Programs & Examples On #Iorderedenumerable

How to get last key in an array?

Although end() seems to be the easiest, it's not the fastest. The faster, and much stronger alternative is array_slice():

$lastKey = key(array_slice($array, -1, 1, true));

As the tests say, on an array with 500000 elements, it is almost 7x faster!

how to make label visible/invisible?

You are looking for display:

document.getElementById("endTimeLabel").style.display = 'none';
document.getElementById("endTimeLabel").style.display = 'block';

Edit: You could also easily reuse your validation function.

HTML:

<span id="startDateLabel">Start date/time: </span>
<input id="startDateStr" name="startDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
<button id="startDateCalendarTrigger">...</button>
<input id="startDateTime" type="text" size="8" name="startTime" value="12:00 AM" onchange="validateHHMM(this.value, 'startTimeLabel');"/>
<label id="startTimeLabel" class="errorMsg">Time must be entered in the format HH:MM AM/PM</label><br />

<span id="endDateLabel">End date/time: </span>
<input id="endDateStr" name="endDateStr" size="8" onchange="if (!formatDate(this,'USA')) {this.value = '';}" />
<button id="endDateCalendarTrigger">...</button>

<input id="endDateTime" type="text" size="8" name="endTime" value="12:00 AM" onchange="validateHHMM(this.value, 'endTimeLabel');"/>
<label id="endTimeLabel" class="errorMsg">Time must be entered in the format HH:MM AM/PM</label>

Javascript:

function validateHHMM(value, message) {
    var isValid = /^(0?[1-9]|1[012])(:[0-5]\d) [APap][mM]$/.test(value);

    if (isValid) {
        document.getElementById(message).style.display = "none";
    }else {
        document.getElementById(message).style.display= "inline";
    }

    return isValid;
}

Live DEMO

Online SQL syntax checker conforming to multiple databases

I am willing to bet some of my reputation that there is no such thing.

Partially because if you are worried about cross-platform SQL compatibility, your best bet in turn is to abstract your database code with some API or ORM tool that handles these things for you, and is well supported, so will deal with newer database versions as they come out.

Exact kind of API available to you will be dependent on your programming language/platform. For example, PHP has Pear:DB and others, I personally have found quite nice Python's ORM features implemented in Django framework. I presume there should be some of these things available on other platforms as well.

How can I delete all Git branches which have been merged?

Let's say I have a remote named upstream and an origin (GitHub style, my fork is origin, upstream is upstream).

I don't want to delete ANY masters, HEAD, or anything from the upstream. I also don't want to delete the develop branch as that is our common branch we create PRs from.

List all remote branches, filtered by ones that were merged:

git branch -r

Remove lines from that list that contain words I know are in branch names I don't want to remove:

sed '/develop\|master\|HEAD\|upstream/d'

Remove the remote name from the reference name (origin/somebranch becomes somebranch):

sed 's/.*\///'

Use xargs to call a one-liner:

xargs git push --delete origin

Pipe it all together you get:

git branch -r --merged | sed '/develop\|master\|HEAD\|upstream/d' |  sed 's/.*\///' | xargs git push --delete origin

This will leave me with only some branches that I have worked on, but have not merged. You can then remove them one by one as there shouldn't be too many.

Find branches you no longer want:

git branch -ar

Say you find branch1, branch2, and branch3 you want to delete:

git push --delete origin branch1 branch2 branch3

C++ cast to derived class

First of all - prerequisite for downcast is that object you are casting is of the type you are casting to. Casting with dynamic_cast will check this condition in runtime (provided that casted object has some virtual functions) and throw bad_cast or return NULL pointer on failure. Compile-time casts will not check anything and will just lead tu undefined behaviour if this prerequisite does not hold.
Now analyzing your code:

DerivedType m_derivedType = m_baseType;

Here there is no casting. You are creating a new object of type DerivedType and try to initialize it with value of m_baseType variable.

Next line is not much better:

DerivedType m_derivedType = (DerivedType)m_baseType;

Here you are creating a temporary of DerivedType type initialized with m_baseType value.

The last line

DerivedType * m_derivedType = (DerivedType*) & m_baseType;

should compile provided that BaseType is a direct or indirect public base class of DerivedType. It has two flaws anyway:

  1. You use deprecated C-style cast. The proper way for such casts is
    static_cast<DerivedType *>(&m_baseType)
  2. The actual type of casted object is not of DerivedType (as it was defined as BaseType m_baseType; so any use of m_derivedType pointer will result in undefined behaviour.

find_spec_for_exe': can't find gem bundler (>= 0.a) (Gem::GemNotFoundException)

The problem in my case is that the Gemfile.lock file had a BUNDLED_WITH version of 1.16.1 and gem install bundler installed version 2.0.1, so there was a version mismatch when looking to right the folder

gem install bundler -v 1.16.1 fixed it

Of course, you can also change your Gemfile.lock's BUNDLED_WITH with last bundler version and use recent software, as Sam3000 suggests

Convert date from String to Date format in Dataframes

Since your main aim was to convert the type of a column in a DataFrame from String to Timestamp, I think this approach would be better.

import org.apache.spark.sql.functions.{to_date, to_timestamp}
val modifiedDF = DF.withColumn("Date", to_date($"Date", "MM/dd/yyyy"))

You could also use to_timestamp (I think this is available from Spark 2.x) if you require fine grained timestamp.

substring index range

public class SubstringExample
{
    public static void main(String[] args) 
    {
        String str="OOPs is a programming paradigm...";

        System.out.println(" Length is: " + str.length());

        System.out.println(" Substring is: " + str.substring(10, 30));
    }
}

Output:

length is: 31

Substring is: programming paradigm

Remove last item from array

say you have var arr = [1,0,2]

arr.splice(-1,1) will return to you array [1,0]; while arr.slice(-1,1) will return to you array [2];

ImportError: No module named Image

On a system with both Python 2 and 3 installed and with pip2-installed Pillow failing to provide Image, it is possible to install PIL for Python 2 in a way that will solve ImportError: No module named Image:

easy_install-2.7 --user PIL

or

sudo easy_install-2.7 PIL

Is "else if" faster than "switch() case"?

Switch is generally faster than a long list of ifs because the compiler can generate a jump table. The longer the list, the better a switch statement is over a series of if statements.

How to select rows where column value IS NOT NULL using CodeIgniter's ActiveRecord?

Much better to use following:

For is not null:

where('archived IS NOT NULL', null);

For is null:

where('archived', null);

Get pandas.read_csv to read empty values as empty string instead of nan

I was still confused after reading the other answers and comments. But the answer now seems simpler, so here you go.

Since Pandas version 0.9 (from 2012), you can read your csv with empty cells interpreted as empty strings by simply setting keep_default_na=False:

pd.read_csv('test.csv', keep_default_na=False)

This issue is more clearly explained in

That was fixed on on Aug 19, 2012 for Pandas version 0.9 in

How do I view executed queries within SQL Server Management Studio?

Run the following query from Management Studio on a running process:

DBCC inputbuffer( spid# )

This will return the SQL currently being run against the database for the SPID provided. Note that you need appropriate permissions to run this command.

This is better than running a trace since it targets a specific SPID. You can see if it's long running based on its CPUTime and DiskIO.

Example to get details of SPID 64:

DBCC inputbuffer(64)

How to send an object from one Android Activity to another using Intents?

We can send data one Activty1 to Activity2 with multiple ways like.
1- Intent
2- bundle
3- create an object and send through intent
.................................................
1 - Using intent
Pass the data through intent
Intent intentActivity1 = new Intent(Activity1.this, Activity2.class);
intentActivity1.putExtra("name", "Android");
startActivity(intentActivity1);
Get the data in Activity2 calss
Intent intent = getIntent();
if(intent.hasExtra("name")){
     String userName = getIntent().getStringExtra("name");
}
..................................................
2- Using Bundle
Intent intentActivity1 = new Intent(Activity1.this, Activity2.class);
Bundle bundle = new Bundle();
bundle.putExtra("name", "Android");
intentActivity1.putExtra(bundle);
startActivity(bundle);
Get the data in Activity2 calss
Intent intent = getIntent();
if(intent.hasExtra("name")){
     String userName = getIntent().getStringExtra("name");
}
..................................................
3-  Put your Object into Intent
Intent intentActivity1 = new Intent(Activity1.this, Activity2.class);
            intentActivity1.putExtra("myobject", myObject);
            startActivity(intentActivity1); 
 Receive object in the Activity2 Class
Intent intent = getIntent();
    Myobject obj  = (Myobject) intent.getSerializableExtra("myobject");

Sending a file over TCP sockets in Python

Remove below code

s.send("Hello server!")

because your sending s.send("Hello server!") to server, so your output file is somewhat more in size.

How can I use LTRIM/RTRIM to search and replace leading/trailing spaces?

To remove spaces... please use LTRIM/RTRIM

 LTRIM(String)
 RTRIM(String)

The String parameter that is passed to the functions can be a column name, a variable, a literal string or the output of a user defined function or scalar query.

SELECT LTRIM(' spaces at start')
SELECT RTRIM(FirstName) FROM Customers

Read more: http://rockingshani.blogspot.com/p/sq.html#ixzz33SrLQ4Wi

Easy way to convert Iterable to Collection

I use FluentIterable.from(myIterable).toList() a lot.

Unable to generate an explicit migration in entity framework

I had this problem too for a database that I knew was up to date when running Add-Migration. Solved by simply running the Add-Migration command a second time. Suspect a connectivity issue, as suggested by Robin Dorbell above.

Maven: The packaging for this project did not assign a file to the build artifact

This error shows up when using the maven-install-plugin version 3.0.0-M1 (or similar)

As already mentioned above and also here the following plug-in version works:

    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-install-plugin</artifactId>
        <version>2.5.2</version>
    </plugin>

CMake output/build directory

It sounds like you want an out of source build. There are a couple of ways you can create an out of source build.

  1. Do what you were doing, run

    cd /path/to/my/build/folder
    cmake /path/to/my/source/folder
    

    which will cause cmake to generate a build tree in /path/to/my/build/folder for the source tree in /path/to/my/source/folder.

    Once you've created it, cmake remembers where the source folder is - so you can rerun cmake on the build tree with

    cmake /path/to/my/build/folder
    

    or even

    cmake .
    

    if your current directory is already the build folder.

  2. For CMake 3.13 or later, use these options to set the source and build folders

    cmake -B/path/to/my/build/folder -S/path/to/my/source/folder
    
  3. For older CMake, use some undocumented options to set the source and build folders:

    cmake -B/path/to/my/build/folder -H/path/to/my/source/folder
    

    which will do exactly the same thing as (1), but without the reliance on the current working directory.

CMake puts all of its outputs in the build tree by default, so unless you are liberally using ${CMAKE_SOURCE_DIR} or ${CMAKE_CURRENT_SOURCE_DIR} in your cmake files, it shouldn't touch your source tree.

The biggest thing that can go wrong is if you have previously generated a build tree in your source tree (i.e. you have an in source build). Once you've done this the second part of (1) above kicks in, and cmake doesn't make any changes to the source or build locations. Thus, you cannot create an out-of-source build for a source directory with an in-source build. You can fix this fairly easily by removing (at a minimum) CMakeCache.txt from the source directory. There are a few other files (mostly in the CMakeFiles directory) that CMake generates that you should remove as well, but these won't cause cmake to treat the source tree as a build tree.

Since out-of-source builds are often more desirable than in-source builds, you might want to modify your cmake to require out of source builds:

# Ensures that we do an out of source build

MACRO(MACRO_ENSURE_OUT_OF_SOURCE_BUILD MSG)
     STRING(COMPARE EQUAL "${CMAKE_SOURCE_DIR}"
     "${CMAKE_BINARY_DIR}" insource)
     GET_FILENAME_COMPONENT(PARENTDIR ${CMAKE_SOURCE_DIR} PATH)
     STRING(COMPARE EQUAL "${CMAKE_SOURCE_DIR}"
     "${PARENTDIR}" insourcesubdir)
    IF(insource OR insourcesubdir)
        MESSAGE(FATAL_ERROR "${MSG}")
    ENDIF(insource OR insourcesubdir)
ENDMACRO(MACRO_ENSURE_OUT_OF_SOURCE_BUILD)

MACRO_ENSURE_OUT_OF_SOURCE_BUILD(
    "${CMAKE_PROJECT_NAME} requires an out of source build."
)

The above macro comes from a commonly used module called MacroOutOfSourceBuild. There are numerous sources for MacroOutOfSourceBuild.cmake on google but I can't seem to find the original and it's short enough to include here in full.

Unfortunately cmake has usually written a few files by the time the macro is invoked, so although it will stop you from actually performing the build you will still need to delete CMakeCache.txt and CMakeFiles.

You may find it useful to set the paths that binaries, shared and static libraries are written to - in which case see how do I make cmake output into a 'bin' dir? (disclaimer, I have the top voted answer on that question...but that's how I know about it).

Finding whether a point lies inside a rectangle or not

How is the rectangle represented? Three points? Four points? Point, sides and angle? Two points and a side? Something else? Without knowing that, any attempts to answer your question will have only purely academic value.

In any case, for any convex polygon (including rectangle) the test is very simple: check each edge of the polygon, assuming each edge is oriented in counterclockwise direction, and test whether the point lies to the left of the edge (in the left-hand half-plane). If all edges pass the test - the point is inside. If at least one fails - the point is outside.

In order to test whether the point (xp, yp) lies on the left-hand side of the edge (x1, y1) - (x2, y2), you just need to calculate

D = (x2 - x1) * (yp - y1) - (xp - x1) * (y2 - y1)

If D > 0, the point is on the left-hand side. If D < 0, the point is on the right-hand side. If D = 0, the point is on the line.


The previous version of this answer described a seemingly different version of left-hand side test (see below). But it can be easily shown that it calculates the same value.

... In order to test whether the point (xp, yp) lies on the left-hand side of the edge (x1, y1) - (x2, y2), you need to build the line equation for the line containing the edge. The equation is as follows

A * x + B * y + C = 0

where

A = -(y2 - y1)
B = x2 - x1
C = -(A * x1 + B * y1)

Now all you need to do is to calculate

D = A * xp + B * yp + C

If D > 0, the point is on the left-hand side. If D < 0, the point is on the right-hand side. If D = 0, the point is on the line.

However, this test, again, works for any convex polygon, meaning that it might be too generic for a rectangle. A rectangle might allow a simpler test... For example, in a rectangle (or in any other parallelogram) the values of A and B have the same magnitude but different signs for opposing (i.e. parallel) edges, which can be exploited to simplify the test.

Excel VBA Check if directory exists error

You can replace WB_parentfolder with something like "C:\". For me WB_parentfolder is grabbing the location of the current workbook. file_des_folder is the new folder i want. This goes through and creates as many folders as you need.

        folder1 = Left(file_des_folder, InStr(Len(WB_parentfolder) + 1, file_loc, "\"))
        Do While folder1 <> file_des_folder
            folder1 = Left(file_des_folder, InStr(Len(folder1) + 1, file_loc, "\"))
            If Dir(file_des_folder, vbDirectory) = "" Then      'create folder if there is not one
                MkDir folder1
            End If
        Loop

Error checking for NULL in VBScript

I will just add a blank ("") to the end of the variable and do the comparison. Something like below should work even when that variable is null. You can also trim the variable just in case of spaces.

If provider & "" <> "" Then 
    url = url & "&provider=" & provider 
End if

Live video streaming using Java?

Hi not an expert in streaming but my understanding is that it is included in th Java Media Framework JMF http://java.sun.com/javase/technologies/desktop/media/jmf/2.1.1/support-rtsp.html

Flex-box: Align last row to grid

One technique would be inserting a number of extra elements (as many as the max number of elements you ever expect to have in a row) that are given zero height. Space is still divided, but superfluous rows collapse to nothing:

http://codepen.io/dalgard/pen/Dbnus

_x000D_
_x000D_
body {_x000D_
  padding: 5%;_x000D_
}_x000D_
_x000D_
div {_x000D_
  overflow: hidden;_x000D_
  background-color: yellow;_x000D_
}_x000D_
_x000D_
ul {_x000D_
  display: flex;_x000D_
  flex-wrap: wrap;_x000D_
  margin: 0 -4px -4px 0;_x000D_
  list-style: none;_x000D_
  padding: 0;_x000D_
}_x000D_
_x000D_
li {_x000D_
  flex: 1 0 200px;_x000D_
  height: 200px;_x000D_
  border-right: 4px solid black;_x000D_
  border-bottom: 4px solid black;_x000D_
  background-color: deeppink;_x000D_
}_x000D_
li:empty {_x000D_
  height: 0;_x000D_
  border: none;_x000D_
}_x000D_
_x000D_
*,_x000D_
:before,_x000D_
:after {_x000D_
  box-sizing: border-box;_x000D_
}
_x000D_
<div>_x000D_
  <ul>_x000D_
    <li>a</li>_x000D_
    <li>b</li>_x000D_
    <li>c</li>_x000D_
    <li>d</li>_x000D_
    <li>e</li>_x000D_
    <li>f</li>_x000D_
    <li>g</li>_x000D_
    <li>h</li>_x000D_
    <li>i</li>_x000D_
    <li>j</li>_x000D_
    <li>k</li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
    <li></li>_x000D_
  </ul>_x000D_
</div>
_x000D_
_x000D_
_x000D_

In the future, this may become achievable through using multiple ::after(n).

css background image in a different folder from css

You are using a relative path. You should use the absolute path, url(/assets/css/style.css).

Add a scrollbar to a <textarea>

textarea {
    overflow-y: scroll; /* Vertical scrollbar */
    overflow: scroll; /* Horizontal and vertical scrollbar*/
}

Loading/Downloading image from URL on Swift

let url = NSURL.URLWithString("http://live-wallpaper.net/iphone/img/app/i/p/iphone-4s-wallpapers-mobile-backgrounds-dark_2466f886de3472ef1fa968033f1da3e1_raw_1087fae1932cec8837695934b7eb1250_raw.jpg");
var err: NSError?
var imageData :NSData = NSData.dataWithContentsOfURL(url,options: NSDataReadingOptions.DataReadingMappedIfSafe, error: &err)
var bgImage = UIImage(data:imageData)

What is a software framework?

I'm not sure there's a clear-cut definition of "framework". Sometimes a large set of libraries is called a framework, but I think the typical use of the word is closer to the definition aioobe brought.

This very nice article sums up the difference between just a set of libraries and a framework:

A framework can be defined as a set of libraries that say “Don’t call us, we’ll call you.”

How does a framework help you? Because instead of writing something from scratch, you basically just extend a given, working application. You get a lot of productivity this way - sometimes the resulting application can be far more elaborate than you could have done on your own in the same time frame - but you usually trade in a lot of flexibility.

How can I access iframe elements with Javascript?

Using jQuery you can use contents(). For example:

var inside = $('#one').contents();

How to 'restart' an android application programmatically

Checkout intent properties like no history , clear back stack etc ... Intent.setFlags

Intent mStartActivity = new Intent(HomeActivity.this, SplashScreen.class);
int mPendingIntentId = 123456;
PendingIntent mPendingIntent = PendingIntent.getActivity(HomeActivity.this, mPendingIntentId, mStartActivity,
PendingIntent.FLAG_CANCEL_CURRENT);
AlarmManager mgr = (AlarmManager) HomeActivity.this.getSystemService(Context.ALARM_SERVICE);
mgr.set(AlarmManager.RTC, System.currentTimeMillis() + 100, mPendingIntent);
System.exit(0);

psql: FATAL: database "<user>" does not exist

Had the same problem, a simple psql -d postgres did it (Type the command in the terminal)

How to install mod_ssl for Apache httpd?

I found I needed to enable the SSL module in Apache (obviously prefix commands with sudo if you are not running as root):

a2enmod ssl

then restart Apache:

/etc/init.d/apache2 restart

More details of SSL in Apache for Ubuntu / Debian here.

JQuery, Spring MVC @RequestBody and JSON - making it work together

In addition to the answers here...

if you are using jquery on the client side, this worked for me:

Java:

@RequestMapping(value = "/ajax/search/sync") 
public String sync(@RequestBody Foo json) {

Jquery (you need to include Douglas Crockford's json2.js to have the JSON.stringify function):

$.ajax({
    type: "post",
    url: "sync", //your valid url
    contentType: "application/json", //this is required for spring 3 - ajax to work (at least for me)
    data: JSON.stringify(jsonobject), //json object or array of json objects
    success: function(result) {
        //do nothing
    },
    error: function(){
        alert('failure');
    }
});

Django set default form values

I had this other solution (I'm posting it in case someone else as me is using the following method from the model):

class onlyUserIsActiveField(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(onlyUserIsActiveField, self).__init__(*args, **kwargs)
        self.fields['is_active'].initial = False

    class Meta:
        model = User
        fields = ['is_active']
        labels = {'is_active': 'Is Active'}
        widgets = {
            'is_active': forms.CheckboxInput( attrs={
                            'class':          'form-control bootstrap-switch',
                            'data-size':      'mini',
                            'data-on-color':  'success',
                            'data-on-text':   'Active',
                            'data-off-color': 'danger',
                            'data-off-text':  'Inactive',
                            'name':           'is_active',

            })
        }

The initial is definded on the __init__ function as self.fields['is_active'].initial = False

How to determine if one array contains all elements of another array

a = [5, 1, 6, 14, 2, 8]
b = [2, 6, 15]

a - b
# => [5, 1, 14, 8]

b - a
# => [15]

(b - a).empty?
# => false

How do I fix "Expected to return a value at the end of arrow function" warning?

The most upvoted answer, from Kris Selbekk, it is totally right. It is important to highlight though that it takes a functional approach, you will be looping through the this.props.comments array twice, the second time(looping) it will most probable skip a few elements that where filtered, but in case no comment was filtered you will loop through the whole array twice. If performance is not a concern in you project that is totally fine. In case performance is important a guard clause would be more appropriated as you would loop the array only once:

return this.props.comments.map((comment) => {
  if (!comment.hasComments) return null; 

  return (
    <div key={comment.id}>         
      <CommentItem className="MainComment"/>
        {this.props.comments.map(commentReply => {             
          if (commentReply.replyTo !== comment.id) return null;

          return <CommentItem className="SubComment"/>
        })} 
    </div>          
  ) 
}

The main reason I'm pointing this out is because as a Junior Developer I did a lot of those mistakes(like looping the same array multiple times), so I thought i was worth mention it here.

PS: I would refactor your react component even more, as I'm not in favour of heavy logic in the html part of a JSX, but that is out of the topic of this question.

Command for restarting all running docker containers?

Just run

docker restart $(docker ps -q)

Update

For Docker 1.13.1 use docker restart $(docker ps -a -q) as in answer lower.

Converting a string to JSON object

var Data=[{"id": "name2", "label": "Quantity"}]

Pass the string variable into Json parse :

Objdata= Json.parse(Data);

Best way to generate a random float in C#

Any reason not to use Random.NextDouble and then cast to float? That will give you a float between 0 and 1.

If you want a different form of "best" you'll need to specify your requirements. Note that Random shouldn't be used for sensitive matters such as finance or security - and you should generally reuse an existing instance throughout your application, or one per thread (as Random isn't thread-safe).

EDIT: As suggested in comments, to convert this to a range of float.MinValue, float.MaxValue:

// Perform arithmetic in double type to avoid overflowing
double range = (double) float.MaxValue - (double) float.MinValue;
double sample = rng.NextDouble();
double scaled = (sample * range) + float.MinValue;
float f = (float) scaled;

EDIT: Now you've mentioned that this is for unit testing, I'm not sure it's an ideal approach. You should probably test with concrete values instead - making sure you test with samples in each of the relevant categories - infinities, NaNs, denormal numbers, very large numbers, zero, etc.

Error "The goal you specified requires a project to execute but there is no POM in this directory" after executing maven command

  • The execution of maven command required pom.xml file that contains information about the project and configuration details used by Maven to build the project. It contains default values for most projects.

  • Make sure that porject should contains pom.xml at the root level.

Plot Normal distribution with Matplotlib

Note: This solution is using pylab, not matplotlib.pyplot

You may try using hist to put your data info along with the fitted curve as below:

import numpy as np
import scipy.stats as stats
import pylab as pl

h = sorted([186, 176, 158, 180, 186, 168, 168, 164, 178, 170, 189, 195, 172,
     187, 180, 186, 185, 168, 179, 178, 183, 179, 170, 175, 186, 159,
     161, 178, 175, 185, 175, 162, 173, 172, 177, 175, 172, 177, 180])  #sorted

fit = stats.norm.pdf(h, np.mean(h), np.std(h))  #this is a fitting indeed

pl.plot(h,fit,'-o')

pl.hist(h,normed=True)      #use this to draw histogram of your data

pl.show()                   #use may also need add this 

enter image description here

How to fix docker: Got permission denied issue

If you want to run docker as non-root user then you need to add it to the docker group.

  1. Create the docker group if it does not exist
$ sudo groupadd docker
  1. Add your user to the docker group.
$ sudo usermod -aG docker $USER
  1. Run the following command or Logout and login again and run (that doesn't work you may need to reboot your machine first)
$ newgrp docker

  1. Check if docker can be run without root
$ docker run hello-world

Reboot if still got error

$ reboot

Taken from the docker official documentation: manage-docker-as-a-non-root-user

How to create a new variable in a data.frame based on a condition?

One obvious and straightforward possibility is to use "if-else conditions". In that example

x <- c(1, 2, 4)
y <- c(1, 4, 5)
w <- ifelse(x <= 1, "good", ifelse((x >= 3) & (x <= 5), "bad", "fair"))
data.frame(x, y, w)

** For the additional question in the edit** Is that what you expect ?

> d1 <- c("e", "c", "a")
> d2 <- c("e", "a", "b")
> 
> w <- ifelse((d1 == "e") & (d2 == "e"), 1, 
+    ifelse((d1=="a") & (d2 == "b"), 2,
+    ifelse((d1 == "e"), 3, 99)))
>     
> data.frame(d1, d2, w)
  d1 d2  w
1  e  e  1
2  c  a 99
3  a  b  2

If you do not feel comfortable with the ifelse function, you can also work with the if and else statements for such applications.

How to print binary tree diagram?

I've made an improved algorithm for this, which handles nicely nodes with different size. It prints top-down using lines.

package alg;

import java.util.ArrayList;
import java.util.List;


/**
 * Binary tree printer
 * 
 * @author MightyPork
 */
public class TreePrinter
{
    /** Node that can be printed */
    public interface PrintableNode
    {
        /** Get left child */
        PrintableNode getLeft();


        /** Get right child */
        PrintableNode getRight();


        /** Get text to be printed */
        String getText();
    }


    /**
     * Print a tree
     * 
     * @param root
     *            tree root node
     */
    public static void print(PrintableNode root)
    {
        List<List<String>> lines = new ArrayList<List<String>>();

        List<PrintableNode> level = new ArrayList<PrintableNode>();
        List<PrintableNode> next = new ArrayList<PrintableNode>();

        level.add(root);
        int nn = 1;

        int widest = 0;

        while (nn != 0) {
            List<String> line = new ArrayList<String>();

            nn = 0;

            for (PrintableNode n : level) {
                if (n == null) {
                    line.add(null);

                    next.add(null);
                    next.add(null);
                } else {
                    String aa = n.getText();
                    line.add(aa);
                    if (aa.length() > widest) widest = aa.length();

                    next.add(n.getLeft());
                    next.add(n.getRight());

                    if (n.getLeft() != null) nn++;
                    if (n.getRight() != null) nn++;
                }
            }

            if (widest % 2 == 1) widest++;

            lines.add(line);

            List<PrintableNode> tmp = level;
            level = next;
            next = tmp;
            next.clear();
        }

        int perpiece = lines.get(lines.size() - 1).size() * (widest + 4);
        for (int i = 0; i < lines.size(); i++) {
            List<String> line = lines.get(i);
            int hpw = (int) Math.floor(perpiece / 2f) - 1;

            if (i > 0) {
                for (int j = 0; j < line.size(); j++) {

                    // split node
                    char c = ' ';
                    if (j % 2 == 1) {
                        if (line.get(j - 1) != null) {
                            c = (line.get(j) != null) ? '-' : '+';
                        } else {
                            if (j < line.size() && line.get(j) != null) c = '+';
                        }
                    }
                    System.out.print(c);

                    // lines and spaces
                    if (line.get(j) == null) {
                        for (int k = 0; k < perpiece - 1; k++) {
                            System.out.print(" ");
                        }
                    } else {

                        for (int k = 0; k < hpw; k++) {
                            System.out.print(j % 2 == 0 ? " " : "-");
                        }
                        System.out.print(j % 2 == 0 ? "+" : "+");
                        for (int k = 0; k < hpw; k++) {
                            System.out.print(j % 2 == 0 ? "-" : " ");
                        }
                    }
                }
                System.out.println();
            }

            // print line of numbers
            for (int j = 0; j < line.size(); j++) {

                String f = line.get(j);
                if (f == null) f = "";
                int gap1 = (int) Math.ceil(perpiece / 2f - f.length() / 2f);
                int gap2 = (int) Math.floor(perpiece / 2f - f.length() / 2f);

                // a number
                for (int k = 0; k < gap1; k++) {
                    System.out.print(" ");
                }
                System.out.print(f);
                for (int k = 0; k < gap2; k++) {
                    System.out.print(" ");
                }
            }
            System.out.println();

            perpiece /= 2;
        }
    }
}

To use this for your Tree, let your Node class implement PrintableNode.

Example output:

                                         2952:0                                             
                    +-----------------------------------------------+                       
                 1249:-1                                         5866:0                     
        +-----------------------+                       +-----------------------+           
     491:-1                  1572:0                  4786:1                  6190:0         
  +-----+                                               +-----+           +-----------+     
339:0                                                      5717:0      6061:0      6271:0   

Find a value anywhere in a database

This might help you. - from Narayana Vyas. It searches all columns of all tables in a given database. I have used it before and it works.

This is the Stored Proc from the above link - the only change I made was substituting the temp table for a table variable so you don't have to remember to drop it each time.

CREATE PROC SearchAllTables
(
    @SearchStr nvarchar(100)
)
AS
BEGIN

-- Copyright © 2002 Narayana Vyas Kondreddi. All rights reserved.
-- Purpose: To search all columns of all tables for a given search string
-- Written by: Narayana Vyas Kondreddi
-- Site: http://vyaskn.tripod.com
-- Tested on: SQL Server 7.0 and SQL Server 2000
-- Date modified: 28th July 2002 22:50 GMT

DECLARE @Results TABLE(ColumnName nvarchar(370), ColumnValue nvarchar(3630))

SET NOCOUNT ON

DECLARE @TableName nvarchar(256), @ColumnName nvarchar(128), @SearchStr2 nvarchar(110)
SET  @TableName = ''
SET @SearchStr2 = QUOTENAME('%' + @SearchStr + '%','''')

WHILE @TableName IS NOT NULL
BEGIN
    SET @ColumnName = ''
    SET @TableName = 
    (
        SELECT MIN(QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME))
        FROM    INFORMATION_SCHEMA.TABLES
        WHERE       TABLE_TYPE = 'BASE TABLE'
            AND QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME) > @TableName
            AND OBJECTPROPERTY(
                    OBJECT_ID(
                        QUOTENAME(TABLE_SCHEMA) + '.' + QUOTENAME(TABLE_NAME)
                         ), 'IsMSShipped'
                           ) = 0
    )

    WHILE (@TableName IS NOT NULL) AND (@ColumnName IS NOT NULL)
    BEGIN
        SET @ColumnName =
        (
            SELECT MIN(QUOTENAME(COLUMN_NAME))
            FROM    INFORMATION_SCHEMA.COLUMNS
            WHERE       TABLE_SCHEMA    = PARSENAME(@TableName, 2)
                AND TABLE_NAME  = PARSENAME(@TableName, 1)
                AND DATA_TYPE IN ('char', 'varchar', 'nchar', 'nvarchar')
                AND QUOTENAME(COLUMN_NAME) > @ColumnName
        )

        IF @ColumnName IS NOT NULL
        BEGIN
            INSERT INTO @Results
            EXEC
            (
                'SELECT ''' + @TableName + '.' + @ColumnName + ''', LEFT(' + @ColumnName + ', 3630) 
                FROM ' + @TableName + ' (NOLOCK) ' +
                ' WHERE ' + @ColumnName + ' LIKE ' + @SearchStr2
            )
        END
    END 
END

SELECT ColumnName, ColumnValue FROM @Results
END

Is using 'var' to declare variables optional?

Check out this Fiddle: http://jsfiddle.net/GWr6Z/2/

function doMe(){

a = "123"; // will be global
var b = "321"; // local to doMe
alert("a:"+a+"  --  b:"+b);

b = "something else"; // still local (not global)
alert("a:"+a+"  --  b:"+b);

};


doMe()
alert("a:"+a+"  --  b:"+b); // `b` will not be defined, check console.log

If input field is empty, disable submit button

For those that use coffeescript, I've put the code we use globally to disable the submit buttons on our most widely used form. An adaption of Adil's answer above.

$('#new_post button').prop 'disabled', true
$('#new_post #post_message').keyup ->
    $('#new_post button').prop 'disabled', if @value == '' then true else false
    return

How to check if a String contains another String in a case insensitive manner in Java?

String x="abCd";
System.out.println(Pattern.compile("c",Pattern.CASE_INSENSITIVE).matcher(x).find());

LINQ Orderby Descending Query

You need to choose a Property to sort by and pass it as a lambda expression to OrderByDescending

like:

.OrderByDescending(x => x.Delivery.SubmissionDate);

Really, though the first version of your LINQ statement should work. Is t.Delivery.SubmissionDate actually populated with valid dates?

Genymotion error at start 'Unable to load virtualbox'

Don't ask what this has to do with that , but by right clicking the genymotion application file and changing to compatibility to Vista solved the problem!

What does "yield break;" do in C#?

yield break is just a way of saying return for the last time and don't return any value

e.g

// returns 1,2,3,4,5
IEnumerable<int> CountToFive()
{
    yield return 1;
    yield return 2;
    yield return 3;
    yield return 4;
    yield return 5;
    yield break;
    yield return 6;
    yield return 7;
    yield return 8;
    yield return 9;
 }

if arguments is equal to this string, define a variable like this string

You can use either "=" or "==" operators for string comparison in bash. The important factor is the spacing within the brackets. The proper method is for brackets to contain spacing within, and operators to contain spacing around. In some instances different combinations work; however, the following is intended to be a universal example.

if [ "$1" == "something" ]; then     ## GOOD

if [ "$1" = "something" ]; then      ## GOOD

if [ "$1"="something" ]; then        ## BAD (operator spacing)

if ["$1" == "something"]; then       ## BAD (bracket spacing)

Also, note double brackets are handled slightly differently compared to single brackets ...

if [[ $a == z* ]]; then   # True if $a starts with a "z" (pattern matching).
if [[ $a == "z*" ]]; then # True if $a is equal to z* (literal matching).

if [ $a == z* ]; then     # File globbing and word splitting take place.
if [ "$a" == "z*" ]; then # True if $a is equal to z* (literal matching).

I hope that helps!

Dynamically load JS inside JS

jQuery's $.getScript() is buggy sometimes, so I use my own implementation of it like:

jQuery.loadScript = function (url, callback) {
    jQuery.ajax({
        url: url,
        dataType: 'script',
        success: callback,
        async: true
    });
}

and use it like:

if (typeof someObject == 'undefined') $.loadScript('url_to_someScript.js', function(){
    //Stuff to do after someScript has loaded
});

What does the DOCKER_HOST variable do?

Ok, I think I got it.

The client is the docker command installed into OS X.

The host is the Boot2Docker VM.

The daemon is a background service running inside Boot2Docker.

This variable tells the client how to connect to the daemon.

When starting Boot2Docker, the terminal window that pops up already has DOCKER_HOST set, so that's why docker commands work. However, to run Docker commands in other terminal windows, you need to set this variable in those windows.

Failing to set it gives a message like this:

$ docker run hello-world
2014/08/11 11:41:42 Post http:///var/run/docker.sock/v1.13/containers/create: 
dial unix /var/run/docker.sock: no such file or directory

One way to fix that would be to simply do this:

$ export DOCKER_HOST=tcp://192.168.59.103:2375

But, as pointed out by others, it's better to do this:

$ $(boot2docker shellinit)
$ docker run hello-world
Hello from Docker. [...]

To spell out this possibly non-intuitive Bash command, running boot2docker shellinit returns a set of Bash commands that set environment variables:

export DOCKER_HOST=tcp://192.168.59.103:2376
export DOCKER_CERT_PATH=/Users/ddavison/.boot2docker/certs/boot2docker-vm
export DOCKER_TLS_VERIFY=1

Hence running $(boot2docker shellinit) generates those commands, and then runs them.

How to scroll up or down the page to an anchor using jQuery?

following solution worked for me:

$("a[href^=#]").click(function(e)
        {
            e.preventDefault();
            var aid = $(this).attr('href');
            console.log(aid);
            aid = aid.replace("#", "");
            var aTag = $("a[name='"+ aid +"']");
            if(aTag == null || aTag.offset() == null)
                aTag = $("a[id='"+ aid +"']");

            $('html,body').animate({scrollTop: aTag.offset().top}, 1000);
        }
    );

How can I check if a Perl array contains a particular value?

@files is an existing array

my @new_values =  grep(/^2[\d].[\d][A-za-z]?/,@files);

print join("\n", @new_values);

print "\n";

/^2[\d].[\d][A-za-z]?/ = vaues starting from 2 here you can put any regular expression

Special characters like @ and & in cURL POST data

I did this

~]$ export A=g

~]$ export B=!

~]$ export C=nger


   curl http://<>USERNAME<>1:$A$B$C@<>URL<>/<>PATH<>/

MySQL: Selecting multiple fields into multiple variables in a stored procedure

Alternatively to Martin's answer, you could also add the INTO part at the end of the query to make the query more readable:

SELECT Id, dateCreated FROM products INTO iId, dCreate

How to know if other threads have finished?

There are a number of ways you can do this:

  1. Use Thread.join() in your main thread to wait in a blocking fashion for each Thread to complete, or
  2. Check Thread.isAlive() in a polling fashion -- generally discouraged -- to wait until each Thread has completed, or
  3. Unorthodox, for each Thread in question, call setUncaughtExceptionHandler to call a method in your object, and program each Thread to throw an uncaught Exception when it completes, or
  4. Use locks or synchronizers or mechanisms from java.util.concurrent, or
  5. More orthodox, create a listener in your main Thread, and then program each of your Threads to tell the listener that they have completed.

How to implement Idea #5? Well, one way is to first create an interface:

public interface ThreadCompleteListener {
    void notifyOfThreadComplete(final Thread thread);
}

then create the following class:

public abstract class NotifyingThread extends Thread {
  private final Set<ThreadCompleteListener> listeners
                   = new CopyOnWriteArraySet<ThreadCompleteListener>();
  public final void addListener(final ThreadCompleteListener listener) {
    listeners.add(listener);
  }
  public final void removeListener(final ThreadCompleteListener listener) {
    listeners.remove(listener);
  }
  private final void notifyListeners() {
    for (ThreadCompleteListener listener : listeners) {
      listener.notifyOfThreadComplete(this);
    }
  }
  @Override
  public final void run() {
    try {
      doRun();
    } finally {
      notifyListeners();
    }
  }
  public abstract void doRun();
}

and then each of your Threads will extend NotifyingThread and instead of implementing run() it will implement doRun(). Thus when they complete, they will automatically notify anyone waiting for notification.

Finally, in your main class -- the one that starts all the Threads (or at least the object waiting for notification) -- modify that class to implement ThreadCompleteListener and immediately after creating each Thread add itself to the list of listeners:

NotifyingThread thread1 = new OneOfYourThreads();
thread1.addListener(this); // add ourselves as a listener
thread1.start();           // Start the Thread

then, as each Thread exits, your notifyOfThreadComplete method will be invoked with the Thread instance that just completed (or crashed).

Note that better would be to implements Runnable rather than extends Thread for NotifyingThread as extending Thread is usually discouraged in new code. But I'm coding to your question. If you change the NotifyingThread class to implement Runnable then you have to change some of your code that manages Threads, which is pretty straightforward to do.

Convert DataTable to List<T>

There are Linq extension methods for DataTable.

Add reference to: System.Data.DataSetExtensions.dll

Then include the namespace: using System.Data.DataSetExtensions

Finally you can use Linq extensions on DataSet and DataTables:

var matches = myDataSet.Tables.First().Where(dr=>dr.Field<int>("id") == 1);

On .Net 2.0 you can still add generic method:

public static List<T> ConvertRowsToList<T>( DataTable input, Convert<DataRow, T> conversion) {
    List<T> retval = new List<T>()
    foreach(DataRow dr in input.Rows)
        retval.Add( conversion(dr) );

    return retval;
}

Static method in a generic class?

It is correctly mentioned in the error: you cannot make a static reference to non-static type T. The reason is the type parameter T can be replaced by any of the type argument e.g. Clazz<String> or Clazz<integer> etc. But static fields/methods are shared by all non-static objects of the class.

The following excerpt is taken from the doc:

A class's static field is a class-level variable shared by all non-static objects of the class. Hence, static fields of type parameters are not allowed. Consider the following class:

public class MobileDevice<T> {
    private static T os;

    // ...
}

If static fields of type parameters were allowed, then the following code would be confused:

MobileDevice<Smartphone> phone = new MobileDevice<>();
MobileDevice<Pager> pager = new MobileDevice<>();
MobileDevice<TabletPC> pc = new MobileDevice<>();

Because the static field os is shared by phone, pager, and pc, what is the actual type of os? It cannot be Smartphone, Pager, and TabletPC at the same time. You cannot, therefore, create static fields of type parameters.

As rightly pointed out by chris in his answer you need to use type parameter with the method and not with the class in this case. You can write it like:

static <E> void doIt(E object) 

Generating PDF files with JavaScript

I've just written a library called jsPDF which generates PDFs using Javascript alone. It's still very young, and I'll be adding features and bug fixes soon. Also got a few ideas for workarounds in browsers that do not support Data URIs. It's licensed under a liberal MIT license.

I came across this question before I started writing it and thought I'd come back and let you know :)

Generate PDFs in Javascript

Example create a "Hello World" PDF file.

_x000D_
_x000D_
// Default export is a4 paper, portrait, using milimeters for units_x000D_
var doc = new jsPDF()_x000D_
_x000D_
doc.text('Hello world!', 10, 10)_x000D_
doc.save('a4.pdf')
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jspdf/1.3.5/jspdf.debug.js"></script>
_x000D_
_x000D_
_x000D_

How to display string that contains HTML in twig template?

You can also use:

{{ word|striptags('<b>')|raw }}

so that only <b> tag will be allowed.

Comparing two files in linux terminal

Sort them and use comm:

comm -23 <(sort a.txt) <(sort b.txt)

comm compares (sorted) input files and by default outputs three columns: lines that are unique to a, lines that are unique to b, and lines that are present in both. By specifying -1, -2 and/or -3 you can suppress the corresponding output. Therefore comm -23 a b lists only the entries that are unique to a. I use the <(...) syntax to sort the files on the fly, if they are already sorted you don't need this.

How to "add existing frameworks" in Xcode 4?

  1. In the project navigator, select your project.

  2. Select your target.

  3. Select the "Build Phases" tab.

  4. expander. Click the + button.

  5. Select your framework.

  6. (optional) Drag and drop the added framework to the "Frameworks" group.

    enter image description here

How to work offline with TFS

There are couple of little visual studio extensions for this purpose:

  1. For VS2010 & TFS 2010, try this
  2. For VS2012 & TFS 2010, use this

In case of TFS 2012, looks like there is no need for 'Go offline' extensions. I read something about a new feature called local workspace for the similar purpose.

Alternatively I had good success with Git-TF. All the goodness of git and when you are ready, you can push it to TFS.

Displaying Total in Footer of GridView and also Add Sum of columns(row vise) in last Column

int total = 0;
protected void gvEmp_RowDataBound(object sender, GridViewRowEventArgs e)
{
if(e.Row.RowType==DataControlRowType.DataRow)
{
total += Convert.ToInt32(DataBinder.Eval(e.Row.DataItem, "Amount"));
}
if(e.Row.RowType==DataControlRowType.Footer)
{
Label lblamount = (Label)e.Row.FindControl("lblTotal");
lblamount.Text = total.ToString();
}
}

Sorting Characters Of A C++ String

There is a sorting algorithm in the standard library, in the header <algorithm>. It sorts inplace, so if you do the following, your original word will become sorted.

std::sort(word.begin(), word.end());

If you don't want to lose the original, make a copy first.

std::string sortedWord = word;
std::sort(sortedWord.begin(), sortedWord.end());

How do I find out where login scripts live?

The default location for logon scripts is the netlogon share of a domain controller. On the server this is located:

%SystemRoot%'SYSVOL'sysvol''scripts

It can presumably be changes from this default but I've never met anyone that had a reason to.

To get list of domain controllers programatically see this article: http://www.microsoft.com/technet/scriptcenter/resources/qanda/dec04/hey1216.mspx

jQuery find element by data attribute value

I searched for a the same solution with a variable instead of the String.
I hope i can help someone with my solution :)

var numb = "3";
$(`#myid[data-tab-id=${numb}]`);

Use FontAwesome or Glyphicons with css :before

This approach should be avoided. The default value for vertical-align is baseline. Changing the font-family of only the pseudo element will result in elements with differing fonts. Different fonts can have different font metrics and different baselines. In order for different baselines to align, the overall height of the element would have to increase. See this effect in action.

It is always better to have one element per font icon.

Docker can't connect to docker daemon

The Docker Service may not be running.

If you are on a RedHat/Fedora/CentOS, please try this:

sudo systemctl start docker

If you are on Ubuntu/Debian:

sudo service start docker

Docker will start running on your host and respective port.

nginx - nginx: [emerg] bind() to [::]:80 failed (98: Address already in use)

[::]:80 is a ipv6 address.

This error can be caused if you have a nginx configuration that is listening on port 80 and also on port [::]:80.

I had the following in my default sites-available file:

listen 80;
listen [::]:80 default_server;

You can fix this by adding ipv6only=on to the [::]:80 like this:

listen 80;
listen [::]:80 ipv6only=on default_server;

For more information, see:

http://forum.linode.com/viewtopic.php?t=8580

http://wiki.nginx.org/HttpCoreModule#listen

oracle diff: how to compare two tables?

Try This,

alter session set "_convert_set_to_join"= true;

The other alternative is to rewrite the SQL query manually [replacing the minus operator with a NOT IN subquery] evidences about 30% improvement in execution time .

 select * 
   from A 
    where (col1,col2,?) not in 
   (select col1,col2,? from B) 
   union all 
   select * from B 
  where (col1,col2,?) not in 
  (select col1,col2,? from A); 

I have referred from this post click here

How can I store HashMap<String, ArrayList<String>> inside a list?

First you need to define the List as :

List<Map<String, ArrayList<String>>> list = new ArrayList<>();

To add the Map to the List , use add(E e) method :

list.add(map);

How to create a file in Linux from terminal window?

Depending on what you want the file to contain:

  • touch /path/to/file for an empty file
  • somecommand > /path/to/file for a file containing the output of some command.

      eg: grep --help > randomtext.txt
          echo "This is some text" > randomtext.txt
    
  • nano /path/to/file or vi /path/to/file (or any other editor emacs,gedit etc)
    It either opens the existing one for editing or creates & opens the empty file to enter, if it doesn't exist


Create the file using cat

$ cat > myfile.txt

Now, just type whatever you want in the file:

Hello World!

CTRL-D to save and exit


There are several possible solutions:

Create an empty file

touch file

>file

echo -n > file

printf '' > file

The echo version will work only if your version of echo supports the -n switch to suppress newlines. This is a non-standard addition. The other examples will all work in a POSIX shell.

Create a file containing a newline and nothing else

echo '' > file

printf '\n' > file

This is a valid "text file" because it ends in a newline.

Write text into a file

"$EDITOR" file

echo 'text' > file

cat > file <<END \
text
END

printf 'text\n' > file

These are equivalent. The $EDITOR command assumes that you have an interactive text editor defined in the EDITOR environment variable and that you interactively enter equivalent text. The cat version presumes a literal newline after the \ and after each other line. Other than that these will all work in a POSIX shell.

Of course there are many other methods of writing and creating files, too.

jQuery and AJAX response header

The underlying XMLHttpRequest object used by jQuery will always silently follow redirects rather than return a 302 status code. Therefore, you can't use jQuery's AJAX request functionality to get the returned URL. Instead, you need to put all the data into a form and submit the form with the target attribute set to the value of the name attribute of the iframe:

$('#myIframe').attr('name', 'myIframe');

var form = $('<form method="POST" action="url.do"></form>').attr('target', 'myIframe');
$('<input type="hidden" />').attr({name: 'search', value: 'test'}).appendTo(form);

form.appendTo(document.body);
form.submit();

The server's url.do page will be loaded in the iframe, but when its 302 status arrives, the iframe will be redirected to the final destination.

Bootstrap 3 : Vertically Center Navigation Links when Logo Increasing The Height of Navbar

Bootstrap sets the height of the navbar automatically to 50px. The padding above and below links is set to 15px. I think that bootstrap is adding padding to your logo.

You can either remove some of the padding above and below your logo or you can add more padding above and below links.

Adding more padding should look something like this:

nav.navbar-inverse>li>a {
 padding-top: 25px;
 padding-bottom: 25px;
}

Determine what user created objects in SQL Server

If each user has its own SQL Server login you could try this

select 
    so.name, su.name, so.crdate 
from 
    sysobjects so 
join 
    sysusers su on so.uid = su.uid  
order by 
    so.crdate

How to close a Java Swing application from the code

Try:

System.exit(0);

Crude, but effective.

Do while loop in SQL Server 2008

I am not sure about DO-WHILE IN MS SQL Server 2008 but you can change your WHILE loop logic, so as to USE like DO-WHILE loop.

Examples are taken from here: http://blog.sqlauthority.com/2007/10/24/sql-server-simple-example-of-while-loop-with-continue-and-break-keywords/

  1. Example of WHILE Loop

    DECLARE @intFlag INT
    SET @intFlag = 1
    WHILE (@intFlag <=5)
    BEGIN
        PRINT @intFlag
        SET @intFlag = @intFlag + 1
    END
    GO
    

    ResultSet:

    1
    2
    3
    4
    5
    
  2. Example of WHILE Loop with BREAK keyword

    DECLARE @intFlag INT
    SET @intFlag = 1
    WHILE (@intFlag <=5)
    BEGIN
        PRINT @intFlag
        SET @intFlag = @intFlag + 1
        IF @intFlag = 4
            BREAK;
    END
    GO
    

    ResultSet:

    1
    2
    3
    
  3. Example of WHILE Loop with CONTINUE and BREAK keywords

    DECLARE @intFlag INT
    SET @intFlag = 1
    WHILE (@intFlag <=5)
    BEGIN
        PRINT @intFlag
        SET @intFlag = @intFlag + 1
        CONTINUE;
        IF @intFlag = 4 -- This will never executed
            BREAK;
    END
    GO
    

    ResultSet:

    1
    2
    3
    4
    5
    

But try to avoid loops at database level. Reference.

React Hook Warnings for async function in useEffect: useEffect function must return a cleanup function or nothing

I suggest to look at Dan Abramov (one of the React core maintainers) answer here:

I think you're making it more complicated than it needs to be.

function Example() {
  const [data, dataSet] = useState<any>(null)

  useEffect(() => {
    async function fetchMyAPI() {
      let response = await fetch('api/data')
      response = await response.json()
      dataSet(response)
    }

    fetchMyAPI()
  }, [])

  return <div>{JSON.stringify(data)}</div>
}

Longer term we'll discourage this pattern because it encourages race conditions. Such as — anything could happen between your call starts and ends, and you could have gotten new props. Instead, we'll recommend Suspense for data fetching which will look more like

const response = MyAPIResource.read();

and no effects. But in the meantime you can move the async stuff to a separate function and call it.

You can read more about experimental suspense here.


If you want to use functions outside with eslint.

 function OutsideUsageExample() {
  const [data, dataSet] = useState<any>(null)

  const fetchMyAPI = useCallback(async () => {
    let response = await fetch('api/data')
    response = await response.json()
    dataSet(response)
  }, [])

  useEffect(() => {
    fetchMyAPI()
  }, [fetchMyAPI])

  return (
    <div>
      <div>data: {JSON.stringify(data)}</div>
      <div>
        <button onClick={fetchMyAPI}>manual fetch</button>
      </div>
    </div>
  )
}

If you will use useCallback, look at example of how it works useCallback. Sandbox.

import React, { useState, useEffect, useCallback } from "react";

export default function App() {
  const [counter, setCounter] = useState(1);

  // if counter is changed, than fn will be updated with new counter value
  const fn = useCallback(() => {
    setCounter(counter + 1);
  }, [counter]);

  // if counter is changed, than fn will not be updated and counter will be always 1 inside fn
  /*const fnBad = useCallback(() => {
      setCounter(counter + 1);
    }, []);*/

  // if fn or counter is changed, than useEffect will rerun
  useEffect(() => {
    if (!(counter % 2)) return; // this will stop the loop if counter is not even

    fn();
  }, [fn, counter]);

  // this will be infinite loop because fn is always changing with new counter value
  /*useEffect(() => {
    fn();
  }, [fn]);*/

  return (
    <div>
      <div>Counter is {counter}</div>
      <button onClick={fn}>add +1 count</button>
    </div>
  );
}

Try catch statements in C

A quick google search yields kludgey solutions such as this that use setjmp/longjmp as others have mentioned. Nothing as straightforward and elegant as C++/Java's try/catch. I'm rather partial to Ada's exception handling myself.

Check everything with if statements :)

How can I add an item to a ListBox in C# and WinForms?

list.Items.add(new ListBoxItem("name", "value"));

The internal (default) data structure of the ListBox is the ListBoxItem.

How do I iterate over an NSArray?

Add each method in your NSArray category, you gonna need it a lot

Code taken from ObjectiveSugar

- (void)each:(void (^)(id object))block {
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
        block(obj);
    }];
}

Getting one value from a tuple

You can write

i = 5 + tup()[0]

Tuples can be indexed just like lists.

The main difference between tuples and lists is that tuples are immutable - you can't set the elements of a tuple to different values, or add or remove elements like you can from a list. But other than that, in most situations, they work pretty much the same.

What charset does Microsoft Excel use when saving files?

I had a similar problem last week. I received a number of CSV files with varying encodings. Before importing into the database I then used the chardet libary to automatically sniff out the correct encoding.

Chardet is a port from Mozillas character detection engine and if the sample size is large enough (one accentuated character will not do) works really well.

C# Numeric Only TextBox Control

this way is right with me:

private void textboxNumberic_KeyPress(object sender, KeyPressEventArgs e)
{
     const char Delete = (char)8;
     e.Handled = !Char.IsDigit(e.KeyChar) && e.KeyChar != Delete;
}

Input and output numpy arrays to h5py

A cleaner way to handle file open/close and avoid memory leaks:

Prep:

import numpy as np
import h5py

data_to_write = np.random.random(size=(100,20)) # or some such

Write:

with h5py.File('name-of-file.h5', 'w') as hf:
    hf.create_dataset("name-of-dataset",  data=data_to_write)

Read:

with h5py.File('name-of-file.h5', 'r') as hf:
    data = hf['name-of-dataset'][:]

Replace transparency in PNG images with white background

-background white -alpha remove -alpha off

Example:

convert image.png -background white -alpha remove -alpha off white.png

Feel free to replace white with any other color you want. Imagemagick documentation says this about the -alpha remove operation:

This operation is simple and fast, and does the job without needing any extra memory use, or other side effects that may be associated with alternative transparency removal techniques. It is thus the preferred way of removing image transparency.

How can you test if an object has a specific property?

I ended up with the following function ...

function HasNoteProperty(
    [object]$testObject,
    [string]$propertyName
)
{
    $members = Get-Member -InputObject $testObject 
    if ($members -ne $null -and $members.count -gt 0) 
    { 
        foreach($member in $members) 
        { 
            if ( ($member.MemberType -eq "NoteProperty" )  -and `
                 ($member.Name       -eq $propertyName) ) 
            { 
                return $true 
            } 
        } 
        return $false 
    } 
    else 
    { 
        return $false; 
    }
}

python: creating list from string

Try this:

b = [ entry.split(',') for entry in a ]
b = [ b[i] if i % 3 == 0 else int(b[i]) for i in xrange(0, len(b)) ]

MySQL combine two columns and add into a new column

Add new column to your table and perfrom the query:

UPDATE tbl SET combined = CONCAT(zipcode, ' - ', city, ', ', state)

how to draw smooth curve through N points using javascript HTML5 canvas?

To add to K3N's cardinal splines method and perhaps address T. J. Crowder's concerns about curves 'dipping' in misleading places, I inserted the following code in the getCurvePoints() function, just before res.push(x);

if ((y < _pts[i+1] && y < _pts[i+3]) || (y > _pts[i+1] && y > _pts[i+3])) {
    y = (_pts[i+1] + _pts[i+3]) / 2;
}
if ((x < _pts[i] && x < _pts[i+2]) || (x > _pts[i] && x > _pts[i+2])) {
    x = (_pts[i] + _pts[i+2]) / 2;
}

This effectively creates a (invisible) bounding box between each pair of successive points and ensures the curve stays within this bounding box - ie. if a point on the curve is above/below/left/right of both points, it alters its position to be within the box. Here the midpoint is used, but this could be improved upon, perhaps using linear interpolation.

What does <meta http-equiv="X-UA-Compatible" content="IE=edge"> do?

Use this to force IE to hide that annoying browser compatibility button in the address bar:

<meta http-equiv="X-UA-Compatible" content="IE=edge" />

Play audio as microphone input

Just as there are printer drivers that do not connect to a printer at all but rather write to a PDF file, analogously there are virtual audio drivers available that do not connect to a physical microphone at all but can pipe input from other sources such as files or other programs.

I hope I'm not breaking any rules by recommending free/donation software, but VB-Audio Virtual Cable should let you create a pair of virtual input and output audio devices. Then you could play an MP3 into the virtual output device and then set the virtual input device as your "microphone". In theory I think that should work.

If all else fails, you could always roll your own virtual audio driver. Microsoft provides some sample code but unfortunately it is not applicable to the older Windows XP audio model. There is probably sample code available for XP too.

How to deal with bad_alloc in C++?

You can catch it like any other exception:

try {
  foo();
}
catch (const std::bad_alloc&) {
  return -1;
}

Quite what you can usefully do from this point is up to you, but it's definitely feasible technically.



In general you cannot, and should not try, to respond to this error. bad_alloc indicates that a resource cannot be allocated because not enough memory is available. In most scenarios your program cannot hope to cope with that, and terminating soon is the only meaningful behaviour.

Worse, modern operating systems often over-allocate: on such systems, malloc and new can return a valid pointer even if there is not enough free memory left – std::bad_alloc will never be thrown, or is at least not a reliable sign of memory exhaustion. Instead, attempts to access the allocated memory will then result in a segmentation fault, which is not catchable (you can handle the segmentation fault signal, but you cannot resume the program afterwards).

The only thing you could do when catching std::bad_alloc is to perhaps log the error, and try to ensure a safe program termination by freeing outstanding resources (but this is done automatically in the normal course of stack unwinding after the error gets thrown if the program uses RAII appropriately).

In certain cases, the program may attempt to free some memory and try again, or use secondary memory (= disk) instead of RAM but these opportunities only exist in very specific scenarios with strict conditions:

  1. The application must ensure that it runs on a system that does not overcommit memory, i.e. it signals failure upon allocation rather than later.
  2. The application must be able to free memory immediately, without any further accidental allocations in the meantime.

It’s exceedingly rare that applications have control over point 1 — userspace applications never do, it’s a system-wide setting that requires root permissions to change.1

OK, so let’s assume you’ve fixed point 1. What you can now do is for instance use a LRU cache for some of your data (probably some particularly large business objects that can be regenerated or reloaded on demand). Next, you need to put the actual logic that may fail into a function that supports retry — in other words, if it gets aborted, you can just relaunch it:

lru_cache<widget> widget_cache;

double perform_operation(int widget_id) {
    std::optional<widget> maybe_widget = widget_cache.find_by_id(widget_id);
    if (not maybe_widget) {
        maybe_widget = widget_cache.store(widget_id, load_widget_from_disk(widget_id));
    }
    return maybe_widget->frobnicate();
}

…

for (int num_attempts = 0; num_attempts < MAX_NUM_ATTEMPTS; ++num_attempts) {
    try {
        return perform_operation(widget_id);
    } catch (std::bad_alloc const&) {
        if (widget_cache.empty()) throw; // memory error elsewhere.
        widget_cache.remove_oldest();
    }
}

// Handle too many failed attempts here.

But even here, using std::set_new_handler instead of handling std::bad_alloc provides the same benefit and would be much simpler.


1 If you’re creating an application that does control point 1, and you’re reading this answer, please shoot me an email, I’m genuinely curious about your circumstances.


What is the C++ Standard specified behavior of new in c++?

The usual notion is that if new operator cannot allocate dynamic memory of the requested size, then it should throw an exception of type std::bad_alloc.
However, something more happens even before a bad_alloc exception is thrown:

C++03 Section 3.7.4.1.3: says

An allocation function that fails to allocate storage can invoke the currently installed new_handler(18.4.2.2), if any. [Note: A program-supplied allocation function can obtain the address of the currently installed new_handler using the set_new_handler function (18.4.2.3).] If an allocation function declared with an empty exception-specification (15.4), throw(), fails to allocate storage, it shall return a null pointer. Any other allocation function that fails to allocate storage shall only indicate failure by throw-ing an exception of class std::bad_alloc (18.4.2.1) or a class derived from std::bad_alloc.

Consider the following code sample:

#include <iostream>
#include <cstdlib>

// function to call if operator new can't allocate enough memory or error arises
void outOfMemHandler()
{
    std::cerr << "Unable to satisfy request for memory\n";

    std::abort();
}

int main()
{
    //set the new_handler
    std::set_new_handler(outOfMemHandler);

    //Request huge memory size, that will cause ::operator new to fail
    int *pBigDataArray = new int[100000000L];

    return 0;
}

In the above example, operator new (most likely) will be unable to allocate space for 100,000,000 integers, and the function outOfMemHandler() will be called, and the program will abort after issuing an error message.

As seen here the default behavior of new operator when unable to fulfill a memory request, is to call the new-handler function repeatedly until it can find enough memory or there is no more new handlers. In the above example, unless we call std::abort(), outOfMemHandler() would be called repeatedly. Therefore, the handler should either ensure that the next allocation succeeds, or register another handler, or register no handler, or not return (i.e. terminate the program). If there is no new handler and the allocation fails, the operator will throw an exception.

What is the new_handler and set_new_handler?

new_handler is a typedef for a pointer to a function that takes and returns nothing, and set_new_handler is a function that takes and returns a new_handler.

Something like:

typedef void (*new_handler)();
new_handler set_new_handler(new_handler p) throw();

set_new_handler's parameter is a pointer to the function operator new should call if it can't allocate the requested memory. Its return value is a pointer to the previously registered handler function, or null if there was no previous handler.

How to handle out of memory conditions in C++?

Given the behavior of newa well designed user program should handle out of memory conditions by providing a proper new_handlerwhich does one of the following:

Make more memory available: This may allow the next memory allocation attempt inside operator new's loop to succeed. One way to implement this is to allocate a large block of memory at program start-up, then release it for use in the program the first time the new-handler is invoked.

Install a different new-handler: If the current new-handler can't make any more memory available, and of there is another new-handler that can, then the current new-handler can install the other new-handler in its place (by calling set_new_handler). The next time operator new calls the new-handler function, it will get the one most recently installed.

(A variation on this theme is for a new-handler to modify its own behavior, so the next time it's invoked, it does something different. One way to achieve this is to have the new-handler modify static, namespace-specific, or global data that affects the new-handler's behavior.)

Uninstall the new-handler: This is done by passing a null pointer to set_new_handler. With no new-handler installed, operator new will throw an exception ((convertible to) std::bad_alloc) when memory allocation is unsuccessful.

Throw an exception convertible to std::bad_alloc. Such exceptions are not be caught by operator new, but will propagate to the site originating the request for memory.

Not return: By calling abort or exit.

How do I decrease the size of my sql server log file?

This is one of the best suggestion in which is done using query. Good for those who has a lot of databases just like me. Can run it using a script.

https://medium.com/@bharatdwarkani/shrinking-sql-server-db-log-file-size-sql-server-db-maintenance-7ddb0c331668

USE DatabaseName;
GO
-- Truncate the log by changing the database recovery model to SIMPLE.
ALTER DATABASE DatabaseName
SET RECOVERY SIMPLE;
GO
-- Shrink the truncated log file to 1 MB.
DBCC SHRINKFILE (DatabaseName_Log, 1);
GO
-- Reset the database recovery model.
ALTER DATABASE DatabaseName
SET RECOVERY FULL;
GO

Converting user input string to regular expression

I suggest you also add separate checkboxes or a textfield for the special flags. That way it is clear that the user does not need to add any //'s. In the case of a replace, provide two textfields. This will make your life a lot easier.

Why? Because otherwise some users will add //'s while other will not. And some will make a syntax error. Then, after you stripped the //'s, you may end up with a syntactically valid regex that is nothing like what the user intended, leading to strange behaviour (from the user's perspective).

How do I plot only a table in Matplotlib?

Not sure if this is already answered, but if you want only a table in a figure window, then you can hide the axes:

fig, ax = plt.subplots()

# Hide axes
ax.xaxis.set_visible(False) 
ax.yaxis.set_visible(False)

# Table from Ed Smith answer
clust_data = np.random.random((10,3))
collabel=("col 1", "col 2", "col 3")
ax.table(cellText=clust_data,colLabels=collabel,loc='center')

Disable a Maven plugin defined in a parent POM

See if the plugin has a 'skip' configuration parameter. Nearly all do. if it does, just add it to a declaration in the child:

<plugin>
   <groupId>group</groupId>
   <artifactId>artifact</artifactId>
   <configuration>
     <skip>true</skip>
   </configuration>
</plugin>

If not, then use:

<plugin>    
<groupId>group</groupId>   
 <artifactId>artifact</artifactId>    
<executions>
     <execution>
       <id>TheNameOfTheRelevantExecution</id>
       <phase>none</phase>
     </execution>    
</executions>  
</plugin>

How do I format date and time on ssrs report?

First go to your control panel , select Date , time and Number Format . Now select English(United Kingdom) from the drop down list.

Make sure the shor date field is equal to 'dd/mm/yyyy'. Press Apply. Now go to SSRS and right click on the report in the empty space and select properties.

If you are using visual studio then set Language property equal to =User!Language.

If you are using Report Builder then Language property will appear in Localization section.

HTML Button Close Window

JavaScript can only close a window that was opened using JavaScript. Example below:

<script>
function myFunction() {
  var str = "Sample";
  var result = str.link("https://sample.com");
  document.getElementById("demo").innerHTML = result;
}
</script>

Center button under form in bootstrap

You can use this

<button type="submit" class="btn btn-primary btn-block w-50 mx-auto">Search</button>

Look something like this enter image description here

Complete Form code -

<form id="submit">
    <input type="text" class="form-control mt-5" id="search-city" 
           placeholder="Search City">
    <button type="submit" class="btn btn-primary mt-3 btn-sm btn-block w-50 
            mx-auto">Search</button>
   </form>

Modify SVG fill color when being served as Background-Image

You can store the SVG in a variable. Then manipulate the SVG string depending on your needs (i.e., set width, height, color, etc). Then use the result to set the background, e.g.

$circle-icon-svg: '<svg xmlns="http://www.w3.org/2000/svg"><circle cx="10" cy="10" r="10" /></svg>';

$icon-color: #f00;
$icon-color-hover: #00f;

@function str-replace($string, $search, $replace: '') {
    $index: str-index($string, $search);

    @if $index {
        @return str-slice($string, 1, $index - 1) + $replace + str-replace(str-slice($string, $index + str-length($search)), $search, $replace);
    }

    @return $string;
}

@function svg-fill ($svg, $color) {
  @return str-replace($svg, '<svg', '<svg fill="#{$color}"');
}

@function svg-size ($svg, $width, $height) {
  $svg: str-replace($svg, '<svg', '<svg width="#{$width}"');
  $svg: str-replace($svg, '<svg', '<svg height="#{$height}"');

  @return $svg;
}

.icon {
  $icon-svg: svg-size($circle-icon-svg, 20, 20);

  width: 20px; height: 20px; background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color)}');

  &:hover {
    background: url('data:image/svg+xml;utf8,#{svg-fill($icon-svg, $icon-color-hover)}');
  }
}

I have made a demo too, http://sassmeister.com/gist/4cf0265c5d0143a9e734.

This code makes a few assumptions about the SVG, e.g. that <svg /> element does not have an existing fill colour and that neither width or height properties are set. Since the input is hardcoded in the SCSS document, it is quite easy to enforce these constraints.

Do not worry about the code duplication. compression makes the difference negligible.

Removing the first 3 characters from a string

Use the substring method of the String class :

String removeCurrency=amount.getText().toString().substring(3);

(.text+0x20): undefined reference to `main' and undefined reference to function

This error means that, while linking, compiler is not able to find the definition of main() function anywhere.

In your makefile, the main rule will expand to something like this.

main: producer.o consumer.o AddRemove.o
   gcc -pthread -Wall -o producer.o consumer.o AddRemove.o

As per the gcc manual page, the use of -o switch is as below

-o file     Place output in file file. This applies regardless to whatever sort of output is being produced, whether it be an executable file, an object file, an assembler file or preprocessed C code. If -o is not specified, the default is to put an executable file in a.out.

It means, gcc will put the output in the filename provided immediate next to -o switch. So, here instead of linking all the .o files together and creating the binary [main, in your case], its creating the binary as producer.o, linking the other .o files. Please correct that.

How to view hierarchical package structure in Eclipse package explorer

Package Explorer / View Menu / Package Presentation... / Hierarchical

The "View Menu" can be opened with Ctrl + F10, or the small arrow-down icon in the top-right corner of the Package Explorer.

What are the advantages of NumPy over regular Python lists?

Alex mentioned memory efficiency, and Roberto mentions convenience, and these are both good points. For a few more ideas, I'll mention speed and functionality.

Functionality: You get a lot built in with NumPy, FFTs, convolutions, fast searching, basic statistics, linear algebra, histograms, etc. And really, who can live without FFTs?

Speed: Here's a test on doing a sum over a list and a NumPy array, showing that the sum on the NumPy array is 10x faster (in this test -- mileage may vary).

from numpy import arange
from timeit import Timer

Nelements = 10000
Ntimeits = 10000

x = arange(Nelements)
y = range(Nelements)

t_numpy = Timer("x.sum()", "from __main__ import x")
t_list = Timer("sum(y)", "from __main__ import y")
print("numpy: %.3e" % (t_numpy.timeit(Ntimeits)/Ntimeits,))
print("list:  %.3e" % (t_list.timeit(Ntimeits)/Ntimeits,))

which on my systems (while I'm running a backup) gives:

numpy: 3.004e-05
list:  5.363e-04

How can I make an "are you sure" prompt in a Windows batchfile?

You want something like:

@echo off
setlocal
:PROMPT
SET /P AREYOUSURE=Are you sure (Y/[N])?
IF /I "%AREYOUSURE%" NEQ "Y" GOTO END

echo ... rest of file ...


:END
endlocal

How to get all child inputs of a div element (jQuery)

here is my approach:

You can use it in other event.

_x000D_
_x000D_
var id;_x000D_
$("#panel :input").each(function(e){ _x000D_
  id = this.id;_x000D_
  // show id _x000D_
  console.log("#"+id);_x000D_
  // show input value _x000D_
  console.log(this.value);_x000D_
  // disable input if you want_x000D_
  //$("#"+id).prop('disabled', true);_x000D_
});
_x000D_
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>_x000D_
<div id="panel">_x000D_
  <table>_x000D_
    <tr>_x000D_
       <td><input id="Search_NazovProjektu" type="text" value="Naz Val" /></td>_x000D_
    </tr>_x000D_
    <tr>_x000D_
       <td><input id="Search_Popis" type="text" value="Po Val" /></td>_x000D_
    </tr>_x000D_
  </table>_x000D_
</div>
_x000D_
_x000D_
_x000D_

CertificateException: No name matching ssl.someUrl.de found

The server name should be same as the first/last name which you give while create a certificate

Break a previous commit into multiple commits

From git-rebase manual (SPLITTING COMMITS section)

In interactive mode, you can mark commits with the action "edit". However, this does not necessarily mean that git rebase expects the result of this edit to be exactly one commit. Indeed, you can undo the commit, or you can add other commits. This can be used to split a commit into two:

  • Start an interactive rebase with git rebase -i <commit>^, where <commit> is the commit you want to split. In fact, any commit range will do, as long as it contains that commit.

  • Mark the commit you want to split with the action "edit".

  • When it comes to editing that commit, execute git reset HEAD^. The effect is that the HEAD is rewound by one, and the index follows suit. However, the working tree stays the same.

  • Now add the changes to the index that you want to have in the first commit. You can use git add (possibly interactively) or git gui (or both) to do that.

  • Commit the now-current index with whatever commit message is appropriate now.

  • Repeat the last two steps until your working tree is clean.

  • Continue the rebase with git rebase --continue.

How do the post increment (i++) and pre increment (++i) operators work in Java?

++a increments a before it is evaluated. a++ evaluates a and then increments it.

Related to your expression given:

i = ((++a) + (++a) + (a++)) == ((6) + (7) + (7)); // a is 8 at the end
i = ((a++) + (++a) + (++a)) == ((5) + (7) + (8)); // a is 8 at the end

The parenteses I used above are implicitly used by Java. If you look at the terms this way you can easily see, that they are both the same as they are commutative.

Negation in Python

Python prefers English keywords to punctuation. Use not x, i.e. not os.path.exists(...). The same thing goes for && and || which are and and or in Python.

How to check if an object is an array?

You can check the type of your variable whether it is an array with;

var myArray=[];

if(myArray instanceof Array)
{
....
}

How to change the size of the radio button using CSS?

Here's one approach. By default the radio buttons were about twice as large as labels.
(See CSS and HTML code at end of answer)


Safari: 10.0.3

enter image description here


Chrome: 56.0.2924.87

enter image description here


Firefox: 50.1.0

enter image description here


Internet Explorer: 9 (Fuzziness not IE's fault, hosted test on netrenderer.com)

enter image description here


CSS:

.sortOptions > label {
    font-size:          8px;
}

.sortOptions > input[type=radio] {
    width:              10px;
    height:             10px;
}

HTML:

<div class="rightColumn">Answers
    <span class="sortOptions">
        <input type="radio" name="answerSortList" value="credate"/>
        <label for="credate">Creation</label>

        <input type="radio" name="answerSortList" value="lastact"/>
        <label for="lastact">Activity</label>

        <input type="radio" name="answerSortList" value="score"/>
        <label for="score">Score</label>

        <input type="radio" name="answerSortList" value="upvotes"/>
        <label for="upvotes">Up votes</label>

        <input type="radio" name="answerSortList" value="downvotes"/>
        <label for="downvotes">Down Votes</label>

        <input type="radio" name="answerSortList" value="accepted"/>
        <label for="downvotes">Accepted</label>

    </span>
</div>                

In Bootstrap open Enlarge image in modal

    <div class="row" style="display:inline-block">

    <div class="col-lg-12">
        <h1 class="page-header">Thumbnail Gallery</h1>

            <div class="col-lg-3 col-md-4 col-xs-6 thumb">
            <a class="thumbnail" href="#" data-image-id="" data-toggle="modal" data-title="This is my title" data-caption="Some lovely red flowers" data-image="http://onelive.us/wp-content/uploads/2014/08/flower-delivery-online.jpg" data-target="#image-gallery">
                <img class="img-responsive" src="http://onelive.us/wp-content/uploads/2014/08/flower-delivery-online.jpg" alt="Short alt text">
            </a>
        </div>
            <div class="col-lg-3 col-md-4 col-xs-6 thumb">
            <a class="thumbnail" href="#" data-image-id="" data-toggle="modal" data-title="The car i dream about" data-caption="If you sponsor me, I can drive this car" data-image="http://www.picturesnew.com/media/images/car-image.jpg" data-target="#image-gallery">
                <img class="img-responsive" src="http://www.picturesnew.com/media/images/car-image.jpg" alt="A alt text">
            </a>
        </div>
            <div class="col-lg-3 col-md-4 col-xs-6 thumb">
            <a class="thumbnail" href="#" data-image-id="" data-toggle="modal" data-title="Im so nice" data-caption="And if there is money left, my girlfriend will receive this car" data-image="http://upload.wikimedia.org/wikipedia/commons/7/78/1997_Fiat_Panda.JPG" data-target="#image-gallery">
                <img class="img-responsive" src="http://upload.wikimedia.org/wikipedia/commons/7/78/1997_Fiat_Panda.JPG" alt="Another alt text">
            </a>
        </div>
</div>


<div class="modal fade" id="image-gallery" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
    <div class="modal-dialog">
        <div class="modal-content">
            <div class="modal-header">
                <button type="button" class="close" data-dismiss="modal"><span aria-hidden="true">×</span><span class="sr-only">Close</span></button>
                <h4 class="modal-title" id="image-gallery-title"></h4>
            </div>
            <div class="modal-body">
                <img id="image-gallery-image" class="img-responsive" src="">
            </div>
            <div class="modal-footer">

                <div class="col-md-2">
                    <button type="button" class="btn btn-primary" id="show-previous-image">Previous</button>
                </div>

                <div class="col-md-8 text-justify" id="image-gallery-caption">
                    This text will be overwritten by jQuery
                </div>

                <div class="col-md-2">
                    <button type="button" id="show-next-image" class="btn btn-default">Next</button>
                </div>
            </div>
        </div>
    </div>
</div>



<script>
$(document).ready(function(){

    loadGallery(true, 'a.thumbnail');

    //This function disables buttons when needed
    function disableButtons(counter_max, counter_current){
        $('#show-previous-image, #show-next-image').show();
        if(counter_max == counter_current){
            $('#show-next-image').hide();
        } else if (counter_current == 1){
            $('#show-previous-image').hide();
        }
    }

    /**
     *
     * @param setIDs        Sets IDs when DOM is loaded. If using a PHP counter, set to false.
     * @param setClickAttr  Sets the attribute for the click handler.
     */

    function loadGallery(setIDs, setClickAttr){
        var current_image,
            selector,
            counter = 0;

        $('#show-next-image, #show-previous-image').click(function(){
            if($(this).attr('id') == 'show-previous-image'){
                current_image--;
            } else {
                current_image++;
            }

            selector = $('[data-image-id="' + current_image + '"]');
            updateGallery(selector);
        });

        function updateGallery(selector) {
            var $sel = selector;
            current_image = $sel.data('image-id');
            $('#image-gallery-caption').text($sel.data('caption'));
            $('#image-gallery-title').text($sel.data('title'));
            $('#image-gallery-image').attr('src', $sel.data('image'));
            disableButtons(counter, $sel.data('image-id'));
        }

        if(setIDs == true){
            $('[data-image-id]').each(function(){
                counter++;
                $(this).attr('data-image-id',counter);
            });
        }
        $(setClickAttr).on('click',function(){
            updateGallery($(this));
        });
    }
});
</script>

Why I can't access remote Jupyter Notebook server?

If you are still having trouble and you are running something like EC2 AWS instance, it may just be a case of opening the port through the AWS console.

see this answer

How to format DateTime columns in DataGridView?

If it is a windows form Datagrid, you could use the below code to format the datetime for a column

dataGrid.Columns[2].DefaultCellStyle.Format = "MM/dd/yyyy HH:mm:ss";

EDIT :

Apart from this, if you need the datetime in AM/PM format, you could use the below code

dataGrid.Columns[2].DefaultCellStyle.Format = "MM/dd/yyyy hh:mm:ss tt";

How do I get a button to open another activity?

If you declared your button in the xml file similar to this:

<Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="next activity"
        android:onClick="goToActivity2"
        />

then you can use it to change the activity by putting this at the java file:

public void goToActivity2 (View view){
    Intent intent = new Intent (this, Main2Activity.class);
    startActivity(intent);
}

Note that my second activity is called "Main2Activity"

How to store command results in a shell variable?

The syntax to store the command output into a variable is var=$(command).

So you can directly do:

result=$(ls -l | grep -c "rahul.*patle")

And the variable $result will contain the number of matches.

Jquery/Ajax Form Submission (enctype="multipart/form-data" ). Why does 'contentType:False' cause undefined index in PHP?

contentType option to false is used for multipart/form-data forms that pass files.

When one sets the contentType option to false, it forces jQuery not to add a Content-Type header, otherwise, the boundary string will be missing from it. Also, when submitting files via multipart/form-data, one must leave the processData flag set to false, otherwise, jQuery will try to convert your FormData into a string, which will fail.


To try and fix your issue:

Use jQuery's .serialize() method which creates a text string in standard URL-encoded notation.

You need to pass un-encoded data when using contentType: false.

Try using new FormData instead of .serialize():

  var formData = new FormData($(this)[0]);

See for yourself the difference of how your formData is passed to your php page by using console.log().

  var formData = new FormData($(this)[0]);
  console.log(formData);

  var formDataSerialized = $(this).serialize();
  console.log(formDataSerialized);

WPF Add a Border to a TextBlock

No, you need to wrap your TextBlock in a Border. Example:

<Border BorderThickness="1" BorderBrush="Black">
    <TextBlock ... />
</Border>

Of course, you can set these properties (BorderThickness, BorderBrush) through styles as well:

<Style x:Key="notCalledBorder" TargetType="{x:Type Border}">
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="BorderBrush" Value="Black" />
</Style>

<Border Style="{StaticResource notCalledBorder}">
    <TextBlock ... />
</Border>

AngularJS - Passing data between pages

You need to create a service to be able to share data between controllers.

app.factory('myService', function() {
 var savedData = {}
 function set(data) {
   savedData = data;
 }
 function get() {
  return savedData;
 }

 return {
  set: set,
  get: get
 }

});

In your controller A:

myService.set(yourSharedData);

In your controller B:

$scope.desiredLocation = myService.get();

Remember to inject myService in the controllers by passing it as a parameter.

Is there a way to check which CSS styles are being used or not used on a web page?

Without any third-party tools and any app, you can find unused CSS and javascript by using chrome dev tools in the coverage tab. read the post below from google developers. chrome coverage tab

If Else If In a Sql Server Function

I think you'd be better off with a CASE statement, which works a lot more like IF/ELSEIF

DECLARE @this int, @value varchar(10)
SET @this = 200
SET @value = (
SELECT 
CASE
    WHEN @this between 5 and 10 THEN 'foo'
    WHEN @this between 10 and 15 THEN 'bar'
    WHEN @this < 0 THEN 'barfoo'
    ELSE 'foofoo'
    END
)

More info: http://technet.microsoft.com/en-us/library/ms181765.aspx

Programmatically set TextBlock Foreground Color

To get the Color from Hex.

using System.Windows.Media;

Color color = (Color)ColorConverter.ConvertFromString("#FFDFD991");

and then set the foreground

textBlock.Foreground = new System.Windows.Media.SolidColorBrush(color); 

Remove 'b' character do in front of a string literal in Python 3

Here u Go

f = open('test.txt','rb+')
ch=f.read(1)
ch=str(ch,'utf-8')
print(ch)

Angular2 handling http response

The service :

import 'rxjs/add/operator/map';

import { Http } from '@angular/http';
import { Observable } from "rxjs/Rx"
import { Injectable } from '@angular/core';

@Injectable()
export class ItemService {
  private api = "your_api_url";

  constructor(private http: Http) {

  }

  toSaveItem(item) {
    return new Promise((resolve, reject) => {
      this.http
        .post(this.api + '/items', { item: item })
        .map(res => res.json())
        // This catch is very powerfull, it can catch all errors
        .catch((err: Response) => {
          // The err.statusText is empty if server down (err.type === 3)
          console.log((err.statusText || "Can't join the server."));
          // Really usefull. The app can't catch this in "(err)" closure
          reject((err.statusText || "Can't join the server."));
          // This return is required to compile but unuseable in your app
          return Observable.throw(err);
        })
        // The (err) => {} param on subscribe can't catch server down error so I keep only the catch
        .subscribe(data => { resolve(data) })
    })
  }
}

In the app :

this.itemService.toSaveItem(item).then(
  (res) => { console.log('success', res) },
  (err) => { console.log('error', err) }
)

CSS selector for text input fields?

You can use the attribute selector here:

input[type="text"] {
    font-family: Arial, sans-serif;
}

This is supported in IE7 and above. You can use IE7.js to add support for this if you need to support IE6.

See: http://reference.sitepoint.com/css/attributeselector for more information

Iterating through a list to render multiple widgets in Flutter?

For googler, I wrote a simple Stateless Widget containing 3 method mentioned in this SO. Hope this make it easier to understand.

import 'package:flutter/material.dart';

class ListAndFP extends StatelessWidget {
  final List<String> items = ['apple', 'banana', 'orange', 'lemon'];

  //  for in (require dart 2.2.2 SDK or later)
  Widget method1() {
    return Column(
      children: <Widget>[
        Text('You can put other Widgets here'),
        for (var item in items) Text(item),
      ],
    );
  }

  // map() + toList() + Spread Property
  Widget method2() {
    return Column(
      children: <Widget>[
        Text('You can put other Widgets here'),
        ...items.map((item) => Text(item)).toList(),
      ],
    );
  }

  // map() + toList()
  Widget method3() {
    return Column(
      // Text('You CANNOT put other Widgets here'),
      children: items.map((item) => Text(item)).toList(),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: method1(),
    );
  }
}

Send a ping to each IP on a subnet

I would suggest the use of fping with the mask option, since you are not restricting yourself in ping.

fping -g 192.168.1.0/24

The response will be easy to parse in a script:

192.168.1.1 is alive
192.168.1.2 is alive
192.168.1.3 is alive
192.168.1.5 is alive
...
192.168.1.4 is unreachable
192.168.1.6 is unreachable
192.168.1.7 is unreachable
...

Note: Using the argument -a will restrict the output to reachable ip addresses, you may want to use it otherwise fping will also print unreachable addresses:

fping -a -g 192.168.1.0/24

From man:

fping differs from ping in that you can specify any number of targets on the command line, or specify a file containing the lists of targets to ping. Instead of sending to one target until it times out or replies, fping will send out a ping packet and move on to the next target in a round-robin fashion.

More info: http://fping.org/

CentOS 7 and Puppet unable to install nc

yum install nmap-ncat.x86_64

resolved my problem

Laravel Rule Validation for Numbers

$this->validate($request,[
        'input_field_name'=>'digits_between:2,5',
       ]);

Try this it will be work

How to call a vue.js function on page load

If you get data in array you can do like below. It's worked for me

    <template>
    {{ id }}
    </template>
    <script>

    import axios from "axios";

        export default {
            name: 'HelloWorld',
            data () {
                return {
                    id: "",

                }
            },
    mounted() {
                axios({ method: "GET", "url": "https://localhost:42/api/getdata" }).then(result => {
                    console.log(result.data[0].LoginId);
                    this.id = result.data[0].LoginId;
                }, error => {
                    console.error(error);
                });
            },
</script>

Printing to the console in Google Apps Script?

Even though Logger.log() is technically the correct way to output something to the console, it has a few annoyances:

  1. The output can be an unstructured mess and hard to quickly digest.
  2. You have to first run the script, then click View / Logs, which is two extra clicks (one if you remember the Ctrl+Enter keyboard shortcut).
  3. You have to insert Logger.log(playerArray), and then after debugging you'd probably want to remove Logger.log(playerArray), hence an additional 1-2 more steps.
  4. You have to click on OK to close the overlay (yet another extra click).

Instead, whenever I want to debug something I add breakpoints (click on line number) and press the Debug button (bug icon). Breakpoints work well when you are assigning something to a variable, but not so well when you are initiating a variable and want to peek inside of it at a later point, which is similar to what the op is trying to do. In this case, I would force a break condition by entering "x" (x marks the spot!) to throw a run-time error:

enter image description here

Compare with viewing Logs:

enter image description here

The Debug console contains more information and is a lot easier to read than the Logs overlay. One minor benefit with this method is that you never have to worry about polluting your code with a bunch of logging commands if keeping clean code is your thing. Even if you enter "x", you are forced to remember to remove it as part of the debugging process or else your code won't run (built-in cleanup measure, yay).

Remove all files except some from a directory

Rather than going for a direct command, please move required files to temp dir outside current dir. Then delete all files using rm * or rm -r *.

Then move required files to current dir.

What's "P=NP?", and why is it such a famous question?

To give the simplest answer I can think of:

Suppose we have a problem that takes a certain number of inputs, and has various potential solutions, which may or may not solve the problem for given inputs. A logic puzzle in a puzzle magazine would be a good example: the inputs are the conditions ("George doesn't live in the blue or green house"), and the potential solution is a list of statements ("George lives in the yellow house, grows peas, and owns the dog"). A famous example is the Traveling Salesman problem: given a list of cities, and the times to get from any city to any other, and a time limit, a potential solution would be a list of cities in the order the salesman visits them, and it would work if the sum of the travel times was less than the time limit.

Such a problem is in NP if we can efficiently check a potential solution to see if it works. For example, given a list of cities for the salesman to visit in order, we can add up the times for each trip between cities, and easily see if it's under the time limit. A problem is in P if we can efficiently find a solution if one exists.

(Efficiently, here, has a precise mathematical meaning. Practically, it means that large problems aren't unreasonably difficult to solve. When searching for a possible solution, an inefficient way would be to list all possible potential solutions, or something close to that, while an efficient way would require searching a much more limited set.)

Therefore, the P=NP problem can be expressed this way: If you can verify a solution for a problem of the sort described above efficiently, can you find a solution (or prove there is none) efficiently? The obvious answer is "Why should you be able to?", and that's pretty much where the matter stands today. Nobody has been able to prove it one way or another, and that bothers a lot of mathematicians and computer scientists. That's why anybody who can prove the solution is up for a million dollars from the Claypool Foundation.

We generally assume that P does not equal NP, that there is no general way to find solutions. If it turned out that P=NP, a lot of things would change. For example, cryptography would become impossible, and with it any sort of privacy or verifiability on the Internet. After all, we can efficiently take the encrypted text and the key and produce the original text, so if P=NP we could efficiently find the key without knowing it beforehand. Password cracking would become trivial. On the other hand, there's whole classes of planning problems and resource allocation problems that we could solve effectively.

You may have heard the description NP-complete. An NP-complete problem is one that is NP (of course), and has this interesting property: if it is in P, every NP problem is, and so P=NP. If you could find a way to efficiently solve the Traveling Salesman problem, or logic puzzles from puzzle magazines, you could efficiently solve anything in NP. An NP-complete problem is, in a way, the hardest sort of NP problem.

So, if you can find an efficient general solution technique for any NP-complete problem, or prove that no such exists, fame and fortune are yours.

How do format a phone number as a String in Java?

You can use String.replaceFirst with regex method like

    long phoneNum = 123456789L;
    System.out.println(String.valueOf(phoneNum).replaceFirst("(\\d{3})(\\d{3})(\\d+)", "($1)-$2-$3"));

C# Form.Close vs Form.Dispose

Close() - managed resource can be temporarily closed and can be opened once again.

Dispose() - permanently removes managed or not managed resource

Setting selection to Nothing when programming Excel

I do not think that this can be done. Here is some code copied with no modifications from Chip Pearson's site: http://www.cpearson.com/excel/UnSelect.aspx.

UnSelectActiveCell

This procedure will remove the Active Cell from the Selection.

Sub UnSelectActiveCell()
    Dim R As Range
    Dim RR As Range
    For Each R In Selection.Cells
        If StrComp(R.Address, ActiveCell.Address, vbBinaryCompare) <> 0 Then
            If RR Is Nothing Then
                Set RR = R
            Else
                Set RR = Application.Union(RR, R)
            End If
        End If
    Next R
    If Not RR Is Nothing Then
        RR.Select
    End If
End Sub

UnSelectCurrentArea

This procedure will remove the Area containing the Active Cell from the Selection.

Sub UnSelectCurrentArea()
    Dim Area As Range
    Dim RR As Range

    For Each Area In Selection.Areas
        If Application.Intersect(Area, ActiveCell) Is Nothing Then
            If RR Is Nothing Then
                Set RR = Area
            Else
                Set RR = Application.Union(RR, Area)
            End If
        End If
    Next Area
    If Not RR Is Nothing Then
        RR.Select
    End If
End Sub

Interface type check with Typescript

I found an example from @progress/kendo-data-query in file filter-descriptor.interface.d.ts

Checker

declare const isCompositeFilterDescriptor: (source: FilterDescriptor | CompositeFilterDescriptor) => source is CompositeFilterDescriptor;

Example usage

const filters: Array<FilterDescriptor | CompositeFilterDescriptor> = filter.filters;

filters.forEach((element: FilterDescriptor | CompositeFilterDescriptor) => {
    if (isCompositeFilterDescriptor(element)) {
        // element type is CompositeFilterDescriptor
    } else {
        // element type is FilterDescriptor
    }
});

For-loop vs while loop in R

Because 1 is numeric, but not integer (i.e. it's a floating point number), and 1:6000 is numeric and integer.

> print(class(1))
[1] "numeric"
> print(class(1:60000))
[1] "integer"

60000 squared is 3.6 billion, which is NOT representable in signed 32-bit integer, hence you get an overflow error:

> as.integer(60000)*as.integer(60000)
[1] NA
Warning message:
In as.integer(60000) * as.integer(60000) : NAs produced by integer overflow

3.6 billion is easily representable in floating point, however:

> as.single(60000)*as.single(60000)
[1] 3.6e+09

To fix your for code, convert to a floating point representation:

function (N)
{
    for(i in as.single(1:N)) {
        y <- i*i
    }
}

How to calculate UILabel width based on text length?

Here's something I came up with after applying a few principles other SO posts, including Aaron's link:

AnnotationPin *myAnnotation = (AnnotationPin *)annotation;

self = [super initWithAnnotation:myAnnotation reuseIdentifier:reuseIdentifier];
self.backgroundColor = [UIColor greenColor];
self.frame = CGRectMake(0,0,30,30);
imageView = [[UIImageView alloc] initWithImage:myAnnotation.THEIMAGE];
imageView.frame = CGRectMake(3,3,20,20);
imageView.layer.masksToBounds = NO;
[self addSubview:imageView];
[imageView release];

CGSize titleSize = [myAnnotation.THETEXT sizeWithFont:[UIFont systemFontOfSize:12]];
CGRect newFrame = self.frame;
newFrame.size.height = titleSize.height + 12;
newFrame.size.width = titleSize.width + 32;
self.frame = newFrame;
self.layer.borderColor = [UIColor colorWithRed:0 green:.3 blue:0 alpha:1.0f].CGColor;
self.layer.borderWidth = 3.0;
        
UILabel *infoLabel = [[UILabel alloc] initWithFrame:CGRectMake(26,5,newFrame.size.width-32,newFrame.size.height-12)];
infoLabel.text = myAnnotation.title;
infoLabel.backgroundColor = [UIColor clearColor];
infoLabel.textColor = [UIColor blackColor];
infoLabel.textAlignment = UITextAlignmentCenter;
infoLabel.font = [UIFont systemFontOfSize:12];

[self addSubview:infoLabel];
[infoLabel release];

In this example, I'm adding a custom pin to a MKAnnotation class that resizes a UILabel according to the text size. It also adds an image on the left side of the view, so you see some of the code managing the proper spacing to handle the image and padding.

The key is to use CGSize titleSize = [myAnnotation.THETEXT sizeWithFont:[UIFont systemFontOfSize:12]]; and then redefine the view's dimensions. You can apply this logic to any view.

Although Aaron's answer works for some, it didn't work for me. This is a far more detailed explanation that you should try immediately before going anywhere else if you want a more dynamic view with an image and resizable UILabel. I already did all the work for you!!

Best way to move files between S3 buckets?

I know this is an old thread but for others who reach there my suggestion is to create a scheduled job to copy content from production bucket to development one.

You can use If you use .NET this article might help you

https://edunyte.com/2015/03/aws-s3-copy-object-from-one-bucket-or/

how to set ul/li bullet point color?

I believe this is controlled by the css color property applied to the element.

Getting the source HTML of the current page from chrome extension

Here is my solution:

chrome.runtime.onMessage.addListener(function(request, sender) {
        if (request.action == "getSource") {
            this.pageSource = request.source;
            var title = this.pageSource.match(/<title[^>]*>([^<]+)<\/title>/)[1];
            alert(title)
        }
    });

    chrome.tabs.query({ active: true, currentWindow: true }, tabs => {
        chrome.tabs.executeScript(
            tabs[0].id,
            { code: 'var s = document.documentElement.outerHTML; chrome.runtime.sendMessage({action: "getSource", source: s});' }
        );
    });

How do I share variables between different .c files?

The 2nd file needs to know about the existance of your variable. To do this you declare the variable again but use the keyword extern in front of it. This tells the compiler that the variable is available but declared somewhere else, thus prevent instanciating it (again, which would cause clashes when linking). While you can put the extern declaration in the C file itself it's common style to have an accompanying header (i.e. .h) file for each .c file that provides functions or variables to others which hold the extern declaration. This way you avoid copying the extern declaration, especially if it's used in multiple other files. The same applies for functions, though you don't need the keyword extern for them.

That way you would have at least three files: the source file that declares the variable, it's acompanying header that does the extern declaration and the second source file that #includes the header to gain access to the exported variable (or any other symbol exported in the header). Of course you need all source files (or the appropriate object files) when trying to link something like that, as the linker needs to resolve the symbol which is only possible if it actually exists in the files linked.

How to find Control in TemplateField of GridView?

I have done it accessing the controls inside the cell control. Find in all control collections.

 ControlCollection cc = (ControlCollection)e.Row.Controls[1].Controls;

 Label lbCod = (Label)cc[1];

Running an outside program (executable) in Python?

Is that trying to execute C:\Documents with arguments of "and", "Settings/flow_model/flow.exe"?

Also, you might consider subprocess.call().

#1273 - Unknown collation: 'utf8mb4_unicode_ci' cPanel

In my case it turns out my
new server was running MySQL 5.5,
old server was running MySQL 5.6.
So I got this error when trying to import the .sql file I'd exported from my old server.

MySQL 5.5 does not support utf8mb4_unicode_520_ci, but
MySQL 5.6 does.

Updating to MySQL 5.6 on the new server solved collation the error !

If you want to retain MySQL 5.5, you can:
- make a copy of your exported .sql file
- replace instances of utf8mb4unicode520_ci and utf8mb4_unicode_520_ci
...with utf8mb4_unicode_ci
- import your updated .sql file.

Bootstrap 3: Text overlay on image

Is this what you're after?

http://jsfiddle.net/dCNXU/1/

I added :text-align:center to the div and image

Return a 2d array from a function

I would suggest you Matrix library as an open source tool for c++, its usage is like arrays in c++. Here you can see documention.

Matrix funcionName(){

    Matrix<int> arr(2, 2);

    arr[0][0] = 5;
    arr[0][1] = 10;
    arr[1][0] = 0;
    arr[1][1] = 44;

    return arr;
}

What is the most efficient way to create HTML elements using jQuery?

If you have a lot of HTML content (more than just a single div), you might consider building the HTML into the page within a hidden container, then updating it and making it visible when needed. This way, a large portion of your markup can be pre-parsed by the browser and avoid getting bogged down by JavaScript when called. Hope this helps!

Python timedelta in years

If you're trying to check if someone is 18 years of age, using timedelta will not work correctly on some edge cases because of leap years. For example, someone born on January 1, 2000, will turn 18 exactly 6575 days later on January 1, 2018 (5 leap years included), but someone born on January 1, 2001, will turn 18 exactly 6574 days later on January 1, 2019 (4 leap years included). Thus, you if someone is exactly 6574 days old, you can't determine if they are 17 or 18 without knowing a little more information about their birthdate.

The correct way to do this is to calculate the age directly from the dates, by subtracting the two years, and then subtracting one if the current month/day precedes the birth month/day.

Vertically align text next to an image?

For the record, alignment "commands" shouldn't work on a SPAN, because it is an in-line tag, not a block-level tag. Things like alignment, margin, padding, etc won't work on an in-line tag because the point of inline is not to disrupt the text flow.

CSS divides HTML tags up into two groups: in-line and block-level. Search "css block vs inline" and a great article shows up...

http://www.webdesignfromscratch.com/html-css/css-block-and-inline/

(Understanding core CSS principles is a key to it not being quite so annoying)

How to include clean target in Makefile?

In makefile language $@ means "name of the target", so rm -f $@ translates to rm -f clean.

You need to specify to rm what exactly you want to delete, like rm -f *.o code1 code2

How to completely remove node.js from Windows

I came here because the Remove button was not available from Add/Remove programs. It was saying "Node.js cannot be removed".

This worked:

  1. Got the .msi of my installed Node version. Ran it to repair the installation just in case.
  2. Opened the Administrator command prompt and ran msiexec /uninstall <node.msi>.

Using an HTTP PROXY - Python

I encountered this on jython client. The server was only talking TLS and the client using SSL context.

javax.net.ssl.SSLContext.getInstance("SSL")

Once the client was to TLS, things started working.

How to SHA1 hash a string in Android?

Totally based on @Whymarrh's answer, this is my implementation, tested and working fine, no dependencies:

public static String getSha1Hex(String clearString)
{
    try
    {
        MessageDigest messageDigest = MessageDigest.getInstance("SHA-1");
        messageDigest.update(clearString.getBytes("UTF-8"));
        byte[] bytes = messageDigest.digest();
        StringBuilder buffer = new StringBuilder();
        for (byte b : bytes)
        {
            buffer.append(Integer.toString((b & 0xff) + 0x100, 16).substring(1));
        }
        return buffer.toString();
    }
    catch (Exception ignored)
    {
        ignored.printStackTrace();
        return null;
    }
}

Difference between setTimeout with and without quotes and parentheses

    ##If i want to wait for some response from server or any action we use setTimeOut.

    functionOne =function(){
    console.info("First");

    setTimeout(()=>{
    console.info("After timeOut 1");
    },5000);
    console.info("only setTimeOut() inside code waiting..");
    }

    functionTwo =function(){
    console.info("second");
    }
    functionOne();
    functionTwo();

## So here console.info("After timeOut 1"); will be executed after time elapsed.
Output:
******************************************************************************* 
First
only setTimeOut() inside code waiting..
second
undefined
After timeOut 1  // executed after time elapsed.

How to specify maven's distributionManagement organisation wide?

Regarding the answer from Michael Wyraz, where you use alt*DeploymentRepository in your settings.xml or command on the line, be careful if you are using version 3.0.0-M1 of the maven-deploy-plugin (which is the latest version at the time of writing), there is a bug in this version that could cause a server authentication issue.

A workaround is as follows. In the value:

releases::default::https://YOUR_NEXUS_URL/releases

you need to remove the default section, making it:

releases::https://YOUR_NEXUS_URL/releases

The prior version 2.8.2 does not have this bug.

Permission is only granted to system app

Path In Android Studio in mac:

Android Studio -> Preferences -> Editor -> Inspections

Expand Android -> Expand Lint -> Expand Correctness

Uncheck the checkbox for Using system app permission

Click on "APPLY" -> "OK"

How Can I Resolve:"can not open 'git-upload-pack' " error in eclipse?

I got this Error after re-creating a Repository on my Server (Codebeamer) - the User in Question lacked some permissions, after granting them, everything worked fine.

Struct Constructor in C++?

Yes it possible to have constructor in structure here is one example:

#include<iostream.h> 
struct a {
  int x;
  a(){x=100;}
};

int main() {
  struct a a1;
  getch();
}

Check if at least two out of three booleans are true

Ternary operators get the nerd juices flowing, but they can be confusing (making code less maintainable, thus increasing the potential for bug injection). Jeff Attwood said it well here:

It's a perfect example of trading off an utterly meaningless one time write-time savings against dozens of read-time comprehension penalties-- It Makes Me Think.

Avoiding ternary operators, I've created the following function:

function atLeastTwoTrue($a, $b, $c) {
        $count = 0;

        if ($a) { $count++; }
        if ($b) { $count++; }
        if ($c) { $count++; }

        if ($count >= 2) {
                return true;
        } else {
                return false;
        }
}

Is this as cool as some of the other solutions? No. Is it easier to understand? Yes. Will that lead to more maintainable, less buggy code? Yes.

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

As an addition, if have Sublime Text installed in your development computer, you can drag the file to your opened Sublime Text window, right click the filename -> rename and enter whatever name even without any extension. This worked for me.

Make copy of an array

If you want to make a copy of:

int[] a = {1,2,3,4,5};

This is the way to go:

int[] b = Arrays.copyOf(a, a.length);

Arrays.copyOf may be faster than a.clone() on small arrays. Both copy elements equally fast but clone() returns Object so the compiler has to insert an implicit cast to int[]. You can see it in the bytecode, something like this:

ALOAD 1
INVOKEVIRTUAL [I.clone ()Ljava/lang/Object;
CHECKCAST [I
ASTORE 2

Read lines from a file into a Bash array

Latest revision based on comment from BinaryZebra's comment and tested here. The addition of command eval allows for the expression to be kept in the present execution environment while the expressions before are only held for the duration of the eval.

Use $IFS that has no spaces\tabs, just newlines/CR

$ IFS=$'\r\n' GLOBIGNORE='*' command eval  'XYZ=($(cat /etc/passwd))'
$ echo "${XYZ[5]}"
sync:x:5:0:sync:/sbin:/bin/sync

Also note that you may be setting the array just fine but reading it wrong - be sure to use both double-quotes "" and braces {} as in the example above


Edit:

Please note the many warnings about my answer in comments about possible glob expansion, specifically gniourf-gniourf's comments about my prior attempts to work around

With all those warnings in mind I'm still leaving this answer here (yes, bash 4 has been out for many years but I recall that some macs only 2/3 years old have pre-4 as default shell)

Other notes:

Can also follow drizzt's suggestion below and replace a forked subshell+cat with

$(</etc/passwd)

The other option I sometimes use is just set IFS into XIFS, then restore after. See also Sorpigal's answer which does not need to bother with this

How do I reset the scale/zoom of a web app on an orientation change on the iPhone?

I created a working demo of a landscape/portrait layout but the zoom must be disabled for it to work without JavaScript:

http://matthewjamestaylor.com/blog/ipad-layout-with-landscape-portrait-modes

Find the most frequent number in a NumPy array

Performances (using iPython) for some solutions found here:

>>> # small array
>>> a = [12,3,65,33,12,3,123,888000]
>>> 
>>> import collections
>>> collections.Counter(a).most_common()[0][0]
3
>>> %timeit collections.Counter(a).most_common()[0][0]
100000 loops, best of 3: 11.3 µs per loop
>>> 
>>> import numpy
>>> numpy.bincount(a).argmax()
3
>>> %timeit numpy.bincount(a).argmax()
100 loops, best of 3: 2.84 ms per loop
>>> 
>>> import scipy.stats
>>> scipy.stats.mode(a)[0][0]
3.0
>>> %timeit scipy.stats.mode(a)[0][0]
10000 loops, best of 3: 172 µs per loop
>>> 
>>> from collections import defaultdict
>>> def jjc(l):
...     d = defaultdict(int)
...     for i in a:
...         d[i] += 1
...     return sorted(d.iteritems(), key=lambda x: x[1], reverse=True)[0]
... 
>>> jjc(a)[0]
3
>>> %timeit jjc(a)[0]
100000 loops, best of 3: 5.58 µs per loop
>>> 
>>> max(map(lambda val: (a.count(val), val), set(a)))[1]
12
>>> %timeit max(map(lambda val: (a.count(val), val), set(a)))[1]
100000 loops, best of 3: 4.11 µs per loop
>>> 

Best is 'max' with 'set' for small arrays like the problem.

According to @David Sanders, if you increase the array size to something like 100,000 elements, the "max w/set" algorithm ends up being the worst by far whereas the "numpy bincount" method is the best.

How to get all of the immediate subdirectories in Python

I just wrote some code to move vmware virtual machines around, and ended up using os.path and shutil to accomplish file copying between sub-directories.

def copy_client_files (file_src, file_dst):
    for file in os.listdir(file_src):
            print "Copying file: %s" % file
            shutil.copy(os.path.join(file_src, file), os.path.join(file_dst, file))

It's not terribly elegant, but it does work.

Setting POST variable without using form

If you want to set $_POST['text'] to another value, why not use:

$_POST['text'] = $var;

on next.php?

How to concatenate strings in django templates?

Refer to Concatenating Strings in Django Templates:

  1. For earlier versions of Django:

    {{ "Mary had a little"|stringformat:"s lamb." }}

"Mary had a little lamb."

  1. Else:

    {{ "Mary had a little"|add:" lamb." }}

"Mary had a little lamb."

Opening a .ipynb.txt File

If you have a unix/linux system I'd just rename the file via command line

mv file_name.pynb.txt file_name.ipynb

worked like a charm for me!

Adding css class through aspx code behind

BtnAdd.CssClass = "BtnCss";

BtnCss should be present in your Css File.

(reference of that Css File name should be added to the aspx if needed)

Get selected key/value of a combo box using jQuery

$(this).find("select").each(function () {
    $(this).find('option:selected').text();
});

Python Socket Multiple Clients

This program will open 26 sockets where you would be able to connect a lot of TCP clients to it.

#!usr/bin/python
from thread import *
import socket
import sys

def clientthread(conn):
    buffer=""
    while True:
        data = conn.recv(8192)
        buffer+=data
        print buffer
    #conn.sendall(reply)
    conn.close()

def main():
    try:
        host = '192.168.1.3'
        port = 6666
        tot_socket = 26
        list_sock = []
        for i in range(tot_socket):
            s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            s.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
            s.bind((host, port+i))
            s.listen(10)
            list_sock.append(s)
            print "[*] Server listening on %s %d" %(host, (port+i))

        while 1:
            for j in range(len(list_sock)):
                conn, addr = list_sock[j].accept()
                print '[*] Connected with ' + addr[0] + ':' + str(addr[1])
                start_new_thread(clientthread ,(conn,))
        s.close()

    except KeyboardInterrupt as msg:
        sys.exit(0)


if __name__ == "__main__":
    main()

Java Embedded Databases Comparison

I have used Derby and i really hate it's data type conversion functions, especially date/time functions. (Number Type)<--> Varchar conversion it's a pain.

So that if you plan use data type conversions in your DB statements consider the use of othe embedded DB, i learn it too late.

Latest Derby Version data type conversions

Font Awesome not working, icons showing as squares

I use the Official Font Awesome SASS Ruby Gem and fixed the error by adding the below line to my application.css.scss

@import "font-awesome-sprockets";

Explanation:

The font-awesome-sprockets file includes the sprockets assest helper Sass functions used for finding the proper path to the font file.

Laravel 5.2 redirect back with success message

In Controller

return redirect()->route('company')->with('update', 'Content has been updated successfully!');

In view

@if (session('update'))
  <div class="alert alert-success alert-dismissable custom-success-box" style="margin: 15px;">
     <a href="#" class="close" data-dismiss="alert" aria-label="close">&times;</a>
     <strong> {{ session('update') }} </strong>
  </div>
@endif

Setting Java heap space under Maven 2 on Windows

On the Mac: Instead of JAVA_OPTS and MAVEN_OPTS, use _JAVA_OPTIONS instead. This works!

Using Chrome's Element Inspector in Print Preview Mode?

As of Chrome 48+, you can access the print preview via the following steps:

  1. Open dev tools – Ctrl/Cmd + Shift + I or right click on the page and choose 'Inspect'.

  2. Hit Esc to open the additional drawer.

  3. If 'Rendering' isn't already being show, click the 3 dot kebab and choose 'rendering'.

  4. Check the 'Emulate print media' checkbox.

From there Chrome will show you a print version of your page and you can inspect element and troubleshoot like you would the browser version.

Image of Chrome 49+ Print Preview option in Dev Tools

Why does Java have transient fields?

A field which is declare with transient modifier it will not take part in serialized process. When an object is serialized(saved in any state), the values of its transient fields are ignored in the serial representation, while the field other than transient fields will take part in serialization process. That is the main purpose of the transient keyword.

String concatenation: concat() vs "+" operator

Tom is correct in describing exactly what the + operator does. It creates a temporary StringBuilder, appends the parts, and finishes with toString().

However, all of the answers so far are ignoring the effects of HotSpot runtime optimizations. Specifically, these temporary operations are recognized as a common pattern and are replaced with more efficient machine code at run-time.

@marcio: You've created a micro-benchmark; with modern JVM's this is not a valid way to profile code.

The reason run-time optimization matters is that many of these differences in code -- even including object-creation -- are completely different once HotSpot gets going. The only way to know for sure is profiling your code in situ.

Finally, all of these methods are in fact incredibly fast. This might be a case of premature optimization. If you have code that concatenates strings a lot, the way to get maximum speed probably has nothing to do with which operators you choose and instead the algorithm you're using!

How to use JQuery with ReactJS

To install it, just run the command

npm install jquery

or

yarn add jquery

then you can import it in your file like

import $ from 'jquery';

What is a callback URL in relation to an API?

A callback URL will be invoked by the API method you're calling after it's done. So if you call

POST /api.example.com/foo?callbackURL=http://my.server.com/bar

Then when /foo is finished, it sends a request to http://my.server.com/bar. The contents and method of that request are going to vary - check the documentation for the API you're accessing.

How do I remove blank pages coming between two chapters in Appendix?

If you specify the option 'openany' in the \documentclass declaration each chapter in the book (I'm guessing you're using the book class as chapters open on the next page in reports and articles don't have chapters) will open on a new page, not necessarily the next odd-numbered page.

Of course, that's not quite what you want. I think you want to set openany for chapters in the appendix. 'fraid I don't know how to do that, I suspect that you need to roll up your sleeves and wrestle with TeX itself

Caused by: org.flywaydb.core.api.FlywayException: Validate failed. Migration Checksum mismatch for migration 2

Flyway is comparing the checksum of the SQL script with that of the previously run checksum. This exception typically occurs if you change a SQL script that has already been applied by Flyway, thus causing a checksum mismatch.

If this is development, you can drop your database and start the migrations from scratch.

If you're in production, never edit SQL scripts that have already been applied. Only create new SQL scripts going forward.

How do I perform an IF...THEN in an SQL SELECT?

 SELECT
   CASE 
      WHEN OBSOLETE = 'N' or InStock = 'Y' THEN 'TRUE' 
      ELSE 'FALSE' 
   END AS Salable,
   * 
FROM PRODUCT

Function in JavaScript that can be called only once

If you want to be able to reuse the function in the future then this works well based on ed Hopp's code above (I realize that the original question didn't call for this extra feature!):

   var something = (function() {
   var executed = false;              
    return function(value) {
        // if an argument is not present then
        if(arguments.length == 0) {               
            if (!executed) {
            executed = true;
            //Do stuff here only once unless reset
            console.log("Hello World!");
            }
            else return;

        } else {
            // otherwise allow the function to fire again
            executed = value;
            return;
        }       
    }
})();

something();//Hello World!
something();
something();
console.log("Reset"); //Reset
something(false);
something();//Hello World!
something();
something();

The output look like:

Hello World!
Reset
Hello World!

Iterate two Lists or Arrays with one ForEach statement in C#

Since C# 7, you can use Tuples...

int[] nums = { 1, 2, 3, 4 };
string[] words = { "one", "two", "three", "four" };

foreach (var tuple in nums.Zip(words, (x, y) => (x, y)))
{
    Console.WriteLine($"{tuple.Item1}: {tuple.Item2}");
}

// or...
foreach (var tuple in nums.Zip(words, (x, y) => (Num: x, Word: y)))
{
    Console.WriteLine($"{tuple.Num}: {tuple.Word}");
}

How to len(generator())

You can len(list(generator)) but you could probably make something more efficient if you really intend to discard the results.

Send Outlook Email Via Python?

using pywin32:

from win32com.client import Dispatch

session = Dispatch('MAPI.session')
session.Logon('','',0,1,0,0,'exchange.foo.com\nUserName');
msg = session.Outbox.Messages.Add('Hello', 'This is a test')
msg.Recipients.Add('Corey', 'SMTP:[email protected]')
msg.Send()
session.Logoff()

"Expected BEGIN_OBJECT but was STRING at line 1 column 1"

Don't forget to convert your object into Json first using Gson()

  val fromUserJson = Gson().toJson(notificationRequest.fromUser)

Then you can easily convert it back into an object using this awesome library

      val fromUser = Gson().fromJson(fromUserJson, User::class.java)