Programs & Examples On #Site mining

How to convert std::chrono::time_point to calendar datetime string with fractional seconds?

Self-explanatory code follows which first creates a std::tm corresponding to 10-10-2012 12:38:40, converts that to a std::chrono::system_clock::time_point, adds 0.123456 seconds, and then prints that out by converting back to a std::tm. How to handle the fractional seconds is in the very last step.

#include <iostream>
#include <chrono>
#include <ctime>

int main()
{
    // Create 10-10-2012 12:38:40 UTC as a std::tm
    std::tm tm = {0};
    tm.tm_sec = 40;
    tm.tm_min = 38;
    tm.tm_hour = 12;
    tm.tm_mday = 10;
    tm.tm_mon = 9;
    tm.tm_year = 112;
    tm.tm_isdst = -1;
    // Convert std::tm to std::time_t (popular extension)
    std::time_t tt = timegm(&tm);
    // Convert std::time_t to std::chrono::system_clock::time_point
    std::chrono::system_clock::time_point tp = 
                                     std::chrono::system_clock::from_time_t(tt);
    // Add 0.123456 seconds
    // This will not compile if std::chrono::system_clock::time_point has
    //   courser resolution than microseconds
    tp += std::chrono::microseconds(123456);
    
    // Now output tp

    // Convert std::chrono::system_clock::time_point to std::time_t
    tt = std::chrono::system_clock::to_time_t(tp);
    // Convert std::time_t to std::tm (popular extension)
    tm = std::tm{0};
    gmtime_r(&tt, &tm);
    // Output month
    std::cout << tm.tm_mon + 1 << '-';
    // Output day
    std::cout << tm.tm_mday << '-';
    // Output year
    std::cout << tm.tm_year+1900 << ' ';
    // Output hour
    if (tm.tm_hour <= 9)
        std::cout << '0';
    std::cout << tm.tm_hour << ':';
    // Output minute
    if (tm.tm_min <= 9)
        std::cout << '0';
    std::cout << tm.tm_min << ':';
    // Output seconds with fraction
    //   This is the heart of the question/answer.
    //   First create a double-based second
    std::chrono::duration<double> sec = tp - 
                                    std::chrono::system_clock::from_time_t(tt) +
                                    std::chrono::seconds(tm.tm_sec);
    //   Then print out that double using whatever format you prefer.
    if (sec.count() < 10)
        std::cout << '0';
    std::cout << std::fixed << sec.count() << '\n';
}

For me this outputs:

10-10-2012 12:38:40.123456

Your std::chrono::system_clock::time_point may or may not be precise enough to hold microseconds.

Update

An easier way is to just use this date library. The code simplifies down to (using C++14 duration literals):

#include "date.h"
#include <iostream>
#include <type_traits>

int
main()
{
    using namespace date;
    using namespace std::chrono;
    auto t = sys_days{10_d/10/2012} + 12h + 38min + 40s + 123456us;
    static_assert(std::is_same<decltype(t),
                               time_point<system_clock, microseconds>>{}, "");
    std::cout << t << '\n';
}

which outputs:

2012-10-10 12:38:40.123456

You can skip the static_assert if you don't need to prove that the type of t is a std::chrono::time_point.

If the output isn't to your liking, for example you would really like dd-mm-yyyy ordering, you could:

#include "date.h"
#include <iomanip>
#include <iostream>

int
main()
{
    using namespace date;
    using namespace std::chrono;
    using namespace std;
    auto t = sys_days{10_d/10/2012} + 12h + 38min + 40s + 123456us;
    auto dp = floor<days>(t);
    auto time = make_time(t-dp);
    auto ymd = year_month_day{dp};
    cout.fill('0');
    cout << ymd.day() << '-' << setw(2) << static_cast<unsigned>(ymd.month())
         << '-' << ymd.year() << ' ' << time << '\n';
}

which gives exactly the requested output:

10-10-2012 12:38:40.123456

Update

Here is how to neatly format the current time UTC with milliseconds precision:

#include "date.h"
#include <iostream>

int
main()
{
    using namespace std::chrono;
    std::cout << date::format("%F %T\n", time_point_cast<milliseconds>(system_clock::now()));
}

which just output for me:

2016-10-17 16:36:02.975

C++17 will allow you to replace time_point_cast<milliseconds> with floor<milliseconds>. Until then date::floor is available in "date.h".

std::cout << date::format("%F %T\n", date::floor<milliseconds>(system_clock::now()));

Update C++20

In C++20 this is now simply:

#include <chrono>
#include <iostream>

int
main()
{
    using namespace std::chrono;
    auto t = sys_days{10d/10/2012} + 12h + 38min + 40s + 123456us;
    std::cout << t << '\n';
}

Or just:

std::cout << std::chrono::system_clock::now() << '\n';

std::format will be available to customize the output.

R barplot Y-axis scale too short

Simplest solution seems to be specifying the ylim range. Here is some code to do this automatically (left default, right - adjusted):

# default y-axis
barplot(dat, beside=TRUE)

# automatically adjusted y-axis
barplot(dat, beside=TRUE, ylim=range(pretty(c(0, dat))))

img

The trick is to use pretty() which returns a list of interval breaks covering all values of the provided data. It guarantees that the maximum returned value is 1) a round number 2) greater than maximum value in the data.

In the example 0 was also added pretty(c(0, dat)) which makes sure that axis starts from 0.

Adb install failure: INSTALL_CANCELED_BY_USER

In addition, any app lock password should be removed by SETTINGS>APP LOCK ,enter the set password and remove the lock. This worked for me on REDMI 4A

Installing PDO driver on MySQL Linux server

At first install necessary PDO parts by running the command

`sudo apt-get install php*-mysql` 

where * is a version name of php like 5.6, 7.0, 7.1, 7.2

After installation you need to mention these two statements

extension=pdo.so
extension=pdo_mysql.so

in your .ini file (uncomment if it is already there) and restart server by command

sudo service apache2 restart

What is the best place for storing uploaded images, SQL database or disk file system?

For security reasons, it is also best practise to avoid problems caused by IE's Content Sniffing which can allow attackers to upload JavaScript inside image files, which might get executed in the context of your site. So you might want to transform the images (crop/resize them) somehow before storing them to prevent this sort of attack. This answer has some other ideas.

jQuery: How can I create a simple overlay?

What do you intend to do with the overlay? If it's static, say, a simple box overlapping some content, just use absolute positioning with CSS. If it's dynamic (I believe this is called a lightbox), you can write some CSS-modifying jQuery code to show/hide the overlay on-demand.

Can I automatically increment the file build version when using Visual Studio?

Each time I do a build it auto-increments the least-significant digit.

I don't have any idea how to update the others, but you should at least be seeing that already...

Func vs. Action vs. Predicate

Action is a delegate (pointer) to a method, that takes zero, one or more input parameters, but does not return anything.

Func is a delegate (pointer) to a method, that takes zero, one or more input parameters, and returns a value (or reference).

Predicate is a special kind of Func often used for comparisons.

Though widely used with Linq, Action and Func are concepts logically independent of Linq. C++ already contained the basic concept in form of typed function pointers.

Here is a small example for Action and Func without using Linq:

class Program
{
    static void Main(string[] args)
    {
        Action<int> myAction = new Action<int>(DoSomething);
        myAction(123);           // Prints out "123"
                                 // can be also called as myAction.Invoke(123);

        Func<int, double> myFunc = new Func<int, double>(CalculateSomething);
        Console.WriteLine(myFunc(5));   // Prints out "2.5"
    }

    static void DoSomething(int i)
    {
        Console.WriteLine(i);
    }

    static double CalculateSomething(int i)
    {
        return (double)i/2;
    }
}

how to create insert new nodes in JsonNode?

These methods are in ObjectNode: the division is such that most read operations are included in JsonNode, but mutations in ObjectNode and ArrayNode.

Note that you can just change first line to be:

ObjectNode jNode = mapper.createObjectNode();
// version ObjectMapper has should return ObjectNode type

or

ObjectNode jNode = (ObjectNode) objectCodec.createObjectNode();
// ObjectCodec is in core part, must be of type JsonNode so need cast

Are table names in MySQL case sensitive?

Database and table names are not case sensitive in Windows, and case sensitive in most varieties of Unix or Linux.

To resolve the issue, set the lower_case_table_names to 1

lower_case_table_names=1

This will make all your tables lowercase, no matter how you write them.

How to do integer division in javascript (Getting division answer in int not float)?

var answer = Math.floor(x)

I sincerely hope this will help future searchers when googling for this common question.

Twitter Bootstrap: div in container with 100% height

It is very simple. You can use

.fill .map 
{
  min-height: 100vh;
}

You can change height according to your requirement.

Initial size for the ArrayList

My two cents on Stream. I think it's better to use

IntStream.generate(i -> MyClass.contruct())
         .limit(INT_SIZE)
         .collect(Collectors.toList());

with the flexibility to put any initial values.

Creating an array of objects in Java

Yes it is correct in Java there are several steps to make an array of objects:

  1. Declaring and then Instantiating (Create memory to store '4' objects):

    A[ ] arr = new A[4];
    
  2. Initializing the Objects (In this case you can Initialize 4 objects of class A)

    arr[0] = new A();
    arr[1] = new A();
    arr[2] = new A();
    arr[3] = new A();
    

    or

    for( int i=0; i<4; i++ )
      arr[i] = new A();
    

Now you can start calling existing methods from the objects you just made etc.

For example:

  int x = arr[1].getNumber();

or

  arr[1].setNumber(x);

Getting the difference between two repositories

Meld can compare directories:

meld directory1 directory2

Just use the directories of the two git repos and you will get a nice graphical comparison:

enter image description here

When you click on one of the blue items, you can see what changed.

bash: pip: command not found

It solved my problem by using

sudo easy_install pip

Where is shared_ptr?

If your'e looking bor boost's shared_ptr, you could have easily found the answer by googling shared_ptr, following the links to the docs, and pulling up a complete working example such as this.

In any case, here is a minimalistic complete working example for you which I just hacked up:

#include <boost/shared_ptr.hpp>

struct MyGizmo
{
    int n_;
};

int main()
{
    boost::shared_ptr<MyGizmo> p(new MyGizmo);
    return 0;
}

In order for the #include to find the header, the libraries obviously need to be in the search path. In MSVC, you set this in Project Settings>Configuration Properties>C/C++>Additional Include Directories. In my case, this is set to C:\Program Files (x86)\boost\boost_1_42

Can (a== 1 && a ==2 && a==3) ever evaluate to true?

Rule number one of interviews; never say impossible.

No need for hidden character trickery.

_x000D_
_x000D_
window.__defineGetter__( 'a', function(){_x000D_
    if( typeof i !== 'number' ){_x000D_
        // define i in the global namespace so that it's not lost after this function runs_x000D_
        i = 0;_x000D_
    }_x000D_
    return ++i;_x000D_
});_x000D_
_x000D_
if( a == 1 && a == 2 && a == 3 ){_x000D_
    alert( 'Oh dear, what have we done?' );_x000D_
}
_x000D_
_x000D_
_x000D_

Pandas: Convert Timestamp to datetime.date

Use the .date method:

In [11]: t = pd.Timestamp('2013-12-25 00:00:00')

In [12]: t.date()
Out[12]: datetime.date(2013, 12, 25)

In [13]: t.date() == datetime.date(2013, 12, 25)
Out[13]: True

To compare against a DatetimeIndex (i.e. an array of Timestamps), you'll want to do it the other way around:

In [21]: pd.Timestamp(datetime.date(2013, 12, 25))
Out[21]: Timestamp('2013-12-25 00:00:00')

In [22]: ts = pd.DatetimeIndex([t])

In [23]: ts == pd.Timestamp(datetime.date(2013, 12, 25))
Out[23]: array([ True], dtype=bool)

Could not find default endpoint element

Unit testing a non-library application that consumes a service can cause this problem.

The information that others have entered addresses the root cause of this. If you are trying to write automated test cases and the unit you are testing will actually invoke the service interface, you need to add the service reference to the test project. This is a flavor of the application using library type of error. I did not immediately realize this though because my code that consumes the interface is not in a library. However, when the test actually runs it will be running from the test assembly, not the assembly under test.

Adding a service reference to the unit test project resolved my issue.

Laravel password validation rule

This doesn't quite match the OP requirements, though hopefully it helps. With Laravel you can define your rules in an easy-to-maintain format like so:

    $inputs = [
        'email'    => 'foo',
        'password' => 'bar',
    ];

    $rules = [
        'email'    => 'required|email',
        'password' => [
            'required',
            'string',
            'min:10',             // must be at least 10 characters in length
            'regex:/[a-z]/',      // must contain at least one lowercase letter
            'regex:/[A-Z]/',      // must contain at least one uppercase letter
            'regex:/[0-9]/',      // must contain at least one digit
            'regex:/[@$!%*#?&]/', // must contain a special character
        ],
    ];

    $validation = \Validator::make( $inputs, $rules );

    if ( $validation->fails() ) {
        print_r( $validation->errors()->all() );
    }

Would output:

    [
        'The email must be a valid email address.',
        'The password must be at least 10 characters.',
        'The password format is invalid.',
    ]

(The regex rules share an error message by default—i.e. four failing regex rules result in one error message)

Using CSS in Laravel views?

We can do this by the following way.

<link href="{{ asset('/css/style.css') }}" rel="stylesheet">

{{ HTML::style('css/style.css', array('media' => 'print')) }}

It will search the style file in the public folder of Laravel and then will render it.

IntelliJ IDEA generating serialVersionUID

If you want to add the absent serialVersionUID for a bunch of files, IntelliJ IDEA may not work very well. I come up some simple script to fulfill this goal with ease:

base_dir=$(pwd)
src_dir=$base_dir/src/main/java
ic_api_cp=$base_dir/target/classes

while read f
do
    clazz=${f//\//.}
    clazz=${clazz/%.java/}
    seruidstr=$(serialver -classpath $ic_api_cp $clazz | cut -d ':' -f 2 | sed -e 's/^\s\+//')
    perl -ni.bak -e "print $_; printf qq{%s\n}, q{    private $seruidstr} if /public class/" $src_dir/$f
done

You save this script, say as add_serialVersionUID.sh in your ~/bin folder. Then you run it in the root directory of your Maven or Gradle project like:

add_serialVersionUID.sh < myJavaToAmend.lst

This .lst includes the list of Java files to add the serialVersionUID in the following format:

com/abc/ic/api/model/domain/item/BizOrderTransDO.java
com/abc/ic/api/model/domain/item/CardPassFeature.java
com/abc/ic/api/model/domain/item/CategoryFeature.java
com/abc/ic/api/model/domain/item/GoodsFeature.java
com/abc/ic/api/model/domain/item/ItemFeature.java
com/abc/ic/api/model/domain/item/ItemPicUrls.java
com/abc/ic/api/model/domain/item/ItemSkuDO.java
com/abc/ic/api/model/domain/serve/ServeCategoryFeature.java
com/abc/ic/api/model/domain/serve/ServeFeature.java
com/abc/ic/api/model/param/depot/DepotItemDTO.java
com/abc/ic/api/model/param/depot/DepotItemQueryDTO.java
com/abc/ic/api/model/param/depot/InDepotDTO.java
com/abc/ic/api/model/param/depot/OutDepotDTO.java

This script uses the JDK serialVer tool. It is ideal for a situation when you want to amend a huge number of classes which had no serialVersionUID set in the first place while maintain the compatibility with the old classes.

Foreign Key to non-primary key

As others have pointed out, ideally, the foreign key would be created as a reference to a primary key (usually an IDENTITY column). However, we don't live in an ideal world, and sometimes even a "small" change to a schema can have significant ripple effects to the application logic.

Consider the case of a Customer table with a SSN column (and a dumb primary key), and a Claim table that also contains a SSN column (populated by business logic from the Customer data, but no FK exists). The design is flawed, but has been in use for several years, and three different applications have been built on the schema. It should be obvious that ripping out Claim.SSN and putting in a real PK-FK relationship would be ideal, but would also be a significant overhaul. On the other hand, putting a UNIQUE constraint on Customer.SSN, and adding a FK on Claim.SSN, could provide referential integrity, with little or no impact on the applications.

Don't get me wrong, I'm all for normalization, but sometimes pragmatism wins over idealism. If a mediocre design can be helped with a band-aid, surgery might be avoided.

Python: Find index of minimum item in list of floats

Use of the argmin method for numpy arrays.

import numpy as np
np.argmin(myList)

However, it is not the fastest method: it is 3 times slower than OP's answer on my computer. It may be the most concise one though.

Cannot set property 'display' of undefined

document.getElementsByClassName('btn-pageMenu') delivers a nodeList. You should use: document.getElementsByClassName('btn-pageMenu')[0].style.display (if it's the first element from that list you want to change.

If you want to change style.display for all nodes loop through the list:

var elems = document.getElementsByClassName('btn-pageMenu');
for (var i=0;i<elems.length;i+=1){
  elems[i].style.display = 'block';
}

to be complete: if you use jquery it is as simple as:

?$('.btn-pageMenu').css('display'???????????????????????????,'block');??????

How to add hyperlink in JLabel?

If <a href="link"> doesn't work, then:

  1. Create a JLabel and add a MouseListener (decorate the label to look like a hyperlink)
  2. Implement mouseClicked() event
  3. In the implementation of mouseClicked() event, perform your action

Have a look at java.awt.Desktop API for opening a link using the default browser (this API is available only from Java6).

Reliable way to convert a file to a byte[]

Others have noted that you can use the built-in File.ReadAllBytes. The built-in method is fine, but it's worth noting that the code you post above is fragile for two reasons:

  1. Stream is IDisposable - you should place the FileStream fs = new FileStream(filename, FileMode.Open,FileAccess.Read) initialization in a using clause to ensure the file is closed. Failure to do this may mean that the stream remains open if a failure occurs, which will mean the file remains locked - and that can cause other problems later on.
  2. fs.Read may read fewer bytes than you request. In general, the .Read method of a Stream instance will read at least one byte, but not necessarily all bytes you ask for. You'll need to write a loop that retries reading until all bytes are read. This page explains this in more detail.

How to get the PID of a process by giving the process name in Mac OS X ?

Try this one:

echo "$(ps -ceo pid=,comm= | awk '/firefox/ { print $1; exit }')"

The ps command produces output like this, with the PID in the first column and the executable name (only) in the second column:

bookworm% ps -ceo pid=,comm=
    1 launchd
   10 kextd
   11 UserEventAgent
   12 mDNSResponder
   13 opendirectoryd
   14 notifyd
   15 configd

...which awk processes, printing the first column (pid) and exiting after the first match.

Java HashMap: How to get a key and value by index?

Here is the general solution if you really only want the first key's value

Object firstKey = myHashMap.keySet().toArray()[0];
Object valueForFirstKey = myHashMap.get(firstKey);

Execution sequence of Group By, Having and Where clause in SQL Server?

Having Clause may come prior/before the group by clause.

Example: select * FROM test_std; ROLL_NO SNAME DOB TEACH


     1 John       27-AUG-18 Wills     
     2 Knit       27-AUG-18 Prestion  
     3 Perl       27-AUG-18 Wills     
     4 Ohrm       27-AUG-18 Woods     
     5 Smith      27-AUG-18 Charmy    
     6 Jony       27-AUG-18 Wills     
       Warner     20-NOV-18 Wills     
       Marsh      12-NOV-18 Langer    
       FINCH      18-OCT-18 Langer    

9 rows selected.

select teach, count() count from test_std having count() > 1 group by TEACH ;

TEACH COUNT


Langer 2 Wills 4

Is there any way to have a fieldset width only be as wide as the controls in them?

            <table style="position: relative; top: -0px; left: 0px;">
                <tr>
                    <td>
                        <div>   
                            <fieldset style="width:0px">
                                <legend>A legend</legend>
                                <br/>
                                <table cellspacing="0" align="left">
                                    <tbody>
                                        <tr>
                                            <td align='left' style="white-space: nowrap;">
                                            </td>
                                        </tr>
                                    </tbody>
                                </table>
                            </fieldset>
                        </div>
                    </td>
                </tr>
            </table>

How do you use the Immediate Window in Visual Studio?

The Immediate window is used to debug and evaluate expressions, execute statements, print variable values, and so forth. It allows you to enter expressions to be evaluated or executed by the development language during debugging.

To display Immediate Window, choose Debug >Windows >Immediate or press Ctrl-Alt-I

enter image description here

Here is an example with Immediate Window:

int Sum(int x, int y) { return (x + y);}
void main(){
int a, b, c;
a = 5;
b = 7;
c = Sum(a, b);
char temp = getchar();}

add breakpoint

enter image description here

call commands

enter image description here

https://msdn.microsoft.com/en-us/library/f177hahy.aspx

css with background image without repeating the image

Instead of

background-repeat-x: no-repeat;
background-repeat-y: no-repeat;

which is not correct, use

background-repeat: no-repeat;

How to get GET (query string) variables in Express.js on Node.js?

I am using MEANJS 0.6.0 with [email protected], it's good

Client:

Controller:

var input = { keyword: vm.keyword };
ProductAPi.getOrder(input)

services:

this.getOrder = function (input) {return $http.get('/api/order', { params: input });};

Server

routes

app.route('/api/order').get(products.order);

controller

exports.order = function (req, res) {
  var keyword = req.query.keyword
  ...

Collision resolution in Java HashMap

In a HashMap the key is an object, that contains hashCode() and equals(Object) methods.

When you insert a new entry into the Map, it checks whether the hashCode is already known. Then, it will iterate through all objects with this hashcode, and test their equality with .equals(). If an equal object is found, the new value replaces the old one. If not, it will create a new entry in the map.

Usually, talking about maps, you use collision when two objects have the same hashCode but they are different. They are internally stored in a list.

What does "implements" do on a class?

Interfaces are implemented through classes. They are purely abstract classes, if you will.

In PHP when a class implements from an interface, the methods defined in that interface are to be strictly followed. When a class inherits from a parent class, method parameters may be altered. That is not the case for interfaces:

interface ImplementMeStrictly {
   public function foo($a, $b);
}

class Obedient implements ImplementMeStrictly {
   public function foo($a, $b, $c) 
      {
      }
}

will cause an error, because the interface wasn't implemented as defined. Whereas:

class InheritMeLoosely {
   public function foo($a)
      {
      }
}

class IDoWhateverWithFoo extends InheritMeLoosely {
   public function foo()
      {
      }
}

Is allowed.

Array or List in Java. Which is faster?

Arrays recommended everywhere you may use them instead of list, especially in case if you know items count and size would not be changing.

See Oracle Java best practice: http://docs.oracle.com/cd/A97688_16/generic.903/bp/java.htm#1007056

Of course, if you need add and remove objects from collection many times easy use lists.

The object 'DF__*' is dependent on column '*' - Changing int to double

When we try to drop a column which is depended upon then we see this kind of error:

The object 'DF__*' is dependent on column ''.

drop the constraint which is dependent on that column with:

ALTER TABLE TableName DROP CONSTRAINT dependent_constraint;

Example:

Msg 5074, Level 16, State 1, Line 1

The object 'DF__Employees__Colf__1273C1CD' is dependent on column 'Colf'.

Msg 4922, Level 16, State 9, Line 1

ALTER TABLE DROP COLUMN Colf failed because one or more objects access this column.

Drop Constraint(DF__Employees__Colf__1273C1CD):

ALTER TABLE Employees DROP CONSTRAINT DF__Employees__Colf__1273C1CD;

Then you can Drop Column:

Alter Table TableName Drop column ColumnName

How to vertically center a container in Bootstrap?

The Flexible box way

Vertical alignment is now very simple by the use of Flexible box layout. Nowadays, this method is supported in a wide range of web browsers except Internet Explorer 8 & 9. Therefore we'd need to use some hacks/polyfills or different approaches for IE8/9.

In the following I'll show you how to do that in only 3 lines of text (regardless of old flexbox syntax).

Note: it's better to use an additional class instead of altering .jumbotron to achieve the vertical alignment. I'd use vertical-center class name for instance.

Example Here (A Mirror on jsbin).

<div class="jumbotron vertical-center"> <!-- 
                      ^--- Added class  -->
  <div class="container">
    ...
  </div>
</div>
.vertical-center {
  min-height: 100%;  /* Fallback for browsers do NOT support vh unit */
  min-height: 100vh; /* These two lines are counted as one :-)       */

  display: flex;
  align-items: center;
}

Important notes (Considered in the demo):

  1. A percentage values of height or min-height properties is relative to the height of the parent element, therefore you should specify the height of the parent explicitly.

  2. Vendor prefixed / old flexbox syntax omitted in the posted snippet due to brevity, but exist in the online example.

  3. In some of old web browsers such as Firefox 9 (in which I've tested), the flex container - .vertical-center in this case - won't take the available space inside the parent, therefore we need to specify the width property like: width: 100%.

  4. Also in some of web browsers as mentioned above, the flex item - .container in this case - may not appear at the center horizontally. It seems the applied left/right margin of auto doesn't have any effect on the flex item.
    Therefore we need to align it by box-pack / justify-content.

For further details and/or vertical alignment of columns, you could refer to the topic below:


The traditional way for legacy web browsers

This is the old answer I wrote at the time I answered this question. This method has been discussed here and it's supposed to work in Internet Explorer 8 and 9 as well. I'll explain it in short:

In inline flow, an inline level element can be aligned vertically to the middle by vertical-align: middle declaration. Spec from W3C:

middle
Align the vertical midpoint of the box with the baseline of the parent box plus half the x-height of the parent.

In cases that the parent - .vertical-center element in this case - has an explicit height, by any chance if we could have a child element having the exact same height of the parent, we would be able to move the baseline of the parent to the midpoint of the full-height child and surprisingly make our desired in-flow child - the .container - aligned to the center vertically.

Getting all together

That being said, we could create a full-height element within the .vertical-center by ::before or ::after pseudo elements and also change the default display type of it and the other child, the .container to inline-block.

Then use vertical-align: middle; to align the inline elements vertically.

Here you go:

<div class="jumbotron vertical-center">
  <div class="container">
    ...
  </div>
</div>
.vertical-center {
  height:100%;
  width:100%;

  text-align: center;  /* align the inline(-block) elements horizontally */
  font: 0/0 a;         /* remove the gap between inline(-block) elements */
}

.vertical-center:before {    /* create a full-height inline block pseudo=element */
  content: " ";
  display: inline-block;
  vertical-align: middle;    /* vertical alignment of the inline element */
  height: 100%;
}

.vertical-center > .container {
  max-width: 100%;

  display: inline-block;
  vertical-align: middle;  /* vertical alignment of the inline element */
                           /* reset the font property */
  font: 16px/1 "Helvetica Neue", Helvetica, Arial, sans-serif;
}

WORKING DEMO.

Also, to prevent unexpected issues in extra small screens, you can reset the height of the pseudo-element to auto or 0 or change its display type to none if needed so:

@media (max-width: 768px) {
  .vertical-center:before {
    height: auto;
    /* Or */
    display: none;
  }
}

UPDATED DEMO

And one more thing:

If there are footer/header sections around the container, it's better to position that elements properly (relative, absolute? up to you.) and add a higher z-index value (for assurance) to keep them always on the top of the others.

CURL to pass SSL certifcate and password

Addition to previous answer make sure that your curl installation supports https.
You can use curl --version to get information about supported protocols.

If your curl supports https follow the previous answer.

curl --cert certificate_path:password https://www.example.com

If it does not support https, you need to install a cURL version that supports https.

List of Java processes

Starting from Java 7, the simplest way and less error prone is to simply use the command jcmd that is part of the JDK such that it will work the same way on all OS.

Example:

> jcmd
5485 sun.tools.jcmd.JCmd
2125 MyProgram

jcmd allows to send diagnostic command requests to a running Java Virtual Machine (JVM).

More details about how to use jcmd.

See also the jcmd Utility

How to list only files and not directories of a directory Bash?

find files: ls -l /home | grep "^-" | tr -s ' ' | cut -d ' ' -f 9

find directories: ls -l /home | grep "^d" | tr -s ' ' | cut -d ' ' -f 9

find links: ls -l /home | grep "^l" | tr -s ' ' | cut -d ' ' -f 9

tr -s ' ' turns the output into a space-delimited file the cut command says the delimiter is a space, and return the 9th field (always the filename/directory name/linkname).

I use this all the time!

Javascript change date into format of (dd/mm/yyyy)

This will ensure you get a two-digit day and month.

function formattedDate(d = new Date) {
  let month = String(d.getMonth() + 1);
  let day = String(d.getDate());
  const year = String(d.getFullYear());

  if (month.length < 2) month = '0' + month;
  if (day.length < 2) day = '0' + day;

  return `${day}/${month}/${year}`;
}

Or terser:

function formattedDate(d = new Date) {
  return [d.getDate(), d.getMonth()+1, d.getFullYear()]
      .map(n => n < 10 ? `0${n}` : `${n}`).join('/');
}

How do I programmatically "restart" an Android app?

I had to add a Handler to delay the exit:

 mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 200, mPendingIntent);
        final Handler handler = new Handler();
        handler.postDelayed(new Runnable() {
            @Override
            public void run() {
                Runtime.getRuntime().exit(0);
            }
        }, 100);

Pass connection string to code-first DbContext

After reading the docs, I have to pass the name of the connection string instead:

var db = new NerdDinners("NerdDinnerDb");

The difference between "require(x)" and "import x"

Not an answer here and more like a comment, sorry but I can't comment.

In node V10, you can use the flag --experimental-modules to tell Nodejs you want to use import. But your entry script should end with .mjs.

Note this is still an experimental thing and should not be used in production.

// main.mjs
import utils from './utils.js'
utils.print();
// utils.js
module.exports={
    print:function(){console.log('print called')}
}

Ref 1 - Nodejs Doc

Ref 2 - github issue

Rotating and spacing axis labels in ggplot2

I'd like to provide an alternate solution, a robust solution similar to what I am about to propose was required in the latest version of ggtern, since introducing the canvas rotation feature.

Basically, you need to determine the relative positions using trigonometry, by building a function which returns an element_text object, given angle (ie degrees) and positioning (ie one of x,y,top or right) information.

#Load Required Libraries
library(ggplot2)
library(gridExtra)

#Build Function to Return Element Text Object
rotatedAxisElementText = function(angle,position='x'){
  angle     = angle[1]; 
  position  = position[1]
  positions = list(x=0,y=90,top=180,right=270)
  if(!position %in% names(positions))
    stop(sprintf("'position' must be one of [%s]",paste(names(positions),collapse=", ")),call.=FALSE)
  if(!is.numeric(angle))
    stop("'angle' must be numeric",call.=FALSE)
  rads  = (angle - positions[[ position ]])*pi/180
  hjust = 0.5*(1 - sin(rads))
  vjust = 0.5*(1 + cos(rads))
  element_text(angle=angle,vjust=vjust,hjust=hjust)
}

Frankly, in my opinion, I think that an 'auto' option should be made available in ggplot2 for the hjust and vjust arguments, when specifying the angle, anyway, lets demonstrate how the above works.

#Demonstrate Usage for a Variety of Rotations
df    = data.frame(x=0.5,y=0.5)
plots = lapply(seq(0,90,length.out=4),function(a){
  ggplot(df,aes(x,y)) + 
    geom_point() + 
    theme(axis.text.x = rotatedAxisElementText(a,'x'),
          axis.text.y = rotatedAxisElementText(a,'y')) +
    labs(title = sprintf("Rotated %s",a))
})
grid.arrange(grobs=plots)

Which produces the following:

Example

Difference between "\n" and Environment.NewLine

Exact implementation of Environment.NewLine from the source code:

The implementation in .NET 4.6.1:

/*===================================NewLine====================================
**Action: A property which returns the appropriate newline string for the given
**        platform.
**Returns: \r\n on Win32.
**Arguments: None.
**Exceptions: None.
==============================================================================*/
public static String NewLine {
    get {
        Contract.Ensures(Contract.Result<String>() != null);
        return "\r\n";
    }
}

source


The implementation in .NET Core:

/*===================================NewLine====================================
**Action: A property which returns the appropriate newline string for the
**        given platform.
**Returns: \r\n on Win32.
**Arguments: None.
**Exceptions: None.
==============================================================================*/
public static String NewLine {
    get {
        Contract.Ensures(Contract.Result() != null);
#if !PLATFORM_UNIX
        return "\r\n";
#else
        return "\n";
#endif // !PLATFORM_UNIX
    }
}

source (in System.Private.CoreLib)

public static string NewLine => "\r\n";

source (in System.Runtime.Extensions)

How to convert int to Integer

As mentioned, one way is to use

new Integer(my_int_value)

But you should not call the constructor for wrapper classes directly

So, modify the code accordingly:

mBitmapCache.put(Integer.valueOf(R.drawable.bg1),object);

Excel VBA to Export Selected Sheets to PDF

Once you have Selected a group of sheets, you can use Selection

Consider:

Sub luxation()
    ThisWorkbook.Sheets(Array("Sheet1", "Sheet2", "Sheet3")).Select
    Selection.ExportAsFixedFormat _
        Type:=xlTypePDF, _
        Filename:="C:\TestFolder\temp.pdf", _
        Quality:=xlQualityStandard, _
        IncludeDocProperties:=True, _
        IgnorePrintAreas:=False, _
        OpenAfterPublish:=True
End Sub

EDIT#1:

Further testing has reveled that this technique depends on the group of cells selected on each worksheet. To get a comprehensive output, use something like:

Sub Macro1()

   Sheets("Sheet1").Activate
   ActiveSheet.UsedRange.Select
   Sheets("Sheet2").Activate
   ActiveSheet.UsedRange.Select
   Sheets("Sheet3").Activate
   ActiveSheet.UsedRange.Select

   ThisWorkbook.Sheets(Array("Sheet1", "Sheet2", "Sheet3")).Select
   Selection.ExportAsFixedFormat Type:=xlTypePDF, Filename:= _
      "C:\Users\James\Desktop\pdfmaker.pdf", Quality:=xlQualityStandard, _
      IncludeDocProperties:=True, IgnorePrintAreas:=False, OpenAfterPublish:= _
      True
End Sub

What's the difference between equal?, eql?, ===, and ==?

I'm going to heavily quote the Object documentation here, because I think it has some great explanations. I encourage you to read it, and also the documentation for these methods as they're overridden in other classes, like String.

Side note: if you want to try these out for yourself on different objects, use something like this:

class Object
  def all_equals(o)
    ops = [:==, :===, :eql?, :equal?]
    Hash[ops.map(&:to_s).zip(ops.map {|s| send(s, o) })]
  end
end

"a".all_equals "a" # => {"=="=>true, "==="=>true, "eql?"=>true, "equal?"=>false}

== — generic "equality"

At the Object level, == returns true only if obj and other are the same object. Typically, this method is overridden in descendant classes to provide class-specific meaning.

This is the most common comparison, and thus the most fundamental place where you (as the author of a class) get to decide if two objects are "equal" or not.

=== — case equality

For class Object, effectively the same as calling #==, but typically overridden by descendants to provide meaningful semantics in case statements.

This is incredibly useful. Examples of things which have interesting === implementations:

  • Range
  • Regex
  • Proc (in Ruby 1.9)

So you can do things like:

case some_object
when /a regex/
  # The regex matches
when 2..4
  # some_object is in the range 2..4
when lambda {|x| some_crazy_custom_predicate }
  # the lambda returned true
end

See my answer here for a neat example of how case+Regex can make code a lot cleaner. And of course, by providing your own === implementation, you can get custom case semantics.

eql?Hash equality

The eql? method returns true if obj and other refer to the same hash key. This is used by Hash to test members for equality. For objects of class Object, eql? is synonymous with ==. Subclasses normally continue this tradition by aliasing eql? to their overridden == method, but there are exceptions. Numeric types, for example, perform type conversion across ==, but not across eql?, so:

1 == 1.0     #=> true
1.eql? 1.0   #=> false

So you're free to override this for your own uses, or you can override == and use alias :eql? :== so the two methods behave the same way.

equal? — identity comparison

Unlike ==, the equal? method should never be overridden by subclasses: it is used to determine object identity (that is, a.equal?(b) iff a is the same object as b).

This is effectively pointer comparison.

self.tableView.reloadData() not working in Swift

In my case the table was updated correctly, but setNeedDisplay() was not called for the image so I mistakenly thought that the data was not reloaded.

Angular - Can't make ng-repeat orderBy work

Here's a version of @Julian Mosquera's code that also supports a "fallback" field to use in case the primary field happens to be null or undefined:

yourApp.filter('orderObjectBy', function() {
  return function(items, field, fallback, reverse) {
    var filtered = [];
    angular.forEach(items, function(item) {
      filtered.push(item);
    });
    filtered.sort(function (a, b) {
      var af = a[field];
      if(af === undefined || af === null) { af = a[fallback]; }

      var bf = b[field];
      if(bf === undefined || bf === null) { bf = b[fallback]; }

      return (af > bf ? 1 : -1);
    });
    if(reverse) filtered.reverse();
    return filtered;
  };
});

Remove all the elements that occur in one list from another

Sets versus list comprehension benchmark on Python 3.8

(adding up to Moinuddin Quadri's benchmarks)

tldr: Use Arkku's set solution, it's even faster than promised in comparison!

Checking existing files against a list

In my example I found it to be 40 times (!) faster to use Arkku's set solution than the pythonic list comprehension for a real world application of checking existing filenames against a list.

List comprehension:

%%time
import glob
existing = [int(os.path.basename(x).split(".")[0]) for x in glob.glob("*.txt")]
wanted = list(range(1, 100000))
[i for i in wanted if i not in existing]

Wall time: 28.2 s

Sets

%%time
import glob
existing = [int(os.path.basename(x).split(".")[0]) for x in glob.glob("*.txt")]
wanted = list(range(1, 100000))
set(wanted) - set(existing)

Wall time: 689 ms

Security of REST authentication schemes

If you require the hash of the body as one of the parameters in the URL and that URL is signed via a private key, then a man-in-the-middle attack would only be able to replace the body with content that would generate the same hash. Easy to do with MD5 hash values now at least and when SHA-1 is broken, well, you get the picture.

To secure the body from tampering, you would need to require a signature of the body, which a man-in-the-middle attack would be less likely to be able to break since they wouldn't know the private key that generates the signature.

Open URL in Java to get the content

It may be more useful to use a http client library like such as this

There are more things like access denied , document moved etc to handle when dealing with http.

(though, it is unlikely in this case)

Adding a background image to a <div> element

You mean this?

<style type="text/css">
.bgimg {
    background-image: url('../images/divbg.png');
}
</style>

...

<div class="bgimg">
    div with background
</div>

ERROR 2006 (HY000): MySQL server has gone away

For amazon RDS (it's my case), you can change the max_allowed_packet parameter value to any numeric value in bytes that makes sense for the biggest data in any insert you may have (e.g.: if you have some 50mb blob values in your insert, set the max_allowed_packet to 64M = 67108864), in a new or existing parameter-group. Then apply that parameter-group to your MySQL instance (may require rebooting the instance).

PHP Using RegEx to get substring of a string

$string = "producturl.php?id=736375493?=tm";
$number = preg_replace("/[^0-9]/", '', $string);

Bootstrap 3: Offset isn't working?

Which version of bootstrap are you using? The early versions of Bootstrap 3 (3.0, 3.0.1) didn't work with this functionality.

col-md-offset-0 should be working as seen in this bootstrap example found here (http://getbootstrap.com/css/#grid-responsive-resets):

<div class="row">
   <div class="col-sm-5 col-md-6">.col-sm-5 .col-md-6</div>
   <div class="col-sm-5 col-sm-offset-2 col-md-6 col-md-offset-0">.col-sm-5 .col-sm-offset-2 .col-md-6 .col-md-offset-0</div>
</div>

Is it possible to disable the network in iOS Simulator?

If your app is connecting to a specific domain, you can simply add it to your /etc/hosts file and route it to a non-existing IP in your local network... For the application it will be the same as if there was no internet connection or the server is not reachable.

sudo nano /etc/hosts

add the following line:

192.168.1.123   example.com

or use 127.0.0.1 if you are not running a webserver on your local machine.

Angular 2 Routing run in new tab

This seems a little confused.

Opening your application in another window or tab will require your entire application to be re-bootstrapped, and then for your router to... pick up that url, convert it into a route, and load the appropriate component.

This is exactly what will happen if you just use a link instead. In fact, that's all that's happening.

The point of the router is to swap components in and out of your router-outlet, which is something that's been bootstrapped and exists within the confines of your running application and isn't shared across multiple windows.

Access props inside quotes in React JSX

For People, looking for answers w.r.t to 'map' function and dynamic data, here is a working example.

<img src={"http://examole.com/randomview/images" + each_actor['logo']} />

This gives the URL as "http://examole.com/randomview/images/2/dp_pics/182328.jpg" (random example)

JPA OneToMany and ManyToOne throw: Repeated column in mapping for entity column (should be mapped with insert="false" update="false")

I am not really sure about your question (the meaning of "empty table" etc, or how mappedBy and JoinColumn were not working).

I think you were trying to do a bi-directional relationships.

First, you need to decide which side "owns" the relationship. Hibernate is going to setup the relationship base on that side. For example, assume I make the Post side own the relationship (I am simplifying your example, just to keep things in point), the mapping will look like:

(Wish the syntax is correct. I am writing them just by memory. However the idea should be fine)

public class User{
    @OneToMany(fetch=FetchType.LAZY, cascade = CascadeType.ALL, mappedBy="user")
    private List<Post> posts;
}


public class Post {
    @ManyToOne(fetch=FetchType.LAZY)
    @JoinColumn(name="user_id")
    private User user;
}

By doing so, the table for Post will have a column user_id which store the relationship. Hibernate is getting the relationship by the user in Post (Instead of posts in User. You will notice the difference if you have Post's user but missing User's posts).

You have mentioned mappedBy and JoinColumn is not working. However, I believe this is in fact the correct way. Please tell if this approach is not working for you, and give us a bit more info on the problem. I believe the problem is due to something else.


Edit:

Just a bit extra information on the use of mappedBy as it is usually confusing at first. In mappedBy, we put the "property name" in the opposite side of the bidirectional relationship, not table column name.

How to encode URL parameters?

With urlsearchparams:

const params = new URLSearchParams()
params.append('imageurl', http://www.image.com/?username=unknown&password=unknown)
return `http://www.foobar.com/foo?${params.toString()}`

Android adding simple animations while setvisibility(view.Gone)

The easiest way to animate Visibility changes is use Transition API which available in support (androidx) package. Just call TransitionManager.beginDelayedTransition method then change visibility of the view. There are several default transitions like Fade, Slide.

import androidx.transition.TransitionManager;
import androidx.transition.Transition;
import androidx.transition.Fade;

private void toggle() {
    Transition transition = new Fade();
    transition.setDuration(600);
    transition.addTarget(R.id.image);

    TransitionManager.beginDelayedTransition(parent, transition);
    image.setVisibility(show ? View.VISIBLE : View.GONE);
}

Where parent is parent ViewGroup of animated view. Result:

enter image description here

Here is result with Slide transition:

import androidx.transition.Slide;

Transition transition = new Slide(Gravity.BOTTOM);

enter image description here

It is easy to write custom transition if you need something different. Here is example with CircularRevealTransition which I wrote in another answer. It shows and hide view with CircularReveal animation.

Transition transition = new CircularRevealTransition();

enter image description here

android:animateLayoutChanges="true" option does same thing, it just uses AutoTransition as transition.

How to detect when cancel is clicked on file input?

Shiboe's solution would be a good one if it worked on mobile webkit, but it doesn't. What I can come up with is to add a mousemove event listener to some dom object at the time that the file input window is opened, like so:

 $('.upload-progress').mousemove(function() {
        checkForFiles(this);
      });
      checkForFiles = function(me) {
        var filefield = $('#myfileinput');
        var files = filefield.get(0).files;
        if (files == undefined || files[0] == undefined) $(me).remove(); // user cancelled the upload
      };

The mousemove event is blocked from the page while the file dialog is open, and when its closed one checks to see if there are any files in the file input. In my case I want an activity indicator blocking things till the file is uploaded, so I only want to remove my indicator on cancel.

However this doesn't solve for mobile, since there is no mouse to move. My solution there is less than perfect, but I think its good enough.

       $('.upload-progress').bind('touchstart', function() {
        checkForFiles(this);
      });

Now we're listening for a touch on the screen to do the same files check. I'm pretty confident that the user's finger will be put on the screen pretty quickly after cancel and dismiss this activity indicator.

One could also just add the activity indicator on the file input change event, but on mobile there is often a few seconds lag between selecting the image and the change event firing, so its just much better UX for the activity indicator to be displayed at the start of the process.

Excel 2007 - Compare 2 columns, find matching values

=VLOOKUP(lookup_value,table_array,col_index_num,range_lookup) will solve this issue.

This will search for a value in the first column to the left and return the value in the same row from a specific column.

Plot bar graph from Pandas DataFrame

To plot just a selection of your columns you can select the columns of interest by passing a list to the subscript operator:

ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)

What you tried was df['V1','V2'] this will raise a KeyError as correctly no column exists with that label, although it looks funny at first you have to consider that your are passing a list hence the double square brackets [[]].

import matplotlib.pyplot as plt
ax = df[['V1','V2']].plot(kind='bar', title ="V comp", figsize=(15, 10), legend=True, fontsize=12)
ax.set_xlabel("Hour", fontsize=12)
ax.set_ylabel("V", fontsize=12)
plt.show()

enter image description here

Get the _id of inserted document in Mongo database in NodeJS

A shorter way than using second parameter for the callback of collection.insert would be using objectToInsert._id that returns the _id (inside of the callback function, supposing it was a successful operation).

The Mongo driver for NodeJS appends the _id field to the original object reference, so it's easy to get the inserted id using the original object:

collection.insert(objectToInsert, function(err){
   if (err) return;
   // Object inserted successfully.
   var objectId = objectToInsert._id; // this will return the id of object inserted
});

Mark error in form using Bootstrap

Generally showing the error near where the error occurs is best. i.e. if someone has an error with entering their email, you highlight the email input box.

This article has a couple good examples. http://uxdesign.smashingmagazine.com/2011/05/27/getting-started-with-defensive-web-design/

Also twitter bootstrap has some nice styling that helps with that (scroll down to the Validation states section) http://twitter.github.com/bootstrap/base-css.html#forms

Highlighting each input box is a bit more complicated, so the easy way would be to just put an bootstrap alert at the top with details of what the user did wrong. http://twitter.github.com/bootstrap/components.html#alerts

string decode utf-8

the core functions are getBytes(String charset) and new String(byte[] data). you can use these functions to do UTF-8 decoding.

UTF-8 decoding actually is a string to string conversion, the intermediate buffer is a byte array. since the target is an UTF-8 string, so the only parameter for new String() is the byte array, which calling is equal to new String(bytes, "UTF-8")

Then the key is the parameter for input encoded string to get internal byte array, which you should know beforehand. If you don't, guess the most possible one, "ISO-8859-1" is a good guess for English user.

The decoding sentence should be

String decoded = new String(encoded.getBytes("ISO-8859-1"));

Remove tracking branches no longer on remote

This Below Commands Solved My problem.

// To Delete Branch Locally
git branch -d localBranchName


// To Delete Branch Remotely
git push origin --delete remoteBranchName

How to run Spyder in virtual environment?

What worked for me :

  1. run spyder from the environment (after source activate)
  2. go to Tools --> preferences --> python Interpreter and select the python file from the env you want to link to spyder ex : /home/you/anaconda3/envs/your_env/bin/python

Worked on ubuntu 16, spyder3, python3.6.

Display fullscreen mode on Tkinter

I think this is what you're looking for:

Tk.attributes("-fullscreen", True)  # substitute `Tk` for whatever your `Tk()` object is called

You can use wm_attributes instead of attributes, too.

Then just bind the escape key and add this to the handler:

Tk.attributes("-fullscreen", False)

An answer to another question alluded to this (with wm_attributes). So, that's how I found out. But, no one just directly went out and said it was the answer for some reason. So, I figured it was worth posting.

Here's a working example (tested on Xubuntu 14.04) that uses F11 to toggle fullscreen on and off and where escape will turn it off only:

import sys
if sys.version_info[0] == 2:  # Just checking your Python version to import Tkinter properly.
    from Tkinter import *
else:
    from tkinter import *


class Fullscreen_Window:

    def __init__(self):
        self.tk = Tk()
        self.tk.attributes('-zoomed', True)  # This just maximizes it so we can see the window. It's nothing to do with fullscreen.
        self.frame = Frame(self.tk)
        self.frame.pack()
        self.state = False
        self.tk.bind("<F11>", self.toggle_fullscreen)
        self.tk.bind("<Escape>", self.end_fullscreen)

    def toggle_fullscreen(self, event=None):
        self.state = not self.state  # Just toggling the boolean
        self.tk.attributes("-fullscreen", self.state)
        return "break"

    def end_fullscreen(self, event=None):
        self.state = False
        self.tk.attributes("-fullscreen", False)
        return "break"

if __name__ == '__main__':
    w = Fullscreen_Window()
    w.tk.mainloop()

If you want to hide a menu, too, there are only two ways I've found to do that. One is to destroy it. The other is to make a blank menu to switch between.

self.tk.config(menu=self.blank_menu)  # self.blank_menu is a Menu object

Then switch it back to your menu when you want it to show up again.

self.tk.config(menu=self.menu)  # self.menu is your menu.

What bitrate is used for each of the youtube video qualities (360p - 1080p), in regards to flowplayer?

Looking at this official google link: Youtube Live encoder settings, bitrates and resolutions they have this table:

                   240p       360p        480p        720p        1080p
Resolution      426 x 240   640 x 360   854x480     1280x720    1920x1080
Video Bitrates                   
Maximum         700 Kbps    1000 Kbps   2000 Kbps   4000 Kbps   6000 Kbps
Recommended     400 Kbps    750 Kbps    1000 Kbps   2500 Kbps   4500 Kbps
Minimum         300 Kbps    400 Kbps    500 Kbps    1500 Kbps   3000 Kbps

It would appear as though this is the case, although the numbers dont sync up to the google table above:

// the bitrates, video width and file names for this clip
      bitrates: [
        { url: "bbb-800.mp4", width: 480, bitrate: 800 }, //360p video
        { url: "bbb-1200.mp4", width: 720, bitrate: 1200 }, //480p video
        { url: "bbb-1600.mp4", width: 1080, bitrate: 1600 } //720p video
      ],

CSS selector based on element text?

It was probably discussed, but as of CSS3 there is nothing like what you need (see also "Is there a CSS selector for elements containing certain text?"). You will have to use additional markup, like this:

<li><span class="foo">some text</span></li>
<li>some other text</li>

Then refer to it the usual way:

li > span.foo {...}

send/post xml file using curl command line

With Jenkins 1.494, I was able to send a file to a job parameter on Ubuntu Linux 12.10 using curl with --form parameters:

curl --form name=myfileparam --form file=@/local/path/to/your/file.xml \
  -Fjson='{"parameter": {"name": "myfileparam", "file": "file"}}' \
  -Fsubmit=Build \
  http://user:password@jenkinsserver/job/jobname/build

On the Jenkins server, I configured a job that accepts a single parameter: a file upload parameter named myfileparam.

The first line of that curl call constructs a web form with a parameter named myfileparam (same as in the job); its value will be the contents of a file on the local file system named /local/path/to/your/file.txt. The @ symbol prefix tells curl to send a local file instead of the given filename.

The second line defines a JSON request that matches the form parameters on line one: a file parameter named myfileparam.

The third line activates the form's Build button. The forth line is the job URL with the "/build" suffix.

If this call is successful, curl returns 0. If it is unsuccessful, the error or exception from the service is printed to the console. This answer takes a lot from an old blog post relating to Hudson, which I deconstructed and re-worked for my own needs.

How to Position a table HTML?

You would want to use CSS to achieve that.

say you have a table with the attribute id="my_table"

You would want to write the following in your css file

#my_table{
    margin-top:10px //moves your table 10pixels down
    margin-left:10px //moves your table 10pixels right
}

if you do not have a CSS file then you may just add margin-top:10px, margin-left:10px to the style attribute in your table element like so

<table style="margin-top:10px; margin-left:10px;">
    ....
</table>

There are a lot of resources on the net describing CSS and HTML in detail

Could not commit JPA transaction: Transaction marked as rollbackOnly

My guess is that ServiceUser.method() is itself transactional. It shouldn't be. Here's the reason why.

Here's what happens when a call is made to your ServiceUser.method() method:

  1. the transactional interceptor intercepts the method call, and starts a transaction, because no transaction is already active
  2. the method is called
  3. the method calls MyService.doSth()
  4. the transactional interceptor intercepts the method call, sees that a transaction is already active, and doesn't do anything
  5. doSth() is executed and throws an exception
  6. the transactional interceptor intercepts the exception, marks the transaction as rollbackOnly, and propagates the exception
  7. ServiceUser.method() catches the exception and returns
  8. the transactional interceptor, since it has started the transaction, tries to commit it. But Hibernate refuses to do it because the transaction is marked as rollbackOnly, so Hibernate throws an exception. The transaction interceptor signals it to the caller by throwing an exception wrapping the hibernate exception.

Now if ServiceUser.method() is not transactional, here's what happens:

  1. the method is called
  2. the method calls MyService.doSth()
  3. the transactional interceptor intercepts the method call, sees that no transaction is already active, and thus starts a transaction
  4. doSth() is executed and throws an exception
  5. the transactional interceptor intercepts the exception. Since it has started the transaction, and since an exception has been thrown, it rollbacks the transaction, and propagates the exception
  6. ServiceUser.method() catches the exception and returns

HTML Drag And Drop On Mobile Devices

Jquery Touch Punch is great but what it also does is disable all the controls on the draggable div so to prevent this you have to alter the lines... (at the time of writing - line 75)

change

if (touchHandled || !self._mouseCapture(event.originalEvent.changedTouches[0])){

to read

if (touchHandled || !self._mouseCapture(event.originalEvent.changedTouches[0]) || event.originalEvent.target.localName === 'textarea'
        || event.originalEvent.target.localName === 'input' || event.originalEvent.target.localName === 'button' || event.originalEvent.target.localName === 'li'
        || event.originalEvent.target.localName === 'a'
        || event.originalEvent.target.localName === 'select' || event.originalEvent.target.localName === 'img') {

add as many ors as you want for each of the elements you want to 'unlock'

Hope that helps someone

How to convert a pymongo.cursor.Cursor into a dict?

Map function is fast way to convert big collection

from time import time


cursor = db.collection.find()

def f(x):
    return x['name']

t1 = time()
blackset = set(map(f, cursor))
print(time() - t1)

MySQL - How to select data by string length

Having a look at MySQL documentation for the string functions, we can also use CHAR_LENGTH() and CHARACTER_LENGTH() as well.

simple vba code gives me run time error 91 object variable or with block not set

Also you are trying to set value2 using Set keyword, which is not required. You can directly use rng.value2 = 1

below test code for ref.

Sub test()
    Dim rng As Range
    Set rng = Range("A1")
    rng.Value2 = 1
End Sub

memcpy() vs memmove()

Just because memcpy doesn't have to deal with overlapping regions, doesn't mean it doesn't deal with them correctly. The call with overlapping regions produces undefined behavior. Undefined behavior can work entirely as you expect on one platform; that doesn't mean it's correct or valid.

How to declare a structure in a header that is to be used by multiple files in c?

if this structure is to be used by some other file func.c how to do it?

When a type is used in a file (i.e. func.c file), it must be visible. The very worst way to do it is copy paste it in each source file needed it.

The right way is putting it in an header file, and include this header file whenever needed.

shall we open a new header file and declare the structure there and include that header in the func.c?

This is the solution I like more, because it makes the code highly modular. I would code your struct as:

#ifndef SOME_HEADER_GUARD_WITH_UNIQUE_NAME
#define SOME_HEADER_GUARD_WITH_UNIQUE_NAME

struct a
{ 
    int i;
    struct b
    {
        int j;
    }
};

#endif

I would put functions using this structure in the same header (the function that are "semantically" part of its "interface").

And usually, I could name the file after the structure name, and use that name again to choose the header guards defines.

If you need to declare a function using a pointer to the struct, you won't need the full struct definition. A simple forward declaration like:

struct a ;

Will be enough, and it decreases coupling.

or can we define the total structure in header file and include that in both source.c and func.c?

This is another way, easier somewhat, but less modular: Some code needing only your structure to work would still have to include all types.

In C++, this could lead to interesting complication, but this is out of topic (no C++ tag), so I won't elaborate.

then how to declare that structure as extern in both the files. ?

I fail to see the point, perhaps, but Greg Hewgill has a very good answer in his post How to declare a structure in a header that is to be used by multiple files in c?.

shall we typedef it then how?

  • If you are using C++, don't.
  • If you are using C, you should.

The reason being that C struct managing can be a pain: You have to declare the struct keyword everywhere it is used:

struct MyStruct ; /* Forward declaration */

struct MyStruct
{
   /* etc. */
} ;

void doSomething(struct MyStruct * p) /* parameter */
{
   struct MyStruct a ; /* variable */
   /* etc */
}

While a typedef will enable you to write it without the struct keyword.

struct MyStructTag ; /* Forward declaration */

typedef struct MyStructTag
{
   /* etc. */
} MyStruct ;

void doSomething(MyStruct * p) /* parameter */
{
   MyStruct a ; /* variable */
   /* etc */
}

It is important you still keep a name for the struct. Writing:

typedef struct
{
   /* etc. */
} MyStruct ;

will just create an anonymous struct with a typedef-ed name, and you won't be able to forward-declare it. So keep to the following format:

typedef struct MyStructTag
{
   /* etc. */
} MyStruct ;

Thus, you'll be able to use MyStruct everywhere you want to avoid adding the struct keyword, and still use MyStructTag when a typedef won't work (i.e. forward declaration)

Edit:

Corrected wrong assumption about C99 struct declaration, as rightfully remarked by Jonathan Leffler.

Edit 2018-06-01:

Craig Barnes reminds us in his comment that you don't need to keep separate names for the struct "tag" name and its "typedef" name, like I did above for the sake of clarity.

Indeed, the code above could well be written as:

typedef struct MyStruct
{
   /* etc. */
} MyStruct ;

IIRC, this is actually what C++ does with its simpler struct declaration, behind the scenes, to keep it compatible with C:

// C++ explicit declaration by the user
struct MyStruct
{
   /* etc. */
} ;
// C++ standard then implicitly adds the following line
typedef MyStruct MyStruct;

Back to C, I've seen both usages (separate names and same names), and none has drawbacks I know of, so using the same name makes reading simpler if you don't use C separate "namespaces" for structs and other symbols.

Testing web application on Mac/Safari when I don't own a Mac

The best site to test website and see them realtime on MAC Safari is by using

Browserstack

They have like 25 free minutes of first time testing and then 10 free mins each day..You can even test your pages from your local PC by using their WEB TUNNEL Feature

I tested 7 to 8 pages in browserstack...And I think they have some java debugging tool in the upper right corner that is great help

Search and get a line in Python

With regular expressions

import re
s="""
    qwertyuiop
    asdfghjkl

    zxcvbnm
    token qwerty

    asdfghjklñ
"""
>>> items=re.findall("token.*$",s,re.MULTILINE)
>>> for x in items:
...     print x
...
token qwerty

Loading another html page from javascript

Yes. In the javascript code:

window.location.href = "http://new.website.com/that/you/want_to_go_to.html";

How do I select the "last child" with a specific class name in CSS?

This is a cheeky answer, but if you are constrained to CSS only and able to reverse your items in the DOM, it might be worth considering. It relies on the fact that while there is no selector for the last element of a specific class, it is actually possible to style the first. The trick is to then use flexbox to display the elements in reverse order.

_x000D_
_x000D_
ul {_x000D_
  display: flex;_x000D_
  flex-direction: column-reverse;_x000D_
}_x000D_
_x000D_
/* Apply desired style to all matching elements. */_x000D_
ul > li.list {_x000D_
  background-color: #888;_x000D_
}_x000D_
_x000D_
/* Using a more specific selector, "unstyle" elements which are not the first. */_x000D_
ul > li.list ~ li.list {_x000D_
  background-color: inherit;_x000D_
}
_x000D_
<ul>_x000D_
  <li class="list">0</li>_x000D_
  <li>1</li>_x000D_
  <li class="list">2</li>_x000D_
</ul>_x000D_
<ul>_x000D_
  <li>0</li>_x000D_
  <li class="list">1</li>_x000D_
  <li class="list">2</li>_x000D_
  <li>3</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

Adding items to end of linked list

public static Node insertNodeAtTail(Node head,Object data) {
               Node node = new Node(data);
                 node.next = null;
                if (head == null){
                    return node;
                }
                else{
                    Node temp = head;
                    while(temp.next != null){
                        temp = temp.next;
                    }
                    temp.next = node; 
                    return head;
                }        
    }

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

I had a similar issue to this. I solved it by making all the projects within my solution target the same .NET Framework 4 Client Profile and then rebuilding the entire solution.

Selectors in Objective-C?

From my understanding of the Apple documentation, a selector represents the name of the method that you want to call. The nice thing about selectors is you can use them in cases where the exact method to be called varies. As a simple example, you can do something like:

SEL selec;
if (a == b) {
selec = @selector(method1)
}
else
{
selec = @selector(method2)
};
[self performSelector:selec];

jQuery select change event get selected option

$('select').on('change', function (e) {
    var optionSelected = $("option:selected", this);
    var valueSelected = this.value;
    ....
});

Remove ListView items in Android

I think if u add the following code, it will work

listview.invalidateViews();

To remove an item, Just remove that item from the arraylist that we passed to the adapter and do listview.invalidateViews();
This will refresh the listview

pandas python how to count the number of records or rows in a dataframe

Simply, row_num = df.shape[0] # gives number of rows, here's the example:

import pandas as pd
import numpy as np

In [322]: df = pd.DataFrame(np.random.randn(5,2), columns=["col_1", "col_2"])

In [323]: df
Out[323]: 
      col_1     col_2
0 -0.894268  1.309041
1 -0.120667 -0.241292
2  0.076168 -1.071099
3  1.387217  0.622877
4 -0.488452  0.317882

In [324]: df.shape
Out[324]: (5, 2)

In [325]: df.shape[0]   ## Gives no. of rows/records
Out[325]: 5

In [326]: df.shape[1]   ## Gives no. of columns
Out[326]: 2

How do I append a node to an existing XML file in java

The following complete example will read an existing server.xml file from the current directory, append a new Server and re-write the file to server.xml. It does not work without an existing .xml file, so you will need to modify the code to handle that case.

import java.util.*;
import javax.xml.transform.*;
import javax.xml.transform.stream.*;
import javax.xml.transform.dom.*;
import org.w3c.dom.*;
import javax.xml.parsers.*;

public class AddXmlNode {
    public static void main(String[] args) throws Exception {

        DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
        DocumentBuilder documentBuilder = documentBuilderFactory.newDocumentBuilder();
        Document document = documentBuilder.parse("server.xml");
        Element root = document.getDocumentElement();

        Collection<Server> servers = new ArrayList<Server>();
        servers.add(new Server());

        for (Server server : servers) {
            // server elements
            Element newServer = document.createElement("server");

            Element name = document.createElement("name");
            name.appendChild(document.createTextNode(server.getName()));
            newServer.appendChild(name);

            Element port = document.createElement("port");
            port.appendChild(document.createTextNode(Integer.toString(server.getPort())));
            newServer.appendChild(port);

            root.appendChild(newServer);
        }

        DOMSource source = new DOMSource(document);

        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        Transformer transformer = transformerFactory.newTransformer();
        StreamResult result = new StreamResult("server.xml");
        transformer.transform(source, result);
    }

    public static class Server {
        public String getName() { return "foo"; }
        public Integer getPort() { return 12345; }
    }
}

Example server.xml file:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Servers>
  <server>
    <name>something</name>
    <port>port</port>
  </server>
</Servers>

The main change to your code is not creating a new "root" element. The above example just uses the current root node from the existing server.xml and then just appends a new Server element and re-writes the file.

Shuffle DataFrame rows

Here is another way:

df['rnd'] = np.random.rand(len(df)) df = df.sort_values(by='rnd', inplace=True).drop('rnd', axis=1)

Convert an integer to a float number

intutils.ToFloat32

// ToFloat32 converts a int num to a float32 num
func ToFloat32(in int) float32 {
    return float32(in)
}

// ToFloat64 converts a int num to a float64 num
func ToFloat64(in int) float64 {
    return float64(in)
}

Batch: Remove file extension

You can use %%~nf to get the filename only as described in the reference for for:

@echo off
    for /R "C:\Users\Admin\Ordner" %%f in (*.flv) do (
    echo %%~nf
)
pause

The following options are available:

Variable with modifier  Description

%~I                     Expands %I which removes any surrounding 
                        quotation marks ("").
%~fI                    Expands %I to a fully qualified path name.
%~dI                    Expands %I to a drive letter only.
%~pI                    Expands %I to a path only.
%~nI                    Expands %I to a file name only.
%~xI                    Expands %I to a file extension only.
%~sI                    Expands path to contain short names only.
%~aI                    Expands %I to the file attributes of file.
%~tI                    Expands %I to the date and time of file.
%~zI                    Expands %I to the size of file.
%~$PATH:I               Searches the directories listed in the PATH environment 
                        variable and expands %I to the fully qualified name of 
                        the first one found. If the environment variable name is 
                        not defined or the file is not found by the search,
                        this modifier expands to the empty string.    

How do I set up DNS for an apex domain (no www) pointing to a Heroku app?

You are not allowed to have a CNAME record for the domain, as the CNAME is an aliasing feature that covers all data types (regardless of whether the client looks for MX, NS or SOA records). CNAMEs also always refer to a new name, not an ip-address, so there are actually two errors in the single line

@                        IN CNAME   88.198.38.XXX

Changing that CNAME to an A record should make it work, provided the ip-address you use is the correct one for your Heroku app.

The only correct way in DNS to make a simple domain.com name work in the browser, is to point the domain to an IP-adress with an A record.

Can I hide/show asp:Menu items based on role?

You can remove unwanted menu items in Page_Load, like this:

    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Roles.IsUserInRole("Admin"))
        {
            MenuItemCollection menuItems = mTopMenu.Items;
            MenuItem adminItem = new MenuItem();
            foreach (MenuItem menuItem in menuItems)
            {
                if (menuItem.Text == "Roles")
                    adminItem = menuItem;
            }
            menuItems.Remove(adminItem);
        }
    }

I'm sure there's a neater way to find the right item to remove, but this one works. You could also add all the wanted menu items in a Page_Load method, instead of adding them in the markup.

Are querystring parameters secure in HTTPS (HTTP + SSL)?

remember, SSL/TLS operates at the Transport Layer, so all the crypto goo happens under the application-layer HTTP stuff.

http://en.wikipedia.org/wiki/File:IP_stack_connections.svg

that's the long way of saying, "Yes!"

error 1265. Data truncated for column when trying to load data from txt file

This error can also be the result of not having the line,

FIELDS SPECIFIED BY ','

(if you're using commas to separate the fields) in your MySQL syntax, as described in this page of the MySQL docs.

How to move table from one tablespace to another in oracle 11g

Moving tables:

First run:

SELECT 'ALTER TABLE <schema_name>.' || OBJECT_NAME ||' MOVE TABLESPACE '||' <tablespace_name>; '
FROM ALL_OBJECTS
WHERE OWNER = '<schema_name>'
AND OBJECT_TYPE = 'TABLE' <> '<TABLESPACE_NAME>';

-- Or suggested in the comments (did not test it myself)

SELECT 'ALTER TABLE <SCHEMA>.' || TABLE_NAME ||' MOVE TABLESPACE '||' TABLESPACE_NAME>; ' 
FROM dba_tables 
WHERE OWNER = '<SCHEMA>' 
AND TABLESPACE_NAME <> '<TABLESPACE_NAME>

Where <schema_name> is the name of the user. And <tablespace_name> is the destination tablespace.

As a result you get lines like:

ALTER TABLE SCOT.PARTS MOVE TABLESPACE USERS;

Paste the results in a script or in a oracle sql developer like application and run it.

Moving indexes:

First run:

SELECT 'ALTER INDEX <schema_name>.'||INDEX_NAME||' REBUILD TABLESPACE <tablespace_name>;' 
FROM ALL_INDEXES
WHERE OWNER = '<schema_name>'
AND TABLESPACE_NAME NOT LIKE '<tablespace_name>';

The last line in this code could save you a lot of time because it filters out the indexes which are already in the correct tablespace.

As a result you should get something like:

ALTER INDEX SCOT.PARTS_NO_PK REBUILD TABLESPACE USERS;

Paste the results in a script or in a oracle sql developer like application and run it.

Last but not least, moving LOBs:

First run:

SELECT 'ALTER TABLE <schema_name>.'||LOWER(TABLE_NAME)||' MOVE LOB('||LOWER(COLUMN_NAME)||') STORE AS (TABLESPACE <table_space>);'
FROM DBA_TAB_COLS
WHERE OWNER = '<schema_name>' AND DATA_TYPE like '%LOB%';

This moves the LOB objects to the other tablespace.

As a result you should get something like:

ALTER TABLE SCOT.bin$6t926o3phqjgqkjabaetqg==$0 MOVE LOB(calendar) STORE AS (TABLESPACE USERS);

Paste the results in a script or in a oracle sql developer like application and run it.

O and there is one more thing:

For some reason I wasn't able to move 'DOMAIN' type indexes. As a work around I dropped the index. changed the default tablespace of the user into de desired tablespace. and then recreate the index again. There is propably a better way but it worked for me.

JUnit: how to avoid "no runnable methods" in test utils classes

What about adding an empty test method to these classes?

public void avoidAnnoyingErrorMessageWhenRunningTestsInAnt() {
    assertTrue(true); // do nothing;
}

HTTP test server accepting GET/POST requests

http://requestb.in was similar to the already mentioned tools and also had a very nice UI.

RequestBin gives you a URL that will collect requests made to it and let you inspect them in a human-friendly way. Use RequestBin to see what your HTTP client is sending or to inspect and debug webhook requests.

Though it has been discontinued as of Mar 21, 2018.

We have discontinued the publicly hosted version of RequestBin due to ongoing abuse that made it very difficult to keep the site up reliably. Please see instructions for setting up your own self-hosted instance.

Change x axes scale in matplotlib

This is not so much an answer to your original question as to one of the queries you had in the body of your question.

A little preamble, so that my naming doesn't seem strange:

import matplotlib
from matplotlib import rc
from matplotlib.figure import Figure
ax = self.figure.add_subplot( 111 )

As has been mentioned you can use ticklabel_format to specify that matplotlib should use scientific notation for large or small values:

ax.ticklabel_format(style='sci',scilimits=(-3,4),axis='both')

You can affect the way that this is displayed using the flags in rcParams (from matplotlib import rcParams) or by setting them directly. I haven't found a more elegant way of changing between '1e' and 'x10^' scientific notation than:

ax.xaxis.major.formatter._useMathText = True

This should give you the more Matlab-esc, and indeed arguably better appearance. I think the following should do the same:

rc('text', usetex=True)

Changing the highlight color when selecting text in an HTML text input

I realise this is an old question but for anyone who does come across it this can be done using contenteditable as shown in this JSFiddle.

Kudos to Alex who mentioned this in the comments (I didn't see that until now!)

How can I combine two commits into one commit?

You want to git rebase -i to perform an interactive rebase.

If you're currently on your "commit 1", and the commit you want to merge, "commit 2", is the previous commit, you can run git rebase -i HEAD~2, which will spawn an editor listing all the commits the rebase will traverse. You should see two lines starting with "pick". To proceed with squashing, change the first word of the second line from "pick" to "squash". Then save your file, and quit. Git will squash your first commit into your second last commit.

Note that this process rewrites the history of your branch. If you are pushing your code somewhere, you'll have to git push -f and anybody sharing your code will have to jump through some hoops to pull your changes.

Note that if the two commits in question aren't the last two commits on the branch, the process will be slightly different.

Apply formula to the entire column

This is for those who want to overwrite the column cells quickly (without cutting and copying). This is the same as double-clicking the cell box but unlike double-clicking, it still works after the first try.

  1. Select the column cell you would like to copy downwards
  2. Press Ctrl+Shift+ to select the cells below
  3. Press Ctrl+Enter to copy the contents of the first cell into the cells below

BONUS:

The shortcut for going to the bottom-most content (to double-check the copy) is Ctrl+. To go back up you can use Ctrl+ but if your top rows are frozen you'll also have to press Enter a few times.

PHP/MySQL: How to create a comment section in your website

You can create a 'comment' table, with an id as primary key, then you add a text field to capture the text inserted by the user and you need another field to link the comment table to the article table (foreign key). Plus you need a field to store the user that has entered a comment, this field can be the user's email. Then you capture via GET or POST the user's email and comment and you insert everything in the DB:

"INSERT INTO comment (comment, email, approved) VALUES ('$comment', '$email', '$approved')"

This is a first hint. Of course adding a comment feature it takes a little bit. Then you should think about a form to let the admin to approve the comments and how to publish the comments in the end of articles.

Check whether a string is not null and not empty

Use org.apache.commons.lang.StringUtils

I like to use Apache commons-lang for these kinds of things, and especially the StringUtils utility class:

import org.apache.commons.lang.StringUtils;

if (StringUtils.isNotBlank(str)) {
    ...
} 

if (StringUtils.isBlank(str)) {
    ...
} 

How to return PDF to browser in MVC?

You must specify :

Response.AppendHeader("content-disposition", "inline; filename=file.pdf");
return new FileStreamResult(stream, "application/pdf")

For the file to be opened directly in the browser instead of being downloaded

Is there a way to make text unselectable on an HTML page?

If it looks bad you can use CSS to change the appearance of selected sections.

How to select option in drop down using Capybara

If you take a look at the source of the select method, you can see that what it does when you pass a from key is essentially:

find(:select, from, options).find(:option, value, options).select_option

In other words, it finds the <select> you're interested in, then finds the <option> within that, then calls select_option on the <option> node.

You've already pretty much done the first two things, I'd just rearrange them. Then you can tack the select_option method on the end:

find('#organizationSelect').find(:xpath, 'option[2]').select_option

What is the best IDE for C Development / Why use Emacs over an IDE?

Emacs is an IDE.

edit: OK, I'll elaborate. What is an IDE?

As a starting point, let's expand the acronym: Integrated Development Environment. To analyze this, I start from the end.

An environment is, generally speaking, the part of the world that surrounds the point of view. In this case, it is what we see on our monitor (perhaps hear from our speakers) and manipulate through our keyboard (and perhaps a mouse).

Development is what we want to do in this environment, its purpose, if you want. We use the environment to develop software. This defines what subparts we need: an editor, an interface to the REPL, resp. the compiler, an interface to the debugger, and access to online documentation (this list may not be exhaustive).

Integrated means that all parts of the environment are somehow under a uniform surface. In an IDE, we can access and use the different subparts with a minimum of switching; we don't have to leave our defined environment. This integration lets the different subparts interact better. For example, the editor can know about what language we write in, and give us symbol autocompletion, jump-to-definition, auto-indentation, syntax highlighting, etc.. It can get information from the compiler, automatically jump to errors, and highlight them. In most, if not all IDEs, the editor is naturally at the heart of the development process.

Emacs does all this, it does it with a wide range of languages and tasks, and it does it with excellence, since it is seamlessly expandable by the user wherever he misses anything.

Counterexample: you could develop using something like Notepad, access documentation through Firefox and XPdf, and steer the compiler and debugger from a shell. This would be a Development Environment, but it would not be integrated.

Creating a byte array from a stream

While Jon's answer is correct, he is rewriting code that already exists in CopyTo. So for .Net 4 use Sandip's solution, but for previous version of .Net use Jon's answer. Sandip's code would be improved by use of "using" as exceptions in CopyTo are, in many situations, quite likely and would leave the MemoryStream not disposed.

public static byte[] ReadFully(Stream input)
{
    using (MemoryStream ms = new MemoryStream())
    {
        input.CopyTo(ms);
        return ms.ToArray();
    }
}

Remove last characters from a string in C#. An elegant way?

You can use TrimEnd. It's efficient as well and looks clean.

"Name,".TrimEnd(',');

Overriding a JavaScript function while referencing the original

The Proxy pattern might help you:

(function() {
    // log all calls to setArray
    var proxied = jQuery.fn.setArray;
    jQuery.fn.setArray = function() {
        console.log( this, arguments );
        return proxied.apply( this, arguments );
    };
})();

The above wraps its code in a function to hide the "proxied"-variable. It saves jQuery's setArray-method in a closure and overwrites it. The proxy then logs all calls to the method and delegates the call to the original. Using apply(this, arguments) guarantees that the caller won't be able to notice the difference between the original and the proxied method.

Fastest way to duplicate an array in JavaScript - slice vs. 'for' loop

Technically slice is the fastest way. However, it is even faster if you add the 0 begin index.

myArray.slice(0);

is faster than

myArray.slice();

http://jsperf.com/cloning-arrays/3

How to create a table from select query result in SQL Server 2008

use SELECT...INTO

The SELECT INTO statement creates a new table and populates it with the result set of the SELECT statement. SELECT INTO can be used to combine data from several tables or views into one table. It can also be used to create a new table that contains data selected from a linked server.

Example,

SELECT col1, col2 INTO #a -- <<== creates temporary table
FROM   tablename

Standard Syntax,

SELECT  col1, ....., col@      -- <<== select as many columns as you want
        INTO [New tableName]
FROM    [Source Table Name]

How to Increase Import Size Limit in phpMyAdmin

Be sure you are editing php.ini not php-development.ini or php-production.ini, php.ini file type is Configuration setting and when you edit it in editor it show .ini extension. You can find php.ini here: xampp/php/php

Then

upload_max_filesize = 128M
post_max_size = 128M
max_execution_time = 900
max_input_time = 50000000
memory_limit = 256M

enter image description here]

Java: How to stop thread?

One possible way is to do something like this:

public class MyThread extends Thread {
    @Override
    public void run() {
        while (!this.isInterrupted()) {
            //
        }
    }
}

And when you want to stop your thread, just call a method interrupt():

myThread.interrupt();

Of course, this won't stop thread immediately, but in the following iteration of the loop above. In the case of downloading, you need to write a non-blocking code. It means, that you will attempt to read new data from the socket only for a limited amount of time. If there are no data available, it will just continue. It may be done using this method from the class Socket:

mySocket.setSoTimeout(50);

In this case, timeout is set up to 50 ms. After this time has gone and no data was read, it throws an SocketTimeoutException. This way, you may write iterative and non-blocking thread, which may be killed using the construction above.

It's not possible to kill thread in any other way and you've to implement such a behavior yourself. In past, Thread had some method (not sure if kill() or stop()) for this, but it's deprecated now. My experience is, that some implementations of JVM doesn't even contain that method currently.

How do I use select with date condition?

If you put in

SELECT * FROM Users WHERE RegistrationDate >= '1/20/2009' 

it will automatically convert the string '1/20/2009' into the DateTime format for a date of 1/20/2009 00:00:00. So by using >= you should get every user whose registration date is 1/20/2009 or more recent.

Edit: I put this in the comment section but I should probably link it here as well. This is an article detailing some more in depth ways of working with DateTime's in you queries: http://www.databasejournal.com/features/mssql/article.php/2209321/Working-with-SQL-Server-DateTime-Variables-Part-Three---Searching-for-Particular-Date-Values-and-Ranges.htm

Export DataTable to Excel with Open Xml SDK in c#

You could try taking a look at this libary. I've used it for one of my projects and found it very easy to work with, reliable and fast (I only used it for exporting data).

http://epplus.codeplex.com/

How do I manually create a file with a . (dot) prefix in Windows? For example, .htaccess

You can do this in any program other than Explorer, e.g. Notepad, cmd.exe etc.

You just can't do it in Explorer, and Raymond Chen has offered an explanation as to why not.

Convert array to string in NodeJS

toString is a function, not a property. You'll want this:

console.log(aa.toString());

Alternatively, use join to specify the separator (toString() === join(','))

console.log(aa.join(' and '));

C# Syntax - Split String into Array by Comma, Convert To Generic List, and Reverse Order

I realize that this question is quite old, but I had a similar problem, except my string had spaces included in it. For those that need to know how to separate a string with more than just commas:

string str = "Tom, Scott, Bob";
  IList<string> names = str.Split(new string[] {","," "},
  StringSplitOptions.RemoveEmptyEntries);

The StringSplitOptions removes the records that would only be a space char...

How to reformat JSON in Notepad++?

It's not an NPP solution, but in a pinch, you can use this online JSON Formatter and then just paste the formatted text into NPP and then select Javascript as the language.

How to make g++ search for header files in a specific directory?

gcc -I/path -L/path
  • -I /path path to include, gcc will find .h files in this path

  • -L /path contains library files, .a, .so

How to go to each directory and execute a command?

If the toplevel folder is known you can just write something like this:

for dir in `ls $YOUR_TOP_LEVEL_FOLDER`;
do
    for subdir in `ls $YOUR_TOP_LEVEL_FOLDER/$dir`;
    do
      $(PLAY AS MUCH AS YOU WANT);
    done
done

On the $(PLAY AS MUCH AS YOU WANT); you can put as much code as you want.

Note that I didn't "cd" on any directory.

Cheers,

Viewing all `git diffs` with vimdiff

You can try git difftool, it is designed to do this stuff.

First, you need to config diff tool to vimdiff

git config diff.tool vimdiff

Then, when you want to diff, just use git difftool instead of git diff. It will work as you expect.

How to sort an array of objects in Java?

You can implement the "Comparable" interface on a class whose objects you want to compare.

And also implement the "compareTo" method in that.

Add the instances of the class in an ArrayList

Then the "java.utils.Collections.sort()" method will do the necessary magic.

Here's--->(https://deva-codes.herokuapp.com/CompareOnTwoKeys) a working example where objects are sorted based on two keys first by the id and then by name.

Laravel Migration Error: Syntax error or access violation: 1071 Specified key was too long; max key length is 767 bytes

For someone who don't want to change AppServiceProvider.php. (In my opinion, it's bad idea to change AppServiceProvider.php just for migration)

You can add back the data length to the migration file under database/migrations/ as below:

create_users_table.php

$table->string('name',64);
$table->string('email',128)->unique();

create_password_resets_table.php

$table->string('email',128)->index();

How to call Android contacts list?

        Cursor phones = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,null,null, null);
        while (phones.moveToNext())
        {
        String Name=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME)
        String Number=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));

        }

How to execute a java .class from the command line

My situation was a little complicated. I had to do three steps since I was using a .dll in the resources directory, for JNI code. My files were

S:\Accessibility\tools\src\main\resources\dlls\HelloWorld.dll
S:\Accessibility\tools\src\test\java\com\accessibility\HelloWorld.class

My code contained the following line

System.load(HelloWorld.class.getResource("/dlls/HelloWorld.dll").getPath());

First, I had to move to the classpath directory

cd /D "S:\Accessibility\tools\src\test\java"

Next, I had to change the classpath to point to the current directory so that my class would be loaded and I had to change the classpath to point to he resources directory so my dll would be loaded.

set classpath=%classpath%;.;..\..\..\src\main\resources; 

Then, I had to run java using the classname.

java com.accessibility.HelloWorld 

'this' is undefined in JavaScript class methods

JavaScript's OOP is a little funky (or a lot) and it takes some getting used to. This first thing you need to keep in mind is that there are no Classes and thinking in terms of classes can trip you up. And in order to use a method attached to a Constructor (the JavaScript equivalent of a Class definition) you need to instantiate your object. For example:

Ninja = function (name) {
    this.name = name;
};
aNinja = new Ninja('foxy');
aNinja.name; //-> 'foxy'

enemyNinja = new Ninja('boggis');
enemyNinja.name; //=> 'boggis'

Note that Ninja instances have the same properties but aNinja cannot access the properties of enemyNinja. (This part should be really easy/straightforward) Things get a bit different when you start adding stuff to the prototype:

Ninja.prototype.jump = function () {
   return this.name + ' jumped!';
};
Ninja.prototype.jump(); //-> Error.
aNinja.jump(); //-> 'foxy jumped!'
enemyNinja.jump(); //-> 'boggis jumped!'

Calling this directly will throw an error because this only points to the correct object (your "Class") when the Constructor is instantiated (otherwise it points to the global object, window in a browser)

IIS7 Cache-Control

I use this

<staticContent>
<clientCache cacheControlCustom="public" cacheControlMode="UseMaxAge" cacheControlMaxAge="500.00:00:00" />
</staticContent>

to cache static content for 500 days with public cache-control header.

VarBinary vs Image SQL Server Data Type to Store Binary Data?

varbinary(max) is the way to go (introduced in SQL Server 2005)

How to get 0-padded binary representation of an integer in java?

You can use lib https://github.com/kssource/BitSequence. It accept a number and return bynary string, padded and/or grouped.

String s = new BitSequence(2, 16).toBynaryString(ALIGN.RIGHT, GROUP.CONTINOUSLY));  
return  
0000000000000010  

another examples:

[10, -20, 30]->00001010 11101100 00011110
i=-10->00000000000000000000000000001010
bi=10->1010
sh=10->00 0000 0000 1010
l=10->00000001 010
by=-10->1010
i=-10->bc->11111111 11111111 11111111 11110110

How do I style radio buttons with images - laughing smiley for good, sad smiley for bad?

You can take advantage of CSS3 to do that, by hidding the by-default input radio button with CSS3 rules:

.class-selector input{
    margin:0;padding:0;
    -webkit-appearance:none;
       -moz-appearance:none;
            appearance:none;
}

And then using labels for images as the following demos:

JSFiddle Demo 1

From top to bottom: Unfocused, MasterCard Selected, Visa Selected, Mastercard hovered

JSFiddle Demo 2

Visa selected

Gist - How to use images for radio-buttons

How to normalize a signal to zero mean and unit variance?

You can determine the mean of the signal, and just subtract that value from all the entries. That will give you a zero mean result.

To get unit variance, determine the standard deviation of the signal, and divide all entries by that value.

Capturing mobile phone traffic on Wireshark

Here are some suggestions:

  1. For Android phones, any network: Root your phone, then install tcpdump on it. This app is a tcpdump wrapper that will install tcpdump and enable you to start captures using a GUI. Tip: You will need to make sure you supply the right interface name for the capture and this varies from one device to another, eg -i eth0 or -i tiwlan0 - or use -i any to log all interfaces

  2. For Android 4.0+ phones: Android PCAP from Kismet uses the USB OTG interface to support packet capture without requiring root. I haven't tried this app, and there are some restrictions on the type of devices supported (see their page)

  3. For Android phones: tPacketCapture uses the Android VPN service to intercept packets and capture them. I have used this app successfully, but it also seems to affect the performance with large traffic volumes (eg video streaming)

  4. For IOS 5+ devices, any network: iOS 5 added a remote virtual interface (RVI) facility that lets you use Mac OS X packet trace programs to capture traces from an iOS device. See here for more details

  5. For all phones, wi-fi only: Set up your PC as a wireless access point, then run wireshark on the PC

  6. For all phones, wi-fi only: Get a capture device that can sniff wi-fi. This has the advantage of giving you 802.11x headers as well, but you may miss some of the packets

  7. Capture using a VPN server: Its fairly easy to set-up your own VPN server using OpenVPN. You can then route your traffic through your server by setting up the mobile device as a VPN client and capture the traffic on the server end.

How to convert Observable<any> to array[]

Using HttpClient (Http's replacement) in Angular 4.3+, the entire mapping/casting process is made simpler/eliminated.

Using your CountryData class, you would define a service method like this:

getCountries()  {
  return this.httpClient.get<CountryData[]>('http://theUrl.com/all');
}

Then when you need it, define an array like this:

countries:CountryData[] = [];

and subscribe to it like this:

this.countryService.getCountries().subscribe(countries => this.countries = countries);

A complete setup answer is posted here also.

Understanding SQL Server LOCKS on SELECT queries

A SELECT in SQL Server will place a shared lock on a table row - and a second SELECT would also require a shared lock, and those are compatible with one another.

So no - one SELECT cannot block another SELECT.

What the WITH (NOLOCK) query hint is used for is to be able to read data that's in the process of being inserted (by another connection) and that hasn't been committed yet.

Without that query hint, a SELECT might be blocked reading a table by an ongoing INSERT (or UPDATE) statement that places an exclusive lock on rows (or possibly a whole table), until that operation's transaction has been committed (or rolled back).

Problem of the WITH (NOLOCK) hint is: you might be reading data rows that aren't going to be inserted at all, in the end (if the INSERT transaction is rolled back) - so your e.g. report might show data that's never really been committed to the database.

There's another query hint that might be useful - WITH (READPAST). This instructs the SELECT command to just skip any rows that it attempts to read and that are locked exclusively. The SELECT will not block, and it will not read any "dirty" un-committed data - but it might skip some rows, e.g. not show all your rows in the table.

MSBUILD : error MSB1008: Only one project can be specified

It turns out the trailing slash in the PublishDir property is escaping the end quote. Escaping the trailing slash solved my problem.

/p:PublishDir="\\BSIIS3\c$\DATA\WEBSITES\benesys.net\benesys.net\TotalEducationTest\\"

This way we can use quotes for paths that have whitespace in properties that MSBuild requires the trailing slash.

I know this is an old post, but I feel like I needed to share this with someone :-)

How to clear variables in ipython?

%reset seems to clear defined variables.

How can I simulate an anchor click via jquery?

I believe you can use:

$('#yourLink').bind('click', function() {
  //Do something over here
});

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

This will easily trigger the click function, without actually clicking on it.

Run Bash Command from PHP

Check if have not set a open_basedir in php.ini or .htaccess of domain what you use. That will jail you in directory of your domain and php will get only access to execute inside this directory.

How to convert NSData to byte array in iPhone?

Already answered, but to generalize to help other readers:

    //Here:   NSData * fileData;
    uint8_t * bytePtr = (uint8_t  * )[fileData bytes];

    // Here, For getting individual bytes from fileData, uint8_t is used.
    // You may choose any other data type per your need, eg. uint16, int32, char, uchar, ... .
    // Make sure, fileData has atleast number of bytes that a single byte chunk would need. eg. for int32, fileData length must be > 4 bytes. Makes sense ?

    // Now, if you want to access whole data (fileData) as an array of uint8_t
    NSInteger totalData = [fileData length] / sizeof(uint8_t);

    for (int i = 0 ; i < totalData; i ++)
    {
        NSLog(@"data byte chunk : %x", bytePtr[i]);
    }

How to insert a value that contains an apostrophe (single quote)?

The apostrophe character can be inserted by calling the CHAR function with the apostrophe's ASCII table lookup value, 39. The string values can then be concatenated together with a concatenate operator.

Insert into Person
  (First, Last)
Values
  'Joe',
  concat('O',char(39),'Brien')

How can I set the aspect ratio in matplotlib?

A simple option using plt.gca() to get current axes and set aspect

        plt.gca().set_aspect('equal')

in place of your last line

Is it possible to view RabbitMQ message contents directly from the command line?

I wrote rabbitmq-dump-queue which allows dumping messages from a RabbitMQ queue to local files and requeuing the messages in their original order.

Example usage (to dump the first 50 messages of queue incoming_1):

rabbitmq-dump-queue -url="amqp://user:[email protected]:5672/" -queue=incoming_1 -max-messages=50 -output-dir=/tmp

how to use getSharedPreferences in android

//Set Preference
SharedPreferences myPrefs = getSharedPreferences("myPrefs", MODE_WORLD_READABLE);
SharedPreferences.Editor prefsEditor;  
prefsEditor = myPrefs.edit();  
//strVersionName->Any value to be stored  
prefsEditor.putString("STOREDVALUE", strVersionName);  
prefsEditor.commit();

//Get Preferenece  
SharedPreferences myPrefs;    
myPrefs = getSharedPreferences("myPrefs", MODE_WORLD_READABLE);  
String StoredValue=myPrefs.getString("STOREDVALUE", "");

Try this..

Passing a method parameter using Task.Factory.StartNew

For passing a single integer I agree with Reed Copsey's answer. If in the future you are going to pass more complicated constucts I personally like to pass all my variables as an Anonymous Type. It will look something like this:

foreach(int id in myIdsToCheck)
{
    Task.Factory.StartNew( (Object obj) => 
        {
           var data = (dynamic)obj;
           CheckFiles(data.id, theBlockingCollection,
               cancelCheckFile.Token, 
               TaskCreationOptions.LongRunning, 
               TaskScheduler.Default);
        }, new { id = id }); // Parameter value
}

You can learn more about it in my blog

difference between @size(max = value ) and @min(value) @max(value)

package com.mycompany;

import javax.validation.constraints.Min;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;

public class Car {

    @NotNull
    private String manufacturer;

    @NotNull
    @Size(min = 2, max = 14)
    private String licensePlate;

    @Min(2)
    private int seatCount;

    public Car(String manufacturer, String licencePlate, int seatCount) {
        this.manufacturer = manufacturer;
        this.licensePlate = licencePlate;
        this.seatCount = seatCount;
    }

    //getters and setters ...
}

@NotNull, @Size and @Min are so-called constraint annotations, that we use to declare constraints, which shall be applied to the fields of a Car instance:

manufacturer shall never be null

licensePlate shall never be null and must be between 2 and 14 characters long

seatCount shall be at least 2.

How do I correctly clone a JavaScript object?

Using defaults (historically specific to nodejs but now usable from the browser thanks to modern JS):

import defaults from 'object.defaults';

const myCopy = defaults({}, myObject);

git clone from another directory

In case you have space in your path, wrap it in double quotes:

$ git clone "//serverName/New Folder/Target" f1/

instantiate a class from a variable in PHP?

If You Use Namespaces

In my own findings, I think it's good to mention that you (as far as I can tell) must declare the full namespace path of a class.

MyClass.php

namespace com\company\lib;
class MyClass {
}

index.php

namespace com\company\lib;

//Works fine
$i = new MyClass();

$cname = 'MyClass';

//Errors
//$i = new $cname;

//Works fine
$cname = "com\\company\\lib\\".$cname;
$i = new $cname;

Windows: XAMPP vs WampServer vs EasyPHP vs alternative

I'm using EasyPHP in making my Thesis about Content Management System. So far, this tool is very good and easy to use.

console.writeline and System.out.println

Here are the primary differences between using System.out/.err/.in and System.console():

  • System.console() returns null if your application is not run in a terminal (though you can handle this in your application)
  • System.console() provides methods for reading password without echoing characters
  • System.out and System.err use the default platform encoding, while the Console class output methods use the console encoding

This latter behaviour may not be immediately obvious, but code like this can demonstrate the difference:

public class ConsoleDemo {
  public static void main(String[] args) {
    String[] data = { "\u250C\u2500\u2500\u2500\u2500\u2500\u2510", 
        "\u2502Hello\u2502",
        "\u2514\u2500\u2500\u2500\u2500\u2500\u2518" };
    for (String s : data) {
      System.out.println(s);
    }
    for (String s : data) {
      System.console().writer().println(s);
    }
  }
}

On my Windows XP which has a system encoding of windows-1252 and a default console encoding of IBM850, this code will write:

???????
?Hello?
???????
+-----+
¦Hello¦
+-----+

Note that this behaviour depends on the console encoding being set to a different encoding to the system encoding. This is the default behaviour on Windows for a bunch of historical reasons.

Getting only Month and Year from SQL DATE

SELECT DATEPART(yy, DateVal)
SELECT DATEPART(MM, DateVal)
SELECT DATENAME(MM, DateVal)

Display MessageBox in ASP

Here is one way of doing it:

    <%
       Dim message    
       message = "This is my message"
       Response.Write("<script language=VBScript>MsgBox """ + message + """</script>") 
    %>

How do I pretty-print existing JSON data with Java?

I fount a very simple solution:

<dependency>
    <groupId>com.cedarsoftware</groupId>
    <artifactId>json-io</artifactId>
    <version>4.5.0</version>
</dependency>

Java code:

import com.cedarsoftware.util.io.JsonWriter;
//...
String jsonString = "json_string_plain_text";
System.out.println(JsonWriter.formatJson(jsonString));

What is the use of static synchronized method in java?

Suppose there are multiple static synchronized methods (m1, m2, m3, m4) in a class, and suppose one thread is accessing m1, then no other thread at the same time can access any other static synchronized methods.

How to convert all tables from MyISAM into InnoDB?

Run this SQL statement (in the MySQL client, phpMyAdmin, or wherever) to retrieve all the MyISAM tables in your database.

Replace value of the name_of_your_db variable with your database name.

SET @DATABASE_NAME = 'name_of_your_db';

SELECT  CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements
FROM    information_schema.tables AS tb
WHERE   table_schema = @DATABASE_NAME
AND     `ENGINE` = 'MyISAM'
AND     `TABLE_TYPE` = 'BASE TABLE'
ORDER BY table_name DESC;

Then, copy the output and run as a new SQL query.

"Uncaught SyntaxError: Cannot use import statement outside a module" when importing ECMAScript 6

Adding the why this occurs and more possible cause. A lot of interfaces still do not understand ES6 Javascript syntax/features, hence there is need for Es6 to be compiled to ES5 whenever it is used in any file or project. The possible reasons for the SyntaxError: Cannot use import statement outside a module error is you are trying to run the file independently, you are yet to install and set up an Es6 compiler such as Babel or the path of the file in your runscript is wrong/not the compiled file. If you will want to continue without a compiler the best possible solution is to use ES5 syntax which in your case would be var ms = require(./ms.js); this can later be updated as appropriate or better still setup your compiler and ensure your file/project is compiled before running and also ensure your run script is running the compiled file usually named dist, build or whatever you named it and the path to the compiled file in your runscript is correct.

How to list files and folder in a dir (PHP)

//path to directory to scan
$directory = "../data/team/";

//get all text files with a .txt extension.
$texts = glob($directory . "*.txt");

//print each file name
foreach($texts as $text)
{
    echo $text;
}

How do I import a sql data file into SQL Server?

There is no such thing as importing in MS SQL. I understand what you mean. It is so simple. Whenever you get/have a something.SQL file, you should just double click and it will directly open in your MS SQL Studio.

How to set Java classpath in Linux?

You have to use ':' colon instead of ';' semicolon.

As it stands now you try to execute the jar file which has not the execute bit set, hence the Permission denied.

And the variable must be CLASSPATH not classpath.

Javascript code for showing yesterday's date and todays date

Get yesterday date in javascript

You have to run code and check it output

_x000D_
_x000D_
    var today = new Date();_x000D_
    var yesterday = new Date(today);_x000D_
    _x000D_
    yesterday.setDate(today.getDate() - 1);_x000D_
    console.log("Original Date : ",yesterday);_x000D_
_x000D_
    const monthNames = [_x000D_
  "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"_x000D_
];_x000D_
    var month = today.getMonth() + 1_x000D_
    yesterday = yesterday.getDate() + ' ' + monthNames[month] + ' ' + yesterday.getFullYear()_x000D_
   _x000D_
    console.log("Modify Date : ",yesterday);
_x000D_
_x000D_
_x000D_

Injecting @Autowired private field during testing

Look at this link

Then write your test case as

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration({"/applicationContext.xml"})
public class MyLauncherTest{

@Resource
private MyLauncher myLauncher ;

   @Test
   public void someTest() {
       //test code
   }
}

Scrolling to an Anchor using Transition/CSS3

I implemented the answer suggested by @user18490 but ran into two problems:

  • First bouncing when user clicks on several tabs/links multiple times in short succession
  • Second, the undefined error mentioned by @krivar

I developed the following class to get around the mentioned problems, and it works fine:

export class SScroll{
    constructor(){
        this.delay=501      //ms
        this.duration=500   //ms
        this.lastClick=0
    }

    lastClick
    delay
    duration

    scrollTo=(destID)=>{
        /* To prevent "bounce" */
        /* https://stackoverflow.com/a/28610565/3405291 */
        if(this.lastClick>=(Date.now()-this.delay)){return}
        this.lastClick=Date.now()

        const dest=document.getElementById(destID)
        const to=dest.offsetTop
        if(document.body.scrollTop==to){return}
        const diff=to-document.body.scrollTop
        const scrollStep=Math.PI / (this.duration/10)
        let count=0
        let currPos
        const start=window.pageYOffset
        const scrollInterval=setInterval(()=>{
            if(document.body.scrollTop!=to){
                count++
                currPos=start+diff*(.5-.5*Math.cos(count*scrollStep))
                document.body.scrollTop=currPos
            }else{clearInterval(scrollInterval)}
        },10)
    }
}

UPDATE

There is a problem with Firefox as mentioned here. Therefore, to make it work on Firefox, I implemented the following code. It works fine on Chromium-based browsers and also Firefox.

export class SScroll{
    constructor(){
        this.delay=501      //ms
        this.duration=500   //ms
        this.lastClick=0
    }
    lastClick
    delay
    duration
    scrollTo=(destID)=>{
        /* To prevent "bounce" */
        /* https://stackoverflow.com/a/28610565/3405291 */
        if(this.lastClick>=(Date.now()-this.delay)){return}

        this.lastClick=Date.now()
        const dest=document.getElementById(destID)
        const to=dest.offsetTop
        if((document.body.scrollTop || document.documentElement.scrollTop || 0)==to){return}

        const diff=to-(document.body.scrollTop || document.documentElement.scrollTop || 0)
        const scrollStep=Math.PI / (this.duration/10)
        let count=0
        let currPos
        const start=window.pageYOffset
        const scrollInterval=setInterval(()=>{
            if((document.body.scrollTop || document.documentElement.scrollTop || 0)!=to){
                count++
                currPos=start+diff*(.5-.5*Math.cos(count*scrollStep))
                /* https://stackoverflow.com/q/28633221/3405291 */
                /* To support both Chromium-based and Firefox */
                document.body.scrollTop=currPos
                document.documentElement.scrollTop=currPos
            }else{clearInterval(scrollInterval)}
        },10)
    }
}

Maximum size of a varchar(max) variable

EDIT: After further investigation, my original assumption that this was an anomaly (bug?) of the declare @var datatype = value syntax is incorrect.

I modified your script for 2005 since that syntax is not supported, then tried the modified version on 2008. In 2005, I get the Attempting to grow LOB beyond maximum allowed size of 2147483647 bytes. error message. In 2008, the modified script is still successful.

declare @KMsg varchar(max); set @KMsg = REPLICATE('a',1024);
declare @MMsg varchar(max); set @MMsg = REPLICATE(@KMsg,1024);
declare @GMsg varchar(max); set @GMsg = REPLICATE(@MMsg,1024);
declare @GGMMsg varchar(max); set @GGMMsg = @GMsg + @GMsg + @MMsg;
select LEN(@GGMMsg)

mongodb group values by multiple fields

TLDR Summary

In modern MongoDB releases you can brute force this with $slice just off the basic aggregation result. For "large" results, run parallel queries instead for each grouping ( a demonstration listing is at the end of the answer ), or wait for SERVER-9377 to resolve, which would allow a "limit" to the number of items to $push to an array.

db.books.aggregate([
    { "$group": {
        "_id": {
            "addr": "$addr",
            "book": "$book"
        },
        "bookCount": { "$sum": 1 }
    }},
    { "$group": {
        "_id": "$_id.addr",
        "books": { 
            "$push": { 
                "book": "$_id.book",
                "count": "$bookCount"
            },
        },
        "count": { "$sum": "$bookCount" }
    }},
    { "$sort": { "count": -1 } },
    { "$limit": 2 },
    { "$project": {
        "books": { "$slice": [ "$books", 2 ] },
        "count": 1
    }}
])

MongoDB 3.6 Preview

Still not resolving SERVER-9377, but in this release $lookup allows a new "non-correlated" option which takes an "pipeline" expression as an argument instead of the "localFields" and "foreignFields" options. This then allows a "self-join" with another pipeline expression, in which we can apply $limit in order to return the "top-n" results.

db.books.aggregate([
  { "$group": {
    "_id": "$addr",
    "count": { "$sum": 1 }
  }},
  { "$sort": { "count": -1 } },
  { "$limit": 2 },
  { "$lookup": {
    "from": "books",
    "let": {
      "addr": "$_id"
    },
    "pipeline": [
      { "$match": { 
        "$expr": { "$eq": [ "$addr", "$$addr"] }
      }},
      { "$group": {
        "_id": "$book",
        "count": { "$sum": 1 }
      }},
      { "$sort": { "count": -1  } },
      { "$limit": 2 }
    ],
    "as": "books"
  }}
])

The other addition here is of course the ability to interpolate the variable through $expr using $match to select the matching items in the "join", but the general premise is a "pipeline within a pipeline" where the inner content can be filtered by matches from the parent. Since they are both "pipelines" themselves we can $limit each result separately.

This would be the next best option to running parallel queries, and actually would be better if the $match were allowed and able to use an index in the "sub-pipeline" processing. So which is does not use the "limit to $push" as the referenced issue asks, it actually delivers something that should work better.


Original Content

You seem have stumbled upon the top "N" problem. In a way your problem is fairly easy to solve though not with the exact limiting that you ask for:

db.books.aggregate([
    { "$group": {
        "_id": {
            "addr": "$addr",
            "book": "$book"
        },
        "bookCount": { "$sum": 1 }
    }},
    { "$group": {
        "_id": "$_id.addr",
        "books": { 
            "$push": { 
                "book": "$_id.book",
                "count": "$bookCount"
            },
        },
        "count": { "$sum": "$bookCount" }
    }},
    { "$sort": { "count": -1 } },
    { "$limit": 2 }
])

Now that will give you a result like this:

{
    "result" : [
            {
                    "_id" : "address1",
                    "books" : [
                            {
                                    "book" : "book4",
                                    "count" : 1
                            },
                            {
                                    "book" : "book5",
                                    "count" : 1
                            },
                            {
                                    "book" : "book1",
                                    "count" : 3
                            }
                    ],
                    "count" : 5
            },
            {
                    "_id" : "address2",
                    "books" : [
                            {
                                    "book" : "book5",
                                    "count" : 1
                            },
                            {
                                    "book" : "book1",
                                    "count" : 2
                            }
                    ],
                    "count" : 3
            }
    ],
    "ok" : 1
}

So this differs from what you are asking in that, while we do get the top results for the address values the underlying "books" selection is not limited to only a required amount of results.

This turns out to be very difficult to do, but it can be done though the complexity just increases with the number of items you need to match. To keep it simple we can keep this at 2 matches at most:

db.books.aggregate([
    { "$group": {
        "_id": {
            "addr": "$addr",
            "book": "$book"
        },
        "bookCount": { "$sum": 1 }
    }},
    { "$group": {
        "_id": "$_id.addr",
        "books": { 
            "$push": { 
                "book": "$_id.book",
                "count": "$bookCount"
            },
        },
        "count": { "$sum": "$bookCount" }
    }},
    { "$sort": { "count": -1 } },
    { "$limit": 2 },
    { "$unwind": "$books" },
    { "$sort": { "count": 1, "books.count": -1 } },
    { "$group": {
        "_id": "$_id",
        "books": { "$push": "$books" },
        "count": { "$first": "$count" }
    }},
    { "$project": {
        "_id": {
            "_id": "$_id",
            "books": "$books",
            "count": "$count"
        },
        "newBooks": "$books"
    }},
    { "$unwind": "$newBooks" },
    { "$group": {
      "_id": "$_id",
      "num1": { "$first": "$newBooks" }
    }},
    { "$project": {
        "_id": "$_id",
        "newBooks": "$_id.books",
        "num1": 1
    }},
    { "$unwind": "$newBooks" },
    { "$project": {
        "_id": "$_id",
        "num1": 1,
        "newBooks": 1,
        "seen": { "$eq": [
            "$num1",
            "$newBooks"
        ]}
    }},
    { "$match": { "seen": false } },
    { "$group":{
        "_id": "$_id._id",
        "num1": { "$first": "$num1" },
        "num2": { "$first": "$newBooks" },
        "count": { "$first": "$_id.count" }
    }},
    { "$project": {
        "num1": 1,
        "num2": 1,
        "count": 1,
        "type": { "$cond": [ 1, [true,false],0 ] }
    }},
    { "$unwind": "$type" },
    { "$project": {
        "books": { "$cond": [
            "$type",
            "$num1",
            "$num2"
        ]},
        "count": 1
    }},
    { "$group": {
        "_id": "$_id",
        "count": { "$first": "$count" },
        "books": { "$push": "$books" }
    }},
    { "$sort": { "count": -1 } }
])

So that will actually give you the top 2 "books" from the top two "address" entries.

But for my money, stay with the first form and then simply "slice" the elements of the array that are returned to take the first "N" elements.


Demonstration Code

The demonstration code is appropriate for usage with current LTS versions of NodeJS from v8.x and v10.x releases. That's mostly for the async/await syntax, but there is nothing really within the general flow that has any such restriction, and adapts with little alteration to plain promises or even back to plain callback implementation.

index.js

const { MongoClient } = require('mongodb');
const fs = require('mz/fs');

const uri = 'mongodb://localhost:27017';

const log = data => console.log(JSON.stringify(data, undefined, 2));

(async function() {

  try {
    const client = await MongoClient.connect(uri);

    const db = client.db('bookDemo');
    const books = db.collection('books');

    let { version } = await db.command({ buildInfo: 1 });
    version = parseFloat(version.match(new RegExp(/(?:(?!-).)*/))[0]);

    // Clear and load books
    await books.deleteMany({});

    await books.insertMany(
      (await fs.readFile('books.json'))
        .toString()
        .replace(/\n$/,"")
        .split("\n")
        .map(JSON.parse)
    );

    if ( version >= 3.6 ) {

    // Non-correlated pipeline with limits
      let result = await books.aggregate([
        { "$group": {
          "_id": "$addr",
          "count": { "$sum": 1 }
        }},
        { "$sort": { "count": -1 } },
        { "$limit": 2 },
        { "$lookup": {
          "from": "books",
          "as": "books",
          "let": { "addr": "$_id" },
          "pipeline": [
            { "$match": {
              "$expr": { "$eq": [ "$addr", "$$addr" ] }
            }},
            { "$group": {
              "_id": "$book",
              "count": { "$sum": 1 },
            }},
            { "$sort": { "count": -1 } },
            { "$limit": 2 }
          ]
        }}
      ]).toArray();

      log({ result });
    }

    // Serial result procesing with parallel fetch

    // First get top addr items
    let topaddr = await books.aggregate([
      { "$group": {
        "_id": "$addr",
        "count": { "$sum": 1 }
      }},
      { "$sort": { "count": -1 } },
      { "$limit": 2 }
    ]).toArray();

    // Run parallel top books for each addr
    let topbooks = await Promise.all(
      topaddr.map(({ _id: addr }) =>
        books.aggregate([
          { "$match": { addr } },
          { "$group": {
            "_id": "$book",
            "count": { "$sum": 1 }
          }},
          { "$sort": { "count": -1 } },
          { "$limit": 2 }
        ]).toArray()
      )
    );

    // Merge output
    topaddr = topaddr.map((d,i) => ({ ...d, books: topbooks[i] }));
    log({ topaddr });

    client.close();

  } catch(e) {
    console.error(e)
  } finally {
    process.exit()
  }

})()

books.json

{ "addr": "address1",  "book": "book1"  }
{ "addr": "address2",  "book": "book1"  }
{ "addr": "address1",  "book": "book5"  }
{ "addr": "address3",  "book": "book9"  }
{ "addr": "address2",  "book": "book5"  }
{ "addr": "address2",  "book": "book1"  }
{ "addr": "address1",  "book": "book1"  }
{ "addr": "address15", "book": "book1"  }
{ "addr": "address9",  "book": "book99" }
{ "addr": "address90", "book": "book33" }
{ "addr": "address4",  "book": "book3"  }
{ "addr": "address5",  "book": "book1"  }
{ "addr": "address77", "book": "book11" }
{ "addr": "address1",  "book": "book1"  }

iFrame Height Auto (CSS)

I had this same issue but found the following that works great:

The key to creating a responsive YouTube embed is with padding and a container element, which allows you to give it a fixed aspect ratio. You can also use this technique with most other iframe-based embeds, such as slideshows.

Here is what a typical YouTube embed code looks like, with fixed width and height:

 <iframe width="560" height="315" src="//www.youtube.com/embed/yCOY82UdFrw" 
 frameborder="0" allowfullscreen></iframe>

It would be nice if we could just give it a 100% width, but it won't work as the height remains fixed. What you need to do is wrap it in a container like so (note the class names and removal of the width and height):

 <div class="container">
 <iframe src="//www.youtube.com/embed/yCOY82UdFrw" 
 frameborder="0" allowfullscreen class="video"></iframe>
 </div>

And use the following CSS:

 .container {
    position: relative;
     width: 100%;
     height: 0;
     padding-bottom: 56.25%;
 }
 .video {
     position: absolute;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
 }

Here is the page I found the solution on:

https://www.h3xed.com/web-development/how-to-make-a-responsive-100-width-youtube-iframe-embed

Depending on your aspect ratio, you will probably need to adjust the padding-bottom: 56.25%; to get the height right.

How to use PrintWriter and File classes in Java?

Java doesn't normally accept "/" to use in defining a file directory, so try this:

 File file = new File ("C:\\Users\\user\\workspace\\FileTester\\myFile.txt");

If the file doesn't exist do:

 try {
      file.createNewFile();
 }
 catch (IOException e) {
 e.printStackTrace();
 }

Creating a SearchView that looks like the material design guidelines

It is actually quite easy to do this, if you are using android.support.v7 library.

Step - 1

Declare a menu item

<item android:id="@+id/action_search"
    android:title="Search"
    android:icon="@drawable/abc_ic_search_api_mtrl_alpha"
    app:showAsAction="ifRoom|collapseActionView"
    app:actionViewClass="android.support.v7.widget.SearchView" />

Step - 2

Extend AppCompatActivity and in the onCreateOptionsMenu setup the SearchView.

import android.support.v7.widget.SearchView;

...

public class YourActivity extends AppCompatActivity {

    ...

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.menu_home, menu);
        // Retrieve the SearchView and plug it into SearchManager
        final SearchView searchView = (SearchView) MenuItemCompat.getActionView(menu.findItem(R.id.action_search));
        SearchManager searchManager = (SearchManager) getSystemService(SEARCH_SERVICE);
        searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
        return true;
    }

    ... 

}

Result

enter image description here

enter image description here

Print all key/value pairs in a Java ConcurrentHashMap

You can do something like

Iterator iterator = map.keySet().iterator();

while (iterator.hasNext()) {
   String key = iterator.next().toString();
   Integer value = map.get(key);

   System.out.println(key + " " + value);
}

Here 'map' is your concurrent HashMap.

How to prevent page scrolling when scrolling a DIV element?

I think it's possible to cancel the mousescroll event sometimes: http://jsfiddle.net/rudiedirkx/F8qSq/show/

$elem.on('wheel', function(e) {
    var d = e.originalEvent.deltaY,
        dir = d < 0 ? 'up' : 'down',
        stop = (dir == 'up' && this.scrollTop == 0) || 
               (dir == 'down' && this.scrollTop == this.scrollHeight-this.offsetHeight);
    stop && e.preventDefault();
});

Inside the event handler, you'll need to know:

  • scrolling direction
    d = e.originalEvent.deltaY, dir = d < 0 ? 'up' : 'down' because a positive number means scrolling down
  • scroll position
    scrollTop for top, scrollHeight - scrollTop - offsetHeight for bottom

If you're

  • scrolling up, and top = 0, or
  • scrolling down, and bottom = 0,

cancel the event: e.preventDefault() (and maybe even e.stopPropagation()).

I think it's better to not override the browser's scrolling behaviour. Only cancel it when applicable.

It's probablt not perfectly xbrowser, but it can't be very hard. Maybe Mac's dual scroll direction is tricky though...

How to convert empty spaces into null values, using SQL Server?

Maybe something like this?

UPDATE [MyTable]
SET [SomeField] = NULL
WHERE [SomeField] is not NULL
AND LEN(LTRIM(RTRIM([SomeField]))) = 0

Python Iterate Dictionary by Index

Since you want to iterate in order, you can use sorted:

for k, v in sorted(dict.items()):
    print k,v

VBA ADODB excel - read data from Recordset

I am surprised that the connection string works for you, because it is missing a semi-colon. Set is only used with objects, so you would not say Set strNaam.

Set cn = CreateObject("ADODB.Connection")
With cn
 .Provider = "Microsoft.Jet.OLEDB.4.0"
  .ConnectionString = "Data Source=D:\test.xls " & _
  ";Extended Properties=""Excel 8.0;HDR=Yes;"""
.Open
End With
strQuery = "SELECT * FROM [Sheet1$E36:E38]"
Set rs = cn.Execute(strQuery)
Do While Not rs.EOF
  For i = 0 To rs.Fields.Count - 1
    Debug.Print rs.Fields(i).Name, rs.Fields(i).Value
    strNaam = rs.Fields(0).Value
  Next
  rs.MoveNext
Loop
rs.Close

There are other ways, depending on what you want to do, such as GetString (GetString Method Description).

How can I compile LaTeX in UTF8?

I'm not sure whether I got your problem but maybe it helps if you store the source using a UTF-8 encoding.

I'm also using \usepackage[utf8]{inputenc} in my LaTeX sources and by storing the files as UTF-8 files everything works just peachy.

Where are Docker images stored on the host machine?

When using Docker for Mac Application, it appears that the containers are stored within the VM located at:

~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/Docker.qcow2

UPDATE (Courtesy of mmorin):

As of Jan 15 2019 it seems there is only this file:

~/Library/Containers/com.docker.docker/Data/vms/0/Docker.raw

that contains the Docker Disk and all the images and containers within it.

How can I add a username and password to Jenkins?

Assuming you have Manage Jenkins > Configure Global Security > Enable Security and Jenkins Own User Database checked you would go to:

  • Manage Jenkins > Manage Users > Create User

How to stop INFO messages displaying on spark console?

Adding the following to the PySpark did the job for me:

self.spark.sparkContext.setLogLevel("ERROR")

self.spark is the spark session (self.spark = spark_builder.getOrCreate())

Your project path contains non-ASCII characters android studio

The best solution to your problem is to move your project folder to other directory with no non-ASCII characters and blank spaces.

For example ?:\Android\PROJECT-FOLDER.

You can create the directory in C:\ using the name that you want.

how do I get eclipse to use a different compiler version for Java?

First off, are you setting your desired JRE or your desired JDK?

Even if your Eclipse is set up properly, there might be a wacky project-specific setting somewhere. You can open up a context menu on a given Java project in the Project Explorer and select Properties > Java Compiler to check on that.

If none of that helps, leave a comment and I'll take another look.

Padding between ActionBar's home icon and title

I solved this problem by using custom Navigation layout

Using it you can customize anything in title on action bar:

build.gradle

dependencies {
    compile 'com.android.support:appcompat-v7:21.0.+'
    ...
}

AndroidManifest.xml

<application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name">
        <activity
            android:name=".MainActivity"
            android:theme="@style/ThemeName">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
</application>

styles.xml

<style name="ThemeName" parent="Theme.AppCompat.Light">
   <item name="actionBarStyle">@style/ActionBar</item>
   <item name="android:actionBarStyle" tools:ignore="NewApi">@style/ActionBar</item>

<style name="ActionBar" parent="Widget.AppCompat.ActionBar">
   <item name="displayOptions">showCustom</item>
   <item name="android:displayOptions" tools:ignore="NewApi">showCustom</item>

    <item name="customNavigationLayout">@layout/action_bar</item>
   <item name="android:customNavigationLayout" tools:ignore="NewApi">@layout/action_bar</item>

    <item name="background">@color/android:white</item>
   <item name="android:background">@color/android:white</item>

action_bar.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
          android:id="@+id/action_bar_title"
          android:layout_width="wrap_content"
          android:layout_height="wrap_content"
          android:gravity="center_vertical"
          android:drawableLeft="@drawable/ic_launcher"
          android:drawablePadding="10dp"
          android:textSize="20sp"
          android:textColor="@android:color/black"
          android:text="@string/app_name"/>

How to collapse blocks of code in Eclipse?

To collapse all code blocks Ctrl + Shift+ /

To expand all code blocks Ctrl + Shift+ *

pydev:

To collapse all code blocks : Ctrl + 0

To collapse all code blocks : Ctrl + 9

Is there a way to collapse all code blocks in Eclipse?

by @partizanos and @bummi

validation of input text field in html using javascript

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
        <title>Validation</title>
        <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
        <script type="text/javascript">
            var tags = document.getElementsByTagName("input");
            var radiotags = document.getElementsByName("gender");
            var compareValidator = ['compare'];
            var formtag = document.getElementsByTagName("form");
            function validation(){
                for(var i=0;i<tags.length;i++){
                    var tagid = tags[i].id;
                    var tagval = tags[i].value;
                    var tagtit = tags[i].title;
                    var tagclass = tags[i].className;
                    //Validation for Textbox Start
                    if(tags[i].type == "text"){
                        if(tagval == "" || tagval == null){
                            var lbl = $(tags[i]).prev().text();
                            lbl = lbl.replace(/ : /g,'')
                            //alert("Please Enter "+lbl);
                            $(".span"+tagid).remove();
                            $("#"+tagid).after("<span style='color:red;' class='span"+tagid+"'>Please Enter "+lbl+"</span>");
                            $("#"+tagid).focus();
                            //return false;
                        }
                        else if(tagval != "" || tagval != null){
                            $(".span"+tagid).remove();
                        }
                        //Validation for compare text in two text boxes Start
                        //put two tags with same class name and put class name in compareValidator.
                        for(var j=0;j<compareValidator.length;j++){
                            if((tagval != "") && (tagclass.indexOf(compareValidator[j]) != -1)){
                                if(($('.'+compareValidator[j]).first().val()) != ($('.'+compareValidator[j]).last().val())){
                                    $("."+compareValidator[j]+":last").after("<span style='color:red;' class='span"+tagid+"'>Invalid Text</span>");
                                    $("span").prev("span").remove();
                                    $("."+compareValidator[j]+":last").focus();
                                    //return false;
                                }
                            }
                        }
                        //Validation for compare text in two text boxes End
                        //Validation for Email Start
                        if((tagval != "") && (tagclass.indexOf('email') != -1)){
                        //enter class = email where you want to use email validator
                            var reg = /^\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*$/
                            if (reg.test(tagval)){
                                $(".span"+tagid).remove();
                                return true; 
                            }
                            else{
                                $(".span"+tagid).remove();
                                $("#"+tagid).after("<span style='color:red;' class='span"+tagid+"'>Email is Invalid</span>");
                                $("#"+tagid).focus();
                                return false;
                            }
                        }
                        //Validation for Email End
                    }
                    //Validation for Textbox End
                    //Validation for Radio Start
                    else if(tags[i].type == "radio"){
                    //enter class = gender where you want to use gender validator
                        if((radiotags[0].checked == false) && (radiotags[1].checked == false)){
                            $(".span"+tagid).remove();
                            //$("#"+tagid").after("<span style='color:red;' class='span"+tagid+"'>Please Select Your Gender </span>");
                            $(".gender:last").next().after("<span style='color:red;' class='span"+tagid+"'> Please Select Your Gender</span>");
                            $("#"+tagid).focus();
                            i += 1;
                        }
                        else{
                            $(".span"+tagid).remove();
                        }
                    }
                    //Validation for Radio End              
                    else{

                    }
                }
                //return false;
            }
            function Validate(){
               if(!validation()){
                    return false;
                }
                return true;
            }
            function onloadevents(){
                tags[tags.length -1].onclick = function(){
                    //return Validate();
                }
                for(var j=0;j<formtag.length;j++){
                    formtag[j].onsubmit = function(){
                        return Validate();
                    }
                }
                for(var i=0;i<tags.length;i++){
                    var tagid = tags[i].id;
                    var tagval = tags[i].value;
                    var tagtit = tags[i].title;
                    var tagclass = tags[i].className;
                    if((tags[i].type == "text") && (tagclass.indexOf('numeric') != -1)){
                        //enter class = numeric where you want to use numeric validator
                        document.getElementById(tagid).onkeypress = function(){
                            numeric(event);
                        }
                    }
                }
            }
            function numeric(event){
                var KeyBoardCode = (event.which) ? event.which : event.keyCode; 
                if (KeyBoardCode > 31 && (KeyBoardCode < 48 || KeyBoardCode > 57)){
                    event.preventDefault();
                    $(".spannum").remove();
                    //$(".numeric").after("<span class='spannum'>Numeric Keys Please</span>");
                    //$(".numeric").focus();
                    return false;
                }
                    $(".spannum").remove();
                    return true;
            }
            if (document.addEventListener) {
              document.addEventListener("DOMContentLoaded", onloadevents, false);
            }
            //window.onload = onloadevents;
        </script>
    </head>
    <body>
        <form method="post">
            <label for="fname">Test 1 : </label><input type="text" title="Test 1" id="fname" class="form1"><br>
            <label for="fname1">Test 2 : </label><input type="text" title="Test 2" id="fname1" class="form1 compare"><br>
            <label for="fname2">Test 3 : </label><input type="text" title="Test 3" id="fname2" class="form1 compare"><br>
            <label for="gender">Gender : </label>
            <input type="radio" title="Male" id="fname3" class="gender" name="gender" value="Male"><label for="gender">Male</label>
            <input type="radio" title="Female" id="fname4" class="gender" name="gender" value="Female"><label for="gender">Female</label><br>
            <label for="fname5">Mobile : </label><input type="text" title="Mobile" id="fname5" class="numeric"><br>
            <label for="fname6">Email : </label><input type="text" title="Email" id="fname6" class="email"><br>
            <input type="submit" id="sub" value="Submit">
        </form>
    </body>
</html>

Convert IEnumerable to DataTable

To all:

Note that the accepted answer has a bug in it relating to nullable types and the DataTable. The fix is available at the linked site (http://www.chinhdo.com/20090402/convert-list-to-datatable/) or in my modified code below:

    ///###############################################################
    /// <summary>
    /// Convert a List to a DataTable.
    /// </summary>
    /// <remarks>
    /// Based on MIT-licensed code presented at http://www.chinhdo.com/20090402/convert-list-to-datatable/ as "ToDataTable"
    /// <para/>Code modifications made by Nick Campbell.
    /// <para/>Source code provided on this web site (chinhdo.com) is under the MIT license.
    /// <para/>Copyright © 2010 Chinh Do
    /// <para/>Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
    /// <para/>The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
    /// <para/>THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    /// <para/>(As per http://www.chinhdo.com/20080825/transactional-file-manager/)
    /// </remarks>
    /// <typeparam name="T">Type representing the type to convert.</typeparam>
    /// <param name="l_oItems">List of requested type representing the values to convert.</param>
    /// <returns></returns>
    ///###############################################################
    /// <LastUpdated>February 15, 2010</LastUpdated>
    public static DataTable ToDataTable<T>(List<T> l_oItems) {
        DataTable oReturn = new DataTable(typeof(T).Name);
        object[] a_oValues;
        int i;

            //#### Collect the a_oProperties for the passed T
        PropertyInfo[] a_oProperties = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

            //#### Traverse each oProperty, .Add'ing each .Name/.BaseType into our oReturn value
            //####     NOTE: The call to .BaseType is required as DataTables/DataSets do not support nullable types, so it's non-nullable counterpart Type is required in the .Column definition
        foreach(PropertyInfo oProperty in a_oProperties) {
            oReturn.Columns.Add(oProperty.Name, BaseType(oProperty.PropertyType));
        }

            //#### Traverse the l_oItems
        foreach (T oItem in l_oItems) {
                //#### Collect the a_oValues for this loop
            a_oValues = new object[a_oProperties.Length];

                //#### Traverse the a_oProperties, populating each a_oValues as we go
            for (i = 0; i < a_oProperties.Length; i++) {
                a_oValues[i] = a_oProperties[i].GetValue(oItem, null);
            }

                //#### .Add the .Row that represents the current a_oValues into our oReturn value
            oReturn.Rows.Add(a_oValues);
        }

            //#### Return the above determined oReturn value to the caller
        return oReturn;
    }

    ///###############################################################
    /// <summary>
    /// Returns the underlying/base type of nullable types.
    /// </summary>
    /// <remarks>
    /// Based on MIT-licensed code presented at http://www.chinhdo.com/20090402/convert-list-to-datatable/ as "GetCoreType"
    /// <para/>Code modifications made by Nick Campbell.
    /// <para/>Source code provided on this web site (chinhdo.com) is under the MIT license.
    /// <para/>Copyright © 2010 Chinh Do
    /// <para/>Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
    /// <para/>The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
    /// <para/>THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
    /// <para/>(As per http://www.chinhdo.com/20080825/transactional-file-manager/)
    /// </remarks>
    /// <param name="oType">Type representing the type to query.</param>
    /// <returns>Type representing the underlying/base type.</returns>
    ///###############################################################
    /// <LastUpdated>February 15, 2010</LastUpdated>
    public static Type BaseType(Type oType) {
            //#### If the passed oType is valid, .IsValueType and is logicially nullable, .Get(its)UnderlyingType
        if (oType != null && oType.IsValueType &&
            oType.IsGenericType && oType.GetGenericTypeDefinition() == typeof(Nullable<>)
        ) {
            return Nullable.GetUnderlyingType(oType);
        }
            //#### Else the passed oType was null or was not logicially nullable, so simply return the passed oType
        else {
            return oType;
        }
    }

Note that both of these example are NOT extension methods like the example above.

Lastly... apologies for my extensive/excessive comments (I had a anal/mean prof that beat it into me! ;)

How to add noise (Gaussian/salt and pepper etc) to image in Python with OpenCV

I don't know is there any method in Python API.But you can use this simple code to add Salt-and-Pepper noise to an image.

import numpy as np
import random
import cv2

def sp_noise(image,prob):
    '''
    Add salt and pepper noise to image
    prob: Probability of the noise
    '''
    output = np.zeros(image.shape,np.uint8)
    thres = 1 - prob 
    for i in range(image.shape[0]):
        for j in range(image.shape[1]):
            rdn = random.random()
            if rdn < prob:
                output[i][j] = 0
            elif rdn > thres:
                output[i][j] = 255
            else:
                output[i][j] = image[i][j]
    return output

image = cv2.imread('image.jpg',0) # Only for grayscale image
noise_img = sp_noise(image,0.05)
cv2.imwrite('sp_noise.jpg', noise_img)

How to extract numbers from a string and get an array of ints?

Pattern p = Pattern.compile("-?\\d+");
Matcher m = p.matcher("There are more than -2 and less than 12 numbers here");
while (m.find()) {
  System.out.println(m.group());
}

... prints -2 and 12.


-? matches a leading negative sign -- optionally. \d matches a digit, and we need to write \ as \\ in a Java String though. So, \d+ matches 1 or more digits.