Programs & Examples On #Unattended processing

Executing multi-line statements in the one-line command-line?

there is one more option, sys.stdout.write returns None, which keep the list empty

cat somefile.log|python -c "import sys;[line for line in sys.stdin if sys.stdout.write(line*2)]"

Scanner is skipping nextLine() after using next() or nextFoo()?

Use this code it will fix your problem.

System.out.println("Enter numerical value");    
int option;
option = input.nextInt(); // Read numerical value from input
input.nextLine();
System.out.println("Enter 1st string"); 
String string1 = input.nextLine(); // Read 1st string (this is skipped)
System.out.println("Enter 2nd string");
String string2 = input.nextLine(); // Read 2nd string (this appears right after reading numerical value)

HTTP requests and JSON parsing in Python

Try this:

import requests
import json

# Goole Maps API.
link = 'http://maps.googleapis.com/maps/api/directions/json?origin=Chicago,IL&destination=Los+Angeles,CA&waypoints=Joplin,MO|Oklahoma+City,OK&sensor=false'

# Request data from link as 'str'
data = requests.get(link).text

# convert 'str' to Json
data = json.loads(data)

# Now you can access Json 
for i in data['routes'][0]['legs'][0]['steps']:
    lattitude = i['start_location']['lat']
    longitude = i['start_location']['lng']
    print('{}, {}'.format(lattitude, longitude))

How to create nested directories using Mkdir in Golang?

This is one alternative for achieving the same but it avoids race condition caused by having two distinct "check ..and.. create" operations.

package main

import (
    "fmt"
    "os"
)

func main()  {
    if err := ensureDir("/test-dir"); err != nil {
        fmt.Println("Directory creation failed with error: " + err.Error())
        os.Exit(1)
    }
    // Proceed forward
}

func ensureDir(dirName string) error {

    err := os.MkdirAll(dirName, os.ModeDir)

    if err == nil || os.IsExist(err) {
        return nil
    } else {
        return err
    }
}

Is it possible to assign numeric value to an enum in Java?

Assuming that EXIT_CODE is referring to System . exit ( exit_code ) then you could do

enum ExitCode
{
      NORMAL_SHUTDOWN ( 0 ) , EMERGENCY_SHUTDOWN ( 10 ) , OUT_OF_MEMORY ( 20 ) , WHATEVER ( 30 ) ;

      private int value ;

      ExitCode ( int value )
      {
           this . value = value ;
      }

      public void exit ( )
      {
            System . exit ( value ) ;
      }
}

Then you can put the following at appropriate spots in your code

ExitCode . NORMAL_SHUTDOWN . exit ( ) '

How to re-create database for Entity Framework?

A possible very simple fix that worked for me. After deleting any database references and connections you find in server/serverobject explorer, right click the App_Data folder (didn't show any objects within the application for me) and select open. Once open put all the database/etc. files in a backup folder or if you have the guts just delete them. Run your application and it should recreate everything from scratch.

Increasing nesting function calls limit

Personally I would suggest this is an error as opposed to a setting that needs adjusting. In my code it was because I had a class that had the same name as a library within one of my controllers and it seemed to trip it up.

Output errors and see where this is being triggered.

How to convert a 3D point into 2D perspective projection?

I know it's an old topic but your illustration is not correct, the source code sets up the clip matrix correct.

[fov * aspectRatio][        0        ][        0              ][        0       ]
[        0        ][       fov       ][        0              ][        0       ]
[        0        ][        0        ][(far+near)/(far-near)  ][(2*near*far)/(near-far)]
[        0        ][        0        ][        1              ][        0       ]

some addition to your things:

This clip matrix works only if you are projecting on static 2D plane if you want to add camera movement and rotation:

viewMatrix = clipMatrix * cameraTranslationMatrix4x4 * cameraRotationMatrix4x4;

this lets you rotate the 2D plane and move it around..-

Woocommerce get products

<?php  
    $args = array(
        'post_type'      => 'product',
        'posts_per_page' => 10,
        'product_cat'    => 'hoodies'
    );

    $loop = new WP_Query( $args );

    while ( $loop->have_posts() ) : $loop->the_post();
        global $product;
        echo '<br /><a href="'.get_permalink().'">' . woocommerce_get_product_thumbnail().' '.get_the_title().'</a>';
    endwhile;

    wp_reset_query();
?>

This will list all product thumbnails and names along with their links to product page. change the category name and posts_per_page as per your requirement.

Make columns of equal width in <table>

Use following property same as table and its fully dynamic:

_x000D_
_x000D_
ul {_x000D_
    width: 100%;_x000D_
    display: table;_x000D_
    table-layout: fixed; /* optional, for equal spacing */_x000D_
    border-collapse: collapse;_x000D_
}_x000D_
li {_x000D_
    display: table-cell;_x000D_
    text-align: center;_x000D_
    border: 1px solid pink;_x000D_
    vertical-align: middle;_x000D_
}
_x000D_
<ul>_x000D_
  <li>foo<br>foo</li>_x000D_
  <li>barbarbarbarbar</li>_x000D_
  <li>baz klxjgkldjklg </li>_x000D_
  <li>baz</li>_x000D_
  <li>baz lds.jklklds</li>_x000D_
</ul>
_x000D_
_x000D_
_x000D_

May be its solve your issue.

Get dates from a week number in T-SQL

This works for me:

select 
    convert(varchar(50), dateadd(dd, - datepart(dw, DATECOL) + 1, DATECOL), 101),
    convert(varchar(50), dateadd(dd, - datepart(dw, DATECOL) + 7, DATECOL), 101)

Maximum value of maxRequestLength?

As per MSDN the default value is 4096 KB (4 MB).

UPDATE

As for the Maximum, since it is an int data type, then theoretically you can go up to 2,147,483,647. Also I wanted to make sure that you are aware that IIS 7 uses maxAllowedContentLength for specifying file upload size. By default it is set to 30000000 around 30MB and being an uint, it should theoretically allow a max of 4,294,967,295

How to insert data to MySQL having auto incremented primary key?

Check out this post

According to it

No value was specified for the AUTO_INCREMENT column, so MySQL assigned sequence numbers automatically. You can also explicitly assign NULL or 0 to the column to generate sequence numbers.

How can I recover a lost commit in Git?

git reflog is your friend. Find the commit that you want to be on in that list and you can reset to it (for example:git reset --hard e870e41).

(If you didn't commit your changes... you might be in trouble - commit early, and commit often!)

How to make git mark a deleted and a new file as a file move?

Do the move and the modify in separate commits.

VBA Excel sort range by specific column

Or this:

Range("A2", Range("D" & Rows.Count).End(xlUp).Address).Sort Key1:=[b3], _
    Order1:=xlAscending, Header:=xlYes

How to use if-else logic in Java 8 stream forEach

The problem by using stream().forEach(..) with a call to add or put inside the forEach (so you mutate the external myMap or myList instance) is that you can run easily into concurrency issues if someone turns the stream in parallel and the collection you are modifying is not thread safe.

One approach you can take is to first partition the entries in the original map. Once you have that, grab the corresponding list of entries and collect them in the appropriate map and list.

Map<Boolean, List<Map.Entry<K, V>>> partitions =
    animalMap.entrySet()
             .stream()
             .collect(partitioningBy(e -> e.getValue() == null));

Map<K, V> myMap = 
    partitions.get(false)
              .stream()
              .collect(toMap(Map.Entry::getKey, Map.Entry::getValue));

List<K> myList =
    partitions.get(true)
              .stream()
              .map(Map.Entry::getKey) 
              .collect(toList());

... or if you want to do it in one pass, implement a custom collector (assuming a Tuple2<E1, E2> class exists, you can create your own), e.g:

public static <K,V> Collector<Map.Entry<K, V>, ?, Tuple2<Map<K, V>, List<K>>> customCollector() {
    return Collector.of(
            () -> new Tuple2<>(new HashMap<>(), new ArrayList<>()),
            (pair, entry) -> {
                if(entry.getValue() == null) {
                    pair._2.add(entry.getKey());
                } else {
                    pair._1.put(entry.getKey(), entry.getValue());
                }
            },
            (p1, p2) -> {
                p1._1.putAll(p2._1);
                p1._2.addAll(p2._2);
                return p1;
            });
}

with its usage:

Tuple2<Map<K, V>, List<K>> pair = 
    animalMap.entrySet().parallelStream().collect(customCollector());

You can tune it more if you want, for example by providing a predicate as parameter.

What's the difference between "app.render" and "res.render" in express.js?

use app.render in scenarios where you need to render a view but not send it to a client via http. html emails springs to mind.

How can I properly use a PDO object for a parameterized SELECT query

Method 1:USE PDO query method

$stmt = $db->query('SELECT id FROM Employee where name ="'.$name.'"');
$results = $stmt->fetchAll(PDO::FETCH_ASSOC);

Getting Row Count

$stmt = $db->query('SELECT id FROM Employee where name ="'.$name.'"');
$row_count = $stmt->rowCount();
echo $row_count.' rows selected';

Method 2: Statements With Parameters

$stmt = $db->prepare("SELECT id FROM Employee WHERE name=?");
$stmt->execute(array($name));
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

Method 3:Bind parameters

$stmt = $db->prepare("SELECT id FROM Employee WHERE name=?");
$stmt->bindValue(1, $name, PDO::PARAM_STR);
$stmt->execute();
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

**bind with named parameters**
$stmt = $db->prepare("SELECT id FROM Employee WHERE name=:name");
$stmt->bindValue(':name', $name, PDO::PARAM_STR);
$stmt->execute();
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

or
$stmt = $db->prepare("SELECT id FROM Employee WHERE name=:name");
$stmt->execute(array(':name' => $name));
$rows = $stmt->fetchAll(PDO::FETCH_ASSOC);

Want to know more look at this link

Python: Writing to and Reading from serial port

a piece of code who work with python to read rs232 just in case somedoby else need it

ser = serial.Serial('/dev/tty.usbserial', 9600, timeout=0.5)
ser.write('*99C\r\n')
time.sleep(0.1)
ser.close()

Find distance between two points on map using Google Map API V2

you can use this function. I have used it in my project.

public String getDistance(LatLng my_latlong, LatLng frnd_latlong) {
    Location l1 = new Location("One");
    l1.setLatitude(my_latlong.latitude);
    l1.setLongitude(my_latlong.longitude);

    Location l2 = new Location("Two");
    l2.setLatitude(frnd_latlong.latitude);
    l2.setLongitude(frnd_latlong.longitude);

    float distance = l1.distanceTo(l2);
    String dist = distance + " M";

    if (distance > 1000.0f) {
        distance = distance / 1000.0f;
        dist = distance + " KM";
    }
    return dist;
}

How to add directory to classpath in an application run profile in IntelliJ IDEA?

You need not specify the classes folder. Intellij should be able to load it. You will get this error if "Project Compiler output" is blank.

Just make sure that below value is set: Project Settings -> Project -> Project Compiler output to your projectDir/out folder

Creating lowpass filter in SciPy - understanding methods and units

A few comments:

  • The Nyquist frequency is half the sampling rate.
  • You are working with regularly sampled data, so you want a digital filter, not an analog filter. This means you should not use analog=True in the call to butter, and you should use scipy.signal.freqz (not freqs) to generate the frequency response.
  • One goal of those short utility functions is to allow you to leave all your frequencies expressed in Hz. You shouldn't have to convert to rad/sec. As long as you express your frequencies with consistent units, the scaling in the utility functions takes care of the normalization for you.

Here's my modified version of your script, followed by the plot that it generates.

import numpy as np
from scipy.signal import butter, lfilter, freqz
import matplotlib.pyplot as plt


def butter_lowpass(cutoff, fs, order=5):
    nyq = 0.5 * fs
    normal_cutoff = cutoff / nyq
    b, a = butter(order, normal_cutoff, btype='low', analog=False)
    return b, a

def butter_lowpass_filter(data, cutoff, fs, order=5):
    b, a = butter_lowpass(cutoff, fs, order=order)
    y = lfilter(b, a, data)
    return y


# Filter requirements.
order = 6
fs = 30.0       # sample rate, Hz
cutoff = 3.667  # desired cutoff frequency of the filter, Hz

# Get the filter coefficients so we can check its frequency response.
b, a = butter_lowpass(cutoff, fs, order)

# Plot the frequency response.
w, h = freqz(b, a, worN=8000)
plt.subplot(2, 1, 1)
plt.plot(0.5*fs*w/np.pi, np.abs(h), 'b')
plt.plot(cutoff, 0.5*np.sqrt(2), 'ko')
plt.axvline(cutoff, color='k')
plt.xlim(0, 0.5*fs)
plt.title("Lowpass Filter Frequency Response")
plt.xlabel('Frequency [Hz]')
plt.grid()


# Demonstrate the use of the filter.
# First make some data to be filtered.
T = 5.0         # seconds
n = int(T * fs) # total number of samples
t = np.linspace(0, T, n, endpoint=False)
# "Noisy" data.  We want to recover the 1.2 Hz signal from this.
data = np.sin(1.2*2*np.pi*t) + 1.5*np.cos(9*2*np.pi*t) + 0.5*np.sin(12.0*2*np.pi*t)

# Filter the data, and plot both the original and filtered signals.
y = butter_lowpass_filter(data, cutoff, fs, order)

plt.subplot(2, 1, 2)
plt.plot(t, data, 'b-', label='data')
plt.plot(t, y, 'g-', linewidth=2, label='filtered data')
plt.xlabel('Time [sec]')
plt.grid()
plt.legend()

plt.subplots_adjust(hspace=0.35)
plt.show()

lowpass example

Calling a function within a Class method?

To call any method of an object instantiated from a class (with statement new), you need to "point" to it. From the outside you just use the resource created by the new statement. Inside any object PHP created by new, saves the same resource into the $this variable. So, inside a class you MUST point to the method by $this. In your class, to call smallTest from inside the class, you must tell PHP which of all the objects created by the new statement you want to execute, just write:

$this->smallTest();

I need to convert an int variable to double

Either use casting as others have already said, or multiply one of the int variables by 1.0:

double firstSolution = ((1.0* b1 * a22 - b2 * a12) / (a11 * a22 - a12 * a21));

How to find where gem files are installed

After installing the gems, if you want to know where a particular gem is. Try typing:

 gem list

You will be able to see the list of gems you have installed. Now use bundle show and name the gem you want to know the path for, like this:

 bundle show <gemName>

Or (as of younger versions of bundler):

 bundle info <gemName>

load jquery after the page is fully loaded

If you're trying to avoid loading jquery until your content has been loaded, the best way is to simply put the reference to it in the bottom of your page, like many other answers have said.

General tips on Jquery usage:

  1. Use a CDN. This way, your site can use the cached version a user likely has on their computer. The // at the beginning allows it to be called (and use the same resource) whether it's http or https. Example:

    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>

Using a CDN has a couple of big benefits: it makes it more likely that users have it cached from another site, so there will be no download (and no render-blocking). Further, CDNs use the closest, fastest connection available, meaning that if they do need to load it, it will probably be faster than connecting to your server. More info from Google.

  1. Put scripts at the bottom. Move as much of your js to the bottom of the page as possible. I use php to include a file with all my JS resources below the footer.

  2. If you're using a template system, you may need to have javascript spread throughout the html output. If you're using jquery in scripts that get called as the page renders, this will cause errors. To have your scripts wait until jquery is loaded, put them into

    window.onload() = function () { //... your js that isn't called by user interaction ... }

This will prevent errors but still run before user interaction and without timers.

Of course, if jquery is cached, it won't matter too much where you put it, except to page speed tools that will tell you you're blocking rendering.

Calculating powers of integers

When it's power of 2. Take in mind, that you can use simple and fast shift expression 1 << exponent

example:

22 = 1 << 2 = (int) Math.pow(2, 2)
210 = 1 << 10 = (int) Math.pow(2, 10)

For larger exponents (over 31) use long instead

232 = 1L << 32 = (long) Math.pow(2, 32)

btw. in Kotlin you have shl instead of << so

(java) 1L << 32 = 1L shl 32 (kotlin)

What ports does RabbitMQ use?

PORT 4369: Erlang makes use of a Port Mapper Daemon (epmd) for resolution of node names in a cluster. Nodes must be able to reach each other and the port mapper daemon for clustering to work.

PORT 35197 set by inet_dist_listen_min/max Firewalls must permit traffic in this range to pass between clustered nodes

RabbitMQ Management console:

  • PORT 15672 for RabbitMQ version 3.x
  • PORT 55672 for RabbitMQ pre 3.x

PORT 5672 RabbitMQ main port.

For a cluster of nodes, they must be open to each other on 35197, 4369 and 5672.

For any servers that want to use the message queue, only 5672 is required.

How to call a JavaScript function within an HTML body

Try wrapping the createtable(); statement in a <script> tag:

<table>
        <tr>
            <th>Balance</th>
            <th>Fee</th>

        </tr>
        <script>createtable();</script>
</table>

I would avoid using document.write() and use the DOM if I were you though.

How do I target only Internet Explorer 10 for certain situations like Internet Explorer-specific CSS or Internet Explorer-specific JavaScript code?

Here is how I do custom CSS for Internet Explorer:

In my JavaScript file:

function isIE () {
      var myNav = navigator.userAgent.toLowerCase();
      return (myNav.indexOf('msie') != -1) ? parseInt(myNav.split('msie')[1]) : false;
}

jQuery(document).ready(function(){
    if(var_isIE){
            if(var_isIE == 10){
                jQuery("html").addClass("ie10");
            }
            if(var_isIE == 8){
                jQuery("html").addClass("ie8");
                // you can also call here some function to disable things that 
                //are not supported in IE, or override browser default styles.
            }
        }
    });

And then in my CSS file, y define each different style:

.ie10 .some-class span{
    .......
}
.ie8 .some-class span{
    .......
}

Testing for empty or nil-value string

The second clause does not need a !variable.nil? check—if evaluation reaches that point, variable.nil is guaranteed to be false (because of short-circuiting).

This should be sufficient:

variable = id if variable.nil? || variable.empty?

If you're working with Ruby on Rails, Object.blank? solves this exact problem:

An object is blank if it’s false, empty, or a whitespace string. For example, "", " ", nil, [], and {} are all blank.

jQuery Remove string from string

To add on nathan gonzalez answer, please note you need to assign the replaced object after calling replace function since it is not a mutator function:

myString = myString.replace('username1','');

How do I rename a local Git branch?

The answers so far have been correct, but here is some additional information:

One can safely rename a branch with '-m' (move), but one has to be careful with '-M', because it forces the rename, even if there is an existing branch with the same name already. Here is the excerpt from the 'git-branch' man page:

With a -m or -M option, <oldbranch> will be renamed to <newbranch>. If <oldbranch> had a corresponding reflog, it is renamed to match <newbranch>, and a reflog entry is created to remember the branch renaming. If <newbranch> exists, -M must be used to force the rename to happen.

How do I force a favicon refresh?

Also make sure you put the full image URL not just its relative path:

http://www.example.com/images/favicon.ico

And not:

images/favicon.ico

How do I make a dotted/dashed line in Android?

I have created dashed dotted line for EditText. Here you go. Create your new xml. e.g dashed_border.xml Code here:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item
    android:bottom="1dp"
    android:left="-2dp"
    android:right="-2dp"
    android:top="-2dp">
    <shape android:shape="rectangle">
        <stroke
            android:width="2dp"
            android:color="#000000"
            android:dashGap="3dp"
            android:dashWidth="1dp" />

        <solid android:color="#00FFFFFF" />

        <padding
            android:bottom="10dp"
            android:left="10dp"
            android:right="10dp"
            android:top="10dp" />
    </shape>
</item></layer-list>

And use your new xml file in your EditText for example:

<EditText
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@drawable/dashed_border"/>

Cheers! :)

Install sbt on ubuntu

No command sbt found

It's saying that sbt is not on your path. Try to run ./sbt from ~/bin/sbt/bin or wherever the sbt executable is to verify that it runs correctly. Also check that you have execute permissions on the sbt executable. If this works , then add ~/bin/sbt/bin to your path and sbt should run from anywhere.

See this question about adding a directory to your path.

To verify the path is set correctly use the which command on LINUX. The output will look something like this:

$ which sbt
/usr/bin/sbt

Lastly, to verify sbt is working try running sbt -help or likewise. The output with -help will look something like this:

$ sbt -help
Usage: sbt [options]

  -h | -help         print this message
  ...

Select top 1 result using JPA

Use a native SQL query by specifying a @NamedNativeQuery annotation on the entity class, or by using the EntityManager.createNativeQuery method. You will need to specify the type of the ResultSet using an appropriate class, or use a ResultSet mapping.

What is a stored procedure?

A stored procedure is used to retrieve data, modify data, and delete data in database table. You don't need to write a whole SQL command each time you want to insert, update or delete data in an SQL database.

Git push failed, "Non-fast forward updates were rejected"

(One) Solution for Netbeans 7.1: Try a pull. This will probably also fail. Now have a look into the logs (they are usually shown now in the IDE). There's one/more line saying:

"Pull failed due to this file:"

Search that file, delete it (make a backup before). Usually it's a .gitignore file, so you will not delete code. Redo the push. Everything should work fine now.

Extracting columns from text file with different delimiters in Linux

If the command should work with both tabs and spaces as the delimiter I would use awk:

awk '{print $100,$101,$102,$103,$104,$105}' myfile > outfile

As long as you just need to specify 5 fields it is imo ok to just type them, for longer ranges you can use a for loop:

awk '{for(i=100;i<=105;i++)print $i}' myfile > outfile

If you want to use cut, you need to use the -f option:

cut -f100-105 myfile > outfile

If the field delimiter is different from TAB you need to specify it using -d:

cut -d' ' -f100-105 myfile > outfile

Check the man page for more info on the cut command.

Read user input inside a loop

You can redirect the regular stdin through unit 3 to keep the get it inside the pipeline:

{ cat notify-finished | while read line; do
    read -u 3 input
    echo "$input"
done; } 3<&0

BTW, if you really are using cat this way, replace it with a redirect and things become even easier:

while read line; do
    read -u 3 input
    echo "$input"
done 3<&0 <notify-finished

Or, you can swap stdin and unit 3 in that version -- read the file with unit 3, and just leave stdin alone:

while read line <&3; do
    # read & use stdin normally inside the loop
    read input
    echo "$input"
done 3<notify-finished

How to check if string contains Latin characters only?

You can use regex:

/[a-z]/i.test(str);

The i makes the regex case-insensitive. You could also do:

/[a-z]/.test(str.toLowerCase());

How do I run a Python script on my web server?

Very simply, you can rename your Python script to "pythonscript.cgi". Post that in your cgi-bin directory, add the appropriate permissions and browse to it.

This is a great link you can start with.

Here's another good one.

Hope that helps.


EDIT (09/12/2015): The second link has long been removed. Replaced it with one that provides information referenced from the original.

Find all matches in workbook using Excel VBA

Based on the idea of B Hart's answer, here's my version of a function that searches for a value in a range, and returns all found ranges (cells):

Function FindAll(ByVal rng As Range, ByVal searchTxt As String) As Range
    Dim foundCell As Range
    Dim firstAddress
    Dim rResult As Range
    With rng
        Set foundCell = .Find(What:=searchTxt, _
                              After:=.Cells(.Cells.Count), _
                              LookIn:=xlValues, _
                              LookAt:=xlWhole, _
                              SearchOrder:=xlByRows, _
                              SearchDirection:=xlNext, _
                              MatchCase:=False)
        If Not foundCell Is Nothing Then
            firstAddress = foundCell.Address
            Do
                If rResult Is Nothing Then
                    Set rResult = foundCell
                Else
                    Set rResult = Union(rResult, foundCell)
                End If
                Set foundCell = .FindNext(foundCell)
            Loop While Not foundCell Is Nothing And foundCell.Address <> firstAddress
        End If
    End With

    Set FindAll = rResult
End Function

To search for a value in the whole workbook:

Dim wSh As Worksheet
Dim foundCells As Range
For Each wSh In ThisWorkbook.Worksheets
    Set foundCells = FindAll(wSh.UsedRange, "YourSearchString")
    If Not foundCells Is Nothing Then
        Debug.Print ("Results in sheet '" & wSh.Name & "':")
        Dim cell As Range
        For Each cell In foundCells
            Debug.Print ("The value has been found in cell: " & cell.Address)
        Next
    End If
Next

Java 8: merge lists with stream API

In Java 8 we can use stream List1.stream().collect(Collectors.toList()).addAll(List2); Another option List1.addAll(List2)

Java reading a file into an ArrayList?

Simplest form I ever found is...

List<String> lines = Files.readAllLines(Paths.get("/path/to/file.txt"));

permission denied - php unlink

in addition to all the answers that other friends have , if somebody who is looking this post is looking for a way to delete a "Folder" not a "file" , should take care that Folders must delete by php rmdir() function and if u want to delete a "Folder" by unlink() , u will encounter with a wrong Warning message that says "permission denied"

however u can make folders & files by mkdir() but the way u delete folders (rmdir()) is different from the way you delete files(unlink())

eventually as a fact:

in many programming languages, any permission related error may not directly means an actual permission issue

for example, if you want to readSync a file that doesn't exist with node fs module you will encounter a wrong EPERM error

DataAdapter.Fill(Dataset)

You need to do this:

OleDbConnection connection = new OleDbConnection(
    "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=Inventar.accdb");
DataSet DS = new DataSet();
connection.Open();

string query = 
    @"SELECT tbl_Computer.*,  tbl_Besitzer.*
    FROM tbl_Computer 
    INNER JOIN tbl_Besitzer ON tbl_Computer.FK_Benutzer = tbl_Besitzer.ID 
    WHERE (((tbl_Besitzer.Vorname)='ma'))";
OleDbDataAdapter DBAdapter = new OleDbDataAdapter();
DBAdapter.SelectCommand = new OleDbCommand(query, connection); 
DBAdapter.Fill(DS);

By the way, what is this DataSet1? This should be "DataSet".

Make a Bash alias that takes a parameter?

Bash alias does not directly accept parameters. You will have to create a function.

alias does not accept parameters but a function can be called just like an alias. For example:

myfunction() {
    #do things with parameters like $1 such as
    mv "$1" "$1.bak"
    cp "$2" "$1"
}


myfunction old.conf new.conf #calls `myfunction`

By the way, Bash functions defined in your .bashrc and other files are available as commands within your shell. So for instance you can call the earlier function like this

$ myfunction original.conf my.conf

HTML iframe - disable scroll

Set all the content to:

#yourContent{
 width:100%;
height:100%;  // in you csss
}

The thing is that the iframe scroll is set by the content NOT by the iframe by itself.

set the content to 100% in the interior with CSS and the desired for the iframe in HTML

understanding private setters

I don't understand the need of having private setters which started with C# 2.

Use case example:

I have an instance of an application object 'UserInfo' that contains a property SessionTokenIDV1 that I don't wish to expose to consumers of my class.

I also need the ability to set that value from my class.

My solution was to encapsulate the property as shown and make the setter private so that I can set the value of the session token without allowing instantiating code to also set it (or even see it in my case)

public class UserInfo
{
   public String SessionTokenIDV1 { get; set; }

}


public class Example
{
  // Private vars
  private UserInfo _userInfo = new UserInfo();

  public string SessionValidV1
  {
    get { return ((_userInfo.SessionTokenIDV1 != null) && (_userInfo.SessionTokenIDV1.Length > 0)) ? "set" : "unset"; }
    private set { _userInfo.SessionTokenIDV1 = value; }
  }
}

Edit: Fixed Code Tag Edit: Example had errors which have been corrected

oracle varchar to number

select to_number(exception_value) from exception where to_number(exception_value) = 105

"A referral was returned from the server" exception when accessing AD from C#

This is the answer for the question.Reason for the cause is my LDAP string was wrong.

    try
    {
        string adServer = ConfigurationManager.AppSettings["Server"];
        string adDomain = ConfigurationManager.AppSettings["Domain"];
        string adUsername = ConfigurationManager.AppSettings["AdiminUsername"];
        string password = ConfigurationManager.AppSettings["Password"];
        string[] dc = adDomain.Split('.');
        string dcAdDomain = string.Empty;

        foreach (string item in dc)
        {
            if (dc[dc.Length - 1].Equals(item))
                dcAdDomain = dcAdDomain + "DC=" + item;
            else
                dcAdDomain = dcAdDomain + "DC=" + item + ",";
        }

        DirectoryEntry de = new DirectoryEntry("LDAP://" + adServer + "/CN=Users," + dcAdDomain, adUsername, password);

        DirectorySearcher ds = new DirectorySearcher(de);

        ds.SearchScope = SearchScope.Subtree;

        ds.Filter = "(&(objectClass=User)(sAMAccountName=" + username + "))";

        if (ds.FindOne() != null)
            return true;
    }
    catch (Exception ex)
    {
        ExLog(ex);
    }
    return false;

AES Encryption for an NSString on the iPhone

I waited a bit on @QuinnTaylor to update his answer, but since he didn't, here's the answer a bit more clearly and in a way that it will load on XCode7 (and perhaps greater). I used this in a Cocoa application, but it likely will work okay with an iOS application as well. Has no ARC errors.

Paste before any @implementation section in your AppDelegate.m or AppDelegate.mm file.

#import <CommonCrypto/CommonCryptor.h>

@implementation NSData (AES256)

- (NSData *)AES256EncryptWithKey:(NSString *)key {
    // 'key' should be 32 bytes for AES256, will be null-padded otherwise
    char keyPtr[kCCKeySizeAES256+1]; // room for terminator (unused)
    bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding)

    // fetch key data
    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];

    NSUInteger dataLength = [self length];

    //See the doc: For block ciphers, the output size will always be less than or 
    //equal to the input size plus the size of one block.
    //That's why we need to add the size of one block here
    size_t bufferSize = dataLength + kCCBlockSizeAES128;
    void *buffer = malloc(bufferSize);

    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
                                     keyPtr, kCCKeySizeAES256,
                                     NULL /* initialization vector (optional) */,
                                     [self bytes], dataLength, /* input */
                                     buffer, bufferSize, /* output */
                                     &numBytesEncrypted);
    if (cryptStatus == kCCSuccess) {
        //the returned NSData takes ownership of the buffer and will free it on deallocation
        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
    }

    free(buffer); //free the buffer;
    return nil;
}

- (NSData *)AES256DecryptWithKey:(NSString *)key {
    // 'key' should be 32 bytes for AES256, will be null-padded otherwise
    char keyPtr[kCCKeySizeAES256+1]; // room for terminator (unused)
    bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding)

    // fetch key data
    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];

    NSUInteger dataLength = [self length];

    //See the doc: For block ciphers, the output size will always be less than or 
    //equal to the input size plus the size of one block.
    //That's why we need to add the size of one block here
    size_t bufferSize = dataLength + kCCBlockSizeAES128;
    void *buffer = malloc(bufferSize);

    size_t numBytesDecrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding,
                                     keyPtr, kCCKeySizeAES256,
                                     NULL /* initialization vector (optional) */,
                                     [self bytes], dataLength, /* input */
                                     buffer, bufferSize, /* output */
                                     &numBytesDecrypted);

    if (cryptStatus == kCCSuccess) {
        //the returned NSData takes ownership of the buffer and will free it on deallocation
        return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
    }

    free(buffer); //free the buffer;
    return nil;
}

@end

Paste these two functions in the @implementation class you desire. In my case, I chose @implementation AppDelegate in my AppDelegate.mm or AppDelegate.m file.

- (NSString *) encryptString:(NSString*)plaintext withKey:(NSString*)key {
    NSData *data = [[plaintext dataUsingEncoding:NSUTF8StringEncoding] AES256EncryptWithKey:key];
    return [data base64EncodedStringWithOptions:kNilOptions];
}

- (NSString *) decryptString:(NSString *)ciphertext withKey:(NSString*)key {
    NSData *data = [[NSData alloc] initWithBase64EncodedString:ciphertext options:kNilOptions];
    return [[NSString alloc] initWithData:[data AES256DecryptWithKey:key] encoding:NSUTF8StringEncoding];
}

Dynamically change color to lighter or darker by percentage CSS (Javascript)

If you need to brute force it for older browser compatibility, you can use Colllor to automatically select similar color variations.

Example (color: #a9dbb4):

enter image description here

How to declare and display a variable in Oracle

If you're talking about PL/SQL, you should put it in an anonymous block.

DECLARE
    v_text VARCHAR2(10); -- declare
BEGIN
    v_text := 'Hello';  --assign
    dbms_output.Put_line(v_text); --display
END; 

I do not understand how execlp() works in Linux

this prototype:

  int execlp(const char *file, const char *arg, ...);

Says that execlp ìs a variable argument function. It takes 2 const char *. The rest of the arguments, if any, are the additional arguments to hand over to program we want to run - also char * - all these are C strings (and the last argument must be a NULL pointer)

So, the file argument is the path name of an executable file to be executed. arg is the string we want to appear as argv[0] in the executable. By convention, argv[0] is just the file name of the executable, normally it's set to the same as file.

The ... are now the additional arguments to give to the executable.

Say you run this from a commandline/shell:

$ ls

That'd be execlp("ls", "ls", (char *)NULL); Or if you run

$ ls -l /

That'd be execlp("ls", "ls", "-l", "/", (char *)NULL);

So on to execlp("/bin/sh", ..., "ls -l /bin/??", ...);

Here you are going to the shell, /bin/sh , and you're giving the shell a command to execute. That command is "ls -l /bin/??". You can run that manually from a commandline/shell:

 $ ls -l /bin/??

Now, how do you run a shell and tell it to execute a command ? You open up the documentation/man page for your shell and read it.

What you want to run is:

$ /bin/sh -c "ls -l /bin/??"

This becomes

  execlp("/bin/sh","/bin/sh", "-c", "ls -l /bin/??", (char *)NULL);

Side note: The /bin/?? is doing pattern matching, this pattern matching is done by the shell, and it expands to all files under /bin/ with 2 characters. If you simply did

  execlp("ls","ls", "-l", "/bin/??", (char *)NULL);

Probably nothing would happen (unless there's a file actually named /bin/??) as there's no shell that interprets and expands /bin/??

Android Volley - BasicNetwork.performRequest: Unexpected response code 400

change

public static final String URL = "http://api-Location";

to

public static final String URL = "https://api-Location"

it's happen because i'm using 000webhostapp app

Ansible: Set variable to file content

You can use lookups in Ansible in order to get the contents of a file, e.g.

user_data: "{{ lookup('file', user_data_file) }}"

Caveat: This lookup will work with local files, not remote files.

Here's a complete example from the docs:

- hosts: all
  vars:
     contents: "{{ lookup('file', '/etc/foo.txt') }}"
  tasks:
     - debug: msg="the value of foo.txt is {{ contents }}"

Can not get a simple bootstrap modal to work

A simple way to use modals is with eModal!

Ex from github:

  1. Link to eModal.js <script src="//rawgit.com/saribe/eModal/master/dist/eModal.min.js"></script>
  2. use eModal to display a modal for alert, ajax, prompt or confirm

    // Display an alert modal with default title (Attention)
    eModal.alert('You shall not pass!');
    

What is the "right" JSON date format?

If you are using Kotlin then this will solve your problem. (MS Json format)

val dataString = "/Date(1586583441106)/"
val date = Date(Long.parseLong(dataString.substring(6, dataString.length - 2)))

How to change UIButton image in Swift

in Swift 4, (Xcode 9) example to turn picture of button to On or Off (btnRec):

var bRec:Bool = true

@IBOutlet weak var btnRec: UIButton!
@IBAction func btnRec(_ sender: Any) {
    bRec = !bRec
    if bRec {
        btnRec.setImage(UIImage(named: "MicOn.png"), for: .normal)
    } else {
        btnRec.setImage(UIImage(named: "MicOff.png"), for: .normal)
    }
}

Using a cursor with dynamic SQL in a stored procedure

Working with a non-relational database (IDMS anyone?) over an ODBC connection qualifies as one of those times where cursors and dynamic SQL seems the only route.

select * from a where a=1 and b in (1,2)

takes 45 minutes to respond while re-written to use keysets without the in clause will run in under 1 second:

select * from a where (a=1 and b=1)
union all
select * from a where (a=1 and b=2)

If the in statement for column B contains 1145 rows, using a cursor to create indidivudal statements and execute them as dynamic SQL is far faster than using the in clause. Silly hey?

And yes, there's no time in a relational database that cursor's should be used. I just can't believe I've come across an instance where a cursor loop is several magnitudes quicker.

How to predict input image using trained model in Keras?

If someone is still struggling to make predictions on images, here is the optimized code to load the saved model and make predictions:

# Modify 'test1.jpg' and 'test2.jpg' to the images you want to predict on

from keras.models import load_model
from keras.preprocessing import image
import numpy as np

# dimensions of our images
img_width, img_height = 320, 240

# load the model we saved
model = load_model('model.h5')
model.compile(loss='binary_crossentropy',
              optimizer='rmsprop',
              metrics=['accuracy'])

# predicting images
img = image.load_img('test1.jpg', target_size=(img_width, img_height))
x = image.img_to_array(img)
x = np.expand_dims(x, axis=0)

images = np.vstack([x])
classes = model.predict_classes(images, batch_size=10)
print classes

# predicting multiple images at once
img = image.load_img('test2.jpg', target_size=(img_width, img_height))
y = image.img_to_array(img)
y = np.expand_dims(y, axis=0)

# pass the list of multiple images np.vstack()
images = np.vstack([x, y])
classes = model.predict_classes(images, batch_size=10)

# print the classes, the images belong to
print classes
print classes[0]
print classes[0][0]

How to use onClick event on react Link component?

I don't believe this is a good pattern to use in general. Link will run your onClick event and then navigate to the route, so there will be a slight delay navigating to the new route. A better strategy is to navigate to the new route with the 'to' prop as you have done, and in the new component's componentDidMount() function you can fire your hello function or any other function. It will give you the same result, but with a much smoother transition between routes.

For context, I noticed this while updating my redux store with an onClick event on Link like you have here, and it caused a ~.3 second blank-white-screen delay before mounting the new route's component. There was no api call involved, so I was surprised the delay was so big. However, if you're just console logging 'hello' the delay might not be noticeable.

Getting Current time to display in Label. VB.net

Try This.....

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load    
    Timer1.Start()
End Sub

Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
    Label12.Text = TimeOfDay.ToString("h:mm:ss tt")
End Sub

How to git-svn clone the last n revisions from a Subversion repository?

You've already discovered the simplest way to specify a shallow clone in Git-SVN, by specifying the SVN revision number that you want to start your clone at ( -r$REV:HEAD).

For example: git svn clone -s -r1450:HEAD some/svn/repo

Git's data structure is based on pointers in a directed acyclic graph (DAG), which makes it trivial to walk back n commits. But in SVN ( and therefore in Git-SVN) you will have to find the revision number yourself.

How to represent the double quotes character (") in regex?

you need to use backslash before ". like \"

From the doc here you can see that

A character preceded by a backslash ( \ ) is an escape sequence and has special meaning to the compiler.

and " (double quote) is a escacpe sequence

When an escape sequence is encountered in a print statement, the compiler interprets it accordingly. For example, if you want to put quotes within quotes you must use the escape sequence, \", on the interior quotes. To print the sentence

She said "Hello!" to me.

you would write

System.out.println("She said \"Hello!\" to me.");

Extract hostname name from string

Try below code for exact domain name using regex,

String line = "http://www.youtube.com/watch?v=ClkQA2Lb_iE";

  String pattern3="([\\w\\W]\\.)+(.*)?(\\.[\\w]+)";

  Pattern r = Pattern.compile(pattern3);


  Matcher m = r.matcher(line);
  if (m.find( )) {

    System.out.println("Found value: " + m.group(2) );
  } else {
     System.out.println("NO MATCH");
  }

Genymotion, "Unable to load VirtualBox engine." on Mavericks. VBox is setup correctly

Update: Genymotion's 2.5.1 release (https://www.genymotion.com/#!/release-notes/251#251) seems to have fixed this issue. (thanks for the heads up @Roger!)


For those that may be stumbling upon this a bit later, I resolved this by installing VirtualBox 4.3.28 (https://www.virtualbox.org/wiki/Download_Old_Builds_4_3). The new 5.0.0 and 4.3.30 versions didn't work for me with Genymotion 2.5. None of the above solutions worked :(

It's also worth noting that at the time of writing, Genymotion's FAQ states the following:

However, for performance reasons, we recommend using version 4.3.12

New warnings in iOS 9: "all bitcode will be dropped"

Your library was compiled without bitcode, but the bitcode option is enabled in your project settings. Say NO to Enable Bitcode in your target Build Settings and the Library Build Settings to remove the warnings.

For those wondering if enabling bitcode is required:

For iOS apps, bitcode is the default, but optional. For watchOS and tvOS apps, bitcode is required. If you provide bitcode, all apps and frameworks in the app bundle (all targets in the project) need to include bitcode.

https://help.apple.com/xcode/mac/current/#/devbbdc5ce4f

Trust Anchor not found for Android SSL Connection

Use https://www.ssllabs.com/ssltest/ to test a domain.

The solution of Shihab Uddin in Kotlin.

import java.security.SecureRandom
import java.security.cert.X509Certificate
import javax.net.ssl.*
import javax.security.cert.CertificateException

object {

    val okHttpClient: OkHttpClient
    val gson: Gson
    val retrofit: Retrofit

    init {

        okHttpClient = getOkHttpBuilder()
            // Other parameters like connectTimeout(15, TimeUnit.SECONDS)
            .build()

        gson = GsonBuilder().setLenient().create()

        retrofit = Retrofit.Builder()
            .baseUrl(BASE_URL)
            .client(okHttpClient)
            .addConverterFactory(GsonConverterFactory.create(gson))
            .build()
    }

    fun getOkHttpBuilder(): OkHttpClient.Builder =
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            OkHttpClient().newBuilder()
        } else {
            // Workaround for the error "Caused by: com.android.org.bouncycastle.jce.exception.ExtCertPathValidatorException: Could not validate certificate: Certificate expired at".
            getUnsafeOkHttpClient()
        }

    private fun getUnsafeOkHttpClient(): OkHttpClient.Builder =
        try {
            // Create a trust manager that does not validate certificate chains
            val trustAllCerts: Array<TrustManager> = arrayOf(
                object : X509TrustManager {
                    @Throws(CertificateException::class)
                    override fun checkClientTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    @Throws(CertificateException::class)
                    override fun checkServerTrusted(chain: Array<X509Certificate?>?,
                                                    authType: String?) = Unit

                    override fun getAcceptedIssuers(): Array<X509Certificate> = arrayOf()
                }
            )
            // Install the all-trusting trust manager
            val sslContext: SSLContext = SSLContext.getInstance("SSL")
            sslContext.init(null, trustAllCerts, SecureRandom())
            // Create an ssl socket factory with our all-trusting manager
            val sslSocketFactory: SSLSocketFactory = sslContext.socketFactory
            val builder = OkHttpClient.Builder()
            builder.sslSocketFactory(sslSocketFactory,
                trustAllCerts[0] as X509TrustManager)
            builder.hostnameVerifier { _, _ -> true }
            builder
        } catch (e: Exception) {
            throw RuntimeException(e)
        }
}

The same error will also appear if you use Glide, images won't show. To overcome it see Glide - javax.net.ssl.SSLHandshakeException: java.security.cert.CertPathValidatorException: Trust anchor for certification path not found and How to set OkHttpClient for glide.

@GlideModule
class MyAppGlideModule : AppGlideModule() {

    val okHttpClient = Api.getOkHttpBuilder().build() // Api is the class written above.
    // It is better to create okHttpClient here and not use Api.okHttpClient,
    // because their settings may differ. For instance, it can use its own
    // `addInterceptor` and `addNetworkInterceptor` that can affect on a read JSON.


    override fun registerComponents(context: Context, glide: Glide, registry: Registry) {
        registry.replace(GlideUrl::class.java, InputStream::class.java,
            OkHttpUrlLoader.Factory(okHttpClient))
    }
}

build.gradle:

// Glide.
implementation 'com.github.bumptech.glide:glide:4.11.0'
implementation 'com.github.bumptech.glide:okhttp3-integration:4.11.0'
kapt 'com.github.bumptech.glide:compiler:4.11.0'

Is there a way since (iOS 7's release) to get the UDID without using iTunes on a PC/Mac?

I think iTunes looks to be the only answer, which is extremely unfortunate.

Creating a new DOM element from an HTML string using built-in DOM methods or Prototype

You can use the following function to convert the text "HTML" to the element

_x000D_
_x000D_
function htmlToElement(html)_x000D_
{_x000D_
  var element = document.createElement('div');_x000D_
  element.innerHTML = html;_x000D_
  return(element);_x000D_
}_x000D_
var html="<li>text and html</li>";_x000D_
var e=htmlToElement(html);
_x000D_
_x000D_
_x000D_

How do I enable FFMPEG logging and where can I find the FFMPEG log file?

ffmpeg logs to stderr, and can log to a file with a different log-level from stderr. The -report command-line option doesn't give you control of the log file name or the log level, so setting the environment variable is preferable.

(-v is a synonym for -loglevel. Run ffmpeg -v help to see the levels. Run ffmpeg -h full | less to see EVERYTHING. Or consult the online docs, or their wiki pages like the h.264 encode guide).

#!/bin/bash

of=out.mkv
FFREPORT="level=32:file=$of.log" ffmpeg -v verbose   -i src.mp4 -c:a copy -preset slower -c:v libx264 -crf 21 "$of"

That will trancode src.mp4 with x264, and set the log level for stderr to "verbose", and the log level for out.mkv.log to "status".

(AV_LOG_WARNING=24, AV_LOG_INFO=32, AV_LOG_VERBOSE=40, etc.). Support for this was added 2 years ago, so you need a non-ancient version of ffmpeg. (Always a good idea anyway, for security / bugfixes and speedups)


A few codecs, like -c:v libx265, write directly to stderr instead of using ffmpeg's logging infrastructure. So their log messages don't end up in the report file. I assume this is a bug / TODO-list item.

To log stderr, while still seeing it in a terminal, you can use tee(1).


If you use a log level that includes status line updates (the default -v info, or higher), they will be included in the log file, separated with ^M (carriage return aka \r). There's no log level that includes encoder stats (like SSIM) but not status-line updates, so the best option is probably to filter that stream.

If don't want to filter (e.g. so the fps / bitrate at each status-update interval is there in the file), you can use less -r to pass them through directly to your terminal so you can view the files cleanly. If you have .enc logs from several encodes that you want to flip through, less -r ++G *.enc works great. (++G means start at the end of the file, for all files). With single-key key bindings like . and , for next file and previous file, you can flip through some log files very nicely. (the default bindings are :n and :p).

If you do want to filter, sed 's/.*\r//' works perfectly for ffmpeg output. (In the general case, you need something like vt100.py, but not for just carriage returns). There are (at least) two ways to do this with tee + sed: tee to /dev/tty and pipe tee's output into sed, or use a process substitution to tee into a pipe to sed.

# pass stdout and stderr through to the terminal, 
## and log a filtered version to a file (with only the last status-line update).

of="$1-x265.mkv"
ffmpeg -v info -i "$1" -c:a copy -c:v libx265 ... "$of" |&    # pipe stdout and stderr
   tee /dev/tty | sed 's/.*\r//' >> "$of.enc"

## or with process substitution where tee's arg will be something like /dev/fd/123

ffmpeg -v info -i "$1" -c:a copy -c:v libx265 ... "$of" |&
  tee >(sed 's/.*\r//' >> "$of.enc")

For testing a few different encode parameters, you can make a function like this one that I used recently to test some stuff. I had it all on one line so I could easily up-arrow and edit it, but I'll un-obfuscate it here. (That's why there are ;s at the end of each line)

ffenc-testclip(){
  # v should be set by the caller, to a vertical resolution.  We scale to WxH, where W is a multiple of 8 (-vf scale=-8:$v)
  db=0;   # convenient to use shell vars to encode settings that you want to include in the filename and the ffmpeg cmdline
  [email protected].${v}p.x265$pre.mkv; 
  [[ -e "$of.enc" ]]&&echo "$of.enc exists"&&return;   # early-out if the file exists

  # encode 25 seconds starting at 21m15s (or the keyframe before that)
  nice -14 ffmpeg -ss $((21*60+15))  -i src.mp4 -t 25  -map 0 -metadata title= -color_primaries bt709 -color_trc bt709 -colorspace bt709 -sws_flags lanczos+print_info -c:a copy -c:v libx265 -b:v 1500k -vf scale=-8:$v  -preset $pre -ssim 1 -x265-params ssim=1:cu-stats=1:deblock=$db:aq-mode=1:lookahead-slices=0 "$of" |&
   tee /dev/tty | sed 's/.*\r//' >> "$of.enc";
}

# and use it with nested loops like this.
for pre in fast slow;  do for v in  360 480 648 792;do  ffenc-testclip ;done;done

less -r ++G *.enc       # -r is useful if you didn't use sed

Note that it tests for existence of the output video file to avoid spewing extra garbage into the log file if it already exists. Even so, I used and append (>>) redirect.

It would be "cleaner" to write a shell function that took args instead of looking at shell variables, but this was convenient and easy to write for my own use. That's also why I saved space by not properly quoting all my variable expansions. ($v instead of "$v")

Can my enums have friendly names?

If you have the following enum:

public enum MyEnum {
    First,
    Second,
    Third
}

You can declare Extension Methods for MyEnum (like you can for any other type). I just whipped this up:

namespace Extension {
    public static class ExtensionMethods {
        public static string EnumValue(this MyEnum e) {
            switch (e) {
                case MyEnum.First:
                    return "First Friendly Value";
                case MyEnum.Second:
                    return "Second Friendly Value";
                case MyEnum.Third:
                    return "Third Friendly Value";
            }
            return "Horrible Failure!!";
        }
    }
}

With this Extension Method, the following is now legal:

Console.WriteLine(MyEnum.First.EnumValue());

Hope this helps!!

Simplest Way to Test ODBC on WIndows

It's been a while but since I precisely have the answer to the question, I'll share it and maybe someone will benefit from it.

Jaime de Los Hoyos wrote a very nice program to precisely do that: ODBC Query Tool.
Unfortunately, Jaime's website is defunct but you can still find the program and its source code at this location:
https://sourceforge.net/projects/odbc-query-tool/files/latest_release/

The program is GUI based and consists of a single executable file, no need to install anything on the machine.

Jaime's profile : https://stackoverflow.com/users/878998/jaime-de-los-hoyos-m
Jaime's posts on a forum talking about his program : https://forum.powerbasic.com/forum/user-to-user-discussions/source-code/48266-odbc-query-tool-retrieve-information-from-any-database-easily

What does -> mean in Python function definitions?

This means the type of result the function returns, but it can be None.

It is widespread in modern libraries oriented on Python 3.x.

For example, it there is in code of library pandas-profiling in many places for example:

def get_description(self) -> dict:

def get_rejected_variables(self, threshold: float = 0.9) -> list:

def to_file(self, output_file: Path or str, silent: bool = True) -> None:
"""Write the report to a file.

How to bind 'touchstart' and 'click' events but not respond to both?

Being for me the best answer the one given by Mottie, I'm just trying to do his code more reusable, so this is my contribution:

bindBtn ("#loginbutton",loginAction);

function bindBtn(element,action){

var flag = false;
$(element).bind('touchstart click', function(e) {
    e.preventDefault();
    if (!flag) {
        flag = true;
        setTimeout(function() {
            flag = false;
        }, 100);
        // do something
        action();
    }
    return false;
});

convert string into array of integers

A quick one for modern browsers:

'14 2'.split(' ').map(Number);

// [14, 2]`

Get size of folder or file

private static long getFolderSize(Path folder) {
        try {
            return Files.walk(folder)
                      .filter(p -> p.toFile().isFile())
                      .mapToLong(p -> p.toFile().length())
                      .sum();
        } catch (IOException e) {
            e.printStackTrace();
            return 0L;
        }

Import CSV file as a pandas DataFrame

import pandas as pd
dataset = pd.read_csv('/home/nspython/Downloads/movie_metadata1.csv')

How to read a text file in project's root directory?

In this code you access to root directory project:

 string _filePath = Path.GetDirectoryName(System.AppDomain.CurrentDomain.BaseDirectory);

then:

StreamReader r = new StreamReader(_filePath + "/cities2.json"))

Message: Trying to access array offset on value of type null

This happens because $cOTLdata is not null but the index 'char_data' does not exist. Previous versions of PHP may have been less strict on such mistakes and silently swallowed the error / notice while 7.4 does not do this anymore.

To check whether the index exists or not you can use isset():

isset($cOTLdata['char_data'])

Which means the line should look something like this:

$len = isset($cOTLdata['char_data']) ? count($cOTLdata['char_data']) : 0;

Note I switched the then and else cases of the ternary operator since === null is essentially what isset already does (but in the positive case).

See whether an item appears more than once in a database column

It should be:

SELECT SalesID, COUNT(*)
FROM AXDelNotesNoTracking
GROUP BY SalesID
HAVING COUNT(*) > 1

Regarding your initial query:

  1. You cannot do a SELECT * since this operation requires a GROUP BY and columns need to either be in the GROUP BY or in an aggregate function (i.e. COUNT, SUM, MIN, MAX, AVG, etc.)
  2. As this is a GROUP BY operation, a HAVING clause will filter it instead of a WHERE

Edit:

And I just thought of this, if you want to see WHICH items are in there more than once (but this depends on which database you are using):

;WITH cte AS (
    SELECT  *, ROW_NUMBER() OVER (PARTITION BY SalesID ORDER BY SalesID) AS [Num]
    FROM    AXDelNotesNoTracking
)
SELECT  *
FROM    cte
WHERE   cte.Num > 1

Of course, this just shows the rows that have appeared with the same SalesID but does not show the initial SalesID value that has appeared more than once. Meaning, if a SalesID shows up 3 times, this query will show instances 2 and 3 but not the first instance. Still, it might help depending on why you are looking for multiple SalesID values.

Edit2:

The following query was posted by APC below and is better than the CTE I mention above in that it shows all rows in which a SalesID has appeared more than once. I am including it here for completeness. I merely added an ORDER BY to keep the SalesID values grouped together. The ORDER BY might also help in the CTE above.

SELECT *
FROM AXDelNotesNoTracking
WHERE SalesID IN
    (     SELECT SalesID
          FROM AXDelNotesNoTracking
          GROUP BY SalesID
          HAVING COUNT(*) > 1
    )
ORDER BY SalesID

Get json value from response

If response is in json and not a string then

alert(response.id);
or
alert(response['id']);

otherwise

var response = JSON.parse('{"id":"2231f87c-a62c-4c2c-8f5d-b76d11942301"}');
response.id ; //# => 2231f87c-a62c-4c2c-8f5d-b76d11942301

bs4.FeatureNotFound: Couldn't find a tree builder with the features you requested: lxml. Do you need to install a parser library?

The error is coming because of the parser you are using. In general, if you have HTML file/code then you need to use html5lib(documentation can be found here) & in-case you have XML file/data then you need to use lxml(documentation can be found here). You can use lxml for HTML file/code also but sometimes it gives an error as above. So, better to choose the package wisely based on the type of data/file. You can also use html_parser which is built-in module. But, this also sometimes do not work.

For more details regarding when to use which package you can see the details here

How to get current html page title with javascript

try like this

$('title').text();

How to use subList()

You could use streams in Java 8. To always get 10 entries at the most, you could do:

dataList.stream().skip(5).limit(10).collect(Collectors.toList());
dataList.stream().skip(30).limit(10).collect(Collectors.toList());

How to bind DataTable to Datagrid

I'd do it this way:

grid1.DataContext = dt.AsEnumerable().Where(x => x < 10).AsEnumerable().CopyToDataTable().AsDataView();

and do whatever query i want between the two AsEnumerable(). If you don't need space for query, you can just do directly this:

grid1.DataContext = dt.AsDataView();

Syntax for a single-line Bash infinite while loop

Using while:

while true; do echo 'while'; sleep 2s; done

Using for Loop:

for ((;;)); do echo 'forloop'; sleep 2; done

Using Recursion, (a little bit different than above, keyboard interrupt won't stop it)

list(){ echo 'recursion'; sleep 2; list; } && list;

Run an Ansible task only when the variable contains a specific string

This works for me in Ansible 2.9:

variable1 = www.example.com. 
variable2 = www.example.org. 

when: ".com" in variable1

and for not:

when: not ".com" in variable2

How do I get the last inserted ID of a MySQL table in PHP?

With PDO:

$pdo->lastInsertId();

With Mysqli:

$mysqli->insert_id;

Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MySQLi - this article will help you decide which. If you choose PDO, here is a good tutorial.

C# IPAddress from string

You've probably miss-typed something above that bit of code or created your own class called IPAddress. If you're using the .net one, that function should be available.

Have you tried using System.Net.IPAddress just in case?

System.Net.IPAddress ipaddress = System.Net.IPAddress.Parse("127.0.0.1");  //127.0.0.1 as an example

The docs on Microsoft's site have a complete example which works fine on my machine.

Get event listeners attached to node using addEventListener

Chrome DevTools, Safari Inspector and Firebug support getEventListeners(node).

getEventListeners(document)

ESLint Parsing error: Unexpected token

"parser": "babel-eslint" helped me to fix the issue

{
    "parser": "babel-eslint",
    "parserOptions": {
        "ecmaVersion": 6,
        "sourceType": "module",
        "ecmaFeatures": {
            "jsx": true,
            "modules": true,
            "experimentalObjectRestSpread": true
        }
    },
    "plugins": [
        "react"
    ],
    "extends": ["eslint:recommended", "plugin:react/recommended"],
    "rules": {
        "comma-dangle": 0,
        "react/jsx-uses-vars": 1,
        "react/display-name": 1,
        "no-unused-vars": "warn",
        "no-console": 1,
        "no-unexpected-multiline": "warn"
    },
    "settings": {
        "react": {
            "pragma": "React",
            "version": "15.6.1"
        }
    }
}

Reference

What is the difference between a generative and a discriminative algorithm?

Imagine your task is to classify a speech to a language.

You can do it by either:

  1. learning each language, and then classifying it using the knowledge you just gained

or

  1. determining the difference in the linguistic models without learning the languages, and then classifying the speech.

The first one is the generative approach and the second one is the discriminative approach.

Check this reference for more details: http://www.cedar.buffalo.edu/~srihari/CSE574/Discriminative-Generative.pdf.

How to change users in TortoiseSVN

When you use Integrated Windows Authentication (i.e., Active Directory Single Sign-On), you authenticate to AD resources automatically with your AD credentials. You've are already signed in to AD and these credentials are reused automatically. Therefore if your server is IWA-enabled (e.g., VisualSVN Server), the server does not ask you to enter username and password, passing --username and --password does not work, and the SVN client does not cache your credentials on disk, too.

When you want to change the user account that's used to contact the server, you need use the Windows Credential Manager on client side. This is also helpful when your computer is not domain joined and you need to store your AD credentials to access your domain resources.

Follow these steps to save the user's domain credentials to Windows Credential Manager on the user's computer:

  1. Start Control Panel | Credential Manager on the client computer.
  2. Click Add a Windows Credential.
  3. As Internet or network address enter the FQDN of the server machine (e.g., svn.example.com).
  4. As Username enter your domain account's username in the DOMAIN\Username format.
  5. Complete the password field and click OK.

Now when you will contact https://svn.example.com/svn/MyRepo or a similar URL, the client or web browser will use the credentials saved in the Credential Manager to authenticate to the server.

enter image description here

Attaching click event to a JQuery object not yet added to the DOM

Complement of information for those people who use .on() to listen to events bound on inputs inside lately loaded table cells; I managed to bind event handlers to such table cells by using delegate(), but .on() wouldn't work.

I bound the table id to .delegate() and used a selector that describes the inputs.

e.g.

HTML

<table id="#mytable">
  <!-- These three lines below were loaded post-DOM creation time, using a live callback for example -->
  <tr><td><input name="qty_001" /></td></tr>
  <tr><td><input name="qty_002" /></td></tr>
  <tr><td><input name="qty_003" /></td></tr>
</table>

jQuery

$('#mytable').delegate('click', 'name^=["qty_"]', function() {
    console.log("you clicked cell #" . $(this).attr("name"));
});

Inserting multiple rows in mysql

If you have your data in a text-file, you can use LOAD DATA INFILE.

When loading a table from a text file, use LOAD DATA INFILE. This is usually 20 times faster than using INSERT statements.

Optimizing INSERT Statements

You can find more tips on how to speed up your insert statements on the link above.

Execute SQL script from command line

You can do like this

sqlcmd -S <server Name> -U sa -P sapassword -i inputquery_file_name -o outputfile_name

From your command prompt run sqlcmd /? to get all the options you can use with sqlcmd utility

How to Select Columns in Editors (Atom,Notepad++, Kate, VIM, Sublime, Textpad,etc) and IDEs (NetBeans, IntelliJ IDEA, Eclipse, Visual Studio, etc)

In Sublime3 (Windows):

Some users may get an inverted screen using the Ctrl+Alt+? in windows. To Solve this go to

Preferences->Key Bindings-User

And add these two lines at the end of the file just before closing brackets:

{ "keys": ["ctrl+alt+pageup"], "command": "select_lines", "args": {"forward": false} },

{ "keys": ["ctrl+alt+pagedown"], "command": "select_lines", "args": {"forward": true} } 

Or use your own keys.

Serialize JavaScript object into JSON string

This might be useful. http://nanodeath.github.com/HydrateJS/ https://github.com/nanodeath/HydrateJS

Use hydrate.stringify to serialize the object and hydrate.parse to deserialize.

Renaming the current file in Vim

Vim does have a rename function, but unfortunately it does not retain the history.

The easiest OS agnostic way to rename a file without losing the history would be:

:saveas new_file_name
:call delete(expand('#:p'))

expand('#:p') returns the full path of the older file.

Use :bd # if you also want to delete the older file from the buffer list.

Or create a plugin

If you want to use a quick command to rename the file, add a new file under ~/.vim/plugin with the following contents:

function! s:rename_file(new_file_path)
  execute 'saveas ' . a:new_file_path
  call delete(expand('#:p'))
  bd #
endfunction

command! -nargs=1 -complete=file Rename call <SID>rename_file(<f-args>)

The command Rename will help you to quickly rename a file.

In Java how does one turn a String into a char or a char into a String?

String someString = "" + c;
char c = someString.charAt(0);

Adding files to java classpath at runtime

You can only add folders or jar files to a class loader. So if you have a single class file, you need to put it into the appropriate folder structure first.

Here is a rather ugly hack that adds to the SystemClassLoader at runtime:

import java.io.IOException;
import java.io.File;
import java.net.URLClassLoader;
import java.net.URL;
import java.lang.reflect.Method;

public class ClassPathHacker {

  private static final Class[] parameters = new Class[]{URL.class};

  public static void addFile(String s) throws IOException {
    File f = new File(s);
    addFile(f);
  }//end method

  public static void addFile(File f) throws IOException {
    addURL(f.toURL());
  }//end method


  public static void addURL(URL u) throws IOException {

    URLClassLoader sysloader = (URLClassLoader) ClassLoader.getSystemClassLoader();
    Class sysclass = URLClassLoader.class;

    try {
      Method method = sysclass.getDeclaredMethod("addURL", parameters);
      method.setAccessible(true);
      method.invoke(sysloader, new Object[]{u});
    } catch (Throwable t) {
      t.printStackTrace();
      throw new IOException("Error, could not add URL to system classloader");
    }//end try catch

   }//end method

}//end class

The reflection is necessary to access the protected method addURL. This could fail if there is a SecurityManager.

Python: Assign print output to a variable

probably you need one of str,repr or unicode functions

somevar = str(tag.getArtist())

depending which python shell are you using

Array or List in Java. Which is faster?

Remember that an ArrayList encapsulates an array, so there is little difference compared to using a primitive array (except for the fact that a List is much easier to work with in java).

The pretty much the only time it makes sense to prefer an array to an ArrayList is when you are storing primitives, i.e. byte, int, etc and you need the particular space-efficiency you get by using primitive arrays.

What is the difference between "long", "long long", "long int", and "long long int" in C++?

long is equivalent to long int, just as short is equivalent to short int. A long int is a signed integral type that is at least 32 bits, while a long long or long long int is a signed integral type is at least 64 bits.

This doesn't necessarily mean that a long long is wider than a long. Many platforms / ABIs use the LP64 model - where long (and pointers) are 64 bits wide. Win64 uses the LLP64, where long is still 32 bits, and long long (and pointers) are 64 bits wide.

There's a good summary of 64-bit data models here.

long double doesn't guarantee much other than it will be at least as wide as a double.

HTTPS using Jersey Client

Construct your client as such

HostnameVerifier hostnameVerifier = HttpsURLConnection.getDefaultHostnameVerifier();
ClientConfig config = new DefaultClientConfig();
SSLContext ctx = SSLContext.getInstance("SSL");
ctx.init(null, myTrustManager, null);
config.getProperties().put(HTTPSProperties.PROPERTY_HTTPS_PROPERTIES, new HTTPSProperties(hostnameVerifier, ctx));
Client client = Client.create(config);

Ripped from this blog post with more details: http://blogs.oracle.com/enterprisetechtips/entry/consuming_restful_web_services_with

For information on setting up your certs, see this nicely answered SO question: Using HTTPS with REST in Java

javascript regex for special characters

a sleaker way to match special chars:

/\W|_/g

\W Matches any character that is not a word character (alphanumeric & underscore).

Underscore is considered a special character so add boolean to either match a special character or _

What does '?' do in C++?

Just a note, if you ever see this:

a = x ? : y;

It's a GNU extension to the standard (see https://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals).

It is the same as

a = x ? x : y;

C# version of java's synchronized keyword?

Does c# have its own version of the java "synchronized" keyword?

No. In C#, you explicitly lock resources that you want to work on synchronously across asynchronous threads. lock opens a block; it doesn't work on method level.

However, the underlying mechanism is similar since lock works by invoking Monitor.Enter (and subsequently Monitor.Exit) on the runtime. Java works the same way, according to the Sun documentation.

How to access a DOM element in React? What is the equilvalent of document.getElementById() in React

For getting the element in react you need to use ref and inside the function you can use the ReactDOM.findDOMNode method.

But what I like to do more is to call the ref right inside the event

<input type="text" ref={ref => this.myTextInput = ref} />

This is some good link to help you figure out.

Pointtype command for gnuplot

You first have to tell Gnuplot to use a style that uses points, e.g. with points or with linespoints. Try for example:

plot sin(x) with points

Output:

Now try:

plot sin(x) with points pointtype 5

Output:

You may also want to look at the output from the test command which shows you the capabilities of the current terminal. Here are the capabilities for my pngairo terminal:

NSDate get year/month/day

Try the following:

    NSString *birthday = @"06/15/1977";
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"MM/dd/yyyy"];
    NSDate *date = [formatter dateFromString:birthday];
    if(date!=nil) {
        NSInteger age = [date timeIntervalSinceNow]/31556926;
        NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:date];
        NSInteger day = [components day];
        NSInteger month = [components month];
        NSInteger year = [components year];

        NSLog(@"Day:%d Month:%d Year:%d Age:%d",day,month,year,age);
    }
    [formatter release];

Secure FTP using Windows batch script

First, make sure you understand, if you need to use Secure FTP (=FTPS, as per your text) or SFTP (as per tag you have used).

Neither is supported by Windows command-line ftp.exe. As you have suggested, you can use WinSCP. It supports both FTPS and SFTP.

Using WinSCP, your batch file would look like (for SFTP):

echo open sftp://ftp_user:[email protected] -hostkey="server's hostkey" >> ftpcmd.dat
echo put c:\directory\%1-export-%date%.csv >> ftpcmd.dat
echo exit >> ftpcmd.dat
winscp.com /script=ftpcmd.dat
del ftpcmd.dat

And the batch file:

winscp.com /log=ftpcmd.log /script=ftpcmd.dat /parameter %1 %date%

Though using all capabilities of WinSCP (particularly providing commands directly on command-line and the %TIMESTAMP% syntax), the batch file simplifies to:

winscp.com /log=ftpcmd.log /command ^
    "open sftp://ftp_user:[email protected] -hostkey=""server's hostkey""" ^
    "put c:\directory\%1-export-%%TIMESTAMP#yyyymmdd%%.csv" ^
    "exit"

For the purpose of -hostkey switch, see verifying the host key in script.

Easier than assembling the script/batch file manually is to setup and test the connection settings in WinSCP GUI and then have it generate the script or batch file for you:

Generate batch file

All you need to tweak is the source file name (use the %TIMESTAMP% syntax as shown previously) and the path to the log file.


For FTPS, replace the sftp:// in the open command with ftpes:// (explicit TLS/SSL) or ftps:// (implicit TLS/SSL). Remove the -hostkey switch.

winscp.com /log=ftpcmd.log /command ^
    "open ftps://ftp_user:[email protected] -explicit" ^
    "put c:\directory\%1-export-%%TIMESTAMP#yyyymmdd%%.csv" ^
    "exit"

You may need to add the -certificate switch, if your server's certificate is not issued by a trusted authority.

Again, as with the SFTP, easier is to setup and test the connection settings in WinSCP GUI and then have it generate the script or batch file for you.


See a complete conversion guide from ftp.exe to WinSCP.

You should also read the Guide to automating file transfers to FTP server or SFTP server.


Note to using %TIMESTAMP#yyyymmdd% instead of %date%: A format of %date% variable value is locale-specific. So make sure you test the script on the same locale you are actually going to use the script on. For example on my Czech locale the %date% resolves to ct 06. 11. 2014, what might be problematic when used as a part of a file name.

For this reason WinSCP supports (locale-neutral) timestamp formatting natively. For example %TIMESTAMP#yyyymmdd% resolves to 20170515 on any locale.

(I'm the author of WinSCP)

How do I update a formula with Homebrew?

You can update all outdated packages like so:

brew install `brew outdated`

or

brew outdated | xargs brew install

or

brew upgrade

This is from the brew site..

for upgrading individual formula:

brew install formula-name && brew cleanup formula-name

What does %>% mean in R

matrix multiplication, see the following example:

> A <- matrix (c(1,3,4, 5,8,9, 1,3,3), 3,3)
> A
     [,1] [,2] [,3]
[1,]    1    5    1
[2,]    3    8    3
[3,]    4    9    3
> 
> B <- matrix (c(2,4,5, 8,9,2, 3,4,5), 3,3)
> 
> B
     [,1] [,2] [,3]
[1,]    2    8    3
[2,]    4    9    4
[3,]    5    2    5
> 
> 
> A %*% B
     [,1] [,2] [,3]
[1,]   27   55   28
[2,]   53  102   56
[3,]   59  119   63

> B %*% A
     [,1] [,2] [,3]
[1,]   38  101   35
[2,]   47  128   43
[3,]   31   86   26

Also see:

http://en.wikipedia.org/wiki/Matrix_multiplication

If this does not follow the size of matrix rule you will get the error:

> A <- matrix(c(1,2,3,4,5,6), 3,2)
    > A
     [,1] [,2]
[1,]    1    4
[2,]    2    5
[3,]    3    6

> B <- matrix (c(3,1,3,4,4,4,4,4,3), 3,3)

> B
         [,1] [,2] [,3]
    [1,]    3    4    4
    [2,]    1    4    4
    [3,]    3    4    3
    > A%*%B
    Error in A %*% B : non-conformable arguments

How to get pixel data from a UIImage (Cocoa Touch) or CGImage (Core Graphics)?

Apple's Technical Q&A QA1509 shows the following simple approach:

CFDataRef CopyImagePixels(CGImageRef inImage)
{
    return CGDataProviderCopyData(CGImageGetDataProvider(inImage));
}

Use CFDataGetBytePtr to get to the actual bytes (and various CGImageGet* methods to understand how to interpret them).

Capturing browser logs with Selenium WebDriver using Java

Driver manager logs can be used to get console logs from browser and it will help to identify errors appears in console.

   import org.openqa.selenium.logging.LogEntries;
   import org.openqa.selenium.logging.LogEntry;

    public List<LogEntry> getBrowserConsoleLogs()
    {
    LogEntries log= driver.manage().logs().get("browser")
    List<LogEntry> logs=log.getAll();
    return logs;
    }

Can we convert a byte array into an InputStream in Java?

If you use Robert Harder's Base64 utility, then you can do:

InputStream is = new Base64.InputStream(cph);

Or with sun's JRE, you can do:

InputStream is = new
com.sun.xml.internal.messaging.saaj.packaging.mime.util.BASE64DecoderStream(cph)

However don't rely on that class continuing to be a part of the JRE, or even continuing to do what it seems to do today. Sun say not to use it.

There are other Stack Overflow questions about Base64 decoding, such as this one.

Putting GridView data in a DataTable

user this full solution to convert gridview to datatable

 public DataTable gridviewToDataTable(GridView gv)
        {

            DataTable dtCalculate = new DataTable("TableCalculator");

            // Create Column 1: Date
            DataColumn dateColumn = new DataColumn();
            dateColumn.DataType = Type.GetType("System.DateTime");
            dateColumn.ColumnName = "date";

            // Create Column 3: TotalSales
            DataColumn loanBalanceColumn = new DataColumn();
            loanBalanceColumn.DataType = Type.GetType("System.Double");
            loanBalanceColumn.ColumnName = "loanbalance";


            DataColumn offsetBalanceColumn = new DataColumn();
            offsetBalanceColumn.DataType = Type.GetType("System.Double");
            offsetBalanceColumn.ColumnName = "offsetbalance";


            DataColumn netloanColumn = new DataColumn();
            netloanColumn.DataType = Type.GetType("System.Double");
            netloanColumn.ColumnName = "netloan";


            DataColumn interestratecolumn = new DataColumn();
            interestratecolumn.DataType = Type.GetType("System.Double");
            interestratecolumn.ColumnName = "interestrate";

            DataColumn interestrateperdaycolumn = new DataColumn();
            interestrateperdaycolumn.DataType = Type.GetType("System.Double");
            interestrateperdaycolumn.ColumnName = "interestrateperday";

            // Add the columns to the ProductSalesData DataTable
            dtCalculate.Columns.Add(dateColumn);
            dtCalculate.Columns.Add(loanBalanceColumn);
            dtCalculate.Columns.Add(offsetBalanceColumn);
            dtCalculate.Columns.Add(netloanColumn);
            dtCalculate.Columns.Add(interestratecolumn);
            dtCalculate.Columns.Add(interestrateperdaycolumn);

            foreach (GridViewRow row in gv.Rows)
            {
                DataRow dr;
                dr = dtCalculate.NewRow();

                dr["date"] = DateTime.Parse(row.Cells[0].Text);
                dr["loanbalance"] = double.Parse(row.Cells[1].Text);
                dr["offsetbalance"] = double.Parse(row.Cells[2].Text);
                dr["netloan"] = double.Parse(row.Cells[3].Text);
                dr["interestrate"] = double.Parse(row.Cells[4].Text);
                dr["interestrateperday"] = double.Parse(row.Cells[5].Text);


                dtCalculate.Rows.Add(dr);
            }



            return dtCalculate;
        }

What's the difference between a Future and a Promise?

I am aware that there's already an accepted answer but would like to add my two cents nevertheless:

TLDR: Future and Promise are the two sides of an asynchronous operation: consumer/caller vs. producer/implementor.

As a caller of an asynchronous API method, you will get a Future as a handle to the computation's result. You can e.g. call get() on it to wait for the computation to complete and retrieve the result.

Now think of how this API method is actually implemented: The implementor must return a Future immediately. They are responsible for completing that future as soon as the computation is done (which they will know because it is implementing the dispatch logic ;-)). They will use a Promise/CompletableFuture to do just that: Construct and return the CompletableFuture immediately, and call complete(T result) once the computation is done.

I am getting "java.lang.ClassNotFoundException: com.google.gson.Gson" error even though it is defined in my classpath

Click on Deployment Assembly ( right above Java Build Path that you show as active ) and make sure that you see json-lib-2.4-jdk15.jar there.

Usually, you should add it to your build path and export it from your project. Once it's exported you will see the WTP warning that it's not a part of the deployment. Choose the Quick Fix option and add it to your deployment path.

Delete column from pandas DataFrame

The best way to do this in pandas is to use drop:

df = df.drop('column_name', 1)

where 1 is the axis number (0 for rows and 1 for columns.)

To delete the column without having to reassign df you can do:

df.drop('column_name', axis=1, inplace=True)

Finally, to drop by column number instead of by column label, try this to delete, e.g. the 1st, 2nd and 4th columns:

df = df.drop(df.columns[[0, 1, 3]], axis=1)  # df.columns is zero-based pd.Index 

Also working with "text" syntax for the columns:

df.drop(['column_nameA', 'column_nameB'], axis=1, inplace=True)

Note: Introduced in v0.21.0 (October 27, 2017), the drop() method accepts index/columns keywords as an alternative to specifying the axis.

So we can now just do:

df.drop(columns=['B', 'C'])

appending list but error 'NoneType' object has no attribute 'append'

When doing pan_list.append(p.last) you're doing an inplace operation, that is an operation that modifies the object and returns nothing (i.e. None).

You should do something like this :

last_list=[]
if p.last_name==None or p.last_name=="": 
    pass
last_list.append(p.last)  # Here I modify the last_list, no affectation
print last_list

How to reload the current route with the angular 2 router

This works for me like a charm

this.router.navigateByUrl('/', {skipLocationChange: true}).then(()=>
this.router.navigate([<route>]));

How to output git log with the first line only?

git log --format="%H" -n 1

Use the above command to get the commitid, hope this helps.

parsing JSONP $http.jsonp() response in angular.js

The MOST IMPORTANT THING I didn't understand for quite awhile is that the request MUST contain "callback=JSON_CALLBACK", because AngularJS modifies the request url, substituting a unique identifier for "JSON_CALLBACK". The server response must use the value of the 'callback' parameter instead of hard coding "JSON_CALLBACK":

JSON_CALLBACK(json_response);  // wrong!

Since I was writing my own PHP server script, I thought I knew what function name it wanted and didn't need to pass "callback=JSON_CALLBACK" in the request. Big mistake!

AngularJS replaces "JSON_CALLBACK" in the request with a unique function name (like "callback=angular.callbacks._0"), and the server response must return that value:

angular.callbacks._0(json_response);

How to use GNU Make on Windows?

As an alternative, if you just want to install make, you can use the chocolatey package manager to install gnu make by using

choco install make -y

This deals with any path issues that you might have.

Curl : connection refused

Try curl -v http://localhost:8080/ instead of 127.0.0.1

How to execute a .sql script from bash

If you want to run a script to a database:

mysql -u user -p data_base_name_here < db.sql

How to redirect 'print' output to a file using python?

If redirecting stdout works for your problem, Gringo Suave's answer is a good demonstration for how to do it.

To make it even easier, I made a version utilizing contextmanagers for a succinct generalized calling syntax using the with statement:

from contextlib import contextmanager
import sys

@contextmanager
def redirected_stdout(outstream):
    orig_stdout = sys.stdout
    try:
        sys.stdout = outstream
        yield
    finally:
        sys.stdout = orig_stdout

To use it, you just do the following (derived from Suave's example):

with open('out.txt', 'w') as outfile:
    with redirected_stdout(outfile):
        for i in range(2):
            print('i =', i)

It's useful for selectively redirecting print when a module uses it in a way you don't like. The only disadvantage (and this is the dealbreaker for many situations) is that it doesn't work if one wants multiple threads with different values of stdout, but that requires a better, more generalized method: indirect module access. You can see implementations of that in other answers to this question.

Simple way to read single record from MySQL

Better if SQL will be optimized with addion of LIMIT 1 in the end:

$query = "select id from games LIMIT 1";


SO ANSWER IS (works on php 5.6.3):

If you want to get first item of first row(even if it is not ID column):

queryExec($query) -> fetch_array()[0];

If you want to get first row(single item from DB)

queryExec($query) -> fetch_assoc();

If you want to some exact column from first row

queryExec($query) -> fetch_assoc()['columnName'];

or need to fix query and use first written way :)

What are the differences between LDAP and Active Directory?

Active Directory isn't just an implementation of LDAP by Microsoft, that is only a small part of what AD is. Active Directory is (in an overly simplified way) a service that provides LDAP based authentication with Kerberos based Authorization.

Of course their LDAP and Kerberos implementations in AD are not exactly 100% interoperable with other LDAP/Kerberos implementations...

Creating email templates with Django

Boys and Girls!

Since Django's 1.7 in send_email method the html_message parameter was added.

html_message: If html_message is provided, the resulting email will be a multipart/alternative email with message as the text/plain content type and html_message as the text/html content type.

So you can just:

from django.core.mail import send_mail
from django.template.loader import render_to_string


msg_plain = render_to_string('templates/email.txt', {'some_params': some_params})
msg_html = render_to_string('templates/email.html', {'some_params': some_params})

send_mail(
    'email title',
    msg_plain,
    '[email protected]',
    ['[email protected]'],
    html_message=msg_html,
)

Display a float with two decimal places in Python

Using Python 3 syntax:

print('%.2f' % number)

Putting a simple if-then-else statement on one line

General ternary syntax:

value_true if <test> else value_false

Another way can be:

[value_false, value_true][<test>]

e.g:

count = [0,N+1][count==N]

This evaluates both branches before choosing one. To only evaluate the chosen branch:

[lambda: value_false, lambda: value_true][<test>]()

e.g.:

count = [lambda:0, lambda:N+1][count==N]()

How to convert array to SimpleXML

I would have commented the second most voted answer, because it doesn't preserve structure and generates bad xml if there is numerically indexed inner arrays.

I developed my own version based on it, because I needed simple converter between json and xml regardless of the structure of data. My version preserves numeric key information and structure of the original array. It creates elements for the numerically indexed values by wrapping values to value -named elements with key-attribute that contains numerical key.

For example

array('test' => array(0 => 'some value', 1 => 'other'))

converts to

<test><value key="0">some value</value><value key="1">other</value></test>

My version of array_to_xml -function (hope it helps somebody :)

function array_to_xml($arr, &$xml) {
    foreach($arr as $key => $value) {
        if(is_array($value)) {
            if(!is_numeric($key)){
                $subnode = $xml->addChild("$key");
            } else {
                $subnode = $xml->addChild("value");
                $subnode->addAttribute('key', $key);                    
            }
            array_to_xml($value, $subnode);
        }
        else {
            if (is_numeric($key)) {
                $xml->addChild("value", $value)->addAttribute('key', $key);
            } else {
                $xml->addChild("$key",$value);
            }
        }
    }
}   

Way to get all alphabetic chars in an array in PHP?

Another way:

$c = 'A';
$chars = array($c);
while ($c < 'Z') $chars[] = ++$c;

How to export specific request to file using postman?

There is no direct option to export a single request from Postman.

You can create and export collections. Here is a link to help with that.

Regarding the single request thing, you can try a workaround. I tried with the RAW body parameters and it worked.

What you can do is,

  1. In your request tab, click on the 3 dots in the top right corner of your request panel/box. enter image description here

  2. Select Code. This will open Generate Code Snippents window. enter image description here

  3. Copy the cURL code and save it in a text file. Share this with who you want to. enter image description here

  4. They can then import the request from the text file. enter image description here

How do I create a SQL table under a different schema?

Shaun F's answer will not work if Schema doesn't exist in the DB. If anyone is looking for way to create schema then just execute following script to create schema.

create schema [schema_name]
CREATE TABLE [schema_name].[table_name](
 ...
) ON [PRIMARY]

While adding new table, go to table design mode and press F4 to open property Window and select the schema from dropdown. Default is dbo.

You can also change the schema of the current Table using Property window.

Refer:

enter image description here

How we can bold only the name in table td tag not the value

Try this

_x000D_
_x000D_
.Bold { font-weight: bold; }
_x000D_
<span> normal text</span> <br>_x000D_
<span class="Bold"> bold text</span> <br>_x000D_
<span> normal text</span> <spanspan>
_x000D_
_x000D_
_x000D_

Should I use window.navigate or document.location in JavaScript?

window.location also affects to the frame,

the best form i found is:

parent.window.location.href

And the worse is:

parent.document.URL 

I did a massive browser test, and some rare IE with several plugins get undefined with the second form.

Set div height equal to screen size

This worked for me JsFiddle

Html

..bootstrap
<div class="row">
  <div class="col-4 window-full" style="background-color:green">
    First Col
  </div>
  <div class="col-8">
    Column-8
  </div>
</div>

css

.row {
   background: #f8f9fa;
   margin-top: 20px;
}

 .col {
   border: solid 1px #6c757d;
   padding: 10px;
}

JavaScript

var elements = document.getElementsByClassName('window-full');
var windowheight = window.innerHeight + "px";

fullheight(elements);
function fullheight(elements) {
    for(let el in elements){
        if(elements.hasOwnProperty(el)){
            elements[el].style.height = windowheight;
        }
    }
}

window.onresize = function(event){
     fullheight(elements);
}

Checkout JsFiddle link JsFiddle

regular expression for DOT

You should use contains not matches

if(nom.contains("."))
    System.out.println("OK");
else
    System.out.println("Bad");

Iterating over each line of ls -l output

It depends what you want to do with each line. awk is a useful utility for this type of processing. Example:

 ls -l | awk '{print $9, $5}'

.. on my system prints the name and size of each item in the directory.

mvn command is not recognized as an internal or external command

I also was facing with the same issue still after adding path in environment variable and running it as a normal user in command prompt.

Then I opened command prompt and tried running as "Run as Administrator" and I was able to download all the packages with respect to the project.

What are some great online database modeling tools?

Do you mean design as in 'graphic representation of tables' or just plain old 'engineering kind of design'. If it's the latter, use FlameRobin, version 0.9.0 has just been released.

If it's the former, then use DBDesigner. Yup, that uses Java.

Or maybe you meant something more like MS Access. Then Kexi should be right for you.

Switching to landscape mode in Android Emulator

To rotate the Android Emulator, just disable the Num Lock key and and use the 7 and the 9 in the num pad to rotate the emulator and change its layout from portrait to landscape.

Prevent a webpage from navigating away using JavaScript

The equivalent to the accepted answer in jQuery 1.11:

$(window).on("beforeunload", function () {
    return "Please don't leave me!";
});

JSFiddle example

altCognito's answer used the unload event, which happens too late for JavaScript to abort the navigation.

How to select the last record from MySQL table using SQL syntax

User order by with desc order:

select * from t
order by id desc
limit 1

Java String to JSON conversion

Converting the String to JsonNode using ObjectMapper object :

ObjectMapper mapper = new ObjectMapper();

// For text string
JsonNode = mapper.readValue(mapper.writeValueAsString("Text-string"), JsonNode.class)

// For Array String
JsonNode = mapper.readValue("[\"Text-Array\"]"), JsonNode.class)

// For Json String 
String json = "{\"id\" : \"1\"}";
ObjectMapper mapper = new ObjectMapper();
JsonFactory factory = mapper.getFactory();
JsonParser jsonParser = factory.createParser(json);
JsonNode node = mapper.readTree(jsonParser);

Trying to handle "back" navigation button action in iOS

Set the UINavigationControllerDelegate and implement this delegate func (Swift):

func navigationController(navigationController: UINavigationController, willShowViewController viewController: UIViewController, animated: Bool) {
    if viewController is <target class> {
        //if the only way to get back - back button was pressed
    }
}

print call stack in C or C++

There is no standardized way to do that. For windows the functionality is provided in the DbgHelp library

How to convert a huge list-of-vector to a matrix more efficiently?

This should be equivalent to your current code, only a lot faster:

output <- matrix(unlist(z), ncol = 10, byrow = TRUE)

Get type of all variables

> mtcars %>% 
+     summarise_all(typeof) %>% 
+     gather
    key  value
1   mpg double
2   cyl double
3  disp double
4    hp double
5  drat double
6    wt double
7  qsec double
8    vs double
9    am double
10 gear double
11 carb double

I try class and typeof functions, but all fails.

Redirecting to a new page after successful login

Javascript redirection generated with php code:

 if($match > 0){
     $msg = 'Login Complete! Thanks';
     echo "<script> window.location.assign('index.php'); </script>";
 }
 else{
     $msg = 'Login Failed!<br /> Please make sure that you enter the correct  details and that you have activated your account.';
 }

Php redirection only:

<?php
    header("Location: index.php"); 
    exit;
?>

Ternary operator ?: vs if...else

They are the same, however, the ternary operator can be used in places where it is difficult to use a if/else:

printf("Total: %d item%s", cnt, cnt != 1 ? "s" : "");

Doing that statement with an if/else, would generate a very different compiled code.


Update after 8 years...

Actually, I think this would be better:

printf(cnt == 1 ? "Total: %d item" : "Total: %d items", cnt);

(actually, I'm pretty sure you can replace the "%d" in the first string with "one")

Does bootstrap 4 have a built in horizontal divider?

Bootstrap 4 define a CSS style for the HTML built-in horizontal divider <hr />, so just use it.

You can also customize margin with spacing utilities: mt for margin top, mb for margin bottom and my for margin top and bottom. The integer represent spacing 1 for small margin and 5 for huge margin. Here is an example:

<hr class="mt-2 mb-3"/>
<!-- OR -->
<hr class="my-3"/>
<!-- It's like -->
<hr class="mt-3 mb-3"/>

I used to be using just a div with border-top like:

<div class="border-top my-3"></div>

but it's a silly method to make the work done, and you can have some issues. So just use <hr />.

IndexOf function in T-SQL

You can use either CHARINDEX or PATINDEX to return the starting position of the specified expression in a character string.

CHARINDEX('bar', 'foobar') == 4
PATINDEX('%bar%', 'foobar') == 4

Mind that you need to use the wildcards in PATINDEX on either side.

How to get a string after a specific substring?

In Python 3.9, a new removeprefix method is being added:

>>> 'TestHook'.removeprefix('Test')
'Hook'
>>> 'BaseTestCase'.removeprefix('Test')
'BaseTestCase'

How to remove folders with a certain name

To delete all directories with the name foo, run:

find -type d -name foo -a -prune -exec rm -rf {} \;

The other answers are missing an important thing: the -prune option. Without -prune, GNU find will delete the directory with the matching name and then try to recurse into it to find more directories that match. The -prune option tells it to not recurse into a directory that matched the conditions.

LaTeX: Prevent line break in a span of text

Also, if you have two subsequent words in regular text and you want to avoid a line break between them, you can use the ~ character.

For example:

As we can see in Fig.~\ref{BlaBla}, there is nothing interesting to see. A~better place..

This can ensure that you don't have a line starting with a figure number (without the Fig. part) or with an uppercase A.

How to cast the size_t to double or int C++

Static cast:

static_cast<int>(data);

How to print a certain line of a file with PowerShell?

This will show the 10th line of myfile.txt:

get-content myfile.txt | select -first 1 -skip 9

both -first and -skip are optional parameters, and -context, or -last may be useful in similar situations.

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

In .NET4.5, MVC 5

Javascript:

object in JS: enter image description here

mechanism that does post.

    $('.button-green-large').click(function() {
        $.ajax({
            url: 'Quote',
            type: "POST",
            dataType: "json",
            data: JSON.stringify(document.selectedProduct),
            contentType: 'application/json; charset=utf-8',
        });
    });

C#

Objects:

public class WillsQuoteViewModel
{
    public string Product { get; set; }

    public List<ClaimedFee> ClaimedFees { get; set; }
}

public partial class ClaimedFee //Generated by EF6
{
    public long Id { get; set; }
    public long JourneyId { get; set; }
    public string Title { get; set; }
    public decimal Net { get; set; }
    public decimal Vat { get; set; }
    public string Type { get; set; }

    public virtual Journey Journey { get; set; }
}

Controller:

[AcceptVerbs(HttpVerbs.Post)]
public ActionResult Quote(WillsQuoteViewModel data)
{
....
}

Object received:

enter image description here

Hope this saves you some time.

Python string prints as [u'String']

Do you really mean u'String'?

In any event, can't you just do str(string) to get a string rather than a unicode-string? (This should be different for Python 3, for which all strings are unicode.)

No resource found that matches the given name: attr 'android:keyboardNavigationCluster'. when updating to Support Library 26.0.0

//Adding this to the root build.gradle solved my problem, thanks @Yalamber
subprojects {
        afterEvaluate { project ->
            if (project.hasProperty("android")) {
                android {
                    compileSdkVersion 26
                    buildToolsVersion '26.0.2'
                }
            }
        }
    }

Java creating .jar file

In order to create a .jar file, you need to use jar instead of java:

jar cf myJar.jar myClass.class

Additionally, if you want to make it executable, you need to indicate an entry point (i.e., a class with public static void main(String[] args)) for your application. This is usually accomplished by creating a manifest file that contains the Main-Class header (e.g., Main-Class: myClass).

However, as Mark Peters pointed out, with JDK 6, you can use the e option to define the entry point:

jar cfe myJar.jar myClass myClass.class 

Finally, you can execute it:

java -jar myJar.jar

See also

What is JNDI? What is its basic use? When is it used?

I will use one example to explain how JNDI can be used to configure database without any application developer knowing username and password of the database.

1) We have configured the data source in JBoss server's standalone-full.xml. Additionally, we can configure pool details also.

 <datasource jta="false" jndi-name="java:/DEV.DS" pool-name="DEV" enabled="true" use-ccm="false">
                <connection-url>jdbc:oracle:thin:@<IP>:1521:DEV</connection-url>
                <driver-class>oracle.jdbc.OracleDriver</driver-class>
                <driver>oracle</driver>
                <security>
                    <user-name>usname</user-name>
                    <password>pass</password>
                    </security>
                    <security>

 <security-domain>encryptedSecurityDomain</security-domain>
                    </security>

                <validation>
                    <validate-on-match>false</validate-on-match>
                    <background-validation>false</background-validation>
                    <background-validation-millis>1</background-validation-millis>
                </validation>
                <statement>
                    <prepared-statement-cache-size>0</prepared-statement-cache-size>
                    <share-prepared-statements>false</share-prepared-statements>
                    <pool>
                        <min-pool-size>5</min-pool-size>
                        <max-pool-size>10</max-pool-size>
                    </pool>
                </statement>
            </datasource>

enter image description here

Now, this jndi-name and its associated datasource object will be available for our application.application.

2) We can retrieve this datasource object using JndiDataSourceLookup class.

enter image description here

Spring will instantiate the datasource bean, after we provide the jndi-name.

Now, we can change the pool size, user name or password as per our environment or requirement, but it will not impact the application.

Note : encryptedSecurityDomain, we need to configure it separately in JBoss server like

<security-domain name="encryptedSecurityDomain" cache-type="default">
                    <authentication>
                        <login-module code="org.picketbox.datasource.security.SecureIdentityLoginModule" flag="required">
                            <module-option name="username" value="<usernamefordb>"/>
                            <module-option name="password" value="894c8a6aegc8d028ce169c596d67afd0"/>
                        </login-module>
                    </authentication>
                </security-domain>

This is one of the use cases. Hope it clarifies.

Javascript split regex question

try this instead

date.split(/\W+/)

Check whether a string matches a regex in JS

Use /youregexp/.test(yourString) if you only want to know whether your string matches the regexp.

Listening for variable changes in JavaScript

As Luke Schafer's answer (note: this refers to his original post; but the whole point here remains valid after the edit), I would also suggest a pair of Get/Set methods to access your value.

However I would suggest some modifications (and that's why I'm posting...).

A problem with that code is that the field a of the object myobj is directly accessible, so it's possible to access it / change its value without triggering the listeners:

var myobj = { a : 5, get_a : function() { return this.a;}, set_a : function(val) { this.a = val; }}
/* add listeners ... */
myobj.a = 10; // no listeners called!

Encapsulation

So, to guarantee that the listeners are actually called, we would have to prohibit that direct access to the field a. How to do so? Use a closure!

var myobj = (function() { // Anonymous function to create scope.

    var a = 5;            // 'a' is local to this function
                          // and cannot be directly accessed from outside
                          // this anonymous function's scope

    return {
        get_a : function() { return a; },   // These functions are closures:
        set_a : function(val) { a = val; }  // they keep reference to
                                            // something ('a') that was on scope
                                            // where they were defined
    };
})();

Now you can use the same method to create and add the listeners as Luke proposed, but you can rest assured that there's no possible way to read from or write to a going unnoticed!

Adding encapsulated fields programmatically

Still on Luke's track, I propose now a simple way to add encapsulated fields and the respective getters/setters to objects by the means of a simple function call.

Note that this will only work properly with value types. For this to work with reference types, some kind of deep copy would have to be implemented (see this one, for instance).

function addProperty(obj, name, initial) {
    var field = initial;
    obj["get_" + name] = function() { return field; }
    obj["set_" + name] = function(val) { field = val; }
}

This works the same as before: we create a local variable on a function, and then we create a closure.

How to use it? Simple:

var myobj = {};
addProperty(myobj, "total", 0);
window.alert(myobj.get_total() == 0);
myobj.set_total(10);
window.alert(myobj.get_total() == 10);

How to Install Sublime Text 3 using Homebrew

I originally used this page to solve the same problem in the past - however it would appear as if the sublime-text cask has been updated to now be the most recent release of Sublime Text 3. No workarounds are necessary anymore.

Installation is as simple as brew cask install sublime-text.

The changelog for Sublime Text 3 downloaded from the <code>sublime-text</code> cask.

Check file size before upload

Client side Upload Canceling

On modern browsers (FF >= 3.6, Chrome >= 19.0, Opera >= 12.0, and buggy on Safari), you can use the HTML5 File API. When the value of a file input changes, this API will allow you to check whether the file size is within your requirements. Of course, this, as well as MAX_FILE_SIZE, can be tampered with so always use server side validation.

<form method="post" enctype="multipart/form-data" action="upload.php">
    <input type="file" name="file" id="file" />
    <input type="submit" name="submit" value="Submit" />
</form>

<script>
document.forms[0].addEventListener('submit', function( evt ) {
    var file = document.getElementById('file').files[0];

    if(file && file.size < 10485760) { // 10 MB (this size is in bytes)
        //Submit form        
    } else {
        //Prevent default and display error
        evt.preventDefault();
    }
}, false);
</script>

Server Side Upload Canceling

On the server side, it is impossible to stop an upload from happening from PHP because once PHP has been invoked the upload has already completed. If you are trying to save bandwidth, you can deny uploads from the server side with the ini setting upload_max_filesize. The trouble with this is this applies to all uploads so you'll have to pick something liberal that works for all of your uploads. The use of MAX_FILE_SIZE has been discussed in other answers. I suggest reading the manual on it. Do know that it, along with anything else client side (including the javascript check), can be tampered with so you should always have server side (PHP) validation.

PHP Validation

On the server side you should validate that the file is within the size restrictions (because everything up to this point except for the INI setting could be tampered with). You can use the $_FILES array to find out the upload size. (Docs on the contents of $_FILES can be found below the MAX_FILE_SIZE docs)

upload.php

<?php
if(isset($_FILES['file'])) {
    if($_FILES['file']['size'] > 10485760) { //10 MB (size is also in bytes)
        // File too big
    } else {
        // File within size restrictions
    }
}

What is tail recursion?

Tail recursion refers to the recursive call being last in the last logic instruction in the recursive algorithm.

Typically in recursion, you have a base-case which is what stops the recursive calls and begins popping the call stack. To use a classic example, though more C-ish than Lisp, the factorial function illustrates tail recursion. The recursive call occurs after checking the base-case condition.

factorial(x, fac=1) {
  if (x == 1)
     return fac;
   else
     return factorial(x-1, x*fac);
}

The initial call to factorial would be factorial(n) where fac=1 (default value) and n is the number for which the factorial is to be calculated.

Valid values for android:fontFamily and what they map to?

Available fonts (as of Oreo)

Preview of all fonts

The Material Design Typography page has demos for some of these fonts and suggestions on choosing fonts and styles.

For code sleuths: fonts.xml is the definitive and ever-expanding list of Android fonts.


Using these fonts

Set the android:fontFamily and android:textStyle attributes, e.g.

<!-- Roboto Bold -->
<TextView
    android:fontFamily="sans-serif"
    android:textStyle="bold" />

to the desired values from this table:

Font                     | android:fontFamily          | android:textStyle
-------------------------|-----------------------------|-------------------
Roboto Thin              | sans-serif-thin             |
Roboto Light             | sans-serif-light            |
Roboto Regular           | sans-serif                  |
Roboto Bold              | sans-serif                  | bold
Roboto Medium            | sans-serif-medium           |
Roboto Black             | sans-serif-black            |
Roboto Condensed Light   | sans-serif-condensed-light  |
Roboto Condensed Regular | sans-serif-condensed        |
Roboto Condensed Medium  | sans-serif-condensed-medium |
Roboto Condensed Bold    | sans-serif-condensed        | bold
Noto Serif               | serif                       |
Noto Serif Bold          | serif                       | bold
Droid Sans Mono          | monospace                   |
Cutive Mono              | serif-monospace             |
Coming Soon              | casual                      |
Dancing Script           | cursive                     |
Dancing Script Bold      | cursive                     | bold
Carrois Gothic SC        | sans-serif-smallcaps        |

(Noto Sans is a fallback font; you can't specify it directly)

Note: this table is derived from fonts.xml. Each font's family name and style is listed in fonts.xml, e.g.

<family name="serif-monospace">
    <font weight="400" style="normal">CutiveMono.ttf</font>
</family>

serif-monospace is thus the font family, and normal is the style.


Compatibility

Based on the log of fonts.xml and the former system_fonts.xml, you can see when each font was added:

  • Ice Cream Sandwich: Roboto regular, bold, italic, and bold italic
  • Jelly Bean: Roboto light, light italic, condensed, condensed bold, condensed italic, and condensed bold italic
  • Jelly Bean MR1: Roboto thin and thin italic
  • Lollipop:
    • Roboto medium, medium italic, black, and black italic
    • Noto Serif regular, bold, italic, bold italic
    • Cutive Mono
    • Coming Soon
    • Dancing Script
    • Carrois Gothic SC
    • Noto Sans
  • Oreo MR1: Roboto condensed medium

How to do a non-greedy match in grep?

The short answer is using the next regular expression:

(?s)<car .*? model=BMW .*?>.*?</car>
  • (?s) - this makes a match across multiline
  • .*? - matches any character, a number of times in a lazy way (minimal match)

A (little) more complicated answer is:

(?s)<([a-z\-_0-9]+?) .*? model=BMW .*?>.*?</\1>

This will makes possible to match car1 and car2 in the following text

<car1 ... model=BMW ...>
...
...
...
</car1>
<car2 ... model=BMW ...>
...
...
...
</car2>
  • (..) represents a capturing group
  • \1 in this context matches the sametext as most recently matched by capturing group number 1

Why do we need middleware for async flow in Redux?

What is wrong with this approach? Why would I want to use Redux Thunk or Redux Promise, as the documentation suggests?

There is nothing wrong with this approach. It’s just inconvenient in a large application because you’ll have different components performing the same actions, you might want to debounce some actions, or keep some local state like auto-incrementing IDs close to action creators, etc. So it is just easier from the maintenance point of view to extract action creators into separate functions.

You can read my answer to “How to dispatch a Redux action with a timeout” for a more detailed walkthrough.

Middleware like Redux Thunk or Redux Promise just gives you “syntax sugar” for dispatching thunks or promises, but you don’t have to use it.

So, without any middleware, your action creator might look like

// action creator
function loadData(dispatch, userId) { // needs to dispatch, so it is first argument
  return fetch(`http://data.com/${userId}`)
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_DATA_FAILURE', err })
    );
}

// component
componentWillMount() {
  loadData(this.props.dispatch, this.props.userId); // don't forget to pass dispatch
}

But with Thunk Middleware you can write it like this:

// action creator
function loadData(userId) {
  return dispatch => fetch(`http://data.com/${userId}`) // Redux Thunk handles these
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_DATA_FAILURE', err })
    );
}

// component
componentWillMount() {
  this.props.dispatch(loadData(this.props.userId)); // dispatch like you usually do
}

So there is no huge difference. One thing I like about the latter approach is that the component doesn’t care that the action creator is async. It just calls dispatch normally, it can also use mapDispatchToProps to bind such action creator with a short syntax, etc. The components don’t know how action creators are implemented, and you can switch between different async approaches (Redux Thunk, Redux Promise, Redux Saga) without changing the components. On the other hand, with the former, explicit approach, your components know exactly that a specific call is async, and needs dispatch to be passed by some convention (for example, as a sync parameter).

Also think about how this code will change. Say we want to have a second data loading function, and to combine them in a single action creator.

With the first approach we need to be mindful of what kind of action creator we are calling:

// action creators
function loadSomeData(dispatch, userId) {
  return fetch(`http://data.com/${userId}`)
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_SOME_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_SOME_DATA_FAILURE', err })
    );
}
function loadOtherData(dispatch, userId) {
  return fetch(`http://data.com/${userId}`)
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_OTHER_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_OTHER_DATA_FAILURE', err })
    );
}
function loadAllData(dispatch, userId) {
  return Promise.all(
    loadSomeData(dispatch, userId), // pass dispatch first: it's async
    loadOtherData(dispatch, userId) // pass dispatch first: it's async
  );
}


// component
componentWillMount() {
  loadAllData(this.props.dispatch, this.props.userId); // pass dispatch first
}

With Redux Thunk action creators can dispatch the result of other action creators and not even think whether those are synchronous or asynchronous:

// action creators
function loadSomeData(userId) {
  return dispatch => fetch(`http://data.com/${userId}`)
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_SOME_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_SOME_DATA_FAILURE', err })
    );
}
function loadOtherData(userId) {
  return dispatch => fetch(`http://data.com/${userId}`)
    .then(res => res.json())
    .then(
      data => dispatch({ type: 'LOAD_OTHER_DATA_SUCCESS', data }),
      err => dispatch({ type: 'LOAD_OTHER_DATA_FAILURE', err })
    );
}
function loadAllData(userId) {
  return dispatch => Promise.all(
    dispatch(loadSomeData(userId)), // just dispatch normally!
    dispatch(loadOtherData(userId)) // just dispatch normally!
  );
}


// component
componentWillMount() {
  this.props.dispatch(loadAllData(this.props.userId)); // just dispatch normally!
}

With this approach, if you later want your action creators to look into current Redux state, you can just use the second getState argument passed to the thunks without modifying the calling code at all:

function loadSomeData(userId) {
  // Thanks to Redux Thunk I can use getState() here without changing callers
  return (dispatch, getState) => {
    if (getState().data[userId].isLoaded) {
      return Promise.resolve();
    }

    fetch(`http://data.com/${userId}`)
      .then(res => res.json())
      .then(
        data => dispatch({ type: 'LOAD_SOME_DATA_SUCCESS', data }),
        err => dispatch({ type: 'LOAD_SOME_DATA_FAILURE', err })
      );
  }
}

If you need to change it to be synchronous, you can also do this without changing any calling code:

// I can change it to be a regular action creator without touching callers
function loadSomeData(userId) {
  return {
    type: 'LOAD_SOME_DATA_SUCCESS',
    data: localStorage.getItem('my-data')
  }
}

So the benefit of using middleware like Redux Thunk or Redux Promise is that components aren’t aware of how action creators are implemented, and whether they care about Redux state, whether they are synchronous or asynchronous, and whether or not they call other action creators. The downside is a little bit of indirection, but we believe it’s worth it in real applications.

Finally, Redux Thunk and friends is just one possible approach to asynchronous requests in Redux apps. Another interesting approach is Redux Saga which lets you define long-running daemons (“sagas”) that take actions as they come, and transform or perform requests before outputting actions. This moves the logic from action creators into sagas. You might want to check it out, and later pick what suits you the most.

I searched the Redux repo for clues, and found that Action Creators were required to be pure functions in the past.

This is incorrect. The docs said this, but the docs were wrong.
Action creators were never required to be pure functions.
We fixed the docs to reflect that.

XMLHttpRequest cannot load XXX No 'Access-Control-Allow-Origin' header

As this isn't mentioned in the accepted answer.

  • This is not the case for this exact question, but might help others that search for that problem
  • This is something you can do in your client-code to prevent CORS errors in some cases.

You can make use of Simple Requests.
In order to perform a 'Simple Requests' the request needs to meet several conditions. E.g. only allowing POST, GET and HEAD method, as well as only allowing some given Headers (you can find all conditions here).

If your client code does not explicit set affected Headers (e.g. "Accept") with a fix value in the request it might occur that some clients do set these Headers automatically with some "non-standard" values causing the server to not accept it as Simple Request - which will give you a CORS error.

Deleting Objects in JavaScript

"variables declared implicitly" are properties of the global object, so delete works on them like it works on any property. Variables declared with var are indestructible.

How do I tell if a regular file does not exist in Bash?

You can also group multiple commands in the one liner

[ -f "filename" ] || ( echo test1 && echo test2 && echo test3 )

or

[ -f "filename" ] || { echo test1 && echo test2 && echo test3 ;}

If filename doesn't exit, the output will be

test1
test2
test3

Note: ( ... ) runs in a subshell, { ... ;} runs in the same shell. The curly bracket notation works in bash only.

How do I add button on each row in datatable?

take a look here... this was very helpfull to me https://datatables.net/examples/ajax/null_data_source.html

$(document).ready(function() {
    var table = $('#example').DataTable( {
        "ajax": "data/arrays.txt",
        "columnDefs": [ {
        "targets": -1,
        "data": null,
        "defaultContent": "<button>Click!</button>"
    } ]
} );

$('#example tbody').on( 'click', 'button', function () {
    var data = table.row( $(this).parents('tr') ).data();
    alert( data[0] +"'s salary is: "+ data[ 5 ] );
    } );
} );

What is the iBeacon Bluetooth Profile

If the reason you ask this question is because you want to use Core Bluetooth to advertise as an iBeacon rather than using the standard API, you can easily do so by advertising an NSDictionary such as:

{
    kCBAdvDataAppleBeaconKey = <a7c4c5fa a8dd4ba1 b9a8a240 584f02d3 00040fa0 c5>;
}

See this answer for more information.

"No Content-Security-Policy meta tag found." error in my phonegap application

After adding the cordova-plugin-whitelist, you must tell your application to allow access all the web-page links or specific links, if you want to keep it specific.

You can simply add this to your config.xml, which can be found in your application's root directory:

Recommended in the documentation:

<allow-navigation href="http://example.com/*" />

or:

<allow-navigation href="http://*/*" />

From the plugin's documentation:

Navigation Whitelist

Controls which URLs the WebView itself can be navigated to. Applies to top-level navigations only.

Quirks: on Android it also applies to iframes for non-http(s) schemes.

By default, navigations only to file:// URLs, are allowed. To allow other other URLs, you must add tags to your config.xml:

<!-- Allow links to example.com -->
<allow-navigation href="http://example.com/*" />

<!-- Wildcards are allowed for the protocol, as a prefix
     to the host, or as a suffix to the path -->
<allow-navigation href="*://*.example.com/*" />

<!-- A wildcard can be used to whitelist the entire network,
     over HTTP and HTTPS.
     *NOT RECOMMENDED* -->
<allow-navigation href="*" />

<!-- The above is equivalent to these three declarations -->
<allow-navigation href="http://*/*" />
<allow-navigation href="https://*/*" />
<allow-navigation href="data:*" />

When to use Hadoop, HBase, Hive and Pig?

Hadoop:

HDFS stands for Hadoop Distributed File System which uses Computational processing model Map-Reduce.

HBase:

HBase is Key-Value storage, good for reading and writing in near real time.

Hive:

Hive is used for data extraction from the HDFS using SQL-like syntax. Hive use HQL language.

Pig:

Pig is a data flow language for creating ETL. It's an scripting language.

What is Java Servlet?

I think servlet is basically a java class which acts as a middle way between HTTP request and HTTP response.Servlet is also used to make your web page dynamic. Suppose for example if you want to redirect to another web page on server then you have to use servlets. Another important thing is that servlet can run on localhost as well as a web browser.

how to run the command mvn eclipse:eclipse

The m2e plugin uses it's own distribution of Maven, packaged with the plugin.

In order to use Maven from command line, you need to have it installed as a standalone application. Here is an instruction explaining how to do it in Windows

Once Maven is properly installed (i.e. be sure that MAVEN_HOME, JAVA_HOME and PATH variables are set correctly): you must run mvn eclipse:eclipse from the directory containing the pom.xml.

How to access the GET parameters after "?" in Express?

Query string and parameters are different.

You need to use both in single routing url

Please check below example may be useful for you.

app.get('/sample/:id', function(req, res) {

 var id = req.params.id; //or use req.param('id')

  ................

});

Get the link to pass your second segment is your id example: http://localhost:port/sample/123

If you facing problem please use Passing variables as query string using '?' operator

  app.get('/sample', function(req, res) {

     var id = req.query.id; 

      ................

    });

Get link your like this example: http://localhost:port/sample?id=123

Both in a single example

app.get('/sample/:id', function(req, res) {

 var id = req.params.id; //or use req.param('id')
 var id2 = req.query.id; 
  ................

});

Get link example: http://localhost:port/sample/123?id=123

how to overlap two div in css?

add to second div bottomDiv

and add this to css.

 .bottomDiv{
       position:relative;
       bottom:150px;
       left:150px;
    }

http://jsfiddle.net/aw8RD/1/

Android: TextView: Remove spacing and padding on top and bottom

If you use AppCompatTextView ( or from API 28 onward ) you can use the combination of those 2 attributes to remove the spacing on the first line:

XML

android:firstBaselineToTopHeight="0dp"
android:includeFontPadding="false"

Kotlin

text.firstBaselineToTopHeight = 0
text.includeFontPadding = false