These reserved characters from the URI definition in RFC3986 ARE NOT escaped by encodeURIComponent().

MDN Web Docs: encodeURIComponent()

To be more stringent in adhering to RFC 3986 (which reserves !, ', (, ), and *), even though these characters have no formalized URI delimiting uses, the following can be safely used:

Use the MDN Web Docs function...

function fixedEncodeURIComponent(str) {
  return encodeURIComponent(str).replace(/[!'()*]/g, function(c) {
    return '%' + c.charCodeAt(0).toString(16);
  });
}

Deserializing a JSON file with JavaScriptSerializer()

Assuming you don't want to create another class, you can always let the deserializer give you a dictionary of key-value-pairs, like so:

string s = //{ "user" : {    "id" : 12345,    "screen_name" : "twitpicuser"}};
var serializer = new JavaScriptSerializer();
var result = serializer.DeserializeObject(s);

You'll get back something, where you can do:

var userId = int.Parse(result["user"]["id"]); // or (int)result["user"]["id"] depending on how the JSON is serialized.
// etc.

Look at result in the debugger to see, what's in there.

How to give a time delay of less than one second in excel vba?

I found this on another site not sure if it works or not.

Application.Wait Now + 1/(24*60*60.0*2)

the numerical value 1 = 1 day

1/24 is one hour

1/(24*60) is one minute

so 1/(24*60*60*2) is 1/2 second

You need to use a decimal point somewhere to force a floating point number

Source

Not sure if this will work worth a shot for milliseconds

Application.Wait (Now + 0.000001) 

How to select Multiple images from UIImagePickerController

You can't use UIImagePickerController, but you can use a custom image picker. I think ELCImagePickerController is the best option, but here are some other libraries you could use:

Objective-C
1. ELCImagePickerController
2. WSAssetPickerController
3. QBImagePickerController
4. ZCImagePickerController
5. CTAssetsPickerController
6. AGImagePickerController
7. UzysAssetsPickerController
8. MWPhotoBrowser
9. TSAssetsPickerController
10. CustomImagePicker
11. InstagramPhotoPicker
12. GMImagePicker
13. DLFPhotosPicker
14. CombinationPickerController
15. AssetPicker
16. BSImagePicker
17. SNImagePicker
18. DoImagePickerController
19. grabKit
20. IQMediaPickerController
21. HySideScrollingImagePicker
22. MultiImageSelector
23. TTImagePicker
24. SelectImages
25. ImageSelectAndSave
26. imagepicker-multi-select
27. MultiSelectImagePickerController
28. YangMingShan(Yahoo like image selector)
29. DBAttachmentPickerController
30. BRImagePicker
31. GLAssetGridViewController
32. CreolePhotoSelection

Swift
1. LimPicker (Similar to WhatsApp's image picker)
2. RMImagePicker
3. DKImagePickerController
4. BSImagePicker
5. Fusuma(Instagram like image selector)
6. YangMingShan(Yahoo like image selector)
7. NohanaImagePicker
8. ImagePicker
9. OpalImagePicker
10. TLPhotoPicker
11. AssetsPickerViewController
12. Alerts-and-pickers/Telegram Picker

Thanx to @androidbloke,
I have added some library that I know for multiple image picker in swift.
Will update list as I find new ones.
Thank You.

How to check if an option is selected?

UPDATE

A more direct jQuery method to the option selected would be:

var selected_option = $('#mySelectBox option:selected');

Answering the question .is(':selected') is what you are looking for:

$('#mySelectBox option').each(function() {
    if($(this).is(':selected')) ...

The non jQuery (arguably best practice) way to do it would be:

$('#mySelectBox option').each(function() {
    if(this.selected) ...

Although, if you are just looking for the selected value try:

$('#mySelectBox').val()

If you are looking for the selected value's text do:

$('#mySelectBox option').filter(':selected').text();

Check out: http://api.jquery.com/selected-selector/

Next time look for duplicate SO questions:

Get current selected option or Set selected option or How to get $(this) selected option in jQuery? or option[selected=true] doesn't work

c# - How to get sum of the values from List?

Use Sum()

 List<string> foo = new List<string>();
 foo.Add("1");
 foo.Add("2");
 foo.Add("3");
 foo.Add("4");

 Console.Write(foo.Sum(x => Convert.ToInt32(x)));

Prints:

10

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

Bud, disable selinux or add the following to your RedHat/CentOS Server:

setsebool -P httpd_can_network_connect_db 1
setsebool -P httpd_can_network_connect 1

Best always!

How can I check what version/edition of Visual Studio is installed programmatically?

An updated answer to this question would be the following :

"C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe" -latest -property productId

Resolves to 2019

"C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe" -latest -property catalog_productLineVersion

Resolves to Microsoft.VisualStudio.Product.Professional

How can I plot data with confidence intervals?

Here is a solution using functions plot(), polygon() and lines().

 set.seed(1234)
 df <- data.frame(x =1:10,
                 F =runif(10,1,2),
                 L =runif(10,0,1),
                 U =runif(10,2,3))


 plot(df$x, df$F, ylim = c(0,4), type = "l")
 #make polygon where coordinates start with lower limit and 
 # then upper limit in reverse order
 polygon(c(df$x,rev(df$x)),c(df$L,rev(df$U)),col = "grey75", border = FALSE)
 lines(df$x, df$F, lwd = 2)
 #add red lines on borders of polygon
 lines(df$x, df$U, col="red",lty=2)
 lines(df$x, df$L, col="red",lty=2)

enter image description here

Now use example data provided by OP in another question:

   Lower <- c(0.418116841, 0.391011834, 0.393297710,
        0.366144073,0.569956636,0.224775521,0.599166016,0.512269587,
        0.531378573, 0.311448219, 0.392045751,0.153614913, 0.366684097,
        0.161100849,0.700274810,0.629714150, 0.661641288, 0.533404093,
        0.412427559, 0.432905333, 0.525306427,0.224292061,
        0.28893064,0.099543648, 0.342995605,0.086973739,0.289030388,
        0.081230826,0.164505624, -0.031290586,0.148383474,0.070517523,0.009686605,
        -0.052703529,0.475924192,0.253382210, 0.354011010,0.130295355,0.102253218,
        0.446598823,0.548330752,0.393985810,0.481691632,0.111811248,0.339626541,
        0.267831909,0.133460254,0.347996621,0.412472322,0.133671128,0.178969601,0.484070587,
        0.335833224,0.037258467, 0.141312363,0.361392799,0.129791998,
        0.283759439,0.333893418,0.569533076,0.385258093,0.356201955,0.481816148,
        0.531282473,0.273126565,0.267815691,0.138127486,0.008865700,0.018118398,0.080143484,
        0.117861634,0.073697418,0.230002398,0.105855042,0.262367348,0.217799352,0.289108011,
        0.161271889,0.219663224,0.306117717,0.538088622,0.320711912,0.264395149,0.396061543,
        0.397350946,0.151726970,0.048650180,0.131914718,0.076629840,0.425849394,
        0.068692279,0.155144797,0.137939059,0.301912657,-0.071415593,-0.030141781,0.119450922,
        0.312927614,0.231345972)

 Upper.limit <- c(0.6446223,0.6177311, 0.6034427, 0.5726503,
      0.7644718, 0.4585430, 0.8205418, 0.7154043,0.7370033,
      0.5285199, 0.5973728, 0.3764209, 0.5818298,
      0.3960867,0.8972357, 0.8370151, 0.8359921, 0.7449118,
      0.6152879, 0.6200704, 0.7041068, 0.4541011, 0.5222653,
      0.3472364, 0.5956551, 0.3068065, 0.5112895, 0.3081448,
      0.3745473, 0.1931089, 0.3890704, 0.3031025, 0.2472591,
      0.1976092, 0.6906118, 0.4736644, 0.5770463, 0.3528607,
      0.3307651, 0.6681629, 0.7476231, 0.5959025, 0.7128883,
      0.3451623, 0.5609742, 0.4739216, 0.3694883, 0.5609220,
      0.6343219, 0.3647751, 0.4247147, 0.6996334, 0.5562876,
      0.2586490, 0.3750040, 0.5922248, 0.3626322, 0.5243285,
      0.5548211, 0.7409648, 0.5820070, 0.5530232, 0.6863703,
      0.7206998, 0.4952387, 0.4993264, 0.3527727, 0.2203694,
      0.2583149, 0.3035342, 0.3462009, 0.3003602, 0.4506054,
      0.3359478, 0.4834151, 0.4391330, 0.5273411, 0.3947622,
      0.4133769, 0.5288060, 0.7492071, 0.5381701, 0.4825456,
      0.6121942, 0.6192227, 0.3784870, 0.2574025, 0.3704140,
      0.2945623, 0.6532694, 0.2697202, 0.3652230, 0.3696383,
      0.5268808, 0.1545602, 0.2221450, 0.3553377, 0.5204076,
      0.3550094)

  Fitted.values<- c(0.53136955, 0.50437146, 0.49837019,
  0.46939721, 0.66721423, 0.34165926, 0.70985388, 0.61383696,
  0.63419092, 0.41998407, 0.49470927, 0.26501789, 0.47425695,
  0.27859380, 0.79875525, 0.73336461, 0.74881668, 0.63915795,
  0.51385774, 0.52648789, 0.61470661, 0.33919656, 0.40559797,
  0.22339000, 0.46932536, 0.19689011, 0.40015996, 0.19468781,
  0.26952645, 0.08090917, 0.26872696, 0.18680999, 0.12847285,
  0.07245286, 0.58326799, 0.36352329, 0.46552867, 0.24157804,
  0.21650915, 0.55738088, 0.64797691, 0.49494416, 0.59728999,
  0.22848680, 0.45030036, 0.37087676, 0.25147426, 0.45445930,
  0.52339711, 0.24922310, 0.30184215, 0.59185198, 0.44606040,
  0.14795374, 0.25815819, 0.47680880, 0.24621212, 0.40404398,
  0.44435727, 0.65524894, 0.48363255, 0.45461258, 0.58409323,
  0.62599114, 0.38418264, 0.38357103, 0.24545011, 0.11461756,
  0.13821664, 0.19183886, 0.23203127, 0.18702881, 0.34030391,
  0.22090140, 0.37289121, 0.32846615, 0.40822456, 0.27801706,
  0.31652008, 0.41746184, 0.64364785, 0.42944100, 0.37347037,
  0.50412786, 0.50828681, 0.26510696, 0.15302635, 0.25116438,
  0.18559609, 0.53955941, 0.16920626, 0.26018389, 0.25378867,
  0.41439675, 0.04157232, 0.09600163, 0.23739430, 0.41666762,
  0.29317767)

Assemble into a data frame (no x provided, so using indices)

 df2 <- data.frame(x=seq(length(Fitted.values)),
                    fit=Fitted.values,lwr=Lower,upr=Upper.limit)
 plot(fit~x,data=df2,ylim=range(c(df2$lwr,df2$upr)))
 #make polygon where coordinates start with lower limit and then upper limit in reverse order
 with(df2,polygon(c(x,rev(x)),c(lwr,rev(upr)),col = "grey75", border = FALSE))
 matlines(df2[,1],df2[,-1],
          lwd=c(2,1,1),
          lty=1,
          col=c("black","red","red"))

enter image description here

How to normalize a histogram in MATLAB?

My answer to this is the same as in an answer to your earlier question. For a probability density function, the integral over the entire space is 1. Dividing by the sum will not give you the correct density. To get the right density, you must divide by the area. To illustrate my point, try the following example.

[f, x] = hist(randn(10000, 1), 50); % Create histogram from a normal distribution.
g = 1 / sqrt(2 * pi) * exp(-0.5 * x .^ 2); % pdf of the normal distribution

% METHOD 1: DIVIDE BY SUM
figure(1)
bar(x, f / sum(f)); hold on
plot(x, g, 'r'); hold off

% METHOD 2: DIVIDE BY AREA
figure(2)
bar(x, f / trapz(x, f)); hold on
plot(x, g, 'r'); hold off

You can see for yourself which method agrees with the correct answer (red curve).

enter image description here

Another method (more straightforward than method 2) to normalize the histogram is to divide by sum(f * dx) which expresses the integral of the probability density function, i.e.

% METHOD 3: DIVIDE BY AREA USING sum()
figure(3)
dx = diff(x(1:2))
bar(x, f / sum(f * dx)); hold on
plot(x, g, 'r'); hold off

How do I access ViewBag from JS

try: var cc = @Html.Raw(Json.Encode(ViewBag.CC)

Redirect stderr to stdout in C shell

The csh shell has never been known for its extensive ability to manipulate file handles in the redirection process.

You can redirect both standard output and error to a file with:

xxx >& filename

but that's not quite what you were after, redirecting standard error to the current standard output.


However, if your underlying operating system exposes the standard output of a process in the file system (as Linux does with /dev/stdout), you can use that method as follows:

xxx >& /dev/stdout

This will force both standard output and standard error to go to the same place as the current standard output, effectively what you have with the bash redirection, 2>&1.

Just keep in mind this isn't a csh feature. If you run on an operating system that doesn't expose standard output as a file, you can't use this method.


However, there is another method. You can combine the two streams into one if you send it to a pipeline with |&, then all you need to do is find a pipeline component that writes its standard input to its standard output. In case you're unaware of such a thing, that's exactly what cat does if you don't give it any arguments. Hence, you can achieve your ends in this specific case with:

xxx |& cat

Of course, there's also nothing stopping you from running bash (assuming it's on the system somewhere) within a csh script to give you the added capabilities. Then you can use the rich redirections of that shell for the more complex cases where csh may struggle.

Let's explore this in more detail. First, create an executable echo_err that will write a string to stderr:

#include <stdio.h>
int main (int argc, char *argv[]) {
    fprintf (stderr, "stderr (%s)\n", (argc > 1) ? argv[1] : "?");
    return 0;
}

Then a control script test.csh which will show it in action:

#!/usr/bin/csh

ps -ef ; echo ; echo $$ ; echo

echo 'stdout (csh)'
./echo_err csh

bash -c "( echo 'stdout (bash)' ; ./echo_err bash ) 2>&1"

The echo of the PID and ps are simply so you can ensure it's csh running this script. When you run this script with:

./test.csh >test.out 2>test.err

(the initial redirection is set up by bash before csh starts running the script), and examine the out/err files, you see:

test.out:
    UID     PID    PPID  TTY        STIME     COMMAND
    pax    5708    5364  cons0      11:31:14  /usr/bin/ps
    pax    5364    7364  cons0      11:31:13  /usr/bin/tcsh
    pax    7364       1  cons0      10:44:30  /usr/bin/bash

    5364

    stdout (csh)
    stdout (bash)
    stderr (bash)

test.err:
    stderr (csh)

You can see there that the test.csh process is running in the C shell, and that calling bash from within there gives you the full bash power of redirection.

The 2>&1 in the bash command quite easily lets you redirect standard error to the current standard output (as desired) without prior knowledge of where standard output is currently going.

How can I clear or empty a StringBuilder?

I think many of the answers here may be missing a quality method included in StringBuilder: .delete(int start, [int] end). I know this is a late reply; however, this should be made known (and explained a bit more thoroughly).

Let's say you have a StringBuilder table - which you wish to modify, dynamically, throughout your program (one I am working on right now does this), e.g.

StringBuilder table = new StringBuilder();

If you are looping through the method and alter the content, use the content, then wish to discard the content to "clean up" the StringBuilder for the next iteration, you can delete it's contents, e.g.

table.delete(int start, int end). 

start and end being the indices of the chars you wish to remove. Don't know the length in chars and want to delete the whole thing?

table.delete(0, table.length());

NOW, for the kicker. StringBuilders, as mentioned previously, take a lot of overhead when altered frequently (and can cause safety issues with regard to threading); therefore, use StringBuffer - same as StringBuilder (with a few exceptions) - if your StringBuilder is used for the purpose of interfacing with the user.

Easiest way to convert int to string in C++

Using the plain standard stdio header, you can cast the integer over sprintf into a buffer, like so:

#include <stdio.h>
int main()
  {
  int x=23;
  char y[2]; //the output buffer
  sprintf(y,"%d",x);
  printf("%s",y)
  }

Remember to take care of your buffer size according to your needs [the string output size]

Select from table by knowing only date without time (ORACLE)

Simply use this one:

select * from t1 where to_date(date_column)='8/3/2010'

Find mouse position relative to element

I had to get the cursor position inside a very wide div with scrollbar. The objective was to drag elements to any position of the div.

To get the mouse position on a far away position deep in the scrolling.

$('.canvas').on('mousemove', function(e){
    $(dragElement).parent().css('top', e.currentTarget.scrollTop + e.originalEvent.clientY );
    $(dragElement).parent().css('left', e.currentTarget.scrollLeft + e.originalEvent.clientX )
});

Check if not nil and not empty in Rails shortcut?

You can use .present? which comes included with ActiveSupport.

@city = @user.city.present?
# etc ...

You could even write it like this

def show
  %w(city state bio contact twitter mail).each do |attr|
    instance_variable_set "@#{attr}", @user[attr].present?
  end
end

It's worth noting that if you want to test if something is blank, you can use .blank? (this is the opposite of .present?)

Also, don't use foo == nil. Use foo.nil? instead.

iOS download and save image inside app

That's the main concept. Have fun ;)

NSURL *url = [NSURL URLWithString:@"http://example.com/yourImage.png"];
NSData *data = [NSData dataWithContentsOfURL:url];
NSString *path = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
path = [path stringByAppendingString:@"/yourLocalImage.png"];
[data writeToFile:path atomically:YES];

How to properly -filter multiple strings in a PowerShell copy script

-Filter only accepts a single string. -Include accepts multiple values, but qualifies the -Path argument. The trick is to append \* to the end of the path, and then use -Include to select multiple extensions. BTW, quoting strings is unnecessary in cmdlet arguments unless they contain spaces or shell special characters.

Get-ChildItem $originalPath\* -Include *.gif, *.jpg, *.xls*, *.doc*, *.pdf*, *.wav*, .ppt*

Note that this will work regardless of whether $originalPath ends in a backslash, because multiple consecutive backslashes are interpreted as a single path separator. For example, try:

Get-ChildItem C:\\\\\Windows

PHP & localStorage;

localStorage is something that is kept on the client side. There is no data transmitted to the server side.

You can only get the data with JavaScript and you can send it to the server side with Ajax.

Importing a function from a class in another file?

from FOLDER_NAME import FILENAME
from FILENAME import CLASS_NAME FUNCTION_NAME

FILENAME is w/o the suffix

How to remove MySQL root password

You need to set the password for root@localhost to be blank. There are two ways:

  1. The MySQL SET PASSWORD command:

    SET PASSWORD FOR root@localhost=PASSWORD('');
    
  2. Using the command-line mysqladmin tool:

    mysqladmin -u root -pType_in_your_current_password_here password ''
    

ImproperlyConfigured: You must either define the environment variable DJANGO_SETTINGS_MODULE or call settings.configure() before accessing settings

I figured that the DJANGO_SETTINGS_MODULE had to be set some way, so I looked at the documentation (link updated) and found:

export DJANGO_SETTINGS_MODULE=mysite.settings

Though that is not enough if you are running a server on heroku, you need to specify it there, too. Like this:

heroku config:set DJANGO_SETTINGS_MODULE=mysite.settings --account <your account name> 

In my specific case I ran these two and everything worked out:

export DJANGO_SETTINGS_MODULE=nirla.settings
heroku config:set DJANGO_SETTINGS_MODULE=nirla.settings --account personal

Edit

I would also like to point out that you have to re-do this every time you close or restart your virtual environment. Instead, you should automate the process by going to venv/bin/activate and adding the line: set DJANGO_SETTINGS_MODULE=mysite.settings to the bottom of the code. From now on every time you activate the virtual environment, you will be using that app's settings.

How to resolve compiler warning 'implicit declaration of function memset'

memset requires you to import the header string.h file. So just add the following header

#include <string.h>
...

Viewing local storage contents on IE

Edge (as opposed to IE11) has a better UI for Local storage / Session storage and cookies:

  • Open Dev tools (F12)
  • Go to Debugger tab
  • Click the folder icon to show a list of resources - opens in a separate tab

Dev tools screenshot

GitLab git user password

The Solution from https://github.com/gitlabhq/gitlab-shell/issues/46 worked for me.

By setting the permissions:

chmod 700 /home/git/.ssh
chmod 600 /home/git/.ssh/authorized_keys

password prompt disappears.

How do I abort the execution of a Python script?

If the entire program should stop use sys.exit() otherwise just use an empty return.

What does "Content-type: application/json; charset=utf-8" really mean?

Note that IETF RFC4627 has been superseded by IETF RFC7158. In section [8.1] it retracts the text cited by @Drew earlier by saying:

Implementations MUST NOT add a byte order mark to the beginning of a JSON text.

Python requests - print entire http request (raw)?

Here is a code, which makes the same, but with response headers:

import socket
def patch_requests():
    old_readline = socket._fileobject.readline
    if not hasattr(old_readline, 'patched'):
        def new_readline(self, size=-1):
            res = old_readline(self, size)
            print res,
            return res
        new_readline.patched = True
        socket._fileobject.readline = new_readline
patch_requests()

I spent a lot of time searching for this, so I'm leaving it here, if someone needs.

How to represent empty char in Java Character class

As Character is a class deriving from Object, you can assign null as "instance":

Character myChar = null;

Problem solved ;)

What is cURL in PHP?

CURL in PHP:

Summary:

The curl_exec command in PHP is a bridge to use curl from console. curl_exec makes it easy to quickly and easily do GET/POST requests, receive responses from other servers like JSON and download files.

Warning, Danger:

curl is evil and dangerous if used improperly because it is all about getting data from out there in the internet. Someone can get between your curl and the other server and inject a rm -rf / into your response, and then why am I dropped to a console and ls -l doesn't even work anymore? Because you mis underestimated the dangerous power of curl. Don't trust anything that comes back from curl to be safe, even if you are talking to your own servers. You could be pulling back malware to relieve fools of their wealth.

Examples:

These were done on Ubuntu 12.10

  1. Basic curl from the commandline:

    el@apollo:/home/el$ curl http://i.imgur.com/4rBHtSm.gif > mycat.gif
      % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                     Dload  Upload   Total   Spent    Left  Speed
    100  492k  100  492k    0     0  1077k      0 --:--:-- --:--:-- --:--:-- 1240k
    

    Then you can open up your gif in firefox:

    firefox mycat.gif
    

    Glorious cats evolving Toxoplasma gondii to cause women to keep cats around and men likewise to keep the women around.

  2. cURL example get request to hit google.com, echo to the commandline:

    This is done through the phpsh terminal:

    php> $ch = curl_init();
    
    php> curl_setopt($ch, CURLOPT_URL, 'http://www.google.com');
    
    php> curl_exec($ch);
    

    Which prints and dumps a mess of condensed html and javascript (from google) to the console.

  3. cURL example put the response text into a variable:

    This is done through the phpsh terminal:

    php> $ch = curl_init();
    
    php> curl_setopt($ch, CURLOPT_URL, 'http://i.imgur.com/wtQ6yZR.gif');
    
    php> curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    
    php> $contents = curl_exec($ch);
    
    php> echo $contents;
    

    The variable now contains the binary which is an animated gif of a cat, possibilities are infinite.

  4. Do a curl from within a PHP file:

    Put this code in a file called myphp.php:

    <?php
      $curl_handle=curl_init();
      curl_setopt($curl_handle,CURLOPT_URL,'http://www.google.com');
      curl_setopt($curl_handle,CURLOPT_CONNECTTIMEOUT,2);
      curl_setopt($curl_handle,CURLOPT_RETURNTRANSFER,1);
      $buffer = curl_exec($curl_handle);
      curl_close($curl_handle);
      if (empty($buffer)){
          print "Nothing returned from url.<p>";
      }
      else{
          print $buffer;
      }
    ?>
    

    Then run it via commandline:

    php < myphp.php
    

    You ran myphp.php and executed those commands through the php interpreter and dumped a ton of messy html and javascript to screen.

    You can do GET and POST requests with curl, all you do is specify the parameters as defined here: Using curl to automate HTTP jobs

Reminder of danger:

Be careful dumping curl output around, if any of it gets interpreted and executed, your box is owned and your credit card info will be sold to third parties and you'll get a mysterious $900 charge from an Alabama one-man flooring company that's a front for overseas credit card fraud crime ring.

What's the difference between primitive and reference types?

these are primitive data types

  • boolean
  • character
  • byte
  • short
  • integer
  • long
  • float
  • double

saved in stack in the memory which is managed memory on the other hand object data type or reference data type stored in head in the memory managed by GC

this is the most important difference

Different font size of strings in the same TextView

In case you want to avoid too much confusion for your translators, I've come up with a way to have just a placeholder in the strings, which will be handled in code.

So, supposed you have this in the strings:

    <string name="test">
        <![CDATA[
        We found %1$s items]]>
    </string>

And you want the placeholder text to have a different size and color, you can use this:

        val textToPutAsPlaceHolder = "123"
        val formattedStr = getString(R.string.test, "$textToPutAsPlaceHolder<bc/>")
        val placeHolderTextSize = resources.getDimensionPixelSize(R.dimen.some_text_size)
        val placeHolderTextColor = ContextCompat.getColor(this, R.color.design_default_color_primary_dark)
        val textToShow = HtmlCompat.fromHtml(formattedStr, HtmlCompat.FROM_HTML_MODE_LEGACY, null, object : Html.TagHandler {
            var start = 0
            override fun handleTag(opening: Boolean, tag: String, output: Editable, xmlReader: XMLReader) {
                when (tag) {
                    "bc" -> if (!opening) start = output.length - textToPutAsPlaceHolder.length
                    "html" -> if (!opening) {
                        output.setSpan(AbsoluteSizeSpan(placeHolderTextSize), start, start + textToPutAsPlaceHolder.length, 0)
                        output.setSpan(ForegroundColorSpan(placeHolderTextColor), start, start + textToPutAsPlaceHolder.length, 0)
                    }
                }
            }
        })
        textView.text = textToShow

And the result:

enter image description here

Stateless vs Stateful

Money transfered online form one account to another account is stateful, because the receving account has information about the sender. Handing over cash from a person to another person, this transaction is statless, because after cash is recived the identity of the giver is not there with the cash.

Extracting substrings in Go

To avoid a panic on a zero length input, wrap the truncate operation in an if

input, _ := src.ReadString('\n')
var inputFmt string
if len(input) > 0 {
    inputFmt = input[:len(input)-1]
}
// Do something with inputFmt

Creating temporary files in Android

You can use the cache dir using context.getCacheDir().

File temp=File.createTempFile("prefix","suffix",context.getCacheDir());

How to Add a Dotted Underline Beneath HTML Text

You can try this method:

<h2 style="text-decoration: underline; text-underline-position: under; text-decoration-style: dotted">Hello World!</h2>

Please note that without text-underline-position: under; you still will have a dotted underline but this property will give it more breathing space.

This is assuming you want to embed everything inside an HTML file using inline styling and not to use a separate CSS file or tag.

onActivityResult is not being called in Fragment

Your code has a nested fragment. Calling super.onActivityForResult doesn't work

You don't want to modify every activity that your fragment can be called from and or make a work around calling every fragment in the fragment chain.

Here is one of many working solutions. create a fragment on the fly and wire it directly to the activity with the support fragment manager. Then call startActivityForResult from the newly created fragment.

private void get_UserEmail() {

    if (view == null) {
        return;
    }
    ((TextView) view.findViewById(R.id.tvApplicationUserName))
            .setText("Searching device for user accounts...");

    final FragmentManager fragManager = getActivity().getSupportFragmentManager();

    Fragment f = new Fragment() {
        @Override
        public void onAttach(Activity activity) {
            super.onAttach(activity);
            startActivityForResult(AccountPicker.newChooseAccountIntent(null, null,
                    new String[]{"com.google"}, false, null, null, null, null), REQUEST_CODE_PICK_ACCOUNT);
        }

        @Override
        public void onActivityResult(int requestCode, int resultCode,
                                     Intent data) {
            if (requestCode == REQUEST_CODE_PICK_ACCOUNT) {
                String mEmail = "";
                if (resultCode == Activity.RESULT_OK) {
                    if (data.hasExtra(AccountManager.KEY_ACCOUNT_NAME)) {
                        mEmail = data
                                .getStringExtra(AccountManager.KEY_ACCOUNT_NAME);
                    }
                }
                if (mActivity != null) {
                    GoPreferences.putString(mActivity, SettingApplication.USER_EMAIL, mEmail);
                }
                doUser();
            }
            super.onActivityResult(requestCode, resultCode, data);
            fragManager.beginTransaction().remove(this).commit();
        }
    };
    FragmentTransaction fragmentTransaction = fragManager
            .beginTransaction();
    fragmentTransaction.add(f, "xx" + REQUEST_CODE_PICK_ACCOUNT);
    fragmentTransaction.commit();
}

C++ equivalent of java's instanceof

Depending on what you want to do you could do this:

template<typename Base, typename T>
inline bool instanceof(const T*) {
    return std::is_base_of<Base, T>::value;
}

Use:

if (instanceof<BaseClass>(ptr)) { ... }

However, this purely operates on the types as known by the compiler.

Edit:

This code should work for polymorphic pointers:

template<typename Base, typename T>
inline bool instanceof(const T *ptr) {
    return dynamic_cast<const Base*>(ptr) != nullptr;
}

Example: http://cpp.sh/6qir

Write HTML file using Java

I would highly recommend you use a very simple templating language such as Freemarker

Promise.all().then() resolve?

Today NodeJS supports new async/await syntax. This is an easy syntax and makes the life much easier

async function process(promises) { // must be an async function
    let x = await Promise.all(promises);  // now x will be an array
    x = x.map( tmp => tmp * 10);              // proccessing the data.
}

const promises = [
   new Promise(resolve => setTimeout(resolve, 0, 1)),
   new Promise(resolve => setTimeout(resolve, 0, 2))
];

process(promises)

Learn more:

How to program a delay in Swift 3

//Runs function after x seconds

public static func runThisAfterDelay(seconds: Double, after: @escaping () -> Void) {
    runThisAfterDelay(seconds: seconds, queue: DispatchQueue.main, after: after)
}

public static func runThisAfterDelay(seconds: Double, queue: DispatchQueue, after: @escaping () -> Void) {
    let time = DispatchTime.now() + Double(Int64(seconds * Double(NSEC_PER_SEC))) / Double(NSEC_PER_SEC)
    queue.asyncAfter(deadline: time, execute: after)
}

//Use:-

runThisAfterDelay(seconds: x){
  //write your code here
}

JavaScript for detecting browser language preference

Update of year 2014.

Now there is a way to get Accept-Languages in Firefox and Chrome using navigator.languages (works in Chrome >= 32 and Firefox >= 32)

Also, navigator.language in Firefox these years reflects most preferred language of content, not language of UI. But since this notion is yet to be supported by other browsers, it is not very useful.

So, to get most preferred content language when possible, and use UI language as fallback:

navigator.languages
    ? navigator.languages[0]
    : (navigator.language || navigator.userLanguage)

git commit error: pathspec 'commit' did not match any file(s) known to git

I have encounter the same problem. my syntax has no problem. What I found is that I copied and pasted git commit -m "comments" from my note. I retype it, the command execute without issue. It turns out the - and " " are the problem when I copy paste to terminal.

Parse JSON in C#

Your data class doesn't match the JSON object. Use this instead:

[DataContract]
public class GoogleSearchResults
{
    [DataMember]
    public ResponseData responseData { get; set; }
}

[DataContract]
public class ResponseData
{
    [DataMember]
    public IEnumerable<Results> results { get; set; }
}

[DataContract]
public class Results
{
    [DataMember]
    public string unescapedUrl { get; set; }

    [DataMember]
    public string url { get; set; }

    [DataMember]
    public string visibleUrl { get; set; }

    [DataMember]
    public string cacheUrl { get; set; }

    [DataMember]
    public string title { get; set; }

    [DataMember]
    public string titleNoFormatting { get; set; }

    [DataMember]
    public string content { get; set; }
}

Also, you don't have to instantiate the class to get its type for deserialization:

public static T Deserialise<T>(string json)
{
    using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(json)))
    {
        var serialiser = new DataContractJsonSerializer(typeof(T));
        return (T)serialiser.ReadObject(ms);
    }
}

?: operator (the 'Elvis operator') in PHP

It evaluates to the left operand if the left operand is truthy, and the right operand otherwise.

In pseudocode,

foo = bar ?: baz;

roughly resolves to

foo = bar ? bar : baz;

or

if (bar) {
    foo = bar;
} else {
    foo = baz;
}

with the difference that bar will only be evaluated once.

You can also use this to do a "self-check" of foo as demonstrated in the code example you posted:

foo = foo ?: bar;

This will assign bar to foo if foo is null or falsey, else it will leave foo unchanged.

Some more examples:

<?php
    var_dump(5 ?: 0); // 5
    var_dump(false ?: 0); // 0
    var_dump(null ?: 'foo'); // 'foo'
    var_dump(true ?: 123); // true
    var_dump('rock' ?: 'roll'); // 'rock'
?>

By the way, it's called the Elvis operator.

Elvis operator

Where is Xcode's build folder?

~/Library/Developer/Xcode/DerivedData is now the default.
You can set the prefs in Xcode to allow projects to specify their build directories.

How can I tell AngularJS to "refresh"

The solution was to call...

$scope.$apply();

...in my jQuery event callback.

Add CSS3 transition expand/collapse

Here's a solution that doesn't use JS at all. It uses checkboxes instead.

You can hide the checkbox by adding this to your CSS:

.container input{
    display: none;
}

And then add some styling to make it look like a button.

Here's the source code that I modded.

Python - How to sort a list of lists by the fourth element in each list?

Use sorted() with a key as follows -

>>> unsorted_list = [['a','b','c','5','d'],['e','f','g','3','h'],['i','j','k','4','m']]
>>> sorted(unsorted_list, key = lambda x: int(x[3]))
[['e', 'f', 'g', '3', 'h'], ['i', 'j', 'k', '4', 'm'], ['a', 'b', 'c', '5', 'd']]

The lambda returns the fourth element of each of the inner lists and the sorted function uses that to sort those list. This assumes that int(elem) will not fail for the list.

Or use itemgetter (As Ashwini's comment pointed out, this method would not work if you have string representations of the numbers, since they are bound to fail somewhere for 2+ digit numbers)

>>> from operator import itemgetter
>>> sorted(unsorted_list, key = itemgetter(3))
[['e', 'f', 'g', '3', 'h'], ['i', 'j', 'k', '4', 'm'], ['a', 'b', 'c', '5', 'd']]

How do I use a Boolean in Python?

True ... and False obviously.

Otherwise, None evaluates to False, as does the integer 0 and also the float 0.0 (although I wouldn't use floats like that). Also, empty lists [], empty tuplets (), and empty strings '' or "" evaluate to False.

Try it yourself with the function bool():

bool([])
bool(['a value'])
bool('')
bool('A string')
bool(True)  # ;-)
bool(False)
bool(0)
bool(None)
bool(0.0)
bool(1)

etc..

Why use prefixes on member variables in C++ classes

I use m_ for member variables just to take advantage of Intellisense and related IDE-functionality. When I'm coding the implementation of a class I can type m_ and see the combobox with all m_ members grouped together.

But I could live without m_ 's without problem, of course. It's just my style of work.

How do I replace multiple spaces with a single space in C#?

string sentence = "This is a sentence with multiple    spaces";
RegexOptions options = RegexOptions.None;
Regex regex = new Regex("[ ]{2,}", options);     
sentence = regex.Replace(sentence, " ");

How to resolve git stash conflict without commit?

No problem there. A simple git reset HEAD is what you're looking for because it leaves your files as modified just like a non-conflicting git stash pop.

The only problem is that your conflicting files will still have the conflict tags and git will no longer report them as conflicting with the "both_modified" flag which is useful.

To prevent this, just resolve the conflicts (edit and fix the conflicting files) before running git reset HEAD and you're good to go...

At the end of this process your stash will remain in the queue, so just do a git stash drop to clear it up.

This just happened to me and googled this question, so the solution has been tested.

I think that's as clean as it gets...

How to get a Fragment to remove itself, i.e. its equivalent of finish()?

To Close a fragment while inside the same fragment

getActivity().onBackPressed();

Receiving "fatal: Not a git repository" when attempting to remote add a Git repo

You'll get this error if you try to use a Git command when your current working directory is not within a Git repository. That is because, by default, Git will look for a .git repository directory (inside of the project root?), as pointed out by my answer to "Git won't show log unless I am in the project directory":

According to the official Linux Kernel Git documentation, GIT_DIR is [an environment variable] set to look for a .git directory (in the current working directory?) by default:

If the GIT_DIR environment variable is set then it specifies a path to use instead of the default .git for the base of the repository.

You'll either need to cd into the repository/working copy, or you didn't initialize or clone a repository in the first place, in which case you need to initialize a repo in the directory where you want to place the repo:

git init

or clone a repository

git clone <remote-url>
cd <repository>

Compare DATETIME and DATE ignoring time portion

Use the CAST to the new DATE data type in SQL Server 2008 to compare just the date portion:

IF CAST(DateField1 AS DATE) = CAST(DateField2 AS DATE)

How can I render Partial views in asp.net mvc 3?

Create your partial view something like:

@model YourModelType
<div>
  <!-- HTML to render your object -->
</div>

Then in your view use:

@Html.Partial("YourPartialViewName", Model)

If you do not want a strongly typed partial view remove the @model YourModelType from the top of the partial view and it will default to a dynamic type.

Update

The default view engine will search for partial views in the same folder as the view calling the partial and then in the ~/Views/Shared folder. If your partial is located in a different folder then you need to use the full path. Note the use of ~/ in the path below.

@Html.Partial("~/Views/Partials/SeachResult.cshtml", Model)

invalid use of incomplete type

The reason is that when instantiating a class template, all its declarations (not the definitions) of its member functions are instantiated too. The class template is instantiated precisely when the full definition of a specialization is required. That is the case when it is used as a base class for example, as in your case.

So what happens is that A<B> is instantiated at

class B : public A<B>

at which point B is not a complete type yet (it is after the closing brace of the class definition). However, A<B>::action's declaration requires B to be complete, because it is crawling in the scope of it:

Subclass::mytype

What you need to do is delaying the instantiation to some point at which B is complete. One way of doing this is to modify the declaration of action to make it a member template.

template<typename T>
void action(T var) {
    (static_cast<Subclass*>(this))->do_action(var);
}

It is still type-safe because if var is not of the right type, passing var to do_action will fail.

AngularJS. How to call controller function from outside of controller component

Here is a way to call controller's function from outside of it:

angular.element(document.getElementById('yourControllerElementID')).scope().get();

where get() is a function from your controller.

You can switch

document.getElementById('yourControllerElementID')` 

to

$('#yourControllerElementID')

If you are using jQuery.

Also, if your function means changing anything on your View, you should call

angular.element(document.getElementById('yourControllerElementID')).scope().$apply();

to apply the changes.

One more thing, you should note is that scopes are initialized after the page is loaded, so calling methods from outside of scope should always be done after the page is loaded. Else you will not get to the scope at all.

UPDATE:

With the latest versions of angular, you should use

angular.element(document.getElementById('yourControllerElementID')).injector().??get('$rootScope')

And yes, this is, in fact, a bad practice, but sometimes you just need things done quick and dirty.

Forms authentication timeout vs sessionState timeout

      <sessionState timeout="2" />
      <authentication mode="Forms">
          <forms name="userLogin" path="/" timeout="60" loginUrl="Login.aspx" slidingExpiration="true"/>
      </authentication>

This configuration sends me to the login page every two minutes, which seems to controvert the earlier answers

Plotting two variables as lines using ggplot2 on the same graph

I am also new to R but trying to understand how ggplot works I think I get another way to do it. I just share probably not as a complete perfect solution but to add some different points of view.

I know ggplot is made to work with dataframes better but maybe it can be also sometimes useful to know that you can directly plot two vectors without using a dataframe.

Loading data. Original date vector length is 100 while var0 and var1 have length 50 so I only plot the available data (first 50 dates).

var0 <- 100 + c(0, cumsum(runif(49, -20, 20)))
var1 <- 150 + c(0, cumsum(runif(49, -10, 10)))
date <- seq(as.Date("2002-01-01"), by="1 month", length.out=50)    

Plotting

ggplot() + geom_line(aes(x=date,y=var0),color='red') + 
           geom_line(aes(x=date,y=var1),color='blue') + 
           ylab('Values')+xlab('date')

enter image description here

However I was not able to add a correct legend using this format. Does anyone know how?

How do I position a div at the bottom center of the screen

If you aren't comfortable with using negative margins, check this out.

div {
  position: fixed;
  left: 50%;
  bottom: 20px;
  transform: translate(-50%, -50%);
  margin: 0 auto;
}
<div>
  Your Text
</div>

Especially useful when you don't know the width of the div.


align="center" has no effect.

Since you have position:absolute, I would recommend positioning it 50% from the left and then subtracting half of its width from its left margin.

#manipulate {
    position:absolute;
    width:300px;
    height:300px;
    background:#063;
    bottom:0px;
    right:25%;
    left:50%;
    margin-left:-150px;
}

ionic build Android | error: No installed build tools found. Please install the Android build tools

This issue also occur if you do an upgrade to you cordova installation.

Check if your log error has something like:

Checking Java JDK and Android SDK versions
ANDROID_SDK_ROOT=undefined (recommended setting) <-------------
ANDROID_HOME=/{path}/android-sdk-linux (DEPRECATED)
Using Android SDK: /usr/lib/android-sdk
Starting a Gradle Daemon (subsequent builds will be faster)

In such case, just change ANDROID_HOME to ANDROID_SDK_ROOT in your ~/.bashrc or similar config file.

Where before was:

export ANDROID_HOME="/{path}/android-sdk-linux"

Now is:

export ANDROID_SDK_ROOT="/{path}/android-sdk-linux"

Don't forget source it: $ . ~/.bashrc after edition.

How to get current value of RxJS Subject or Observable?

A subscription can be created and after taking the first emitted item destroyed. Pipe is a function that uses an Observable as its input and returns another Observable as output, while not modifying the first observable. Angular 8.1.0. Packages: "rxjs": "6.5.3", "rxjs-observable": "0.0.7"

  ngOnInit() {

    ...

    // If loading with previously saved value
    if (this.controlValue) {

      // Take says once you have 1, then close the subscription
      this.selectList.pipe(take(1)).subscribe(x => {
        let opt = x.find(y => y.value === this.controlValue);
        this.updateValue(opt);
      });

    }
  }

React passing parameter via onclick event using ES6 syntax

onClick={this.handleRemove.bind(this, id)}

How to add meta tag in JavaScript

You can add it:

var meta = document.createElement('meta');
meta.httpEquiv = "X-UA-Compatible";
meta.content = "IE=edge";
document.getElementsByTagName('head')[0].appendChild(meta);

...but I wouldn't be surprised if by the time that ran, the browser had already made its decisions about how to render the page.

The real answer here has to be to output the correct tag from the server in the first place. (Sadly, you can't just not have the tag if you need to support IE. :-| )

Unable instantiate android.gms.maps.MapFragment

First Step http://developer.android.com/tools/projects/projects-eclipse.html#ReferencingLibraryProject Second Step http://developer.android.com/google/play-services/setup.html On that page it has a NOTE but we didn't pay attention

Note: You should be referencing a copy of the library that you copied to your source tree—you should not reference the library from the Android SDK directory.

But I think it's not a good way of documentation :)

What does set -e mean in a bash script?

This is an old question, but none of the answers here discuss the use of set -e aka set -o errexit in Debian package handling scripts. The use of this option is mandatory in these scripts, per Debian policy; the intent is apparently to avoid any possibility of an unhandled error condition.

What this means in practice is that you have to understand under what conditions the commands you run could return an error, and handle each of those errors explicitly.

Common gotchas are e.g. diff (returns an error when there is a difference) and grep (returns an error when there is no match). You can avoid the errors with explicit handling:

diff this that ||
  echo "$0: there was a difference" >&2
grep cat food ||
  echo "$0: no cat in the food" >&2

(Notice also how we take care to include the current script's name in the message, and writing diagnostic messages to standard error instead of standard output.)

If no explicit handling is really necessary or useful, explicitly do nothing:

diff this that || true
grep cat food || :

(The use of the shell's : no-op command is slightly obscure, but fairly commonly seen.)

Just to reiterate,

something || other

is shorthand for

if something; then
    : nothing
else
    other
fi

i.e. we explicitly say other should be run if and only if something fails. The longhand if (and other shell flow control statements like while, until) is also a valid way to handle an error (indeed, if it weren't, shell scripts with set -e could never contain flow control statements!)

And also, just to be explicit, in the absence of a handler like this, set -e would cause the entire script to immediately fail with an error if diff found a difference, or if grep didn't find a match.

On the other hand, some commands don't produce an error exit status when you'd want them to. Commonly problematic commands are find (exit status does not reflect whether files were actually found) and sed (exit status won't reveal whether the script received any input or actually performed any commands successfully). A simple guard in some scenarios is to pipe to a command which does scream if there is no output:

find things | grep .
sed -e 's/o/me/' stuff | grep ^

It should be noted that the exit status of a pipeline is the exit status of the last command in that pipeline. So the above commands actually completely mask the status of find and sed, and only tell you whether grep finally succeeded.

(Bash, of course, has set -o pipefail; but Debian package scripts cannot use Bash features. The policy firmly dictates the use of POSIX sh for these scripts, though this was not always the case.)

In many situations, this is something to separately watch out for when coding defensively. Sometimes you have to e.g. go through a temporary file so you can see whether the command which produced that output finished successfully, even when idiom and convenience would otherwise direct you to use a shell pipeline.

Splitting String with delimiter

def (value1, value2) = '1128-2'.split('-') should work.

Can anyone please try this in Groovy Console?

def (v, z) =  '1128-2'.split('-')

assert v == '1128'
assert z == '2'

Reading values from DataTable

For VB.Net is

        Dim con As New OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + "database path")
        Dim cmd As New OleDb.OleDbCommand
        Dim dt As New DataTable
        Dim da As New OleDb.OleDbDataAdapter
        con.Open()
        cmd.Connection = con
        cmd.CommandText = sql
        da.SelectCommand = cmd

        da.Fill(dt)

        For i As Integer = 0 To dt.Rows.Count
            someVar = dt.Rows(i)("fieldName")
        Next

Can I use a :before or :after pseudo-element on an input field?

I found this post as I was having the same issue, this was the solution that worked for me. As opposed to replacing the input's value just remove it and absolutely position a span behind it that is the same size, the span can have a :before pseudo class applied to it with the icon font of your choice.

<style type="text/css">

form {position: relative; }
.mystyle:before {content:url(smiley.gif); width: 30px; height: 30px; position: absolute; }
.mystyle {color:red; width: 30px; height: 30px; z-index: 1; position: absolute; }
</style>

<form>
<input class="mystyle" type="text" value=""><span class="mystyle"></span>
</form>

Conflict with dependency 'com.android.support:support-annotations' in project ':app'. Resolved versions for app (26.1.0) and test app (27.1.1) differ.

If changing target sdk version doesn't help then if you have any dependency with version 3.0.2 then change it to 3.0.1.

e.g change

androidTestImplementation 'com.android.support.test.espresso:espresso-contrib:3.0.2'

to

androidTestImplementation 'com.android.support.test.espresso:espresso-contrib:3.0.1'

How to detect running app using ADB command

Try:

adb shell pidof <myPackageName>

Standard output will be empty if the Application is not running. Otherwise, it will output the PID.

Using getline() with file input in C++

you should do as:

getline(name, sizeofname, '\n');
strtok(name, " ");

This will give you the "joht" in name then to get next token,

temp = strtok(NULL, " ");

temp will get "smith" in it. then you should use string concatination to append the temp at end of name. as:

strcat(name, temp);

(you may also append space first, to obtain a space in between).

Spring Boot Java Config Set Session Timeout

  • Spring Boot version 1.0: server.session.timeout=1200
  • Spring Boot version 2.0: server.servlet.session.timeout=10m
    NOTE: If a duration suffix is not specified, seconds will be used.

Convert command line arguments into an array in Bash

The importance of the double quotes is worth emphasizing. Suppose an argument contains whitespace.

Code:

#!/bin/bash
printf 'arguments:%s\n' "$@"
declare -a arrayGOOD=( "$@" )
declare -a arrayBAAD=(  $@  )

printf '\n%s:\n' arrayGOOD
declare -p arrayGOOD
arrayGOODlength=${#arrayGOOD[@]}
for (( i=1; i<${arrayGOODlength}+1; i++ ));
do
   echo "${arrayGOOD[$i-1]}"
done

printf '\n%s:\n' arrayBAAD
declare -p arrayBAAD
arrayBAADlength=${#arrayBAAD[@]}
for (( i=1; i<${arrayBAADlength}+1; i++ ));
do
   echo "${arrayBAAD[$i-1]}"
done

Output:

> ./bash-array-practice.sh 'The dog ate the "flea" -- and ' the mouse.
arguments:The dog ate the "flea" -- and 
arguments:the
arguments:mouse.

arrayGOOD:
declare -a arrayGOOD='([0]="The dog ate the \"flea\" -- and " [1]="the" [2]="mouse.")'
The dog ate the "flea" -- and 
the
mouse.

arrayBAAD:
declare -a arrayBAAD='([0]="The" [1]="dog" [2]="ate" [3]="the" [4]="\"flea\"" [5]="--" [6]="and" [7]="the" [8]="mouse.")'
The
dog
ate
the
"flea"
--
and
the
mouse.
> 

return value after a promise

Use a pattern along these lines:

function getValue(file) {
  return lookupValue(file);
}

getValue('myFile.txt').then(function(res) {
  // do whatever with res here
});

(although this is a bit redundant, I'm sure your actual code is more complicated)

Calculate percentage saved between two numbers?

If total no is: 200 and getting 50 number

then take percentage of 50 in 200 is:

(50/200)*100 = 25%

How to pass a parameter to Vue @click event handler

I had the same issue and here is how I manage to pass through:

In your case you have addToCount() which is called. now to pass down a param when user clicks, you can say @click="addToCount(item.contactID)"

in your function implementation you can receive the params like:

addToCount(paramContactID){
 // the paramContactID contains the value you passed into the function when you called it
 // you can do what you want to do with the paramContactID in here!

}

What causes the error "undefined reference to (some function)"?

It's a linker error. ld is the linker, so if you get an error message ending with "ld returned 1 exit status", that tells you that it's a linker error.

The error message tells you that none of the object files you're linking against contains a definition for avergecolumns. The reason for that is that the function you've defined is called averagecolumns (in other words: you misspelled the function name when calling the function (and presumably in the header file as well - otherwise you'd have gotten a different error at compile time)).

How do I get interactive plots again in Spyder/IPython/matplotlib?

After applying : Tools > preferences > Graphics > Backend > Automatic Just restart the kernel enter image description here

And you will surely get Interactive Plot. Happy Coding!

How to create a GUID / UUID

A typescript version of broofa's update from 2017-06-28, based on crypto API:

function genUUID() {
        // Reference: https://stackoverflow.com/a/2117523/709884
        return ("10000000-1000-4000-8000-100000000000").replace(/[018]/g, s => {
            const c = Number.parseInt(s, 10)
            return (c ^ crypto.getRandomValues(new Uint8Array(1))[0] & 15 >> c / 4).toString(16)
        })
}

Reasons:

  • Use of + between number[] and number isn't valid
  • The conversion from string to number has to be explicit

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

This one worked for me

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

Java: How to set Precision for double value?

This is an easy way to do it:

String formato = String.format("%.2f");

It sets the precision to 2 digits.

If you only want to print, use it this way:

System.out.printf("%.2f",123.234);

Eclipse error, "The selection cannot be launched, and there are no recent launches"

Follow these steps to run your application on the device connected. 1. Change directories to the root of your Android project and execute: ant debug 2. Make sure the Android SDK platform-tools/ directory is included in your PATH environment variable, then execute: adb install bin/<*your app name*>-debug.apk On your device, locate <*your app name*> and open it.

Refer Running App

Storing Images in PostgreSQL

Updating to 2012, when we see that image sizes, and number of images, are growing and growing, in all applications...

We need some distinction between "original image" and "processed image", like thumbnail.

As Jcoby's answer says, there are two options, then, I recommend:

  • use blob (Binary Large OBject): for original image store, at your table. See Ivan's answer (no problem with backing up blobs!), PostgreSQL additional supplied modules, How-tos etc.

  • use a separate database with DBlink: for original image store, at another (unified/specialized) database. In this case, I prefer bytea, but blob is near the same. Separating database is the best way for a "unified image webservice".

  • use bytea (BYTE Array): for caching thumbnail images. Cache the little images to send it fast to the web-browser (to avoiding rendering problems) and reduce server processing. Cache also essential metadata, like width and height. Database caching is the easiest way, but check your needs and server configs (ex. Apache modules): store thumbnails at file system may be better, compare performances. Remember that it is a (unified) web-service, then can be stored at a separate database (with no backups), serving many tables. See also PostgreSQL binary data types manual, tests with bytea column, etc.

NOTE1: today the use of "dual solutions" (database+filesystem) is deprecated (!). There are many advantages to using "only database" instead dual. PostgreSQL have comparable performance and good tools for export/import/input/output.

NOTE2: remember that PostgreSQL have only bytea, not have a default Oracle's BLOB: "The SQL standard defines (...) BLOB. The input format is different from bytea, but the provided functions and operators are mostly the same",Manual.


EDIT 2014: I have not changed the original text above today (my answer was Apr 22 '12, now with 14 votes), I am opening the answer for your changes (see "Wiki mode", you can edit!), for proofreading and for updates.
The question is stable (@Ivans's '08 answer with 19 votes), please, help to improve this text.

Closing Application with Exit button

Below used main.xml file

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TextView android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/txt1" android:text="txt1" />
<TextView android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/txt2"   android:text="txt2"/>
<Button android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/btn1"
    android:text="Close App" />
  </LinearLayout>

and text.java file is below


import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

public class testprj extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    Button btn1 = (Button) findViewById(R.id.btn1);
    btn1.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            finish();
            System.exit(0);
        }
    });
    }
 }

Define make variable at rule execution time

In your example, the TMP variable is set (and the temporary directory created) whenever the rules for out.tar are evaluated. In order to create the directory only when out.tar is actually fired, you need to move the directory creation down into the steps:

out.tar : 
    $(eval TMP := $(shell mktemp -d))
    @echo hi $(TMP)/hi.txt
    tar -C $(TMP) cf $@ .
    rm -rf $(TMP)

The eval function evaluates a string as if it had been typed into the makefile manually. In this case, it sets the TMP variable to the result of the shell function call.

edit (in response to comments):

To create a unique variable, you could do the following:

out.tar : 
    $(eval $@_TMP := $(shell mktemp -d))
    @echo hi $($@_TMP)/hi.txt
    tar -C $($@_TMP) cf $@ .
    rm -rf $($@_TMP)

This would prepend the name of the target (out.tar, in this case) to the variable, producing a variable with the name out.tar_TMP. Hopefully, that is enough to prevent conflicts.

Hosting a Maven repository on github

Another alternative is to use any web hosting with webdav support. You will need some space for this somewhere of course but it is straightforward to set up and a good alternative to running a full blown nexus server.

add this to your build section

     <extensions>
        <extension>
        <artifactId>wagon-webdav-jackrabbit</artifactId>
        <groupId>org.apache.maven.wagon</groupId>
        <version>2.2</version>
        </extension>
    </extensions>

Add something like this to your distributionManagement section

<repository>
    <id>release.repo</id>
    <url>dav:http://repo.jillesvangurp.com/releases/</url>
</repository>

Finally make sure to setup the repository access in your settings.xml

add this to your servers section

    <server>
        <id>release.repo</id>
        <username>xxxx</username>
        <password>xxxx</password>
    </server>

and a definition to your repositories section

            <repository>
                <id>release.repo</id>
                <url>http://repo.jillesvangurp.com/releases</url>
                <releases>
                    <enabled>true</enabled>
                </releases>
                <snapshots>
                    <enabled>false</enabled>
                </snapshots>
            </repository>

Finally, if you have any standard php hosting, you can use something like sabredav to add webdav capabilities.

Advantages: you have your own maven repository Downsides: you don't have any of the management capabilities in nexus; you need some webdav setup somewhere

How to push JSON object in to array using javascript

You need to have the 'data' array outside of the loop, otherwise it will get reset in every loop and also you can directly push the json. Find the solution below:-

var my_json;
$.getJSON("https://api.thingspeak.com/channels/"+did+"/feeds.json?api_key="+apikey+"&results=300", function(json1) {
console.log(json1);
var data = [];
json1.feeds.forEach(function(feed,i){
    console.log("\n The details of " + i + "th Object are :  \nCreated_at: " + feed.created_at + "\nEntry_id:" + feed.entry_id + "\nField1:" + feed.field1 + "\nField2:" + feed.field2+"\nField3:" + feed.field3);      
    my_json = feed;
    console.log(my_json); //Object {created_at: "2017-03-14T01:00:32Z", entry_id: 33358, field1: "4", field2: "4", field3: "0"}
    data.push(my_json);
     //["2017-03-14T01:00:32Z", 33358, "4", "4", "0"]
}); 
console.log(data);

No module named MySQLdb

pip install PyMySQL

and then add this two lines to your Project/Project/init.py

import pymysql
pymysql.install_as_MySQLdb()

Works on WIN and python 3.3+

ReferenceError: $ is not defined

It's one of the common mistake everybody make while working with jQuery, Basically $ is an alias of jQuery() so when you try to call/access it before declaring the function will endup throwing this error.

Reasons might be

1) Path to jQuery library you included is not correct.

2) Added library after the script were you see that error

To solve this

Load the jquery library beginning of all your javascript files/scripts.

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>

entity framework Unable to load the specified metadata resource

Craig Stuntz has written an extensive (in my opinion) blog post on troubleshooting this exact error message, I personally would start there.

The following res: (resource) references need to point to your model.

<add name="Entities" connectionString="metadata=
    res://*/Models.WraithNath.co.uk.csdl|
    res://*/Models.WraithNath.co.uk.ssdl|
    res://*/Models.WraithNath.co.uk.msl;

Make sure each one has the name of your .edmx file after the "*/", with the "edmx" changed to the extension for that res (.csdl, .ssdl, or .msl).

It also may help to specify the assembly rather than using "//*/".

Worst case, you can check everything (a bit slower but should always find the resource) by using

<add name="Entities" connectionString="metadata=
        res://*/;provider= <!-- ... -->

How can I let a user download multiple files when a button is clicked?

This is the easiest way I have found to download multiple files.

$('body').on('click','.download_btn',function(){
    downloadFiles([
        ['File1.pdf', 'File1-link-here'],
        ['File2.pdf', 'File2-link-here'],
        ['File3.pdf', 'File3-link-here'],
        ['File4.pdf', 'File4-link-here']
    ]);
})
function downloadFiles(files){
    if(files.length == 0){
        return;
    }
    file = files.pop();
    var Link = $('body').append('<a href="'+file[1]+'" download="file[0]"></a>');
    Link[0].click(); 
    Link.remove();
    downloadFiles(files);
}

This should be work for you. Thank You.

multiple conditions for JavaScript .includes() method

How about ['hello', 'hi', 'howdy'].includes(str)?

Python: How would you save a simple settings/config file?

Save and load a dictionary. You will have arbitrary keys, values and arbitrary number of key, values pairs.

How do I disable a href link in JavaScript?

I had a similar need, but my motivation was to prevent the link from being double-clicked. I accomplished it using jQuery:

$(document).ready(function() {
    $("#myLink").on('click', doSubmit);
});

var doSubmit = function() {
    $("#myLink").off('click');
    // do things here
};

The HTML looks like this:

<a href='javascript: void(0);' id="myLink">click here</a>

Difference between frontend, backend, and middleware in web development

Here is one breakdown:

Front-end tier -> User Interface layer usually consisting of a mix of HTML, Javascript, CSS, Flash, and various server-side code like ASP.Net, classic ASP, PHP, etc. Think of this as being closest to the user in terms of code.

Middleware, middle-tier -> One tier back, generally referred to as the "plumbing" part of a system. Java and C# are common languages for writing this part that could be viewed as the glue between the UI and the data and can be webservices or WCF components or other SOA components possibly.

Back-end tier -> Databases and other data stores are generally at this level. Oracle, MS-SQL, MySQL, SAP, and various off-the-shelf pieces of software come to mind for this piece of software that is the final processing of the data.

Overlap can exist between any of these as you could have everything poured into one layer like an ASP.Net website that uses the built-in AJAX functionality that generates Javascript while the code behind may contain database commands making the code behind contain both middle and back-end tiers. Alternatively, one could use VBScript to act as all the layers using ADO objects and merging all three tiers into one.

Similarly, taking middleware and either front or back-end can be combined in some cases.

Bottlenecks generally have a few different levels to them:

1) Database or back-end processing -> This can vary from payroll or sales or other tasks where the throughput to the database is bogging things down.

2) Middleware bottlenecks -> This would be where some web service may be hitting capacity but the front and back ends have bandwidth to handle more traffic. Alternatively, there may be some server that is part of a system that isn't quite the UI part or the raw data that can be a bottleneck using something like Biztalk or MSMQ.

3) Front-end bottlenecks -> This could client or server-side issues. For example, if you took a low-end PC and had it load a web page that consisted of a lot of data being downloaded, the client could be where the bottleneck is. Similarly, the server could be queuing up requests if it is getting hammered with requests like what Amazon.com or other high-traffic websites may get at times.

Some of this is subject to interpretation, so it isn't perfect by any means and YMMV.


EDIT: Something to consider is that some systems can have multiple front-ends or back-ends. For example, a content management system will likely have a way for site visitors to view the content that is a front-end but what about how content editors are able to change the data on the site? The ability to pull up this data could be seen as front-end since it is a UI component or it could be seen as a back-end since it is used by internal users rather than the general public viewing the site. Thus, there is something to be said for context here.

Do you need to dispose of objects and set them to null?

When an object implements IDisposable you should call Dispose (or Close, in some cases, that will call Dispose for you).

You normally do not have to set objects to null, because the GC will know that an object will not be used anymore.

There is one exception when I set objects to null. When I retrieve a lot of objects (from the database) that I need to work on, and store them in a collection (or array). When the "work" is done, I set the object to null, because the GC does not know I'm finished working with it.

Example:

using (var db = GetDatabase()) {
    // Retrieves array of keys
    var keys = db.GetRecords(mySelection); 

    for(int i = 0; i < keys.Length; i++) {
       var record = db.GetRecord(keys[i]);
       record.DoWork();
       keys[i] = null; // GC can dispose of key now
       // The record had gone out of scope automatically, 
       // and does not need any special treatment
    }
} // end using => db.Dispose is called

.htaccess deny from all

This syntax has changed with the newer Apache HTTPd server, please see upgrade to apache 2.4 doc for full details.

2.2 configuration syntax was

Order deny,allow
Deny from all

2.4 configuration now is

Require all denied

Thus, this 2.2 syntax

order deny,allow
deny from all
allow from 127.0.0.1

Would ne now written

Require local

How do I create a pause/wait function using Qt?

To use the standard sleep function add the following in your .cpp file:

#include <unistd.h>

As of Qt version 4.8, the following sleep functions are available:

void QThread::msleep(unsigned long msecs)
void QThread::sleep(unsigned long secs)
void QThread::usleep(unsigned long usecs)

To use them, simply add the following in your .cpp file:

#include <QThread>

Reference: QThread (via Qt documentation): http://doc.qt.io/qt-4.8/qthread.html

Otherwise, perform these steps...

Modify the project file as follows:

CONFIG += qtestlib

Note that in newer versions of Qt you will get the following error:

Project WARNING: CONFIG+=qtestlib is deprecated. Use QT+=testlib instead.

... so, instead modify the project file as follows:

QT += testlib

Then, in your .cpp file, be sure to add the following:

#include <QtTest>

And then use one of the sleep functions like so:

usleep(100);

How to paste text to end of every line? Sublime 2

Here's the workflow I use all the time, using the keyboard only

  1. Ctrl/Cmd + A Select All
  2. Ctrl/Cmd + Shift + L Split into Lines
  3. ' Surround every line with quotes

Note that this doesn't work if there are blank lines in the selection.

Close dialog on click (anywhere)

This post may help:

http://www.jensbits.com/2010/06/16/jquery-modal-dialog-close-on-overlay-click/

See also How to close a jQuery UI modal dialog by clicking outside the area covered by the box? for explanation of when and how to apply overlay click or live event depending on how you are using dialog on page.