Programs & Examples On #Analyzer

For questions related to a person or device that analyses (or analyzes) given data

More than one file was found with OS independent path 'META-INF/LICENSE'

If you have this problem and you have a gradle .jar dependency, like this:

implementation group: 'org.mortbay.jetty', name: 'jetty', version: '6.1.26'

Interval versions until one matches and resolves the excepetion,and apply the best answer of this thread.`

Elasticsearch : Root mapping definition has unsupported parameters index : not_analyzed

As of ES 7, mapping types have been removed. You can read more details here

If you are using Ruby On Rails this means that you may need to remove document_type from your model or concern.

As an alternative to mapping types one solution is to use an index per document type.

Before:

module Searchable
  extend ActiveSupport::Concern

  included do
    include Elasticsearch::Model
    include Elasticsearch::Model::Callbacks
    index_name [Rails.env, Rails.application.class.module_parent_name.underscore].join('_')
    document_type self.name.downcase
  end
end

After:

module Searchable
  extend ActiveSupport::Concern

  included do
    include Elasticsearch::Model
    include Elasticsearch::Model::Callbacks
    index_name [Rails.env, Rails.application.class.module_parent_name.underscore, self.name.downcase].join('_')
  end
end

"PKIX path building failed" and "unable to find valid certification path to requested target"

  1. Go to URL in your browser:
  • firefox - click on HTTPS certificate chain (the lock icon right next to URL address). Click "more info" > "security" > "show certificate" > "details" > "export..". Pickup the name and choose file type example.cer
  • chrome - click on site icon left to address in address bar, select "Certificate" -> "Details" -> "Export" and save in format "Der-encoded binary, single certificate".
  1. Now you have file with keystore and you have to add it to your JVM. Determine location of cacerts files, eg. C:\Program Files (x86)\Java\jre1.6.0_22\lib\security\cacerts.

  2. Next import the example.cer file into cacerts in command line (may need administrator command prompt):

keytool -import -alias example -keystore "C:\Program Files (x86)\Java\jre1.6.0_22\lib\security\cacerts" -file example.cer

You will be asked for password which default is changeit

Restart your JVM/PC.

source: http://magicmonster.com/kb/prg/java/ssl/pkix_path_building_failed.html

OPTION (RECOMPILE) is Always Faster; Why?

The very first actions before tunning queries is to defrag/rebuild the indexes and statistics, otherway you're wasting your time.

You must check the execution plan to see if it's stable (is the same when you change the parameters), if not, you might have to create a cover index (in this case for each table) (knowing th system you can create one that is usefull for other queries too).

as an example : create index idx01_datafeed_trans On datafeed_trans ( feedid, feedDate) INCLUDE( acctNo, tradeDate)

if the plan is stable or you can stabilize it you can execute the sentence with sp_executesql('sql sentence') to save and use a fixed execution plan.

if the plan is unstable you have to use an ad-hoc statement or EXEC('sql sentence') to evaluate and create an execution plan each time. (or a stored procedure "with recompile").

Hope it helps.

How to put Google Maps V2 on a Fragment using ViewPager

By using this code we can setup MapView anywhere, inside any ViewPager or Fragment or Activity.

In the latest update of Google for Maps, only MapView is supported for fragments. MapFragment & SupportMapFragment doesn't work. I might be wrong but this is what I saw after trying to implement MapFragment & SupportMapFragment.

Setting up the layout for showing the map in the file location_fragment.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <com.google.android.gms.maps.MapView
        android:id="@+id/mapView"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</RelativeLayout>

Now, we code the Java class for showing the map in the file MapViewFragment.java:

public class MapViewFragment extends Fragment {

    MapView mMapView;
    private GoogleMap googleMap;

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View rootView = inflater.inflate(R.layout.location_fragment, container, false);

        mMapView = (MapView) rootView.findViewById(R.id.mapView);
        mMapView.onCreate(savedInstanceState);

        mMapView.onResume(); // needed to get the map to display immediately

        try {
            MapsInitializer.initialize(getActivity().getApplicationContext());
        } catch (Exception e) {
            e.printStackTrace();
        }

        mMapView.getMapAsync(new OnMapReadyCallback() {
            @Override
            public void onMapReady(GoogleMap mMap) {
                googleMap = mMap;

                // For showing a move to my location button
                googleMap.setMyLocationEnabled(true);

                // For dropping a marker at a point on the Map
                LatLng sydney = new LatLng(-34, 151);
                googleMap.addMarker(new MarkerOptions().position(sydney).title("Marker Title").snippet("Marker Description"));

                // For zooming automatically to the location of the marker
                CameraPosition cameraPosition = new CameraPosition.Builder().target(sydney).zoom(12).build();
                googleMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
            }
        });

        return rootView;
    }

    @Override
    public void onResume() {
        super.onResume();
        mMapView.onResume();
    }

    @Override
    public void onPause() {
        super.onPause();
        mMapView.onPause();
    }

    @Override
    public void onDestroy() {
        super.onDestroy();
        mMapView.onDestroy();
    }

    @Override
    public void onLowMemory() {
        super.onLowMemory();
        mMapView.onLowMemory();
    }
}

Finally you need to get the API Key for your app by registering your app at Google Cloud Console. Register your app as Native Android App.

Android : Capturing HTTP Requests with non-rooted android device

It's 2020 now, for the latest solution, you can use Burp Suite to sniffing https traffic without rooting your Android device.

Steps:

  1. Install Burp Suite

  2. Enable Proxy

  3. Import the certification in your Android phone

  4. Change you Wifi configuration to listening to proxy

  5. Profit!

I wrote the full tutorial and screenshot on how to do it at here: https://www.yodiw.com/monitor-android-network-traffic-with-burp/

Invalid character in identifier

A little bit late but I got the same error and I realized that it was because I copied some code from a PDF. Check the difference between these two: - - The first one is from hitting the minus sign on keyboard and the second is from a latex generated PDF.

How can I view the contents of an ElasticSearch index?

You can even add the size of the terms (indexed terms). Have a look at Elastic Search: how to see the indexed data

Counting no of rows returned by a select query

The syntax error is just due to a missing alias for the subquery:

select COUNT(*) from
(
select m.Company_id
from Monitor as m
    inner join Monitor_Request as mr on mr.Company_ID=m.Company_id
    group by m.Company_id
    having COUNT(m.Monitor_id)>=5)  mySubQuery  /* Alias */

What's the best way to identify hidden characters in the result of a query in SQL Server (Query Analyzer)?

To find them, you can use this

;WITH cte AS
(
   SELECT 0 AS CharCode
   UNION ALL
   SELECT CharCode + 1 FROM cte WHERE CharCode <31
)
SELECT
   *
FROM
   mytable T
     cross join cte
WHERE
   EXISTS (SELECT *
        FROM mytable Tx
        WHERE Tx.PKCol = T.PKCol
             AND
              Tx.MyField LIKE '%' + CHAR(cte.CharCode) + '%'
         )

Replacing the EXISTS with a JOIN will allow you to REPLACE them, but you'll get multiple rows... I can't think of a way around that...

Django {% with %} tags within {% if %} {% else %} tags?

Like this:

{% if age > 18 %}
    {% with patient as p %}
    <my html here>
    {% endwith %}
{% else %}
    {% with patient.parent as p %}
    <my html here>
    {% endwith %}
{% endif %}

If the html is too big and you don't want to repeat it, then the logic would better be placed in the view. You set this variable and pass it to the template's context:

p = (age > 18 && patient) or patient.parent

and then just use {{ p }} in the template.

Ruby's File.open gives "No such file or directory - text.txt (Errno::ENOENT)" error

Ditto Casper's answer:

puts Dir.pwd

As soon as you know current working directory, specify the file path relatively to that directory.

For example, if your working directory is project root, you can open a file under it directly like this

json_file = File.read(myfile.json)

How to search for a part of a word with ElasticSearch

Searching with leading and trailing wildcards is going to be extremely slow on a large index. If you want to be able to search by word prefix, remove leading wildcard. If you really need to find a substring in a middle of a word, you would be better of using ngram tokenizer.

Maven2: Missing artifact but jars are in place

I encountered similar issue. The missing artifacts (jar files) exists in ~/.m2 directory and somehow eclipse is unable to find it.

For example: Missing artifact org.jdom:jdom:jar:1.1:compile

I looked through this directory ~/.m2/repository/org/jdom/jdom/1.1 and I noticed there is this file _maven.repositories. I opened it using text editor and saw the following entry:

#NOTE: This is an internal implementation file, its format can be changed without prior notice.
#Wed Feb 13 17:12:29 SGT 2013
jdom-1.1.jar>central=
jdom-1.1.pom>central=

I simply removed the "central" word from the file:

#NOTE: This is an internal implementation file, its format can be changed without prior notice.
#Wed Feb 13 17:12:29 SGT 2013
jdom-1.1.jar>=
jdom-1.1.pom>=

and run Maven > Update Project from eclipse and it just worked :) Note that your file may contain other keyword instead of "central".

IntelliJ inspection gives "Cannot resolve symbol" but still compiles code

I tried invalidating cache, it didnt work for me.

However, I tried removing the jdk from Platform Settings and added it back and it worked.

Here's how to do it.

Project Settings -> SDKs -> Select the SDK -> Remove (-) -> Add it back again (+)

How to extract string following a pattern with grep, regex or perl

Oops, the sed command has to precede the tidy command of course:

echo "$htmlstr" | 
sed '/type="global"/d' |
tidy -q -c -wrap 0 -numeric -asxml -utf8 --merge-divs yes --merge-spans yes 2>/dev/null |
xmlstarlet sel -N x="http://www.w3.org/1999/xhtml" -T -t -m "//x:table" -v '@name' -n

Where is the Query Analyzer in SQL Server Management Studio 2008 R2?

You can use Database Engine Tuning Advisor.

This tool is for improving the query performances by examining the way queries are processed and recommended enhancements by specific indexes.

How to use the Database Engine Tuning Advisor?

1- Copy the select statement that you need to speed up into the new query.

2- Parse (Ctrl+F5).

3- Press The Icon of the (Database Engine Tuning Advisor).

Using Server.MapPath() inside a static field in ASP.NET MVC

Try HostingEnvironment.MapPath, which is static.

See this SO question for confirmation that HostingEnvironment.MapPath returns the same value as Server.MapPath: What is the difference between Server.MapPath and HostingEnvironment.MapPath?

What HTTP traffic monitor would you recommend for Windows?

I like TcpCatcher because it is very simple to use and has a modern interface. It is provided as a jar file, you just download it and run it (no installation process). Also, it comes with a very useful "on the fly" packets modification features (debug mode).

Counting Line Numbers in Eclipse

You could use a batch file with the following script:

@echo off
SET count=1
FOR /f "tokens=*" %%G IN ('dir "%CD%\src\*.java" /b /s') DO (type "%%G") >> lines.txt
SET count=1
FOR /f "tokens=*" %%G IN ('type lines.txt') DO (set /a lines+=1)
echo Your Project has currently totaled %lines% lines of code. 
del lines.txt
PAUSE

How do I read input character-by-character in Java?

Use Reader.read(). A return value of -1 means end of stream; else, cast to char.

This code reads character data from a list of file arguments:

public class CharacterHandler {
    //Java 7 source level
    public static void main(String[] args) throws IOException {
        // replace this with a known encoding if possible
        Charset encoding = Charset.defaultCharset();
        for (String filename : args) {
            File file = new File(filename);
            handleFile(file, encoding);
        }
    }

    private static void handleFile(File file, Charset encoding)
            throws IOException {
        try (InputStream in = new FileInputStream(file);
             Reader reader = new InputStreamReader(in, encoding);
             // buffer for efficiency
             Reader buffer = new BufferedReader(reader)) {
            handleCharacters(buffer);
        }
    }

    private static void handleCharacters(Reader reader)
            throws IOException {
        int r;
        while ((r = reader.read()) != -1) {
            char ch = (char) r;
            System.out.println("Do something with " + ch);
        }
    }
}

The bad thing about the above code is that it uses the system's default character set. Wherever possible, prefer a known encoding (ideally, a Unicode encoding if you have a choice). See the Charset class for more. (If you feel masochistic, you can read this guide to character encoding.)

(One thing you might want to look out for are supplementary Unicode characters - those that require two char values to store. See the Character class for more details; this is an edge case that probably won't apply to homework.)

Are 2 dimensional Lists possible in c#?

Well you certainly can use a List<List<string>> where you'd then write:

List<string> track = new List<string>();
track.Add("2349");
track.Add("The Prime Time of Your Life");
// etc
matrix.Add(track);

But why would you do that instead of building your own class to represent a track, with Track ID, Name, Artist, Album, Play Count and Skip Count properties? Then just have a List<Track>.

A free tool to check C/C++ source code against a set of coding standards?

Not exactly what you ask for, but I've found it easier to just all agree on a coding standard astyle can generate and then automate the process.

Better way to sum a property value in an array

Here's a solution I find more flexible:

function sumOfArrayWithParameter (array, parameter) {
  let sum = null;
  if (array && array.length > 0 && typeof parameter === 'string') {
    sum = 0;
    for (let e of array) if (e && e.hasOwnProperty(parameter)) sum += e[parameter];
  }
  return sum;
}

To get the sum, simply use it like that:

let sum = sumOfArrayWithParameter(someArray, 'someProperty');

Visual Studio Code - Target of URI doesn't exist 'package:flutter/material.dart'

Add dependencies. for example:- import 'package:audioplayers/audio_cache.dart'; in the above package if we only use this package then it shows error but if we add dependencies in pubspec.yaml such as

dependencies:
    flutter:
      sdk: flutter
    cupertino_icons: ^0.1.2
    audioplayers: ^0.14.1

enter image description here

then click on packages get.

as you see this, I can also insert dependencies so if you insert dependencies along with your package then you are good to go.

How do I add one month to current date in Java?

If you need a one-liner (i.e. for Jasper Reports formula) and don't mind if the adjustment is not exactly one month (i.e "30 days" is enough):

new Date($F{invoicedate}.getTime() + 30L * 24L * 60L * 60L * 1000L)

Elevating process privilege programmatically?

You can indicate the new process should be started with elevated permissions by setting the Verb property of your startInfo object to 'runas', as follows:

startInfo.Verb = "runas";

This will cause Windows to behave as if the process has been started from Explorer with the "Run as Administrator" menu command.

This does mean the UAC prompt will come up and will need to be acknowledged by the user: if this is undesirable (for example because it would happen in the middle of a lengthy process), you'll need to run your entire host process with elevated permissions by Create and Embed an Application Manifest (UAC) to require the 'highestAvailable' execution level: this will cause the UAC prompt to appear as soon as your app is started, and cause all child processes to run with elevated permissions without additional prompting.

Edit: I see you just edited your question to state that "runas" didn't work for you. That's really strange, as it should (and does for me in several production apps). Requiring the parent process to run with elevated rights by embedding the manifest should definitely work, though.

How to limit the maximum files chosen when using multiple file input

You could run some jQuery client-side validation to check:

$(function(){
    $("input[type='submit']").click(function(){
        var $fileUpload = $("input[type='file']");
        if (parseInt($fileUpload.get(0).files.length)>2){
         alert("You can only upload a maximum of 2 files");
        }
    });    
});?

http://jsfiddle.net/Curt/u4NuH/

But remember to check on the server side too as client-side validation can be bypassed quite easily.

validation of input text field in html using javascript

<pre><form name="myform" action="saveNew" method="post" enctype="multipart/form-data">
    <input type="text"   id="name"   name="name" /> 
<input type="submit"/>
</form></pre>

<script language="JavaScript" type="text/javascript">
 var frmvalidator  = new Validator("myform");
    frmvalidator.EnableFocusOnError(false); 
    frmvalidator.EnableMsgsTogether(); 
    frmvalidator.addValidation("name","req","Plese Enter Name"); 

</script>




before using above code you have to add the gen_validatorv31.js js file

Can I use git diff on untracked files?

usually when i work with remote location teams it is important for me that i have prior knowledge what change done by other teams in same file, before i follow git stages untrack-->staged-->commit for that i wrote an bash script which help me to avoid unnecessary resolve merge conflict with remote team or make new local branch and compare and merge on main branch

#set -x 
branchname=`git branch | grep -F '*' |  awk '{print $2}'`
echo $branchname
git fetch origin ${branchname}
for file in `git status | grep "modified" | awk "{print $2}" `
do
echo "PLEASE CHECK OUT GIT DIFF FOR "$file 
git difftool FETCH_HEAD $file ;
done

in above script i fetch remote main branch (not necessary its master branch)to FETCH_HEAD them make a list of my modified file only and compare modified files to git difftool

here many difftool supported by git, i configure 'Meld Diff Viewer' for good GUI comparison .

JSON forEach get Key and Value

Use forEach in combo with Object.entries().

_x000D_
_x000D_
const WALLPAPERS = [{
  WALLPAPER_KEY: 'wallpaper.image',
  WALLPAPER_VALID_KEY: 'wallpaper.image.valid',
}, {
  WALLPAPER_KEY: 'lockscreen.image',
  WALLPAPER_VALID_KEY: 'lockscreen.image.valid',
}];

WALLPAPERS.forEach((obj) => {
  for (const [key, value] of Object.entries(obj)) {
    console.log(`${key} - ${value}`);
  }
});
_x000D_
_x000D_
_x000D_

AngularJS: Can't I set a variable value on ng-click?

While @tymeJV gave a correct answer, the way to do this to be inline with angular would be:

ng-click="hidePrefs()"

and then in your controller:

$scope.hidePrefs = function() {  
  $scope.prefs = false;
}

Sql error on update : The UPDATE statement conflicted with the FOREIGN KEY constraint

If column dbo.patient_address.id_no allows NULLs then you could use this solution:

SET XACT_ABORT ON;
BEGIN TRANSACTION;

-- I assmume that [id] is the primary key of patient_address table (single column key)
-- replace the name of [id] column with the name of PK column from patient_address table
-- replace INT data type with the proper type
DECLARE @RowsForUpdate TABLE([id] INT PRIMARY KEY); 
UPDATE patient_address 
SET id_no = NULL
OUTPUT deleted.[id] INTO @RowsForUpdate ([id])
WHERE id_no='8008255601088'

UPDATE patient 
SET id_no='7008255601088' 
WHERE id_no='8008255601088'

UPDATE patient_address 
SET id_no='7008255601088' 
WHERE [id] IN (SELECT u.[id] FROM @RowsForUpdate u)

COMMIT;

How to convert int to string on Arduino?

This simply work for me:

int bpm = 60;
char text[256];
sprintf(text, "Pulso: %d     ", bpm);
//now use text as string

How to disable and then enable onclick event on <div> with javascript

I'm confused by your question, seems to me that the question title and body are asking different things. If you want to disable/enable a click event on a div simply do:

$("#id").on('click', function(){ //enables click event
    //do your thing here
});

$("#id").off('click'); //disables click event

If you want to disable a div, use the following code:

$("#id").attr('disabled','disabled');

Hope this helps.

edit: oops, didn't see the other bind/unbind answer. Sorry. Those methods are also correct, though they've been deprecated in jQuery 1.7, and replaced by on()/off()

Java: Calculating the angle between two points in degrees

I started with johncarls solution, but needed to adjust it to get exactly what I needed. Mainly, I needed it to rotate clockwise when the angle increased. I also needed 0 degrees to point NORTH. His solution got me close, but I decided to post my solution as well in case it helps anyone else.

I've added some additional comments to help explain my understanding of the function in case you need to make simple modifications.

/**
 * Calculates the angle from centerPt to targetPt in degrees.
 * The return should range from [0,360), rotating CLOCKWISE, 
 * 0 and 360 degrees represents NORTH,
 * 90 degrees represents EAST, etc...
 *
 * Assumes all points are in the same coordinate space.  If they are not, 
 * you will need to call SwingUtilities.convertPointToScreen or equivalent 
 * on all arguments before passing them  to this function.
 *
 * @param centerPt   Point we are rotating around.
 * @param targetPt   Point we want to calcuate the angle to.  
 * @return angle in degrees.  This is the angle from centerPt to targetPt.
 */
public static double calcRotationAngleInDegrees(Point centerPt, Point targetPt)
{
    // calculate the angle theta from the deltaY and deltaX values
    // (atan2 returns radians values from [-PI,PI])
    // 0 currently points EAST.  
    // NOTE: By preserving Y and X param order to atan2,  we are expecting 
    // a CLOCKWISE angle direction.  
    double theta = Math.atan2(targetPt.y - centerPt.y, targetPt.x - centerPt.x);

    // rotate the theta angle clockwise by 90 degrees 
    // (this makes 0 point NORTH)
    // NOTE: adding to an angle rotates it clockwise.  
    // subtracting would rotate it counter-clockwise
    theta += Math.PI/2.0;

    // convert from radians to degrees
    // this will give you an angle from [0->270],[-180,0]
    double angle = Math.toDegrees(theta);

    // convert to positive range [0-360)
    // since we want to prevent negative angles, adjust them now.
    // we can assume that atan2 will not return a negative value
    // greater than one partial rotation
    if (angle < 0) {
        angle += 360;
    }

    return angle;
}

Cannot construct instance of - Jackson

Your @JsonSubTypes declaration does not make sense: it needs to list implementation (sub-) classes, NOT the class itself (which would be pointless). So you need to modify that entry to list sub-class(es) there are; or use some other mechanism to register sub-classes (SimpleModule has something like addAbstractTypeMapping).

How to open the default webbrowser using java

I recast Brajesh Kumar's answer above into Clojure as follows:

(defn open-browser 
  "Open a new browser (window or tab) viewing the document at this `uri`."
  [uri]
  (if (java.awt.Desktop/isDesktopSupported)
    (let [desktop (java.awt.Desktop/getDesktop)]
      (.browse desktop (java.net.URI. uri)))
    (let [rt (java.lang.Runtime/getRuntime)]
      (.exec rt (str "xdg-open " uri)))))

in case it's useful to anyone.

Only on Firefox "Loading failed for the <script> with source"

I just had the same issue on an application that is loading a script with a relative path.

It appeared the script was simply blocked by Adblock Plus.

Try to disable your ad/script blocker (Adblock, uBlock Origin, Privacy Badger…) or relocate the script such that it does not match your ad blocker's rules.

If you don't have such a plugin installed, try to reproduce the issue while running Firefox in safe mode.

  • If you cannot reproduce it in safe mode, it means your issue is linked to one of your plugins or settings.
  • Otherwise, it might be a different issue. Make sure you have the same error message as in the question. Also look at the network tab of the developer tools to check if your script is listed (reload the page first if needed).

AngularJs ReferenceError: angular is not defined

I ran into this because I made a copy-and-paste of ngBoilerplate into my project on a Mac without Finder showing hidden files. So .bower was not copied with the rest of ngBoilerplate. Thus bower moved resources to bower_components (defult) instead of vendor (as configured) and my app didn't get angular. Probably a corner case, but it might help someone here.

Can't find System.Windows.Media namespace?

Add PresentationCore.dll to your references. This dll url in my pc - C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETFramework\v4.5\PresentationCore.dll

Best way to store chat messages in a database?

If you can avoid the need for concurrent writes to a single file, it sounds like you do not need a database to store the chat messages.

Just append the conversation to a text file (1 file per user\conversation). and have a directory/ file structure

Here's a simplified view of the file structure:

chat-1-bob.txt
        201101011029, hi
        201101011030, fine thanks.

chat-1-jen.txt
        201101011030, how are you?
        201101011035, have you spoken to bill recently?

chat-2-bob.txt
        201101021200, hi
        201101021222, about 12:22
chat-2-bill.txt
        201101021201, Hey Bob,
        201101021203, what time do you call this?

You would then only need to store the userid, conversation id (guid ?) & a reference to the file name.

I think you will find it hard to get a more simple scaleable solution.

You can use LOAD_FILE to get the data too see: http://dev.mysql.com/doc/refman/5.0/en/string-functions.html

If you have a requirement to rebuild a conversation you will need to put a value (date time) alongside your sent chat message (in the file) to allow you to merge & sort the files, but at this point it is probably a good idea to consider using a database.

Can we update primary key values of a table?

You can, under certain circumstances.

But the fact that you consider this is a strong sign that there is something wrong with your architecture: Primary keys should be pure technical and carry no business meaning whatsoever. So there should never be the need to change them.

Thomas

Find the number of downloads for a particular app in apple appstore

There is no way to know unless the particular company reveals the info. The best you can do is find a few companies that are sharing and then extrapolate based on app ranking (which is available publicly). The best you'll get is a ball park estimate.

JSON to string variable dump

You can use console.log() in Firebug or Chrome to get a good object view here, like this:

$.getJSON('my.json', function(data) {
  console.log(data);
});

If you just want to view the string, look at the Resource view in Chrome or the Net view in Firebug to see the actual string response from the server (no need to convert it...you received it this way).

If you want to take that string and break it down for easy viewing, there's an excellent tool here: http://json.parser.online.fr/

Get age from Birthdate

function getAge(birthday) {
    var today = new Date();
    var thisYear = 0;
    if (today.getMonth() < birthday.getMonth()) {
        thisYear = 1;
    } else if ((today.getMonth() == birthday.getMonth()) && today.getDate() < birthday.getDate()) {
        thisYear = 1;
    }
    var age = today.getFullYear() - birthday.getFullYear() - thisYear;
    return age;
}

JSFiddle

Using the passwd command from within a shell script

The only solution works on Ubuntu 12.04:

echo -e "new_password\nnew_password" | (passwd user)

But the second option only works when I change from:

echo "password:name" | chpasswd

To:

echo "user:password" | chpasswd

See explanations in original post: Changing password via a script

Compare two Lists for differences

This solution produces a result list, that contains all differences from both input lists. You can compare your objects by any property, in my example it is ID. The only restriction is that the lists should be of the same type:

var DifferencesList = ListA.Where(x => !ListB.Any(x1 => x1.id == x.id))
            .Union(ListB.Where(x => !ListA.Any(x1 => x1.id == x.id)));

How to Sort Multi-dimensional Array by Value?

If anyone need sort according to key best is to use below

usort($array, build_sorter('order'));

function build_sorter($key) {
   return function ($a, $b) use ($key) {
      return strnatcmp($a[$key], $b[$key]);
   };
}

Is a new line = \n OR \r\n?

\n is used for Unix systems (including Linux, and OSX).

\r\n is mainly used on Windows.

\r is used on really old Macs.

PHP_EOL constant is used instead of these characters for portability between platforms.

How can I reload .emacs after changing it?

I'm currently on Ubuntu 15.04; I like to define a key for this.
[M-insert] translates to alt-insert on my keyboard.
Put this in your .emacs file:

(global-set-key [M-insert] '(lambda() (interactive) (load-file "~/.emacs")))

How to install PyQt5 on Windows?

If you're using Windows 10, if you use

    py -m pip install pyqt5

in the command prompt it should download fine. Depending on either the version of Python or Windows sometimes python -m pip install pyqt5 isn't accepted, so you have to use py instead. pip is a good way to download a lot of stuff, so I'd recommend that.

Finishing current activity from a fragment

Every time I use finish to close the fragment, the entire activity closes. According to the docs, fragments should remain as long as the parent activity remains.

Instead, I found that I can change views back the the parent activity by using this statement: setContentView(R.layout.activity_main);

This returns me back to the parent activity.

I hope that this helps someone else who may be looking for this.

Is there a git-merge --dry-run option?

I know this is theoretically off-topic, but practically very on-topic for people landing here from a Google search.

When in doubt, you can always use the Github interface to create a pull-request and check if it indicates a clean merge is possible.

Append lines to a file using a StreamWriter

You can use like this

 using (System.IO.StreamWriter file =new System.IO.StreamWriter(FilePath,true))
             {
                    
                    
            `file.Write("SOme Text TO Write" + Environment.NewLine);         
                    
             }
        

How to change the status bar background color and text color on iOS 7?

for the background you can easily add a view, like in example:

UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0,320, 20)];
view.backgroundColor = [UIColor colorWithRed:0/255.0 green:0/255.0 blue:0/255.0 alpha:0.1];
[navbar addSubview:view];

where "navbar" is a UINavigationBar.

T-SQL and the WHERE LIKE %Parameter% clause

It should be:

...
WHERE LastName LIKE '%' + @LastName + '%';

Instead of:

...
WHERE LastName LIKE '%@LastName%'

TypeScript or JavaScript type casting

You can cast like this:

return this.createMarkerStyle(<MarkerSymbolInfo> symbolInfo);

Or like this if you want to be compatible with tsx mode:

return this.createMarkerStyle(symbolInfo as MarkerSymbolInfo);

Just remember that this is a compile-time cast, and not a runtime cast.

Increment a Integer's int value?

Integer objects are immutable, so you cannot modify the value once they have been created. You will need to create a new Integer and replace the existing one.

playerID = new Integer(playerID.intValue() + 1);

How to maintain aspect ratio using HTML IMG tag

Don't set height AND width. Use one or the other and the correct aspect ratio will be maintained.

_x000D_
_x000D_
.widthSet {_x000D_
    max-width: 64px;_x000D_
}_x000D_
_x000D_
.heightSet {_x000D_
    max-height: 64px;_x000D_
}
_x000D_
<img src="http://placehold.it/200x250" />_x000D_
_x000D_
<img src="http://placehold.it/200x250" width="64" />_x000D_
_x000D_
<img src="http://placehold.it/200x250" height="64" />_x000D_
_x000D_
<img src="http://placehold.it/200x250" class="widthSet" />_x000D_
_x000D_
<img src="http://placehold.it/200x250" class="heightSet" />
_x000D_
_x000D_
_x000D_

How to list all AWS S3 objects in a bucket using Java

It might be a workaround but this solved my problem:

ObjectListing listing = s3.listObjects( bucketName, prefix );
List<S3ObjectSummary> summaries = listing.getObjectSummaries();

while (listing.isTruncated()) {
   listing = s3.listNextBatchOfObjects (listing);
   summaries.addAll (listing.getObjectSummaries());
}

UnicodeEncodeError: 'ascii' codec can't encode character u'\xef' in position 0: ordinal not in range(128)

The problem according to your traceback is the print statement on line 136 of parseXML.py. Unfortunately you didn't see fit to post that part of your code, but I'm going to guess it is just there for debugging. If you change it to:

print repr(ch)

then you should at least see what you are trying to print.

Setting up PostgreSQL ODBC on Windows

First you download ODBC driver psqlodbc_09_01_0200-x64.zip then you installed it.After that go to START->Program->Administrative tools then you select Data Source ODBC then you double click on the same after that you select PostgreSQL 30 then you select configure then you provide proper details such as db name user Id host name password of the same database in this way you will configured your DSN connection.After That you will check SSL should be allow .

Then you go on next tab system DSN then you select ADD tabthen select postgreSQL_ANSI_64X ODBC after you that you have created PostgreSQL ODBC connection.

Way to get number of digits in an int?

With design (based on problem). This is an alternate of divide-and-conquer. We'll first define an enum (considering it's only for an unsigned int).

public enum IntegerLength {
    One((byte)1,10),
    Two((byte)2,100),
    Three((byte)3,1000),
    Four((byte)4,10000),
    Five((byte)5,100000),
    Six((byte)6,1000000),
    Seven((byte)7,10000000),
    Eight((byte)8,100000000),
    Nine((byte)9,1000000000);

    byte length;
    int value;

    IntegerLength(byte len,int value) {
        this.length = len;
        this.value = value;
    }

    public byte getLenght() {
        return length;
    }

    public int getValue() {
        return value;
    }
}

Now we'll define a class that goes through the values of the enum and compare and return the appropriate length.

public class IntegerLenght {
    public static byte calculateIntLenght(int num) {    
        for(IntegerLength v : IntegerLength.values()) {
            if(num < v.getValue()){
                return v.getLenght();
            }
        }
        return 0;
    }
}

The run time of this solution is the same as the divide-and-conquer approach.

Amazon S3 - HTTPS/SSL - Is it possible?

As previously stated, it's not directly possible, but you can set up Apache or nginx + SSL on a EC2 instance, CNAME your desired domain to that, and reverse-proxy to the (non-custom domain) S3 URLs.

How to get file URL using Storage facade in laravel 5?

Store method:

public function upload($img){
   $filename = Carbon::now() . '-' .  $img->getClientOriginalName();
   return Storage::put($filename, File::get($img)) ? $filename : '';
}

Route:

 Route::get('image/{filename}', [
        'as'   => 'product.image',
        'uses' => 'ProductController@getImage',
    ]);

Controller:

 public function getImage($filename)
    {
        $file = Storage::get($filename);

        return new Response($file, 200);
    }

View:

 <img src="{{ route('product.image', ['filename' => $yourImageName]) }}" alt="your image"/>

convert base64 to image in javascript/jquery

You can just create an Image object and put the base64 as its src, including the data:image... part like this:

var image = new Image();
image.src = 'data:image/png;base64,iVBORw0K...';
document.body.appendChild(image);

It's what they call "Data URIs" and here's the compatibility table for inner peace.

get next sequence value from database using hibernate

Here is the way I do it:

@Entity
public class ServerInstanceSeq
{
    @Id //mysql bigint(20)
    @SequenceGenerator(name="ServerInstanceIdSeqName", sequenceName="ServerInstanceIdSeq", allocationSize=20)
    @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="ServerInstanceIdSeqName")
    public Long id;

}

ServerInstanceSeq sis = new ServerInstanceSeq();
session.beginTransaction();
session.save(sis);
session.getTransaction().commit();
System.out.println("sis.id after save: "+sis.id);

Centering text in a table in Twitter Bootstrap

If it's just once, you shouldn't alter your style sheet. Just edit that particular td:

<td style="text-align: center;">

Cheers

SQL Server - Convert varchar to another collation (code page) to fix character encoding

We may need more information. Here is what I did to reproduce on SQL Server 2008:

CREATE DATABASE [Test] ON  PRIMARY 
    ( 
    NAME = N'Test'
    , FILENAME = N'...Test.mdf' 
    , SIZE = 3072KB 
    , FILEGROWTH = 1024KB 
    )
    LOG ON 
    ( 
    NAME = N'Test_log'
    , FILENAME = N'...Test_log.ldf' 
    , SIZE = 1024KB 
    , FILEGROWTH = 10%
    )
    COLLATE SQL_Latin1_General_CP850_BIN2
GO
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
SET ANSI_PADDING ON
GO
CREATE TABLE [dbo].[MyTable]
    (
    [SomeCol] [varchar](50) NULL
    ) ON [PRIMARY]
GO
Insert MyTable( SomeCol )
Select '±' Collate SQL_Latin1_General_CP1_CI_AS
GO
Select SomeCol, SomeCol Collate SQL_Latin1_General_CP1_CI_AS
From MyTable

Results show the original character. Declaring collation in the query should return the proper character from SQL Server's perspective however it may be the case that the presentation layer is then converting to something yet different like UTF-8.

How to calculate UILabel height dynamically?

CGSize maxSize = CGSizeMake(lbl.frame.size.width, CGFLOAT_MAX);
CGSize requiredSize = [lbl sizeThatFits:maxSize];
CGFloat height=requiredSize.height

Where can I view Tomcat log files in Eclipse?

Another forum provided this answer:

Ahh, figured this out. The following system properties need to be set, so that the "logging.properties" file can be picked up.

Assuming that the tomcat is located under an Eclipse project, add the following under the "Arguments" tab of its launch configuration:

-Dcatalina.base="${project_loc}\<apache-tomcat-5.5.23_loc>" 
-Dcatalina.home="${project_loc}\<apache-tomcat-5.5.23_loc>" 
-Djava.util.logging.config.file="${project_loc}\<apache-tomcat-5.5.23_loc>\conf\logging.properties" 
-Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager 

http://www.coderanch.com/t/442412/Tomcat/Tweaking-tomcat-logging-properties-file

How can I display my windows user name in excel spread sheet using macros?

Range("A1").value = Environ("Username")

This is better than Application.Username, which doesn't always supply the Windows username. Thanks to Kyle for pointing this out.

  • Application Username is the name of the User set in Excel > Tools > Options
  • Environ("Username") is the name you registered for Windows; see Control Panel >System

How to use a TRIM function in SQL Server

TRIM all SPACE's TAB's and ENTER's:

DECLARE @Str VARCHAR(MAX) = '      
          [         Foo    ]       
          '

DECLARE @NewStr VARCHAR(MAX) = ''
DECLARE @WhiteChars VARCHAR(4) =
      CHAR(13) + CHAR(10) -- ENTER
    + CHAR(9) -- TAB
    + ' ' -- SPACE

;WITH Split(Chr, Pos) AS (
    SELECT
          SUBSTRING(@Str, 1, 1) AS Chr
        , 1 AS Pos
    UNION ALL
    SELECT
          SUBSTRING(@Str, Pos, 1) AS Chr
        , Pos + 1 AS Pos
    FROM Split
    WHERE Pos <= LEN(@Str)
)
SELECT @NewStr = @NewStr + Chr
FROM Split
WHERE
    Pos >= (
        SELECT MIN(Pos)
        FROM Split
        WHERE CHARINDEX(Chr, @WhiteChars) = 0
    )
    AND Pos <= (
        SELECT MAX(Pos)
        FROM Split
        WHERE CHARINDEX(Chr, @WhiteChars) = 0
    )

SELECT '"' + @NewStr + '"'

As Function

CREATE FUNCTION StrTrim(@Str VARCHAR(MAX)) RETURNS VARCHAR(MAX) BEGIN
    DECLARE @NewStr VARCHAR(MAX) = NULL

    IF (@Str IS NOT NULL) BEGIN
        SET @NewStr = ''

        DECLARE @WhiteChars VARCHAR(4) =
              CHAR(13) + CHAR(10) -- ENTER
            + CHAR(9) -- TAB
            + ' ' -- SPACE

        IF (@Str LIKE ('%[' + @WhiteChars + ']%')) BEGIN

            ;WITH Split(Chr, Pos) AS (
                SELECT
                      SUBSTRING(@Str, 1, 1) AS Chr
                    , 1 AS Pos
                UNION ALL
                SELECT
                      SUBSTRING(@Str, Pos, 1) AS Chr
                    , Pos + 1 AS Pos
                FROM Split
                WHERE Pos <= LEN(@Str)
            )
            SELECT @NewStr = @NewStr + Chr
            FROM Split
            WHERE
                Pos >= (
                    SELECT MIN(Pos)
                    FROM Split
                    WHERE CHARINDEX(Chr, @WhiteChars) = 0
                )
                AND Pos <= (
                    SELECT MAX(Pos)
                    FROM Split
                    WHERE CHARINDEX(Chr, @WhiteChars) = 0
                )
        END
    END

    RETURN @NewStr
END

Example

-- Test
DECLARE @Str VARCHAR(MAX) = '      
          [         Foo    ]       
              '

SELECT 'Str', '"' + dbo.StrTrim(@Str) + '"'
UNION SELECT 'EMPTY', '"' + dbo.StrTrim('') + '"'
UNION SELECT 'EMTPY', '"' + dbo.StrTrim('      ') + '"'
UNION SELECT 'NULL', '"' + dbo.StrTrim(NULL) + '"'

Result

+-------+----------------+
| Test  | Result         |
+-------+----------------+
| EMPTY | ""             |
| EMTPY | ""             |
| NULL  | NULL           |
| Str   | "[   Foo    ]" |
+-------+----------------+

Which method performs better: .Any() vs .Count() > 0?

You can make a simple test to figure this out:

var query = //make any query here
var timeCount = new Stopwatch();
timeCount.Start();
if (query.Count > 0)
{
}
timeCount.Stop();
var testCount = timeCount.Elapsed;

var timeAny = new Stopwatch();
timeAny.Start();
if (query.Any())
{
}
timeAny.Stop();
var testAny = timeAny.Elapsed;

Check the values of testCount and testAny.

Create a file from a ByteArrayOutputStream

You can do it with using a FileOutputStream and the writeTo method.

ByteArrayOutputStream byteArrayOutputStream = getByteStreamMethod();
try(OutputStream outputStream = new FileOutputStream("thefilename")) {
    byteArrayOutputStream.writeTo(outputStream);
}

Source: "Creating a file from ByteArrayOutputStream in Java." on Code Inventions

Visual studio equivalent of java System.out

Or, if you want to see output in the Output window of Visual Studio, System.Diagnostics.Debug.WriteLine(stuff)

Send JSON data from Javascript to PHP?

    <html>
<script type="text/javascript">
var myJSONObject = {"bindings": 11};
alert(myJSONObject);

var stringJson =JSON.stringify(myJSONObject);
alert(stringJson);
</script>
</html>

font-weight is not working properly?

In my case, I was using Google's Roboto font. So I had to import it at the beginning of my page with its proper weights.

<link href = "https://fonts.googleapis.com/css?family=Roboto+Mono|Roboto+Slab|Roboto:300,400,500,700" rel = "stylesheet" />

TypeError: 'undefined' is not an object

I'm not sure how you could just check if something isn't undefined and at the same time get an error that it is undefined. What browser are you using?

You could check in the following way (extra = and making length a truthy evaluation)

if (typeof(sub.from) !== 'undefined' && sub.from.length) {

[update]

I see that you reset sub and thereby reset sub.from but fail to re check if sub.from exist:

for (var i = 0; i < sub.from.length; i++) {//<== assuming sub.from.exist
            mainid = sub.from[i]['id'];
            var sub = afcHelper_Submissions[mainid]; // <== re setting sub

My guess is that the error is not on the if statement but on the for(i... statement. In Firebug you can break automatically on an error and I guess it'll break on that line (not on the if statement).

HTML Image not displaying, while the src url works

My images were not getting displayed even after putting them in the correct folder, problem was they did not have the right permission, I changed the permission to read write execute. I used chmod 777 image.png. All worked then, images were getting displayed. :)

Algorithm to compare two images

I believe if you're willing to apply the approach to every possible orientation and to negative versions, a good start to image recognition (with good reliability) is to use eigenfaces: http://en.wikipedia.org/wiki/Eigenface

Another idea would be to transform both images into vectors of their components. A good way to do this is to create a vector that operates in x*y dimensions (x being the width of your image and y being the height), with the value for each dimension applying to the (x,y) pixel value. Then run a variant of K-Nearest Neighbours with two categories: match and no match. If it's sufficiently close to the original image it will fit in the match category, if not then it won't.

K Nearest Neighbours(KNN) can be found here, there are other good explanations of it on the web too: http://en.wikipedia.org/wiki/K-nearest_neighbor_algorithm

The benefits of KNN is that the more variants you're comparing to the original image, the more accurate the algorithm becomes. The downside is you need a catalogue of images to train the system first.

How to convert int[] to Integer[] in Java?

  1. Convert int[] to Integer[]

    public static Integer[] toConvertInteger(int[] ids) {
    
      Integer[] newArray = new Integer[ids.length];
         for (int i = 0; i < ids.length; i++) {
           newArray[i] = Integer.valueOf(ids[i]);
         }
       return newArray;
    }
    
  2. Convert Integer[] to int[]

    public static int[] toint(Integer[] WrapperArray) {
    
       int[] newArray = new int[WrapperArray.length];
          for (int i = 0; i < WrapperArray.length; i++) {
             newArray[i] = WrapperArray[i].intValue();
          }
       return newArray;
    }
    

Write-back vs Write-Through caching?

Write-Back is a more complex one and requires a complicated Cache Coherence Protocol(MOESI) but it is worth it as it makes the system fast and efficient.

The only benefit of Write-Through is that it makes the implementation extremely simple and no complicated cache coherency protocol is required.

Updating a local repository with changes from a GitHub repository

This should work for every default repo:

git pull origin master

If your default branch is different than master, you will need to specify the branch name:

git pull origin my_default_branch_name

How do I bind to list of checkbox values with AngularJS?

A simple solution:

<div ng-controller="MainCtrl">
  <label ng-repeat="(color,enabled) in colors">
      <input type="checkbox" ng-model="colors[color]" /> {{color}} 
  </label>
  <p>colors: {{colors}}</p>
</div>

<script>
  var app = angular.module('plunker', []);

  app.controller('MainCtrl', function($scope){
      $scope.colors = {Blue: true, Orange: true};
  });
</script>

http://plnkr.co/edit/U4VD61?p=preview

Plotting a fast Fourier transform in Python

I write this additional answer to explain the origins of the diffusion of the spikes when using FFT and especially discuss the scipy.fftpack tutorial with which I disagree at some point.

In this example, the recording time tmax=N*T=0.75. The signal is sin(50*2*pi*x) + 0.5*sin(80*2*pi*x). The frequency signal should contain two spikes at frequencies 50 and 80 with amplitudes 1 and 0.5. However, if the analysed signal does not have a integer number of periods diffusion can appear due to the truncation of the signal:

  • Pike 1: 50*tmax=37.5 => frequency 50 is not a multiple of 1/tmax => Presence of diffusion due to signal truncation at this frequency.
  • Pike 2: 80*tmax=60 => frequency 80 is a multiple of 1/tmax => No diffusion due to signal truncation at this frequency.

Here is a code that analyses the same signal as in the tutorial (sin(50*2*pi*x) + 0.5*sin(80*2*pi*x)), but with the slight differences:

  1. The original scipy.fftpack example.
  2. The original scipy.fftpack example with an integer number of signal periods (tmax=1.0 instead of 0.75 to avoid truncation diffusion).
  3. The original scipy.fftpack example with an integer number of signal periods and where the dates and frequencies are taken from the FFT theory.

The code:

import numpy as np
import matplotlib.pyplot as plt
import scipy.fftpack

# 1. Linspace
N = 600
# Sample spacing
tmax = 3/4
T = tmax / N # =1.0 / 800.0
x1 = np.linspace(0.0, N*T, N)
y1 = np.sin(50.0 * 2.0*np.pi*x1) + 0.5*np.sin(80.0 * 2.0*np.pi*x1)
yf1 = scipy.fftpack.fft(y1)
xf1 = np.linspace(0.0, 1.0/(2.0*T), N//2)

# 2. Integer number of periods
tmax = 1
T = tmax / N # Sample spacing
x2 = np.linspace(0.0, N*T, N)
y2 = np.sin(50.0 * 2.0*np.pi*x2) + 0.5*np.sin(80.0 * 2.0*np.pi*x2)
yf2 = scipy.fftpack.fft(y2)
xf2 = np.linspace(0.0, 1.0/(2.0*T), N//2)

# 3. Correct positioning of dates relatively to FFT theory ('arange' instead of 'linspace')
tmax = 1
T = tmax / N # Sample spacing
x3 = T * np.arange(N)
y3 = np.sin(50.0 * 2.0*np.pi*x3) + 0.5*np.sin(80.0 * 2.0*np.pi*x3)
yf3 = scipy.fftpack.fft(y3)
xf3 = 1/(N*T) * np.arange(N)[:N//2]

fig, ax = plt.subplots()
# Plotting only the left part of the spectrum to not show aliasing
ax.plot(xf1, 2.0/N * np.abs(yf1[:N//2]), label='fftpack tutorial')
ax.plot(xf2, 2.0/N * np.abs(yf2[:N//2]), label='Integer number of periods')
ax.plot(xf3, 2.0/N * np.abs(yf3[:N//2]), label='Correct positioning of dates')
plt.legend()
plt.grid()
plt.show()

Output:

As it can be here, even with using an integer number of periods some diffusion still remains. This behaviour is due to a bad positioning of dates and frequencies in the scipy.fftpack tutorial. Hence, in the theory of discrete Fourier transforms:

  • the signal should be evaluated at dates t=0,T,...,(N-1)*T where T is the sampling period and the total duration of the signal is tmax=N*T. Note that we stop at tmax-T.
  • the associated frequencies are f=0,df,...,(N-1)*df where df=1/tmax=1/(N*T) is the sampling frequency. All harmonics of the signal should be multiple of the sampling frequency to avoid diffusion.

In the example above, you can see that the use of arange instead of linspace enables to avoid additional diffusion in the frequency spectrum. Moreover, using the linspace version also leads to an offset of the spikes that are located at slightly higher frequencies than what they should be as it can be seen in the first picture where the spikes are a little bit at the right of the frequencies 50 and 80.

I'll just conclude that the example of usage should be replace by the following code (which is less misleading in my opinion):

import numpy as np
from scipy.fftpack import fft

# Number of sample points
N = 600
T = 1.0 / 800.0
x = T*np.arange(N)
y = np.sin(50.0 * 2.0*np.pi*x) + 0.5*np.sin(80.0 * 2.0*np.pi*x)
yf = fft(y)
xf = 1/(N*T)*np.arange(N//2)
import matplotlib.pyplot as plt
plt.plot(xf, 2.0/N * np.abs(yf[0:N//2]))
plt.grid()
plt.show()

Output (the second spike is not diffused anymore):

I think this answer still bring some additional explanations on how to apply correctly discrete Fourier transform. Obviously, my answer is too long and there is always additional things to say (ewerlopes talked briefly about aliasing for instance and a lot can be said about windowing), so I'll stop.

I think that it is very important to understand deeply the principles of discrete Fourier transform when applying it because we all know so much people adding factors here and there when applying it in order to obtain what they want.

Display open transactions in MySQL

By using this query you can see all open transactions.

List All:

SHOW FULL PROCESSLIST  

if you want to kill a hang transaction copy transaction id and kill transaction by using this command:

KILL <id>    // e.g KILL 16543

What does 'public static void' mean in Java?

The three words have orthogonal meanings.

public means that the method will be visible from classes in other packages.

static means that the method is not attached to a specific instance, and it has no "this". It is more or less a function.

void is the return type. It means "this method returns nothing".

Limit number of characters allowed in form input text field

Maxlength

The maximum number of characters that will be accepted as input. The maxlength attribute specifies the maximum number of characters allowed in the element.

Maxlength W3 schools

<form action="/action_page.php">
    Username: <input type="text" name="usrname" maxlength="5"><br>
    <input type="submit" value="Submit">
</form>

Make first letter of a string upper case (with maximum performance)

Check if the string is not null then convert the first character to upper case and the rest of them to lower case:

public static string FirstCharToUpper(string str)
{
    return str?.First().ToString().ToUpper() + str?.Substring(1).ToLower();
}

How can I check the system version of Android?

Build.VERSION.RELEASE;

That will give you the actual numbers of your version; aka 2.3.3 or 2.2. The problem with using Build.VERSION.SDK_INT is if you have a rooted phone or custom rom, you could have a none standard OS (aka my android is running 2.3.5) and that will return a null when using Build.VERSION.SDK_INT so Build.VERSION.RELEASE will work no matter what!

Setting an int to Infinity in C++

int is inherently finite; there's no value that satisfies your requirements.

If you're willing to change the type of b, though, you can do this with operator overrides:

class infinitytype {};

template<typename T>
bool operator>(const T &, const infinitytype &) {
  return false;
}

template<typename T>
bool operator<(const T &, const infinitytype &) {
  return true;
}

bool operator<(const infinitytype &, const infinitytype &) {
  return false;
}


bool operator>(const infinitytype &, const infinitytype &) {
  return false;
}

// add operator==, operator!=, operator>=, operator<=...

int main() {
  std::cout << ( INT_MAX < infinitytype() ); // true
}

Dynamically Changing log4j log level

You can use following code snippet

((ch.qos.logback.classic.Logger)LoggerFactory.getLogger(packageName)).setLevel(ch.qos.logback.classic.Level.toLevel(logLevel));

Get the current displaying UIViewController on the screen in AppDelegate.m

This worked for me. I have many targets that have different controllers so previous answers didn't seemed to work.

first you want this inside your AppDelegate class:

var window: UIWindow?

then, in your function

let navigationController = window?.rootViewController as? UINavigationController
if let activeController = navigationController!.visibleViewController {
    if activeController.isKindOfClass( MyViewController )  {
        println("I have found my controller!")    
   }
}

Creating a triangle with for loops

Homework question? Well you can modify your original 'right triangle' code to generate an inverted 'right triangle' with spaces So that'll be like

for(i=0; i<6; i++)
{
    for(j=6; j>=(6-i); j--)
    {
        print(" ");
    }
    for(x=0; x<=((2*i)+1); x++)
    {
        print("*");
    }
    print("\n");
}

How to check if std::map contains a key without doing insert?

Use my_map.count( key ); it can only return 0 or 1, which is essentially the Boolean result you want.

Alternately my_map.find( key ) != my_map.end() works too.

Argument Exception "Item with Same Key has already been added"

If you want "insert or replace" semantics, use this syntax:

A[key] = value;     // <-- insert or replace semantics

It's more efficient and readable than calls involving "ContainsKey()" or "Remove()" prior to "Add()".

So in your case:

rct3Features[items[0]] = items[1];

Using ng-if as a switch inside ng-repeat?

I will suggest move all templates to separate files, and don't do spagetti inside repeat

take a look here:

html:

<div ng-repeat = "data in comments">
    <div ng-include src="buildUrl(data.type)"></div>
 </div>

js:

var app = angular.module('plunker', []);
app.controller('MainCtrl', function($scope) {

  $scope.comments = [
    {"_id":"52fb84fac6b93c152d8b4569",
       "post_id":"52fb84fac6b93c152d8b4567",
       "user_id":"52df9ab5c6b93c8e2a8b4567",
       "type":"hoot"},  
    {"_id":"52fb798cc6b93c74298b4568",
       "post_id":"52fb798cc6b93c74298b4567",
       "user_id":"52df9ab5c6b93c8e2a8b4567",
       "type":"story"},        
    {"_id":"52fb7977c6b93c5c2c8b456b",
       "post_id":"52fb7977c6b93c5c2c8b456a",
       "user_id":"52df9ab5c6b93c8e2a8b4567",
       "type":"article"}
  ];

  $scope.buildUrl = function(type) {
    return type + '.html';
  }
});

http://plnkr.co/edit/HxnirSvMHNQ748M2WeRt?p=preview

How to vertically center <div> inside the parent element with CSS?

The best approach in modern browsers is to use flexbox:

#Login {
    display: flex;
    align-items: center;
}

Some browsers will need vendor prefixes. For older browsers without flexbox support (e.g. IE 9 and lower), you'll need to implement a fallback solution using one of the older methods.

Recommended Reading

Everytime I run gulp anything, I get a assertion error. - Task function must be specified

Lower your gulp version in package.json file to 3.9.1-

"gulp": "^3.9.1",

Cross Browser Flash Detection in Javascript

If you just wanted to check whether flash is enabled, this should be enough.

function testFlash() {

    var support = false;

    //IE only
    if("ActiveXObject" in window) {

        try{
            support = !!(new ActiveXObject("ShockwaveFlash.ShockwaveFlash"));
        }catch(e){
            support = false;
        }

    //W3C, better support in legacy browser
    } else {

        support = !!navigator.mimeTypes['application/x-shockwave-flash'];

    }

    return support;

}

Note: avoid checking enabledPlugin, some mobile browser has tap-to-enable flash plugin, and will trigger false negative.

Copying PostgreSQL database to another server

If you are looking to migrate between versions (eg you updated postgres and have 9.1 running on localhost:5432 and 9.3 running on localhost:5434) you can run:

pg_dumpall -p 5432 -U myuser91 | psql -U myuser94 -d postgres -p 5434

Check out the migration docs.

Set Background cell color in PHPExcel

$objPHPExcel
    ->getActiveSheet()
    ->getStyle('A1')
    ->getFill()
    ->getStartColor()
    ->getRGB();

When to use .First and when to use .FirstOrDefault with LINQ?

Others have very well described the difference between First() and FirstOrDefault(). I want to take a further step in interpreting the semantics of these methods. In my opinion FirstOrDefault is being overused a lot. In the majority of the cases when you’re filtering data you would either expect to get back a collection of elements matching the logical condition or a single unique element by its unique identifier – such as a user, book, post etc... That’s why we can even get as far as saying that FirstOrDefault() is a code smell not because there is something wrong with it but because it’s being used way too often. This blog post explores the topic in details. IMO most of the times SingleOrDefault() is a much better alternative so watch out for this mistake and make sure you use the most appropriate method that clearly represents your contract and expectations.

Calendar.getInstance(TimeZone.getTimeZone("UTC")) is not returning UTC time

It is working for me.

Get in Timestamp type:

public static Timestamp getCurrentTimestamp() {
    TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
    final Calendar cal = Calendar.getInstance();
    Date date = cal.getTime();
    Timestamp ts = new Timestamp(date.getTime());
    return ts;
}

Get in String type:

    public static String getCurrentTimestamp() {
    TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
    final Calendar cal = Calendar.getInstance();
    Date date = cal.getTime();
    Timestamp ts = new Timestamp(date.getTime());
    return ts.toString();
}

Convert IQueryable<> type object to List<T> type?

Then just Select:

var list = source.Select(s=>new { ID = s.ID, Name = s.Name }).ToList();

(edit) Actually - the names could be inferred in this case, so you could use:

var list = source.Select(s=>new { s.ID, s.Name }).ToList();

which saves a few electrons...

LINQ where clause with lambda expression having OR clauses and null values returning incomplete results

Try writting the lambda with the same conditions as the delegate. like this:

  List<AnalysisObject> analysisObjects = 
    analysisObjectRepository.FindAll().Where(
    (x => 
       (x.ID == packageId)
    || (x.Parent != null && x.Parent.ID == packageId)
    || (x.Parent != null && x.Parent.Parent != null && x.Parent.Parent.ID == packageId)
    ).ToList();

Establish a VPN connection in cmd

Is Powershell an option?

Start Powershell:

powershell

Create the VPN Connection: Add-VpnConnection

Add-VpnConnection [-Name] <string> [-ServerAddress] <string> [-TunnelType <string> {Pptp | L2tp | Sstp | Ikev2 | Automatic}] [-EncryptionLevel <string> {NoEncryption | Optional | Required | Maximum}] [-AuthenticationMethod <string[]> {Pap | Chap | MSChapv2 | Eap}] [-SplitTunneling] [-AllUserConnection] [-L2tpPsk <string>] [-RememberCredential] [-UseWinlogonCredential] [-EapConfigXmlStream <xml>] [-Force] [-PassThru] [-WhatIf] [-Confirm] 

Edit VPN connections: Set-VpnConnection

Set-VpnConnection [-Name] <string> [[-ServerAddress] <string>] [-TunnelType <string> {Pptp | L2tp | Sstp | Ikev2 | Automatic}] [-EncryptionLevel <string> {NoEncryption | Optional | Required | Maximum}] [-AuthenticationMethod <string[]> {Pap | Chap | MSChapv2 | Eap}] [-SplitTunneling <bool>] [-AllUserConnection] [-L2tpPsk <string>] [-RememberCredential <bool>] [-UseWinlogonCredential <bool>] [-EapConfigXmlStream <xml>] [-PassThru] [-Force] [-WhatIf] [-Confirm]

Lookup VPN Connections: Get-VpnConnection

Get-VpnConnection [[-Name] <string[]>] [-AllUserConnection]

Connect: rasdial [connectionName]

rasdial connectionname [username [password | \]] [/domain:domain*] [/phone:phonenumber] [/callback:callbacknumber] [/phonebook:phonebookpath] [/prefixsuffix**]

You can manage your VPN connections with the powershell commands above, and simply use the connection name to connect via rasdial.

The results of Get-VpnConnection can be a little verbose. This can be simplified with a simple Select-Object filter:

Get-VpnConnection | Select-Object -Property Name

More information can be found here:

How to tell if a <script> tag failed to load

Here is another JQuery-based solution without any timers:

<script type="text/javascript">
function loadScript(url, onsuccess, onerror) {
$.get(url)
    .done(function() {
        // File/url exists
        console.log("JS Loader: file exists, executing $.getScript "+url)
        $.getScript(url, function() {
            if (onsuccess) {
                console.log("JS Loader: Ok, loaded. Calling onsuccess() for " + url);
                onsuccess();
                console.log("JS Loader: done with onsuccess() for " + url);
            } else {
                console.log("JS Loader: Ok, loaded, no onsuccess() callback " + url)
            }
        });
    }).fail(function() {
            // File/url does not exist
            if (onerror) {
                console.error("JS Loader: probably 404 not found. Not calling $.getScript. Calling onerror() for " + url);
                onerror();
                console.error("JS Loader: done with onerror() for " + url);
            } else {
                console.error("JS Loader: probably 404 not found. Not calling $.getScript. No onerror() callback " + url);
            }
    });
}
</script>

Thanks to: https://stackoverflow.com/a/14691735/1243926

Sample usage (original sample from JQuery getScript documentation):

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>jQuery.getScript demo</title>
  <style>
  .block {
     background-color: blue;
     width: 150px;
     height: 70px;
     margin: 10px;
  }
  </style>
  <script src="http://code.jquery.com/jquery-1.9.1.js"></script>
</head>
<body>

<button id="go">&raquo; Run</button>
<div class="block"></div>

<script>


function loadScript(url, onsuccess, onerror) {
$.get(url)
    .done(function() {
        // File/url exists
        console.log("JS Loader: file exists, executing $.getScript "+url)
        $.getScript(url, function() {
            if (onsuccess) {
                console.log("JS Loader: Ok, loaded. Calling onsuccess() for " + url);
                onsuccess();
                console.log("JS Loader: done with onsuccess() for " + url);
            } else {
                console.log("JS Loader: Ok, loaded, no onsuccess() callback " + url)
            }
        });
    }).fail(function() {
            // File/url does not exist
            if (onerror) {
                console.error("JS Loader: probably 404 not found. Not calling $.getScript. Calling onerror() for " + url);
                onerror();
                console.error("JS Loader: done with onerror() for " + url);
            } else {
                console.error("JS Loader: probably 404 not found. Not calling $.getScript. No onerror() callback " + url);
            }
    });
}


loadScript("https://raw.github.com/jquery/jquery-color/master/jquery.color.js", function() {
  console.log("loaded jquery-color");
  $( "#go" ).click(function() {
    $( ".block" )
      .animate({
        backgroundColor: "rgb(255, 180, 180)"
      }, 1000 )
      .delay( 500 )
      .animate({
        backgroundColor: "olive"
      }, 1000 )
      .delay( 500 )
      .animate({
        backgroundColor: "#00f"
      }, 1000 );
  });
}, function() { console.error("Cannot load jquery-color"); });


</script>
</body>
</html>

mongodb, replicates and error: { "$err" : "not master and slaveOk=false", "code" : 13435 }

I got here searching for the same error, but from Node.js native driver. The answer for me was combination of answers by campeterson and Prabhat.

The issue is that readPreference setting defaults to primary, which then somehow leads to the confusing slaveOk error. My problem is that I just wan to read from my replica set from any node. I don't even connect to it as to replicaset. I just connect to any node to read from it.

Setting readPreference to primaryPreferred (or better to the ReadPreference.PRIMARY_PREFERRED constant) solved it for me. Just pass it as an option to MongoClient.connect() or to client.db() or to any find(), aggregate() or other function.

const { MongoClient, ReadPreference } = require('mongodb');
const client = await MongoClient.connect(MONGODB_CONNECTIONSTRING, { readPreference: ReadPreference.PRIMARY_PREFERRED });

Bash conditionals: how to "and" expressions? (if [ ! -z $VAR && -e $VAR ])

if [ ! -z "$var" ] && [ -e "$var" ]; then
      # something ...
fi

IntelliJ, can't start simple web application: Unable to ping server at localhost:1099

Setting project's SDK in IntelliJ (File > Project Structure > Project:Project SDK) worked for me

How do I "shake" an Android device within the Android emulator to bring up the dev menu to debug my React Native app

For Linux you click on the three dots "..." beside the emulator, on Virtual sensors check "Move" and then try quickly moving either x, y or z coordinates.

enter image description here

Go to beginning of line without opening new line in VI

You can use 0 or ^ to move to beginning of the line.
And can use Shift+I to move to the beginning and switch to editing mode (Insert).

How to set time delay in javascript

setTimeout(function(){


}, 500); 

Place your code inside of the { }

500 = 0.5 seconds

2200 = 2.2 seconds

etc.

document.getelementbyId will return null if element is not defined?

Yes it will return null if it's not present you can try this below in the demo. Both will return true. The first elements exists the second doesn't.

Demo

Html

<div id="xx"></div>

Javascript:

   if (document.getElementById('xx') !=null) 
     console.log('it exists!');

   if (document.getElementById('xxThisisNotAnElementOnThePage') ==null) 
     console.log('does not exist!');

HTML5: Slider with two inputs possible?

I've been looking for a lightweight, dependency free dual slider for some time (it seemed crazy to import jQuery just for this) and there don't seem to be many out there. I ended up modifying @Wildhoney's code a bit and really like it.

_x000D_
_x000D_
function getVals(){_x000D_
  // Get slider values_x000D_
  var parent = this.parentNode;_x000D_
  var slides = parent.getElementsByTagName("input");_x000D_
    var slide1 = parseFloat( slides[0].value );_x000D_
    var slide2 = parseFloat( slides[1].value );_x000D_
  // Neither slider will clip the other, so make sure we determine which is larger_x000D_
  if( slide1 > slide2 ){ var tmp = slide2; slide2 = slide1; slide1 = tmp; }_x000D_
  _x000D_
  var displayElement = parent.getElementsByClassName("rangeValues")[0];_x000D_
      displayElement.innerHTML = slide1 + " - " + slide2;_x000D_
}_x000D_
_x000D_
window.onload = function(){_x000D_
  // Initialize Sliders_x000D_
  var sliderSections = document.getElementsByClassName("range-slider");_x000D_
      for( var x = 0; x < sliderSections.length; x++ ){_x000D_
        var sliders = sliderSections[x].getElementsByTagName("input");_x000D_
        for( var y = 0; y < sliders.length; y++ ){_x000D_
          if( sliders[y].type ==="range" ){_x000D_
            sliders[y].oninput = getVals;_x000D_
            // Manually trigger event first time to display values_x000D_
            sliders[y].oninput();_x000D_
          }_x000D_
        }_x000D_
      }_x000D_
}
_x000D_
  section.range-slider {_x000D_
    position: relative;_x000D_
    width: 200px;_x000D_
    height: 35px;_x000D_
    text-align: center;_x000D_
}_x000D_
_x000D_
section.range-slider input {_x000D_
    pointer-events: none;_x000D_
    position: absolute;_x000D_
    overflow: hidden;_x000D_
    left: 0;_x000D_
    top: 15px;_x000D_
    width: 200px;_x000D_
    outline: none;_x000D_
    height: 18px;_x000D_
    margin: 0;_x000D_
    padding: 0;_x000D_
}_x000D_
_x000D_
section.range-slider input::-webkit-slider-thumb {_x000D_
    pointer-events: all;_x000D_
    position: relative;_x000D_
    z-index: 1;_x000D_
    outline: 0;_x000D_
}_x000D_
_x000D_
section.range-slider input::-moz-range-thumb {_x000D_
    pointer-events: all;_x000D_
    position: relative;_x000D_
    z-index: 10;_x000D_
    -moz-appearance: none;_x000D_
    width: 9px;_x000D_
}_x000D_
_x000D_
section.range-slider input::-moz-range-track {_x000D_
    position: relative;_x000D_
    z-index: -1;_x000D_
    background-color: rgba(0, 0, 0, 1);_x000D_
    border: 0;_x000D_
}_x000D_
section.range-slider input:last-of-type::-moz-range-track {_x000D_
    -moz-appearance: none;_x000D_
    background: none transparent;_x000D_
    border: 0;_x000D_
}_x000D_
  section.range-slider input[type=range]::-moz-focus-outer {_x000D_
  border: 0;_x000D_
}
_x000D_
<!-- This block can be reused as many times as needed -->_x000D_
<section class="range-slider">_x000D_
  <span class="rangeValues"></span>_x000D_
  <input value="5" min="0" max="15" step="0.5" type="range">_x000D_
  <input value="10" min="0" max="15" step="0.5" type="range">_x000D_
</section>
_x000D_
_x000D_
_x000D_

How do I connect to my existing Git repository using Visual Studio Code?

Another option is to use the built-in Command Palette, which will walk you right through cloning a Git repository to a new directory.

From Using Version Control in VS Code:

You can clone a Git repository with the Git: Clone command in the Command Palette (Windows/Linux: Ctrl + Shift + P, Mac: Command + Shift + P). You will be asked for the URL of the remote repository and the parent directory under which to put the local repository.

At the bottom of Visual Studio Code you'll get status updates to the cloning. Once that's complete an information message will display near the top, allowing you to open the folder that was created.

Note that Visual Studio Code uses your machine's Git installation, and requires 2.0.0 or higher.

How can I install a .ipa file to my iPhone simulator

In Xcode 6+ and iOS8+ you can do the simple steps below

  1. Paste .app file on desktop.
  2. Open terminal and paste the commands below:

    cd desktop

    xcrun simctl install booted xyz.app

  3. Open iPhone simulator and click on app and use

For versions below iOS 8, do the following simple steps.

Note: You'll want to make sure that your app is built for all architectures, the Simulator is x386 in the Build Settings and Build Active Architecture Only set to No.

  1. Path: Library->Application Support->iPhone Simulator->7.1 (or another version if you need it)->Applications
  2. Create a new folder with the name of the app
  3. Go inside the folder and place the .app file here.

Java - Create a new String instance with specified length and filled with specific character. Best solution?

Mi solution :

  pw = "1321";
    if (pw.length() < 16){
      for(int x = pw.length() ; x < 16 ; x++){
        pw  += "*";
      }
    }

The output :

1321************

Git merge master into feature branch

Based on this article, you should:

  • create new branch which is based upon new version of master

    git branch -b newmaster

  • merge your old feature branch into new one

    git checkout newmaster

  • resolve conflict on new feature branch

The first two commands can be combined to git checkout -b newmaster.

This way your history stays clear because you don't need back merges. And you don't need to be so super cautious since you don't need to do a Git rebase.

Override standard close (X) button in a Windows Form

One situation where it is quite useful to be able to handle the x-button click event is when you are using a Form that is an MDI container. The reason is that the closeing and closed events are raised first with children and lastly with the parent. So in one scenario a user clicks the x-button to close the application and the MDI parent asks for a confirmation to proceed. In case he decides to not close the application but carry on whatever he is doing the children will already have processed the closing event potentially lost information/work whatever. One solution is to intercept the WM_CLOSE message from the Windows message loop in your main application form (i.e. which closed, terminates the application) like so:

    protected override void WndProc(ref Message m)
    {
        if (m.Msg == 0x0010) // WM_CLOSE
        {
            // If we don't want to close this window 
            if (ShowConfirmation("Are you sure?") != DialogResult.Yes) return;
        }

        base.WndProc(ref m);
    }

C++11 rvalues and move semantics confusion (return statement)

First example

std::vector<int> return_vector(void)
{
    std::vector<int> tmp {1,2,3,4,5};
    return tmp;
}

std::vector<int> &&rval_ref = return_vector();

The first example returns a temporary which is caught by rval_ref. That temporary will have its life extended beyond the rval_ref definition and you can use it as if you had caught it by value. This is very similar to the following:

const std::vector<int>& rval_ref = return_vector();

except that in my rewrite you obviously can't use rval_ref in a non-const manner.

Second example

std::vector<int>&& return_vector(void)
{
    std::vector<int> tmp {1,2,3,4,5};
    return std::move(tmp);
}

std::vector<int> &&rval_ref = return_vector();

In the second example you have created a run time error. rval_ref now holds a reference to the destructed tmp inside the function. With any luck, this code would immediately crash.

Third example

std::vector<int> return_vector(void)
{
    std::vector<int> tmp {1,2,3,4,5};
    return std::move(tmp);
}

std::vector<int> &&rval_ref = return_vector();

Your third example is roughly equivalent to your first. The std::move on tmp is unnecessary and can actually be a performance pessimization as it will inhibit return value optimization.

The best way to code what you're doing is:

Best practice

std::vector<int> return_vector(void)
{
    std::vector<int> tmp {1,2,3,4,5};
    return tmp;
}

std::vector<int> rval_ref = return_vector();

I.e. just as you would in C++03. tmp is implicitly treated as an rvalue in the return statement. It will either be returned via return-value-optimization (no copy, no move), or if the compiler decides it can not perform RVO, then it will use vector's move constructor to do the return. Only if RVO is not performed, and if the returned type did not have a move constructor would the copy constructor be used for the return.

Implicit function declarations in C

C is a very low-level language, so it permits you to create almost any legal object (.o) file that you can conceive of. You should think of C as basically dressed-up assembly language.

In particular, C does not require functions to be declared before they are used. If you call a function without declaring it, the use of the function becomes it's (implicit) declaration. In a simple test I just ran, this is only a warning in the case of built-in library functions like printf (at least in GCC), but for random functions, it will compile just fine.

Of course, when you try to link, and it can't find foo, then you will get an error.

In the case of library functions like printf, some compilers contain built-in declarations for them so they can do some basic type checking, so when the implicit declaration (from the use) doesn't match the built-in declaration, you'll get a warning.

Convert a String to a byte array and then back to the original String

Use [String.getBytes()][1] to convert to bytes and use [String(byte[] data)][2] constructor to convert back to string.

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured

“Failed to configure a DataSource” error. First, we fixed the issue by defining the data source. Next, we discussed how to work around the issue without configuring the data source at all.

https://www.baeldung.com/spring-boot-failed-to-configure-data-source

How to print out a variable in makefile

You could create a vars rule in your make file, like this:

dispvar = echo $(1)=$($(1)) ; echo

.PHONY: vars
vars:
    @$(call dispvar,SOMEVAR1)
    @$(call dispvar,SOMEVAR2)

There are some more robust ways to dump all variables here: gnu make: list the values of all variables (or "macros") in a particular run.

How to update TypeScript to latest version with npm?

Open command prompt (cmd.exe/git bash)

Recommended:

npm install -g typescript@latest

or

yarn global add typescript@latest  // if you use yarn package manager

This will install the latest typescript version if not already installed, otherwise it will update the current installation to the latest version.

And then verify which version is installed:

tsc -v

enter image description here


If you have typescript already installed you could also use the following command to update to latest version, but as commentators have reported and I confirm it that the following command does not update to latest (as of now [ Feb 10 '17])!

npm update -g typescript@latest

Bootstrap: How do I identify the Bootstrap version?

In the top of the bootstrap.css you should have comments like the below:

/*!
 * Bootstrap v2.3.1
 *
 * Copyright 2012 Twitter, Inc
 * Licensed under the Apache License v2.0
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Designed and built with all the love in the world @twitter by @mdo and @fat.
 */

If they are not there, then they have probably been deleted.

VERSIONS:

You can review version history here. Backward compatibility shouldn't be broken if the source is v2.0.0 (Jan 2012) and above. If it is prior to v2.0.0 there are details on upgrading here.

Positioning background image, adding padding

this is actually pretty easily done. You're almost there, doing what you've done with background-position: right center;. What is actually needed in this case is something very much like that. Let's convert these to percentages. We know that center=50%, so that's easy enough. Now, in order to get the padding you wanted, you need to position the background like so: background-position: 99% 50%.

The second, and more effective way of going about this, is to use the same background-position idea, and just use background-position: 400px (width of parent) 50%;. Of course, this method requires a static width, but will give you the same thing every time.

Method 1 (99% 50%)
Method 2 (400px 50%)

How do I align views at the bottom of the screen?

I used the solution Janusz posted, but I added padding to the last View since the top part of my layout was a ScrollView.

The ScrollView will be partly hidden as it grows with content. Using android:paddingBottom on the last View helps show all the content in the ScrollView.

Swapping two variable value without using third variable

You may do....in easy way...within one line Logic

#include <stdio.h>

int main()
{
    int a, b;
    printf("Enter A :");
    scanf("%d",&a);
    printf("Enter B :");
    scanf("%d",&b);
    int a = 1,b = 2;
    a=a^b^(b=a);
    printf("\nValue of A=%d B=%d ",a,b);

    return 1;
}

or

#include <stdio.h>

int main()
{
    int a, b;
    printf("Enter A :");
    scanf("%d",&a);
    printf("Enter B :");
    scanf("%d",&b);
    int a = 1,b = 2;
    a=a+b-(b=a);
    printf("\nValue of A=%d B=%d ",a,b);

    return 1;
}

How can I check if two segments intersect?

Based on Liran's and Grumdrig's excellent answers here is a complete Python code to verify if closed segments do intersect. Works for collinear segments, segments parallel to axis Y, degenerate segments (devil is in details). Assumes integer coordinates. Floating point coordinates require a modification to points equality test.

def side(a,b,c):
    """ Returns a position of the point c relative to the line going through a and b
        Points a, b are expected to be different
    """
    d = (c[1]-a[1])*(b[0]-a[0]) - (b[1]-a[1])*(c[0]-a[0])
    return 1 if d > 0 else (-1 if d < 0 else 0)

def is_point_in_closed_segment(a, b, c):
    """ Returns True if c is inside closed segment, False otherwise.
        a, b, c are expected to be collinear
    """
    if a[0] < b[0]:
        return a[0] <= c[0] and c[0] <= b[0]
    if b[0] < a[0]:
        return b[0] <= c[0] and c[0] <= a[0]

    if a[1] < b[1]:
        return a[1] <= c[1] and c[1] <= b[1]
    if b[1] < a[1]:
        return b[1] <= c[1] and c[1] <= a[1]

    return a[0] == c[0] and a[1] == c[1]

#
def closed_segment_intersect(a,b,c,d):
    """ Verifies if closed segments a, b, c, d do intersect.
    """
    if a == b:
        return a == c or a == d
    if c == d:
        return c == a or c == b

    s1 = side(a,b,c)
    s2 = side(a,b,d)

    # All points are collinear
    if s1 == 0 and s2 == 0:
        return \
            is_point_in_closed_segment(a, b, c) or is_point_in_closed_segment(a, b, d) or \
            is_point_in_closed_segment(c, d, a) or is_point_in_closed_segment(c, d, b)

    # No touching and on the same side
    if s1 and s1 == s2:
        return False

    s1 = side(c,d,a)
    s2 = side(c,d,b)

    # No touching and on the same side
    if s1 and s1 == s2:
        return False

    return True

Add external libraries to CMakeList.txt c++

I would start with upgrade of CMAKE version.

You can use INCLUDE_DIRECTORIES for header location and LINK_DIRECTORIES + TARGET_LINK_LIBRARIES for libraries

INCLUDE_DIRECTORIES(your/header/dir)
LINK_DIRECTORIES(your/library/dir)
rosbuild_add_executable(kinectueye src/kinect_ueye.cpp)
TARGET_LINK_LIBRARIES(kinectueye lib1 lib2 lib2 ...)

note that lib1 is expanded to liblib1.so (on Linux), so use ln to create appropriate links in case you do not have them

Preferred way of getting the selected item of a JComboBox

Don't cast unless you must. There's nothign wrong with calling toString().

How to see JavaDoc in IntelliJ IDEA?

I have noticed that selecting the method name and pressing F2(Quick Documentation) dispalys it's JavaDoc. I am using Intellij 2016, and Eclipse Keymap

SQL how to check that two tables has exactly the same data?

Enhancement to dietbuddha's answer...

select * from
(
    select * from tableA
    minus
    select * from tableB
)
union all
select * from
(
    select * from tableB
    minus
    select * from tableA
)

Get month name from Date

It can be done as follows too:

var x = new Date().toString().split(' ')[1];    // "Jul"

How to get the nth occurrence in a string?

function getStringReminder(str, substr, occ) {
   let index = str.indexOf(substr);
   let preindex = '';
   let i = 1;
   while (index !== -1) {
      preIndex = index;
      if (occ == i) {
        break;
      }
      index = str.indexOf(substr, index + 1)
      i++;
   }
   return preIndex;
}
console.log(getStringReminder('bcdefgbcdbcd', 'bcd', 3));

In PHP, what is a closure and why does it use the "use" identifier?

This is how PHP expresses a closure. This is not evil at all and in fact it is quite powerful and useful.

Basically what this means is that you are allowing the anonymous function to "capture" local variables (in this case, $tax and a reference to $total) outside of it scope and preserve their values (or in the case of $total the reference to $total itself) as state within the anonymous function itself.

Pass multiple parameters in Html.BeginForm MVC

Another option I like, which can be generalized once I start seeing the code not conform to DRY, is to use one controller that redirects to another controller.

public ActionResult ClientIdSearch(int cid)
{
  var action = String.Format("Details/{0}", cid);

  return RedirectToAction(action, "Accounts");
}

I find this allows me to apply my logic in one location and re-use it without have to sprinkle JavaScript in the views to handle this. And, as I mentioned I can then refactor for re-use as I see this getting abused.

TypeError: Converting circular structure to JSON in nodejs

I came across this issue when not using async/await on a asynchronous function (api call). Hence adding them / using the promise handlers properly cleared the error.

Print a div using javascript in angularJS single page application

This is what worked for me in Chrome and Firefox! This will open the little print window and close it automatically once you've clicked print.

var printContents = document.getElementById('div-id-selector').innerHTML;
            var popupWin = window.open('', '_blank', 'width=800,height=800,scrollbars=no,menubar=no,toolbar=no,location=no,status=no,titlebar=no,top=50');
            popupWin.window.focus();
            popupWin.document.open();
            popupWin.document.write('<!DOCTYPE html><html><head><title>TITLE OF THE PRINT OUT</title>' 
                                    +'<link rel="stylesheet" type="text/css" href="app/directory/file.css" />' 
                                    +'</head><body onload="window.print(); window.close();"><div>' 
                                    + printContents + '</div></html>');
            popupWin.document.close();

How do I copy an object in Java?

Just follow as below:

public class Deletable implements Cloneable{

    private String str;
    public Deletable(){
    }
    public void setStr(String str){
        this.str = str;
    }
    public void display(){
        System.out.println("The String is "+str);
    }
    protected Object clone() throws CloneNotSupportedException {
        return super.clone();
    }
}

and wherever you want to get another object, simple perform cloning. e.g:

Deletable del = new Deletable();
Deletable delTemp = (Deletable ) del.clone(); // this line will return you an independent
                                 // object, the changes made to this object will
                                 // not be reflected to other object

When should use Readonly and Get only properties

A property that has only a getter is said to be readonly. Cause no setter is provided, to change the value of the property (from outside).

C# has has a keyword readonly, that can be used on fields (not properties). A field that is marked as "readonly", can only be set once during the construction of an object (in the constructor).

private string _name = "Foo"; // field for property Name;
private bool _enabled = false; // field for property Enabled;

public string Name{ // This is a readonly property.
  get {
    return _name;  
  }
}

public bool Enabled{ // This is a read- and writeable property.
  get{
    return _enabled;
  }
  set{
    _enabled = value;
  }
} 

iPhone/iPad browser simulator?

Both Chrome and Firefox now have built-in emulators. They aren't perfect but are good enough that can get you almost all of the way before testing on an actual device. The best part is if you like the browser's developer tools (Chrome, Firefox), you can use them while emulating.

To get the emulator: [Ctrl+Shift+M] and select the device that you want to emulate. You might have to refresh the page, esp if you have anything that depends on script that executes on page load.

Google Chrome Emulation mode

Internet Explorer also has a device emulation mode. F12, then CTRL+8. It's not quite as straight forward as the Chrome Mobile Device emulation, but does allow you to simulate geolocation:

Internet Explorer Emulation mode

How can I check if char* variable points to empty string?

Give it a chance:

Try getting string via function gets(string) then check condition as if(string[0] == '\0')

If hasClass then addClass to parent

You can't use $(this) since jQuery doesn't know what it is there. You seem to be overcomplicating things. You can do $('#content h1.aktiv').hide(). There's no reason to test to see if the class exists.

How can I selectively escape percent (%) in Python strings?

I have tried different methods to print a subplot title, look how they work. It's different when i use Latex.

It works with '%%' and 'string'+'%' in a typical case.

If you use Latex it worked using 'string'+'\%'

So in a typical case:

import matplotlib.pyplot as plt
fig,ax = plt.subplots(4,1)
float_number = 4.17
ax[0].set_title('Total: (%1.2f' %float_number + '\%)')
ax[1].set_title('Total: (%1.2f%%)' %float_number)
ax[2].set_title('Total: (%1.2f' %float_number + '%%)')
ax[3].set_title('Total: (%1.2f' %float_number + '%)')

Title examples with %

If we use latex:

import matplotlib.pyplot as plt
import matplotlib
font = {'family' : 'normal',
        'weight' : 'bold',
        'size'   : 12}
matplotlib.rc('font', **font)
matplotlib.rcParams['text.usetex'] = True
matplotlib.rcParams['text.latex.unicode'] = True
fig,ax = plt.subplots(4,1)
float_number = 4.17
#ax[0].set_title('Total: (%1.2f\%)' %float_number) This makes python crash
ax[1].set_title('Total: (%1.2f%%)' %float_number)
ax[2].set_title('Total: (%1.2f' %float_number + '%%)')
ax[3].set_title('Total: (%1.2f' %float_number + '\%)')

We get this: Title example with % and latex

How to check if a key exists in Json Object and get its value

Try

private boolean hasKey(JSONObject jsonObject, String key) {
    return jsonObject != null && jsonObject.has(key);
}

  try {
        JSONObject jsonObject = new JSONObject(yourJson);
        if (hasKey(jsonObject, "labelData")) {
            JSONObject labelDataJson = jsonObject.getJSONObject("LabelData");
            if (hasKey(labelDataJson, "video")) {
                String video = labelDataJson.getString("video");
            }
        }
    } catch (JSONException e) {

    }

How can I enable Assembly binding logging?

  1. Create a new Application Pool

  2. Go to the Advanced Settings of this application pool

  3. Set the Enable 32-Bit Application to True

  4. Point your web application to use this new Pool

Screenshot (IIS-ApplicationPool)

Hidden Features of Xcode

Turn off the "undo past the last point" warning

When you attempt to undo after saving, you will get the following prompt:

"You are about to undo past the last point this file was saved. Do you want to do this?"

To get rid of this warning, enter the following into a terminal window:

defaults write com.apple.Xcode XCShowUndoPastSaveWarning NO

Change the company name in template files

Paste this into the Terminal application:

defaults write com.apple.Xcode PBXCustomTemplateMacroDefinitions '{"ORGANIZATIONNAME" = "Microsoft";}'

Change "com.yourcompanyname" in all your templates:

  1. Find the directory: /Developer/Platforms/iPhoneOS.platform/Developer/Library/Xcode/Project Templates/Application
  2. Use your favourite multi-file search-and-replace tool to change com.yourcompany to whatever value you normally use to build for a device. I used BBEdit's multi-find-and-replace after I opened the whole directory. You should be replacing the value in all the info.plist files. I found 8 files to change. The number of times a build has failed because I forgot to change this string is ridiculous.

Quickly jump to a Group in the Groups and Files pane

  • Control ^ Option ? Shift ? + <First letter of a Group name>

If you hold down the three keys above, you can quickly jump to groups in the left (Groups and Files) page by pressing the first letter of a groups name. For example, Control ^Option ?Shift ?T takes you to Targets and Control ^Option ?Shift ?S to Source. Press it again and it jumps to SCM. Sometimes it takes several tries for this to work (I don't know why).


Cycling between autocompletion choices

  • Control ^ .

  • Shift ? Control ^ .: Cycles backwards between autocompletion choices.

Control ^. (Control-Period) after a word automatically accepts the first choice from the autocompletion menu. Try typing log then Control ^. and you'll get a nice NSLog statement. Press it again to cycle through any choices. To see all the mutable choices, type NSMu then Control ^..


Quick Help

  • Control ^ Command ? ? (While your cursor is in the symbol to look up)

  • Option ? + <Double-click a symbol>

  • Help > Quick Help

To get to the documentation from the Quick Help window, click the book icon on the top right.


See the documentation for a symbol

  • Command ? Option ? + <Double-click a symbol>

Takes you straight to the full documentation.


Make non-adjacent text selections

  • Command ? Control ^ + <Double-click in the editor>

Use the above shortcut for a strange way of selecting multiple words. You can make selections of words in totally different places, then delete or copy them all at once. Not sure if this is useful. It's Xcode only as far as I can tell.


Use Emacs key bindings to navigate through your code

This trick works in all Cocoa application on the Mac (TextEdit, Mail, etc.) and is possibly one of the most useful things to know.

  • Command ? Left Arrow or Command ? Right Arrow Takes you to the beginning and end of a line.
  • Control ^ a and Control ^ e Do the same thing
  • Control ^ n and Control ^ p Move the cursor up or down one line.
  • Control ^ f and Control ^ b Move the cursor back or forward one space

Pressing Shift ? with any of these selects the text between move points. Put the cursor in the middle of a line and press Shift ? Control ^ e and you can select to the end of the line.

Pressing Option ? will let you navigate words with the keyboard. Option ? Control ^ f skips to the end of the current word. Option ? Control ^ b skips to the beginning of the current word. You can also use Option ? with the left and right arrow keys to move one-word-at-a-time.

  • Control ^ Left Arrow and Control ^ Right Arrow moves the cursor between camel-cased parts of a word.

Try it with NSMutableArray. You can quickly change it to NSArray by putting your cursor after the NS, pressing Shift ? Control ^ Right Arrow then Delete.

Get the string representation of a DOM node

What you're looking for is 'outerHTML', but wee need a fallback coz it's not compatible with old browsers.

var getString = (function() {
  var DIV = document.createElement("div");

  if ('outerHTML' in DIV)
    return function(node) {
      return node.outerHTML;
    };

  return function(node) {
    var div = DIV.cloneNode();
    div.appendChild(node.cloneNode(true));
    return div.innerHTML;
  };

})();

// getString(el) == "<p>Test</p>"

You'll find my jQuery plugin here: Get selected element's outer HTML

How to run DOS/CMD/Command Prompt commands from VB.NET?

I was inspired by Steve's answer but thought I'd add a bit of flare to it. I like to do the work up front of writing extension methods so later I have less work to do calling the method.

For example with the modified version of Steve's answer below, instead of making this call...

MyUtilities.RunCommandCom("DIR", "/W", true)

I can actually just type out the command and call it from my strings like this...

Directly in code.

Call "CD %APPDATA% & TREE".RunCMD()

OR

From a variable.

Dim MyCommand = "CD %APPDATA% & TREE"
MyCommand.RunCMD()

OR

From a textbox.

textbox.text.RunCMD(WaitForProcessComplete:=True)


Extension methods will need to be placed in a Public Module and carry the <Extension> attribute over the sub. You will also want to add Imports System.Runtime.CompilerServices to the top of your code file.

There's plenty of info on SO about Extension Methods if you need further help.


Extension Method

Public Module Extensions
''' <summary>
''' Extension method to run string as CMD command.
''' </summary>
''' <param name="command">[String] Command to run.</param>
''' <param name="ShowWindow">[Boolean](Default:False) Option to show CMD window.</param>
''' <param name="WaitForProcessComplete">[Boolean](Default:False) Option to wait for CMD process to complete before exiting sub.</param>
''' <param name="permanent">[Boolean](Default:False) Option to keep window visible after command has finished. Ignored if ShowWindow is False.</param>
<Extension>
Public Sub RunCMD(command As String, Optional ShowWindow As Boolean = False, Optional WaitForProcessComplete As Boolean = False, Optional permanent As Boolean = False)
    Dim p As Process = New Process()
    Dim pi As ProcessStartInfo = New ProcessStartInfo()
    pi.Arguments = " " + If(ShowWindow AndAlso permanent, "/K", "/C") + " " + command
    pi.FileName = "cmd.exe"
    pi.CreateNoWindow = Not ShowWindow
    If ShowWindow Then
        pi.WindowStyle = ProcessWindowStyle.Normal
    Else
        pi.WindowStyle = ProcessWindowStyle.Hidden
    End If
    p.StartInfo = pi
    p.Start()
    If WaitForProcessComplete Then Do Until p.HasExited : Loop
End Sub
End Module

Easy way to convert Iterable to Collection

You can use Eclipse Collections factories:

Iterable<String> iterable = Arrays.asList("1", "2", "3");

MutableList<String> list = Lists.mutable.withAll(iterable);
MutableSet<String> set = Sets.mutable.withAll(iterable);
MutableSortedSet<String> sortedSet = SortedSets.mutable.withAll(iterable);
MutableBag<String> bag = Bags.mutable.withAll(iterable);
MutableSortedBag<String> sortedBag = SortedBags.mutable.withAll(iterable);

You can also convert the Iterable to a LazyIterable and use the converter methods or any of the other available APIs available.

Iterable<String> iterable = Arrays.asList("1", "2", "3");
LazyIterable<String> lazy = LazyIterate.adapt(iterable);

MutableList<String> list = lazy.toList();
MutableSet<String> set = lazy.toSet();
MutableSortedSet<String> sortedSet = lazy.toSortedSet();
MutableBag<String> bag = lazy.toBag();
MutableSortedBag<String> sortedBag = lazy.toSortedBag();

All of the above Mutable types extend java.util.Collection.

Note: I am a committer for Eclipse Collections.

How do I create a random alpha-numeric string in C++?

Here's a funny one-liner. Needs ASCII.

void gen_random(char *s, int l) {
    for (int c; c=rand()%62, *s++ = (c+"07="[(c+16)/26])*(l-->0););
}

How can I use pickle to save a dict?

import pickle

dictobj = {'Jack' : 123, 'John' : 456}

filename = "/foldername/filestore"

fileobj = open(filename, 'wb')

pickle.dump(dictobj, fileobj)

fileobj.close()

How can I measure the actual memory usage of an application or process?

I would suggest that you use atop. You can find everything about it on this page. It is capable of providing all the necessary KPI for your processes and it can also capture to a file.

What is the correct format to use for Date/Time in an XML file

If you are manually assembling the XML string use var.ToUniversalTime().ToString("yyyy-MM-dd'T'HH:mm:ss.fffffffZ")); That will output the official XML Date Time format. But you don't have to worry about format if you use the built-in serialization methods.

Set title background color

Thanks for this clear explanation, however I would like to add a bit more to your answer by asking a linked question (don't really want to do a new post as this one is the basement on my question).

I'm declaring my titlebar in a Superclass from which, all my other activities are children, to have to change the color of the bar only once. I would like to also add an icon and change the text in the bar. I have done some testing, and managed to change either one or the other but not both at the same time (using setFeatureDrawable and setTitle). The ideal solution would be of course to follow the explanation in the thread given in the link, but as i'm declaring in a superclass, i have an issue due to the layout in setContentView and the R.id.myCustomBar, because if i remember well i can call setContentView only once...

EDIT Found my answer :

For those who, like me, like to work with superclasses because it's great for getting a menu available everywhere in an app, it works the same here.

Just add this to your superclass:

requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
    setContentView(R.layout.customtitlebar);
    getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.customtitlebar);
    customTitleText = (TextView) findViewById(R.id.customtitlebar);

(you have to declare the textview as protected class variable)

And then the power of this is that, everywhere in you app (if for instance all your activities are children of this class), you just have to call

customTitleText.setText("Whatever you want in title");

and your titlebar will be edited.

The XML associated in my case is (R.layout.customtitlebar) :

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal" android:layout_width="fill_parent"
android:layout_height="fill_parent" android:background="@color/background">
<ImageView android:layout_width="25px" android:layout_height="25px"
    android:src="@drawable/icontitlebar"></ImageView>
<TextView android:id="@+id/customtitlebar"
    android:layout_width="wrap_content" android:layout_height="fill_parent"
    android:text="" android:textColor="@color/textcolor" android:textStyle="bold"
    android:background="@color/background" android:padding="3px" />
</LinearLayout>

How to configure PHP to send e-mail?

This will not work on a local host, but uploaded on a server, this code should do the trick. Just make sure to enter your own email address for the $to line.

<?php
if (isset($_POST['name']) && isset($_POST['email'])) {
    $name = $_POST['name'];
    $email = $_POST['email'];
    $to = '[email protected]';
    $subject = "New Message on YourWebsite.com";
    $body = '<html>
                <body>
                    <h2>Title</h2>
                    <br>
                    <p>Name:<br>'.$name.'</p>
                    <p>Email:<br>'.$email.'</p>

                </body>
            </html>';

//headers
$headers = "From: ".$name." <".$email.">\r\n";
$headers = "Reply-To: ".$email."\r\n";
$headers = "MIME-Version: 1.0\r\n";
$headers = "Content-type: text/html; charset=utf-8";

//send
$send = mail($to, $subject, $body, $headers);
if ($send) {
    echo '<br>';
    echo "Success. Thanks for Your Message.";
} else {
    echo 'Error.';
}
}
?>

<html>
    <head>
        <meta charset="utf-8">
    </head>
    <body>
        <form action="" method="post">
            <input type="text" name="name" placeholder="Your Name"><br>
            <input type="text" name="email" placeholder="Your Email"><br>
            <button type="submit">Subscribe</button>
        </form>
    </body>
</html>

Fixed header, footer with scrollable content

Approach 1 - flexbox

It works great for both known and unknown height elements. Make sure to set the outer div to height: 100%; and reset the default margin on body. See the browser support tables.

jsFiddle

_x000D_
_x000D_
html, body {_x000D_
  height: 100%;_x000D_
  margin: 0;_x000D_
}_x000D_
.wrapper {_x000D_
  height: 100%;_x000D_
  display: flex;_x000D_
  flex-direction: column;_x000D_
}_x000D_
.header, .footer {_x000D_
  background: silver;_x000D_
}_x000D_
.content {_x000D_
  flex: 1;_x000D_
  overflow: auto;_x000D_
  background: pink;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="header">Header</div>_x000D_
  <div class="content">_x000D_
    <div style="height:1000px;">Content</div>_x000D_
  </div>_x000D_
  <div class="footer">Footer</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Approach 2 - CSS table

For both known and unknown height elements. It also works in legacy browsers including IE8.

jsFiddle

_x000D_
_x000D_
html, body {_x000D_
  height: 100%;_x000D_
  margin: 0;_x000D_
}_x000D_
.wrapper {_x000D_
  height: 100%;_x000D_
  width: 100%;_x000D_
  display: table;_x000D_
}_x000D_
.header, .content, .footer {_x000D_
  display: table-row;_x000D_
}_x000D_
.header, .footer {_x000D_
  background: silver;_x000D_
}_x000D_
.inner {_x000D_
  display: table-cell;_x000D_
}_x000D_
.content .inner {_x000D_
  height: 100%;_x000D_
  position: relative;_x000D_
  background: pink;_x000D_
}_x000D_
.scrollable {_x000D_
  position: absolute;_x000D_
  left: 0; right: 0;_x000D_
  top: 0; bottom: 0;_x000D_
  overflow: auto;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="header">_x000D_
    <div class="inner">Header</div>_x000D_
  </div>_x000D_
  <div class="content">_x000D_
    <div class="inner">_x000D_
      <div class="scrollable">_x000D_
        <div style="height:1000px;">Content</div>_x000D_
      </div>_x000D_
    </div>_x000D_
  </div>_x000D_
  <div class="footer">_x000D_
    <div class="inner">Footer</div>_x000D_
  </div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Approach 3 - calc()

If header and footer are fixed height, you can use CSS calc().

jsFiddle

_x000D_
_x000D_
html, body {_x000D_
  height: 100%;_x000D_
  margin: 0;_x000D_
}_x000D_
.wrapper {_x000D_
  height: 100%;_x000D_
}_x000D_
.header, .footer {_x000D_
  height: 50px;_x000D_
  background: silver;_x000D_
}_x000D_
.content {_x000D_
  height: calc(100% - 100px);_x000D_
  overflow: auto;_x000D_
  background: pink;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="header">Header</div>_x000D_
  <div class="content">_x000D_
    <div style="height:1000px;">Content</div>_x000D_
  </div>_x000D_
  <div class="footer">Footer</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Approach 4 - % for all

If the header and footer are known height, and they are also percentage you can just do the simple math making them together of 100% height.

_x000D_
_x000D_
html, body {_x000D_
  height: 100%;_x000D_
  margin: 0;_x000D_
}_x000D_
.wrapper {_x000D_
  height: 100%;_x000D_
}_x000D_
.header, .footer {_x000D_
  height: 10%;_x000D_
  background: silver;_x000D_
}_x000D_
.content {_x000D_
  height: 80%;_x000D_
  overflow: auto;_x000D_
  background: pink;_x000D_
}
_x000D_
<div class="wrapper">_x000D_
  <div class="header">Header</div>_x000D_
  <div class="content">_x000D_
    <div style="height:1000px;">Content</div>_x000D_
  </div>_x000D_
  <div class="footer">Footer</div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

jsFiddle

How do disable paging by swiping with finger in ViewPager but still be able to swipe programmatically?

This worked for me

viewPager.setOnTouchListener(new View.OnTouchListener() {
                                         @Override
                                         public boolean onTouch(View v, MotionEvent event) {
                                             if (viewPager.getCurrentItem() == 0) {
                                                 viewPager.setCurrentItem(-1, false);
                                                 return true;
                                             }
                                             else if (viewPager.getCurrentItem() == 1) {
                                                 viewPager.setCurrentItem(1, false);
                                                 return true;
                                             }
                                             else if (viewPager.getCurrentItem() == 2) {
                                                 viewPager.setCurrentItem(2, false);
                                                 return true;
                                             }
                                             return true;
                                         }
                                     });

Sending email with attachments from C#, attachments arrive as Part 1.2 in Thunderbird

Completing the solution of Ranadheer, using Server.MapPath to locate the file

System.Net.Mail.Attachment attachment;
attachment = New System.Net.Mail.Attachment(Server.MapPath("~/App_Data/hello.pdf"));
mail.Attachments.Add(attachment);

How to check if a string starts with "_" in PHP?

$variable[0] != "_"

How does it work?

In PHP you can get particular character of a string with array index notation. $variable[0] is the first character of a string (if $variable is a string).

Change a branch name in a Git repo

Assuming you're currently on the branch you want to rename:

git branch -m newname

This is documented in the manual for git-branch, which you can view using

man git-branch

or

git help branch

Specifically, the command is

git branch (-m | -M) [<oldbranch>] <newbranch>

where the parameters are:

   <oldbranch>
       The name of an existing branch to rename.

   <newbranch>
       The new name for an existing branch. The same restrictions as for <branchname> apply.

<oldbranch> is optional, if you want to rename the current branch.

Normalize numpy array columns in python

You can use sklearn.preprocessing:

from sklearn.preprocessing import normalize
data = np.array([
    [1000, 10, 0.5],
    [765, 5, 0.35],
    [800, 7, 0.09], ])
data = normalize(data, axis=0, norm='max')
print(data)
>>[[ 1.     1.     1.   ]
[ 0.765  0.5    0.7  ]
[ 0.8    0.7    0.18 ]]

iPad Web App: Detect Virtual Keyboard Using JavaScript in Safari?

Edit: Documented by Apple although I couldn't actually get it to work: WKWebView Behavior with Keyboard Displays: "In iOS 10, WKWebView objects match Safari’s native behavior by updating their window.innerHeight property when the keyboard is shown, and do not call resize events" (perhaps can use focus or focus plus delay to detect keyboard instead of using resize).

Edit: code presumes onscreen keyboard, not external keyboard. Leaving it because info may be useful to others that only care about onscreen keyboards. Use http://jsbin.com/AbimiQup/4 to view page params.

We test to see if the document.activeElement is an element which shows the keyboard (input type=text, textarea, etc).

The following code fudges things for our purposes (although not generally correct).

function getViewport() {
    if (window.visualViewport && /Android/.test(navigator.userAgent)) {
        // https://developers.google.com/web/updates/2017/09/visual-viewport-api    Note on desktop Chrome the viewport subtracts scrollbar widths so is not same as window.innerWidth/innerHeight
        return {
            left: visualViewport.pageLeft,
            top: visualViewport.pageTop,
            width: visualViewport.width,
            height: visualViewport.height
        };
    }
    var viewport = {
            left: window.pageXOffset,   // http://www.quirksmode.org/mobile/tableViewport.html
            top: window.pageYOffset,
            width: window.innerWidth || documentElement.clientWidth,
            height: window.innerHeight || documentElement.clientHeight
    };
    if (/iPod|iPhone|iPad/.test(navigator.platform) && isInput(document.activeElement)) {       // iOS *lies* about viewport size when keyboard is visible. See http://stackoverflow.com/questions/2593139/ipad-web-app-detect-virtual-keyboard-using-javascript-in-safari Input focus/blur can indicate, also scrollTop: 
        return {
            left: viewport.left,
            top: viewport.top,
            width: viewport.width,
            height: viewport.height * (viewport.height > viewport.width ? 0.66 : 0.45)  // Fudge factor to allow for keyboard on iPad
        };
    }
    return viewport;
}


function isInput(el) {
    var tagName = el && el.tagName && el.tagName.toLowerCase();
    return (tagName == 'input' && el.type != 'button' && el.type != 'radio' && el.type != 'checkbox') || (tagName == 'textarea');
};

The above code is only approximate: It is wrong for split keyboard, undocked keyboard, physical keyboard. As per comment at top, you may be able to do a better job than the given code on Safari (since iOS8?) or WKWebView (since iOS10) using window.innerHeight property.

I have found failures under other circumstances: e.g. give focus to input then go to home screen then come back to page; iPad shouldnt make viewport smaller; old IE browsers won't work, Opera didnt work because Opera kept focus on element after keyboard closed.

However the tagged answer (changing scrolltop to measure height) has nasty UI side effects if viewport zoomable (or force-zoom enabled in preferences). I don't use the other suggested solution (changing scrolltop) because on iOS, when viewport is zoomable and scrolling to focused input, there are buggy interactions between scrolling & zoom & focus (that can leave a just focused input outside of viewport - not visible).

PDO support for multiple queries (PDO_MYSQL, PDO_MYSQLND)

As I know, PDO_MYSQLND replaced PDO_MYSQL in PHP 5.3. Confusing part is that name is still PDO_MYSQL. So now ND is default driver for MySQL+PDO.

Overall, to execute multiple queries at once you need:

  • PHP 5.3+
  • mysqlnd
  • Emulated prepared statements. Make sure PDO::ATTR_EMULATE_PREPARES is set to 1 (default). Alternatively you can avoid using prepared statements and use $pdo->exec directly.

Using exec

$db = new PDO("mysql:host=localhost;dbname=test", 'root', '');

// works regardless of statements emulation
$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, 0);

$sql = "
DELETE FROM car; 
INSERT INTO car(name, type) VALUES ('car1', 'coupe'); 
INSERT INTO car(name, type) VALUES ('car2', 'coupe');
";

$db->exec($sql);

Using statements

$db = new PDO("mysql:host=localhost;dbname=test", 'root', '');

// works not with the following set to 0. You can comment this line as 1 is default
$db->setAttribute(PDO::ATTR_EMULATE_PREPARES, 1);

$sql = "
DELETE FROM car; 
INSERT INTO car(name, type) VALUES ('car1', 'coupe'); 
INSERT INTO car(name, type) VALUES ('car2', 'coupe');
";

$stmt = $db->prepare($sql);
$stmt->execute();

A note:

When using emulated prepared statements, make sure you have set proper encoding (that reflects actual data encoding) in DSN (available since 5.3.6). Otherwise there can be a slight possibility for SQL injection if some odd encoding is used.

JPA : How to convert a native query result set to POJO class collection

I tried a lot of things as mentioned in the above answers. The SQLmapper was very confusing as to where to put it. Non managed POJOs only were a problem. I was trying various ways and one easy way I got it worked was as usual. I am using hibernate-jpa-2.1.

List<TestInfo> testInfoList = factory.createNativeQuery(QueryConstants.RUNNING_TEST_INFO_QUERY)
                    .getResultList();

The only thing to take care was that POJO has same member variable names as that of the query ( all in lowercase). And apparently I didn't even need to tell the target class along with query as we do with TypedQueries in JPQL.

TestInfo.class

@Setter
@Getter
@NoArgsConstructor
@ToString
public class TestInfo {

    private String emailid;
    private Long testcount;

    public TestInfo(String emailId, Long testCount) {
        super();
        this.emailid = emailId;
        this.testcount = testCount;
    }

}

ReSharper "Cannot resolve symbol" even when project builds

I tested ALL of the other answers in this page (before writing this answer) such as:

  1. VS -> Tools -> Options -> ReSharper Suspend button and Resume

  2. Clear ReSharper cache

  3. And others

But unfortunately none of them solved my problem. Maybe my problem was complicated than your problem. I said about them in my EDITs in the question, then the following answer was correct solution for me but maybe other answers solve your problem. please test them first.

I was forced to reinstall my OS and use a newer version of my tools. :(

Now i use VS 2013 + R# v8 and when i have any problem with my resharper i just try the following instruction and it solve my problems:

VS -> Tools -> Options -> ReSharper Suspend button and Resume

Reading a simple text file

This is how I do it:

public static String readFromAssets(Context context, String filename) throws IOException {
    BufferedReader reader = new BufferedReader(new InputStreamReader(context.getAssets().open(filename)));

    // do reading, usually loop until end of file reading  
    StringBuilder sb = new StringBuilder();
    String mLine = reader.readLine();
    while (mLine != null) {
        sb.append(mLine); // process line
        mLine = reader.readLine();
    }
    reader.close();
    return sb.toString();
}

use it as follows:

readFromAssets(context,"test.txt")

jQuery iframe load() event?

Without code in iframe + animate:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
<script language="javascript" type="text/javascript">

function resizeIframe(obj) {

    jQuery(document).ready(function($) {

        $(obj).animate({height: obj.contentWindow.document.body.scrollHeight + 'px'}, 500)

    });

}    
</script>
<iframe width="100%" src="iframe.html" height="0" frameborder="0" scrolling="no" onload="resizeIframe(this)" >

Gets byte array from a ByteBuffer in java

Note that the bb.array() doesn't honor the byte-buffers position, and might be even worse if the bytebuffer you are working on is a slice of some other buffer.

I.e.

byte[] test = "Hello World".getBytes("Latin1");
ByteBuffer b1 = ByteBuffer.wrap(test);
byte[] hello = new byte[6];
b1.get(hello); // "Hello "
ByteBuffer b2 = b1.slice(); // position = 0, string = "World"
byte[] tooLong = b2.array(); // Will NOT be "World", but will be "Hello World".
byte[] world = new byte[5];
b2.get(world); // world = "World"

Which might not be what you intend to do.

If you really do not want to copy the byte-array, a work-around could be to use the byte-buffer's arrayOffset() + remaining(), but this only works if the application supports index+length of the byte-buffers it needs.

How do I install ASP.NET MVC 5 in Visual Studio 2012?

Microsoft has provided for you on their MSDN blogs: MVC 5 for VS2012. From that blog:

We have released ASP.NET and Web Tools 2013.1 for Visual Studio 2012. This release brings a ton of great improvements, and include some fantastic enhancements to ASP.NET MVC 5, Web API 2, Scaffolding and Entity Framework to users of Visual Studio 2012 and Visual Studio 2012 Express for Web.

You can download and start using these features now.

The download link is to a Web Platform Installer that will allow you to start a new MVC5 project from VS2012.

How do I pass a list as a parameter in a stored procedure?

As far as I can tell, there are three main contenders: Table-Valued Parameters, delimited list string, and JSON string.

Since 2016, you can use the built-in STRING_SPLIT if you want the delimited route: https://docs.microsoft.com/en-us/sql/t-sql/functions/string-split-transact-sql

That would probably be the easiest/most straightforward/simple approach.

Also since 2016, JSON can be passed as a nvarchar and used with OPENJSON: https://docs.microsoft.com/en-us/sql/t-sql/functions/openjson-transact-sql

That's probably best if you have a more structured data set to pass that may be significantly variable in its schema.

TVPs, it seems, used to be the canonical way to pass more structured parameters, and they are still good if you need that structure, explicitness, and basic value/type checking. They can be a little more cumbersome on the consumer side, though. If you don't have 2016+, this is probably the default/best option.

I think it's a trade off between any of these concrete considerations as well as your preference for being explicit about the structure of your params, meaning even if you have 2016+, you may prefer to explicitly state the type/schema of the parameter rather than pass a string and parse it somehow.

How to diff one file to an arbitrary version in Git?

If you need to diff on a single file in a stash for example you can do

git diff stash@{0} -- path/to/file

SVN remains in conflict?

Instructions for Tortoise SVN

Navigate to the directory where you see this error. If you do not have any changes perform the following

a. Right click and do a 'Revert'
b. Select all the files
c. Then update the directory again

How to put the legend out of the plot

Short answer: you can use bbox_to_anchor + bbox_extra_artists + bbox_inches='tight'.


Longer answer: You can use bbox_to_anchor to manually specify the location of the legend box, as some other people have pointed out in the answers.

However, the usual issue is that the legend box is cropped, e.g.:

import matplotlib.pyplot as plt

# data 
all_x = [10,20,30]
all_y = [[1,3], [1.5,2.9],[3,2]]

# Plot
fig = plt.figure(1)
ax = fig.add_subplot(111)
ax.plot(all_x, all_y)

# Add legend, title and axis labels
lgd = ax.legend( [ 'Lag ' + str(lag) for lag in all_x], loc='center right', bbox_to_anchor=(1.3, 0.5))
ax.set_title('Title')
ax.set_xlabel('x label')
ax.set_ylabel('y label')

fig.savefig('image_output.png', dpi=300, format='png')

enter image description here

In order to prevent the legend box from getting cropped, when you save the figure you can use the parameters bbox_extra_artists and bbox_inches to ask savefig to include cropped elements in the saved image:

fig.savefig('image_output.png', bbox_extra_artists=(lgd,), bbox_inches='tight')

Example (I only changed the last line to add 2 parameters to fig.savefig()):

import matplotlib.pyplot as plt

# data 
all_x = [10,20,30]
all_y = [[1,3], [1.5,2.9],[3,2]]

# Plot
fig = plt.figure(1)
ax = fig.add_subplot(111)
ax.plot(all_x, all_y)

# Add legend, title and axis labels
lgd = ax.legend( [ 'Lag ' + str(lag) for lag in all_x], loc='center right', bbox_to_anchor=(1.3, 0.5))
ax.set_title('Title')
ax.set_xlabel('x label')
ax.set_ylabel('y label')    

fig.savefig('image_output.png', dpi=300, format='png', bbox_extra_artists=(lgd,), bbox_inches='tight')

enter image description here

I wish that matplotlib would natively allow outside location for the legend box as Matlab does:

figure
x = 0:.2:12;
plot(x,besselj(1,x),x,besselj(2,x),x,besselj(3,x));
hleg = legend('First','Second','Third',...
              'Location','NorthEastOutside')
% Make the text of the legend italic and color it brown
set(hleg,'FontAngle','italic','TextColor',[.3,.2,.1])

enter image description here

JavaScriptSerializer - JSON serialization of enum as string

new JavaScriptSerializer().Serialize(  
    (from p   
    in (new List<Person>() {  
        new Person()  
        {  
            Age = 35,  
            Gender = Gender.Male  
        }  
    })  
    select new { Age =p.Age, Gender=p.Gender.ToString() }  
    ).ToArray()[0]  
);

How to properly seed random number generator

just to toss it out for posterity: it can sometimes be preferable to generate a random string using an initial character set string. This is useful if the string is supposed to be entered manually by a human; excluding 0, O, 1, and l can help reduce user error.

var alpha = "abcdefghijkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ23456789"

// generates a random string of fixed size
func srand(size int) string {
    buf := make([]byte, size)
    for i := 0; i < size; i++ {
        buf[i] = alpha[rand.Intn(len(alpha))]
    }
    return string(buf)
}

and I typically set the seed inside of an init() block. They're documented here: http://golang.org/doc/effective_go.html#init

How to execute shell command in Javascript

Another post on this topic with a nice jQuery/Ajax/PHP solution:

shell scripting and jQuery

Angular 4 - Observable catch error

With angular 6 and rxjs 6 Observable.throw(), Observable.off() has been deprecated instead you need to use throwError

ex :

return this.http.get('yoururl')
  .pipe(
    map(response => response.json()),
    catchError((e: any) =>{
      //do your processing here
      return throwError(e);
    }),
  );

How to connect to MongoDB in Windows?

  1. Go to C:\Program Files\MongoDB\Server\3.4\bin using cmd and write mongod.
  2. Open another cmd by right click and run as admin point to your monogodb installed directory as mentioned above and then just like write this mongo.exe
  3. After that, write db.test.save({Field:'Hello mongodb'}) this command will insert a field having name Field and value is Hello mongodb.
  4. After, check the record db.test.find() and press enter you will find the record that you have recently entered.

Vertically centering a div inside another div

Vertically centering a div inside another div

_x000D_
_x000D_
#outerDiv{_x000D_
  width: 500px;_x000D_
  height: 500px;_x000D_
  position:relative;_x000D_
  _x000D_
  background-color: lightgrey;  _x000D_
}_x000D_
_x000D_
#innerDiv{_x000D_
  width: 284px;_x000D_
  height: 290px;_x000D_
  _x000D_
  position: absolute;_x000D_
  top: 50%;_x000D_
  left: 50%;_x000D_
  transform: translate(-50%, -50%);_x000D_
  -ms-transform: translate(-50%, -50%); /* IE 9 */_x000D_
  -webkit-transform: translate(-50%, -50%); /* Chrome, Safari, Opera */ _x000D_
  _x000D_
  background-color: grey;_x000D_
}
_x000D_
<div id="outerDiv">_x000D_
  <div id="innerDiv"></div>_x000D_
</div>
_x000D_
_x000D_
_x000D_

Python strptime() and timezones?

Since strptime returns a datetime object which has tzinfo attribute, We can simply replace it with desired timezone.

>>> import datetime

>>> date_time_str = '2018-06-29 08:15:27.243860'
>>> date_time_obj = datetime.datetime.strptime(date_time_str, '%Y-%m-%d %H:%M:%S.%f').replace(tzinfo=datetime.timezone.utc)
>>> date_time_obj.tzname()
'UTC'

Using subprocess to run Python script on Windows

Yes subprocess.Popen(cmd, ..., shell=True) works like a charm. On Windows the .py file extension is recognized, so Python is invoked to process it (on *NIX just the usual shebang). The path environment controls whether things are seen. So the first arg to Popen is just the name of the script.

subprocess.Popen(['myscript.py', 'arg1', ...], ..., shell=True)

Very Simple Image Slider/Slideshow with left and right button. No autoplay

Very simple code to make jquery slider Here is two div first is the slider viewer and second is the image list container. Just copy paste the code and customise with css.

    <div class="featured-image" style="height:300px">
     <img id="thumbnail" src="01.jpg"/>
    </div>

    <div class="post-margin" style="margin:10px 0px; padding:0px;" id="thumblist">
    <img src='01.jpg'>
    <img src='02.jpg'>
    <img src='03.jpg'>
    <img src='04.jpg'>
    </div>

    <script type="text/javascript">
            function changeThumbnail()
            {
            $("#thumbnail").fadeOut(200);
            var path=$("#thumbnail").attr('src');
            var arr= new Array(); var i=0;
            $("#thumblist img").each(function(index, element) {
               arr[i]=$(this).attr('src');
               i++;
            });
            var index= arr.indexOf(path);
            if(index==(arr.length-1))
            path=arr[0];
            else
            path=arr[index+1];
            $("#thumbnail").attr('src',path).fadeIn(200);
            setTimeout(changeThumbnail, 5000);  
            }
            setTimeout(changeThumbnail, 5000);
    </script>

Class method decorator with self arguments?

from re import search
from functools import wraps

def is_match(_lambda, pattern):
    def wrapper(f):
        @wraps(f)
        def wrapped(self, *f_args, **f_kwargs):
            if callable(_lambda) and search(pattern, (_lambda(self) or '')): 
                f(self, *f_args, **f_kwargs)
        return wrapped
    return wrapper

class MyTest(object):

    def __init__(self):
        self.name = 'foo'
        self.surname = 'bar'

    @is_match(lambda x: x.name, 'foo')
    @is_match(lambda x: x.surname, 'foo')
    def my_rule(self):
        print 'my_rule : ok'

    @is_match(lambda x: x.name, 'foo')
    @is_match(lambda x: x.surname, 'bar')
    def my_rule2(self):
        print 'my_rule2 : ok'



test = MyTest()
test.my_rule()
test.my_rule2()

ouput: my_rule2 : ok

How to check encoding of a CSV file

You can use Notepad++ to evaluate a file's encoding without needing to write code. The evaluated encoding of the open file will display on the bottom bar, far right side. The encodings supported can be seen by going to Settings -> Preferences -> New Document/Default Directory and looking in the drop down.

Can you display HTML5 <video> as a full screen background?

Just a comment on this - I've used HTML5 video for a full-screen background and it works a treat - but make sure to use either Height:100% and width:auto or the other way around - to ensure you keep aspect ratio.

As for Ipads -you can (apparently) do this, by having a hidden and then forcing the click event to fire, and having the function of the click event kick off the Load/Play().

P.s - this shouldn't require any plugins and can be done with minimal JS - If you're targeting any mobile device (I would assume you might be..) staying away from any such framework is the way forward.

HTTP URL Address Encoding in Java

a solution i developed and much more stable than any other:

public class URLParamEncoder {

    public static String encode(String input) {
        StringBuilder resultStr = new StringBuilder();
        for (char ch : input.toCharArray()) {
            if (isUnsafe(ch)) {
                resultStr.append('%');
                resultStr.append(toHex(ch / 16));
                resultStr.append(toHex(ch % 16));
            } else {
                resultStr.append(ch);
            }
        }
        return resultStr.toString();
    }

    private static char toHex(int ch) {
        return (char) (ch < 10 ? '0' + ch : 'A' + ch - 10);
    }

    private static boolean isUnsafe(char ch) {
        if (ch > 128 || ch < 0)
            return true;
        return " %$&+,/:;=?@<>#%".indexOf(ch) >= 0;
    }

}

What data is stored in Ephemeral Storage of Amazon EC2 instance?

Basically, root volume (your entire virtual system disk) is ephemeral, but only if you choose to create AMI backed by Amazon EC2 instance store.

If you choose to create AMI backed by EBS then your root volume is backed by EBS and everything you have on your root volume will be saved between reboots.

If you are not sure what type of volume you have, look under EC2->Elastic Block Store->Volumes in your AWS console and if your AMI root volume is listed there then you are safe. Also, if you go to EC2->Instances and then look under column "Root device type" of your instance and if it says "ebs", then you don't have to worry about data on your root device.

More details here: http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/RootDeviceStorage.html

What is `git push origin master`? Help with git's refs, heads and remotes

Git has two types of branches: local and remote. To use git pull and git push as you'd like, you have to tell your local branch (my_test) which remote branch it's tracking. In typical Git fashion this can be done in both the config file and with commands.

Commands

Make sure you're on your master branch with

1)git checkout master

then create the new branch with

2)git branch --track my_test origin/my_test

and check it out with

3)git checkout my_test.

You can then push and pull without specifying which local and remote.

However if you've already created the branch then you can use the -u switch to tell git's push and pull you'd like to use the specified local and remote branches from now on, like so:

git pull -u my_test origin/my_test
git push -u my_test origin/my_test

Config

The commands to setup remote branch tracking are fairly straight forward but I'm listing the config way as well as I find it easier if I'm setting up a bunch of tracking branches. Using your favourite editor open up your project's .git/config and add the following to the bottom.

[remote "origin"]
    url = [email protected]:username/repo.git
    fetch = +refs/heads/*:refs/remotes/origin/*
[branch "my_test"]
    remote = origin
    merge = refs/heads/my_test

This specifies a remote called origin, in this case a GitHub style one, and then tells the branch my_test to use it as it's remote.

You can find something very similar to this in the config after running the commands above.

Some useful resources:

How can I determine the direction of a jQuery scroll event?

I understand there has already been an accepted answer, but wanted to post what I am using in case it can help anyone. I get the direction like cliphex with the mousewheel event but with support for Firefox. It's useful doing it this way in case you are doing something like locking scroll and can't get the current scroll top.

See a live version here.

$(window).on('mousewheel DOMMouseScroll', function (e) {

    var direction = (function () {

        var delta = (e.type === 'DOMMouseScroll' ?
                     e.originalEvent.detail * -40 :
                     e.originalEvent.wheelDelta);

        return delta > 0 ? 0 : 1;
    }());

    if(direction === 1) {
       // scroll down
    }
    if(direction === 0) {
       // scroll up
    }
});

What is Express.js?

  1. What is Express.js?

Express.js is a Node.js web application server framework, designed for building single-page, multi-page, and hybrid web applications. It is the de facto standard server framework for node.js.

Frameworks built on Express.

Several popular Node.js frameworks are built on Express:

LoopBack: Highly-extensible, open-source Node.js framework for quickly creating dynamic end-to-end REST APIs.

Sails: MVC framework for Node.js for building practical, production-ready apps.

Kraken: Secure and scalable layer that extends Express by providing structure and convention.

MEAN: Opinionated fullstack JavaScript framework that simplifies and accelerates web application development.

  1. What is the purpose of it with Node.js?
  2. Why do we actually need Express.js? How it is useful for us to use with Node.js?

Express adds dead simple routing and support for Connect middleware, allowing many extensions and useful features.

For example,

  • Want sessions? It's there
  • Want POST body / query string parsing? It's there
  • Want easy templating through jade, mustache, ejs, etc? It's there
  • Want graceful error handling that won't cause the entire server to crash?

Switch on Enum in Java

Actually you can use a switch statement with Strings in Java...unfortunately this is a new feature of Java 7, and most people are not using Java 7 yet because it's so new.

CSS background-image-opacity?

Try this trick .. use css shadow with (inset) option and make the deep 200px for example

Code:

box-shadow: inset 0px 0px 277px 3px #4c3f37;

.

Also for all browsers:

-moz-box-shadow: inset 0px 0px 47px 3px #4c3f37;
-webkit-box-shadow: inset 0px 0px 47px 3px #4c3f37;
box-shadow: inset 0px 0px 277px 3px #4c3f37;

and increase number to make fill your box :)

Enjoy!

SQL Query Multiple Columns Using Distinct on One Column Only

select * from 
(select 
ROW_NUMBER() OVER(PARTITION BY tblFruit_FruitType ORDER BY tblFruit_FruitType DESC) as tt
,*
from tblFruit
) a
where a.tt=1

laravel 5.5 The page has expired due to inactivity. Please refresh and try again

In my case, there was 'space' before <?php in one of my config file. This solved my issue.

Adding a leading zero to some values in column in MySQL

Change the field back to numeric and use ZEROFILL to keep the zeros

or

use LPAD()

SELECT LPAD('1234567', 8, '0');

Flutter: RenderBox was not laid out

Reason for the error:

Column tries to expands in vertical axis, and so does the ListView, hence you need to constrain the height of ListView.


Solutions

  1. Use either Expanded or Flexible if you want to allow ListView to take up entire left space in Column.

    Column(
      children: <Widget>[
        Expanded(
          child: ListView(...),
        )
      ],
    )
    

  1. Use SizedBox if you want to restrict the size of ListView to a certain height.

    Column(
      children: <Widget>[
        SizedBox(
          height: 200, // constrain height
          child: ListView(),
        )
      ],
    )
    

  1. Use shrinkWrap, if your ListView isn't too big.

    Column(
      children: <Widget>[
        ListView(
          shrinkWrap: true, // use it
        )
      ],
    )
    

Comparing two vectors in an if statement

all is one option:

> A <- c("A", "B", "C", "D")
> B <- A
> C <- c("A", "C", "C", "E")

> all(A==B)
[1] TRUE
> all(A==C)
[1] FALSE

But you may have to watch out for recycling:

> D <- c("A","B","A","B")
> E <- c("A","B")
> all(D==E)
[1] TRUE
> all(length(D)==length(E)) && all(D==E)
[1] FALSE

The documentation for length says it currently only outputs an integer of length 1, but that it may change in the future, so that's why I wrapped the length test in all.

How to print exact sql query in zend framework ?

You can use Zend_Debug::Dump($select->assemble()); to get the SQL query.

Or you can enable Zend DB FirePHP profiler which will get you all queries in a neat format in Firebug (even UPDATE statements).

EDIT: Profiling with FirePHP also works also in FF6.0+ (not only in FF3.0 as suggested in link)

IIS w3svc error

I managed to solve after:

  1. Ctrl+Shift+Esc = To open Task Manager
  2. In the "Processes" tab locate the "IIS Worker Process" and finish it!
  3. Run on cmd as an administrator. Type iisreset.

Ready! Be happy!

Why would we call cin.clear() and cin.ignore() after reading input?

Why do we use:

1) cin.ignore

2) cin.clear

?

Simply:

1) To ignore (extract and discard) values that we don't want on the stream

2) To clear the internal state of stream. After using cin.clear internal state is set again back to goodbit, which means that there are no 'errors'.

Long version:

If something is put on 'stream' (cin) then it must be taken from there. By 'taken' we mean 'used', 'removed', 'extracted' from stream. Stream has a flow. The data is flowing on cin like water on stream. You simply cannot stop the flow of water ;)

Look at the example:

string name; //line 1
cout << "Give me your name and surname:"<<endl;//line 2
cin >> name;//line 3
int age;//line 4
cout << "Give me your age:" <<endl;//line 5
cin >> age;//line 6

What happens if the user answers: "Arkadiusz Wlodarczyk" for first question?

Run the program to see for yourself.

You will see on console "Arkadiusz" but program won't ask you for 'age'. It will just finish immediately right after printing "Arkadiusz".

And "Wlodarczyk" is not shown. It seems like if it was gone (?)*

What happened? ;-)

Because there is a space between "Arkadiusz" and "Wlodarczyk".

"space" character between the name and surname is a sign for computer that there are two variables waiting to be extracted on 'input' stream.

The computer thinks that you are tying to send to input more than one variable. That "space" sign is a sign for him to interpret it that way.

So computer assigns "Arkadiusz" to 'name' (2) and because you put more than one string on stream (input) computer will try to assign value "Wlodarczyk" to variable 'age' (!). The user won't have a chance to put anything on the 'cin' in line 6 because that instruction was already executed(!). Why? Because there was still something left on stream. And as I said earlier stream is in a flow so everything must be removed from it as soon as possible. And the possibility came when computer saw instruction cin >> age;

Computer doesn't know that you created a variable that stores age of somebody (line 4). 'age' is merely a label. For computer 'age' could be as well called: 'afsfasgfsagasggas' and it would be the same. For him it's just a variable that he will try to assign "Wlodarczyk" to because you ordered/instructed computer to do so in line (6).

It's wrong to do so, but hey it's you who did it! It's your fault! Well, maybe user, but still...


All right all right. But how to fix it?!

Let's try to play with that example a bit before we fix it properly to learn a few more interesting things :-)

I prefer to make an approach where we understand things. Fixing something without knowledge how we did it doesn't give satisfaction, don't you think? :)

string name;
cout << "Give me your name and surname:"<<endl;
cin >> name;
int age;
cout << "Give me your age:" <<endl;
cin >> age;
cout << cin.rdstate(); //new line is here :-)

After invoking above code you will notice that the state of your stream (cin) is equal to 4 (line 7). Which means its internal state is no longer equal to goodbit. Something is messed up. It's pretty obvious, isn't it? You tried to assign string type value ("Wlodarczyk") to int type variable 'age'. Types doesn't match. It's time to inform that something is wrong. And computer does it by changing internal state of stream. It's like: "You f**** up man, fix me please. I inform you 'kindly' ;-)"

You simply cannot use 'cin' (stream) anymore. It's stuck. Like if you had put big wood logs on water stream. You must fix it before you can use it. Data (water) cannot be obtained from that stream(cin) anymore because log of wood (internal state) doesn't allow you to do so.

Oh so if there is an obstacle (wood logs) we can just remove it using tools that is made to do so?

Yes!

internal state of cin set to 4 is like an alarm that is howling and making noise.

cin.clear clears the state back to normal (goodbit). It's like if you had come and silenced the alarm. You just put it off. You know something happened so you say: "It's OK to stop making noise, I know something is wrong already, shut up (clear)".

All right let's do so! Let's use cin.clear().

Invoke below code using "Arkadiusz Wlodarczyk" as first input:

string name;
cout << "Give me your name and surname:"<<endl;
cin >> name;
int age;
cout << "Give me your age:" <<endl;
cin >> age;
cout << cin.rdstate() << endl; 
cin.clear(); //new line is here :-)
cout << cin.rdstate()<< endl;  //new line is here :-)

We can surely see after executing above code that the state is equal to goodbit.

Great so the problem is solved?

Invoke below code using "Arkadiusz Wlodarczyk" as first input:

string name;
cout << "Give me your name and surname:"<<endl;
cin >> name;
int age;
cout << "Give me your age:" <<endl;
cin >> age;
cout << cin.rdstate() << endl;; 
cin.clear(); 
cout << cin.rdstate() << endl; 
cin >> age;//new line is here :-)

Even tho the state is set to goodbit after line 9 the user is not asked for "age". The program stops.

WHY?!

Oh man... You've just put off alarm, what about the wood log inside a water?* Go back to text where we talked about "Wlodarczyk" how it supposedly was gone.

You need to remove "Wlodarczyk" that piece of wood from stream. Turning off alarms doesn't solve the problem at all. You've just silenced it and you think the problem is gone? ;)

So it's time for another tool:

cin.ignore can be compared to a special truck with ropes that comes and removes the wood logs that got the stream stuck. It clears the problem the user of your program created.

So could we use it even before making the alarm goes off?

Yes:

string name;
cout << "Give me your name and surname:"<< endl;
cin >> name;
cin.ignore(10000, '\n'); //time to remove "Wlodarczyk" the wood log and make the stream flow
int age;
cout << "Give me your age:" << endl;
cin >> age;

The "Wlodarczyk" is gonna be removed before making the noise in line 7.

What is 10000 and '\n'?

It says remove 10000 characters (just in case) until '\n' is met (ENTER). BTW It can be done better using numeric_limits but it's not the topic of this answer.


So the main cause of problem is gone before noise was made...

Why do we need 'clear' then?

What if someone had asked for 'give me your age' question in line 6 for example: "twenty years old" instead of writing 20?

Types doesn't match again. Computer tries to assign string to int. And alarm starts. You don't have a chance to even react on situation like that. cin.ignore won't help you in case like that.

So we must use clear in case like that:

string name;
cout << "Give me your name and surname:"<< endl;
cin >> name;
cin.ignore(10000, '\n'); //time to remove "Wlodarczyk" the wood log and make the stream flow
int age;
cout << "Give me your age:" << endl;
cin >> age;
cin.clear();
cin.ignore(10000, '\n'); //time to remove "Wlodarczyk" the wood log and make the stream flow

But should you clear the state 'just in case'?

Of course not.

If something goes wrong (cin >> age;) instruction is gonna inform you about it by returning false.

So we can use conditional statement to check if the user put wrong type on the stream

int age;
if (cin >> age) //it's gonna return false if types doesn't match
    cout << "You put integer";
else
    cout << "You bad boy! it was supposed to be int";

All right so we can fix our initial problem like for example that:

string name;
cout << "Give me your name and surname:"<< endl;
cin >> name;
cin.ignore(10000, '\n'); //time to remove "Wlodarczyk" the wood log and make the stream flow

int age;
cout << "Give me your age:" << endl;
if (cin >> age)
  cout << "Your age is equal to:" << endl;
else
{
 cin.clear();
 cin.ignore(10000, '\n'); //time to remove "Wlodarczyk" the wood log and make the stream flow
 cout << "Give me your age name as string I dare you";
 cin >> age;
}

Of course this can be improved by for example doing what you did in question using loop while.

BONUS:

You might be wondering. What about if I wanted to get name and surname in the same line from the user? Is it even possible using cin if cin interprets each value separated by "space" as different variable?

Sure, you can do it two ways:

1)

string name, surname;
cout << "Give me your name and surname:"<< endl;
cin >> name;
cin >> surname;

cout << "Hello, " << name << " " << surname << endl;

2) or by using getline function.

getline(cin, nameOfStringVariable);

and that's how to do it:

string nameAndSurname;
cout << "Give me your name and surname:"<< endl;
getline(cin, nameAndSurname);

cout << "Hello, " << nameAndSurname << endl;

The second option might backfire you in case you use it after you use 'cin' before the getline.

Let's check it out:

a)

int age;
cout << "Give me your age:" <<endl;
cin >> age;
cout << "Your age is" << age << endl;

string nameAndSurname;
cout << "Give me your name and surname:"<< endl;
getline(cin, nameAndSurname);

cout << "Hello, " << nameAndSurname << endl;

If you put "20" as age you won't be asked for nameAndSurname.

But if you do it that way:

b)

string nameAndSurname;
cout << "Give me your name and surname:"<< endl;
getline(cin, nameAndSurname);

cout << "Hello, " << nameAndSurname << endl;
int age;
cout << "Give me your age:" <<endl;
cin >> age;
cout << "Your age is" << age << endll

everything is fine.

WHAT?!

Every time you put something on input (stream) you leave at the end white character which is ENTER ('\n') You have to somehow enter values to console. So it must happen if the data comes from user.

b) cin characteristics is that it ignores whitespace, so when you are reading in information from cin, the newline character '\n' doesn't matter. It gets ignored.

a) getline function gets the entire line up to the newline character ('\n'), and when the newline char is the first thing the getline function gets '\n', and that's all to get. You extract newline character that was left on stream by user who put "20" on stream in line 3.

So in order to fix it is to always invoke cin.ignore(); each time you use cin to get any value if you are ever going to use getline() inside your program.

So the proper code would be:

int age;
cout << "Give me your age:" <<endl;
cin >> age;
cin.ignore(); // it ignores just enter without arguments being sent. it's same as cin.ignore(1, '\n') 
cout << "Your age is" << age << endl;


string nameAndSurname;
cout << "Give me your name and surname:"<< endl;
getline(cin, nameAndSurname);

cout << "Hello, " << nameAndSurname << endl;

I hope streams are more clear to you know.

Hah silence me please! :-)

Is Java's assertEquals method reliable?

You should always use .equals() when comparing Strings in Java.

JUnit calls the .equals() method to determine equality in the method assertEquals(Object o1, Object o2).

So, you are definitely safe using assertEquals(string1, string2). (Because Strings are Objects)

Here is a link to a great Stackoverflow question regarding some of the differences between == and .equals().

How to overcome TypeError: unhashable type: 'list'

    python 3.2

    with open("d://test.txt") as f:
              k=(((i.split("\n"))[0].rstrip()).split() for i in f.readlines())
              d={}
              for i,_,v in k:
                      d.setdefault(i,[]).append(v)

SSL handshake fails with - a verisign chain certificate - that contains two CA signed certificates and one self-signed certificate

It sounds like the intermediate certificate is missing. As of April 2006, all SSL certificates issued by VeriSign require the installation of an Intermediate CA Certificate.

It could be that you don't have the entire certificate chain loaded on your server. Some businesses do not allow their computers to download additional certificates, causing a failure to complete an SSL handshake.

Here is some information on intermediate chains:
https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&id=AR657
https://knowledge.verisign.com/support/ssl-certificates-support/index?page=content&id=AD146

Intermediate CA Certificates

Trust Anchor not found for Android SSL Connection

The solution of @Chrispix is dangerous! Trusting all certificates allows anybody to do a man in the middle attack! Just send ANY certificate to the client and it will accept it!

Add your certificate(s) to a custom trust manager like described in this post: Trusting all certificates using HttpClient over HTTPS

Although it is a bit more complex to establish a secure connection with a custom certificate, it will bring you the wanted ssl encryption security without the danger of man in the middle attack!

Xcode 6: Keyboard does not show up in simulator

I had the same issue. My solution was as follows:

  1. iOS Simulator -> Hardware -> Keyboard
  2. Uncheck "Connect Hardware Keyboard"

Mine was checked because I was using my mac keyboard, but if you make sure it is unchecked the iPhone keyboard will always come up.

Trim specific character from a string

I would suggest looking at lodash and how they implemented the trim function.

See Lodash Trim for the documentation and the source to see the exact code that does the trimming.

I know this does not provide an exact answer your question, but I think it's good to set a reference to a library on such a question since others might find it useful.

Checking that a List is not empty in Hamcrest

If you're after readable fail messages, you can do without hamcrest by using the usual assertEquals with an empty list:

assertEquals(new ArrayList<>(0), yourList);

E.g. if you run

assertEquals(new ArrayList<>(0), Arrays.asList("foo", "bar");

you get

java.lang.AssertionError
Expected :[]
Actual   :[foo, bar]

"SyntaxError: Unexpected token < in JSON at position 0"

In my Case there was problem with "Bearer" in header ideally it should be "Bearer "(space after the end character) but in my case it was "Bearer" there was no space after the character. Hope it helps some one!

How do you echo a 4-digit Unicode character in Bash?

% echo -e '\u2620'     # \u takes four hexadecimal digits
?
% echo -e '\U0001f602' # \U takes eight hexadecimal digits

This works in Zsh (I've checked version 4.3) and in Bash 4.2 or newer.

Convert Python program to C/C++ code?

I know this is an older thread but I wanted to give what I think to be helpful information.

I personally use PyPy which is really easy to install using pip. I interchangeably use Python/PyPy interpreter, you don't need to change your code at all and I've found it to be roughly 40x faster than the standard python interpreter (Either Python 2x or 3x). I use pyCharm Community Edition to manage my code and I love it.

I like writing code in python as I think it lets you focus more on the task than the language, which is a huge plus for me. And if you need it to be even faster, you can always compile to a binary for Windows, Linux, or Mac (not straight forward but possible with other tools). From my experience, I get about 3.5x speedup over PyPy when compiling, meaning 140x faster than python. PyPy is available for Python 3x and 2x code and again if you use an IDE like PyCharm you can interchange between say PyPy, Cython, and Python very easily (takes a little of initial learning and setup though).

Some people may argue with me on this one, but I find PyPy to be faster than Cython. But they're both great choices though.

Edit: I'd like to make another quick note about compiling: when you compile, the resulting binary is much bigger than your python script as it builds all dependencies into it, etc. But then you get a few distinct benefits: speed!, now the app will work on any machine (depending on which OS you compiled for, if not all. lol) without Python or libraries, it also obfuscates your code and is technically 'production' ready (to a degree). Some compilers also generate C code, which I haven't really looked at or seen if it's useful or just gibberish. Good luck.

Hope that helps.

Centos/Linux setting logrotate to maximum file size for all logs

As mentioned by Zeeshan, the logrotate options size, minsize, maxsize are triggers for rotation.

To better explain it. You can run logrotate as often as you like, but unless a threshold is reached such as the filesize being reached or the appropriate time passed, the logs will not be rotated.

The size options do not ensure that your rotated logs are also of the specified size. To get them to be close to the specified size you need to call the logrotate program sufficiently often. This is critical.

For log files that build up very quickly (e.g. in the hundreds of MB a day), unless you want them to be very large you will need to ensure logrotate is called often! this is critical.

Therefore to stop your disk filling up with multi-gigabyte log files you need to ensure logrotate is called often enough, otherwise the log rotation will not work as well as you want.

on Ubuntu, you can easily switch to hourly rotation by moving the script /etc/cron.daily/logrotate to /etc/cron.hourly/logrotate

Or add

*/5 * * * * /etc/cron.daily/logrotate 

To your /etc/crontab file. To run it every 5 minutes.

The size option ignores the daily, weekly, monthly time options. But minsize & maxsize take it into account.

The man page is a little confusing there. Here's my explanation.

minsize rotates only when the file has reached an appropriate size and the set time period has passed. e.g. minsize 50MB + daily If file reaches 50MB before daily time ticked over, it'll keep growing until the next day.

maxsize will rotate when the log reaches a set size or the appropriate time has passed. e.g. maxsize 50MB + daily. If file is 50MB and we're not at the next day yet, the log will be rotated. If the file is only 20MB and we roll over to the next day then the file will be rotated.

size will rotate when the log > size. Regardless of whether hourly/daily/weekly/monthly is specified. So if you have size 100M - it means when your log file is > 100M the log will be rotated if logrotate is run when this condition is true. Once it's rotated, the main log will be 0, and a subsequent run will do nothing.

So in the op's case. Specficially 50MB max I'd use something like the following:

/var/log/logpath/*.log {
    maxsize 50M
    hourly
    missingok
    rotate 8
    compress
    notifempty
    nocreate
}

Which means he'd create 8hrs of logs max. And there would be 8 of them at no more than 50MB each. Since he's saying that he's getting multi gigabytes each day and assuming they build up at a fairly constant rate, and maxsize is used he'll end up with around close to the max reached for each file. So they will be likely close to 50MB each. Given the volume they build, he would need to ensure that logrotate is run often enough to meet the target size.

Since I've put hourly there, we'd need logrotate to be run a minimum of every hour. But since they build up to say 2 gigabytes per day and we want 50MB... assuming a constant rate that's 83MB per hour. So you can imagine if we run logrotate every hour, despite setting maxsize to 50 we'll end up with 83MB log's in that case. So in this instance set the running to every 30 minutes or less should be sufficient.

Ensure logrotate is run every 30 mins.

*/30 * * * * /etc/cron.daily/logrotate