Programs & Examples On #Rowfilter

0

How to filter data in dataview

Eg:

Datatable newTable =  new DataTable();

            foreach(string s1 in list)
            {
                if (s1 != string.Empty) {
                    dvProducts.RowFilter = "(CODE like '" + serachText + "*') AND (CODE <> '" + s1 + "')";
                    foreach(DataRow dr in dvProducts.ToTable().Rows)
                    {
                       newTable.ImportRow(dr);
                    }
                }
            }
ListView1.DataSource = newTable;
ListView1.DataBind();

Filtering DataGridView without changing datasource

For those of you how have implemented the checked answer yet still getting the error

(Object reference not set to an instance of an object)

As was mentioned in the comments, maybe the DataGridView's data source is not of the type DataTable, but if it is, try to assign the data table to the DataGridView's data source again. In my case, I assigned the data table to the DataGridView in FormLoad() and when I write this code

(dataGridViewFields.DataSource as DataTable).DefaultView.RowFilter = string.Format("Field = '{0}'", textBoxFilter.Text);

it was giving me the error I mentioned above. So, I reassigned the data table to the dgv again. So the code was something like

dataGridViewFields.DataSource = Dt;
(dataGridViewFields.DataSource as DataTable).DefaultView.RowFilter = string.Format("Field = '{0}'", textBoxFilter.Text);

And it worked.

sql server #region

BEGIN...END works, you just have to add a commented section. The easiest way to do this is to add a section name! Another route is to add a comment block. See below:

BEGIN  -- Section Name
/* 
Comment block some stuff  --end comment should be on next line
*/

 --Very long query
SELECT * FROM FOO
SELECT * FROM BAR
END

Async image loading from url inside a UITableView cell - image changes to wrong image while scrolling

The best answer is not the correct way to do this :(. You actually bound indexPath with model, which is not always good. Imagine that some rows has been added during loading image. Now cell for given indexPath exists on screen, but the image is no longer correct! The situation is kinda unlikely and hard to replicate but it's possible.

It's better to use MVVM approach, bind cell with viewModel in controller and load image in viewModel (assigning ReactiveCocoa signal with switchToLatest method), then subscribe this signal and assign image to cell! ;)

You have to remember to not abuse MVVM. Views have to be dead simple! Whereas ViewModels should be reusable! It's why it's very important to bind View (UITableViewCell) and ViewModel in controller.

Reading HTML content from a UIWebView

(Xcode 5 iOS 7) Universal App example for iOS 7 and Xcode 5. It is an open source project / example located here: Link to SimpleWebView (Project Zip and Source Code Example)

Change name of folder when cloning from GitHub?

In case you want to clone a specific branch only, then,

git clone -b <branch-name> <repo-url> <destination-folder-name>

for example,

git clone -b dev https://github.com/sferik/sign-in-with-twitter.git signin

How to open a Bootstrap modal window using jQuery?

<script type="text/javascript">
    $(function () {
        $("mybtn").click(function () {
            $("#my-modal").modal("show");
        });
    });
</script>

How to use OpenSSL to encrypt/decrypt files?

Additional comments to mti2935 good answer.

It seems the higher iteration the better protection against brute force, and you should use a high iteration as you can afford performance/resource wise.

On my my old Intel i3-7100 encrypting a rather big file 1.5GB:

 time openssl enc -aes256 -e -pbkdf2 -iter 10000 -pass pass:"mypassword" -in "InputFile" -out "OutputFile"
 Seconds: 2,564s

 time openssl enc -aes256 -e -pbkdf2 -iter 262144 -pass pass:"mypassword" -in "InputFile" -out "OutputFile"
 Seconds:  2,775s

Not really any difference, didn't check memory usage though(?)

With today's GPUs, and even faster tomorrows, I guess billion brute-force iteration seems possible every seconds.

12 years ago a NVIDIA GeForce 8800 Ultra could iterate over 200.000 millions/sec iterations (MD5 hashing though)

source: Ainane-Barrett-Johnson-Vivar-OpenSSL.pdf

mailto link multiple body lines

  1. Use a single body parameter within the mailto string
  2. Use %0D%0A as newline

The mailto URI Scheme is specified by by RFC2368 (July 1998) and RFC6068 (October 2010).
Below is an extract of section 5 of this last RFC:

[...] line breaks in the body of a message MUST be encoded with "%0D%0A".
Implementations MAY add a final line break to the body of a message even if there is no trailing "%0D%0A" in the body [...]

See also in section 6 the example from the same RFC:

<mailto:[email protected]?body=send%20current-issue%0D%0Asend%20index>

The above mailto body corresponds to:

send current-issue
send index

Saving images in Python at a very high quality

Just to add my results, also using Matplotlib.

.eps made all my text bold and removed transparency. .svg gave me high-resolution pictures that actually looked like my graph.

import matplotlib.pyplot as plt
fig, ax = plt.subplots()
# Do the plot code
fig.savefig('myimage.svg', format='svg', dpi=1200)

I used 1200 dpi because a lot of scientific journals require images in 1200 / 600 / 300 dpi, depending on what the image is of. Convert to desired dpi and format in GIMP or Inkscape.

Obviously the dpi doesn't matter since .svg are vector graphics and have "infinite resolution".

WAMP/XAMPP is responding very slow over localhost

As most of the answers have pointed out, using the IP address 127.0.0.1 over "localhost" will sometimes help the slowness issue - but this isn't really a solution because it does not fix the underlining problem.

What makes this problem hard (and hit-and-miss), is it can be caused by about a dozen different things between the OS, the WAMP configuration, and your Browser.

  1. Remove ::1 localhost from your Windows hosts file, and make sure 127.0.0.1 localhost is present. You want your request to go directly to the listening IPv4 socket.

  2. Disable IPv6 on your system. You are most likely not using it, and it has been known to cause all kinds of issues.

  3. Exclude your Apache and MySQL binary paths, and the Database folder, from your firewall and anti-virus software. They will interfere and slow things down.

  4. Reset your TCP/IP sub-system and reboot: netsh int ip reset c:\resetlog.txt

  5. Make sure your system is not using stale DNS servers: ipconfig /all

  6. Flush Windows DNS cache: ipconfig /flushdns

  7. Clear your Browser's Cache.

A little more in-depth is this guide: WAMP is Running Very Slow

Get the list of stored procedures created and / or modified on a particular date?

SELECT name
FROM sys.objects
WHERE type = 'P'
AND (DATEDIFF(D,modify_date, GETDATE()) < 7
     OR DATEDIFF(D,create_date, GETDATE()) < 7)

What is a None value?

None is just a value that commonly is used to signify 'empty', or 'no value here'. It is a signal object; it only has meaning because the Python documentation says it has that meaning.

There is only one copy of that object in a given Python interpreter session.

If you write a function, and that function doesn't use an explicit return statement, None is returned instead, for example. That way, programming with functions is much simplified; a function always returns something, even if it is only that one None object.

You can test for it explicitly:

if foo is None:
    # foo is set to None

if bar is not None:
    # bar is set to something *other* than None

Another use is to give optional parameters to functions an 'empty' default:

def spam(foo=None):
    if foo is not None:
        # foo was specified, do something clever!

The function spam() has a optional argument; if you call spam() without specifying it, the default value None is given to it, making it easy to detect if the function was called with an argument or not.

Other languages have similar concepts. SQL has NULL; JavaScript has undefined and null, etc.

Note that in Python, variables exist by virtue of being used. You don't need to declare a variable first, so there are no really empty variables in Python. Setting a variable to None is then not the same thing as setting it to a default empty value; None is a value too, albeit one that is often used to signal emptyness. The book you are reading is misleading on that point.

Should I use past or present tense in git commit messages?

It is up to you. Just use the commit message as you wish. But it is easier if you are not switching between times and languages.

And if you develop in a team - it should be discussed and set fixed.

iOS change navigation bar title font and color

Working in swift 3.0 For changing the title color you need to add titleTextAttributes like this

        let textAttributes = [NSForegroundColorAttributeName:UIColor.white]
        self.navigationController.navigationBar.titleTextAttributes = textAttributes

For changing navigationBar background color you can use this
        self.navigationController.navigationBar.barTintColor = UIColor.white

For changing navigationBar back title and back arrow color you can use this
       self.navigationController.navigationBar.tintColor = UIColor.white

How to get the file name from a full path using JavaScript?

var filename = fullPath.replace(/^.*[\\\/]/, '')

This will handle both \ OR / in paths

Pass array to MySQL stored routine

This helps for me to do IN condition Hope this will help you..

CREATE  PROCEDURE `test`(IN Array_String VARCHAR(100))
BEGIN
    SELECT * FROM Table_Name
    WHERE FIND_IN_SET(field_name_to_search, Array_String);

END//;

Calling:

 call test('3,2,1');

How to tell if tensorflow is using gpu acceleration from inside python shell?

The following will also return the name of your GPU devices.

import tensorflow as tf
tf.test.gpu_device_name()

how to overlap two div in css?

See demo here you need to introduce an additiona calss for second div

.overlap{
    top: -30px;
position: relative;
left: 30px;
}

Groovy write to file (newline)

@Comment for ID:14. It's for me rather easier to write:

out.append it

instead of

out.println it

println did on my machine only write the first file of the ArrayList, with append I get the whole List written into the file.

Kindly anyway for the quick-and-dirty-solution.

How to wrap text using CSS?

Try doing this. Works for IE8, FF3.6, Chrome

<body>
  <table>
    <tr>
      <td>
        <div style="word-wrap: break-word; width: 100px">gdfggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggggg</div>
      </td>
    </tr>
  </table>
</body>

How to get the last char of a string in PHP?

You can find last character using php many ways like substr() and mb_substr().

If you’re using multibyte character encodings like UTF-8, use mb_substr instead of substr

Here i can show you both example:

<?php
    echo substr("testers", -1);
    echo mb_substr("testers", -1);
?>

LIVE DEMO

css background image in a different folder from css

you can use this

body{ background-image: url('../img/bg.png'); }


I tried this on my project where I need to set the background image of a div so I used this and it worked!

update to python 3.7 using anaconda

conda create -n py37 -c anaconda anaconda=5.3

seems to be working.

use Lodash to sort array of object by value

You can use lodash sortBy (https://lodash.com/docs/4.17.4#sortBy).

Your code could be like:

const myArray = [  
   {  
      "id":25,
      "name":"Anakin Skywalker",
      "createdAt":"2017-04-12T12:48:55.000Z",
      "updatedAt":"2017-04-12T12:48:55.000Z"
   },
   {  
      "id":1,
      "name":"Luke Skywalker",
      "createdAt":"2017-04-12T11:25:03.000Z",
      "updatedAt":"2017-04-12T11:25:03.000Z"
   }
]

const myOrderedArray = _.sortBy(myArray, o => o.name)

AngularJs: How to set radio button checked based on model

As discussed somewhat in the question comments, this is one way you could do it:

  • When you first retrieve the data, loop through all locations and set storeDefault to the store that is currently the default.
  • In the markup: <input ... ng-model="$parent.storeDefault" value="{{location.id}}">
  • Before you save the data, loop through all the merchant.storeLocations and set isDefault to false except for the store where location.id compares equal to storeDefault.

The above assumes that each location has a field (e.g., id) that holds a unique value.

Note that $parent.storeDefault is used because ng-repeat creates a child scope, and we want to manipulate the storeDefault parameter on the parent scope.

Fiddle.

Take a screenshot via a Python script on Linux

import ImageGrab
img = ImageGrab.grab()
img.save('test.jpg','JPEG')

this requires Python Imaging Library

I'm getting the "missing a using directive or assembly reference" and no clue what's going wrong

The following technique worked for me:

1) Right click on the project Solution -> Click on Clean solution

2) Right click on the project Solution -> Click on Rebuild solution

In Laravel, the best way to pass different types of flash messages in the session

Another solution would be to create a helper class How to Create helper classes here

class Helper{
     public static function format_message($message,$type)
    {
         return '<p class="alert alert-'.$type.'">'.$message.'</p>'
    }
}

Then you can do this.

Redirect::to('users/login')->with('message', Helper::format_message('A bla blah occured','error'));

or

Redirect::to('users/login')->with('message', Helper::format_message('Thanks for registering!','info'));

and in your view

@if(Session::has('message'))
    {{Session::get('message')}}
@endif

Postgres where clause compare timestamp

Assuming you actually mean timestamp because there is no datetime in Postgres

Cast the timestamp column to a date, that will remove the time part:

select *
from the_table
where the_timestamp_column::date = date '2015-07-15';

This will return all rows from July, 15th.

Note that the above will not use an index on the_timestamp_column. If performance is critical, you need to either create an index on that expression or use a range condition:

select *
from the_table
where the_timestamp_column >= timestamp '2015-07-15 00:00:00'
  and the_timestamp_column < timestamp '2015-07-16 00:00:00';

MySQL "NOT IN" query

Be carefull NOT IN is not an alias for <> ANY, but for <> ALL!

http://dev.mysql.com/doc/refman/5.0/en/any-in-some-subqueries.html

SELECT c FROM t1 LEFT JOIN t2 USING (c) WHERE t2.c IS NULL

cant' be replaced by

SELECT c FROM t1 WHERE c NOT IN (SELECT c FROM t2)

You must use

SELECT c FROM t1 WHERE c <> ANY (SELECT c FROM t2)

How to compile LEX/YACC files on Windows?

What you (probably want) are Flex 2.5.4 (some people are now "maintaining" it and producing newer versions, but IMO they've done more to screw it up than fix any real shortcomings) and byacc 1.9 (likewise). (Edit 2017-11-17: Flex 2.5.4 is not available on Sourceforge any more, and the Flex github repository only goes back to 2.5.5. But you can apparently still get it from a Gnu ftp server at ftp://ftp.gnu.org/old-gnu/gnu-0.2/src/flex-2.5.4.tar.gz.)

Since it'll inevitably be recommended, I'll warn against using Bison. Bison was originally written by Robert Corbett, the same guy who later wrote Byacc, and he openly states that at the time he didn't really know or understand what he was doing. Unfortunately, being young and foolish, he released it under the GPL and now the GPL fans push it as the answer to life's ills even though its own author basically says it should be thought of as essentially a beta test product -- but by the convoluted reasoning of GPL fans, byacc's license doesn't have enough restrictions to qualify as "free"!

Excel function to get first word from sentence in other cell

If you want to cater to 1-word cell, use this... based upon astander's

=IFERROR(LEFT(A1,SEARCH(" ",A1)-1),A1)

Simple Digit Recognition OCR in OpenCV-Python

OCR which stands for Optical Character Recognition is a computer vision technique used to identify the different types of handwritten digits that are used in common mathematics. To perform OCR in OpenCV we will use the KNN algorithm which detects the nearest k neighbors of a particular data point and then classifies that data point based on the class type detected for n neighbors.

Data Used


This data contains 5000 handwritten digits where there are 500 digits for every type of digit. Each digit is of 20×20 pixel dimensions. We will split the data such that 250 digits are for training and 250 digits are for testing for every class.

Below is the implementation.




import numpy as np
import cv2
   
      
# Read the image
image = cv2.imread('digits.png')
  
# gray scale conversion
gray_img = cv2.cvtColor(image,
                        cv2.COLOR_BGR2GRAY)
  
# We will divide the image
# into 5000 small dimensions 
# of size 20x20
divisions = list(np.hsplit(i,100) for i in np.vsplit(gray_img,50))
  
# Convert into Numpy array
# of size (50,100,20,20)
NP_array = np.array(divisions)
   
# Preparing train_data
# and test_data.
# Size will be (2500,20x20)
train_data = NP_array[:,:50].reshape(-1,400).astype(np.float32)
  
# Size will be (2500,20x20)
test_data = NP_array[:,50:100].reshape(-1,400).astype(np.float32)
  
# Create 10 different labels 
# for each type of digit
k = np.arange(10)
train_labels = np.repeat(k,250)[:,np.newaxis]
test_labels = np.repeat(k,250)[:,np.newaxis]
   
# Initiate kNN classifier
knn = cv2.ml.KNearest_create()
  
# perform training of data
knn.train(train_data,
          cv2.ml.ROW_SAMPLE, 
          train_labels)
   
# obtain the output from the
# classifier by specifying the
# number of neighbors.
ret, output ,neighbours,
distance = knn.findNearest(test_data, k = 3)
   
# Check the performance and
# accuracy of the classifier.
# Compare the output with test_labels
# to find out how many are wrong.
matched = output==test_labels
correct_OP = np.count_nonzero(matched)
   
#Calculate the accuracy.
accuracy = (correct_OP*100.0)/(output.size)
   
# Display accuracy.
print(accuracy)


Output

91.64


Well, I decided to workout myself on my question to solve the above problem. What I wanted is to implement a simple OCR using KNearest or SVM features in OpenCV. And below is what I did and how. (it is just for learning how to use KNearest for simple OCR purposes).

1) My first question was about letter_recognition.data file that comes with OpenCV samples. I wanted to know what is inside that file.

It contains a letter, along with 16 features of that letter.

And this SOF helped me to find it. These 16 features are explained in the paper Letter Recognition Using Holland-Style Adaptive Classifiers. (Although I didn't understand some of the features at the end)

2) Since I knew, without understanding all those features, it is difficult to do that method. I tried some other papers, but all were a little difficult for a beginner.

So I just decided to take all the pixel values as my features. (I was not worried about accuracy or performance, I just wanted it to work, at least with the least accuracy)

I took the below image for my training data:

enter image description here

(I know the amount of training data is less. But, since all letters are of the same font and size, I decided to try on this).

To prepare the data for training, I made a small code in OpenCV. It does the following things:

  1. It loads the image.
  2. Selects the digits (obviously by contour finding and applying constraints on area and height of letters to avoid false detections).
  3. Draws the bounding rectangle around one letter and wait for key press manually. This time we press the digit key ourselves corresponding to the letter in the box.
  4. Once the corresponding digit key is pressed, it resizes this box to 10x10 and saves all 100 pixel values in an array (here, samples) and corresponding manually entered digit in another array(here, responses).
  5. Then save both the arrays in separate .txt files.

At the end of the manual classification of digits, all the digits in the training data (train.png) are labeled manually by ourselves, image will look like below:

enter image description here

Below is the code I used for the above purpose (of course, not so clean):

import sys

import numpy as np
import cv2

im = cv2.imread('pitrain.png')
im3 = im.copy()

gray = cv2.cvtColor(im,cv2.COLOR_BGR2GRAY)
blur = cv2.GaussianBlur(gray,(5,5),0)
thresh = cv2.adaptiveThreshold(blur,255,1,1,11,2)

#################      Now finding Contours         ###################

contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)

samples =  np.empty((0,100))
responses = []
keys = [i for i in range(48,58)]

for cnt in contours:
    if cv2.contourArea(cnt)>50:
        [x,y,w,h] = cv2.boundingRect(cnt)
        
        if  h>28:
            cv2.rectangle(im,(x,y),(x+w,y+h),(0,0,255),2)
            roi = thresh[y:y+h,x:x+w]
            roismall = cv2.resize(roi,(10,10))
            cv2.imshow('norm',im)
            key = cv2.waitKey(0)

            if key == 27:  # (escape to quit)
                sys.exit()
            elif key in keys:
                responses.append(int(chr(key)))
                sample = roismall.reshape((1,100))
                samples = np.append(samples,sample,0)

responses = np.array(responses,np.float32)
responses = responses.reshape((responses.size,1))
print "training complete"

np.savetxt('generalsamples.data',samples)
np.savetxt('generalresponses.data',responses)

Now we enter in to training and testing part.

For the testing part, I used the below image, which has the same type of letters I used for the training phase.

enter image description here

For training we do as follows:

  1. Load the .txt files we already saved earlier
  2. create an instance of the classifier we are using (it is KNearest in this case)
  3. Then we use KNearest.train function to train the data

For testing purposes, we do as follows:

  1. We load the image used for testing
  2. process the image as earlier and extract each digit using contour methods
  3. Draw a bounding box for it, then resize it to 10x10, and store its pixel values in an array as done earlier.
  4. Then we use KNearest.find_nearest() function to find the nearest item to the one we gave. ( If lucky, it recognizes the correct digit.)

I included last two steps (training and testing) in single code below:

import cv2
import numpy as np

#######   training part    ############### 
samples = np.loadtxt('generalsamples.data',np.float32)
responses = np.loadtxt('generalresponses.data',np.float32)
responses = responses.reshape((responses.size,1))

model = cv2.KNearest()
model.train(samples,responses)

############################# testing part  #########################

im = cv2.imread('pi.png')
out = np.zeros(im.shape,np.uint8)
gray = cv2.cvtColor(im,cv2.COLOR_BGR2GRAY)
thresh = cv2.adaptiveThreshold(gray,255,1,1,11,2)

contours,hierarchy = cv2.findContours(thresh,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)

for cnt in contours:
    if cv2.contourArea(cnt)>50:
        [x,y,w,h] = cv2.boundingRect(cnt)
        if  h>28:
            cv2.rectangle(im,(x,y),(x+w,y+h),(0,255,0),2)
            roi = thresh[y:y+h,x:x+w]
            roismall = cv2.resize(roi,(10,10))
            roismall = roismall.reshape((1,100))
            roismall = np.float32(roismall)
            retval, results, neigh_resp, dists = model.find_nearest(roismall, k = 1)
            string = str(int((results[0][0])))
            cv2.putText(out,string,(x,y+h),0,1,(0,255,0))

cv2.imshow('im',im)
cv2.imshow('out',out)
cv2.waitKey(0)

And it worked, below is the result I got:

enter image description here


Here it worked with 100% accuracy. I assume this is because all the digits are of the same kind and the same size.

But anyway, this is a good start to go for beginners (I hope so).

How to hide the soft keyboard from inside a fragment?

This worked for me in Kotlin class

fun hideKeyboard(activity: Activity) {
    try {
        val inputManager = activity
            .getSystemService(Context.INPUT_METHOD_SERVICE) as InputMethodManager
        val currentFocusedView = activity.currentFocus
        if (currentFocusedView != null) {
            inputManager.hideSoftInputFromWindow(currentFocusedView.windowToken, InputMethodManager.HIDE_NOT_ALWAYS)
        }
    } catch (e: Exception) {
        e.printStackTrace()
    }

}

JWT refresh token flow

Assuming that this is about OAuth 2.0 since it is about JWTs and refresh tokens...:

  1. just like an access token, in principle a refresh token can be anything including all of the options you describe; a JWT could be used when the Authorization Server wants to be stateless or wants to enforce some sort of "proof-of-possession" semantics on to the client presenting it; note that a refresh token differs from an access token in that it is not presented to a Resource Server but only to the Authorization Server that issued it in the first place, so the self-contained validation optimization for JWTs-as-access-tokens does not hold for refresh tokens

  2. that depends on the security/access of the database; if the database can be accessed by other parties/servers/applications/users, then yes (but your mileage may vary with where and how you store the encryption key...)

  3. an Authorization Server may issue both access tokens and refresh tokens at the same time, depending on the grant that is used by the client to obtain them; the spec contains the details and options on each of the standardized grants

XAMPP keeps showing Dashboard/Welcome Page instead of the Configuration Page

I've resolved the issue, by going to setting and permalink, just choose post-name.

it should work and you'll see the exact page.. rather than dashboard/xampp page again

Best of Luck

How do I check that a Java String is not all whitespaces?

Just an performance comparement on openjdk 13, Windows 10. For each of theese texts:

"abcd"
"    "
" \r\n\t"
" ab "
" \n\n\r\t   \n\r\t\t\t   \r\n\r\n\r\t \t\t\t\r\n\n"
"lorem ipsum dolor sit amet  consectetur adipisici elit"
"1234657891234567891324569871234567891326987132654798"

executed one of following tests:

// trim + empty
input.trim().isEmpty()

// simple match
input.matches("\\S")

// match with precompiled pattern
final Pattern PATTERN = Pattern.compile("\\S");
PATTERN.matcher(input).matches()

// java 11's isBlank
input.isBlank()

each 10.000.000 times.

The results:

METHOD    min   max   note
trim:      18   313   much slower if text not trimmed
match:   1799  2010   
pattern:  571   662   
isBlank:   60   338   faster the earlier hits the first non-whitespace character

Quite surprisingly the trim+empty is the fastest. Even if it needs to construct the trimmed text. Still faster then simple for-loop looking for one single non-whitespaced character...

EDIT: The longer text, the more numbers differs. Trim of long text takes longer time than just simple loop. However, the regexs are still the slowest solution.

SQL to Entity Framework Count Group-By

Query syntax

var query = from p in context.People
            group p by p.name into g
            select new
            {
              name = g.Key,
              count = g.Count()
            };

Method syntax

var query = context.People
                   .GroupBy(p => p.name)
                   .Select(g => new { name = g.Key, count = g.Count() });

Storing and Retrieving ArrayList values from hashmap

for (Map.Entry<String, ArrayList<Integer>> entry : map.entrySet()) {
 System.out.println( entry.getKey());     
 System.out.println( entry.getValue());//Returns the list of values
}

Python class input argument

You just need to do it in correct syntax. Let me give you a minimal example I just did with Python interactive shell:

>>> class MyNameClass():
...   def __init__(self, myname):
...       print myname
... 
>>> p1 = MyNameClass('John')
John

Java Wait and Notify: IllegalMonitorStateException

You're calling both wait and notifyAll without using a synchronized block. In both cases the calling thread must own the lock on the monitor you call the method on.

From the docs for notify (wait and notifyAll have similar documentation but refer to notify for the fullest description):

This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:

  • By executing a synchronized instance method of that object.
  • By executing the body of a synchronized statement that synchronizes on the object.
  • For objects of type Class, by executing a synchronized static method of that class.

Only one thread at a time can own an object's monitor.

Only one thread will be able to actually exit wait at a time after notifyAll as they'll all have to acquire the same monitor again - but all will have been notified, so as soon as the first one then exits the synchronized block, the next will acquire the lock etc.

Where is Java Installed on Mac OS X?

For :

  • OS X : 10.11.6

  • Java : 8

I confirm the answer of @Morrie .

   export JAVA_HOME=/Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin/Contents/Home;

But if you are running containers your life will be easier

Range of values in C Int and Long 32 - 64 bits

Take a look at limits.h. You can find the specific values for your compiler. INT_MIN and INT_MAX will be of interest.

C# : Out of Memory exception

3 years old topic, but I found another working solution. If you're sure you have enough free memory, running 64 bit OS and still getting exceptions, go to Project properties -> Build tab and be sure to set x64 as a Platform target.

enter image description here

How to show Bootstrap table with sort icon

BOOTSTRAP 4

you can use a combination of

  • fa-chevron-down, fa-chevron-up

  • fa-sort-down, fa-sort-up

<th class="text-center">
    <div class="btn-group" role="group">
        <button type="button" class="btn btn-xs btn-link py-0 pl-0 pr-1">
             Some Text OR icon
        </button>
        <div class="btn-group-vertical">
            <a href="?sort=asc" class="btn btn-xs btn-link p-0">
                <i class="fas fa-sort-up"></i>
            </a>
            <a href="?sort=desc" class="btn btn-xs btn-link p-0">
                <i class="fas fa-sort-down"></i>
            </a>
        </div>
    </div>
</th>

How to delete an app from iTunesConnect / App Store Connect

I had the same problem with a dummy app that happened to have the same name as my final app and couldn't publish because the App Name is already in use

To fix it, instead of deleting it(which you can't) I just changed the name of the dummy app to something random and hit SAVE. Then I was able to add the new app with the proper name

How to get response body using HttpURLConnection, when code other than 2xx is returned?

Wrong method was used for errors, here is the working code:

BufferedReader br = null;
if (100 <= conn.getResponseCode() && conn.getResponseCode() <= 399) {
    br = new BufferedReader(new InputStreamReader(conn.getInputStream()));
} else {
    br = new BufferedReader(new InputStreamReader(conn.getErrorStream()));
}

"NoClassDefFoundError: Could not initialize class" error

NoClassDefFound error is a nebulous error and is often hiding a more serious issue. It is not the same as ClassNotFoundException (which is thrown when the class is just plain not there).

NoClassDefFound may indicate the class is not there, as the javadocs indicate, but it is typically thrown when, after the classloader has loaded the bytes for the class and calls "defineClass" on them. Also carefully check your full stack trace for other clues or possible "cause" Exceptions (though your particular backtrace shows none).

The first place to look when you get a NoClassDefFoundError is in the static bits of your class i.e. any initialization that takes place during the defining of the class. If this fails it will throw a NoClassDefFoundError - it's supposed to throw an ExceptionInInitializerError and indicate the details of the problem but in my experience, these are rare. It will only do the ExceptionInInitializerError the first time it tries to define the class, after that it will just throw NoClassDefFound. So look at earlier logs.

I would thus suggest looking at the code in that HibernateTransactionInterceptor line and seeing what it is requiring. It seems that it is unable to define the class SpringFactory. So maybe check the initialization code in that class, that might help. If you can debug it, stop it at the last line above (17) and debug into so you can try find the exact line that is causing the exception. Also check higher up in the log, if you very lucky there might be an ExceptionInInitializerError.

CodeIgniter htaccess and URL rewrite issues

Just add this in the .htaccess file:

DirectoryIndex index.php
RewriteEngine on
RewriteCond $1 !^(index\.php|images|css|js|robots\.txt|favicon\.ico)
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ ./index.php?/$1 [L,QSA]

Eclipse "Invalid Project Description" when creating new project from existing source

The easiest way to solve this problem is just to move your`s project to another folder and import it. This is because you have already had this project(or project with the same name) in that folder. And when you delete project, eclipse still retains a reference to it

How do I set the driver's python version in spark?

Ran into this today at work. An admin thought it prudent to hard code Python 2.7 as the PYSPARK_PYTHON and PYSPARK_DRIVER_PYTHON in $SPARK_HOME/conf/spark-env.sh. Needless to say this broke all of our jobs that utilize any other python versions or environments (which is > 90% of our jobs). @PhillipStich points out correctly that you may not always have write permissions for this file, as is our case. While setting the configuration in the spark-submit call is an option, another alternative (when running in yarn/cluster mode) is to set the SPARK_CONF_DIR environment variable to point to another configuration script. There you could set your PYSPARK_PYTHON and any other options you may need. A template can be found in the spark-env.sh source code on github.

How to set the maxAllowedContentLength to 500MB while running on IIS7?

According to MSDN maxAllowedContentLength has type uint, its maximum value is 4,294,967,295 bytes = 3,99 gb

So it should work fine.

See also Request Limits article. Does IIS return one of these errors when the appropriate section is not configured at all?

See also: Maximum request length exceeded

PostgreSQL function for last inserted ID

I had this issue with Java and Postgres. I fixed it by updating a new Connector-J version.

postgresql-9.2-1002.jdbc4.jar

https://jdbc.postgresql.org/download.html: Version 42.2.12

https://jdbc.postgresql.org/download/postgresql-42.2.12.jar

How can I upload fresh code at github?

It seems like Github has changed their layout since you posted this question. I just created a repository and it used to give you instructions on screen. It appears they have changed that approach.

Here is the information they used to give on repo creation:

Create A Repo · GitHub Help

Select N random elements from a List<T> in C#

Using linq:

YourList.OrderBy(x => rnd.Next()).Take(5)

How do I send an HTML email?

You can find a complete and very simple java class for sending emails using Google(gmail) account here, Send email message using java application

It uses following properties

Properties props = new Properties();
  props.put("mail.smtp.auth", "true");
  props.put("mail.smtp.starttls.enable", "true");
  props.put("mail.smtp.host", "smtp.gmail.com");
  props.put("mail.smtp.port", "587");

NSURLConnection Using iOS Swift

Check Below Codes :

1. SynchronousRequest

Swift 1.2

    let urlPath: String = "YOUR_URL_HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request1: NSURLRequest = NSURLRequest(URL: url)
    var response: AutoreleasingUnsafeMutablePointer<NSURLResponse?>=nil
    var dataVal: NSData =  NSURLConnection.sendSynchronousRequest(request1, returningResponse: response, error:nil)!
    var err: NSError
    println(response)
    var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataVal, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary
    println("Synchronous\(jsonResult)")

Swift 2.0 +

let urlPath: String = "YOUR_URL_HERE"
    let url: NSURL = NSURL(string: urlPath)!
    let request1: NSURLRequest = NSURLRequest(URL: url)
    let response: AutoreleasingUnsafeMutablePointer<NSURLResponse?>=nil


    do{

        let dataVal = try NSURLConnection.sendSynchronousRequest(request1, returningResponse: response)

            print(response)
            do {
                if let jsonResult = try NSJSONSerialization.JSONObjectWithData(dataVal, options: []) as? NSDictionary {
                    print("Synchronous\(jsonResult)")
                }
            } catch let error as NSError {
                print(error.localizedDescription)
            }



    }catch let error as NSError
    {
         print(error.localizedDescription)
    }

2. AsynchonousRequest

Swift 1.2

let urlPath: String = "YOUR_URL_HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request1: NSURLRequest = NSURLRequest(URL: url)
    let queue:NSOperationQueue = NSOperationQueue()
    NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in
        var err: NSError
        var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
        println("Asynchronous\(jsonResult)")
       })

Swift 2.0 +

let urlPath: String = "YOUR_URL_HERE"
    let url: NSURL = NSURL(string: urlPath)!
    let request1: NSURLRequest = NSURLRequest(URL: url)
    let queue:NSOperationQueue = NSOperationQueue()

    NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in

        do {
            if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
                print("ASynchronous\(jsonResult)")
            }
        } catch let error as NSError {
            print(error.localizedDescription)
        }


    })

3. As usual URL connection

Swift 1.2

    var dataVal = NSMutableData()
    let urlPath: String = "YOUR URL HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request: NSURLRequest = NSURLRequest(URL: url)
    var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!
    connection.start()

Then

 func connection(connection: NSURLConnection!, didReceiveData data: NSData!){
    self.dataVal?.appendData(data)
}


func connectionDidFinishLoading(connection: NSURLConnection!)
{
    var error: NSErrorPointer=nil

    var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataVal!, options: NSJSONReadingOptions.MutableContainers, error: error) as NSDictionary

    println(jsonResult)



}

Swift 2.0 +

   var dataVal = NSMutableData()
    let urlPath: String = "YOUR URL HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request: NSURLRequest = NSURLRequest(URL: url)
    var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!
    connection.start()

Then

func connection(connection: NSURLConnection!, didReceiveData data: NSData!){
    dataVal.appendData(data)
}


func connectionDidFinishLoading(connection: NSURLConnection!)
{

    do {
        if let jsonResult = try NSJSONSerialization.JSONObjectWithData(dataVal, options: []) as? NSDictionary {
            print(jsonResult)
        }
    } catch let error as NSError {
        print(error.localizedDescription)
    }

}

4. Asynchronous POST Request

Swift 1.2

    let urlPath: String = "YOUR URL HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)

    request1.HTTPMethod = "POST"
     var stringPost="deviceToken=123456" // Key and Value

    let data = stringPost.dataUsingEncoding(NSUTF8StringEncoding)

    request1.timeoutInterval = 60
    request1.HTTPBody=data
    request1.HTTPShouldHandleCookies=false

    let queue:NSOperationQueue = NSOperationQueue()

     NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in


        var err: NSError

        var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
        println("AsSynchronous\(jsonResult)")


        })

Swift 2.0 +

let urlPath: String = "YOUR URL HERE"
    let url: NSURL = NSURL(string: urlPath)!
    let request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)

    request1.HTTPMethod = "POST"
    let stringPost="deviceToken=123456" // Key and Value

    let data = stringPost.dataUsingEncoding(NSUTF8StringEncoding)

    request1.timeoutInterval = 60
    request1.HTTPBody=data
    request1.HTTPShouldHandleCookies=false

    let queue:NSOperationQueue = NSOperationQueue()

    NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in

        do {
            if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
                print("ASynchronous\(jsonResult)")
            }
        } catch let error as NSError {
            print(error.localizedDescription)
        }


    })

5. Asynchronous GET Request

Swift 1.2

    let urlPath: String = "YOUR URL HERE"
    var url: NSURL = NSURL(string: urlPath)!
    var request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)

    request1.HTTPMethod = "GET"
    request1.timeoutInterval = 60
    let queue:NSOperationQueue = NSOperationQueue()

     NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse!, data: NSData!, error: NSError!) -> Void in


        var err: NSError

        var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary
        println("AsSynchronous\(jsonResult)")


        })

Swift 2.0 +

let urlPath: String = "YOUR URL HERE"
    let url: NSURL = NSURL(string: urlPath)!
    let request1: NSMutableURLRequest = NSMutableURLRequest(URL: url)

    request1.HTTPMethod = "GET"
    let queue:NSOperationQueue = NSOperationQueue()

    NSURLConnection.sendAsynchronousRequest(request1, queue: queue, completionHandler:{ (response: NSURLResponse?, data: NSData?, error: NSError?) -> Void in

        do {
            if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
                print("ASynchronous\(jsonResult)")
            }
        } catch let error as NSError {
            print(error.localizedDescription)
        }


    })

6. Image(File) Upload

Swift 2.0 +

  let mainURL = "YOUR_URL_HERE"

    let url = NSURL(string: mainURL)
    let request = NSMutableURLRequest(URL: url!)
    let boundary = "78876565564454554547676"
    request.addValue("multipart/form-data; boundary=\(boundary)", forHTTPHeaderField: "Content-Type")


    request.HTTPMethod = "POST" // POST OR PUT What you want
    let session = NSURLSession(configuration:NSURLSessionConfiguration.defaultSessionConfiguration(), delegate: nil, delegateQueue: nil)

    let imageData = UIImageJPEGRepresentation(UIImage(named: "Test.jpeg")!, 1)





    var body = NSMutableData()

    body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)

    // Append your parameters

    body.appendData("Content-Disposition: form-data; name=\"name\"\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
    body.appendData("PREMKUMAR\r\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
    body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)

    body.appendData("Content-Disposition: form-data; name=\"description\"\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
    body.appendData("IOS_DEVELOPER\r\n".dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: true)!)
    body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)


    // Append your Image/File Data

    var imageNameval = "HELLO.jpg"

    body.appendData("--\(boundary)\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
    body.appendData("Content-Disposition: form-data; name=\"profile_photo\"; filename=\"\(imageNameval)\"\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
    body.appendData("Content-Type: image/jpeg\r\n\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)
    body.appendData(imageData!)
    body.appendData("\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)

    body.appendData("--\(boundary)--\r\n".dataUsingEncoding(NSUTF8StringEncoding)!)

    request.HTTPBody = body




    let dataTask = session.dataTaskWithRequest(request) { (data, response, error) -> Void in

        if error != nil {

            //handle error


        }
        else {




            let outputString : NSString = NSString(data:data!, encoding:NSUTF8StringEncoding)!
            print("Response:\(outputString)")


        }
    }
    dataTask.resume()

7. GET,POST,Etc Swift 3.0 +

let request = NSMutableURLRequest(url: URL(string: "YOUR_URL_HERE" ,param: param))!,
    cachePolicy: .useProtocolCachePolicy,
    timeoutInterval:60)
request.httpMethod = "POST" // POST ,GET, PUT What you want 

let session = URLSession.shared



  let dataTask = session.dataTask(with: request as URLRequest) {data,response,error in

do {
            if let jsonResult = try NSJSONSerialization.JSONObjectWithData(data!, options: []) as? NSDictionary {
                print("ASynchronous\(jsonResult)")
            }
        } catch let error as NSError {
            print(error.localizedDescription)
        }

    }
    dataTask.resume()

JQuery wait for page to finish loading before starting the slideshow?

The $(document).ready mechanism is meant to fire after the DOM has been loaded successfully but makes no guarantees as to the state of the images referenced by the page.

When in doubt, fall back on the good ol' window.onload event:

window.onload = function()
{
  //your code here
};

Now, this is obviously slower than the jQuery approach. However, you can compromise somewhere in between:

$(document).ready
(
  function()
  {
    var img = document.getElementById("myImage");

    var intervalId = setInterval(
                        function()
                        {
                          if(img.complete)
                          {
                            clearInterval(intervalId);
                            //now we can start rotating the header
                          }
                        },
                        50);
  }
);

To explain a bit:

  1. we grab the DOM element of the image whose image we want completely loaded

  2. we then set an interval to fire every 50 milliseconds.

  3. if, during one of these intervals, the complete attribute of this image is set to true, the interval is cleared and the rotate operation is safe to start.

Reading *.wav files in Python

PyDub (http://pydub.com/) has not been mentioned and that should be fixed. IMO this is the most comprehensive library for reading audio files in Python right now, although not without its faults. Reading a wav file:

from pydub import AudioSegment

audio_file = AudioSegment.from_wav('path_to.wav')
# or
audio_file = AudioSegment.from_file('path_to.wav')

# do whatever you want with the audio, change bitrate, export, convert, read info, etc.
# Check out the API docs http://pydub.com/

PS. The example is about reading a wav file, but PyDub can handle a lot of various formats out of the box. The caveat is that it's based on both native Python wav support and ffmpeg, so you have to have ffmpeg installed and a lot of the pydub capabilities rely on the ffmpeg version. Usually if ffmpeg can do it, so can pydub (which is quite powerful).

Non-disclaimer: I'm not related to the project, but I am a heavy user.

What port is a given program using?

most decent firewall programs should allow you to access this information. I know that Agnitum OutpostPro Firewall does.

How do I drop a foreign key in SQL Server?

Try

alter table company drop constraint Company_CountryID_FK


alter table company drop column CountryID

Hide/encrypt password in bash file to stop accidentally seeing it

Following line in above code is not working

DB_PASSWORD=$(eval echo ${DB_PASSWORD} | base64 --decode)

Correct line is:

DB_PASSWORD=`echo $PASSWORD|base64 -d`

And save the password in other file as PASSWORD.

Bash scripting, multiple conditions in while loop

The correct options are (in increasing order of recommendation):

# Single POSIX test command with -o operator (not recommended anymore).
# Quotes strongly recommended to guard against empty or undefined variables.
while [ "$stats" -gt 300 -o "$stats" -eq 0 ]

# Two POSIX test commands joined in a list with ||.
# Quotes strongly recommended to guard against empty or undefined variables.
while [ "$stats" -gt 300 ] || [ "$stats" -eq 0 ]

# Two bash conditional expressions joined in a list with ||.
while [[ $stats -gt 300 ]] || [[ $stats -eq 0 ]]

# A single bash conditional expression with the || operator.
while [[ $stats -gt 300 || $stats -eq 0 ]]

# Two bash arithmetic expressions joined in a list with ||.
# $ optional, as a string can only be interpreted as a variable
while (( stats > 300 )) || (( stats == 0 ))

# And finally, a single bash arithmetic expression with the || operator.
# $ optional, as a string can only be interpreted as a variable
while (( stats > 300 || stats == 0 ))

Some notes:

  1. Quoting the parameter expansions inside [[ ... ]] and ((...)) is optional; if the variable is not set, -gt and -eq will assume a value of 0.

  2. Using $ is optional inside (( ... )), but using it can help avoid unintentional errors. If stats isn't set, then (( stats > 300 )) will assume stats == 0, but (( $stats > 300 )) will produce a syntax error.

Add one year in current date PYTHON

convert it into python datetime object if it isn't already. then add deltatime

one_years_later = Your_date + datetime.timedelta(days=(years*days_per_year)) 

for your case days=365.

you can have condition to check if the year is leap or no and adjust days accordingly

you can add as many years as you want

Chrome Uncaught Syntax Error: Unexpected Token ILLEGAL

There's some sort of bogus character at the end of that source. Try deleting the last line and adding it back.

I can't figure out exactly what's there, yet ...

edit — I think it's a zero-width space, Unicode 200B. Seems pretty weird and I can't be sure of course that it's not a Stackoverflow artifact, but when I copy/paste that last function including the complete last line into the Chrome console, I get your error.

A notorious source of such characters are websites like jsfiddle. I'm not saying that there's anything wrong with them — it's just a side-effect of something, maybe the use of content-editable input widgets.

If you suspect you've got a case of this ailment, and you're on MacOS or Linux/Unix, the od command line tool can show you (albeit in a fairly ugly way) the numeric values in the characters of the source code file. Some IDEs and editors can show "funny" characters as well. Note that such characters aren't always a problem. It's perfectly OK (in most reasonable programming languages, anyway) for there to be embedded Unicode characters in string constants, for example. The problems start happening when the language parser encounters the characters when it doesn't expect them.

PHP Date Time Current Time Add Minutes

$time = strtotime(date('2016-02-03 12:00:00'));
        echo date("H:i:s",strtotime("-30 minutes", $time));

Detect when an HTML5 video finishes

You can add an event listener with 'ended' as first param

Like this :

<video src="video.ogv" id="myVideo">
  video not supported
</video>

<script type='text/javascript'>
    document.getElementById('myVideo').addEventListener('ended',myHandler,false);
    function myHandler(e) {
        // What you want to do after the event
    }
</script>

How can I fix WebStorm warning "Unresolved function or method" for "require" (Firefox Add-on SDK)

Disable JetBrains Inspections and get the ESLint plugin.

The only thing that File | Invalidate caches and restart does for me is reset it long enough to trick me into thinking the error is gone. Once the inspections run again the error comes back like a gift that keeps on giving.

I saved myself all that frustration by disabling all JetBrains inspections (Editor > Inspections > uncheck JavaScript) Then I installed the ESLint plugin.

The inspection that causes "Unresolved function method" can be turned off by going to JetBrains inspections (Editor > Inspections > JavaScript) and searching for "Unresolved Javascript" and turning off "Unresolved Javascript function" and "Unresolved Javascript variable"

I killed them all and have edited my code hassle free ever since.

Regex: match word that ends with "Id"

How about \A[a-z]*Id\z? [This makes characters before Id optional. Use \A[a-z]+Id\z if there needs to be one or more characters preceding Id.]

How can I store the result of a system command in a Perl variable?

Use backticks for system commands, which helps to store their results into Perl variables.

my $pid = 5892;
my $not = ``top -H -p $pid -n 1 | grep myprocess | wc -l`; 
print "not = $not\n";

Extracting just Month and Year separately from Pandas Datetime column

df['year_month']=df.datetime_column.apply(lambda x: str(x)[:7])

This worked fine for me, didn't think pandas would interpret the resultant string date as date, but when i did the plot, it knew very well my agenda and the string year_month where ordered properly... gotta love pandas!

Android webview slow

Try this:

mWebView.setLayerType(View.LAYER_TYPE_HARDWARE, null);

Hide all elements with class using plain Javascript

There are many ways to hide all elements which has certain class in javascript one way is to using for loop but here i want to show you other ways to doing it.

1.forEach and querySelectorAll('.classname')

document.querySelectorAll('.classname').forEach(function(el) {
   el.style.display = 'none';
});

2.for...of with getElementsByClassName

for (let element of document.getElementsByClassName("classname")){
   element.style.display="none";
}

3.Array.protoype.forEach getElementsByClassName

Array.prototype.forEach.call(document.getElementsByClassName("classname"), function(el) {
    // Do something amazing below
    el.style.display = 'none';
});

4.[ ].forEach and getElementsByClassName

[].forEach.call(document.getElementsByClassName("classname"), function (el) {
    el.style.display = 'none';
});

i have shown some of the possible ways, there are also more ways to do it, but from above list you can Pick whichever suits and easy for you.

Note: all above methods are supported in modern browsers but may be some of them will not work in old age browsers like internet explorer.

Adding List<t>.add() another list

List<T>.Add adds a single element. Instead, use List<T>.AddRange to add multiple values.

Additionally, List<T>.AddRange takes an IEnumerable<T>, so you don't need to convert tripDetails into a List<TripDetails>, you can pass it directly, e.g.:

tripDetailsCollection.AddRange(tripDetails);

How to solve "java.io.IOException: error=12, Cannot allocate memory" calling Runtime#exec()?

This is the solution but you have to set:

echo 1 > /proc/sys/vm/overcommit_memory

How to do a SQL NOT NULL with a DateTime?

erm it does work? I've just tested it?

/****** Object:  Table [dbo].[DateTest]    Script Date: 09/26/2008 10:44:21 ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE TABLE [dbo].[DateTest](
    [Date1] [datetime] NULL,
    [Date2] [datetime] NOT NULL
) ON [PRIMARY]

GO
Insert into DateTest (Date1,Date2) VALUES (NULL,'1-Jan-2008')
Insert into DateTest (Date1,Date2) VALUES ('1-Jan-2008','1-Jan-2008')
Go
SELECT * FROM DateTest WHERE Date1 is not NULL
GO
SELECT * FROM DateTest WHERE Date2 is not NULL

Create hive table using "as select" or "like" and also specify delimiter

Both the answers provided above work fine.

  1. CREATE TABLE person AS select * from employee;
  2. CREATE TABLE person LIKE employee;

FormsAuthentication.SignOut() does not log the user out

Using two of the above postings by x64igor and Phil Haselden solved this:

1. x64igor gave the example to do the Logout:

  • You first need to Clear the Authentication Cookie and Session Cookie by passing back empty cookies in the Response to the Logout.

    public ActionResult LogOff()
    {
        FormsAuthentication.SignOut();
        Session.Clear();  // This may not be needed -- but can't hurt
        Session.Abandon();
    
        // Clear authentication cookie
        HttpCookie rFormsCookie = new HttpCookie( FormsAuthentication.FormsCookieName, "" );
        rFormsCookie.Expires = DateTime.Now.AddYears( -1 );
        Response.Cookies.Add( rFormsCookie );
    
        // Clear session cookie 
        HttpCookie rSessionCookie = new HttpCookie( "ASP.NET_SessionId", "" );
        rSessionCookie.Expires = DateTime.Now.AddYears( -1 );
        Response.Cookies.Add( rSessionCookie );
    

2. Phil Haselden gave the example above of how to prevent caching after logout:

  • You need to Invalidate the Cache on the Client Side via the Response.

        // Invalidate the Cache on the Client Side
        Response.Cache.SetCacheability( HttpCacheability.NoCache );
        Response.Cache.SetNoStore();
    
        // Redirect to the Home Page (that should be intercepted and redirected to the Login Page first)
        return RedirectToAction( "Index", "Home" ); 
    }
    

Replace None with NaN in pandas dataframe

You can use DataFrame.fillna or Series.fillna which will replace the Python object None, not the string 'None'.

import pandas as pd
import numpy as np

For dataframe:

df = df.fillna(value=np.nan)

For column or series:

df.mycol.fillna(value=np.nan, inplace=True)

Pandas left outer join multiple dataframes on multiple columns

Merge them in two steps, df1 and df2 first, and then the result of that to df3.

In [33]: s1 = pd.merge(df1, df2, how='left', on=['Year', 'Week', 'Colour'])

I dropped year from df3 since you don't need it for the last join.

In [39]: df = pd.merge(s1, df3[['Week', 'Colour', 'Val3']],
                       how='left', on=['Week', 'Colour'])

In [40]: df
Out[40]: 
   Year Week Colour  Val1  Val2 Val3
0  2014    A    Red    50   NaN  NaN
1  2014    B    Red    60   NaN   60
2  2014    B  Black    70   100   10
3  2014    C    Red    10    20  NaN
4  2014    D  Green    20   NaN   20

[5 rows x 6 columns]

ReactJS: Warning: setState(...): Cannot update during an existing state transition

I am giving a generic example for better understanding, In the following code

render(){
    return(
      <div>

        <h3>Simple Counter</h3>
        <Counter
          value={this.props.counter}
          onIncrement={this.props.increment()} <------ calling the function
          onDecrement={this.props.decrement()} <-----------
          onIncrementAsync={this.props.incrementAsync()} />
      </div>
    )
  }

When supplying props I am calling the function directly, this wold have a infinite loop execution and would give you that error, Remove the function call everything works normally.

render(){
    return(
      <div>

        <h3>Simple Counter</h3>
        <Counter
          value={this.props.counter}
          onIncrement={this.props.increment} <------ function call removed
          onDecrement={this.props.decrement} <-----------
          onIncrementAsync={this.props.incrementAsync} />
      </div>
    )
  }

Effective swapping of elements of an array in Java

first of all you shouldn't write for (int k = 0; k **<** data.length **- 1**; k++)because the < is until the k is smaller the length -1 and then the loop will run until the last position in the array and won't get the last place in the array; so you can fix it by two ways: 1: for (int k = 0; k <= data.length - 1; k++) 2: for (int k = 0; k < data.length; k++) and then it will work fine!!! and to swap you can use: to keep one of the int's in another place and then to replace

int x = data[k]
data[k] = data[data.length - 1]
data[data.length - 1] = x;

because you don't want to lose one of the int's!!

How to convert numbers between hexadecimal and decimal

If it's a really big hex string beyond the capacity of the normal integer:

For .NET 3.5, we can use BouncyCastle's BigInteger class:

String hex = "68c7b05d0000000002f8";
// results in "494809724602834812404472"
String decimal = new Org.BouncyCastle.Math.BigInteger(hex, 16).ToString();

.NET 4.0 has the BigInteger class.

How and where to use ::ng-deep?

USAGE

::ng-deep, >>> and /deep/ disable view encapsulation for specific CSS rules, in other words, it gives you access to DOM elements, which are not in your component's HTML. For example, if you're using Angular Material (or any other third-party library like this), some generated elements are outside of your component's area (such as dialog) and you can't access those elements directly or using a regular CSS way. If you want to change the styles of those elements, you can use one of those three things, for example:

::ng-deep .mat-dialog {
  /* styles here */
}

For now Angular team recommends making "deep" manipulations only with EMULATED view encapsulation.

DEPRECATION

"deep" manipulations are actually deprecated too, BUT it stills working for now, because Angular does pre-processing support (don't rush to refuse ::ng-deep today, take a look at deprecation practices first).

Anyway, before following this way, I recommend you to take a look at disabling view encapsulation approach (which is not ideal too, it allows your styles to leak into other components), but in some cases, it's a better way. If you decided to disable view encapsulation, it's strongly recommended to use specific classes to avoid CSS rules intersection, and finally, avoid a mess in your stylesheets. It's really easy to disable right in the component's .ts file:

@Component({
  selector: '',
  template: '',
  styles: [''],
  encapsulation: ViewEncapsulation.None  // Use to disable CSS Encapsulation for this component
})

You can find more info about the view encapsulation in this article.

Controlling Spacing Between Table Cells

Use border-collapse and border-spacing to get spaces between the table cells. I would not recommend using floating cells as suggested by QQping.

JSFiddle

Safely casting long to int in Java

With BigDecimal:

long aLong = ...;
int anInt = new BigDecimal(aLong).intValueExact(); // throws ArithmeticException
                                                   // if outside bounds

Get mouse wheel events in jQuery?

This is working in each IE, Firefox and Chrome's latest versions.

$(document).ready(function(){
        $('#whole').bind('DOMMouseScroll mousewheel', function(e){
            if(e.originalEvent.wheelDelta > 0 || e.originalEvent.detail < 0) {
                alert("up");
            }
            else{
                alert("down");
            }
        });
    });

What are the differences between git branch, fork, fetch, merge, rebase and clone?

Here is Oliver Steele's image of how it all fits together:

enter image description here

Include jQuery in the JavaScript Console

Per this answer:

fetch('https://code.jquery.com/jquery-latest.min.js').then(r => r.text()).then(r => eval(r))

For some reason I have to execute it twice to get the new '$' (which I have to do with the other methods as well), but it works.

This is the equivalent if your browser isn't so modern:

fetch('http://code.jquery.com/jquery-latest.min.js').then(function(r){return r.text()}).then(function(r){eval(r)})

SELECT only rows that contain only alphanumeric characters in MySQL

Your statement matches any string that contains a letter or digit anywhere, even if it contains other non-alphanumeric characters. Try this:

SELECT * FROM table WHERE column REGEXP '^[A-Za-z0-9]+$';

^ and $ require the entire string to match rather than just any portion of it, and + looks for 1 or more alphanumberic characters.

You could also use a named character class if you prefer:

SELECT * FROM table WHERE column REGEXP '^[[:alnum:]]+$';

How can I easily view the contents of a datatable or dataview in the immediate window

The Visual Studio debugger comes with four standard visualizers. These are the text, HTML, and XML visualizers, all of which work on string objects, and the dataset visualizer, which works for DataSet, DataView, and DataTable objects.

To use it, break into your code, mouse over your DataSet, expand the quick watch, view the Tables, expand that, then view Table[0] (for example). You will see something like {Table1} in the quick watch, but notice that there is also a magnifying glass icon. Click on that icon and your DataTable will open up in a grid view.

enter image description here

Match two strings in one line with grep

You could try something like this:

(pattern1.*pattern2|pattern2.*pattern1)

R: Plotting a 3D surface from x, y, z

You can use the function outer() to generate it.

Have a look at the demo for the function persp(), which is a base graphics function to draw perspective plots for surfaces.

Here is their first example:

x <- seq(-10, 10, length.out = 50)  
y <- x  
rotsinc <- function(x,y) {
    sinc <- function(x) { y <- sin(x)/x ; y[is.na(y)] <- 1; y }  
    10 * sinc( sqrt(x^2+y^2) )  
}

z <- outer(x, y, rotsinc)  
persp(x, y, z)

The same applies to surface3d():

require(rgl)  
surface3d(x, y, z)

How can I get a user's media from Instagram without authenticating as a user?

One more trick, search photos by hashtags:

GET https://www.instagram.com/graphql/query/?query_hash=3e7706b09c6184d5eafd8b032dbcf487&variables={"tag_name":"nature","first":25,"after":""}

Where:

query_hash - permanent value(i belive its hash of 17888483320059182, can be changed in future)

tag_name - the title speaks for itself

first - amount of items to get (I do not know why, but this value does not work as expected. The actual number of returned photos is slightly larger than the value multiplied by 4.5 (about 110 for the value 25, and about 460 for the value 100))

after - id of the last item if you want to get items from that id. Value of end_cursor from JSON response can be used here.

How do I check my gcc C++ compiler version for my Eclipse?

#include <stdio.h>

int main() {

  printf("gcc version: %d.%d.%d\n",__GNUC__,__GNUC_MINOR__,__GNUC_PATCHLEVEL__);
  return 0;
}

Evaluating a mathematical expression in a string

[I know this is an old question, but it is worth pointing out new useful solutions as they pop up]

Since python3.6, this capability is now built into the language, coined "f-strings".

See: PEP 498 -- Literal String Interpolation

For example (note the f prefix):

f'{2**4}'
=> '16'

Checking if a string is empty or null in Java

You can leverage Apache Commons StringUtils.isEmpty(str), which checks for empty strings and handles null gracefully.

Example:

System.out.println(StringUtils.isEmpty("")); // true
System.out.println(StringUtils.isEmpty(null)); // true

Google Guava also provides a similar, probably easier-to-read method: Strings.isNullOrEmpty(str).

Example:

System.out.println(Strings.isNullOrEmpty("")); // true
System.out.println(Strings.isNullOrEmpty(null)); // true

How to allow access outside localhost

you can also introspect all HTTP traffic running over your tunnels using ngrok , then you can expose using ngrok http --host-header=rewrite 4200

xcopy file, rename, suppress "Does xxx specify a file name..." message

So, there is a simple fix for this. It is admittedly awkward, but it works. xcopy will not prompt to find out if the destination is a directory or file IF the new file(filename) already exists. If you precede your xcopy command with a simple echo to the new filename, it will overwrite the empty file. Example

echo.>newfile.txt
xcopy oldfile.txt newfile.txt /Y

UITableViewCell Selected Background Color on Multiple Selection

UITableViewCell has an attribute multipleSelectionBackgroundView. https://developer.apple.com/documentation/uikit/uitableviewcell/1623226-selectedbackgroundview

Just create an UIView define the .backgroundColor of your choice and assign it to your cells .multipleSelectionBackgroundView attribute.

How to insert element into arrays at specific position?

Very simple 2 string answer to your question:

$array_1 = array(
  '0' => 'zero',
  '1' => 'one',
  '2' => 'two',
  '3' => 'three',
);

At first you insert anything to your third element with array_splice and then assign a value to this element:

array_splice($array_1, 3, 0 , true);
$array_1[3] = array('sample_key' => 'sample_value');

CSS: Truncate table cells, but fit as much as possible

<table border="1" style="width: 100%;">
    <colgroup>
        <col width="100%" />
        <col width="0%" />
    </colgroup>
    <tr>
        <td style="white-space: nowrap; text-overflow:ellipsis; overflow: hidden; max-width:1px;">This cell has more content.This cell has more content.This cell has more content.This cell has more content.This cell has more content.This cell has more content.</td>
        <td style="white-space: nowrap;">Less content here.</td>
    </tr>
</table>

http://jsfiddle.net/7CURQ/

How to add an item to a drop down list in ASP.NET?

Try this, it will insert the list item at index 0;

DropDownList1.Items.Insert(0, new ListItem("Add New", ""));

How can you get the Manifest Version number from the App's (Layout) XML variables?

You can't use it from the XML.

You need to extend the widget you are using in the XML and add the logic to set the text using what's mentioned on Konstantin Burov's answer.

How do I get a HttpServletRequest in my spring beans?

Better way is to autowire with a constructor:

private final HttpServletRequest httpServletRequest;

public ClassConstructor(HttpServletRequest httpServletRequest){
      this.httpServletRequest = httpServletRequest;
}

Add vertical scroll bar to panel

Assuming you're using winforms, default panel components does not offer you a way to disable the horizontal scrolling components. A workaround of this is to disable the auto scrolling and add a scrollbar yourself:

ScrollBar vScrollBar1 = new VScrollBar();
vScrollBar1.Dock = DockStyle.Right;
vScrollBar1.Scroll += (sender, e) => { panel1.VerticalScroll.Value = vScrollBar1.Value; };
panel1.Controls.Add(vScrollBar1);

Detailed discussion here.

Cannot uninstall angular-cli

I found a solution, first, delete the ng file with

sudo rm /usr/bin/ng

then install nvm (you need to restart your terminal to use nvm).

then install and use node 6 via nvm

nvm install 6
nvm use 6

finally install angular cli

npm install -g @angular/cli

this worked for me, I wanted to update to v1.0 stable from 1.0.28 beta, but couldn't uninstall the beta version (same situation that you desrcibed). Hope this works

What is an unsigned char?

This is implementation dependent, as the C standard does NOT define the signed-ness of char. Depending on the platform, char may be signed or unsigned, so you need to explicitly ask for signed char or unsigned char if your implementation depends on it. Just use char if you intend to represent characters from strings, as this will match what your platform puts in the string.

The difference between signed char and unsigned char is as you'd expect. On most platforms, signed char will be an 8-bit two's complement number ranging from -128 to 127, and unsigned char will be an 8-bit unsigned integer (0 to 255). Note the standard does NOT require that char types have 8 bits, only that sizeof(char) return 1. You can get at the number of bits in a char with CHAR_BIT in limits.h. There are few if any platforms today where this will be something other than 8, though.

There is a nice summary of this issue here.

As others have mentioned since I posted this, you're better off using int8_t and uint8_t if you really want to represent small integers.

How often should Oracle database statistics be run?

Make sure to balance the risk that fresh statistics cause undesirable changes to query plans against the risk that stale statistics can themselves cause query plans to change.

Imagine you have a bug database with a table ISSUE and a column CREATE_DATE where the values in the column increase more or less monotonically. Now, assume that there is a histogram on this column that tells Oracle that the values for this column are uniformly distributed between January 1, 2008 and September 17, 2008. This makes it possible for the optimizer to reasonably estimate the number of rows that would be returned if you were looking for all issues created last week (i.e. September 7 - 13). If the application continues to be used and the statistics are never updated, though, this histogram will be less and less accurate. So the optimizer will expect queries for "issues created last week" to be less and less accurate over time and may eventually cause Oracle to change the query plan negatively.

Function pointer as a member of a C struct

You can use also "void*" (void pointer) to send an address to the function.

typedef struct pstring_t {
    char * chars;
    int(*length)(void*);
} PString;

int length(void* self) {
    return strlen(((PString*)self)->chars);
}

PString initializeString() {
    PString str;
    str.length = &length;
    return str;
}

int main()
{
    PString p = initializeString();

    p.chars = "Hello";

    printf("Length: %i\n", p.length(&p));

    return 0;
}

Output:

Length: 5

Self-reference for cell, column and row in worksheet functions

In a VBA worksheet function UDF you use Application.Caller to get the range of cell(s) that contain the formula that called the UDF.

How to delete specific characters from a string in Ruby?

For those coming across this and looking for performance, it looks like #delete and #tr are about the same in speed and 2-4x faster than gsub.

text = "Here is a string with / some forwa/rd slashes"
tr = Benchmark.measure { 10000.times { text.tr('/', '') } }
# tr.total => 0.01
delete = Benchmark.measure { 10000.times { text.delete('/') } }
# delete.total => 0.01
gsub = Benchmark.measure { 10000.times { text.gsub('/', '') } }
# gsub.total => 0.02 - 0.04

YouTube API to fetch all videos on a channel

Try with like the following. It may help you.

https://gdata.youtube.com/feeds/api/videos?author=cnn&v=2&orderby=updated&alt=jsonc&q=news

Here author as you can specify your channel name and "q" as you can give your search key word.

Where does flask look for image files?

From the documentation:

Dynamic web applications also need static files. That’s usually where the CSS and JavaScript files are coming from. Ideally your web server is configured to serve them for you, but during development Flask can do that as well. Just create a folder called static in your package or next to your module and it will be available at /static on the application.

To generate URLs for static files, use the special 'static' endpoint name:

url_for('static', filename='style.css')

The file has to be stored on the filesystem as static/style.css.

How to copy in bash all directory and files recursive?

code for a simple copy.

cp -r ./SourceFolder ./DestFolder

code for a copy with success result

cp -rv ./SourceFolder ./DestFolder

code for Forcefully if source contains any readonly file it will also copy

cp -rf ./SourceFolder ./DestFolder

for details help

cp --help

How to monitor the memory usage of Node.js?

Also, if you'd like to know global memory rather than node process':

var os = require('os');

os.freemem();
os.totalmem();

See documentation

Running code after Spring Boot starts

Try:

@Configuration
@EnableAutoConfiguration
@ComponentScan
public class Application extends SpringBootServletInitializer {

    @SuppressWarnings("resource")
    public static void main(final String[] args) {
        ConfigurableApplicationContext context = SpringApplication.run(Application.class, args);

        context.getBean(Table.class).fillWithTestdata(); // <-- here
    }
}

Tomcat starts but home page cannot open with url http://localhost:8080

If you have your tomcat started (in linux check with ps -ef | grep java) and you see it opened the port 8080 or the one you configured in server.xml (check with netstat --tcp -na | grep <port number>) but you still cannot access it in your browser check the following:

  1. It may start but with a delay of 3-5 minutes. Check the logs/catalina.out. You should see something like this when the server started completely.
    INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 38442 ms
    If you don't have this INFO line your server startup is not complete yet. The problem may occur due to the SecureRandom class responsible to provide random Session IDs and which can cause big delays during startup. Check more details and the solution here.
  2. Check your firewall (on linux iptables -L -n): You can try to reset your firewall completely iptables -F if you are not into an exposed environment. However, pay attention, that leaves you without protection therefore it can be dangerous.
  3. Check your selinux (if you are on linux).

These are some of the most forgotten and not obvious issues in having your Apache Tomcat up and running.

Counting Number of Letters in a string variable

What is wrong with using string.Length?

// len will be 5
int len = "Hello".Length;

Is there any way to configure multiple registries in a single npmrc file

As of 13 April 2020 there is no such functionality unless you are able to use different scopes, but you may use the postinstall script as a workaround. It is always executed, well, after each npm install:

Say you have your .npmrc configured to install @foo-org/foo-pack-private from your private github repo, but the @foo-org/foo-pack-public public package is on npm (under the same scope: foo-org).

Your postinstall might look like this:

"scripts": {
    ...
    "postinstall": "mv .npmrc .npmrcc && npm i @foo-org/foo-pack --dry-run && mv .npmrcc .npmrc".
}

Don't forget to remove @foo-pack/foo-org from the dependencies array to make sure npm install does not try and get it from github and to add the --dry-run flag that makes sure package.json and package-lock.json stay unchanged after npm install.

SQL Server: the maximum number of rows in table

It depends, but I would say it is better to keep everything in one table for that sake of simplicity.

100,000 rows a day is not really that much of an enormous amount. (Depending on your server hardware). I have personally seen MSSQL handle up to 100M rows in a single table without any problems. As long as your keep your indexes in order it should be all good. The key is to have heaps of memory so that indexes don't have to be swapped out to disk.

On the other hand, it depends on how you are using the data, if you need to make lots of query's, and its unlikely data will be needed that spans multiple days (so you won't need to join the tables) it will be faster to separate out it out into multiple tables. This is often used in applications such as industrial process control where you might be reading the value on say 50,000 instruments every 10 seconds. In this case speed is extremely important, but simplicity is not.

Expand a div to fill the remaining width

A slightly different implementation,

Two div panels(content+extra), side by side, content panel expands if extra panel is not present.

jsfiddle: http://jsfiddle.net/qLTMf/1722/

Javascript to set hidden form value on drop down change

Just to be different, changed my answer so that this question doesn't have 5 answers with the same code.

<html>
<head>
   <title>Page</title>  
   <script src="jquery-1.3.2.min.js"></script>
   <script>
       $(function() {
           var select = $("body").append('<form></form>').children('form')
                .append('<input type="hidden" value="" />').children('input[type=hidden]')
                .attr('id', 'hiddenValue').end()
                .append('<select></select>').children('select')
                .attr('id', 'dropdown')
                .change(function() {
                    alert($(this).val());
                });

           $.each({ one: 1, two: 2, three: 3, four: 4, five: 5 }, function(txt, val) {
               select.append('<option value="' + val + '">' + txt + '</option>');
           });
       });
</script>
</head>
   <body></body>
</html>

Free XML Formatting tool

You could also try http://xmltoolbox.appspot.com/ it is an online xml formatter. You just paste your xml into a large text area field and press "format xml" then it pretty prints the xml in the text area so its easy to read or copy.

There is also a nice little filter feature that allows you to see all of a certain element.

Hope you will enjoy the tool

How do you see the entire command history in interactive Python?

With python 3 interpreter the history is written to
~/.python_history

Retrieve version from maven pom.xml in code

With reference to ketankk's answer:

Unfortunately, adding this messed with how my application dealt with resources:

<build>
  <resources>
    <resource>
      <directory>src/main/resources</directory>
      <filtering>true</filtering>
    </resource>
  </resources>   
</build>

But using this inside maven-assemble-plugin's < manifest > tag did the trick:

<addDefaultImplementationEntries>true</addDefaultImplementationEntries>
<addDefaultSpecificationEntries>true</addDefaultSpecificationEntries>

So I was able to get version using

String version = getClass().getPackage().getImplementationVersion();

Change url query string value using jQuery

purls $.params() used without a parameter will give you a key-value object of the parameters.

jQuerys $.param() will build a querystring from the supplied object/array.

var params = parsedUrl.param();
delete params["page"];

var newUrl = "?page=" + $(this).val() + "&" + $.param(params);

Update
I've no idea why I used delete here...

var params = parsedUrl.param();
params["page"] = $(this).val();

var newUrl = "?" + $.param(params);

how to concat two columns into one with the existing column name in mysql?

Just Remove * from your select clause, and mention all column names explicitly and omit the FIRSTNAME column. After this write CONCAT(FIRSTNAME, ',', LASTNAME) AS FIRSTNAME. The above query will give you the only one FIRSTNAME column.

How to redirect stdout to both file and console with scripting?

I tried this:

"""
Transcript - direct print output to a file, in addition to terminal.

Usage:
    import transcript
    transcript.start('logfile.log')
    print("inside file")
    transcript.stop()
    print("outside file")
"""

import sys

class Transcript(object):

    def __init__(self, filename):
        self.terminal = sys.stdout, sys.stderr
        self.logfile = open(filename, "a")

    def write(self, message):
        self.terminal.write(message)
        self.logfile.write(message)

    def flush(self):
        # this flush method is needed for python 3 compatibility.
        # this handles the flush command by doing nothing.
        # you might want to specify some extra behavior here.
        pass

def start(filename):
    """Start transcript, appending print output to given filename"""
    sys.stdout = Transcript(filename)

def stop():
    """Stop transcript and return print functionality to normal"""
    sys.stdout.logfile.close()
    sys.stdout = sys.stdout.terminal
    sys.stderr = sys.stderr.terminal

How do I restore a dump file from mysqldump?

./mysql -u <username> -p <password> -h <host-name like localhost> <database-name> < db_dump-file

Text was truncated or one or more characters had no match in the target code page including the primary key in an unpivot

I know this is an old question. The way I solved it - after failing by increasing the length or even changing to data type text - was creating an XLSX file and importing. It accurately detected the data type instead of setting all columns as varchar(50). Turns out nvarchar(255) for that column would have done it too.

label or @html.Label ASP.net MVC 4

The helpers are there mainly to help you display labels, form inputs, etc for the strongly typed properties of your model. By using the helpers and Visual Studio Intellisense, you can greatly reduce the number of typos that you could make when generating a web page.

With that said, you can continue to create your elements manually for both properties of your view model or items that you want to display that are not part of your view model.

Get the device width in javascript

Ya mybe u can use document.documentElement.clientWidth to get the device width of client and keep tracking the device width by put on setInterval

just like

setInterval(function(){
        width = document.documentElement.clientWidth;
        console.log(width);
    }, 1000);

Regular expression for number with length of 4, 5 or 6

Try this:

^[0-9]{4,6}$

{4,6} = between 4 and 6 characters, inclusive.

C++ terminate called without an active exception

Eric Leschinski and Bartosz Milewski have given the answer already. Here, I will try to present it in a more beginner friendly manner.

Once a thread has been started within a scope (which itself is running on a thread), one must explicitly ensure one of the following happens before the thread goes out of scope:

  • The runtime exits the scope, only after that thread finishes executing. This is achieved by joining with that thread. Note the language, it is the outer scope that joins with that thread.
  • The runtime leaves the thread to run on its own. So, the program will exit the scope, whether this thread finished executing or not. This thread executes and exits by itself. This is achieved by detaching the thread. This could lead to issues, for example, if the thread refers to variables in that outer scope.

Note, by the time the thread is joined with or detached, it may have well finished executing. Still either of the two operations must be performed explicitly.

Regex for empty string or white space

If you're using jQuery, you have .trim().

if ($("#siren").val().trim() == "") {
  // it's empty
}

How to get the host name of the current machine as defined in the Ansible hosts file?

The necessary variable is inventory_hostname.

- name: Install this only for local dev machine
  pip: name=pyramid
  when: inventory_hostname == "local"

It is somewhat hidden in the documentation at the bottom of this section.

How to read a list of files from a folder using PHP?

There is a glob. In this webpage there are good article how to list files in very simple way:

How to read a list of files from a folder using PHP

Creating a PHP header/footer

Just create the header.php file, and where you want to use it do:

<?php
include('header.php');
?>

Same with the footer. You don't need php tags in these files if you just have html.

See more about include here:

http://php.net/manual/en/function.include.php

What is a good practice to check if an environmental variable exists or not?

My comment might not be relevant to the tags given. However, I was lead to this page from my search. I was looking for similar check in R and I came up the following with the help of @hugovdbeg post. I hope it would be helpful for someone who is looking for similar solution in R

'USERNAME' %in% names(Sys.getenv())

What is the 'open' keyword in Swift?

open is only for another module for example: cocoa pods, or unit test, we can inherit or override

How to use PHP string in mySQL LIKE query?

DO it like

$query = mysql_query("SELECT * FROM table WHERE the_number LIKE '$yourPHPVAR%'");

Do not forget the % at the end

How to detect when a youtube video finishes playing?

This can be done through the youtube player API:

http://jsfiddle.net/7Gznb/

Working example:

    <div id="player"></div>

    <script src="http://www.youtube.com/player_api"></script>

    <script>

        // create youtube player
        var player;
        function onYouTubePlayerAPIReady() {
            player = new YT.Player('player', {
              width: '640',
              height: '390',
              videoId: '0Bmhjf0rKe8',
              events: {
                onReady: onPlayerReady,
                onStateChange: onPlayerStateChange
              }
            });
        }

        // autoplay video
        function onPlayerReady(event) {
            event.target.playVideo();
        }

        // when video ends
        function onPlayerStateChange(event) {        
            if(event.data === 0) {          
                alert('done');
            }
        }

    </script>

Getting date format m-d-Y H:i:s.u from milliseconds

Based on @ArchCodeMonkey answer.

If you have declare(strict_types=1) you must cast second argument to string

enter image description here

Get text from pressed button

Try to use:

String buttonText = ((Button)v).getText().toString();

Call angularjs function using jquery/javascript

Please check this answer

// In angularJS script
$scope.foo = function() {
    console.log('test');
};
$window.angFoo = function() {
    $scope.foo();
    $scope.$apply(); 
};
    
// In jQuery
if (window.angFoo) {
    window.angFoo();
}

Send a file via HTTP POST with C#

Using .NET 4.5 (or .NET 4.0 by adding the Microsoft.Net.Http package from NuGet) there is an easier way to simulate form requests. Here is an example:

private async Task<System.IO.Stream> Upload(string actionUrl, string paramString, Stream paramFileStream, byte [] paramFileBytes)
{
    HttpContent stringContent = new StringContent(paramString);
    HttpContent fileStreamContent = new StreamContent(paramFileStream);
    HttpContent bytesContent = new ByteArrayContent(paramFileBytes);
    using (var client = new HttpClient())
    using (var formData = new MultipartFormDataContent())
    {
        formData.Add(stringContent, "param1", "param1");
        formData.Add(fileStreamContent, "file1", "file1");
        formData.Add(bytesContent, "file2", "file2");
        var response = await client.PostAsync(actionUrl, formData);
        if (!response.IsSuccessStatusCode)
        {
            return null;
        }
        return await response.Content.ReadAsStreamAsync();
    }
}

How to do an array of hashmaps?

The Java Language Specification, section 15.10, states:

An array creation expression creates an object that is a new array whose elements are of the type specified by the PrimitiveType or ClassOrInterfaceType. It is a compile-time error if the ClassOrInterfaceType does not denote a reifiable type (§4.7).

and

The rules above imply that the element type in an array creation expression cannot be a parameterized type, other than an unbounded wildcard.

The closest you can do is use an unchecked cast, either from the raw type, as you have done, or from an unbounded wildcard:

 HashMap<String, String>[] responseArray = (Map<String, String>[]) new HashMap<?,?>[games.size()];

Your version is clearly better :-)

How to change a PG column to NULLABLE TRUE?

From the fine manual:

ALTER TABLE mytable ALTER COLUMN mycolumn DROP NOT NULL;

There's no need to specify the type when you're just changing the nullability.

Insert ellipsis (...) into HTML tag if content too wide

My answer only supports single line text. Check out gfullam's comment below for the multi-line fork, it looks pretty promising.

I rewrote the code from the first answer a few times, and I think this should be the fastest.

It first finds an "Estimated" text length, and then adds or removes a character until the width is correct.

The logic it uses is shown below:

enter image description here

After an "estimated" text length is found, characters are added or removed until the desired width is reached.

I'm sure it needs some tweaking, but here's the code:

(function ($) {
    $.fn.ellipsis = function () {
        return this.each(function () {
            var el = $(this);

            if (el.css("overflow") == "hidden") {
                var text = el.html().trim();
                var t = $(this.cloneNode(true))
                                        .hide()
                                        .css('position', 'absolute')
                                        .css('overflow', 'visible')
                                        .width('auto')
                                        .height(el.height())
                                        ;
                el.after(t);

                function width() { return t.width() > el.width(); };

                if (width()) {

                    var myElipse = "....";

                    t.html(text);

                    var suggestedCharLength = (text.length * el.width() / t.width()) - myElipse.length;

                    t.html(text.substr(0, suggestedCharLength) + myElipse);

                    var x = 1;
                    if (width()) {
                        while (width()) {
                            t.html(text.substr(0, suggestedCharLength - x) + myElipse);
                            x++;
                        }
                    }
                    else {
                        while (!width()) {
                            t.html(text.substr(0, suggestedCharLength + x) + myElipse);
                            x++;
                        }
                        x--;
                        t.html(text.substr(0, suggestedCharLength + x) + myElipse);
                    }

                    el.html(t.html());
                    t.remove();
                }
            }
        });
    };
})(jQuery);

How to get current formatted date dd/mm/yyyy in Javascript and append it to an input

I honestly suggest that you use moment.js. Just download moment.min.js and then use this snippet to get your date in whatever format you want:

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

     // set an element
     $("#date").val( moment().format('MMM D, YYYY') );

     // set a variable
     var today = moment().format('D MMM, YYYY');

});
</script>

Use following chart for date formats:

enter image description here

Please enter a commit message to explain why this merge is necessary, especially if it merges an updated upstream into a topic branch

I had the same issue when I was using GIT bash to merge master branch in to my feature branch. I followed the following steps to overcome this.

  1. press 'i' (To insert a merge message)
  2. write your merge message
  3. press esc button (To go back)
  4. write ':wq' (write & quit)
  5. then press enter

Socket accept - "Too many open files"

I had similar problem. Quick solution is :

ulimit -n 4096

explanation is as follows - each server connection is a file descriptor. In CentOS, Redhat and Fedora, probably others, file user limit is 1024 - no idea why. It can be easily seen when you type: ulimit -n

Note this has no much relation to system max files (/proc/sys/fs/file-max).

In my case it was problem with Redis, so I did:

ulimit -n 4096
redis-server -c xxxx

in your case instead of redis, you need to start your server.

Getting the index of a particular item in array

FindIndex Extension

static class ArrayExtensions
{
    public static int FindIndex<T>(this T[] array, Predicate<T> match)
    {
        return Array.FindIndex(array, match);
    }
}

Usage

int[] array = { 9,8,7,6,5 };

var index = array.FindIndex(i => i == 7);

Console.WriteLine(index); // Prints "2"

Here's a fiddle with it.


Bonus: IndexOf Extension

I wrote this first not reading the question properly...

static class ArrayExtensions
{
    public static int IndexOf<T>(this T[] array, T value)
    {
        return Array.IndexOf(array, value);
    }   
}

Usage

int[] array = { 9,8,7,6,5 };

var index = array.IndexOf(7);

Console.WriteLine(index); // Prints "2"

Here's a fiddle with it.

How to start and stop/pause setInterval?

See Working Demo on jsFiddle: http://jsfiddle.net/qHL8Z/3/

_x000D_
_x000D_
$(function() {_x000D_
  var timer = null,_x000D_
    interval = 1000,_x000D_
    value = 0;_x000D_
_x000D_
  $("#start").click(function() {_x000D_
    if (timer !== null) return;_x000D_
    timer = setInterval(function() {_x000D_
      $("#input").val(++value);_x000D_
    }, interval);_x000D_
  });_x000D_
_x000D_
  $("#stop").click(function() {_x000D_
    clearInterval(timer);_x000D_
    timer = null_x000D_
  });_x000D_
});
_x000D_
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>_x000D_
<input type="number" id="input" />_x000D_
<input id="stop" type="button" value="stop" />_x000D_
<input id="start" type="button" value="start" />
_x000D_
_x000D_
_x000D_

Listening for variable changes in JavaScript

Using Prototype: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty

_x000D_
_x000D_
// Console_x000D_
function print(t) {_x000D_
  var c = document.getElementById('console');_x000D_
  c.innerHTML = c.innerHTML + '<br />' + t;_x000D_
}_x000D_
_x000D_
// Demo_x000D_
var myVar = 123;_x000D_
_x000D_
Object.defineProperty(this, 'varWatch', {_x000D_
  get: function () { return myVar; },_x000D_
  set: function (v) {_x000D_
    myVar = v;_x000D_
    print('Value changed! New value: ' + v);_x000D_
  }_x000D_
});_x000D_
_x000D_
print(varWatch);_x000D_
varWatch = 456;_x000D_
print(varWatch);
_x000D_
<pre id="console">_x000D_
</pre>
_x000D_
_x000D_
_x000D_

Other example

_x000D_
_x000D_
// Console_x000D_
function print(t) {_x000D_
  var c = document.getElementById('console');_x000D_
  c.innerHTML = c.innerHTML + '<br />' + t;_x000D_
}_x000D_
_x000D_
// Demo_x000D_
var varw = (function (context) {_x000D_
  return function (varName, varValue) {_x000D_
    var value = varValue;_x000D_
  _x000D_
    Object.defineProperty(context, varName, {_x000D_
      get: function () { return value; },_x000D_
      set: function (v) {_x000D_
        value = v;_x000D_
        print('Value changed! New value: ' + value);_x000D_
      }_x000D_
    });_x000D_
  };_x000D_
})(window);_x000D_
_x000D_
varw('varWatch'); // Declare_x000D_
print(varWatch);_x000D_
varWatch = 456;_x000D_
print(varWatch);_x000D_
_x000D_
print('---');_x000D_
_x000D_
varw('otherVarWatch', 123); // Declare with initial value_x000D_
print(otherVarWatch);_x000D_
otherVarWatch = 789;_x000D_
print(otherVarWatch);
_x000D_
<pre id="console">_x000D_
</pre>
_x000D_
_x000D_
_x000D_

Get div to take up 100% body height, minus fixed-height header and footer

You can take advatange of the css property Box Sizing.

#content { 
    height: 100%;
    -webkit-box-sizing: border-box; /* Safari/Chrome, other WebKit */
    -moz-box-sizing: border-box;    /* Firefox, other Gecko */
    box-sizing: border-box;         /* Opera/IE 8+ */
    padding-top: 50px;
    margin-top: -50px;
    padding-bottom: 50px;
    margin-bottom: -50px;
}

See the JsFiddle.

Multiline for WPF TextBox

The only property corresponding in WPF to the

Winforms property: TextBox.Multiline = true

is the WPF property: TextBox.AcceptsReturn = true.

<TextBox AcceptsReturn="True" ...... />

All other settings, such as VerticalAlignement, WordWrap etc., only control how the TextBox interacts in the UI but do not affect the Multiline behaviour.

Change / Add syntax highlighting for a language in Sublime 2/3

Use the PackageResourceViewer plugin installed via Package Control (as mentioned by MattDMo). This allows you to override the compressed resources by simply opening it in Sublime Text and saving the file. It automatically saves only the edited resources to %APPDATA%/Roaming/Sublime Text 3/Packages/ or ~/.config/sublime-text-3/Packages/.

Specific to the op, once the plugin is installed, execute the PackageResourceViewer: Open Resource command. Then select JavaScript followed by JavaScript.tmLanguage. This will open an xml file in the editor. You can edit any of the language definitions and save the file. This will write an override copy of the JavaScript.tmLanguage file in the user directory.

The same method can be used to edit the language definition of any language in the system.

Pass Array Parameter in SqlCommand

Passing an array of items as a collapsed parameter to the WHERE..IN clause will fail since query will take form of WHERE Age IN ("11, 13, 14, 16").

But you can pass your parameter as an array serialized to XML or JSON:

Using nodes() method:

StringBuilder sb = new StringBuilder();

foreach (ListItem item in ddlAge.Items)
  if (item.Selected)
    sb.Append("<age>" + item.Text + "</age>"); // actually it's xml-ish

sqlComm.CommandText = @"SELECT * from TableA WHERE Age IN (
    SELECT Tab.col.value('.', 'int') as Age from @Ages.nodes('/age') as Tab(col))";
sqlComm.Parameters.Add("@Ages", SqlDbType.NVarChar);
sqlComm.Parameters["@Ages"].Value = sb.ToString();

Using OPENXML method:

using System.Xml.Linq;
...
XElement xml = new XElement("Ages");

foreach (ListItem item in ddlAge.Items)
  if (item.Selected)
    xml.Add(new XElement("age", item.Text);

sqlComm.CommandText = @"DECLARE @idoc int;
    EXEC sp_xml_preparedocument @idoc OUTPUT, @Ages;
    SELECT * from TableA WHERE Age IN (
    SELECT Age from OPENXML(@idoc, '/Ages/age') with (Age int 'text()')
    EXEC sp_xml_removedocument @idoc";
sqlComm.Parameters.Add("@Ages", SqlDbType.Xml);
sqlComm.Parameters["@Ages"].Value = xml.ToString();

That's a bit more on the SQL side and you need a proper XML (with root).

Using OPENJSON method (SQL Server 2016+):

using Newtonsoft.Json;
...
List<string> ages = new List<string>();

foreach (ListItem item in ddlAge.Items)
  if (item.Selected)
    ages.Add(item.Text);

sqlComm.CommandText = @"SELECT * from TableA WHERE Age IN (
    select value from OPENJSON(@Ages))";
sqlComm.Parameters.Add("@Ages", SqlDbType.NVarChar);
sqlComm.Parameters["@Ages"].Value = JsonConvert.SerializeObject(ages);

Note that for the last method you also need to have Compatibility Level at 130+.

Can CSS force a line break after each word in an element?

I faced the same problem, and none of the options here helped me. Some mail services do not support specified styles. Here is my version, which solved the problem and works everywhere I checked:

<table>
    <tr>
        <td width="1">Gargantuan Word</td>
    </tr>
</table>

OR using CSS:

<table>
    <tr>
        <td style="width:1px">Gargantuan Word</td>
    </tr>
</table>

Git conflict markers

The line (or lines) between the lines beginning <<<<<<< and ====== here:

<<<<<<< HEAD:file.txt
Hello world
=======

... is what you already had locally - you can tell because HEAD points to your current branch or commit. The line (or lines) between the lines beginning ======= and >>>>>>>:

=======
Goodbye
>>>>>>> 77976da35a11db4580b80ae27e8d65caf5208086:file.txt

... is what was introduced by the other (pulled) commit, in this case 77976da35a11. That is the object name (or "hash", "SHA1sum", etc.) of the commit that was merged into HEAD. All objects in git, whether they're commits (version), blobs (files), trees (directories) or tags have such an object name, which identifies them uniquely based on their content.

ElasticSearch - Return Unique Values

Elasticsearch 1.1+ has the Cardinality Aggregation which will give you a unique count

Note that it is actually an approximation and accuracy may diminish with high-cardinality datasets, but it's generally pretty accurate in my testing.

You can also tune the accuracy with the precision_threshold parameter. The trade-off, or course, is memory usage.

This graph from the docs shows how a higher precision_threshold leads to much more accurate results.


Relative error vs threshold

How to handle invalid SSL certificates with Apache HttpClient?

I happened to face the same issue, all of a sudden all my imports were missing. I tried deleting all the contents in my .m2 folder. And trying to re-import everything , but still nothing worked. Finally what I did was opened the website for which the IDE was complaining that it couldn't download in my browser. And saw the certificate it was using, and saw in my

$ keytool -v -list  PATH_TO_JAVA_KEYSTORE

Path to my keystore was /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/security/cacerts

that particular certificate was not there.

So all you have to do is put the certificate into the JAVA JVM keystore again. It can be done using the below command.

$ keytool -import -alias ANY_NAME_YOU_WANT_TO_GIVE -file PATH_TO_YOUR_CERTIFICATE -keystore PATH_OF_JAVA_KEYSTORE

If it asks for password, try the default password 'changeit' If you get permission error when running the above command. In windows open it in administration mode. In mac and unix use sudo.

After you have successfully added the key, You can view it using :

$ keytool -v -list  /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/security/cacerts 

You can view just the SHA-1 using teh command

$ keytool -list  /Library/Java/JavaVirtualMachines/jdk1.8.0_171.jdk/Contents/Home/jre/lib/security/cacerts 

Handlebars/Mustache - Is there a built in way to loop through the properties of an object?

It's actually quite easy to implement as a helper:

Handlebars.registerHelper('eachProperty', function(context, options) {
    var ret = "";
    for(var prop in context)
    {
        ret = ret + options.fn({property:prop,value:context[prop]});
    }
    return ret;
});

Then using it like so:

{{#eachProperty object}}
    {{property}}: {{value}}<br/>
{{/eachProperty }}

PyCharm error: 'No Module' when trying to import own module (python script)

PyCharm Community/Professional 2018.2.1

I was having this problem just now and I was able to solve it in sort of a similar way that @Beatriz Fonseca and @Julie pointed out.

If you go to File -> Settings -> Project: YourProjectName -> Project Structure, you'll have a directory layout of the project you're currently working in. You'll have to go through your directories and label them as being either the Source directory for all your Source files, or as a Resource folder for files that are strictly for importing.

You'll also want to make sure that you place __init__.py files within your resource directories, or really anywhere that you want to import from, and it'll work perfectly fine.

I hope this answer helps someone, and hopefully JetBrains will fix this annoying bug.

When should I use nil and NULL in Objective-C?

They both are just typecast zero's. Functionally, there's no difference between them. ie.,

#define NULL ((void*)0)
#define nil ((id)0)

There is a difference, but only to yourself and other humans that read the code, the compiler doesn't care.

One more thing nil is an object value while NULL is a generic pointer value.

how to pass command line arguments to main method dynamically

Run ---> Debug Configuration ---> YourConfiguration ---> Arguments tab

enter image description here

Rename multiple files in a directory in Python

It seems that your problem is more in determining the new file name rather than the rename itself (for which you could use the os.rename method).

It is not clear from your question what the pattern is that you want to be renaming. There is nothing wrong with string manipulation. A regular expression may be what you need here.

GoogleMaps API KEY for testing

There seems no way to have google maps api key free without credit card. To test the functionality of google map you can use it while leaving the api key field "EMPTY". It will show a message saying "For Development Purpose Only". And that way you can test google map functionality without putting billing information for google map api key.

<script src="https://maps.googleapis.com/maps/api/js?key=&callback=initMap" async defer></script>

Javascript setInterval not working

That's because you should pass a function, not a string:

function funcName() {
    alert("test");
}

setInterval(funcName, 10000);

Your code has two problems:

  • var func = funcName(); calls the function immediately and assigns the return value.
  • Just "func" is invalid even if you use the bad and deprecated eval-like syntax of setInterval. It would be setInterval("func()", 10000) to call the function eval-like.

Mod of negative number is melting my brain

ShreevatsaR's answer won't work for all cases, even if you add "if(m<0) m=-m;", if you account for negative dividends/divisors.

For example, -12 mod -10 will be 8, and it should be -2.

The following implementation will work for both positive and negative dividends / divisors and complies with other implementations (namely, Java, Python, Ruby, Scala, Scheme, Javascript and Google's Calculator):

internal static class IntExtensions
{
    internal static int Mod(this int a, int n)
    {
        if (n == 0)
            throw new ArgumentOutOfRangeException("n", "(a mod 0) is undefined.");

        //puts a in the [-n+1, n-1] range using the remainder operator
        int remainder = a%n;

        //if the remainder is less than zero, add n to put it in the [0, n-1] range if n is positive
        //if the remainder is greater than zero, add n to put it in the [n-1, 0] range if n is negative
        if ((n > 0 && remainder < 0) ||
            (n < 0 && remainder > 0))
            return remainder + n;
        return remainder;
    }
}

Test suite using xUnit:

    [Theory]
    [PropertyData("GetTestData")]
    public void Mod_ReturnsCorrectModulo(int dividend, int divisor, int expectedMod)
    {
        Assert.Equal(expectedMod, dividend.Mod(divisor));
    }

    [Fact]
    public void Mod_ThrowsException_IfDivisorIsZero()
    {
        Assert.Throws<ArgumentOutOfRangeException>(() => 1.Mod(0));
    }

    public static IEnumerable<object[]> GetTestData
    {
        get
        {
            yield return new object[] {1, 1, 0};
            yield return new object[] {0, 1, 0};
            yield return new object[] {2, 10, 2};
            yield return new object[] {12, 10, 2};
            yield return new object[] {22, 10, 2};
            yield return new object[] {-2, 10, 8};
            yield return new object[] {-12, 10, 8};
            yield return new object[] {-22, 10, 8};
            yield return new object[] { 2, -10, -8 };
            yield return new object[] { 12, -10, -8 };
            yield return new object[] { 22, -10, -8 };
            yield return new object[] { -2, -10, -2 };
            yield return new object[] { -12, -10, -2 };
            yield return new object[] { -22, -10, -2 };
        }
    }

ReactJS call parent method

To do this you pass a callback as a property down to the child from the parent.

For example:

var Parent = React.createClass({

    getInitialState: function() {
        return {
            value: 'foo'
        }
    },

    changeHandler: function(value) {
        this.setState({
            value: value
        });
    },

    render: function() {
        return (
            <div>
                <Child value={this.state.value} onChange={this.changeHandler} />
                <span>{this.state.value}</span>
            </div>
        );
    }
});

var Child = React.createClass({
    propTypes: {
        value:      React.PropTypes.string,
        onChange:   React.PropTypes.func
    },
    getDefaultProps: function() {
        return {
            value: ''
        };
    },
    changeHandler: function(e) {
        if (typeof this.props.onChange === 'function') {
            this.props.onChange(e.target.value);
        }
    },
    render: function() {
        return (
            <input type="text" value={this.props.value} onChange={this.changeHandler} />
        );
    }
});

In the above example, Parent calls Child with a property of value and onChange. The Child in return binds an onChange handler to a standard <input /> element and passes the value up to the Parent's callback if it's defined.

As a result the Parent's changeHandler method is called with the first argument being the string value from the <input /> field in the Child. The result is that the Parent's state can be updated with that value, causing the parent's <span /> element to update with the new value as you type it in the Child's input field.

What's the proper way to compare a String to an enum value?

Define enum:

public enum Gesture
{
    ROCK, PAPER, SCISSORS;
}

Define a method to check enum content:

private boolean enumContainsValue(String value)
{
    for (Gesture gesture : Gesture.values())
    {
        if (gesture.name().equals(value))
        {
            return true;
        }
    }

    return false;
}

And use it:

String gestureString = "PAPER";

if (enumContainsValue(gestureString))
{
    Gesture gestureId = Gesture.valueOf(gestureString);

    switch (gestureId)
    {
        case ROCK:
            Log.i("TAG", "ROCK");
            break;

        case PAPER:
            Log.i("TAG", "PAPER");
            break;

        case SCISSORS:
            Log.i("TAG", "SCISSORS");
            break;
    }
}

Configure apache to listen on port other than 80

Run this command if your ufw(Uncomplicatd Firewall) is enabled . Add for Example port 8080

$ sudo ufw allow 8080/tcp

And you can check the status by running

$ sudo ufw status

For more info check : https://linuxhint.com/ubuntu_allow_port_firewall

ASP.NET MVC passing an ID in an ActionLink to the controller

Doesn't look like you are using the correct overload of ActionLink. Try this:-

<%=Html.ActionLink("Modify Villa", "Modify", new {id = "1"})%>

This assumes your view is under the /Views/Villa folder. If not then I suspect you need:-

<%=Html.ActionLink("Modify Villa", "Modify", "Villa", new {id = "1"}, null)%>

Shell script to send email

top -b -n 1 | mail -s "any subject" [email protected]

Remove ListView items in Android

It's simple .First you should clear your collection and after clear list like this code :

 yourCollection.clear();
 setListAdapter(null);

git pull displays "fatal: Couldn't find remote ref refs/heads/xxxx" and hangs up

In my case, it happenned for the master branch. Later found that my access to the project was accidentally revoked by the project manager. To cross-check, I visited the review site and couldn't see any commits of the said branch and others for that project.

How do you specifically order ggplot2 x axis instead of alphabetical order?

The accepted answer offers a solution which requires changing of the underlying data frame. This is not necessary. One can also simply factorise within the aes() call directly or create a vector for that instead.

This is certainly not much different than user Drew Steen's answer, but with the important difference of not changing the original data frame.

level_order <- c('virginica', 'versicolor', 'setosa') #this vector might be useful for other plots/analyses

ggplot(iris, aes(x = factor(Species, level = level_order), y = Petal.Width)) + geom_col()

or

level_order <- factor(iris$Species, level = c('virginica', 'versicolor', 'setosa'))

ggplot(iris, aes(x = level_order, y = Petal.Width)) + geom_col()

or
directly in the aes() call without a pre-created vector:

ggplot(iris, aes(x = factor(Species, level = c('virginica', 'versicolor', 'setosa')), y = Petal.Width)) + geom_col()

that's for the first version

jquery equivalent for JSON.stringify

There is no such functionality in jQuery. Use JSON.stringify or alternatively any jQuery plugin with similar functionality (e.g jquery-json).

Rename multiple files based on pattern in Unix

Generic command would be

find /path/to/files -name '<search>*' -exec bash -c 'mv $0 ${0/<search>/<replace>}' {} \;

where <search> and <replace> should be replaced with your source and target respectively.

As a more specific example tailored to your problem (should be run from the same folder where your files are), the above command would look like:

find . -name 'gfh*' -exec bash -c 'mv $0 ${0/gfh/jkl}' {} \;

For a "dry run" add echo before mv, so that you'd see what commands are generated:

find . -name 'gfh*' -exec bash -c 'echo mv $0 ${0/gfh/jkl}' {} \;

How to configure socket connect timeout

it might be too late but there is neat solution based on Task.WaitAny (c# 5 +) :

 public static bool ConnectWithTimeout(this Socket socket, string host, int port, int timeout)
        {
            bool connected = false;
            Task result = socket.ConnectAsync(host, port);               
            int index = Task.WaitAny(new[] { result }, timeout);
            connected = socket.Connected;
            if (!connected) {
              socket.Close();
            }

            return connected;
        }

How can I initialize base class member variables in derived class constructor?

Why can't you do it? Because the language doesn't allow you to initializa a base class' members in the derived class' initializer list.

How can you get this done? Like this:

class A
{
public:
    A(int a, int b) : a_(a), b_(b) {};
    int a_, b_;
};

class B : public A
{
public:
    B() : A(0,0) 
    {
    }
};

Transparent background in JPEG image

JPG does not support a transparent background, you can easily convert it to a PNG which does support a transparent background by opening it in near any photo editor and save it as a.PNG

Delete entire row if cell contains the string X

This is not necessarily a VBA task - This specific task is easiest sollowed with Auto filter.

1.Insert Auto filter (In Excel 2010 click on home-> (Editing) Sort & Filter -> Filter)
2. Filter on the 'Websites' column
3. Mark the 'none' and delete them
4. Clear filter

Android - Best and safe way to stop thread

I used this method.

Looper.myLooper().quit();

you can try.

Activity <App Name> has leaked ServiceConnection <ServiceConnection Name>@438030a8 that was originally bound here

You can just controll it with a boolean, so you only call unbind if bind has been made

public void doBindService()
{
    if (!mIsBound)
    {
        bindService(new Intent(this, DMusic.class), Scon, Context.BIND_AUTO_CREATE);
        mIsBound = true;
    }
}

public void doUnbindService()
{
    if (mIsBound)
    {
        unbindService(Scon);
        mIsBound = false;
    }
}

If you only want to unbind it if it has been connected

public ServiceConnection Scon = new ServiceConnection() {

    public void onServiceConnected(ComponentName name, IBinder binder)
    {
        mServ = ((DMusic.ServiceBinder) binder).getService();
        mIsBound = true;
    }

    public void onServiceDisconnected(ComponentName name)
    {
        mServ = null;
    }
};

Inserting a text where cursor is using Javascript/jquery

The accepted answer didn't work for me on Internet Explorer 9. I checked it and the browser detection was not working properly, it detected ff (firefox) when i was at Internet Explorer.

I just did this change:

if ($.browser.msie) 

Instead of:

if (br == "ie") { 

The resulting code is this one:

function insertAtCaret(areaId,text) {
    var txtarea = document.getElementById(areaId);
    var scrollPos = txtarea.scrollTop;
    var strPos = 0;
    var br = ((txtarea.selectionStart || txtarea.selectionStart == '0') ? 
        "ff" : (document.selection ? "ie" : false ) );

    if ($.browser.msie) { 
        txtarea.focus();
        var range = document.selection.createRange();
        range.moveStart ('character', -txtarea.value.length);
        strPos = range.text.length;
    }
    else if (br == "ff") strPos = txtarea.selectionStart;

    var front = (txtarea.value).substring(0,strPos);  
    var back = (txtarea.value).substring(strPos,txtarea.value.length); 
    txtarea.value=front+text+back;
    strPos = strPos + text.length;
    if (br == "ie") { 
        txtarea.focus();
        var range = document.selection.createRange();
        range.moveStart ('character', -txtarea.value.length);
        range.moveStart ('character', strPos);
        range.moveEnd ('character', 0);
        range.select();
    }
    else if (br == "ff") {
        txtarea.selectionStart = strPos;
        txtarea.selectionEnd = strPos;
        txtarea.focus();
    }
    txtarea.scrollTop = scrollPos;
}

How to declare a type as nullable in TypeScript?

All fields in JavaScript (and in TypeScript) can have the value null or undefined.

You can make the field optional which is different from nullable.

interface Employee1 {
    name: string;
    salary: number;
}

var a: Employee1 = { name: 'Bob', salary: 40000 }; // OK
var b: Employee1 = { name: 'Bob' }; // Not OK, you must have 'salary'
var c: Employee1 = { name: 'Bob', salary: undefined }; // OK
var d: Employee1 = { name: null, salary: undefined }; // OK

// OK
class SomeEmployeeA implements Employee1 {
    public name = 'Bob';
    public salary = 40000;
}

// Not OK: Must have 'salary'
class SomeEmployeeB implements Employee1 {
    public name: string;
}

Compare with:

interface Employee2 {
    name: string;
    salary?: number;
}

var a: Employee2 = { name: 'Bob', salary: 40000 }; // OK
var b: Employee2 = { name: 'Bob' }; // OK
var c: Employee2 = { name: 'Bob', salary: undefined }; // OK
var d: Employee2 = { name: null, salary: 'bob' }; // Not OK, salary must be a number

// OK, but doesn't make too much sense
class SomeEmployeeA implements Employee2 {
    public name = 'Bob';
}

How to add a custom CA Root certificate to the CA Store used by pip in Windows?

Run: python -c "import ssl; print(ssl.get_default_verify_paths())" to check the current paths which are used to verify the certificate. Add your company's root certificate to one of those.

The path openssl_capath_env points to the environment variable: SSL_CERT_DIR.

If SSL_CERT_DIR doesn't exist, you will need to create it and point it to a valid folder within your filesystem. You can then add your certificate to this folder to use it.

Should I Dispose() DataSet and DataTable?

This is the right way to properly Dispose the DataTable.

private DataTable CreateSchema_Table()
{
    DataTable td = null;
    try
    {
        td = new DataTable();
        //use table DataTable here
        
        return td.Copy();
    }
    catch {  }
    finally
    {
        if (td != null)
        {
            td.Constraints.Clear();
            td.Clear();
            td.Dispose();
            td = null;
        }
    }
}

The SELECT permission was denied on the object 'sysobjects', database 'mssqlsystemresource', schema 'sys'

In my case, simply giving the user permissions on the database fixed it.

So Right click on the database -> Click Properties -> [left hand menu] Click Permissions -> and scroll down to Backup database -> Tick "Grant"

Git add all files modified, deleted, and untracked?

git add --all or git add -A or git add -A . Stages All

git add . Stages New & Modified But Without Deleted

git add -u Stages Modified & Deleted But Without New

git commit -a Means git add -u And git commit -m "message"

After writing this command follow these steps:-

  1. press i
  2. write your message
  3. press esc
  4. press :wq
  5. press enter

git add <list of files> add specific file

git add *.txt add all the txt files in current directory

git add docs/*/txt add all txt files in docs directory

git add docs/ add all files in docs directory

git add "*.txt" or git add '*.txt' add all the files in the whole project

Why do we need to use flatMap?

Simple:

[1,2,3].map(x => [x, x * 10])
// [[1, 10], [2, 20], [3, 30]]

[1,2,3].flatMap(x => [x, x * 10])
// [1, 10, 2, 20, 3, 30]]

Pandas column of lists, create a row for each list element

lst_col = 'samples'

r = pd.DataFrame({
      col:np.repeat(df[col].values, df[lst_col].str.len())
      for col in df.columns.drop(lst_col)}
    ).assign(**{lst_col:np.concatenate(df[lst_col].values)})[df.columns]

Result:

In [103]: r
Out[103]:
    samples  subject  trial_num
0      0.10        1          1
1     -0.20        1          1
2      0.05        1          1
3      0.25        1          2
4      1.32        1          2
5     -0.17        1          2
6      0.64        1          3
7     -0.22        1          3
8     -0.71        1          3
9     -0.03        2          1
10    -0.65        2          1
11     0.76        2          1
12     1.77        2          2
13     0.89        2          2
14     0.65        2          2
15    -0.98        2          3
16     0.65        2          3
17    -0.30        2          3

PS here you may find a bit more generic solution


UPDATE: some explanations: IMO the easiest way to understand this code is to try to execute it step-by-step:

in the following line we are repeating values in one column N times where N - is the length of the corresponding list:

In [10]: np.repeat(df['trial_num'].values, df[lst_col].str.len())
Out[10]: array([1, 1, 1, 2, 2, 2, 3, 3, 3, 1, 1, 1, 2, 2, 2, 3, 3, 3], dtype=int64)

this can be generalized for all columns, containing scalar values:

In [11]: pd.DataFrame({
    ...:           col:np.repeat(df[col].values, df[lst_col].str.len())
    ...:           for col in df.columns.drop(lst_col)}
    ...:         )
Out[11]:
    trial_num  subject
0           1        1
1           1        1
2           1        1
3           2        1
4           2        1
5           2        1
6           3        1
..        ...      ...
11          1        2
12          2        2
13          2        2
14          2        2
15          3        2
16          3        2
17          3        2

[18 rows x 2 columns]

using np.concatenate() we can flatten all values in the list column (samples) and get a 1D vector:

In [12]: np.concatenate(df[lst_col].values)
Out[12]: array([-1.04, -0.58, -1.32,  0.82, -0.59, -0.34,  0.25,  2.09,  0.12,  0.83, -0.88,  0.68,  0.55, -0.56,  0.65, -0.04,  0.36, -0.31])

putting all this together:

In [13]: pd.DataFrame({
    ...:           col:np.repeat(df[col].values, df[lst_col].str.len())
    ...:           for col in df.columns.drop(lst_col)}
    ...:         ).assign(**{lst_col:np.concatenate(df[lst_col].values)})
Out[13]:
    trial_num  subject  samples
0           1        1    -1.04
1           1        1    -0.58
2           1        1    -1.32
3           2        1     0.82
4           2        1    -0.59
5           2        1    -0.34
6           3        1     0.25
..        ...      ...      ...
11          1        2     0.68
12          2        2     0.55
13          2        2    -0.56
14          2        2     0.65
15          3        2    -0.04
16          3        2     0.36
17          3        2    -0.31

[18 rows x 3 columns]

using pd.DataFrame()[df.columns] will guarantee that we are selecting columns in the original order...

How can I use the HTML5 canvas element in IE?

You could use the newly released Chrome Frame plugin for IE, but it requires that the HTML 5 website includes the special meta tag that enables the plugin.

http://code.google.com/chrome/chromeframe/

Chrome Frame seems to use Explore Canvas (excanvas.js).

How to disable XDebug

Inspired by PHPStorm right click on a file -> debug -> ...

www-data@3bd1617787db:~/symfony$ 
php 
-dxdebug.remote_enable=0 
-dxdebug.remote_autostart=0 
-dxdebug.default_enable=0 
-dxdebug.profiler_enable=0 
test.php

the important stuff is -dxdebug.remote_enable=0 -dxdebug.default_enable=0

What is the size of a pointer?

The size of a pointer is the size required by your system to hold a unique memory address (since a pointer just holds the address it points to)