Programs & Examples On #Audiotoolbox

The Audio Toolbox framework provides interfaces for recording, playback, and stream parsing. In iOS, the framework provides additional interfaces for managing audio sessions.

Undefined symbols for architecture i386

well i found a solution to this problem for who want to work with xCode 4. All what you have to do is importing frameworks from the SimulatorSDK folder /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator4.3.sdk/System/Library/Frameworks

i don't know if it works when you try to test your app on a real iDevice, but i'm sure that it works on simulator.

ENJOY

Apple Mach-O Linker Error when compiling for device

Try to clean your project, and Compile.

how to run vibrate continuously in iphone?

iOS 5 has implemented Custom Vibrations mode. So in some cases variable vibration is acceptable. The only thing is unknown what library deals with that (pretty sure not CoreTelephony) and if it is open for developers. So keep on searching.

What is considered a good response time for a dynamic, personalized web application?

We strive for response times of 20 milliseconds, while some complex pages take up to 100 milliseconds. For the most complex pages, we break the page down into smaller pieces, and use the progressive display pattern to load each section. This way, some portions load quickly, even if the page takes 1 to 2 seconds to load, keeping the user engaged while the rest of the page is loading.

How do I determine scrollHeight?

Correct ways in jQuery are -

  • $('#test').prop('scrollHeight') OR
  • $('#test')[0].scrollHeight OR
  • $('#test').get(0).scrollHeight

Cannot read property 'addEventListener' of null

I've a collection of quotes along with names. I'm using update button to update the last quote associated with a specific name but on clicking update button it's not updating. I'm including code below for server.js file and external js file (main.js).

main.js (external js)

var update = document.getElementById('update');
if (update){
update.addEventListener('click', function () {

  fetch('quotes', {
  method: 'put',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    'name': 'Muskan',
    'quote': 'I find your lack of faith disturbing.'
  })
})var update = document.getElementById('update');
if (update){
update.addEventListener('click', function () {

  fetch('quotes', {
  method: 'put',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    'name': 'Muskan',
    'quote': 'I find your lack of faith disturbing.'
  })
})
.then(res =>{
    if(res.ok) return res.json()
})
.then(data =>{
    console.log(data);
    window.location.reload(true);
})
})
}

server.js file

app.put('/quotes', (req, res) => {
  db.collection('quotations').findOneAndUpdate({name: 'Vikas'},{
    $set:{
        name: req.body.name,
        quote: req.body.quote
    }
  },{
    sort: {_id: -1},
    upsert: true
  },(err, result) =>{
    if (err) return res.send(err);
    res.send(result);
  })

})

What do numbers using 0x notation mean?

In C and languages based on the C syntax, the prefix 0x means hexadecimal (base 16).

Thus, 0x400 = 4×(162) + 0×(161) + 0×(160) = 4×((24)2) = 22 × 28 = 210 = 1024, or one binary K.

And so 0x6400 = 0x4000 + 0x2400 = 0x19×0x400 = 25K

Is there a way to pass javascript variables in url?

Do you mean include javascript variable values in the query string of the URL?

Yes:

 window.location.href = "http://www.gorissen.info/Pierre/maps/googleMapLocation.php?lat="+var1+"&lon="+var2+"&setLatLon="+varEtc;

javascript: get a function's variable's value within another function

Your nameContent variable is inside the function scope and not visible outside that function so if you want to use the nameContent outside of the function then declare it global inside the <script> tag and use inside functions without the var keyword as follows

<script language="javascript" type="text/javascript">
    var nameContent; // In the global scope
    function first(){
        nameContent=document.getElementById('full_name').value;
    }

    function second() {
        first();
        y=nameContent; 
        alert(y);
    }
    second();
</script>

Find full path of the Python interpreter?

Just noting a different way of questionable usefulness, using os.environ:

import os
python_executable_path = os.environ['_']

e.g.

$ python -c "import os; print(os.environ['_'])"
/usr/bin/python

PHP to search within txt file and echo the whole line

$searchfor = $_GET['keyword'];
$file = 'users.txt';

$contents = file_get_contents($file);
$pattern = preg_quote($searchfor, '/');
$pattern = "/^.*$pattern.*\$/m";

if (preg_match_all($pattern, $contents, $matches)) {
    echo "Found matches:<br />";
    echo implode("<br />", $matches[0]);
} else {
    echo "No matches found";
    fclose ($file); 
}

Creating a ZIP archive in memory using System.IO.Compression

This is the way to convert a entity to XML File and then compress it:

private  void downloadFile(EntityXML xml) {

string nameDownloadXml = "File_1.xml";
string nameDownloadZip = "File_1.zip";

var serializer = new XmlSerializer(typeof(EntityXML));

Response.Clear();
Response.ClearContent();
Response.ClearHeaders();
Response.AddHeader("content-disposition", "attachment;filename=" + nameDownloadZip);

using (var memoryStream = new MemoryStream())
{
    using (var archive = new ZipArchive(memoryStream, ZipArchiveMode.Create, true))
    {
        var demoFile = archive.CreateEntry(nameDownloadXml);
        using (var entryStream = demoFile.Open())
        using (StreamWriter writer = new StreamWriter(entryStream, System.Text.Encoding.UTF8))
        {
            serializer.Serialize(writer, xml);
        }
    }

    using (var fileStream = Response.OutputStream)
    {
        memoryStream.Seek(0, SeekOrigin.Begin);
        memoryStream.CopyTo(fileStream);
    }
}

Response.End();

}

How do I automatically play a Youtube video (IFrame API) muted?

Try this its working fine

_x000D_
_x000D_
<html><body style='margin:0px;padding:0px;'>_x000D_
        <script type='text/javascript' src='http://www.youtube.com/iframe_api'></script><script type='text/javascript'>_x000D_
                var player;_x000D_
        function onYouTubeIframeAPIReady()_x000D_
        {player=new YT.Player('playerId',{events:{onReady:onPlayerReady}})}_x000D_
        function onPlayerReady(event){player.mute();player.setVolume(0);player.playVideo();}_x000D_
        </script>_x000D_
        <iframe id='playerId' type='text/html' width='1280' height='720'_x000D_
        src='https://www.youtube.com/embed/R52bof3tvZs?enablejsapi=1&rel=0&playsinline=1&autoplay=1&showinfo=0&autohide=1&controls=0&modestbranding=1' frameborder='0'>_x000D_
        </body></html>
_x000D_
_x000D_
_x000D_

Concatenating null strings in Java

You are not using the "null" and therefore you don't get the exception. If you want the NullPointer, just do

String s = null;
s = s.toString() + "hello";

And I think what you want to do is:

String s = "";
s = s + "hello";

PDF to byte array and vice versa

You basically need a helper method to read a stream into memory. This works pretty well:

public static byte[] readFully(InputStream stream) throws IOException
{
    byte[] buffer = new byte[8192];
    ByteArrayOutputStream baos = new ByteArrayOutputStream();

    int bytesRead;
    while ((bytesRead = stream.read(buffer)) != -1)
    {
        baos.write(buffer, 0, bytesRead);
    }
    return baos.toByteArray();
}

Then you'd call it with:

public static byte[] loadFile(String sourcePath) throws IOException
{
    InputStream inputStream = null;
    try 
    {
        inputStream = new FileInputStream(sourcePath);
        return readFully(inputStream);
    } 
    finally
    {
        if (inputStream != null)
        {
            inputStream.close();
        }
    }
}

Don't mix up text and binary data - it only leads to tears.

How to use std::sort to sort an array in C++

In C++0x/11 we get std::begin and std::end which are overloaded for arrays:

#include <algorithm>

int main(){
  int v[2000];
  std::sort(std::begin(v), std::end(v));
}

If you don't have access to C++0x, it isn't hard to write them yourself:

// for container with nested typedefs, non-const version
template<class Cont>
typename Cont::iterator begin(Cont& c){
  return c.begin();
}

template<class Cont>
typename Cont::iterator end(Cont& c){
  return c.end();
}

// const version
template<class Cont>
typename Cont::const_iterator begin(Cont const& c){
  return c.begin();
}

template<class Cont>
typename Cont::const_iterator end(Cont const& c){
  return c.end();
}

// overloads for C style arrays
template<class T, std::size_t N>
T* begin(T (&arr)[N]){
  return &arr[0];
}

template<class T, std::size_t N>
T* end(T (&arr)[N]){
  return arr + N;
}

JFrame: How to disable window resizing?

This Code May be Help you : [ Both maximizing and preventing resizing on a JFrame ]

frame.setExtendedState(JFrame.MAXIMIZED_BOTH);
frame.setVisible(true);
frame.setResizable(false);

Why is my CSS style not being applied?

There could be an error earlier in the CSS file that is causing your (correct) CSS to not work.

Inheriting from a template class in c++

For understanding templates, it's of huge advantage to get the terminology straight because the way you speak about them determines the way to think about them.

Specifically, Area is not a template class, but a class template. That is, it is a template from which classes can be generated. Area<int> is such a class (it's not an object, but of course you can create an object from that class in the same ways you can create objects from any other class). Another such class would be Area<char>. Note that those are completely different classes, which have nothing in common except for the fact that they were generated from the same class template.

Since Area is not a class, you cannot derive the class Rectangle from it. You only can derive a class from another class (or several of them). Since Area<int> is a class, you could, for example, derive Rectangle from it:

class Rectangle:
  public Area<int>
{
  // ...
};

Since Area<int> and Area<char> are different classes, you can even derive from both at the same time (however when accessing members of them, you'll have to deal with ambiguities):

class Rectangle:
  public Area<int>,
  public Area<char>
{
  // ...
};

However you have to specify which classed to derive from when you define Rectangle. This is true no matter whether those classes are generated from a template or not. Two objects of the same class simply cannot have different inheritance hierarchies.

What you can do is to make Rectangle a template as well. If you write

template<typename T> class Rectangle:
  public Area<T>
{
  // ...
};

You have a template Rectangle from which you can get a class Rectangle<int> which derives from Area<int>, and a different class Rectangle<char> which derives from Area<char>.

It may be that you want to have a single type Rectangle so that you can pass all sorts of Rectangle to the same function (which itself doesn't need to know the Area type). Since the Rectangle<T> classes generated by instantiating the template Rectangle are formally independent of each other, it doesn't work that way. However you can make use of multiple inheritance here:

class Rectangle // not inheriting from any Area type
{
  // Area independent interface
};

template<typename T> class SpecificRectangle:
  public Rectangle,
  public Area<T>
{
  // Area dependent stuff
};

void foo(Rectangle&); // A function which works with generic rectangles

int main()
{
  SpecificRectangle<int> intrect;
  foo(intrect);

  SpecificRectangle<char> charrect;
  foo(charrect);
}

If it is important that your generic Rectangle is derived from a generic Area you can do the same trick with Area too:

class Area
{
  // generic Area interface
};

class Rectangle:
  public virtual Area // virtual because of "diamond inheritance"
{
  // generic rectangle interface
};

template<typename T> class SpecificArea:
  public virtual Area
{
  // specific implementation of Area for type T
};

template<typename T> class SpecificRectangle:
  public Rectangle, // maybe this should be virtual as well, in case the hierarchy is extended later
  public SpecificArea<T> // no virtual inheritance needed here
{
  // specific implementation of Rectangle for type T
};

Parsing JSON with Unix tools

Here is the answer for shell nerds using POSIX shell (with local) and egrep: JSON.sh, 4.7 KB.

This thing has plenty of test cases, so it should be correct. It is also pipeable. It is used in the package manager for bash, bpkg.

"Untrusted App Developer" message when installing enterprise iOS Application

In iOS 9.1 and lower, go to Settings - General - Profiles - tap on your Profile - tap on Trust button.

When to use SELECT ... FOR UPDATE?

The only portable way to achieve consistency between rooms and tags and making sure rooms are never returned after they had been deleted is locking them with SELECT FOR UPDATE.

However in some systems locking is a side effect of concurrency control, and you achieve the same results without specifying FOR UPDATE explicitly.


To solve this problem, Thread 1 should SELECT id FROM rooms FOR UPDATE, thereby preventing Thread 2 from deleting from rooms until Thread 1 is done. Is that correct?

This depends on the concurrency control your database system is using.

  • MyISAM in MySQL (and several other old systems) does lock the whole table for the duration of a query.

  • In SQL Server, SELECT queries place shared locks on the records / pages / tables they have examined, while DML queries place update locks (which later get promoted to exclusive or demoted to shared locks). Exclusive locks are incompatible with shared locks, so either SELECT or DELETE query will lock until another session commits.

  • In databases which use MVCC (like Oracle, PostgreSQL, MySQL with InnoDB), a DML query creates a copy of the record (in one or another way) and generally readers do not block writers and vice versa. For these databases, a SELECT FOR UPDATE would come handy: it would lock either SELECT or the DELETE query until another session commits, just as SQL Server does.

When should one use REPEATABLE_READ transaction isolation versus READ_COMMITTED with SELECT ... FOR UPDATE?

Generally, REPEATABLE READ does not forbid phantom rows (rows that appeared or disappeared in another transaction, rather than being modified)

  • In Oracle and earlier PostgreSQL versions, REPEATABLE READ is actually a synonym for SERIALIZABLE. Basically, this means that the transaction does not see changes made after it has started. So in this setup, the last Thread 1 query will return the room as if it has never been deleted (which may or may not be what you wanted). If you don't want to show the rooms after they have been deleted, you should lock the rows with SELECT FOR UPDATE

  • In InnoDB, REPEATABLE READ and SERIALIZABLE are different things: readers in SERIALIZABLE mode set next-key locks on the records they evaluate, effectively preventing the concurrent DML on them. So you don't need a SELECT FOR UPDATE in serializable mode, but do need them in REPEATABLE READ or READ COMMITED.

Note that the standard on isolation modes does prescribe that you don't see certain quirks in your queries but does not define how (with locking or with MVCC or otherwise).

When I say "you don't need SELECT FOR UPDATE" I really should have added "because of side effects of certain database engine implementation".

How can I use a batch file to write to a text file?

You can use echo, and redirect the output to a text file (see notes below):

rem Saved in D:\Temp\WriteText.bat
@echo off
echo This is a test> test.txt
echo 123>> test.txt
echo 245.67>> test.txt

Output:

D:\Temp>WriteText

D:\Temp>type test.txt
This is a test
123
245.67

D:\Temp>

Notes:

  • @echo off turns off printing of each command to the console
  • Unless you give it a specific path name, redirection with > or >> will write to the current directory (the directory the code is being run in).
  • The echo This is a test > test.txt uses one > to overwrite any file that already exists with new content.
  • The remaining echo statements use two >> characters to append to the text file (add to), instead of overwriting it.
  • The type test.txt simply types the file output to the command window.

Ordering issue with date values when creating pivot tables

If you want to use a column with 24/11/15 (for 24th November 2015) in your Pivot that will sort correctly, you can make sure it is properly formatted by doing the following - highlight the column, go to Data – Text to Columns – click Next twice, then select “Date” and use the default of DMY (or select as applicable to your data) and click ok

When you pivot now you should see it sorting properly as we have properly formatted that column to be a date field so Excel can work with it

Node.js – events js 72 throw er unhandled 'error' event

For what is worth, I got this error doing a clean install of nodejs and npm packages of my current linux-distribution I've installed meteor using

npm install metor

And got the above referenced error. After wasting some time, I found out I should have used meteor's way to update itself:

meteor update

This command output, among others, the message that meteor was severely outdated (over 2 years) and that it was going to install itself using:

curl https://install.meteor.com/ | sh

Which was probably the command I should have run in the first place.

So the solution might be to upgrade/update whatever nodejs package(js) you're using.

telnet to port 8089 correct command

I believe telnet 74.255.12.25 8089 . Why don't u try both

How to retry image pull in a kubernetes Pods?

$ kubectl replace --force -f <resource-file>

if all goes well, you should see something like:

<resource-type> <resource-name> deleted
<resource-type> <resource-name> replaced

details of this can be found in the Kubernetes documentation, "manage-deployment" and kubectl-cheatsheet pages at the time of writing.

'^M' character at end of lines

Fix line endings in vi by running the following:

:set fileformat=unix

:w

How to store array or multiple values in one column

You have a couple of questions here, so I'll address them separately:

I need to store a number of selected items in one field in a database

My general rule is: don't. This is something which all but requires a second table (or third) with a foreign key. Sure, it may seem easier now, but what if the use case comes along where you need to actually query for those items individually? It also means that you have more options for lazy instantiation and you have a more consistent experience across multiple frameworks/languages. Further, you are less likely to have connection timeout issues (30,000 characters is a lot).

You mentioned that you were thinking about using ENUM. Are these values fixed? Do you know them ahead of time? If so this would be my structure:

Base table (what you have now):

| id primary_key sequence
| -- other columns here.

Items table:

| id primary_key sequence
| descript VARCHAR(30) UNIQUE

Map table:

| base_id  bigint
| items_id bigint

Map table would have foreign keys so base_id maps to Base table, and items_id would map to the items table.

And if you'd like an easy way to retrieve this from a DB, then create a view which does the joins. You can even create insert and update rules so that you're practically only dealing with one table.

What format should I use store the data?

If you have to do something like this, why not just use a character delineated string? It will take less processing power than a CSV, XML, or JSON, and it will be shorter.

What column type should I use store the data?

Personally, I would use TEXT. It does not sound like you'd gain much by making this a BLOB, and TEXT, in my experience, is easier to read if you're using some form of IDE.

jquery : focus to div is not working

a <div> can be focused if it has a tabindex attribute. (the value can be set to -1)

For example:

$("#focus_point").attr("tabindex",-1).focus();

In addition, consider setting outline: none !important; so it displayed without a focus rectangle.

var element = $("#focus_point");
element.css('outline', 'none !important')
       .attr("tabindex", -1)
       .focus();

How do I implement charts in Bootstrap?

Later than my previous answer, but may be useful anyway; while gRaphaël Charting may be an outdated alternative, a more recent and nicer option may be http://chartjs.org - still without any Flash, with a MIT license, and a recently updated GitHub.

I've been using it myself since my last answer, so now I have some web apps with one and some with the other.

If you are starting a project anew, try with Chart.js first.

How to select a single field for all documents in a MongoDB collection?

For better understanding I have written similar MySQL query.

Selecting specific fields 

MongoDB : db.collection_name.find({},{name:true,email:true,phone:true});

MySQL : SELECT name,email,phone FROM table_name;

Selecting specific fields with where clause

MongoDB : db.collection_name.find({email:'[email protected]'},{name:true,email:true,phone:true});

MySQL : SELECT name,email,phone FROM table_name WHERE email = '[email protected]';

Highcharts - how to have a chart with dynamic height?

What if you hooked the window resize event:

$(window).resize(function() 
{    
    chart.setSize(
       $(document).width(), 
       $(document).height()/2,
       false
    );   
});

See example fiddle here.

Highcharts API Reference : setSize().

How to obtain the start time and end time of a day?

tl;dr

LocalDate                       // Represents an entire day, without time-of-day and without time zone.
.now(                           // Capture the current date.
    ZoneId.of( "Asia/Tokyo" )   // Returns a `ZoneId` object.
)                               // Returns a `LocalDate` object.
.atStartOfDay(                  // Determines the first moment of the day as seen on that date in that time zone. Not all days start at 00:00!
    ZoneId.of( "Asia/Tokyo" ) 
)                               // Returns a `ZonedDateTime` object.

Start of day

Get the full length of the today as seen in a time zone.

Using Half-Open approach, where the beginning is inclusive while the ending is exclusive. This approach solves the flaw in your code that fails to account for the very last second of the day.

ZoneId zoneId = ZoneId.of( "Africa/Tunis" ) ;
LocalDate today = LocalDate.now( zoneId  ) ;

ZonedDateTime zdtStart = today.atStartOfDay( zoneId ) ;
ZonedDateTime zdtStop = today.plusDays( 1 ).atStartOfDay( zoneId ) ;

zdtStart.toString() = 2020-01-30T00:00+01:00[Africa/Tunis]

zdtStop.toString() = 2020-01-31T00:00+01:00[Africa/Tunis]

See the same moments in UTC.

Instant start = zdtStart.toInstant() ;
Instant stop = zdtStop.toInstant() ;

start.toString() = 2020-01-29T23:00:00Z

stop.toString() = 2020-01-30T23:00:00Z

If you want the entire day of a date as seen in UTC rather than in a time zone, use OffsetDateTime.

LocalDate today = LocalDate.now( ZoneOffset.UTC  ) ;

OffsetDateTime odtStart = today.atTime( OffsetTime.MIN ) ;
OffsetDateTime odtStop = today.plusDays( 1 ).atTime( OffsetTime.MIN ) ;

odtStart.toString() = 2020-01-30T00:00+18:00

odtStop.toString() = 2020-01-31T00:00+18:00

These OffsetDateTime objects will already be in UTC, but you can call toInstant if you need such objects which are always in UTC by definition.

Instant start = odtStart.toInstant() ;
Instant stop = odtStop.toInstant() ;

start.toString() = 2020-01-29T06:00:00Z

stop.toString() = 2020-01-30T06:00:00Z

Tip: You may be interested in adding the ThreeTen-Extra library to your project to use its Interval class to represent this pair of Instant objects. This class offers useful methods for comparison such as abuts, overlaps, contains, and more.

Interval interval = Interval.of( start , stop ) ;

interval.toString() = 2020-01-29T06:00:00Z/2020-01-30T06:00:00Z

Half-Open

The answer by mprivat is correct. His point is to not try to obtain end of a day, but rather compare to "before start of next day". His idea is known as the "Half-Open" approach where a span of time has a beginning that is inclusive while the ending is exclusive.

  • The current date-time frameworks of Java (java.util.Date/Calendar and Joda-Time) both use milliseconds from the epoch. But in Java 8, the new JSR 310 java.time.* classes use nanoseconds resolution. Any code you wrote based on forcing the milliseconds count of last moment of day would be incorrect if switched to the new classes.
  • Comparing data from other sources becomes faulty if they employ other resolutions. For example, Unix libraries typically employ whole seconds, and databases such as Postgres resolve date-time to microseconds.
  • Some Daylight Saving Time changes happen over midnight which might further confuse things.

enter image description here

Joda-Time 2.3 offers a method for this very purpose, to obtain first moment of the day: withTimeAtStartOfDay(). Similarly in java.time, LocalDate::atStartOfDay.

Search StackOverflow for "joda half-open" to see more discussion and examples.

See this post, Time intervals and other ranges should be half-open, by Bill Schneider.

Avoid legacy date-time classes

The java.util.Date and .Calendar classes are notoriously troublesome. Avoid them.

Use java.time classes. The java.time framework is the official successor of the highly successful Joda-Time library.

java.time

The java.time framework is built into Java 8 and later. Back-ported to Java 6 & 7 in the ThreeTen-Backport project, further adapted to Android in the ThreeTenABP project.

An Instant is a moment on the timeline in UTC with a resolution of nanoseconds.

Instant instant = Instant.now();

Apply a time zone to get the wall-clock time for some locality.

ZoneId zoneId = ZoneId.of( "America/Montreal" );
ZonedDateTime zdt = ZonedDateTime.ofInstant( instant , zoneId );

To get the first moment of the day go through the LocalDate class and its atStartOfDay method.

ZonedDateTime zdtStart = zdt.toLocalDate().atStartOfDay( zoneId );

Using Half-Open approach, get first moment of following day.

ZonedDateTime zdtTomorrowStart = zdtStart.plusDays( 1 );

Table of all date-time types in Java, both modern and legacy

Currently the java.time framework lacks an Interval class as described below for Joda-Time. However, the ThreeTen-Extra project extends java.time with additional classes. This project is the proving ground for possible future additions to java.time. Among its classes is Interval. Construct an Interval by passing a pair of Instant objects. We can extract an Instant from our ZonedDateTime objects.

Interval today = Interval.of( zdtStart.toInstant() , zdtTomorrowStart.toInstant() );

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes. Hibernate 5 & JPA 2.2 support java.time.

Where to obtain the java.time classes?


Joda-Time

UPDATE: The Joda-Time project is now in maintenance-mode, and advises migration to the java.time classes. I am leaving this section intact for history.

Joda-Time has three classes to represent a span of time in various ways: Interval, Period, and Duration. An Interval has a specific beginning and ending on the timeline of the Universe. This fits our need to represent "a day".

We call the method withTimeAtStartOfDay rather than set time of day to zeros. Because of Daylight Saving Time and other anomalies the first moment of the day may not be 00:00:00.

Example code using Joda-Time 2.3.

DateTimeZone timeZone = DateTimeZone.forID( "America/Montreal" );
DateTime now = DateTime.now( timeZone );
DateTime todayStart = now.withTimeAtStartOfDay();
DateTime tomorrowStart = now.plusDays( 1 ).withTimeAtStartOfDay();
Interval today = new Interval( todayStart, tomorrowStart );

If you must, you can convert to a java.util.Date.

java.util.Date date = todayStart.toDate();

Select columns based on string match - dplyr::select

No need to use select just use [ instead

data[,grepl("search_string", colnames(data))]

Let's try with iris dataset

>iris[,grepl("Sepal", colnames(iris))]
  Sepal.Length Sepal.Width
1          5.1         3.5
2          4.9         3.0
3          4.7         3.2
4          4.6         3.1
5          5.0         3.6
6          5.4         3.9

@Value annotation type casting to Integer from String

Assuming you have a properties file on your classpath that contains

api.orders.pingFrequency=4

I tried inside a @Controller

@Controller
public class MyController {     
    @Value("${api.orders.pingFrequency}")
    private Integer pingFrequency;
    ...
}

With my servlet context containing :

<context:property-placeholder location="classpath:myprops.properties" />

It worked perfectly.

So either your property is not an integer type, you don't have the property placeholder configured correctly, or you are using the wrong property key.

I tried running with an invalid property value, 4123;. The exception I got is

java.lang.NumberFormatException: For input string: "4123;"

which makes me think the value of your property is

api.orders.pingFrequency=(java.lang.Integer)${api.orders.pingFrequency}

What is the difference between a mutable and immutable string in C#?

The data value may not be changed. Note: The variable value may be changed, but the original immutable data value was discarded and a new data value was created in memory.

Creating a blocking Queue<T> in .NET?

I haven't fully explored the TPL but they might have something that fits your needs, or at the very least, some Reflector fodder to snag some inspiration from.

Hope that helps.

Oracle: SQL query that returns rows with only numeric values

What about 1.1E10, +1, -0, etc? Parsing all possible numbers is trickier than many people think. If you want to include as many numbers are possible you should use the to_number function in a PL/SQL function. From http://www.oracle-developer.net/content/utilities/is_number.sql:

CREATE OR REPLACE FUNCTION is_number (str_in IN VARCHAR2) RETURN NUMBER IS
   n NUMBER;
BEGIN
   n := TO_NUMBER(str_in);
   RETURN 1;
EXCEPTION
   WHEN VALUE_ERROR THEN
      RETURN 0;
END;
/

Disable output buffering

# reopen stdout file descriptor with write mode
# and 0 as the buffer size (unbuffered)
import io, os, sys
try:
    # Python 3, open as binary, then wrap in a TextIOWrapper with write-through.
    sys.stdout = io.TextIOWrapper(open(sys.stdout.fileno(), 'wb', 0), write_through=True)
    # If flushing on newlines is sufficient, as of 3.7 you can instead just call:
    # sys.stdout.reconfigure(line_buffering=True)
except TypeError:
    # Python 2
    sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)

Credits: "Sebastian", somewhere on the Python mailing list.

Does this app use the Advertising Identifier (IDFA)? - AdMob 6.8.0

In app store connect now if we are using ads in our app then we will answer as yes to Does this app use the Advertising Identifier (IDFA)?

further 3 questions will be asked as

enter image description here

if your using just admob then check the first one and leave other two unchecked. Other two options (2nd , 3rd ) will be checked if your using app flyer to show ads. all options are explained with detail here

How do I add options to a DropDownList using jQuery?

With no plug-ins, this can be easier without using as much jQuery, instead going slightly more old-school:

var myOptions = {
    val1 : 'text1',
    val2 : 'text2'
};
$.each(myOptions, function(val, text) {
    $('#mySelect').append( new Option(text,val) );
});

If you want to specify whether or not the option a) is the default selected value, and b) should be selected now, you can pass in two more parameters:

    var defaultSelected = false;
    var nowSelected     = true;
    $('#mySelect').append( new Option(text,val,defaultSelected,nowSelected) );

ImportError: No module named model_selection

I had the same problem while using Jupyter Notebook, no matter what I updated in Python 3, conda, I could not get in Jupyter:

import sklearn
print (sklearn.__version__)
0.17.1

to SHOW scikit-learn-0.18.1

Finally, I removed Anaconda3 and Jupyter Notebook and reinstalled fresh. I got it to work.

http://ukitech.blogspot.com/2017/02/sklearnmodelselection.html

JavaScript: client-side vs. server-side validation

If you are doing light validation, it is best to do it on the client. It will save the network traffic which will help your server perform better. If if it complicated validation that involves pulling data from a database or something, like passwords, then it best to do it on the server where the data can be securely checked.

Convert Xml to DataTable

DataSet ds = new DataSet();
ds.ReadXml(fileNamePath);

CSS: background image on background color

The next syntax can be used as well.

background: <background-color> 
            url('../assets/icons/my-icon.svg')
            <background-position-x background-position-y>
            <background-repeat>;

It allows you combining background-color, background-image, background-position and background-repeat properties.

Example

background: #696969 url('../assets/icons/my-icon.svg') center center no-repeat;

jQuery: print_r() display equivalent?

You could use very easily reflection to list all properties, methods and values.

For Gecko based browsers you can use the .toSource() method:

var data = new Object();
data["firstname"] = "John";
data["lastname"] = "Smith";
data["age"] = 21;

alert(data.toSource()); //Will return "({firstname:"John", lastname:"Smith", age:21})"

But since you use Firebug, why not just use console.log?

JQuery addclass to selected div, remove class if another div is selected

I had to transform the divs to list items otherwise all my divs would get that class and only the generated ones should get it Thanks everyone, I love this site and the helpful people on it !!!! You can follow the newbie school project at http://low-budgetwebservice.be/project/webbuilder.html suggestions are always welcome :). So this worked for me:

            /* Add Class Heading*/
            $(document).ready(function() {
            $( document ).on( 'click', 'ul#items li', function () { 
            $('ul#items li').removeClass('active'); 
            $(this).addClass('active');
            });
            });

how to set value of a input hidden field through javascript?

Your code for setting value for hidden input is correct. Here is the example. Maybe you have some conditions in your if statements that are not allowing your scripts to execute.

How to take MySQL database backup using MySQL Workbench?

The Data Export function in MySQL Workbench allows 2 of the 3 ways. There's a checkbox Skip Table Data (no-data) on the export page which allows to either dump with or without data. Just dumping the data without meta data is not supported.

Using pg_dump to only get insert statements from one table within database

if version < 8.4.0

pg_dump -D -t <table> <database>

Add -a before the -t if you only want the INSERTs, without the CREATE TABLE etc to set up the table in the first place.

version >= 8.4.0

pg_dump --column-inserts --data-only --table=<table> <database>

post checkbox value

You should use

<input type="submit" value="submit" />

inside your form.

and add action into your form tag for example:

<form action="booking.php" method="post">

It's post your form into action which you choose.

From php you can get this value by

$_POST['booking-check'];

How to use Utilities.sleep() function

Utilities.sleep(milliseconds) creates a 'pause' in program execution, meaning it does nothing during the number of milliseconds you ask. It surely slows down your whole process and you shouldn't use it between function calls. There are a few exceptions though, at least that one that I know : in SpreadsheetApp when you want to remove a number of sheets you can add a few hundreds of millisecs between each deletion to allow for normal script execution (but this is a workaround for a known issue with this specific method). I did have to use it also when creating many sheets in a spreadsheet to avoid the Browser needing to be 'refreshed' after execution.

Here is an example :

function delsheets(){
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var numbofsheet=ss.getNumSheets();// check how many sheets in the spreadsheet
  for (pa=numbofsheet-1;pa>0;--pa){ 
    ss.setActiveSheet(ss.getSheets()[pa]);
    var newSheet = ss.deleteActiveSheet(); // delete sheets begining with the last one
    Utilities.sleep(200);// pause in the loop for 200 milliseconds
  }
  ss.setActiveSheet(ss.getSheets()[0]);// return to first sheet as active sheet (useful in 'list' function)
}

What does `unsigned` in MySQL mean and when to use it?

MySQL says:

All integer types can have an optional (nonstandard) attribute UNSIGNED. Unsigned type can be used to permit only nonnegative numbers in a column or when you need a larger upper numeric range for the column. For example, if an INT column is UNSIGNED, the size of the column's range is the same but its endpoints shift from -2147483648 and 2147483647 up to 0 and 4294967295.

When do I use it ?

Ask yourself this question: Will this field ever contain a negative value?
If the answer is no, then you want an UNSIGNED data type.

A common mistake is to use a primary key that is an auto-increment INT starting at zero, yet the type is SIGNED, in that case you’ll never touch any of the negative numbers and you are reducing the range of possible id's to half.

jQuery serialize does not register checkboxes

Try this:

$(':input[type="checkbox"]:checked').map(function(){return this.value}).get();

How do you wait for input on the same Console.WriteLine() line?

Use Console.Write instead, so there's no newline written:

Console.Write("What is your name? ");
var name = Console.ReadLine();

Best way to incorporate Volley (or other library) into Android Studio project

UPDATE:

compile 'com.android.volley:volley:1.0.0'

OLD ANSWER: You need the next in your build.gradle of your app module:

dependencies {
        compile 'com.mcxiaoke.volley:library:1.0.19'
        (Rest of your dependencies)

    }

This is not the official repo but is a highly trusted one.

Python, TypeError: unhashable type: 'list'

The problem is that you can't use a list as the key in a dict, since dict keys need to be immutable. Use a tuple instead.

This is a list:

[x, y]

This is a tuple:

(x, y)

Note that in most cases, the ( and ) are optional, since , is what actually defines a tuple (as long as it's not surrounded by [] or {}, or used as a function argument).

You might find the section on tuples in the Python tutorial useful:

Though tuples may seem similar to lists, they are often used in different situations and for different purposes. Tuples are immutable, and usually contain an heterogeneous sequence of elements that are accessed via unpacking (see later in this section) or indexing (or even by attribute in the case of namedtuples). Lists are mutable, and their elements are usually homogeneous and are accessed by iterating over the list.

And in the section on dictionaries:

Unlike sequences, which are indexed by a range of numbers, dictionaries are indexed by keys, which can be any immutable type; strings and numbers can always be keys. Tuples can be used as keys if they contain only strings, numbers, or tuples; if a tuple contains any mutable object either directly or indirectly, it cannot be used as a key. You can’t use lists as keys, since lists can be modified in place using index assignments, slice assignments, or methods like append() and extend().


In case you're wondering what the error message means, it's complaining because there's no built-in hash function for lists (by design), and dictionaries are implemented as hash tables.

MS Access - execute a saved query by name in VBA

You should investigate why VBA can't find queryname.

I have a saved query named qryAddLoginfoRow. It inserts a row with the current time into my loginfo table. That query runs successfully when called by name by CurrentDb.Execute.

CurrentDb.Execute "qryAddLoginfoRow"

My guess is that either queryname is a variable holding the name of a query which doesn't exist in the current database's QueryDefs collection, or queryname is the literal name of an existing query but you didn't enclose it in quotes.

Edit: You need to find a way to accept that queryname does not exist in the current db's QueryDefs collection. Add these 2 lines to your VBA code just before the CurrentDb.Execute line.

Debug.Print "queryname = '" & queryname & "'"
Debug.Print CurrentDb.QueryDefs(queryname).Name

The second of those 2 lines will trigger run-time error 3265, "Item not found in this collection." Then go to the Immediate window to verify the name of the query you're asking CurrentDb to Execute.

Which command in VBA can count the number of characters in a string variable?

Do you mean counting the number of characters in a string? That's very simple

Dim strWord As String
Dim lngNumberOfCharacters as Long

strWord = "habit"
lngNumberOfCharacters = Len(strWord)
Debug.Print lngNumberOfCharacters

How do I replace part of a string in PHP?

You can try

$string = "this is the test for string." ;
$string = str_replace(' ', '_', $string);
$string = substr($string,0,10);

var_dump($string);

Output

this_is_th

package android.support.v4.app does not exist ; in Android studio 0.8

In my case the problem was solved by appending the string cordova.system.library.2=com.android.support:support-v4:+ to platforms/android/project.properties file

What key in windows registry disables IE connection parameter "Automatically Detect Settings"?

I can confirm this works. I exported the reg file after I had made the adjustments and then put it in a logon script like this:

REM ------ IE Auto Detect Settings FIX ------------------
REG IMPORT \\mydomain.local\netlogon\IE-Autofix.reg 2>NUL

How does HttpContext.Current.User.Identity.Name know which usernames exist?

The HttpContext.Current.User.Identity.Name returns null

This depends on whether the authentication mode is set to Forms or Windows in your web.config file.

For example, if I write the authentication like this:

<authentication mode="Forms"/>

Then because the authentication mode="Forms", I will get null for the username. But if I change the authentication mode to Windows like this:

<authentication mode="Windows"/>

I can run the application again and check for the username, and I will get the username successfully.

For more information, see System.Web.HttpContext.Current.User.Identity.Name Vs System.Environment.UserName in ASP.NET.

Javascript: Fetch DELETE and PUT requests

Here is a fetch POST example. You can do the same for DELETE.

function createNewProfile(profile) {
    const formData = new FormData();
    formData.append('first_name', profile.firstName);
    formData.append('last_name', profile.lastName);
    formData.append('email', profile.email);

    return fetch('http://example.com/api/v1/registration', {
        method: 'POST',
        body: formData
    }).then(response => response.json())
}

createNewProfile(profile)
   .then((json) => {
       // handle success
    })
   .catch(error => error);

How do you detect/avoid Memory leaks in your (Unmanaged) code?

Paul Nettle's mmgr is a long time favourite tool of mine. You include mmgr.h in your source files, define TEST_MEMORY, and it delivers a textfile full of memory problems that occurred during a run of your app.

How to put the legend out of the plot

There are a number of ways to do what you want. To add to what @inalis and @Navi already said, you can use the bbox_to_anchor keyword argument to place the legend partially outside the axes and/or decrease the font size.

Before you consider decreasing the font size (which can make things awfully hard to read), try playing around with placing the legend in different places:

So, let's start with a generic example:

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
    ax.plot(x, i * x, label='$y = %ix$' % i)

ax.legend()

plt.show()

alt text

If we do the same thing, but use the bbox_to_anchor keyword argument we can shift the legend slightly outside the axes boundaries:

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
    ax.plot(x, i * x, label='$y = %ix$' % i)
 
ax.legend(bbox_to_anchor=(1.1, 1.05))

plt.show()

alt text

Similarly, make the legend more horizontal and/or put it at the top of the figure (I'm also turning on rounded corners and a simple drop shadow):

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
    line, = ax.plot(x, i * x, label='$y = %ix$'%i)

ax.legend(loc='upper center', bbox_to_anchor=(0.5, 1.05),
          ncol=3, fancybox=True, shadow=True)
plt.show()

alt text

Alternatively, shrink the current plot's width, and put the legend entirely outside the axis of the figure (note: if you use tight_layout(), then leave out ax.set_position():

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
    ax.plot(x, i * x, label='$y = %ix$'%i)

# Shrink current axis by 20%
box = ax.get_position()
ax.set_position([box.x0, box.y0, box.width * 0.8, box.height])

# Put a legend to the right of the current axis
ax.legend(loc='center left', bbox_to_anchor=(1, 0.5))

plt.show()

alt text

And in a similar manner, shrink the plot vertically, and put a horizontal legend at the bottom:

import matplotlib.pyplot as plt
import numpy as np

x = np.arange(10)

fig = plt.figure()
ax = plt.subplot(111)

for i in xrange(5):
    line, = ax.plot(x, i * x, label='$y = %ix$'%i)

# Shrink current axis's height by 10% on the bottom
box = ax.get_position()
ax.set_position([box.x0, box.y0 + box.height * 0.1,
                 box.width, box.height * 0.9])

# Put a legend below current axis
ax.legend(loc='upper center', bbox_to_anchor=(0.5, -0.05),
          fancybox=True, shadow=True, ncol=5)

plt.show()

alt text

Have a look at the matplotlib legend guide. You might also take a look at plt.figlegend().

React Native fetch() Network Request Failed

in my case i have https url but fetch return Network Request Failed error so i just stringify the body and it s working fun

_x000D_
_x000D_
fetch('https://mywebsite.com/endpoint/', {
  method: 'POST',
  headers: {
    Accept: 'application/json',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    firstParam: 'yourValue',
    secondParam: 'yourOtherValue'
  })
});
_x000D_
_x000D_
_x000D_

Displaying unicode symbols in HTML

You should ensure the HTTP server headers are correct.

In particular, the header:

Content-Type: text/html; charset=utf-8

should be present.

The meta tag is ignored by browsers if the HTTP header is present.

Also ensure that your file is actually encoded as UTF-8 before serving it, check/try the following:

  • Ensure your editor save it as UTF-8.
  • Ensure your FTP or any file transfer program does not mess with the file.
  • Try with HTML encoded entities, like &#uuu;.
  • To be really sure, hexdump the file and look as the character, for the ?, it should be E2 9C 94 .

Note: If you use an unicode character for which your system can't find a glyph (no font with that character), your browser should display a question mark or some block like symbol. But if you see multiple roman characters like you do, this denotes an encoding problem.

React native ERROR Packager can't listen on port 8081

First of all, in your device go to Dev. Option -> ADB over Network after do it:

$ adb connect <your device adb network>
$ react-native run-android 

(or run-ios, by the way)

if this has successfully your device has installed app-debug.apk, open app-debug and go to Dev. Settings -> Debug server host & port for device, type in your machine's IP address (generally, System preference -> Network), as in the example below < your machine's IP address >:8081 (whihout inequality)

finally, execute the command below

$ react-native start --port=8081

try another ports, and verify that you machine and your device are same network.

How to remove a newline from a string in Bash

To address one possible root of the actual issue, there is a chance you are sourcing a crlf file.

CRLF Example:

.env (crlf)

VARIABLE_A="abc"
VARIABLE_B="def"

run.sh

#!/bin/bash
source .env
echo "$VARIABLE_A"
echo "$VARIABLE_B"
echo "$VARIABLE_A $VARIABLE_B"

Returns:

abc
def
 def

If however you convert to LF:

.env (lf)

VARIABLE_A="abc"
VARIABLE_B="def"

run.sh

#!/bin/bash
source .env
echo "$VARIABLE_A"
echo "$VARIABLE_B"
echo "$VARIABLE_A $VARIABLE_B"

Returns:

abc
def
abc def

Date format Mapping to JSON Jackson

Since Jackson v2.0, you can use @JsonFormat annotation directly on Object members;

@JsonFormat(shape = JsonFormat.Shape.STRING, pattern = "yyyy-MM-dd HH:mm a z")
private Date date;

Display help message with python argparse when script is called without any arguments

If you have arguments that must be specified for the script to run - use the required parameter for ArgumentParser as shown below:-

parser.add_argument('--foo', required=True)

parse_args() will report an error if the script is run without any arguments.

How to make a PHP SOAP call using the SoapClient class

You need declare class Contract

class Contract {
  public $id;
  public $name;
}

$contract = new Contract();
$contract->id = 100;
$contract->name = "John";

$params = array(
  "Contact" => $contract,
  "description" => "Barrel of Oil",
  "amount" => 500,
);

or

$params = array(
  $contract,
  "description" => "Barrel of Oil",
  "amount" => 500,
);

Then

$response = $client->__soapCall("Function1", array("FirstFunction" => $params));

or

$response = $client->__soapCall("Function1", $params);

How to make a back-to-top button using CSS and HTML only?

Hope this helps somebody!

<style> html { scroll-behavior: smooth;} </style>
<a id="top"></>
<!--content here-->
<a href="#top">Back to top..</a>

How do I find the parent directory in C#?

I've found variants of System.IO.Path.Combine(myPath, "..") to be the easiest and most reliable. Even more so if what northben says is true, that GetParent requires an extra call if there is a trailing slash. That, to me, is unreliable.

Path.Combine makes sure you never go wrong with slashes.

.. behaves exactly like it does everywhere else in Windows. You can add any number of \.. to a path in cmd or explorer and it will behave exactly as I describe below.

Some basic .. behavior:

  1. If there is a file name, .. will chop that off:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..") => D:\Grandparent\Parent\

  1. If the path is a directory, .. will move up a level:

Path.Combine(@"D:\Grandparent\Parent\", "..") => D:\Grandparent\

  1. ..\.. follows the same rules, twice in a row:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", @"..\..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", @"..\..") => D:\

  1. And this has the exact same effect:

Path.Combine(@"D:\Grandparent\Parent\Child.txt", "..", "..") => D:\Grandparent\ Path.Combine(@"D:\Grandparent\Parent\", "..", "..") => D:\

Why use the 'ref' keyword when passing an object?

In .NET when you pass any parameter to a method, a copy is created. In value types means that any modification you make to the value is at the method scope, and is lost when you exit the method.

When passing a Reference Type, a copy is also made, but it is a copy of a reference, i.e. now you have TWO references in memory to the same object. So, if you use the reference to modify the object, it gets modified. But if you modify the reference itself - we must remember it is a copy - then any changes are also lost upon exiting the method.

As people have said before, an assignment is a modification of the reference, thus is lost:

public void Method1(object obj) {   
 obj = new Object(); 
}

public void Method2(object obj) {  
 obj = _privateObject; 
}

The methods above does not modifies the original object.

A little modification of your example

 using System;

    class Program
        {
            static void Main(string[] args)
            {
                TestRef t = new TestRef();
                t.Something = "Foo";

                DoSomething(t);
                Console.WriteLine(t.Something);

            }

            static public void DoSomething(TestRef t)
            {
                t = new TestRef();
                t.Something = "Bar";
            }
        }



    public class TestRef
    {
    private string s;
        public string Something 
        { 
            get {return s;} 
            set { s = value; }
        }
    }

C# list.Orderby descending

list = new List<ProcedureTime>(); sortedList = list.OrderByDescending(ProcedureTime=> ProcedureTime.EndTime).ToList();

Which works for me to show the time sorted in descending order.

Selecting rows where remainder (modulo) is 1 after division by 2?

At least some versions of SQL (Oracle, Informix, DB2, ISO Standard) support:

WHERE MOD(value, 2) = 1

MySQL supports '%' as the modulus operator:

WHERE value % 2 = 1

How to pass props to {this.props.children}

Passing Props to Nested Children

With the update to React 16.6 you can now use React.createContext and contextType.

import * as React from 'react';

// React.createContext accepts a defaultValue as the first param
const MyContext = React.createContext(); 

class Parent extends React.Component {
  doSomething = (value) => {
    // Do something here with value
  };

  render() {
    return (
       <MyContext.Provider value={{ doSomething: this.doSomething }}>
         {this.props.children}
       </MyContext.Provider>
    );
  }
}

class Child extends React.Component {
  static contextType = MyContext;

  onClick = () => {
    this.context.doSomething(this.props.value);
  };      

  render() {
    return (
      <div onClick={this.onClick}>{this.props.value}</div>
    );
  }
}


// Example of using Parent and Child

import * as React from 'react';

class SomeComponent extends React.Component {

  render() {
    return (
      <Parent>
        <Child value={1} />
        <Child value={2} />
      </Parent>
    );
  }
}

React.createContext shines where React.cloneElement case couldn't handle nested components

class SomeComponent extends React.Component {

  render() {
    return (
      <Parent>
        <Child value={1} />
        <SomeOtherComp><Child value={2} /></SomeOtherComp>
      </Parent>
    );
  }
}

Dynamically access object property using variable

It gets interesting when you have to pass parameters to this function as well.

Code jsfiddle

var obj = {method:function(p1,p2,p3){console.log("method:",arguments)}}

var str = "method('p1', 'p2', 'p3');"

var match = str.match(/^\s*(\S+)\((.*)\);\s*$/);

var func = match[1]
var parameters = match[2].split(',');
for(var i = 0; i < parameters.length; ++i) {
  // clean up param begninning
    parameters[i] = parameters[i].replace(/^\s*['"]?/,'');
  // clean up param end
  parameters[i] = parameters[i].replace(/['"]?\s*$/,'');
}

obj[func](parameters); // sends parameters as array
obj[func].apply(this, parameters); // sends parameters as individual values

How to add border around linear layout except at the bottom?

Create an XML file named border.xml in the drawable folder and put the following code in it.

 <?xml version="1.0" encoding="utf-8"?>
 <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
  <item> 
    <shape android:shape="rectangle">
      <solid android:color="#FF0000" /> 
    </shape>
  </item>   
    <item android:left="5dp" android:right="5dp"  android:top="5dp" >  
     <shape android:shape="rectangle"> 
      <solid android:color="#000000" />
    </shape>
   </item>    
 </layer-list> 

Then add a background to your linear layout like this:

         android:background="@drawable/border"

EDIT :

This XML was tested with a galaxy s running GingerBread 2.3.3 and ran perfectly as shown in image below:

enter image description here

ALSO

tested with galaxy s 3 running JellyBean 4.1.2 and ran perfectly as shown in image below :

enter image description here

Finally its works perfectly with all APIs

EDIT 2 :

It can also be done using a stroke to keep the background as transparent while still keeping a border except at the bottom with the following code.

<?xml version="1.0" encoding="utf-8"?>
 <layer-list xmlns:android="http://schemas.android.com/apk/res/android">
   <item android:left="0dp" android:right="0dp"  android:top="0dp"  
        android:bottom="-10dp"> 
    <shape android:shape="rectangle">
     <stroke android:width="10dp" android:color="#B22222" />
    </shape>
   </item>  
 </layer-list> 

hope this help .

How to display Base64 images in HTML?

put base64()

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<img src="data:image/png;base64,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"></img>
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in Javascript

var id=document.getElementById("image");

id.src=base64Url;

Android SDK Manager Not Installing Components

Try running Android Studio as an administrator, by right-clicking on the .exe and selecting "Run As Administrator".

Also, some anti-virus programs have been known to interfere with SDK Manager.

Detect if Android device has Internet connection

You don't necessarily need to make a full HTTP connection. You could try just opening a TCP connection to a known host and if it succeeds you have internet connectivity.

public boolean hostAvailable(String host, int port) {
  try (Socket socket = new Socket()) {
    socket.connect(new InetSocketAddress(host, port), 2000);
    return true;
  } catch (IOException e) {
    // Either we have a timeout or unreachable host or failed DNS lookup
    System.out.println(e);
    return false;
  }
}

Then just check with:

boolean online = hostAvailable("www.google.com", 80);

Change a column type from Date to DateTime during ROR migration

AFAIK, migrations are there to try to reshape data you care about (i.e. production) when making schema changes. So unless that's wrong, and since he did say he does not care about the data, why not just modify the column type in the original migration from date to datetime and re-run the migration? (Hope you've got tests:)).

Java 8 forEach with index

There are workarounds but no clean/short/sweet way to do it with streams and to be honest, you would probably be better off with:

int idx = 0;
for (Param p : params) query.bind(idx++, p);

Or the older style:

for (int idx = 0; idx < params.size(); idx++) query.bind(idx, params.get(idx));

C multi-line macro: do/while(0) vs scope block

Andrey Tarasevich provides the following explanation:

  1. On Google Groups
  2. On bytes.com

[Minor changes to formatting made. Parenthetical annotations added in square brackets []].

The whole idea of using 'do/while' version is to make a macro which will expand into a regular statement, not into a compound statement. This is done in order to make the use of function-style macros uniform with the use of ordinary functions in all contexts.

Consider the following code sketch:

if (<condition>)
  foo(a);
else
  bar(a);

where foo and bar are ordinary functions. Now imagine that you'd like to replace function foo with a macro of the above nature [named CALL_FUNCS]:

if (<condition>)
  CALL_FUNCS(a);
else
  bar(a);

Now, if your macro is defined in accordance with the second approach (just { and }) the code will no longer compile, because the 'true' branch of if is now represented by a compound statement. And when you put a ; after this compound statement, you finished the whole if statement, thus orphaning the else branch (hence the compilation error).

One way to correct this problem is to remember not to put ; after macro "invocations":

if (<condition>)
  CALL_FUNCS(a)
else
  bar(a);

This will compile and work as expected, but this is not uniform. The more elegant solution is to make sure that macro expand into a regular statement, not into a compound one. One way to achieve that is to define the macro as follows:

#define CALL_FUNCS(x) \
do { \
  func1(x); \
  func2(x); \
  func3(x); \
} while (0)

Now this code:

if (<condition>)
  CALL_FUNCS(a);
else
  bar(a);

will compile without any problems.

However, note the small but important difference between my definition of CALL_FUNCS and the first version in your message. I didn't put a ; after } while (0). Putting a ; at the end of that definition would immediately defeat the entire point of using 'do/while' and make that macro pretty much equivalent to the compound-statement version.

I don't know why the author of the code you quoted in your original message put this ; after while (0). In this form both variants are equivalent. The whole idea behind using 'do/while' version is not to include this final ; into the macro (for the reasons that I explained above).

MS-DOS Batch file pause with enter key

pause command is what you looking for. If you looking ONLY the case when enter is hit you can abuse the runas command:

runas /user:# "" >nul 2>&1

the screen will be frozen until enter is hit.What I like more than set/p= is that if you press other buttons than enter they will be not displayed.

When should an IllegalArgumentException be thrown?

When talking about "bad input", you should consider where the input is coming from.

Is the input entered by a user or another external system you don't control, you should expect the input to be invalid, and always validate it. It's perfectly ok to throw a checked exception in this case. Your application should 'recover' from this exception by providing an error message to the user.

If the input originates from your own system, e.g. your database, or some other parts of your application, you should be able to rely on it to be valid (it should have been validated before it got there). In this case it's perfectly ok to throw an unchecked exception like an IllegalArgumentException, which should not be caught (in general you should never catch unchecked exceptions). It is a programmer's error that the invalid value got there in the first place ;) You need to fix it.

Cannot install signed apk to device manually, got error "App not installed"

minifyEnabled false

is the only that worked for me after 3 days of research on all forum!

Change header text of columns in a GridView

protected void grdDis_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            #region Dynamically Show gridView header From data base
            getAllheaderName();/*To get all Allowences master headerName*/

            TextBox txt_Days = (TextBox)grdDis.HeaderRow.FindControl("txtDays");
            txt_Days.Text = hidMonthsDays.Value;
            #endregion
        }
    }

Copy Files from Windows to the Ubuntu Subsystem

You should only access Linux files system (those located in lxss folder) from inside WSL; DO NOT create/modify any files in lxss folder in Windows - it's dangerous and WSL will not see these files.

Files can be shared between WSL and Windows, though; put the file outside of lxss folder. You can access them via drvFS (/mnt) such as /mnt/c/Users/yourusername/files within WSL. These files stay synced between WSL and Windows.

For details and why, see: https://blogs.msdn.microsoft.com/commandline/2016/11/17/do-not-change-linux-files-using-windows-apps-and-tools/

How to dynamic filter options of <select > with jQuery?

I had a similar problem to this, so I altered the accepted answer to make a more generic version of the function. I thought I'd leave it here.

var filterSelectOptions = function($select, callback) {

    var options = null,
        dataOptions = $select.data('options');

    if (typeof dataOptions === 'undefined') {
        options = [];
        $select.children('option').each(function() {
            var $this = $(this);
            options.push({value: $this.val(), text: $this.text()});
        });
        $select.data('options', options);
    } else {
        options = dataOptions;
    }

    $select.empty();

    $.each(options, function(i) {
        var option = options[i];
        if(callback(option)) {
            $select.append(
                $('<option/>').text(option.text).val(option.value)
            );
        }
    });
};

Difference between IsNullOrEmpty and IsNullOrWhiteSpace in C#

String.IsNullOrEmpty(string value) returns true if the string is null or empty. For reference an empty string is represented by "" (two double quote characters)

String.IsNullOrWhitespace(string value) returns true if the string is null, empty, or contains only whitespace characters such as a space or tab.

To see what characters count as whitespace consult this link: http://msdn.microsoft.com/en-us/library/t809ektx.aspx

CSS: fixed position on x-axis but not y?

Updated the script to check the start position:

function float_horizontal_scroll(id) {
var el = jQuery(id);
var isLeft = el.css('left') !== 'auto';
var start =((isLeft ? el.css('left') : el.css('right')).replace("px", ""));
jQuery(window).scroll(function () {
    var leftScroll = jQuery(this).scrollLeft();
    if (isLeft)
        el.css({ 'left': (start + leftScroll) + 'px' });
    else
        el.css({ 'right': (start - leftScroll) + 'px' });
});

}

how to insert a new line character in a string to PrintStream then use a scanner to re-read the file

The linefeed character \n is not the line separator in certain operating systems (such as windows, where it's "\r\n") - my suggestion is that you use \r\n instead, then it'll both see the line-break with only \n and \r\n, I've never had any problems using it.

Also, you should look into using a StringBuilder instead of concatenating the String in the while-loop at BookCatalog.toString(), it is a lot more effective. For instance:

public String toString() {
        BookNode current = front;
        StringBuilder sb = new StringBuilder();
        while (current!=null){
            sb.append(current.getData().toString()+"\r\n ");
            current = current.getNext();
        }
        return sb.toString();
}

How can I implement custom Action Bar with custom buttons in Android?

1 You can use a drawable

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item android:id="@+id/menu_item1"
        android:icon="@drawable/my_item_drawable"
        android:title="@string/menu_item1"
        android:showAsAction="ifRoom" />
</menu>

2 Create a style for the action bar and use a custom background:

<resources>
    <!-- the theme applied to the application or activity -->
    <style name="CustomActivityTheme" parent="@android:style/Theme.Holo">
        <item name="android:actionBarStyle">@style/MyActionBar</item>
        <!-- other activity and action bar styles here -->
    </style>
    <!-- style for the action bar backgrounds -->
    <style name="MyActionBar" parent="@android:style/Widget.Holo.ActionBar">
        <item name="android:background">@drawable/background</item>
        <item name="android:backgroundStacked">@drawable/background</item>
        <item name="android:backgroundSplit">@drawable/split_background</item>
    </style>
</resources>

3 Style again android:actionBarDivider

The android documentation is very usefull for that.

What is the difference between visibility:hidden and display:none?

They are not synonyms.

display:none removes the element from the normal flow of the page, allowing other elements to fill in.

visibility:hidden leaves the element in the normal flow of the page such that is still occupies space.

Imagine you are in line for a ride at an amusement park and someone in the line gets so rowdy that security plucks them from the line. Everyone in line will then move forward one position to fill the now empty slot. This is like display:none.

Contrast this with the similar situation, but that someone in front of you puts on an invisibility cloak. While viewing the line, it will look like there is an empty space, but people can't really fill that empty looking space because someone is still there. This is like visibility:hidden.

Get encoding of a file in Windows

Here's my take how to detect the Unicode family of text encodings via BOM. The accuracy of this method is low, as this method only works on text files (specifically Unicode files), and defaults to ascii when no BOM is present (like most text editors, the default would be UTF8 if you want to match the HTTP/web ecosystem).

Update 2018: I no longer recommend this method. I recommend using file.exe from GIT or *nix tools as recommended by @Sybren, and I show how to do that via PowerShell in a later answer.

# from https://gist.github.com/zommarin/1480974
function Get-FileEncoding($Path) {
    $bytes = [byte[]](Get-Content $Path -Encoding byte -ReadCount 4 -TotalCount 4)

    if(!$bytes) { return 'utf8' }

    switch -regex ('{0:x2}{1:x2}{2:x2}{3:x2}' -f $bytes[0],$bytes[1],$bytes[2],$bytes[3]) {
        '^efbbbf'   { return 'utf8' }
        '^2b2f76'   { return 'utf7' }
        '^fffe'     { return 'unicode' }
        '^feff'     { return 'bigendianunicode' }
        '^0000feff' { return 'utf32' }
        default     { return 'ascii' }
    }
}

dir ~\Documents\WindowsPowershell -File | 
    select Name,@{Name='Encoding';Expression={Get-FileEncoding $_.FullName}} | 
    ft -AutoSize

Recommendation: This can work reasonably well if the dir, ls, or Get-ChildItem only checks known text files, and when you're only looking for "bad encodings" from a known list of tools. (i.e. SQL Management Studio defaults to UTF16, which broke GIT auto-cr-lf for Windows, which was the default for many years.)

How to read a file without newlines?

another example:

Reading file one row at the time. Removing unwanted chars with from end of the string str.rstrip(chars)

with open(filename, 'r') as fileobj:
    for row in fileobj:
        print( row.rstrip('\n') )

see also str.strip([chars]) and str.lstrip([chars])

(python >= 2.0)

How can you debug a CORS request with cURL?

Seems like just this works:

curl -I http://example.com

Look for Access-Control-Allow-Origin: * in the returned headers

How do I concatenate or merge arrays in Swift?

To complete the list of possible alternatives, reduce could be used to implement the behavior of flatten:

var a = ["a", "b", "c"] 
var b = ["d", "e", "f"]

let res = [a, b].reduce([],combine:+)

The best alternative (performance/memory-wise) among the ones presented is simply flatten, that just wrap the original arrays lazily without creating a new array structure.

But notice that flatten does not return a LazyCollection, so that lazy behavior will not be propagated to the next operation along the chain (map, flatMap, filter, etc...).

If lazyness makes sense in your particular case, just remember to prepend or append a .lazy to flatten(), for example, modifying Tomasz sample this way:

let c = [a, b].lazy.flatten()

How to deploy a React App on Apache web server

As well described in React's official docs, If you use routers that use the HTML5 pushState history API under the hood, you just need to below content to .htaccess file in public directory of your react-app.

Options -MultiViews
    RewriteEngine On
    RewriteCond %{REQUEST_FILENAME} !-f
    RewriteRule ^ index.html [QSA,L]

And if using relative path update the package.json like this:

"homepage": ".",

Note: If you are using react-router@^4, you can root <Link> using the basename prop on any <Router>.

import React from 'react';
import BrowserRouter as Router from 'react-router-dom';
...
<Router basename="/calendar"/>
<Link to="/today"/>

Sending private messages to user

If you want to send the message to a predetermined person, such as yourself, you can set it so that the channel it would be messaging to would be their (your) own userID. So for instance, if you're using the discord bot tutorials from Digital Trends, where it says "to: ", you would continue with their (or your) userID. For instance, with how that specific code is set up, you could do "to: userID", and it would message that person. Or, if you want the bot to message you any time someone uses a specific command, you could do "to: '12345678890'", the numbers being a filler for the actual userID. Hope this helps!

batch script - run command on each file in directory

you can run something like this (paste the code bellow in a .bat, or if you want it to run interractively replace the %% by % :

for %%i in (c:\directory\*.xls) do ssconvert %%i %%i.xlsx

If you can run powershell it will be :

Get-ChildItem -Path c:\directory -filter *.xls | foreach {ssconvert $($_.FullName) $($_.baseName).xlsx }

Examples of GoF Design Patterns in Java's core libraries

Even though I'm sort of a broken clock with this one, Java XML API uses Factory a lot. I mean just look at this:

Document doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(source);
String title = XPathFactory.newInstance().newXPath().evaluate("//title", doc);

...and so on and so forth.

Additionally various Buffers (StringBuffer, ByteBuffer, StringBuilder) use Builder.

How to check if the string is empty?

Below is a simple method to identify an empty string:

a="" #Empty string
if(len(a)==0): #len() is used to find the length of the string or variable inside its' brackets.
   print("Empty")
else:
   print("Filled")

The above len() method is an inbuilt function that helps us to find the length of a certain string or variable. It can also be used in the case of lists.

LOGIC: If the length of the character or variable is 0 then absolutely it means that the string or variable is empty. BUT remember that this will work only in the case of strings and lists and not with integers. Below is the code to find length of integers.

a=int(input())
if(len(str(a))==0):
   print(True)

In the above code str() is used to convert an int to a string format like from 123 to its string format "123". In the string format it will be valid.

How do I pass JavaScript variables to PHP?

PHP runs on the server before the page is sent to the user, JavaScript is run on the user's computer once it is received, so the PHP script has already executed.

If you want to pass a JavaScript value to a PHP script, you'd have to do an XMLHttpRequest to send the data back to the server.

Here's a previous question that you can follow for more information: Ajax Tutorial

Now if you just need to pass a form value to the server, you can also just do a normal form post, that does the same thing, but the whole page has to be refreshed.

<?php
if(isset($_POST))
{
  print_r($_POST);
}
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post">
  <input type="text" name="data" value="1" />
  <input type="submit" value="Submit" />
</form>

Clicking submit will submit the page, and print out the submitted data.

Change Bootstrap tooltip color

For the arrow color, you can use this:

.tooltip .tooltip-arrow {border-top: 5px solid red !important;}

Java: Clear the console

By combining all the given answers, this method should work on all environments:

public static void clearConsole() {
    try {
        if (System.getProperty("os.name").contains("Windows")) {
            new ProcessBuilder("cmd", "/c", "cls").inheritIO().start().waitFor();
        }
        else {
            System.out.print("\033\143");
        }
    } catch (IOException | InterruptedException ex) {}
}

keycloak Invalid parameter: redirect_uri

This error is also thrown when your User does not have the expected Role delegated in User definition(Set role for the Realm in drop down).

When to use StringBuilder in Java

Ralph's answer is fabulous. I would rather use StringBuilder class to build/decorate the String because the usage of it is more look like Builder pattern.

public String decorateTheString(String orgStr){
            StringBuilder builder = new StringBuilder();
            builder.append(orgStr);
            builder.deleteCharAt(orgStr.length()-1);
            builder.insert(0,builder.hashCode());
            return builder.toString();
}

It can be use as a helper/builder to build the String, not the String itself.

Append String in Swift

Strings concatenate in Swift language.

let string1 = "one"

let string2 = "two"

var concate = " (string1) (string2)"

playgroud output is "one two"

C# Get a control's position on a form

In my testing, both Hans Kesting's and Fredrik Mörk's solutions gave the same answer. But:

I found an interesting discrepancy in the answer using the methods of Raj More and Hans Kesting, and thought I'd share. Thanks to both though for their help; I can't believe such a method is not built into the framework.

Please note that Raj didn't write code and therefore my implementation could be different than he meant.

The difference I found was that the method from Raj More would often be two pixels greater (in both X and Y) than the method from Hans Kesting. I have not yet determined why this occurs. I'm pretty sure it has something to do with the fact that there seems to be a two-pixel border around the contents of a Windows form (as in, inside the form's outermost borders). In my testing, which was certainly not exhaustive to any extent, I've only come across it on controls that were nested. However, not all nested controls exhibit it. For example, I have a TextBox inside a GroupBox which exhibits the discrepancy, but a Button inside the same GroupBox does not. I cannot explain why.

Note that when the answers are equivalent, they consider the point (0, 0) to be inside the content border I mentioned above. Therefore I believe I'll consider the solutions from Hans Kesting and Fredrik Mörk to be correct but don't think I'll trust the solution I've implemented of Raj More's.

I also wondered exactly what code Raj More would have written, since he gave an idea but didn't provide code. I didn't fully understand the PointToScreen() method until I read this post: http://social.msdn.microsoft.com/Forums/en-US/netfxcompact/thread/aa91d4d8-e106-48d1-8e8a-59579e14f495

Here's my method for testing. Note that 'Method 1' mentioned in the comments is slightly different than Hans Kesting's.

private Point GetLocationRelativeToForm(Control c)
{
  // Method 1: walk up the control tree
  Point controlLocationRelativeToForm1 = new Point();
  Control currentControl = c;
  while (currentControl.Parent != null)
  {
    controlLocationRelativeToForm1.Offset(currentControl.Left, currentControl.Top);
    currentControl = currentControl.Parent;
  }

  // Method 2: determine absolute position on screen of control and form, and calculate difference
  Point controlScreenPoint = c.PointToScreen(Point.Empty);
  Point formScreenPoint = PointToScreen(Point.Empty);
  Point controlLocationRelativeToForm2 = controlScreenPoint - new Size(formScreenPoint);

  // Method 3: combine PointToScreen() and PointToClient()
  Point locationOnForm = c.FindForm().PointToClient(c.Parent.PointToScreen(c.Location));

  // Theoretically they should be the same
  Debug.Assert(controlLocationRelativeToForm1 == controlLocationRelativeToForm2);
  Debug.Assert(locationOnForm == controlLocationRelativeToForm1);
  Debug.Assert(locationOnForm == controlLocationRelativeToForm2);

  return controlLocationRelativeToForm1;
}

Adding a HTTP header to the Angular HttpClient doesn't send the header, why?

In the manual (https://angular.io/guide/http) I read: The HttpHeaders class is immutable, so every set() returns a new instance and applies the changes.

The following code works for me with angular-4:

 return this.http.get(url, {headers: new HttpHeaders().set('UserEmail', email ) });

How do I change data-type of pandas data frame to string with a defined format?

If you could reload this, you might be able to use dtypes argument.

pd.read_csv(..., dtype={'COL_NAME':'str'})

#1062 - Duplicate entry for key 'PRIMARY'

Repair the database by your domain provider cpanel.

Or see if you didnt merged something in the phpMyAdmin

Is it ok to scrape data from Google results?

Google thrives on scraping websites of the world...so if it was "so illegal" then even Google won't survive ..of course other answers mention ways of mitigating IP blocks by Google. One more way to explore avoiding captcha could be scraping at random times (dint try) ..Moreover, I have a feeling, that if we provide novelty or some significant processing of data then it sounds fine at least to me...if we are simply copying a website.. or hampering its business/brand in some way...then it is bad and should be avoided..on top of it all...if you are a startup then no one will fight you as there is no benefit.. but if your entire premise is on scraping even when you are funded then you should think of more sophisticated ways...alternative APIs..eventually..Also Google keeps releasing (or depricating) fields for its API so what you want to scrap now may be in roadmap of new Google API releases..

regular expression for Indian mobile numbers

Here you go :)

^[7-9][0-9]{9}$

Way to create multiline comments in Bash?

After reading the other answers here I came up with the below, which IMHO makes it really clear it's a comment. Especially suitable for in-script usage info:

<< ////

Usage:
This script launches a spaceship to the moon. It's doing so by 
leveraging the power of the Fifth Element, AKA Leeloo.
Will only work if you're Bruce Willis or a relative of Milla Jovovich.

////

As a programmer, the sequence of slashes immediately registers in my brain as a comment (even though slashes are normally used for line comments).

Of course, "////" is just a string; the number of slashes in the prefix and the suffix must be equal.

php return 500 error but no error log

Copy and paste the following into a new .htaccess file and place it on your website's root folder :

php_flag  display_errors                  on
php_flag  display_startup_errors          on

Errors will be shown directly in your page.

That's the best way to debug quickly but don't use it for long time because it could be a security breach.

Center Oversized Image in Div

Put a large div inside the div, center that, and the center the image inside that div.

This centers it horizontally:

HTML:

<div class="imageContainer">
  <div class="imageCenterer">
    <img src="http://placekitten.com/200/200" />
  </div>
</div>

CSS:

.imageContainer {
  width: 100px;
  height: 100px;
  overflow: hidden;
  position: relative;
}
.imageCenterer {
  width: 1000px;
  position: absolute;
  left: 50%;
  top: 0;
  margin-left: -500px;
}
.imageCenterer img {
  display: block;
  margin: 0 auto;
}

Demo: http://jsfiddle.net/Guffa/L9BnL/

To center it vertically also, you can use the same for the inner div, but you would need the height of the image to place it absolutely inside it.

Duplicate line in Visual Studio Code

Ubuntu :

  • Duplicate Line Up : Ctrl + Alt + Shift + 8
  • Duplicate Line Down : Ctrl + Alt + Shift + 2

MVVM Passing EventArgs As Command Parameter

As an adaption of @Mike Fuchs answer, here's an even smaller solution. I'm using the Fody.AutoDependencyPropertyMarker to reduce some of the boiler plate.

The Class

public class EventCommand : TriggerAction<DependencyObject>
{
    [AutoDependencyProperty]
    public ICommand Command { get; set; }

    protected override void Invoke(object parameter)
    {
        if (Command != null)
        {
            if (Command.CanExecute(parameter))
            {
                Command.Execute(parameter);
            }
        }
    }
}

The EventArgs

public class VisibleBoundsArgs : EventArgs
{
    public Rect VisibleVounds { get; }

    public VisibleBoundsArgs(Rect visibleBounds)
    {
        VisibleVounds = visibleBounds;
    }
}

The XAML

<local:ZoomableImage>
   <i:Interaction.Triggers>
      <i:EventTrigger EventName="VisibleBoundsChanged" >
         <local:EventCommand Command="{Binding VisibleBoundsChanged}" />
      </i:EventTrigger>
   </i:Interaction.Triggers>
</local:ZoomableImage>

The ViewModel

public ICommand VisibleBoundsChanged => _visibleBoundsChanged ??
                                        (_visibleBoundsChanged = new RelayCommand(obj => SetVisibleBounds(((VisibleBoundsArgs)obj).VisibleVounds)));

Last executed queries for a specific database

This works for me to find queries on any database in the instance. I'm sysadmin on the instance (check your privileges):

SELECT deqs.last_execution_time AS [Time], dest.text AS [Query], dest.*
FROM sys.dm_exec_query_stats AS deqs
CROSS APPLY sys.dm_exec_sql_text(deqs.sql_handle) AS dest
WHERE dest.dbid = DB_ID('msdb')
ORDER BY deqs.last_execution_time DESC

This is the same answer that Aaron Bertrand provided but it wasn't placed in an answer.

Different between parseInt() and valueOf() in java?

Look at Java sources: valueOf is using parseInt :

/**
 * Parses the specified string as a signed decimal integer value.
 *
 * @param string
 *            the string representation of an integer value.
 * @return an {@code Integer} instance containing the integer value
 *         represented by {@code string}.
 * @throws NumberFormatException
 *             if {@code string} cannot be parsed as an integer value.
 * @see #parseInt(String)
 */
public static Integer valueOf(String string) throws NumberFormatException {
    return valueOf(parseInt(string));
}

parseInt returns int

/**
 * Parses the specified string as a signed decimal integer value. The ASCII
 * character \u002d ('-') is recognized as the minus sign.
 *
 * @param string
 *            the string representation of an integer value.
 * @return the primitive integer value represented by {@code string}.
 * @throws NumberFormatException
 *             if {@code string} cannot be parsed as an integer value.
 */
public static int parseInt(String string) throws NumberFormatException {
    return parseInt(string, 10);
}

How do I calculate square root in Python?

sqrt=x**(1/2) is doing integer division. 1/2 == 0.

So you're computing x(1/2) in the first instance, x(0) in the second.

So it's not wrong, it's the right answer to a different question.

@Autowired - No qualifying bean of type found for dependency

This may help you:

I have the same exception in my project. After searching while I found that I am missing the @Service annotation to the class where I am implementing the interface which I want to @Autowired.

In your code you can add the @Service annotation to MailManager class.

@Transactional
@Service
public class MailManager extends AbstractManager implements IMailManager {

Resolving IP Address from hostname with PowerShell

This worked well for my purpose

$ping = ping -4 $env:COMPUTERNAME
$ip = $ping.Item(2)
$ip = $ip.Substring(11,11)

Can VS Code run on Android?

There is a browser-based implementation of VSC that allows you to run it on a browser on your Android (or any other) device. Check it out here:

https://stackblitz.com/

NUnit Unit tests not showing in Test Explorer with Test Adapter installed

If your test project is set to target a 64bit platform, the tests won't show up in the NUnit Test Adapter.

Java Object Null Check for method

You can add a guard condition to the method to ensure books is not null and then check for null when iterating the array:

public static double calculateInventoryTotal(Book[] books)
{
    if(books == null){
        throw new IllegalArgumentException("Books cannot be null");
    }

    double total = 0;

    for (int i = 0; i < books.length; i++)
    {
        if(books[i] != null){
            total += books[i].getPrice();
        }
    }

    return total;
}

What is the difference between C++ and Visual C++?

VC++ is not actually a language but is commonly referred to like one. When VC++ is referred to as a language, it usually means Microsoft's implementation of C++, which contains various knacks that do not exist in regular C++, such as the __super keyword. It is similar to the various GNU extensions to the C language that are implemented in GCC.

How to execute an Oracle stored procedure via a database link

The syntax is

EXEC mySchema.myPackage.myProcedure@myRemoteDB( 'someParameter' );

java.lang.NoClassDefFoundError in junit

even Junit4.11.jar doesnot have the hamcrest-core.jar. I added explicitly in the classpath and the issue was resolved.

How do I show the changes which have been staged?

By default git diff is used to show the changes which is not added to the list of git updated files. But if you want to show the changes which is added or stagged then you need to provide extra options that will let git know that you are interested in stagged or added files diff .

$ git diff          # Default Use
$ git diff --cached # Can be used to show difference after adding the files 
$ git diff --staged # Same as 'git diff --cached' mostly used with latest version of git 

Example

$ git diff 
diff --git a/x/y/z.js  b/x/y/z.js index 98fc22b..0359d84 100644
--- a/x/y/z.js 
+++ b/x/y/z.js @@ -43,7 +43,7 @@ var a = function (tooltip) {

-        if (a)
+        if (typeof a !== 'undefined')
             res = 1;
         else
             res = 2;

$ git add x/y/z.js
$ git diff
$

Once you added the files , you can't use default of 'git diff' .You have to do like this:-

$ git diff --cached
diff --git a/x/y/z.js  b/x/y/z.js index 98fc22b..0359d84 100644
    --- a/x/y/z.js 
    +++ b/x/y/z.js @@ -43,7 +43,7 @@ var a = function (tooltip) {

    -        if (a)
    +        if (typeof a !== 'undefined')
                 res = 1;
             else
                 res = 2;

Can we cast a generic object to a custom object type in javascript?

This worked for me. It's simple for simple objects.

_x000D_
_x000D_
class Person {_x000D_
  constructor(firstName, lastName) {_x000D_
    this.firstName = firstName;_x000D_
    this.lastName = lastName;_x000D_
  }_x000D_
  getFullName() {_x000D_
    return this.lastName + " " + this.firstName;_x000D_
  }_x000D_
_x000D_
  static class(obj) {_x000D_
    return new Person(obj.firstName, obj.lastName);_x000D_
  }_x000D_
}_x000D_
_x000D_
var person1 = {_x000D_
  lastName: "Freeman",_x000D_
  firstName: "Gordon"_x000D_
};_x000D_
_x000D_
var gordon = Person.class(person1);_x000D_
console.log(gordon.getFullName());
_x000D_
_x000D_
_x000D_

I was also searching for a simple solution, and this is what I came up with, based on all other answers and my research. Basically, class Person has another constructor, called 'class' which works with a generic object of the same 'format' as Person. I hope this might help somebody as well.

How can I post an array of string to ASP.NET MVC Controller without a form?

As I discussed here ,

if you want to pass custom JSON object to MVC action then you can use this solution, it works like a charm.

public string GetData() {
  // InputStream contains the JSON object you've sent
  String jsonString = new StreamReader(this.Request.InputStream).ReadToEnd();

  // Deserialize it to a dictionary
  var dic =
    Newtonsoft.Json.JsonConvert.DeserializeObject < Dictionary < String,
    dynamic >> (jsonString);

  string result = "";

  result += dic["firstname"] + dic["lastname"];

  // You can even cast your object to their original type because of 'dynamic' keyword
  result += ", Age: " + (int) dic["age"];

  if ((bool) dic["married"])
    result += ", Married";

  return result;
}

The real benefit of this solution is that you don't require to define a new class for each combination of arguments and beside that, you can cast your objects to their original types easily.

You can use a helper method like this to facilitate your job:

public static Dictionary < string, dynamic > GetDic(HttpRequestBase request) {
  String jsonString = new StreamReader(request.InputStream).ReadToEnd();
  return Newtonsoft.Json.JsonConvert.DeserializeObject < Dictionary < string, dynamic >> (jsonString);
}

Format decimal for percentage values?

Use the P format string. This will vary by culture:

String.Format("Value: {0:P2}.", 0.8526) // formats as 85.26 % (varies by culture)

How to specify the port an ASP.NET Core application is hosted on?

If using dotnet run

dotnet run --urls="http://localhost:5001"

Aggregate multiple columns at once

You could try:

agg <- aggregate(list(x$val1, x$val2, x$val3, x$val4), by = list(x$id1, x$id2), mean)

Is there any publicly accessible JSON data source to test with real world data?

Tumblr has a public API that provides JSON. You can get a dump of posts using a simple url like http://puppygifs.tumblr.com/api/read/json.

Is there a way I can capture my iPhone screen as a video?

I've continued to research this item myself, and it does appear to remain beyond us at this point.

I even tried buying a Apple Composite AV Cable, but it doesn't capture screen, just video playing like YouTube, etc.

So I decided to go with the iShowU path and that has worked out well so far.

Thanks Guys!

How to force two figures to stay on the same page in LaTeX?

If you want them both on the same page and they'll both take up basically the whole page, then the best idea is to tell LaTeX to put them both on a page of their own!

\begin{figure}[p]

It would probably be against sound typographic principles (e.g., ugly) to have two figures on a page with only a few lines of text above or below them.


By the way, the reason that [!h] works is because it's telling LaTeX to override its usual restrictions on how much space should be devoted to floats on a page with text. As implied above, there's a reason the restrictions are there. Which isn't to say they can be loosened somewhat; see the FAQ on doing that.

qmake: could not find a Qt installation of ''

For others in my situation, the solution was:

qmake -qt=qt5

This was on Ubuntu 14.04 after install qt5-qmake. qmake was a symlink to qtchooser which takes the -qt argument.

Importing data from a JSON file into R

jsonlite will import the JSON into a data frame. It can optionally flatten nested objects. Nested arrays will be data frames.

> library(jsonlite)
> winners <- fromJSON("winners.json", flatten=TRUE)
> colnames(winners)
[1] "winner" "votes" "startPrice" "lastVote.timestamp" "lastVote.user.name" "lastVote.user.user_id"
> winners[,c("winner","startPrice","lastVote.user.name")]
    winner startPrice lastVote.user.name
1 68694999          0              Lamur
> winners[,c("votes")]
[[1]]
                            ts user.name user.user_id
1 Thu Mar 25 03:13:01 UTC 2010     Lamur     68694999
2 Thu Mar 25 03:13:08 UTC 2010     Lamur     68694999

Difference between <? super T> and <? extends T> in Java

Based on Bert F's answer I would like to explain my understanding.

Lets say we have 3 classes as

public class Fruit{}

public class Melon extends Fruit{}

public class WaterMelon extends Melon{}

Here We have

List<? extends Fruit> fruitExtendedList = …

//Says that I can be a list of any object as long as this object extends Fruit.

Ok now lets try to get some value from fruitExtendedList

Fruit fruit = fruitExtendedList.get(position)

//This is valid as it can only return Fruit or its subclass.

Again lets try

Melon melon = fruitExtendedList.get(position)

//This is not valid because fruitExtendedList can be a list of Fruit only, it may not be 
//list of Melon or WaterMelon and in java we cannot assign sub class object to 
//super class object reference without explicitly casting it.

Same is the case for

WaterMelon waterMelon = fruitExtendedList.get(position)

Now lets try to set some object in fruitExtendedList

Adding fruit object

fruitExtendedList.add(new Fruit())

//This in not valid because as we know fruitExtendedList can be a list of any 
//object as long as this object extends Fruit. So what if it was the list of  
//WaterMelon or Melon you cannot add Fruit to the list of WaterMelon or Melon.

Adding Melon object

fruitExtendedList.add(new Melon())

//This would be valid if fruitExtendedList was the list of Fruit but it may 
//not be, as it can also be the list of WaterMelon object. So, we see an invalid 
//condition already.

Finally let try to add WaterMelon object

fruitExtendedList.add(new WaterMelon())

//Ok, we got it now we can finally write to fruitExtendedList as WaterMelon 
//can be added to the list of Fruit or Melon as any superclass reference can point 
//to its subclass object.

But wait what if someone decides to make a new type of Lemon lets say for arguments sake SaltyLemon as

public class SaltyLemon extends Lemon{}

Now fruitExtendedList can be list of Fruit, Melon, WaterMelon or SaltyLemon.

So, our statement

fruitExtendedList.add(new WaterMelon())

is not valid either.

Basically we can say that we cannot write anything to a fruitExtendedList.

This sums up List<? extends Fruit>

Now lets see

List<? super Melon> melonSuperList= …

//Says that I can be a list of anything as long as its object has super class of Melon.

Now lets try to get some value from melonSuperList

Fruit fruit = melonSuperList.get(position)

//This is not valid as melonSuperList can be a list of Object as in java all 
//the object extends from Object class. So, Object can be super class of Melon and 
//melonSuperList can be a list of Object type

Similarly Melon, WaterMelon or any other object cannot be read.

But note that we can read Object type instances

Object myObject = melonSuperList.get(position)

//This is valid because Object cannot have any super class and above statement 
//can return only Fruit, Melon, WaterMelon or Object they all can be referenced by
//Object type reference.

Now, lets try to set some value from melonSuperList.

Adding Object type object

melonSuperList.add(new Object())

//This is not valid as melonSuperList can be a list of Fruit or Melon.
//Note that Melon itself can be considered as super class of Melon.

Adding Fruit type object

melonSuperList.add(new Fruit())

//This is also not valid as melonSuperList can be list of Melon

Adding Melon type object

melonSuperList.add(new Melon())

//This is valid because melonSuperList can be list of Object, Fruit or Melon and in 
//this entire list we can add Melon type object.

Adding WaterMelon type object

melonSuperList.add(new WaterMelon())

//This is also valid because of same reason as adding Melon

To sum it up we can add Melon or its subclass in melonSuperList and read only Object type object.

Enable/Disable a dropdownbox in jquery

$("#chkdwn2").change(function(){
       $("#dropdown").slideToggle();
});

JsFiddle

How to make padding:auto work in CSS?

You can reset the padding (and I think everything else) with initial to the default.

p {
    padding: initial;
}

How to reverse apply a stash?

According to the git-stash manpage, "A stash is represented as a commit whose tree records the state of the working directory, and its first parent is the commit at HEAD when the stash was created," and git stash show -p gives us "the changes recorded in the stash as a diff between the stashed state and its original parent.

To keep your other changes intact, use git stash show -p | patch --reverse as in the following:

$ git init
Initialized empty Git repository in /tmp/repo/.git/

$ echo Hello, world >messages

$ git add messages

$ git commit -am 'Initial commit'
[master (root-commit)]: created 1ff2478: "Initial commit"
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 messages

$ echo Hello again >>messages

$ git stash

$ git status
# On branch master
nothing to commit (working directory clean)

$ git stash apply
# On branch master
# Changed but not updated:
#   (use "git add <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#       modified:   messages
#
no changes added to commit (use "git add" and/or "git commit -a")

$ echo Howdy all >>messages

$ git diff
diff --git a/messages b/messages
index a5c1966..eade523 100644
--- a/messages
+++ b/messages
@@ -1 +1,3 @@
 Hello, world
+Hello again
+Howdy all

$ git stash show -p | patch --reverse
patching file messages
Hunk #1 succeeded at 1 with fuzz 1.

$ git diff
diff --git a/messages b/messages
index a5c1966..364fc91 100644
--- a/messages
+++ b/messages
@@ -1 +1,2 @@
 Hello, world
+Howdy all

Edit:

A light improvement to this is to use git apply in place of patch:

git stash show -p | git apply --reverse

Alternatively, you can also use git apply -R as a shorthand to git apply --reverse.

I've been finding this really handy lately...

Blur or dim background when Android PopupWindow active

Maybe this repo will help for you:BasePopup

This is my repo, which is used to solve various problems of PopupWindow.

In the case of using the library, if you need to blur the background, just call setBlurBackgroundEnable(true).

See the wiki for more details.(Language in zh-cn)

BasePopup:wiki

What's an appropriate HTTP status code to return by a REST API service for a validation failure?

A duplicate in the database should be a 409 CONFLICT.

I recommend using 422 UNPROCESSABLE ENTITY for validation errors.

I give a longer explanation of 4xx codes here: http://parker0phil.com/2014/10/16/REST_http_4xx_status_codes_syntax_and_sematics/

Git - What is the difference between push.default "matching" and "simple"

From GIT documentation: Git Docs

Below gives the full information. In short, simple will only push the current working branch and even then only if it also has the same name on the remote. This is a very good setting for beginners and will become the default in GIT 2.0

Whereas matching will push all branches locally that have the same name on the remote. (Without regard to your current working branch ). This means potentially many different branches will be pushed, including those that you might not even want to share.

In my personal usage, I generally use a different option: current which pushes the current working branch, (because I always branch for any changes). But for a beginner I'd suggest simple

push.default
Defines the action git push should take if no refspec is explicitly given. Different values are well-suited for specific workflows; for instance, in a purely central workflow (i.e. the fetch source is equal to the push destination), upstream is probably what you want. Possible values are:

nothing - do not push anything (error out) unless a refspec is explicitly given. This is primarily meant for people who want to avoid mistakes by always being explicit.

current - push the current branch to update a branch with the same name on the receiving end. Works in both central and non-central workflows.

upstream - push the current branch back to the branch whose changes are usually integrated into the current branch (which is called @{upstream}). This mode only makes sense if you are pushing to the same repository you would normally pull from (i.e. central workflow).

simple - in centralized workflow, work like upstream with an added safety to refuse to push if the upstream branch's name is different from the local one.

When pushing to a remote that is different from the remote you normally pull from, work as current. This is the safest option and is suited for beginners.

This mode will become the default in Git 2.0.

matching - push all branches having the same name on both ends. This makes the repository you are pushing to remember the set of branches that will be pushed out (e.g. if you always push maint and master there and no other branches, the repository you push to will have these two branches, and your local maint and master will be pushed there).

To use this mode effectively, you have to make sure all the branches you would push out are ready to be pushed out before running git push, as the whole point of this mode is to allow you to push all of the branches in one go. If you usually finish work on only one branch and push out the result, while other branches are unfinished, this mode is not for you. Also this mode is not suitable for pushing into a shared central repository, as other people may add new branches there, or update the tip of existing branches outside your control.

This is currently the default, but Git 2.0 will change the default to simple.

Setting Curl's Timeout in PHP

You can't run the request from a browser, it will timeout waiting for the server running the CURL request to respond. The browser is probably timing out in 1-2 minutes, the default network timeout.

You need to run it from the command line/terminal.

Find closest previous element jQuery

see http://api.jquery.com/prev/

var link = $("#me").parent("div").prev("h3").find("b");
alert(link.text());

see http://jsfiddle.net/gBwLq/

How do I call a Django function on button click?

here is a pure-javascript, minimalistic approach. I use JQuery but you can use any library (or even no libraries at all).

<html>
    <head>
        <title>An example</title>
        <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
        <script>
            function call_counter(url, pk) {
                window.open(url);
                $.get('YOUR_VIEW_HERE/'+pk+'/', function (data) {
                    alert("counter updated!");
                });
            }
        </script>
    </head>
    <body>
        <button onclick="call_counter('http://www.google.com', 12345);">
            I update object 12345
        </button>
        <button onclick="call_counter('http://www.yahoo.com', 999);">
            I update object 999
        </button>
    </body>
</html>

Alternative approach

Instead of placing the JavaScript code, you can change your link in this way:

<a target="_blank" 
    class="btn btn-info pull-right" 
    href="{% url YOUR_VIEW column_3_item.pk %}/?next={{column_3_item.link_for_item|urlencode:''}}">
    Check It Out
</a>

and in your views.py:

def YOUR_VIEW_DEF(request, pk):
    YOUR_OBJECT.objects.filter(pk=pk).update(views=F('views')+1)
    return HttpResponseRedirect(request.GET.get('next')))

How to convert from Hex to ASCII in JavaScript?

** for Hexa to String**

let input  = '32343630';

Note : let output = new Buffer(input, 'hex'); // this is deprecated

let buf = Buffer.from(input, "hex");
let data = buf.toString("utf8");

jQuery get value of selected radio button

In case you don't know the sepcific name or want to check all radio inputs in a form, you can use a global var to check for each radio group the value only once: `

        var radio_name = "";
        $("form).find(":radio").each(function(){
            if (!radio_name || radio_name != $(this).attr('name')) {
                radio_name = $(this).attr('name');
                var val = $('input[name="'+radio_name+'"]:checked').val();
                if (!val) alert($('input[name="'+radio_name+'"]:checked').val());
            }
        });`

List of encodings that Node.js supports

If the above solution does not work for you it is may be possible to obtain the same result with the following pure nodejs code. The above did not work for me and resulted in a compilation exception when running 'npm install iconv' on OSX:

npm install iconv

npm WARN package.json [email protected] No README.md file found!
npm http GET https://registry.npmjs.org/iconv
npm http 200 https://registry.npmjs.org/iconv
npm http GET https://registry.npmjs.org/iconv/-/iconv-2.0.4.tgz
npm http 200 https://registry.npmjs.org/iconv/-/iconv-2.0.4.tgz

> [email protected] install /Users/markboyd/git/portal/app/node_modules/iconv
> node-gyp rebuild

gyp http GET http://nodejs.org/dist/v0.10.1/node-v0.10.1.tar.gz
gyp http 200 http://nodejs.org/dist/v0.10.1/node-v0.10.1.tar.gz
xcode-select: Error: No Xcode is selected. Use xcode-select -switch <path-to-xcode>, or see the xcode-select manpage (man xcode-select) for further information.

fs.readFileSync() returns a Buffer if no encoding is specified. And Buffer has a toString() method that will convert to UTF8 if no encoding is specified giving you the file's contents. See the nodejs documentation. This worked for me.

How do I invoke a Java method when given the method name as a string?

Object obj;

Method method = obj.getClass().getMethod("methodName", null);

method.invoke(obj, null);

Commit only part of a file in Git

I believe that git add -e myfile is the easiest way (my preference at least) since it simply opens a text editor and lets you choose which line you want to stage and which line you don't. Regarding editing commands:

added content:

Added content is represented by lines beginning with "+". You can prevent staging any addition lines by deleting them.

removed content:

Removed content is represented by lines beginning with "-". You can prevent staging their removal by converting the "-" to a " " (space).

modified content:

Modified content is represented by "-" lines (removing the old content) followed by "+" lines (adding the replacement content). You can prevent staging the modification by converting "-" lines to " ", and removing "+" lines. Beware that modifying only half of the pair is likely to introduce confusing changes to the index.

Every details about git add are available on git --help add

Switching a DIV background image with jQuery

This is a fairly simple response changes the background of the site with a list of items

function randomToN(maxVal) {
    var randVal = Math.random() * maxVal;
    return typeof 0 == 'undefined' ? Math.round(randVal) : randVal.toFixed(0);
};
var list = [ "IMG0.EXT", "IMG2.EXT","IMG3.EXT" ], // Images
    ram = list[parseFloat(randomToN(list.length))], // Random 1 to n
    img = ram == undefined || ram == null ? list[0] : ram; // Detect null
$("div#ID").css("backgroundImage", "url(" + img + ")"); // push de background

Responsive css styles on mobile devices ONLY

Yes, this can be done via javascript feature detection ( or browser detection , e.g. Modernizr ) . Then, use yepnope.js to load required resources ( JS and/or CSS )

What processes are using which ports on unix?

Which process uses port in unix;

1. netstat -Aan | grep port

root> netstat -Aan | grep 3872

output> f1000e000bb5c3b8 tcp 0 0 *.3872 . LISTEN

2. rmsock f1000e000bb5c3b8 tcpcb

output> The socket 0xf1000e000bb5c008 is being held by proccess 13959354 (java).

3. ps -ef | grep 13959354

Select unique values with 'select' function in 'dplyr' library

The dplyr select function selects specific columns from a data frame. To return unique values in a particular column of data, you can use the group_by function. For example:

library(dplyr)

# Fake data
set.seed(5)
dat = data.frame(x=sample(1:10,100, replace=TRUE))

# Return the distinct values of x
dat %>%
  group_by(x) %>%
  summarise() 

    x
1   1
2   2
3   3
4   4
5   5
6   6
7   7
8   8
9   9
10 10

If you want to change the column name you can add the following:

dat %>%
  group_by(x) %>%
  summarise() %>%
  select(unique.x=x)

This both selects column x from among all the columns in the data frame that dplyr returns (and of course there's only one column in this case) and changes its name to unique.x.

You can also get the unique values directly in base R with unique(dat$x).

If you have multiple variables and want all unique combinations that appear in the data, you can generalize the above code as follows:

set.seed(5)
dat = data.frame(x=sample(1:10,100, replace=TRUE), 
                 y=sample(letters[1:5], 100, replace=TRUE))

dat %>% 
  group_by(x,y) %>%
  summarise() %>%
  select(unique.x=x, unique.y=y)

Display QImage with QtGui

Thanks All, I found how to do it, which is the same as Dave and Sergey:

I am using QT Creator:

In the main GUI window create using the drag drop GUI and create label (e.g. "myLabel")

In the callback of the button (clicked) do the following using the (*ui) pointer to the user interface window:

void MainWindow::on_pushButton_clicked()
{
     QImage imageObject;
     imageObject.load(imagePath);
     ui->myLabel->setPixmap(QPixmap::fromImage(imageObject));

     //OR use the other way by setting the Pixmap directly

     QPixmap pixmapObject(imagePath");
     ui->myLabel2->setPixmap(pixmapObject);
}

Can't bind to 'formGroup' since it isn't a known property of 'form'

import { FormsModule, ReactiveFormsModule } from '@angular/forms'; and add it in imports array in the app-module.ts file.

How do I configure HikariCP in my Spring Boot app in my application.properties files?

You could simply make use of application.yml/application.properties only. There is no need to explicitly create any DataSource Bean

You need to exclude tomcat-jdbc as mentioned by ydemartino

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
    <exclusions>
        <exclusion>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jdbc</artifactId>
        </exclusion>
    </exclusions>
</dependency>

As you won't create DataSource bean, you have to explicitly specify using Hikari through spring.datasource.type with value com.zaxxer.hikari.HikariDataSource in application.yml / application.properties

spring:
    datasource:
        hikari:
            connection-test-query: SELECT 1 FROM DUAL
            minimum-idle: 1
            maximum-pool-size: 5
            pool-name: yourPoolName
            auto-commit: false
        driver-class-name: com.mysql.jdbc.Driver
        url: jdbc:mysql://localhost:3306/myDb
        username: login
        password: password
        type: com.zaxxer.hikari.HikariDataSource

In your application.yml / application.properties, you could configure Hikari specific parameters such as pool size etc in spring.datasource.hikari.*

Using HTTPS with REST in Java

When you say "is there an easier way to... trust this cert", that's exactly what you're doing by adding the cert to your Java trust store. And this is very, very easy to do, and there's nothing you need to do within your client app to get that trust store recognized or utilized.

On your client machine, find where your cacerts file is (that's your default Java trust store, and is, by default, located at <java-home>/lib/security/certs/cacerts.

Then, type the following:

keytool -import -alias <Name for the cert> -file <the .cer file> -keystore <path to cacerts>

That will import the cert into your trust store, and after this, your client app will be able to connect to your Grizzly HTTPS server without issue.

If you don't want to import the cert into your default trust store -- i.e., you just want it to be available to this one client app, but not to anything else you run on your JVM on that machine -- then you can create a new trust store just for your app. Instead of passing keytool the path to the existing, default cacerts file, pass keytool the path to your new trust store file:

keytool -import -alias <Name for the cert> -file <the .cer file> -keystore <path to new trust store>

You'll be asked to set and verify a new password for the trust store file. Then, when you start your client app, start it with the following parameters:

java -Djavax.net.ssl.trustStore=<path to new trust store> -Djavax.net.ssl.trustStorePassword=<trust store password>

Easy cheesy, really.

Why should C++ programmers minimize use of 'new'?

To a great extent, that's someone elevating their own weaknesses to a general rule. There's nothing wrong per se with creating objects using the new operator. What there is some argument for is that you have to do so with some discipline: if you create an object you need to make sure it's going to be destroyed.

The easiest way of doing that is to create the object in automatic storage, so C++ knows to destroy it when it goes out of scope:

 {
    File foo = File("foo.dat");

    // do things

 }

Now, observe that when you fall off that block after the end-brace, foo is out of scope. C++ will call its dtor automatically for you. Unlike Java, you don't need to wait for the GC to find it.

Had you written

 {
     File * foo = new File("foo.dat");

you would want to match it explicitly with

     delete foo;
  }

or even better, allocate your File * as a "smart pointer". If you aren't careful about that it can lead to leaks.

The answer itself makes the mistaken assumption that if you don't use new you don't allocate on the heap; in fact, in C++ you don't know that. At most, you know that a small amout of memory, say one pointer, is certainly allocated on the stack. However, consider if the implementation of File is something like

  class File {
    private:
      FileImpl * fd;
    public:
      File(String fn){ fd = new FileImpl(fn);}

then FileImpl will still be allocated on the stack.

And yes, you'd better be sure to have

     ~File(){ delete fd ; }

in the class as well; without it, you'll leak memory from the heap even if you didn't apparently allocate on the heap at all.

Count number of cells with any value (string or number) in a column in Google Docs Spreadsheet

An additional trick beside using =COUNTIF(...) and =COUNTA(...) is:

=COUNTBLANK(A2:C100)

That will count all the empty cells.

This is useful for:

  • empty cells that doesn't contain data
  • formula that return blank or null
  • survey with missing answer fields which can be used for diff criterias

Find length (size) of an array in jquery

       var mode = [];
                $("input[name='mode[]']:checked").each(function(i) {
                    mode.push($(this).val());
                })
 if(mode.length == 0)
                {
                   alert('Please select mode!')
                };

Find files containing a given text

Sounds like a perfect job for grep or perhaps ack

Or this wonderful construction:

find . -type f \( -name *.php -o -name *.html -o -name *.js \) -exec grep "document.cookie\|setcookie" /dev/null {} \;

Android widget: How to change the text of a button

I had a button in my layout.xml that was defined as a View as in:

final View myButton = findViewById(R.id.button1);

I was not able to change the text on it until I also defined it as a button:

final View vButton = findViewById(R.id.button1);
final Button bButton = (Button) findViewById(R.id.button1);

When I needed to change the text, I used the bButton.setText("Some Text"); and when I wanted to alter the view, I used the vButton.

Worked great!

Java - using System.getProperty("user.dir") to get the home directory

Program to get the current working directory=user.dir

public class CurrentDirectoryExample {

    public static void main(String args[]) {

        String current = System.getProperty("user.dir");
        System.out.println("Current working directory in Java : " + current);
    }
}

center MessageBox in parent form

From a comment on Joel Spolsky's blog:

A Messagebox is always centered on the screen. You can provide an owner, but that is just for Z-order, not centering. The only way is to use Win32 hooks and center it yourself. You can find code doing that online if you search for it.

Much easier is to just write your own message box class and add centering functionality. Then you can also add default captioning, Do not show again-checkbox and making them modeless.

"Win32 hooks" probably refers to using SetWindowsHookEx as shown in this example.

MySQL direct INSERT INTO with WHERE clause

INSERT syntax cannot have WHERE but you can use UPDATE.

The syntax is as follows:

UPDATE table_name

SET column1 = value1, column2 = value2, ...

WHERE condition;

Creating a procedure in mySql with parameters

I figured it out now. Here's the correct answer

CREATE PROCEDURE checkUser 
(
   brugernavn1 varchar(64),
   password varchar(64)
) 
BEGIN 
   SELECT COUNT(*) FROM bruger 
   WHERE bruger.brugernavn=brugernavn1 
   AND bruger.pass=password; 
END; 

@ points to a global var in mysql. The above syntax is correct.

How to select true/false based on column value?

At least in Postgres you can use the following statement:

SELECT EntityID, EntityName, EntityProfile IS NOT NULL AS HasProfile FROM Entity

Adding delay between execution of two following lines

You can use the NSThread method:

[NSThread sleepForTimeInterval: delay];

However, if you do this on the main thread you'll block the app, so only do this on a background thread.


or in Swift

NSThread.sleepForTimeInterval(delay)

in Swift 3

Thread.sleep(forTimeInterval: delay)

jQuery : select all element with custom attribute

As described by the link I've given in comment, this

$('p[MyTag]').each(function(index) {
  document.write(index + ': ' + $(this).text() + "<br>");});

works (playable example).

How do I delete an exported environment variable?

As mentioned in the above answers, unset GNUPLOT_DRIVER_DIR should work if you have used export to set the variable. If you have set it permanently in ~/.bashrc or ~/.zshrc then simply removing it from there will work.

sql select with column name like

Blorgbeard had a great answer for SQL server. If you have a MySQL server like mine then the following will allow you to select the information from columns where the name is like some key phrase. You just have to substitute the table name, database name, and keyword.

SET @columnnames = (SELECT concat("`",GROUP_CONCAT(`COLUMN_NAME` SEPARATOR "`, `"),"`") 
FROM `INFORMATION_SCHEMA`.`COLUMNS` 
WHERE `TABLE_SCHEMA`='your_database' 
    AND `TABLE_NAME`='your_table'
    AND COLUMN_NAME LIKE "%keyword%");

SET @burrito = CONCAT("SELECT ",@columnnames," FROM your_table");

PREPARE result FROM @burrito;
EXECUTE result;

Android Studio - Importing external Library/Jar

I use android studio 0.8.6 and for importing external library in project , paste that library in libs folder and inside build.gradle write path of that library inside dependencies like this compile files('libs/google-play-services.jar')

Laravel Eloquent get results grouped by days

Warning: untested code.

$dailyData = DB::table('page_views')
    ->select('created_at', DB::raw('count(*) as views'))
    ->groupBy('created_at')
    ->get();

CentOS 7 and Puppet unable to install nc

You can use a case in this case, to separate versions one example is using FACT os (which returns the version etc of your system... the command facter will return the details:

root@sytem# facter -p os
{"name"=>"CentOS", "family"=>"RedHat", "release"=>{"major"=>"7", "minor"=>"0", "full"=>"7.0.1406"}}

#we capture release hash
$curr_os = $os['release']

case $curr_os['major'] {
  '7': { .... something }
  *: {something}
}

That is an fast example, Might have typos, or not exactly working. But using system facts you can see what happens.

The OS fact provides you 3 main variables: name, family, release... Under release you have a small dictionary with more information about your os! combining these you can create cases to meet your targets.

Cannot find the declaration of element 'beans'

Use this to solve your problem:

<context:annotation-config/>

How to update a claim in ASP.NET Identity?

I am using a .net core 2.2 app and used the following solution: in my statup.cs

public void ConfigureServices(IServiceCollection services)
        {
        ...
           services.AddIdentity<IdentityUser, IdentityRole>(options =>
               {
                  ...
               })
               .AddEntityFrameworkStores<AdminDbContext>()
               .AddDefaultTokenProviders()
               .AddSignInManager();

usage

  private readonly SignInManager<IdentityUser> _signInManager;


        public YourController(
                                    ...,
SignInManager<IdentityUser> signInManager)
        {
           ...
            _signInManager = signInManager;
        }

 public async Task<IActionResult> YourMethod() // <-NOTE IT IS ASYNC
        {
                var user = _userManager.FindByNameAsync(User.Identity.Name).Result;
                var claimToUse = ClaimsHelpers.CreateClaim(ClaimTypes.ActiveCompany, JsonConvert.SerializeObject(cc));
                var claimToRemove = _userManager.GetClaimsAsync(user).Result
                    .FirstOrDefault(x => x.Type == ClaimTypes.ActiveCompany.ToString());
                if (claimToRemove != null)
                {
                    var result = _userManager.ReplaceClaimAsync(user, claimToRemove, claimToUse).Result;
                    await _signInManager.RefreshSignInAsync(user); //<--- THIS
                }
                else ...
              

Simple working Example of json.net in VB.net

Imports Newtonsoft.Json.Linq

Dim json As JObject = JObject.Parse(Me.TextBox1.Text)
MsgBox(json.SelectToken("Venue").SelectToken("ID"))

Automating the InvokeRequired code pattern

Here's an improved/combined version of Lee's, Oliver's and Stephan's answers.

public delegate void InvokeIfRequiredDelegate<T>(T obj)
    where T : ISynchronizeInvoke;

public static void InvokeIfRequired<T>(this T obj, InvokeIfRequiredDelegate<T> action)
    where T : ISynchronizeInvoke
{
    if (obj.InvokeRequired)
    {
        obj.Invoke(action, new object[] { obj });
    }
    else
    {
        action(obj);
    }
} 

The template allows for flexible and cast-less code which is much more readable while the dedicated delegate provides efficiency.

progressBar1.InvokeIfRequired(o => 
{
    o.Style = ProgressBarStyle.Marquee;
    o.MarqueeAnimationSpeed = 40;
});

Log4j: How to configure simplest possible file logging?

I have one generic log4j.xml file for you:

<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd" >
<log4j:configuration debug="false">

    <appender name="default.console" class="org.apache.log4j.ConsoleAppender">
        <param name="target" value="System.out" />
        <param name="threshold" value="debug" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d{ISO8601} %-5p [%c{1}] - %m%n" />
        </layout>
    </appender>

    <appender name="default.file" class="org.apache.log4j.FileAppender">
        <param name="file" value="/log/mylogfile.log" />
        <param name="append" value="false" />
        <param name="threshold" value="debug" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d{ISO8601} %-5p [%c{1}] - %m%n" />
        </layout>
    </appender>

    <appender name="another.file" class="org.apache.log4j.FileAppender">
        <param name="file" value="/log/anotherlogfile.log" />
        <param name="append" value="false" />
        <param name="threshold" value="debug" />
        <layout class="org.apache.log4j.PatternLayout">
            <param name="ConversionPattern" value="%d{ISO8601} %-5p [%c{1}] - %m%n" />
        </layout>
    </appender>

    <logger name="com.yourcompany.SomeClass" additivity="false">
        <level value="debug" />
        <appender-ref ref="another.file" />
    </logger>

    <root>
        <priority value="info" />
        <appender-ref ref="default.console" />
        <appender-ref ref="default.file" />
    </root>
</log4j:configuration>

with one console, two file appender and one logger poiting to the second file appender instead of the first.

EDIT

In one of the older projects I have found a simple log4j.properties file:

# For the general syntax of property based configuration files see
# the documentation of org.apache.log4j.PropertyConfigurator.

# The root category uses two appenders: default.out and default.file.
# The first one gathers all log output, the latter only starting with 
# the priority INFO.
# The root priority is DEBUG, so that all classes can be logged unless 
# defined otherwise in more specific properties.
log4j.rootLogger=DEBUG, default.out, default.file

# System.out.println appender for all classes
log4j.appender.default.out=org.apache.log4j.ConsoleAppender
log4j.appender.default.out.threshold=DEBUG
log4j.appender.default.out.layout=org.apache.log4j.PatternLayout
log4j.appender.default.out.layout.ConversionPattern=%-5p %c: %m%n

log4j.appender.default.file=org.apache.log4j.FileAppender
log4j.appender.default.file.append=true
log4j.appender.default.file.file=/log/mylogfile.log
log4j.appender.default.file.threshold=INFO
log4j.appender.default.file.layout=org.apache.log4j.PatternLayout
log4j.appender.default.file.layout.ConversionPattern=%-5p %c: %m%n

For the description of all the layout arguments look here: log4j PatternLayout arguments

Java: export to an .jar file in eclipse

Go to file->export->JAR file, there you may select "Export generated class files and sources" and make sure that your project is selected, and all folder under there are also! Good luck!

Fastest way to convert string to integer in PHP

I personally feel casting is the prettiest.

$iSomeVar = (int) $sSomeOtherVar;

Should a string like 'Hello' be sent, it will be cast to integer 0. For a string such as '22 years old', it will be cast to integer 22. Anything it can't parse to a number becomes 0.

If you really do NEED the speed, I guess the other suggestions here are correct in assuming that coercion is the fastest.

String comparison in Python: is vs. ==

I would like to show a little example on how is and == are involved in immutable types. Try that:

a = 19998989890
b = 19998989889 +1
>>> a is b
False
>>> a == b
True

is compares two objects in memory, == compares their values. For example, you can see that small integers are cached by Python:

c = 1
b = 1
>>> b is c
True

You should use == when comparing values and is when comparing identities. (Also, from an English point of view, "equals" is different from "is".)

Freeing up a TCP/IP port?

The "netstat --programs" command will give you the process information, assuming you're the root user. Then you will have to kill the "offending" process which may well start up again just to annoy you.

Depending on what you're actually trying to achieve, solutions to that problem will vary based on the processes holding those ports. For example, you may need to disable services (assuming they're unneeded) or configure them to use a different port (if you do need them but you need that port more).

The declared package does not match the expected package ""

Make sure that Devices is defined as a source folder in the project properties.

Microsoft SQL Server 2005 service fails to start

I agree with Greg that the log is the best place to start. We've experienced something similar and the fix was to ensure that admins have full permissions to the registry location HKLM\System\CurrentControlSet\Control\WMI\Security prior to starting the installation. HTH.

CSS Float: Floating an image to the left of the text

Is this what you're after?

  • I changed your title into a h3 (header) tag, because it's a more semantic choice than using a div.

Live Demo #1
Live Demo #2 (with header at top, not sure if you wanted that)

HTML:

<div class="post-container">                
    <div class="post-thumb"><img src="http://dummyimage.com/200x200/f0f/fff" /></div>
    <div class="post-content">
        <h3 class="post-title">Post title</h3>
        <p>post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc post desc </p>
   </div>
</div>

CSS:

.post-container {
    margin: 20px 20px 0 0;  
    border: 5px solid #333;
    overflow: auto
}
.post-thumb {
    float: left
}
.post-thumb img {
    display: block
}
.post-content {
    margin-left: 210px
}
.post-title {
    font-weight: bold;
    font-size: 200%
}

jQuery remove options from select

if your dropdown is in a table and you do not have id for it then you can use the following jquery:

var select_object = purchasing_table.rows[row_index].cells[cell_index].childNodes[1];
$(select_object).find('option[value='+site_name+']').remove();

How to convert a double to long without casting?

If you have a strong suspicion that the DOUBLE is actually a LONG, and you want to

1) get a handle on its EXACT value as a LONG

2) throw an error when its not a LONG

you can try something like this:

public class NumberUtils {

    /**
    * Convert a {@link Double} to a {@link Long}.
    * Method is for {@link Double}s that are actually {@link Long}s and we just
    * want to get a handle on it as one.
    */
    public static long getDoubleAsLong(double specifiedNumber) {
        Assert.isTrue(NumberUtils.isWhole(specifiedNumber));
        Assert.isTrue(specifiedNumber <= Long.MAX_VALUE && specifiedNumber >= Long.MIN_VALUE);
        // we already know its whole and in the Long range
        return Double.valueOf(specifiedNumber).longValue();
    }

    public static boolean isWhole(double specifiedNumber) {
        // http://stackoverflow.com/questions/15963895/how-to-check-if-a-double-value-has-no-decimal-part
        return (specifiedNumber % 1 == 0);
    }
}

Long is a subset of Double, so you might get some strange results if you unknowingly try to convert a Double that is outside of Long's range:

@Test
public void test() throws Exception {
    // Confirm that LONG is a subset of DOUBLE, so numbers outside of the range can be problematic
    Assert.isTrue(Long.MAX_VALUE < Double.MAX_VALUE);
    Assert.isTrue(Long.MIN_VALUE > -Double.MAX_VALUE); // Not Double.MIN_VALUE => read the Javadocs, Double.MIN_VALUE is the smallest POSITIVE double, not the bottom of the range of values that Double can possible be

    // Double.longValue() failure due to being out of range => results are the same even though I minus ten
    System.out.println("Double.valueOf(Double.MAX_VALUE).longValue(): " + Double.valueOf(Double.MAX_VALUE).longValue());
    System.out.println("Double.valueOf(Double.MAX_VALUE - 10).longValue(): " + Double.valueOf(Double.MAX_VALUE - 10).longValue());

    // casting failure due to being out of range => results are the same even though I minus ten
    System.out.println("(long) Double.valueOf(Double.MAX_VALUE): " + (long) Double.valueOf(Double.MAX_VALUE).doubleValue());
    System.out.println("(long) Double.valueOf(Double.MAX_VALUE - 10).longValue(): " + (long) Double.valueOf(Double.MAX_VALUE - 10).doubleValue());
}

What does 'git blame' do?

From GitHub:

The blame command is a Git feature, designed to help you determine who made changes to a file.

Despite its negative-sounding name, git blame is actually pretty innocuous; its primary function is to point out who changed which lines in a file, and why. It can be a useful tool to identify changes in your code.

Basically, git-blame is used to show what revision and author last modified each line of a file. It's like checking the history of the development of a file.